THANK YOU
The Office of Undergraduate Research would like to thank the following people
for their support of the Fall 2009 Undergraduate Research Symposium:
Nicole Bobbitt
Danny Guenther
Josh Hasam
Kelly Hill
Ed Hiss
Andrew Hoekzema
Ron Laue
Jennifer Marchal
Yifan Meng
Amy O’Brien
Tijana Orescanin
the Phage Hunters
Elizabeth Riley
Allison Schroeder
Claire Segar
Greg Sergay
Washington University Event Services
OFFICE OF UNDERGRADUATE RESEARCH
http://ur.wustl.edu
[email protected]
Henry Biggs, Director
Joy Kiefer
Kristin Sobotka
Jennifer Kohl
Tim Bono
Sandro Santoro
UNDERGRADUATE RESEARCH SYMPOSIUM
FALL 2009
Saturday, October 24, 2009
8:50 a.m. – 4:00 p.m.
Laboratory Sciences Building
We are grateful for the generous support provided by the following organizations
that have sponsored many of the projects presented today:
Air Force Research Laboratory
American Recovery and Reinvestment Act Research Grant
American Society of Hematology
Arnold and Mabel Beckman Foundation
Baseload Energy, Inc.
Burrows Wellcome Career Award
Children’s Discovery Institute (CDI)
Communities Healing Adolescent Depression and Suicide Coalition (CHADS)
The Gary Hirsch Scholarship
(The Center for the New Institutional Social Sciences)
Howard Hughes Medical Institute
Johanna D. Bemis Trust
Midstates Consortium for Math and Science
NASA Missouri Space Grant Consortium
National Cancer Institute
National Endowment of the Humanities
National Institute of Standards and Technology
National Institutes of Health
National Science Foundation
Norman Hackerman Advanced Research Program, The Welch Foundation
Sigma Aldrich
Sigma Xi Scientific Research Society, Washington University Chapter
St. Louis Children’s Hospital
Washington University in St. Louis:
Center for the Study of Ethics and
Human Values
McDonnell Center for the Space Sciences,
Robinson Award
Cognitive, Computational and Systems
Neuroscience Summer Undergraduate
Research Experience
McKelvey Scholarship
BioMedical Research Apprenticeship Program
(BioMed RAP)
Buder Center for American Indian Studies
Delos Award
Career Center
Engineering Student Council (EnCouncil)
Office of Undergraduate Research,
Catherine F. Hoopes Endowment
Consortium for Clean Coal Utilization
Environmental Studies Program
Rowe Travel Fellowship
Department of Art History and Archaeology
Fossett Fellowship for Environmental
Sustainability Research
Gephardt Civic Engagement Fund
School of Medicine
Department of Anatomy and Neurobiology
Department of Pathology and Immunology
Department of Performing Arts
I-CARES
Siteman Cancer Center
Department of Physics
Imaging Sciences Pathway
Tyson Research Center
Center for Joint Projects in the Humanities
& Social Sciences
International Activities Fund for
Undergraduates in Arts and Sciences
Undergraduate Honors Fellowship
Center for Materials Innovation
Lennette Undergraduate Research Fellowship
Undergraduate Scholars in Transition to
Advanced Research (Ustar)
Lien Undergraduate Research Award
W.H.R. Rivers Summer Research Award
Andrea Biggs Undergraduate Research Award
Bemis Scholarship, Interdisciplinary Project
in the Humanities
Department of Electrical and Systems
Engineering
Mellon Mays Undergraduate Fellowship Program
Nano Research Facility
Participants also wish to acknowledge the support of their research mentors, many of whom have
contributed funding from their grants to support undergraduate research experiences.
PRESENTERS BY SESSION/TIME
1: 10:00 a.m. - 12:00 noon ~ 1A: 10:00 - 11:00 a.m. ~ 1B: 11:00 a.m. - 12:00 noon ~ 2: 2:00 - 3:00 p.m.
Ahn, Haejun
Alexander, Ben
Andler, Caroline
Applebaum, Hallie
Ball, Cameron
Banks, Hunter
Barry, Lauren
Beasley, Brittany
Bepo, Lurit
Berns, Dominic
Bernstein, Jacob
Bethany, Chloe
Bhatia, Rani
Bhatt, Naitik
Birch, Jordan
Bolson, Philip
Borosh, Christine
Borson, Steven
Bowling, Rachel
Brewer, Stephanie
Brinkley, Kayla
Brosius, Ashley
Bruno, Frank
Burlingame, Kaitlin
Butts, Kuan
Carpenter, Shelby
Case, David
Cassady, Kalee
Caulkins, Graham
Chabra, Samir
Chang, Stephanie
Chi, Tiffany
Chiang, Joy
Choe, Eun-joo (Anna)
Chung, Yan Yi Anny
Clarke, Caitlyn
Clegg, Haley
Colletti, Peter
Craig, Michael
Cummings, Jamie
Cutz, Fernando
Czernia, Bartosz
Dang-Vu, Geoffrey
Deal, Erika
Deng, Lisa
DuGoff, Daniel
DuVall, Jarod
Ebstein, Sarah
Edinger, Chloe
Eisenberg, Michelle
Ekuta, Victor
Fahey, Paul
Fahey, Mark
Fan, Martin
Festenstein, Ross
Fine, Nathan
Finkelstein, Darren
Finkelstein, Lauren
Foley, Colin
Fox, Grace
Freedman, Kaitlin
Garcini, Alexander
Geiger, Christopher
1A
1
1
1
1
1
1B
1
1
1A
1
1
2
1
1A
1
1
2
1A
1
1
1
1
1
1
1
1
1
2
1B
1A
1A
1
1A
1B
1
1
1
1A
1
1
1A
1A
1
1A
1
2
1A
1
1
1
1A
1
1
1
1
1B
1
1
1
1
1
1
Gilchrist, Robert
Gong, Nicole
Green, Addison
Greenberg, Jacob
Greenlee, Kevin
Grossman-McKee, Morgan
Gu, Alice
Gural, Nil
Hall, Raina
Hanly, Patrick
Hanly, Elyse
Harding, Andrew
Hartstein, Kimberly
Harvey, Robert
Hasan, Saad
Hassan, Mojibade
Hawco, Nicholas
Heard, Amy
Hecht, Aaron
Held, Elizabeth
Henniger, Nicole
Hu, Jessie
Hyrc, Michal
Jacobson, Emily
Jennings, Molly
Jiang, Sirui
Jiang, Yang
Johnson, Stephen
Ju, Michelle
Kane, Erin
Kanyer, Andrew
Kelly, Laura
Kembaiyan, Preethi
Khatri, Aaditya
Knudsen, Zachary
Kollipara, Puneet
Kovalski, Joanna
Kram, Yoseph
Kress, Natalie
Krock, Rebe1a
Kumar, Anupam
Kutsenko, Alina
Ladau, Ross
LaFont, Charles
Lane-Steele, Laura
Laub, Jeremy
Laverty, Molly
Lavin, Sarah
Lebsack, Emily
Lee, Eric
Leyh, Lilly
Li, Yedda
Lieb, Sydnie
Lin, Daniel
Lin, Franck
Lindburg, Miranda
Lindsey, Stephanie
Ling III, Robert
Liu, Alan
Livingston, Jordan
Lobell, Evan
Loyet, Jessica
Mancha, Cynthia
2
2
1
1A
1
1
1
1
1
1A
1A
1A
1
1
1A
1
1B
1
2
1A
1
1
2
1
1
1A
1
1
1
1
1
1
1
1
1
1
2
1A
1
1
1
1A
1
1
1
1
1
1
1
2
1
1
1
1A
2
1
1
1
1
1
1
1
1
Markman, Nathaniel
Marshall III, Sylvester
Mart, Laura
Martinak, Bridgette
Matos, Ryan
Mau, Brian
McFadden, Kaitlin
McLaughlin, Dylan
Menard, Christopher
Meng, Alice
Merrill, Elizabeth
Messenger, David
Millis, Jonathan
Molinari, Alex
Morocco, Perry
Murphy, Benjamin
Nan, Ruth
Narla, Akhila
Narla, Akhila
Ni, Shen
Oetjen, Landon
O’Kelly, Neil
Onal, Birce
Onwuzurike, Chiamaka
Otto, Genevieve
Owens, Katharine
Palmer, Dustin
Pang, Genevieve
Pepping, Troy
Pham, Anthony
Pittman-Swint, Emily
Pitts, Jackson
Polokoff, Alexa
Pope, Marion
Post, Michael
Potter, Eric
Price, Hillary
Proctor, Travis
Quimby, Ernika
Radhakrishnan, Aditya
Rao, Chethan
Rappaport, Gilian
Rasmussen, Sara
Ravikumar, Vinod
Rayhel, Laura
Razak, Cecilia
Reynolds, Benton
Riad, Fady
Richter, John
Roberts, Jordan
Robinson, Samuel
Rockweiler, Nicole
Rooks, Alyse
Rosenfeld, Matthew
Ross, James
Rubin, Channah
Sadhu, Shubho
Salazar, Adam
Santiago, Stefan
Schaefer, Pascal
Schalker, Kamryn
Schnose, Viktoryia
Scholes, Eleanor
1B
1B
1
1
1
2
1
1B
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1B
1
1B
1
1
1
1
1B
1
1
1
1
1B
1
1
1
1B
1
1
1B
1
1
1
2
1
1
1
1
1
1
1
1
1B
1
1
1
Schroeder, Vanessa
Schwartz, Raphael
Schwartz, Ilana
Seibert, Anne
Sekendur, Cari
Shanken, Benjamin
Shen, Lucy
Shepard, Toby
Sherman, Brent
Shore, Julie
Si, Xin (Cissy)
Sidoti, Braden
Slater, Elizabeth
Slavitt, Gabriel
Small, Aeron
Sparks, Kathryn
Spence, Stephanie
Stacy, Apollo
Stein, Andrew
Stevens, Thomas
Strand, Adam
Strauss, Alex
Stromberg, Joseph
Sun, Daniel
Surick, Gabrielle
Tank, Dharmesh
Thimmesch, Erin
Thomas, Jewell
Timofte, Anca
Tombridge, Bryson
Tsai, Connie
Tsai, Michele
Undergraduate Honors
Fellows
Varriano, Jennifer
Venkataram, Sandeep
Vithayathil, Paul
Walker, Eliot
Wall, Kurt
Walton, Marcus
Wang, Charles
Wang, Kai
Wang, Michael
Wang, Yan
White, Celso
Wilbar, Nicholas
Wilkie, Lynn
Williamson, Angelique
Wilmot, Austin
Wilson, Michaela
Wolfson, Maxim
Wong, Jeannette
Woo, Dennis
Wroblewski, Hannah
Wu, Kyle
Wyler, Molly
Xu, Chen
Yalaz, Ceren
Yang, Hao
Yu, Cong (Charles)
Zhang, Bo
1B
1
1
1
1
1
1
1
1
1
2
1
1
1
1B
1
1
1B
2
1
1
2
1
1
1
1B
1
1
1
1
1B
1
1
1
2
1
1
1B
1
2
2
2
1
1
1
1
1
1
1
1
1
2
1B
1
1
1B
1
1
1B
1
FALL 2009 UNDERGRADUATE RESEARCH SYMPOSIUM
Saturday, October 24, 2009
Laboratory Sciences Building
8:50 a.m. – 4:00 p.m.
AGENDA
8:15 – 8:45 a.m.
CONTINENTAL BREAKFAST
Room 400
8:50 – 10:00 a.m.
MORNING PLATFORM SESSION
Room 250
8:50 a.m.
OPENING REMARKS – Dr. Kathy Miller
9:00 a.m.
9:15 a.m.
9:30 a.m.
9:45 a.m.
Edgar Walker
Josh Siegel
Adam Eltorai
Iboro Umana
10:00 – 11:00 a.m.
11:00 – 12:00 p.m.
POSTER SESSION 1A
POSTER SESSION 1B
12:00 - 1:00 p.m.
MID-DAY PLATFORM SESSION
12:00 – 12:15 p.m.
Undergraduate Research Mentor of the
Year Recognition – Dr. Kelly Botteron
12:15 p.m.
12:30 p.m.
12:45 p.m.
Emily Silber
Joshua Morris
Eliotte Henderson (Dance Performance)
Rettner Gallery
1:00 – 2:00 p.m.
LUNCH
Room 400
2:00 – 3:00 p.m.
POSTER SESSION 2
3:00 – 4:00 p.m.
AFTERNOON PLATFORM SESSION
3:00 p.m.
3:15 p.m.
3:30 p.m.
3:45 p.m.
Jacob Rubens
Kevin Gao
Mitch Otu
Adithya Bhat
11:00 a.m.- 3:00 p.m.
Sam Fox School of Design and Visual Arts
Student Art Fair, outside on the green.
1
Room 300
Room 250
PRESENTATIONS
Presenters are listed alphabetically by last name.
NANOSCALE CHARACTERIZATION OF BONE MINERALIZATION
Ben. E. Alexander
Mentor: Guy Genin
The nanostructure of bone determines its toughness and stiffness. Despite its importance, this nanostructure continues to be a topic of
debate. At the macroscopic level, bone’s structure is well understood: bone contains ~40% by volume type I collagen and ~50% by volume
of a stiff, carbonated apatite mineral (“apatite”), with the collagen structured in a hierarchical fashion. Views differ on the nanoscale distribution
of apatite within the hierarchical level of fibrils, which are 50-500 nm diameter aggregations of aligned and ordered triple helix collagen
molecules. Previous electron microscopy studies report that apatite exists within fibrils but not on their exterior; the view of this camp is that
mineral lies predominantly in and near the end-to-end “gaps” between neighboring collagen molecules as will be discussed in this study.
Atomic force microscopy studies, on the other hand, report extrafibrillar in addition to intrafibrillar apatite.
To clarify the nanophysiologic distribution of apatite within bone, we perform steric modeling that supports the hypothesis that apatite
exists in a banded pattern within collagen fibrils, and must also exist on the outside of fibrils. Additionally, we performed electron microscopy
analyses that further support this hypothesis.
COMPUTATIONAL MODEL OF PROTEOGLYCAN-RICH EXTRACELLULAR MATRIX
Cameron Ball
Mentor: Robert P. Mecham
Extracellular matrix (ECM) is largely composed of hyaluronic acid (HA), proteoglycan (PG), collagen fibers, and elastin globules. The ECM
has an intimate relationship with the plasma membrane (PM), and interactions between the two occur at regular intervals approximately 20
nm apart. We postulated that the mechanics of PM-ECM microdomains might assist in the assembly of elastic fibers and limitation of stress
propagation through the ECM. PGECM, short for ProteoGlycan ExtraCellular Matrix, simulates the response of the ECM to deformation
of the PM. Modeled mechanical stress and electrostatic interactions determine the behavior of the in silico matrix. While HA and collagen
give tension-resistant properties to the ECM, charged glycosaminoglycans (GAGs) on PG molecules allow the ECM to resist compression.
Simulations predict that electrostatic interactions contribute negligibly to uniaxial stress development when the matrix is in tension but resist
lateral matrix compression. The model also predicts that collagen molecules form effective barriers for stress propagation through the ECM,
and that elastin (Eln) globules approach one another following deformation of the plasma membrane. Future models of ECM microdomains
will incorporate frequency dependence and accurate geometries.
MAGNETIC ORDERING AT HIGH PRESSURE IN RARE EARTH-TRANSITION METAL-MAGNESIUM COMPOUNDS
Hunter Banks
Mentor: James Schilling
The magnetic transition temperatures for ferromagnets EuAgMg, EuAuMg and GdAgMg, as well as the antiferromagnet GdAuMg were
measured at several hydrostatic pressures using helium as the pressure medium as high as 0.7 GPa. These materials were chosen because it
has been reported that their magnetic ordering might be suppressed at only a few GPa. GdAgMg shows a strong negative pressure
dependence, while GdAuMg has almost zero pressure dependence. The Eu compounds show small, positive dependences.
DEFYING BUBBLED CIRCLE CLASSIFICATIONS:
IDENTITY IN AFRICAN IMMIGRANT POPULATIONS IN ST. LOUIS
Lurit Bepo
Mentor: Carolyn Sargent
This work studies the enculturation process of black African immigrants in St. Louis and investigates the role that this process plays in the
formation of an ethnic and social identity. In particular, I am looking at how black African immigrants define themselves in modern
American society, how they adapt to life in St. Louis, the extent to which they retain their native culture, and the historical, social, political,
and economic factors that affect each of these issues.
2
SCIENCE/POETRY, POETRY/SCIENCE
Chloe M Bethany
Mentor: Lindsey Stouffer
Perceiving a space through the sensory faculties of the human body is the most basic way that we collect information about our world, and
it is at the basis of all scholarly fields. Using as case studies a botanist and an installation artist, in this project I make an elemental study of
the way that a scientific/empirical researcher studies and represents complexities of the outside world in comparison to the methods of an
artistic/intuitive researcher. I first worked with a Ph.D. student in botany, Nicole Miller, assisting with extensive field work, and secondly
with artist Ann Hamilton, participating in a workshop which examined cultural institutions of St Louis in preparation for an installation she
will be doing at the Pulitzer Foundation for the Arts in 2010. The study manifests itself in a short scholarly essay and in an art installation
constructed in papier-mâché, wood, paint, and yarn. Through the use of symbols, diagrammatic relationships, scale, and topography I
represent a relationship between knowledge and physical perception that is intended to be both ambiguous and evocative to the viewer.
RENEWABLE ENERGY RESOURCES
Naitik Bhatt
Mentor: Arye Nehorai
Interest in energy solutions from renewable sources has grown significantly in the last decade. With the current movements in public
opinion as well as renewable mandates from the state and federal government, finding ideal sources of renewable energy has become a topic
of great importance. The utilization of technology can be very site specific, whether it be wind, solar, tidal, etc. These sites, combined with
current land use, legislation, and load demand, all factor into the efficient use of a renewable resource. This work researches the leading
technologies in renewable generation with the goal of compiling a comprehensive set of locations with the varying capacity factors available
for each technology. Attention to cost effectiveness, as well as environmental impacts, and underlying legislation will be paid to ensure the
quality and feasibility of the data. Attention to PV Solar and Wind will be emphasized.
FACTORS CONTRIBUTING TO THE FORMATION OF MARITAL ATTITUDES
Stephanie Brewer
Mentor: Michael Strube
Previous research has shown that marital attitudes and behaviors are affected by the types of areas people live in and their parents’ marital
status. The present study takes the effects of regional differences a logical step further and examines participants’ political ideologies in
relation to marital attitudes. Participants’ parents’ marital status and couple type are also examined. Participants completed a computerized
survey to determine their regional influences, their likelihood of marriage, their ideal age at marriage, the marital status of their biological
parents, and which of 4 couple types most consistently described their parent’s relationship. Participants then completed the Marital Attitude
Scale (MAS) and the Social Dominance Orientation (SDO) scale. Several significant correlations were identified between MAS scores and
other variables, and it was found that a high MAS score and a SDO independently predict a high ideal age at marriage. Further analyses of
the regional data are needed in order to determine the most critical influences on participants’ marital attitudes.
MAPPING OUT THE MESSAGE: ANALYZING GENDER IN DISNEY PIXAR’S CARS
Ashley Brosius
Mentor: Jessica Hathaway Weeks
Produced in 2006, Cars vividly depicts the story of Lightning McQueen, a hotshot rookie race car new on the circuit via detail oriented
animation, vibrant colors and a trip down the historic Route 66 to deliver a film that is captivating for children and adults of all ages. Rather
than serving as mere entertainment, this Disney favorite sends a moral message to its audience, particularly impressionable children. The
moral messages contained in this film, however, are twofold. While the film’s central premise hinges on the notion, “Life is about the journey,
not the finish line,” in actuality the movie also sends a subliminal message about gender and the journey Lightning McQueen embarks upon.
This work examines and questions masculinity in Disney Pixar’s Cars as well as the representations of gender within the film. Analysis of
whether the Disney film drives home differences in gender is followed by an application of Michael Kimmel’s “Masculinity as Homophobia”
to the main character, Lightning McQueen. While initially McQueen conforms to masculine stereotypes, it is only in taking on more
“feminine” qualities that he is able to become a more complete, developed individual.
3
AKOYA/BANDIT: PROXIMITY OPERATIONS AND REPEATABLE DOCKING WITH NANOSATELLITES
Kaitlin Burlingame
Mentor: Michael Swartwout
Akoya/Bandit is an ongoing student-built docking mission. Bandit’s mission is to flight-test proximity operations technologies, including
docking, safe navigation within 5 m of a target vehicle, on-orbit charging, and image-based navigation. The project was started in 2003 by
students and faculty at Washington University, and proto-flight hardware and documentation were presented on 20 January 2009 as part of
the Flight Competition Review of the University Nanosat-5 Program, culminating in a 2nd place finish in the national competition.
The mission elements are a 35-kg host spacecraft (Akoya) and two 3-kg proximity-operations vehicles (Bandit-1 and Bandit-2). The
minimum-success mission is to release Bandit-1 to a distance of one meter and recapture it, and can be accomplished open-loop using only
Bandit-1’s clock and cold-gas thrusters. This mission is made possible by an error-tolerant “soft dock” consisting of a hook-and-loop fastener
on an extended capture boom. Proximity operations are of significant interest in the aerospace community, and Bandit is unique in its
docking method and its small size and cost. Over the past year, proximity operations using image based navigation on a free flying vehicle
have been shown to be feasible and work on the mission is continuing to move forward.
INFLUENCE OF TEMPERATURE AND MAGNESIUM CARBONATE SATURATION ON THE
SEQUESTRATION OF CARBON DIOXIDE
David H. Case
Mentor: Daniel Giammar
Concerns about global climate change have led to research efforts aimed at sequestering anthropogenic carbon dioxide (CO2). These include
precipitation of carbonate minerals with magnesium silicates in engineered reactors or following CO2 injection into deep saline aquifers. In
this study experiments were performed to test the influence of temperature and magnesium carbonate (MgCO3) saturation on the nucleation
and precipitation of carbonate minerals. The conditions studied are relevant to full-scale sequestration systems. Aqueous phase analysis by
inductively coupled plasma mass spectroscopy (ICP-MS) quantified the rate and extent of precipitation of solid phase from solution.
Temperature significantly affected the species of solid obtained, which is supported by thermodynamic calculations. Initial MgCO3
saturation level was a strong control on the rate and extent of solid precipitation. X-Ray diffraction (XRD) analysis was conducted to identify
solids, which at 21˚C and 56˚C were magnesium carbonate minerals. At 98˚C the solid phase was identified as magnesium hydroxide,
Mg(OH)2. This suggests that at low- and mid-range temperatures carbon sequestration may be feasible, but other variables such as ionic
strength, presence of nucleation sites, and pressure remain untested.
WATER ORDERING ON ALUMINUM OXIDE SURFACES
Kalee Cassady
Mentor: Cynthia Lo
Aluminum oxide is a useful material in engineering applications such as environmental remediation for the removal of heavy metals from
water, and advanced materials such as ceramics and coatings. The structure of the clean and hydroxylated aluminum oxide (11-20) surface
has been studied using density functional theory. The lowest-energy surface structure has been found to be the stoichiometric surface, which
is in stark contrast to the results on other aluminum oxide surfaces (e.g., (0001), (1-102)). The hydroxylated surfaces have also been studied
with density functional theory, where four water molecules have been dissociated per unit cell. The results show that the stoichiometric
surface termination is favored in aqueous environments as well.
CHARACTERIZING ODORS USING ELECTRONIC NOSE SENSORS
Joy Weilin Chiang
Mentor: Arye Nehorai
Electronic sensing technology is a developing field of study that has greatly advanced over the last decade. Currently, most research focuses
on classifying odors within a limited odor set. Also of interest is detecting and distinguishing specific odors and the particular compounds
within each odor, which may be relevant for developing novel medical diagnostic tools, for example.
The goal of this project is to understand the responses of electronic nose sensors when exposed to specific food odors. In order to achieve
this, we built an experimental setup consisting of an array of three chemical sensors, their corresponding signal conditioning circuitry, and a
data acquisition device. For acquiring and processing the data measurements, a graphical user interface (GUI) was implemented in Labview.
4
A protocol was developed for calibrating the sensor responses to odorless air such that useful signals are obtained when the sensor array is
exposed to food odors. We tested the experimental setup on a small set of foods and built their characterization profiles based on the sensor
measurements.
The designed GUI and experimental setup can be used as a starting point for future research exploring chemical array signal processing
applications, such as food classification and chemical source localization.
THE THEORETICAL APPLICATION OF ASYLUM LAW WITHIN GENDER REGIMES:
A CASE STUDY OF FEMICIDE IN GUATEMALA
Caitlyn Clarke
Mentor: Gyula Csurgai, School for International Training
This study emerged from a need for the theoretical application of the current asylum law guidelines, positioned by the United Nations and
its member organizations, to the prevailing phenomena of femicide, specifically in Guatemala. Interest in the topic materialized from previous
study of the case of Fauziya Kassindja, the Togolese woman who fled to the United States to escape female circumcision. Through research
of the femicidian phenomena, it was discovered that due to the novelty of not only gender asylum law but the issue of femicide itself, including
a lack of jurisprudence on the subject, the connection between the two had never been made. In this situation, what legal precedent would
apply to a Guatemalan woman seeking asylum in another country through the claim of the threat of femicide?
To research the topic, several UN experts including those from the Office of the High Commissioner for Human Rights and the High
Commission for Refugees, the Geneva Democratic Center for Armed Forces, and the International Organization for Migration were
interviewed. I also read many documents including the Guatemalan Femicide Law, the work of anthropologist Victoria Sanford, and documents
from the Guatemalan Human Rights Commission and the Center for Gender and Refugee Studies in California. To resolve the issue of
femicide and gender asylum law, several recommendations were made in order to ease the asylum application process for women applying
under the threat of femicide. It was also discovered that in order to bridge the gap between gender asylum law and femicide, further study
into femicide, specifically its causes, consequences, and context would have to be procured. Through research, I concluded that as femicide
becomes a growing issue of international concern, it should be integrated into the gender asylum legal framework. In the future, I plan to
find specific cases, classifiable as pursing asylum under the threat of femicide, and demonstrate how the gender asylum legal framework,
including UN guidelines can be applied.
DETERMINATION OF THE THERMODYNAMICS AND KINETICS OF IRON NANOPARTICLE
SELF-ASSEMBLY ON AN ALGINATE SUBSTRATE
Peter Colletti
Mentor: Young-Shin Jun
The early stage aggregation kinetics and thermodynamics of the self-assembly process undertaken by iron nanoparticles in the presence of an
alginate substrate are measured with atomic force microscopy (AFM). Samples of clean quartz substrate are exposed to solutions of iron
nanoparticles and alginate in order to characterize the aggregation of iron nanoparticles on the surface, the coating of the surface with
alginate, and the self-assembly process itself. This is determined by observing changes in the surface morphologies of the quartz substrate.
No definitive information concerning the kinetics could be obtained, but aggregation and assembly patterns similar to those previously found
by other researchers were observed.
THE HAITI PROJECT
Jamie Cummings
Mentor: Robin Shepard
Haiti, the western hemisphere’s poorest country, is finding relief from its malnutrition woes through an innovative peanut butter. Meds and
Food for Kids, an organization based out of St. Louis, runs a factory in Haiti that produces enough peanut butter to cure 3,000
malnourished children every year. The factory buys its peanuts from Haitian farmers, but due to mold growth caused by inadequate drying,
approximately 40% of those peanuts are thrown out. Washington University’s Engineers Without Borders is working to solve this mold problem
by developing a simple, affordable peanut dryer that can be built by farmers in Haiti. This summer, students built and tested a passive solar
peanut dryer in St. Louis, which will ultimately help farmers reduce peanut mold and allow Meds and Food for Kids to produce more of
their life-saving peanut butter.
5
CONSTRUCTIONS OF NATIONALISM IN THE GERMAN PERIODICAL PRESS:
THE WORK OF GUSTAV FREYTAG AND BERTHOLD AUERBACH, 1848-1871
Erika Deal
Mentor: Lynne Tatlock
This research represents an integral part of a larger project which attempts to explore the significance of communication between literary
media through the work of authors Gustav Freytag and Berthold Auerbach in the years between 1848 and 1871. This period is often judged
as one in which political and literary activity was at a low point, and especially in which nationalism was relatively unpopular among the
middle class. Furthermore, the reading public at this time began to prefer journals and newspapers to books, which threatened the “national”
significance of literature. However, I attempt to demonstrate that the work of these authors poses a challenge to these generalizations. Both
wrote popular novels during the period that maintained a nationalist agenda, and both recognized the usefulness of periodical publications
to supporting their goals. Furthermore, their work in journalism and literature, taken together, can show how the “unpopular” ideas of
nationalists could be further developed and popularized through the integrated workings of literary production and the periodical press. The
research presented here focuses specifically on the authors’ engagement with the periodical press and examines how they used journalism to
advance a political and literary agenda.
CHAT ROOM MEETS WAITING ROOM:
WEBMD AND THE TRANSFORMATION OF THE DOCTOR-PATIENT RELATIONSHIP
Chloe Edinger
Mentor: Kate Bloomquist
More than just a purveyor of reliable medical information, amongst the pages of WebMD users can experience a cyber-catharsis and feel a
virtual sense of connection to nameless strangers. However, the same hyperlinks building communities have foundations in fear. The message
boards give license to complete strangers to advise and sympathize with no MCATS or accountability necessary. On the WebMD message
boards the members of the community are the authors, editors, and critics, sustaining the pages of paranoia and therapy with each keystroke.
As the availability of once limited medical knowledge changes the dynamics of power in the doctor-patient relationship, there is a need for
doctors to address Internet informed patients and define new norms for behavior in the clinical setting. Many doctors take the advent of the
proactive nature of the health consumer as a threat to their authority and paternalistic role. It is the responsibility of the physician to inform
patients about the credibility of information online and to respect the patients’ desire for autonomous decision-making. The purpose of this
research is to determine methods in which people are consuming and using information obtained from WebMD, how this information
translates into the clinical setting, and consider the implications this knowledge has on health outcomes. The key to avoiding resentment
and self-diagnosis that eventually lead to negative health outcomes, is proper education of medical professionals, bridging the gap between
consumer knowledge and clinical relationships through positive communication. This research can further be applied to developing new
research into the reactions of physicians presented with Internet informed patients, and to teaching standardized dialogue and clinical
behaviors to doctors in the age of the health consumer.
NEURAL CORRELATES OF PREDICTION UNCERTAINTY
Michelle Eisenberg
Mentor: Jeffery Zacks
As people participate in and observe the continuous flow of actions and events that compose their everyday lives, they segment the stream
of action into discrete events. The brain constantly makes perceptual predictions about what will occur next and perceives event boundaries
when transient prediction errors peak. Prediction of rewarding stimuli is correlation with activation of dopaminergic nuclei and the striatum.
Although making predictions during event segmentation does not result in a tangible reward, we hypothesized that the substantia nigra (SN),
ventral tegmental area (VTA), and the striatum would be activated when prediction errors are made during event segmentation, i.e., at event
boundaries. In this study, subjects underwent fRMI scanning while watching movies of everyday activities. During pauses located either within
events or at event boundaries, subjects completed a forced-choice task in which they predicted what would occur next in the movie. We traced
the right and left SN, VTA, caudate, and putamen and performed region of interest analyses. Activity in the right SN was significantly higher
during prediction across event boundaries than within events, meaning that this area is likely involved in prediction.
6
IDENTIFYING REGULATORY ELEMENTS OF THE ZEBRAFISH HYPOCRETIN RECEPTOR
Victor Ekuta
Mentor: David Schoppik, Harvard University
Sleep consumes nearly a third of our lives. Nevertheless, the mechanisms governing sleep regulation are poorly understood. In recent years,
approaches to sleep research have focused on the hypocretin/orexin system, which is a sleep/wake regulator that has been implicated in the
sleep disorder narcolepsy. Previous research has characterized a sleep-like state in zebrafish that is regulated by hypocretin/orexin. In zebrafish,
the hypocretin receptor is expressed in many different neural tissue clusters, positing a distributed role for the hypocretin peptide. We are
primarily interested in the role of hypocretin in modulating locomotor aspects of the sleep wake cycle. By understanding the regulatory factors
controlling the expression of the hypocretin receptor, it may be possible to target neurons involved in the modulation of locomotion. Here,
we attempt to identify putative regulatory noncoding sequences that drive fluorescent protein expression in neurons containing the hypocretin
receptor. To test for potential enhancer activity of candidate sequences, we injected 21 DNA constructs into wild-type, 1-2 cell zebrafish
embryos. Injected embryos were analyzed for putative enhancer activity by visualization of expression patterns, via fluorescence microscopy,
at 96 hours post fertilization. We hope an understanding of hypocretin expression regulation may yield insights into the genetic regulation
of sleep.
SEQUENCES LOCATED WITHIN THE N-TERMINUS OF THE PARKINSON’S DISEASE-ASSOCIATED
GENE, LRRK2 LEAD TO INCREASED AGGREGATION
Mark Fahey
Mentor: Karen O’Malley
Mutations in the large, multi-functional protein, LRRK2, are associated with both familial and idiopathic Parkinson’s disease hence
understanding its biological and pathological functions may lead to novel therapies. Because LRRK2 forms aggregates in vitro and in vivo,
we used bioinformatics approaches to identify regions of LRRK2 likely to induce cross-linked β-sheet formation. Using two different algorithms
the same unique region in the N-terminus of LRRK2 was identified as being aggregation prone. To test this region, GFP fusion constructs
targeting the first 938 amino acids of LRRK2 as well as the C-terminus (967-2527) were generated. The LRRK2 fragments as well as wildtype clones were analyzed for aggregation propensity following transfection and expression in SH-SY5Y cells using an unbiased, automated
high-content imaging paradigm. Results verified that the region predicted did indeed lead to increased aggregation of N-terminal LRRK2
compared to other regions. Moreover, deletion of amino acids within this region dramatically decreased aggregation suggesting that this
region may be an important determinant in the propensity of LRRK2 to form higher order structures. Similar results were observed after
transfection in dissociated cultures of dopamine neurons. Because wild type LRRK2 also forms aggregates albeit much smaller ones in
heterologous cell types, we tested whether the full length protein was cleaved when over-expressed in SH-SY5Y cells. Cells were transiently
transfected with WT LRRK2 plasmid containing an N-terminal GFP tag and then allowed to develop aggregates for 24 hrs. Following fixation
cells were scored for co-localization of GFP and cy3-labeled anti-C-terminal LRRK2 antibody. Only 4% of aggregates defined as ≤ 5 micrometers
exhibited co-localization suggesting that cleavage was occurring. Western blots of cell lysates were consistent with LRRK2 cleavage in a timedependent manner. Thus, WT LRRK2 can undergo cleavage such that a truncated form of the protein is produced which has a high propensity
to aggregate. It is not yet clear whether increased aggregation accelerates or retards cell death due to LRRK2 over-expression.
CONFORMATIONAL CHANGES OF HIV-1 TAR RNA UPON BINDING OF NEOMYCIN-B
Martin Fan
Mentor: Tianbing Xia, University of Texas at Dallas
The Trans-Activation Region (TAR) of HIV-1 is a short RNA transcript that the virus requires to up-regulate transcription of its genome.
Its function is based largely on its three-nucleotide bulge region, which recruits an essential transcription factor known as Tat protein. It has
previously been demonstrated that Neomycin-B acts as a ligand to TAR RNA, causing the bulge region to assume a conformation that is not
recognized by Tat protein. To determine additional structural details of this particular conformation, we have obtained two synthetic
oligonucleotides in which base C24 or base U25 of the bulge has been replaced by a fluorescent analog, 2-aminopurine. Since this analog
will undergo fluorescent quenching if it is in a stacked conformation with any RNA nitrogenous base, we have been able to infer details about
how the stacking interactions of bases 24 and 25 are affected by Neomycin-B. Steady-state fluorescent titrations performed with Neomycin-B
as the ligand reveal that increasing the Neomycin-B concentration initially causes base 24 to flip out of a stacked conformation, and then
causes it to go into an undetermined stacked conformation. In addition, increasing Neomycin-B concentration causes base 25 to assume an
undetermined stacked conformation. We have further verified these observations by performing femtosecond time-resolved spectroscopy,
which has the additional ability to reveal details on what particular bases the fluorescent analog might stack with, on complexes of TAR RNA
with Neomycin-B.
7
DENSITY FUNCTIONAL THEORY ANALYSIS OF METHANE DEHYDROGENATION ON PLATINUM
NANOCLUSTERS FOR LIQUID FUEL PRODUCTION
Nathan Fine
Mentor: Cynthia Lo
Methane has proven itself to be a useful precursor for the production of liquid fuels and other value-added chemicals through the FischerTropsch process, but currently its potential is limited since it appears to be too energetically stable to undergo direct conversion to higher
hydrocarbons and other liquid fuels. It is believed that more technologically advanced nanoscale catalysts may facilitate more economical and
direct methods of production. In this study, the physisorption of methane on a 20-atom tetrahedral platinum nanocluster, and the
chemisorption of dehydrogenated methane derivatives have been modeled using density functional theory. These calculations provide a
strong base for computing the reaction pathway, using the nudged elastic band and related methods, for catalytic methane dehydrogenation
on Pt nanoclusters. Furthermore, the nanoparticle structure, composition and placement on a metal oxide support may be varied to design
catalysts with improved yield, selectivity, and stability for the direct synthesis of liquid fuels from methane.
THE RIGHT NOT TO BE PUNISHED
Grace Fox
Mentor: Kit Wellman
This thesis investigates punishment and overcriminalization in the United States. Specifically, I am interested in the right not to be punished
and how that right should translate into our criminal system. Unlike Douglas Husak in his book Overcriminalization, I argue that the right
not to be punished is a fundamental right and should be treated as such. Also, I explore the possibility that this will lead to a more just
criminal justice system. I do not want to argue that treating the right not to be punished as a fundamental right will annihilate our criminal
justice system as we know it; rather, I argue that it places the onus on the state to uphold the justice of the system. I also use the proliferation
of inefficient and overreaching sexual conduct laws as an example of our bloated criminal justice system.
UNDERSTANDING BIKE CULTURE:
A COMPARATIVE STUDY OF BICYCLE USE IN EUROPE AND THE UNITED STATES
Addison Green
Mentor: Margaret Garb
The term ‘bike culture’ has two related but different meanings. In countries that support, encourage, and have high bicycle usage, it refers
to cooperation between government and private organizations to achieve these goals. In countries with relatively low bicycle usage, like the
U.S., bike culture refers to a cycling subculture. As the United States searches for low carbon solutions to transportation problems, it must
pursue the former definition as it attempts to bring cycling from a subculture into the mainstream. To compare these two definitions, I
conducted a study which draws on theoretical material from economics, environmental policy, and urban development as it relates to the
cities of Amsterdam and Copenhagen. This project evaluates the steps these cities have taken to promote bike use through infrastructural,
social, governmental, and market incentives. American bike commuters face several challenges, including strong opposition from small
business and car owners. By better understanding the attributes that Amsterdam and Copenhagen have which resulted in a perfect habitat
for cyclists and a thriving urban bike culture, I assess which changes can be made to our own active and public transportation networks. In
doing so, reasonable solutions to the problems American cyclists face through new technologies and old mechanisms are identified.
THOUGHTS ON THE EFFECTIVENESS OF FOREIGN AID
Morgan Grossman-McKee
Mentor: Sebastian Galiani
Since the 1960s, the literature on the effectiveness of foreign aid has struggled to reach robust conclusions. In 2004, Michael Clemens and
two coauthors pioneered a new approach to studying foreign aid. Clemens et al isolated components of aid that they believed could
realistically promote short-run growth, and found that indeed such aid flows were robustly correlated with GDP growth.
While this new strategy appears promising, it needs to be replicated by outside researchers. The present study attempts to reproduce the
results from Clemens et al, using a similar but slightly-updated data set. Unfortunately, the seemingly-stable results from Clemens et al do
not appear to survive this attempted replication. Although several factors that could influence the results still need to be investigated, it
appears that a robust link between foreign aid and growth remains elusive.
8
MONITORING TOPOCHEMICAL PHOTOCHEMISTRY IN THE SOLID STATE IN MOLECULAR
CRYSTALS AND SUPRAMOLECULAR COMPLEXES
Kimberly Hartstein
Mentor: Sophia E. Hayes
We have monitored [2+2] photocycloadditions in the solid state of both molecular crystals, including cinnamic acid (and its derivatives) and
cinnamoyl-substituted polymers. The reaction kinetics can be followed using 13C NMR due to chemical shift resolution between reactants
and products. We have detected a polymorphic phase change in molecular crystals, and single crystal NMR has revealed an unexpected
splitting of product resonances, attributable to two magnetically inequivalent sites, while x-ray diffraction suggests a single crystal site. These
apparent anomalies will be discussed. This photoreaction is also being studied in other species that will be discussed.
WOMEN ONLY?: FINDING A PLACE FOR MEN IN DIRECT SERVICE PROVISION FOR
SURVIVORS OF SEXUAL ASSAULT AND DOMESTIC VIOLENCE
Bobby Harvey
Mentor: Jami Ake
This project investigates the gender segregation of the feminist movement in general and the movement to end domestic violence and sexual
assault in particular. Men have been relegated to certain tasks within these movements, often unable to break out of the roles allocated to
them by the organizations for which they work. Men in this field usually counsel abusers and batterers instead of working directly with the
victims and survivors of the violence while women usually take on the role of helping survivors directly. The aim of my research is to investigate
this gender segregation by talking to men and women in the field about their experiences and opinions on male involvement in direct
service provision. Interviews are ongoing, but they have shown a wide variety of opinions on male involvement in this field, demonstrating
the need for a larger conversation on the topic.
TRANSCRIPTIONAL REGULATION OF FGF1 BY PPARγ: EFFECTS ON ADIPOGENESIS
Mojibade N. Hassan
Mentor: Ronald M. Evans, Salk Institute
Nuclear receptors (NRs) are a superfamily of ligand activated transcription factors. The Evans laboratory developed a high-throughput screen
to determine the regulation of genes by NRs. Recently regulation of Fibroblast Growth Factors (FGFs) by NRs was discovered, so one of
these screens done in the lab included testing the entire family of FGFs for regulation by NRs. Of particular interest was the strong and
specific transcriptional regulation of FGF1A, one of the alternative splice variants of FGF1, by peroxisome proliferator-activated receptor
(PPAR)γ . PPARs are a subgroup of NRs that are involved in lipid metabolism and regulate genes by binding to the PPAR response element
(PPRE). In particular, PPARγ is involved in adipogenesis and fat storage.
In this project we characterized the FGF1A promoter. First, we identified a putative PPRE and determined its functional activity by
mutational analysis. Second, we investigated the evolutionary conservation of the FGF1A promoter, and its regulation by PPARγ. We show
that the FGF1A promoter and its regulation by PPARγ is highly conserved in a wide range of mammals suggesting that this regulation is
functionally important.
STUCK IN THE WAITING, A DANCE PERFORMANCE
Eliotte Henderson
Mentor: David Marchant
QUANTIFICATION OF THE TEMPORAL STABILITY OF ARTERIAL SPIN LABELING
FUNCTIONAL MAGNETIC RESONANCE IMAGING
Nicole Henniger (Knox College)
Mentor: Kevin Black
ASL fMRI techniques use magnetically labeled blood water as a tracer to directly measure cerebral blood flow (CBF), a correlate of neural
activity. Labeled images and unlabeled control images are alternately captured, and the creation of a data series through pairwise subtraction
of proximate labeled and control images effectively avoids the error introduced by slow drifts in low frequency scans. Previous research has
established the stability and reproducibility of ASL MRI imaging over time during resting states. Other studies have begun to investigate the
9
use of ASL to measure functional and pharmacological alteration of global and regional CBF. Because many medical applications of MRI
require low frequency scans, a better understanding of the temporal stability of ASL measurements during realistic experimental manipulations
is necessary. Additionally, current methods of ASL MRI suffer from lower signal to noise ratio than other imaging methods. This ratio may
be improved with the use of more powerful scanning equipment, but few studies examining low frequency ASL MRI have used 3.0T scanners.
The present study investigates the temporal stability of ASL images of regional activation during visual stimulation using a 3.0T MRI scanner.
MODELING OF INP OPNMR SIGNALS
Michal Hyrc
Mentor: Sophia Hayes
Over the last several decades, nuclear magnetic resonance (NMR) has emerged as a powerful spectroscopy technique for accurate, precise and
non-destructive characterization of both liquid and solid chemicals. In 1968, Lampel showed that the NMR signal in silicon could be greatly
amplified by irradiating the sample with light, giving birth to optically pumped nuclear magnetic resonance (OPNMR). His discovery
allowed NMR to overcome its principle inhibition, low sensitivity. Used extensively in the scientific community, OPNMR is poised to
become an even more popular technique as its applications broaden in scope. Hayes, Michal and Goto have all used OPNMR to characterize
semiconductors, in particular GaAs and InP. Unfortunately, the potential of OPNMR is hampered by poor understanding of the physical
phenomena that make it possible. One area of intensive research is the modeling of OPNMR signals as a function of photon energy. Mui et
al. have done this for gallium arsenide (GaAs), but no such model exists as of now for indium phosphide (InP). This project adapted the
existing GaAs model for InP.
LIFTING AWAY OF MORALS AND IDENTITY IN THE LORAX
Yang Jiang
Mentor: Nick Miller
Dr. Seuss’s 1971 children’s story, The Lorax, tells the tale of the demise of a Truffula forest because of the greed of a green creature known as
the Onceler. Although clearly advocating protection of the environment, this picture book fosters implications targeting a more mature audience.
Through the juxtaposition of the Truffula habitat, where creatures live harmoniously and have abundant resources, with the Onceler’s selfadvancing world, where natives experience homelessness and starvation for the first time, the text seems to advocate a return to a preindustrialized past. Dr. Seuss’s drawings (where a funnel shape repeats in the Onceler’s body, his factories, and the Truffula trees) suggest a
second interpretation that the Truffula environment symbolizes and warns against an individual’s moral decay. Connecting and clarifying
these claims, Amitai Etzioni, John Kavanaugh, and Heinz Hengst offer definitions of morality and explore possible psychological and
sociological factors influencing the Onceler’s actions. Research on these articles complicated and led to my final claim that the text calls for
the return to a preindustrial community where people are not pressured to impose their wills on others and sink into amorality as a means
of achieving individuality in an increasingly mechanized world.
SPATIAL NICHES IN MIXED-SPECIES EXHIBITS
Erin Kane
Mentor: Robert Sussman
Looking at two different mixed-species exhibits of primates at the St. Louis Zoo, I evaluated whether or not captive primates use spatial
arrangement to maintain their distinct niches, and whether the distinctiveness of the niche determines the success of the exhibit. Based
particularly on the frequency with which each species used different parts of their exhibit, it was determined that spatial arrangement is
distinct between species, and that monkeys arrange themselves non-randomly within their enclosures. I did not find that the more distinct
the niches, the lower the rates of agonism (and therefore the more successful). To the contrary, the exhibit with more distinct spatial niches
had higher inter-species agonism.
OPTIMIZATION OF DETECTOR GEOMETRY FOR BALLOON-BORN GCR COLLECTION
Andrew Kanyer, Jr.
Mentor: Robert Binns
In any satellite or balloon-based experiment, balancing payload size, weight, and cost is a primary concern. Designers strive to produce the
most effective detector possible while respecting the various cost, weight, and size restrictions dictated by the balloon in use. While this balance
10
is tedious and difficult to achieve using analytical methods, computer simulation can simplify the process. This work explores the challenges
and benefits that developing such a simulation introduces into the design process for a balloon-born galactic cosmic ray detector.
THE WORD “RECESSION” AND CONFIDENCE IN THE ECONOMY
Laura Kelly
Mentor: Brett Kessler
During the past year, whether or not the United States economy is in a recession has been subject to debate. Many economists have questioned
whether this debate in itself has contributed to the decline in consumer confidence. This experiment tested whether the media’s framing of an
economics article can change a consumer’s decisions, and whether economic literacy can lessen this effect. It examined whether participants
who read a fictitious news article with the word recession in it made different economic decisions than a group of participants who read an
article that was identical in content, but substituted recession for the formal economics definition, negative real gross domestic product growth
for two or more consecutive quarters.
FGFR2 POLYMORPHISMS AND ENDOMETRIAL CANCER RISK
Aaditya Khatri
Mentor: Paul J. Goodfellow
Fibroblast growth factor receptor 2 (FGFR2) plays a critical role in cell growth and signaling. It is abundantly expressed in the adult
endometrium and somatic activating mutations in FGFR2 are seen in ~16% of endometrioid endometrial cancers. Two recent genome-wide
association studies identified alleles in FGFR2 associated with breast cancer risk. Given the similar role estrogen plays as a risk factor in both
breast and endometrial cancers and the involvement of FGFR2 activating mutations in endometrial cancer, we sought to determine whether
variation in FGFR2 contributes to endometrial cancer risk.
Phase 1: We examined 14 haplotype tagging SNPs in FGFR2 that capture most of the variation in the gene in 363 well-characterized
Caucasian endometrial cancer patients (ages 26 - 92 years at diagnosis) and 336 Caucasian cancer-free controls. SNPs were genotyped using
PyrosequencingTM. The rs1219648 allele tagging the LD block previously associated with breast cancer risk showed no evidence for
association with endometrial cancer. rs2912760, rs1863741, and rs2981428, however, showed a difference in allele frequency in cases and
controls that approached statistical significance. In particular, the rs1863741 minor allele (G) was more common in cases (46%) than
controls (37%) (Odds ratio 1.39, 95% CI 1.11-1.73, p=0.004).
Phase 2: The three SNPs that showed a significant difference in allele frequency in cases and controls in Phase 1 were genotyped in an
additional 376 Caucasian endometrial cancer patients and 188 cancer-free controls in Phase 2 of the study. Data analysis of the combined
cases and controls in Phase 1 and Phase 2 showed that there was no longer a significant difference in allele frequency between the cases and
controls. We are currently analyzing data to determine if any of the SNPs are associated with clinicopathologic and molecular variables
(patient body mass index, tumor grade, age-at-diagnosis, and DNA mismatch repair status) that have been associated with estrogen levels in
endometrial cancer patients. Our data indicate the FGFR2 susceptibility allele(s) associated with breast cancer is unlikely to play a role in
endometrial cancer. None of the SNPs from the 14 LD blocks of FGFR2 seems to contribute to risk for endometrioid endometrial cancer.
ROBOTIC MICROPHONE SENSING: DATA PROCESSING ARCHITECTURES FOR
REAL-TIME ACOUSTIC SOURCE POSITION ESTIMATION
Zachary Knudsen and Raphael Schwartz
Mentor: Arye Nehorai
In the previous work “Acoustic source location using cross-correlation algorithms,” we found that the performance of the 2D position
estimation algorithms using two pairs of microphones depends on array variables such as the distances between the individual and pairs of
microphones, and also the sampling frequency. Therefore, we propose to build a robotic microphone array with autonomous control of the
array geometry and sampling rate for improving the localization performance of an acoustic source in 2D space. In particular, in this project
we focus on developing data processing architectures for estimating in real-time the 2D locations of an acoustic source. We implemented our
algorithms in Labview combined with Matlab and developed a graphical user interface that allows for easy interaction with the experimental
setup. The system allows for tracking a fixed and moving wideband acoustic source.
11
SLEEP HOMEOSTASIS IN DROSOPHILA MELANOGASTER:
THE INVOLVEMENT OF PUTATIVE METABOLIC GENES IN SLEEP REGULATION
Natalie Kress and Adam Strand (Gustavus College)
Mentor: Paul Shaw
There is a clear interaction between sleep and metabolism, where insufficient sleep results in metabolic defects such as obesity and endocrine
dysfunction. Conversely, recent data from Paul Shaw has shown that mutations in enzymes involved in lipid metabolism change sleep behavior.
Unfortunately, the mechanism of how lipids control the regulation of sleep is unknown. In the Shaw lab, we use the model organism
Drosophila melanogaster to understand mechanisms underlying sleep. Previous microarray experiments in the lab have identified multiple lipid
metabolism genes involved in sleep regulation. One such gene with unknown function but homology to Acyl-CoA synthetases (ACS) is
CG9009. Using techniques such as P-element mutagenesis, RNA interference (RNAi), qPCR, and various sleep behavior parameters we hope
to elucidate the molecular interaction between sleep and metabolism through understanding the role of this putative metabolic gene, CG9009.
PROBING NEURONAL CONNECTIVITY IN THE MAMMALIAN CIRCADIAN PACEMAKER
Rebecca Krock
Mentor: Erik Herzog
The suprachiasmatic nucleus (SCN) of the mammalian hypothalamus is required for near-24 hour behavioral and physiological rhythms.
Individual neurons in the SCN have circadian rhythms in firing rate and clock gene expression. Circadian synchrony between oscillators is
critical for coherent output from the SCN, and thus for behavioral rhythmicity. How these neurons remain synchronous is unclear. Here we
study the underlying functional connectivity of neurons within synchronized SCN networks to determine which types of communication
may be important for synchrony. By cross-correlating neuronal spike trains recorded on multielectrode arrays, we found evidence for
significant connectivity between individual neurons. These correlations peaked within 10 ms of firing by a reference neuron, and were classified
as excitatory or inhibitory. We found that communication between neuron pairs oscillated over the day, much like their electrical activity.
Application of specific receptor antagonists allows us to determine which neurotransmitters mediate these correlations. Furthermore, we can
determine whether this millisecond-resolution communication is necessary for circadian synchrony by applying specific receptor antagonists
to SCN slices and imaging the expression of a bioluminescent reporter driven by the clock gene Period2 (Per2::Luc). Preliminary results
indicated that blockade of GABA signaling by application of 200 µM bicuculline decreased the number of inhibitory correlations by ~90 %
and decreased the number of excitatory correlations by ~ 0 - 50% (n=3 cultures). Bicuculline did not, however, affect circadian synchrony in
SCN slices. Blockade of ionotropic glutamate receptors with APV and CNQX also did not affect the Per2::Luc rhythm in SCN slices. These
results indicate that we can effectively probe the connectivity between individual SCN neurons using spike train analysis and determine how
oscillators couple to maintain circadian synchrony.
MALE CIRCUMCISION AS HIV PREVENTION:
THE POLITICS OF LOCAL PERCEPTIONS AND GLOBAL PUBLIC HEALTH POLICY IN UGANDA
Anupam Kumar
Mentor: Shanti Parikh
Recent studies have shown that medical male circumcision (MMC) reduces HIV transmission by over 50%. However, broad institutionalization
of MMC carries profound societal implications. Circumcision has long been practiced as a rite of passage in many communities in Uganda
and throughout sub-Saharan Africa. As the government of Uganda seeks to create a nationwide network of MMC sites as part of an effort
to combat the spread of HIV, its policies may encounter diverse local responses. Thus, cultural understandings of male circumcision and of
non-circumcised men should be illuminated prior to implementation of the MMC policy. I conducted ethnographic research and interviews in
Eastern Uganda to examine how men currently understand the procedure of MC, as it relates to masculinity and adulthood, and how governmentsponsored MMC may be received in these communities. The conclusions of this work regard the incorporation of ethnographic data by the
Ugandan government to generate culturally appropriate public health messaging about MMC as a means for HIV prevention. This study
is additionally a preliminary analysis of the important transition of male circumcision from a cultural practice embedded within a larger
coming of age process into state-sponsored public health and medical procedure.
12
X-RAY SCATTERING ANALYSIS OF LIQUID METALS AND ALLOYS BY WAY OF ELECTROSTATIC LEVITATION
Ross Ladau
Mentor: Ken Kelton
This work is an analysis of data that was obtained through X-Ray scattering of metals by means of Beamline Electrostatic Levitation. The
purpose was to glean the structural properties of the metallic liquids. Metallic samples are levitated in electric fields then melted and X-rays
scattered through them. Computer programs are used to organize this data into ways that reveal the atomic structure of the metallic liquids.
The analysis is intended to fill holes in our knowledge of how the atoms of pure metals and alloys arrange themselves in the liquid. No
significant results have been obtained thus far, but further analysis of the data may be done.
ROBOTIC MICROPHONE SENSING: DESIGN OF A ROBOTIC PLATFORM AND ALGORITHMS FOR
ADAPTIVE CONTROL OF SENSING PARAMETERS
Charles LaFont
Mentor: Ayre Nehorai
In our previous undergraduate research project on “Acoustic source location using cross-correlation algorithms: we found that the performance
of the 2D position estimation algorithms using two pairs of microphones depends on array variables such as the distances between the
individual and pairs of microphones, and also the sampling frequency. Therefore, we propose to build a robotic microphone array with
autonomous control of the array geometry and sampling rate for improving the localization performance of a wideband acoustic source in
2D space. In particular, in this project we designed two mobile robotic-platforms carrying a pair of microphones each. Each platform is capable
of real-time communication between the PC and the robot microcontroller independently. We designed a control algorithm for modifying
adaptively each robot position along a single axis such that the resolution for estimating the source position is improved. We tested the
performance of our system using numerical examples and real experiments.
COMMUNITY SOLIDARITY AND NEGOTIATION FOR SERVICES IN THE PERIPHERAL SQUATTER
SETTLEMENTS OF LIMA, PERU
Molly Laverty
Mentor: Bret Gustafson
The shantytowns of Lima, Peru present a unique topic of study of the role of community identity and its constructive function in marginal
settlements. Community action and solidarity are at the core of the reason why the shantytowns have experienced such success and
permanency since the initial land invasions of the twentieth century. The residents have discovered and proven that their voice, and not their
exit, is what will bring improvement to their settlements. In determining the most effective means of interacting with the government, I have
explored how these diverse community groups are organized, who organizes them, where the community resources come from, and how
resources are distributed within the community. Through a cohesive community and strong willed actors, the residents of these towns have
created a shining example of negotiation for services and amenities from the government, while at the same time created thriving urban
centers where once there was only desert sand.
LABORATORY STUDY OF PRESOLAR CARBONACEOUS STARDUST
Emily Lebsack
Mentor: Tom Bernatowicz
Presolar grain research is an exciting new field in which stardust, formed in the stellar outflows of red giants and supernova ejecta, is studied
in the laboratory. These precious grains give us unprecedented information regarding the evolution and age of our galaxy, nucleosynthesis,
supernova mixing processes, the composition of the stellar atmospheres in which the grains were formed, and the processes undergone by the
meteoritic parent bodies of the grains in the interstellar medium. In this study we discuss the methods of finding and preparing these rare
dust particles for study. In particular we draw attention to the preparation of supernova graphites from the meteorite Orgueil and rare AB
type silicon-carbide (SiC) grains for TEM study by ultramicrotome sectioning. We also focus on the importance and methods of finding
“pristine” presolar SiC grains—those that have not been exposed to corrosive chemicals commonly used to isolate the grains.
13
LOOKING THROUGH A LENS: THE EFFECTS OF MACHISMO ON WOMEN IN LA PAZ, BOLIVIA
Lilly Leyh
Mentor: Bret Gustafson
This research was conducted in La Paz, Bolivia where I interviewed women on their experiences and opinions on machismo, male chauvinism,
while living in the offices of the anarchist-feminist group, Mujeres Creando. The goal was to conduct enough interviews, and take enough
video footage and photographs to create a photo documentary. By living with Mujeres Creando I gained an insiders perspective on what would
be considered one of the more radical opinions of Bolivian women, as well as connections to the women who were interviewed.
Photographing daily life of Bolivian women provided visual evidence for the research. I conclude that there is a huge separation between
classes, and ethnicities of women within Bolivia in relation to their opinions, and willingness to talk about their views on the role of men in
society. I also conclude that Bolivian women acknowledge that machismo is prevalent in their society and that they view that as negative, but
they do not know what to do about it and feel powerless. In the future I hope to educate and raise the awareness of Washington University
students on this issue.
CASPASE-9: A CANDIDATE SUSCEPTIBILITY FACTOR FOR MURINE ALKYLATOR-INDUCED LEUKEMIA
Yedda Li
Mentor: Timothy A. Graubert
Therapy-related acute myeloid leukemia (tAML) is caused by exposure to chemotherapies and radiotherapies and has a poor prognosis. To
better understand the genetic factors involved in secondary leukemogenesis, we performed murine genome-wide mRNA profiling and found
that differential expression of apoptosis-related genes was correlated with strain-dependent differences in tAML susceptibility. We identified
a 1,725-bp copy number variant (CNV) loss on chromosome 4 of the DBA/2J and PL/J strains that correlates with altered Caspase-9 (Casp9)
expression levels in hematopoietic stem/progenitor cells. Casp9 is a gene downstream from extrinsic and intrinsic death-inducing signals crucial
for the initiation of cellular apoptosis, and we propose that it may be an important factor influencing tAML susceptibility. In these strains,
Casp9 expression is undetectable in flow sorted kit+/lineage- (KL) hematopoietic stem/progenitor cells as measured by microarray profiling,
and confirmed in independent qRT-PCR assays. Full-length Casp9 cDNA clones could be isolated from mRNA libraries prepared from
DBA/2J and PL/J KL cells, but 35% of the transcripts were a novel isoform lacking exon 2 that results in a frameshift and an early stop codon
in exon 4. This premature termination codon is predicted to trigger nonsense-mediated mRNA decay, leading to the degradation of the novel
isoform and thus accounting for the low Casp9 expression levels in DBA/2J and PL/J. We hypothesize that cells with relatively low Casp9
expression would be more resistant to alkylator-induced apoptosis and more likely to accumulate mutations that initiate leukemias.
Preliminary data from flow cytometric apoptosis assays in KL cells after treatment with ENU, an alkylating agent, show a 45.4%±1.4% and
72.61%±2.6% decrease in AnnexinV+ cells in PL/J and DBA/2J, respectively, compared to C57BL/6J cells with normal Casp9 expression.
This shows that PL/J and DBA/2J cells are more resistant to ENU-induced apoptosis, suggesting that differences in Casp9 expression levels
may indeed play a role in influencing individual susceptibility to tAML. Ultimately, our understanding of the role that genetics plays in
determining susceptibility to secondary leukemias may allow us to define a process by which individuals who are more susceptible can be
successfully identified and screened from potential treatments that are known to induce these cancers.
SOOT INCEPTION IN GASEOUS COUNTERFLOW DIFFUSION FLAMES UNDER
OXYGEN ENHANCED CONDITIONS
Sydnie Lieb
Mentor: Richard Axelbaum
Due to the negative effects that soot has on health and the environment there is significant interest in reducing or eliminating its production
during the combustion of carbon-based fuels. Soot free flames, known as permanently blue flames, have been observed experimentally;
however there is debate regarding the physical explanation of these flames. Previously conducted computational work suggests that these
flames result from a change in the activation energy of a key soot formation reaction during oxygen enhanced combustion. This work uses
a one-dimensional gaseous laminar diffusion flame to study the experimental phenomena correlated with the computational results. The data
show that in oxygen rich environments the activation energy associated the formation reaction drops to zero. This is an important result
because it implies that the formation of soot is independent of temperature under these conditions. For a flame burning in air conditions,
soot formation increases as the temperature increases; however in the oxygen rich environment the temperature can be increased without the
onset of soot inception.
14
AN ANALYSIS OF HEAD MOTION FACTORS IN A PHARMACOLOGICAL STUDY OF
CORTICAL FUNCTION IN TOURETTE SYNDROME
Miranda Lindburg
Mentor: Kevin Black
REGIONAL VARIATIONS IN STIFFNESS ACROSS THE GASTRULATING CHICK EMBRYO
Stephanie Lindsey
Mentor: Larry Taber
Mechanical processes are at the basis of development, shaping the embryo and organs in order to give rise to the organisms we see today. Yet,
the physics behind these processes remains largely uncertain. Biomechanics has focused on the mechanics of sub-cellular structures and of
the mechanical properties of adult tissues but has largely passed over embryonic tissue-scale mechanics. In large part this overlook is due to
the fact that only a few devices have been designed to investigate the delicacy of embryonic tissues. We have used micro-indentation
experiments to examine the mechanical properties of the early stage chick embryo. In particular, we have examined HH stage 5 and 6
embryos paying particular interest to Hensen’s node, regions within the neural plate and regions just outside the neural plate, anterior to the
headfold formation. Knowledge of applied forces and deformation allows us to quantify the viscous and elastic properties of these tissues.
Results indicate regional variations in stiffness evolve over time.
RESIDENT EVIL 5’S OTHER ANTAGONIST
Robert Ling, III
Mentor: Abigail Horne
Capcom’s promotional trailer for their 2009 video game Resident Evil 5 prominently features racially-charged imagery: black children leering
from the shadows of a shantytown; a small gang of black men chasing a terrified white woman; a crowd of black men and women working
itself into a riot, communicating in barks and grunts. The game attributes the increased aggression of the black villagers to a viral infection,
but the imagery hews so closely to a Colonial tradition of negative stereotypes that many critics wondered: does the game encourage a fear
of black people? The philosophical approach produces mixed results: Plato, Aristotle, and contemporary philosophers disagree on the cathartic
potential of art depicting negative images to enlighten. The empirical approach, tracking consumption of violent games against commission
of violent acts, suggests that the game encourages compassion—or at least placation. This project’s examination of the cathartic value of games
informs the critics’ approach to the medium, as well as the responsibility of a producer in the medium.
FICTIONAL PRESIDENTS AND THEIR INFLUENCE ON THE AMERICAN PEOPLE
Evan Lobell
Mentor: Peter Kastor
OPTIMUM FLOATING AUTGYRO WIND TURBINE
Jessica Loyet
Mentor: David A. Peters
Atmospheric scientist Ken Caldeira calculated that if we were able to tap into just 1% of the energy stored in high altitude winds, we could
provide enough energy to power the entire Earth. One technology that may be used to harvest this energy is autogyros. An autogyro, first
successfully flown in 1923, is a rotorcraft similar to a helicopter that uses the upwards flow of air created during flight to turn its freespinning rotors to provide lift for the vehicle. I worked on a system of four autogyros attached to a frame that can be flown like a kite, 10,000
feet in the air. Not only is this system designed to operate at higher efficiency levels than other windmills, but it will also cause significantly
less environmental damage. Design graphs to determine the optimum efficiency of different systems were produced in this work.
15
CLONING EPHRIN GENES USING LIGASE-FREE METHODS
Bridgette Martinak
Mentor: Joshua Maurer
Ephrin genes encode for proteins that guide retinal axons to their final locations in the brain. Three Ephrin genes from the IMAGE consortium,
a cDNA library, were cloned from mice. The expressed proteins will be placed in gradients on self assembled monolayers (SAMs). Neurons
will then be cultured on these SAMs, with the intent of studying how neural growth is influenced by the Ephrin guidance cues.
The size of a DNA vector insert plays an important role in the cloning method used. During transformation, the vector inserts must find
both ends of the cut vector and be correctly attached. As insert size increases, the DNA experiences more difficulty circularizing. This process
becomes extremely difficult when using ligation methods.
In order to alleviate the difficulties associated with ligation, the Ek-LIC cloning method was utilized to clone the Ephrin genes. The
Ek-LIC cloning method should be an efficient and high-yielding method, even for large inserts. The pTriEx-5 vector was chosen for its many
advantages, including triple protein expression capabilities (bacterial, insect, and mammalian) that allow us to study the post-translational
modifications of mammalian proteins, as well as the ability to use multiple purification tags.
INVESTIGATIONS OF HOW CHEMICAL REACTIONS WITH INJECTED CO2 ALTER THE
GEOPHYSICAL PROPERTIES OF SEQUESTRATION SITES
Ryan Matos
Mentor: Young-Shin Jun
A set of incubation experiments with deep saline aquifer field site rock samples and acidified saline solutions was conducted at atmospheric
pressure and a temperature of 80 °C. The field site rock samples, a shale cap rock and a coarse sandstone, are intrinsic to the makeup of deep
saline aquifers and require study for carbon sequestration to be a viable option. These saline solutions, intended to mimic aquifer fluids after
CO2 injection, varied in ionic strength of NaCl and in pH. After incubations of the rock samples with the simulated solutions for durations
that ranged from fifteen minutes to two weeks, the solutions were measured using inductively-coupled plasma mass spectrometry. Results
showed that concentrations of potassium and calcium ions increased over time for incubated cap rock samples, representing an ion exchange
between K+, Ca2+, and Na+ ions and an alteration of the cap rock chemistry. The cap rock and sandstone samples were also analyzed postincubation using the BET gas adsorption method and x-ray diffraction. These analyses indicated changes in the reactive surface area of the
cap rock sample and elucidated potential formation of secondary minerals. Further research is required to improve understanding of the
dissolution and precipitation reactions innate to CO2 injection into deep saline aquifers and these reactions’ effects on the cap rock
chemistry and mineralogy. This work provided fundamental information regarding the reactions at mineral-carbonated saline water
interfaces at high temperatures and helped lay the groundwork for continued investigation.
HELIUM-3 NEUTRON PRECISION POLARIMETRY
Christopher Menard
Mentor: Christopher Crawford, University of Kentucky
Measuring neutron polarization to a high degree of precision is critical for the next generation of neutron decay correlation experiments.
Polarized neutrons are also used in experiments to probe the hadronic weak interaction which contributes a small portion (~10-7) of the force
between nucleons. Using a beam of cold neutrons at Los Alamos Neutron Science Center (LANSCE), we polarized neutrons and measured
their absolute polarization to ~0.1%. Neutrons were polarized by passing them through a 3He spin filter, relying on the maximally spin
dependent 3He neutron absorption cross section. The neutron polarization can be determined by measuring the wavelength-dependent
neutron transmission through the 3He cell. An independent measurement of the neutron polarization was also obtained by passing the
polarized beam through an RF spin flipper and a second polarized 3He cell, used as an analyzer. To measure the efficiency of the spin flipper,
the same measurements were made after reversing the 3He polarization in the polarizer by using NMR techniques (adiabatic fast passage).
We will show the consistency of these two measurements and the resulting precision of neutron polarimetry using these techniques.
IMPROVED PHOTOSYNTHETIC PRODUCTIVITY FOR RHODOBACTER SPHAEROIDES VIA
SYNTHETIC REGULATION OF THE LIGHT HARVESTING ANTENNA LH2
Alice Meng
Mentor: Robert Blankenship
Photosynthetic light harvesting antennas function to collect light and transfer energy to a reaction center for photochemistry. Phototrophs
evolved large antennas to compete for photons in natural environments where light is scarce. Consequently, cells at the surface of
16
photobioreactors over-absorb light, leading to attenuated photobioreactor light penetration and starving cells on the interior of photons. This
reduction of photosynthetic productivity has been identified as the primary impediment to improving photobioreactor efficiency. While
reduction of antenna size improves photosynthetic productivity, current approaches to this end uniformly truncate antennas and are difficult
to manipulate from the perspective of bioengineering. We aim to create a modifiable system to optimize antenna size throughout the bioreactor
by utilizing a synthetic regulatory mechanism that correlates expression of the pucB/A LH2 antenna genes with incident light intensity. This
new application of synthetic biology serves to transform the science of antenna reduction into the engineering of antenna optimization.
ARE NATURAL STATES LESS RESILIENT? A TEST OF THE NORTH, WALLIS AND WEINGAST THESIS
Jon Millis
Mentor: Lee Benham
In their book Violence and Social Orders, North, Wallace and Weingast propose a new theory of economic development. Central to their
argument is the classification of countries into “natural states” and “open access orders.” One important implication of their theory is that
open access orders are more resilient than natural states. This work examines this thesis for the 2008-2009 episode of financial shock by tracing
the volatility of currencies over the period. Implementing the Euro as a benchmark, I examine currency fluctuations in 102 different
countries. Open access orders should exhibit greater financial stability, as measured by the annualized standard deviation of percent change
in daily price of a currency. Low values suggest low volatility—and hence, high resilience—to economic shock.
ANALYSIS OF FOURTH CHROMOSOME HOST AND TRANSGENE EXPRESSION
IN DROSOPHILA MELANOGASTER
Perry Morocco
Mentor: Sarah Elgin
The fourth chromosome of Drosophila melanogaster is unique in that it possesses a high gene density within a heterochromatic chromatin
structure, simultaneously exhibiting features of euchromatin and heterochromatin. If the chromatin structure of the fourth chromosome is
assayed with transgene reporters, lines with fully active reporter genes and lines with variegating (partially silenced) reporter genes are recovered,
implying a difference in chromosomal packaging at the insertion site. Simplistically, one could expect that when the host gene is being actively
transcribed, the reporter should also be transcribed; similarly, silencing might be correlated. By analyzing the fourth chromosome reporters,
we can determine how the expression of the host gene influences reporter expression. Quantitative-PCR was used to assay the expression levels
of the host gene and the reporter in five fly lines at different developmental stages. As expected, lines with active reporters showed significantly
more transcription of the reporter than variegating lines; however, the results show only a weak correlation between the expression level of
the reporter and the host gene. This implies a chromatin environment that silences the reporter, yet allows for fourth chromosome host gene
expression, suggesting special properties of the latter genes.
DOUBLE PROBABILITY DISCOUNTING WITH GAINS
Joshua Morris
Mentor: Leonard Green
Individuals discount probabilistic rewards according to the hyperboloid function: V=A/(1+bX)s, where V is the present, subjective value of a
reward of amount A, X is the odds against it being received, b is a parameter that determines the rate at which the subjective value decreases,
and s represents the non-linear scaling of amount or probability. The subjective value of a probabilistic reward is typically measured by finding
the indifferent point between the larger probabilistic reward and a smaller certain reward. The goal of the current study was to add a
common ratio to the probability of receiving the larger reward and to the probability of receiving the smaller reward. In essence, indifference
points were now found for the larger probabilistic rewards in terms of a “less probabilistic” valuation. In two studies, participants discounted
several probabilistic amounts ranging from $250 to $2 million, several probabilities ranging from .8 to .05, and several common ratios
ranging from 1.0 to .05. Magnitude effects were evident for the discounting functions of the highest common ratios, but were not apparent
at the extreme low common ratios. Furthermore, the inclusion of common ratios led to decreases in the rate of discounting at the extreme
low common ratios, but had little effect on the rate of discounting at the medium to high common ratios.
17
THE ACTIVITY AND RATE OF THE ENZYMATIC REACTION OF ISONITRILE HYDRATASE
Ruth Nan
Mentor: Mark Wilson, University of Lincoln-Nebraska
Isonitrile hydratase (INH) is an enzyme found in the soil degrading bacteria, Pseudomonas putida. It catalyzes the hydration of isonitrile to
the corresponding N-substituted formamide, degrading the N≡C triple bond of isonitriles. The main role of INH in P. putida seems to be
detoxification – the isocyanide reacts completely to yield formamide. Isonitriles are highly toxic, and some organisms produce isocyanocompounds which are used to protect them from their enemies. It has been previously shown by UV spectroscopy that INH catalyzes the
formation of naphthyl formamide from naphthyl isocyanide. Fluorescence spectrophotometry confirmed this reaction and showed that the
reverse rate of INH is negligible.
The enzymatic activity of INH was confirmed and the catalytic rate determined. The function of the water molecule at the active site
between the cysteine and the aspartic acid residue on the enzyme was tested by making a D17E mutation, converting the aspartic acid, D,
into a glutamic acid, E, residue. Since glutamic acid is larger than aspartic acid by one methyl group, the mutation did not leave sufficient
space for a water molecule at the active site and deactivated INH, revealing that the mechanism for catalyzing the decomposition of
isonitriles requires the particular water molecule seen in the active site.
HARNESSING INNER WISDOM, FINDING HEALTH AND HAPPINESS:
MICHAEL POLLAN AND HEALTH BEHAVIOR CHANGE COMMUNICATION
Akhila Narla
Mentor: Melinda Mahr
In an intersection of the humanities and public health, journalist Michael Pollan shows us how effective nutrition behavior change
communication can stem from a written format. Using mantras like: “Eat food. Not too much. Mostly Plants,” Pollan creatively uses rhetorical
writing tools to incite healthy decision-making among his readers. In his essay entitled “Unhappy Meals” that appeared in the January 28,
2007, Sunday New York Times Magazine, Pollan uses devices like conversational tone and repetitive conclusive reasoning to allow readers to
use what they know to be true to make consistent healthy decisions. With ever-prevalent nutritional messages conveying contradictory
suggestions, Pollan’s essay proves valuable with its unique style and integration of the social, historical, and political factors contributing to
a readers’ need to convert knowledge to wisdom. The demonstrated efficacy of devices used in “Unhappy Meals” can serve as a basis for other
health behavior change communication appearing as a written work, including works that cater to diversified audiences, as it appears
audiences can be unified by their intent in reading a piece.
NRF TECHNICAL CORE: CONTROLLED SYNTHESIS OF METALLIC NANOSTRUCTURES
Kyle Oetjen
Mentor: Yujie Xiong
Over the past decade, metallic nanostructures have been widely used not only for fundamental research but also for practical uses in our lives.
The research community has yet to unlock the huge potential in these nanostructures with reliable and precise controlling means in their
production process. At the Washington University Nano Research Facility (NRF), we are able to control the shape, size, structure, composition,
surface group, and surface charge of metallic nanostructures, leading to the feasibility of finely controlling their properties and functions and
fully exploiting their applications or investigating their implications.
ANALYSIS OF WM TRACT INTEGRITY ASSOCIATED WITH THE VENTROMEDIAL
PREFRONTAL CORTEX IN CHILDREN WITH MAJOR DEPRESSION
Neil O’Kelly
Mentor: Kelly Botteron
This project is an extension of a previous investigation involving early onset major depression in children and adolescents. In that study the
volume of gray matter in several regions of the brain including the ventromedial prefrontal cortex (VMPFC) were measured. There were two
alterations in this project. Here we analyzed the white matter (WM) tracts rather than grey matter of the ventromedial prefrontal cortex, and
measured properties reflecting the integrity of the white matter: fractional anisotropy and mean diffusivity (obtained from diffusion tensor
imaging (DTI) scans) rather than volume. We hypothesize that early onset major depression affects white matter connections near the
ventromedial prefrontal cortex, a known region of interest.
18
SYSTEM FOR THE MICROFLUIDIC SYNTHESIS OF RADIOMETAL-LABELED BIOMOLECULES
Birce Onal
Mentor: David Reichert
The synthesis of radiometal-based Positron Emission Tomography imaging agents occurs through (a) the binding of a bifunctional chelator
to a biomolecule that targets cancer antigens, and (b) the chelation reaction of a radioactive metal ion by the bifunctional chelator. Currently,
inefficient mixing and the use of large volumes results in waste products and inefficient production of agents. Microreactors, systems of
micron(sub-millimeter)-scale channels into which liquid reagents are introduced and allowed to react, have been used to improve mixing of
reagents. A system utilizing a LabVIEW VI, automated pumps, and syringes, was developed to produce PET imaging agents in a micoreactor.
Upon entering the buffer, radiometal, and ligand required to complete the second reaction into a microreactor, improved mixing was observed
through Thin Layer Chromatography. These results will elucidate methods of producing radiometal PET agents on a small and efficient scale.
GLUCOCORTICOID REGULATION OF PER 2 RHYTHMS IN THE MOUSE FOREBRAIN
Chiamaka Onwuzurike
Mentor: Erik Herzog
The mammalian circadian (24hr) internal clock regulates many different processes including metabolism, physical activity and stress-associated
emotional processing. The strong correlation that exists between disruption in circadian clock rhythms and human psychiatric disorders, such
as Major Depression and Seasonal Affective Disorder, in addition to other experimental findings, suggests that normal circadian rhythms may
be necessary for normal mood regulation.
In light of this, we want to examine the precise cellular and molecular mechanisms that control circadian emotional behavior. Previous
research has shown that the expression of Period2 (Per2), a circadian clock protein, in the basolateral amygdala (BLA), central nucleus of the
amygdala (CeA), and bed nucleus of the stria terminalis (BnST) relies on a functioning suprachiasmatic nucleus (SCN), the master circadian
clock. It has also been previously determined that SCN-regulated release of glucocorticoids (GCs) from the adrenal glands regulate Per2
rhythms in the CeA and BnST, while the BLA is most likely controlled directly by the SCN.
Currently, nothing is known about the anatomical location of GC regulation of the CeA and BnST Per2 rhythms. In order to analyze the
many regulatory pathway possibilities, a genetically altered mouse model was used with glucocorticoid receptors (GR) knocked out in most
of the forebrain, namely the BLA and BnST, but with normal GR expression in the CeA. We stained the brains of knockout and wildtype
mice at four time points (ZT1, ZT7, ZT13, ZT19) and are currently working on the data analysis.
SNCC AND FRIENDS: THROUGH RADICALIZATION AND SEPARATISM
Dustin Palmer
Mentor: Krister Knapp
This project explores the intragroup conflicts and eventual decline of the Student Nonviolent Coordinating Committeee (SNCC), the “shock
troops of the Civil Rights Movement.” The focus is on SNCC’s relationship with an informal support network in the North, characterized
by “Friends of SNCC” groups. I hypothesize that SNCC’s increasingly caustic public persona and separatism impaired Friends of SNCC
groups’ ability to effectively fundraise, hastening the abrupt decline and disappearance of SNCC.
ECONOMIC ANALYSIS OF MICROHYDROPOWER IN ICELAND
Troy J. Pepping
Mentor: Dave Timmons, Study Abroad Institute
This research seeks to analysize the impact of microhydropower installations in Iceland based on economic and environmental costs and
benefits. Using a methodology similar to that applied in cost-benefit analysis, a case study in Ísafjörður demonstrates how residents can project
the overall impact of building a microhydropower installation and how the benefits of doing so compare to the costs. Based on the data
available and following several assumptions, a microhydropower installation modeled after an exisiting one in Ísafjörður would require a large
initial capital cost that eventually pays for itself over the course of the lifetime of the system. This research project was part of a larger study
inwhich each project focused on a different way that renewable energy technology could be applied in Ísafjörður based on local resources.
19
USING RING-EXCHANGE OPERATORS TO EXPRESS A HAMILTONIAN
WITH A SPIN LIQUID GROUND STATE
Jackson Pitts
Mentor: Alexander Seidel
Spin liquids are phases of matter which are noteworthy for the fact that they do not spontaneously break symmetry at zero temperature. In
a sense they are “more quantum” since the zero point energy successfully removes long-range ordering. This property of spin liquids may
provide the key to high-temperature superconductivity and is deeply related to the “topological quantum order” which may have applications
in quantum computing. One Hamiltonian was recently identified that describes a spin liquid phase on a 2D kagome lattice, and whose
ground state is exactly known. Unfortunately the Hamiltonian is currently defined very implicitly. To understand the Hamiltonian better, it
is desirable to express it in a basis of so-called “ring-exchange operators.” These operators act on a cell of the lattice by permuting the spins.
Unfortunately there is no unique way to realize such an expansion since general ring-exchange operators are vastly over-complete. The aim
of this project is to find a natural and simple subset of these ring-exchange operators, and to expand the Hamiltonian in this basis. The
expanded Hamiltonian may allow aid to anticipate any real materials which might have these properties.
THE RELATION OF VMPFC AND INSULAR CORTEX TO THE LONGITUDINAL COURSE OF ILLNESS
IN EARLY ONSET MAJOR DEPRESSION
Eric Potter
Mentor: Kelly Botteron
Changes in volumes of cortical structures, like the Ventra Medial Prefrontal Cortex and the Insular Cortex, have been implicated in Major
Depressive Disorder. The results of Magnetic Resonance Imaging (MRI) illustrate a possible correlation between cortical structure and specific
disorders or symptom cluster. The Insular Cortex is highly effective in maintaining sustainable emotion and sensory processes. Damaged or
impaired Insula have been shown to contribute to or allow MDD to occur. The goal of this work was to document the change in regional
cortical structure from the subject’s first baseline scans compared with periodic scans taken during the longitudinal course of the study.
The Botteron lab has recruited a sample population of 95 female, right handed, monozygotic and dizygotic twin pairs between the ages
of 13 and 23 where at least one twin meets diagnostic criteria for MDD according to the DSM-IV. Established diagnostic interviews have
been administered to the subjects to ascertain Axis I diagnoses. The insular cortex has been isolated in the averaged 3D T1-weighted
MPRAGE (1 mm isotropic voxels) MRI images using the image processing program ANALYZE that compiles 3D renderings of the Insula from
the segmentations for volumetric analysis. The boundaries of the Insular Cortex are defined with frequent reference to axial and coronal images.
THE BATTLE FOR THE MIND OF MAN:
JUSTIN MARTYR, DEMONOLOGY AND LATE ANTIQUE RELIGION
Travis Proctor
Mentor: Roshan Abraham
This research focuses on the demonology of Justin Martyr’s 1 Apology. The work displays Justin’s complex take on the presence and activity
of demons within the cosmological hierarchy. Throughout 1 Apology, Justin invokes the demons both as inspirations for evil activity and as
explanations for the hindering of the Gospel. The research explores the sources for 2nd Century conceptions of demons and Justin’s
application of his demonology in his apologetic agenda. Through this research, I examine 2nd Century Christian cosmology and how the
fledgling religion fits into the “locative” and “utopian” frameworks as defined by Peter Brown and J.Z. Smith in their respective works,
The Making of Late Antiquity and Map is Not Territory.
MULTIDISCIPLINARY APPROACH TO URBAN FOOD ACCESS
Sara Rasmussen
Mentor: Peter Benson
There has never been a more important time to understand access to food in the United States, as food has never been as abundant as it is
for Americans living today. With thousands of 24-hour-a-day restaurants, gas stations, and vending machines across the country, most
Americans can easily access cheap and prepared food all hours of the day. Most Americans have no problem accessing food—the problem
lies in accessing healthy food, a problem that disproportionately affects low-income populations. Low income population’s lack of access to
healthy food, particularly fresh produce, has been well documented by different disciplines, including anthropology, public health, history,
sociology, political science, medical geography, and nutrition. Each of these disciplines provides a different understanding of access to healthy
food. This study takes a multidisciplinary approach to create a more complete understanding of access to food.
20
CONSTRUCTION OF A TEM RESONATOR FOR BRAIN MRI
Laura Rayhel
Mentor: Mark Conradi
In a nuclear magnetic resonance (NMR) experiment or imaging session, a short radio-frequency electromagnetic pulse causes the precession
that produces the information or image. The device that creates this wave pulse is called an NMR “coil,” a series of one or many circuits
tuned to a specific frequency depending on the particular sample to be imaged. Researchers at Washington University Medical School needed
a coil for imaging experiments on ex vivo human brains. This project was to build a specific type of coil design, called a birdcage coil, which
could accommodate an entire brain at one time for these experiments. It needed to be large enough to fit the whole brain and able to create
a pulse field homogeneous enough to produce a high-resolution image. A coil consisting of 24 tuned circuits arranged around the circumference
of an eighteen-inch-long, eight-inch diameter Plexiglas tube was constructed. This coil could create an image with good enough resolution
for the imaging experiments; it is now being used to image and study the brains of U.S. soldiers who died of massive head traumas.
HUMANITIES DIGITAL WORKSHOP: THE SPENSER PROJECT
Cecilia Razak
Mentor: Joseph Loewenstein
The Spenser Archive is the digital component of Oxford University Press’s forthcoming The Collected Works of Edmund Spenser.
ANALYSIS OF A FRAME AS A SUBSTITUTE STIMULUS FOR
THE ROD AND FRAME EFFECT
Fady Riad
Mentor: Dora Angelaki
One of the most interesting and pertinent areas of study in neuroscience is the ability to perceive spatial orientation, a multisensory task that
requires integration from many sensory systems. It is of special interest to study how the brain integrates multisensory information when
different senses provide conflicting information. For example, in an airplane that is pitched and accelerating upward, conflicting vestibular
and visual information must be resolved by the brain, resulting in a weighted compromise based on the reliability of each input. These
“compromises” are not always accurate to life and the need to consider them has been implicated when developing new technology,
particularly regarding flight.
Previous experiments have shown that when a bar of light is enclosed in a visual frame, subjects make consistent errors when trying to set
the bar vertically. This effect demonstrates the effect of our visual surroundings on our visually perceived vertical (VPV) and is called the Rod
and Frame Effect. Additionally, subjects have been observed to make similar mistakes when the same bar is presented to a tilted subject against
no backdrop. This demonstrates the variability in our vestibular estimations and has been attributed to the effect of a “prior,” a tendency in
our estimates based on intrinsic or acquired knowledge about the world. A rich body of knowledge has been developed describing these two
effects and their interactions with each other, but no inquiry has yet been made as to the effect of the stimulus itself. The present research
aims to study the ability of subjects to align full visual scenes, rather than a bar, to the vertical. Subjects will be asked to set a visual bar to
vertical under different tilts for our control experiment. They will then be asked to set an entire tunnel vertically under the same tilt
conditions. As such, the visual contribution of the stimulus itself, as well as its interaction with vestibular signals, will be explored. Ultimately,
this study will be the ground work for single unit recording experiments which will help identify the exact regions in the brain responsible
for spatial orientation and perception.
USING LIGAND-BASED VIRTUAL SCREENING TO MODULATE
RHODOPSIN-TRANSDUCIN INTERACTION
Nicole B. Rockweiler
Mentor: Garland R. Marshall
G-protein coupled receptors (GPCRs) comprise a large protein family that plays an important role in many physiological and pathological
processes. Modulation of the interaction between activated GPCRs and their respective G-proteins is an attractive paradigm for the treatment
of certain congenital diseases that cause constitutive activation. Typically, the interaction between a GPCR and its respective G-protein is
modulated by blocking agonist binding to the extracellular region of the GPCR. A relatively unexplored method is to block the G-protein
from binding to the GPCR on the intracellular side. A ligand-based approach was used to find compounds that modulate the interaction
between rhodopsin, a GPCR involved in vision, and transducin, its G-protein. A pharmacophore was generated from a tetrazole peptidomimetic
designed to stabilize the photoactivated state of rhodopsin. The Maybridge Hitfinder and National Cancer Institute (NCI) Diversity small
21
molecule libraries were screened for compounds containing the pharmacophore using UNITY, a search program in SYBYL. Forty-seven
compounds resulted from the Maybridge library, and none resulted from the NCI library. These compounds were tested experimentally for
their ability to stabilize Meta II (MII), one of the photoactivated states of rhodopsin. Five of these compounds were found to stabilize the
MII state (an 11% hit rate), with EC50 values ranging from 0.593 to 1.8 mM. Four of these confirmed MII stabilization with acid trapping
assays. Binding and release assays were performed to determine if the small molecules inhibited transducin from binding to photoactivated
rhodopsin. The compounds found in this study are promising starting points for subsequent optimization for possible therapeutics to treat
congenital retinal diseases, such as retinitis pigmentosa.
THE VENEZUELAN DEMOCRATIC DICTATORSHIP:
HUGO CHAVEZ AND THE RISE OF TWENTY-FIRST CENTURY SOCIALISM IN LATIN AMERICA
Alyse Rooks
Mentor: Ignacio Sanchez Prado
On February 15, 2009 the Venezuelan people voted on a referendum to end Presidential term limits, thereby making it possible for current
Venezuelan President Hugo Chávez to run for re-election indefinitely. Inspired by this event, this study focuses on two aspects of Chávez’s
career. Firstly, it investigates the shift in Chavismo, which is a socio-political movement that revolves around Chávez’s political positions. This
portion of the study explores the transition from the idealistic, Simón Bolívar-focused phenomenon to twenty-first century socialism.
Secondly, the study examines the impact that Chavismo and twenty-first century socialism have had on the rest of Latin America. This
researched showed that Chávez has greatly influenced other Latin American leaders by providing an alternative to the unsuccessful neoliberal policies that have plagued Latin America. Chávez’s twenty-first century socialism represents a Latin American solution. Furthermore,
Chávez has also become a ringleader for leaders around the world. Chávez has become the symbol of anti-globalization and anti-U.S.
sentiments. Despite his controversial persona and his distaste for political niceties, Chávez continues to be politically successful in Venezuela.
Ultimately, the passing of the re-election referendum has solidified Chávez’s power while bringing Chávez one step closer to successfully
implementing twenty-first century socialism.
UNCOVERING THE REAL LOLITA
Matthew Rosenfeld
Mentor: Bethany Daniels
Are men sexually satisfied with woman’s expression of the ideal female physique? Do their opinions matter? How do certain style trends work
for or against this topical ideal? Much of this research stems from an extremely explorative and theoretical approach. Gender issues, the
fashion industry, and Vladimir Nabokov’s Lolita were three somewhat disparate modes of intrigue that came to reveal something about the
sexual relationship between men and women. For many years, women have been cast as subservient in our hierarchical culture and, even
today, there exists a kind of asymmetry in which the idea of female independence is subverted. Is this idea of dependence beginning to
change? John Berger’s Ways of Seeing and numerous psychological studies on body type preference served as lenses for this analysis and helped
unveil an interesting contradiction- on the average, men like women to be larger than women want to be. Why?
PREPARING A CRITICAL EDITION OF BRITTAIN’S IDA
Channah Rubin
Mentor: Joseph Loewenstein
The goal of this project is to prepare a comprehensive critical edition of Brittain’s Ida along with an accompanying essay on attribution in
early modern English literature using scans and collations of the six remaining printed witnesses of the work. The poem Brittain’s Ida, once
considered to be the writing of Edmond Spenser, has been attributed to Phineas Fletcher since the 19th century. This edition will become
part of the larger Spenser Edition prepared by the Spenser Project.
EXPLORING MOLECULAR DYNAMICS TECHNIQUES TO IMPROVE
BIOMOLECULAR STRUCTURES FOR NANODESIGN
Shubho Sadhu
Mentor: Bruce Shapiro, National Cancer Institute
Nanobiology researchers would like to evaluate nanostructures potentially consisting of millions of atoms before performing in vitro or in vivo
experiments. Molecular dynamics (MD) is a type of computer simulation currently capable of exploring the dynamic behavior of molecules on the order
22
of tens of thousands of atoms within reasonable time constraints. As nanostructures are designed to be larger, faster MD simulations are needed.
Amber is an MD program traditionally used to simulate biomolecular structures such as RNA. NAMD, a newer MD program, scales
better than Amber with increasing numbers of processors and yields comparable results. For example, a 31K-atom fully solvated RNA
system with 42 nucleotides (1358 atoms) takes approximately 39 hours to simulate 5 nanoseconds of real-time with NAMD and 52 hours
with Amber using 8 processors. In addition, NAMD can run on Nvidia graphics processing units (GPUs), which are often found in standard
desktop computers. The computational time with 2 CPUs and 2 GPUs is similar to 8 processors for a 31K-atom solvated RNA system with
NAMD. Therefore, GPU technology allows simulations to be run on standard workstations instead of expensive supercomputing clusters.
We present a comparison of NAMD and Amber benchmarks with different numbers of processors and the application of MD to simulating
RNA-based nanostructures.
IDENTIFICATION OF PA3920 AS THE PRIMARY SIL-LIKE SILVER RESISTANCE DETERMINANT
IN PSEUDOMONAS AERUGINOSA, MPAO1
Adam J. Salazar
Mentor: Carolyn Cannon
The sil operon consists of seven genetic determinants capable of conferring plasmid-based resistance to silver antimicrobials on otherwise
susceptible gram negative, enteric species. To assess the role chromosomal sil homologues play in modulating silver sensitivity in the gram
negative, non-enteric pathogen, Pseudomonas aeruginosa MPAO1, single gene MPAO1 transposon insertion mutants (sgTIMs) corresponding
to pBLAST identified sil homologues were tested for silver sensitivity by observing culture density in the presence and absence of silver
nitrate. Most sgTIMs showed nominal deviation from wild type sensitivity. However, a high sensitivity elevation phenotype was found for
the sil P homologue, PA3920, sgTIM. In trans recovery of wild type sensitivity via the generation of a plasmid expressing PA3920 and its
transformation into the PA3920 sgTIM demonstrates that PA3920, which encodes a known copper efflux, P-type metal binding ATPase, is
the primary sil-like mitigator of silver toxicity in P. aeruginosa. In order to establish that the Salmonella PA3920 homologue, sil P, is
similarly capable of recovering wild type MPAO1 silver sensitivity, a plasmid was constructed expressing sil P and transformed into the
PA3920 sgTIM. It was found that sil P is unable to restore wild type sensitivity, suggesting that sil P does not have native silver efflux
activity in Pseudomonas.
MOROCCAN STREET PERFORMERS: RENOVATORS OF PAST TRADITIONS
Stefan Santiago
Mentor: Younasse Tarbouni
Moroccan music has captured the minds of Europeans and Americans alike. Thanks to famous musicologists like Paul Bowles and Phillip D.
Schuyler, there has been extensive documentation of the traditional styles that occur across the country. In recent years within this vast
tradition, there has been a movement towards individualism and in surroundings where much of the music has occurred in a collective manner,
this is reason to investigate. I chose to look at the sphere of street musicians within Moroccan music as a whole. On one hand these performers
are adhering to traditions that have lasted for centuries, but on the other, they are breaking out of the molds of space and sound. Through
interviews with musicians and consultation on pre-written sources, I sought information on traditional music, recent trends in Moroccan
music, and general perceptions toward street performers. Though the trade is not exactly appreciated, it remains an important part of the
preservation of Moroccan folk music, while demonstrating the lasting effects of significant musical trends in modern years. The mix between
traditional setting and modern music, or vice-versa, is interesting and can illuminate the subsistence of folk music or acquiescence of new
music thanks to tourist industries and human ingenuity.
BELARUSIAN DEMOCRATIC PUZZLE
Viktoryia Schnose
Mentor: Margit Tavits
Some international opinion surveys rank Belarusians as among the most committed democrats in the former Soviet Union. At the same time
the current Belarusian regime has been labeled “the last dictatorship of Europe” and “an outpost of tyranny.” For many scholars Belarus
remains a puzzle: after the break-up of the USSR, despite the optimistic predictions and existing necessary preconditions, such as tolerance,
trust, political activism and post-materialist values, Belarus has rejected democracy and market reforms, submitting to the authoritative rule
of a charismatic populist leader A. Lukashenka. It stands in sharp contrast to its politically and economically prospering neighbors that have
joined the West through NATO and EU: Poland, Ukraine, and especially the Baltic States. So what has caused Belarus to “deviate” from the
promising path of democratic transition without any major opposition from its citizens and what are the prospects for democracy in the
future? Current democratization literature fails to explain this failure of democratic transition. I build a most-likely case study and show that
23
Belarus has failed to democratize due to interaction of economic and cultural factors, such as economic development and urbanization,
factors that have been previously thought to promote democratization.
CARBON DIOXIDE AND METHANE CONVERSION TO LIQUID FUEL
Brent Sherman
Mentor: Cynthia Lo
Rising atmospheric levels of carbon dioxide and methane contribute to global warming. While sequestration would reduce these levels, turning
the unwanted gases into a valuable product would be better. The direct conversion of carbon dioxide and methane to liquid fuels using an
integrated nanocatalyst of platinum on cerium oxide is the focus of this research. Using computer modeling, the nanocatalyst will be designed.
Preliminary results indicate strong chemisorption of methane onto platinum and weak physisorption of carbon dioxide onto stoichiometric ceria.
Previous work indicates that carbon dioxide will be strongly chemisorbed onto a reduced ceria surface, thus activating it for the desired reaction.
HIGH DIMENSIONALITY SCHEDULING TECHNIQUES FOR OPEN SOFT REAL-TIME SYSTEMS
Braden Sidoti
Mentor: Christopher Gill
Open soft real-time systems, such as mobile robots, must cope with unpredictable variables both effectively and efficiently. These systems
drastically differ from traditional real-time scheduling systems and need new underlying assumptions in its framework— a new model must
be created to address these systems more effectively. In previous work, a Markov Decision Process (MDP) was used to design scheduling
policies for open soft real-time systems subject to a utilization share goal. This technique produced optimal scheduling policies but became
too computationally intensive for scheduling more than four or five tasks. In reality, a system can easily have upwards of dozens of tasks making
this technique impractical. In this research we used a partitioned model to approximate an exact schedule and investigated parameter
optimization techniques. When compared to the greedy model, the partitioned model produces higher quality policies. Although we are not
able to compare policies generated by this new approach to truly optimal policies determined with a MDP, this new process is a step towards
an improved and practical scheduler for open soft real-time systems.
MAMAN IN CONTEXT
Emily Silber
Mentor: Rebecca DeRoo
The premise this thesis is an analysis of how Louise Bourgeois’ thirty-foot tall, bronze sculpture of a mother spider titled, Maman (1999)
operates within the context of the Louvre in Paris, France; The Guggenheim in Bilbao, Spain; The National Gallery of Art in Ottawa,
Canada; and The Tate Modern in London, England. Surveying these four locations, I took photographic and video documentation of their
varying aesthetic components, in addition to researching the cultural history of each respective museum and city. As can be expected, due to
the differences in appearance and social context of these sites, the viewer’s interaction with the sculpture is significantly altered. For example,
the unique, domineering, contemporary design of the Guggenheim juxtaposed with Maman’s bronze material and sculpted musculature
highlights its classic and traditional background. By comparison, Maman’s large scale and abstract representation of such alternative subject
matter as a mother spider feels highly current in context with the neat, symmetrical, classic architecture of the Louvre. It is my intent to
discuss the ways in which Maman interacts with each site in its exhibition of the timeless, universal and complex theme of motherhood.
BOLIVIAN IMMIGRATION AND ARGENTINA’S GARMENT INDUSTRY:
THE ROLE OF MIGRANT SOCIAL NETWORKS
Elizabeth Slater
Mentor: Bret Gustafson
Globalization and capitalism have had obvious impacts throughout the world. An increase in immigration between countries along with an
increase in immigrant laborers working in the informal sector of the economy is one such impact. While this phenomenon is not limited to
any single area of the world, it is clearly seen in Argentina, where there has been an influx of migrant workers from neighboring countries.
In the largest city in Argentina, Buenos Aires, Bolivian immigrants have created an economic niche working informally in the garment industry;
they have not only provided cheap labor for many garment sweatshop owners and for many well-known clothing manufacturers, but have
also taken advantage of the flexibility and informality of the industry to start their own small clothing factories, called talleres.
Through analyzing the personal narratives of a group Bolivian immigrants, this study tries to understand why these immigrants decided
24
to leave their home country of Bolivia and what processes they had to go through in order to find work in the garment industry in Buenos
Aires. This study concludes that migrant social networks play a crucial role in connecting immigrant laborers with jobs in the informal
sector of the economy. It also concludes that while these networks help to unify Bolivian immigrants culturally, they fall short of unifying
them economically or politically. Social networks help to form the foundation of migratory movements, but they do not necessarily have the
power to confront larger socioeconomic problems, such as a lack of regulation within the garment industry and an absence of labor rights
for Bolivian workers.
A STUDY OF LAND TENURE AND LIVELIHOODS OF THE OGLALA LAKOTA NATION
Joseph Stromberg
Mentor: Bret Gustafson
The Oglala Lakota Tribe of the Pine Ridge Indian Reservation in South Dakota is among the most marginalized and impoverished groups
in the present-day United States. Though they are a sovereign nation, a paternalistic history of federal land policy has led to 60% of the territory
on the reservation leased to or owned outright by non-Indians, rather than generating income for tribal members. Inadequate probate
procedures have fractionated most of the land still in Indian hands, frequently dividing an allotment between hundreds of owners. Indianoperated farms on Pine Ridge are under-capitalized and produce a fraction of the revenues of non-Indian farms on the reservation.
The research attempts to examine the links between policy, obstacles to land tenure, Oglala Lakota culture, and Lakota household
livelihoods. The case study used observant participation, participant interviews, and key informant interviews. In interviews, discussions focused
on families’ land allotments, land use, probate history, obstacles to development, and perspectives on tribal and federal land policy. The field
work on the Pine Ridge Reservation was conducted during June and July of 2009. Analysis of the information continues during the fall of 2009.
THE ROLE OF VIP NEURONS IN MOUSE CIRCADIAN RHYTHMS
Daniel Sun
Mentor: Erik Herzog
The mammalian suprachiasmatic nuclei (SCN), located in the anterior hypothalamus, are a master circadian pacemaker. These 20,000
heterogeneous neurons synchronize with each other to regulate daily rhythms in physiology and behavior. Elucidating the mechanisms
behind rhythm generation and synchrony between oscillators in the SCN is a crucial step in the study of disorders related to circadian
dysfunction, such as major depressive disorder and advanced phase sleep syndrome.
Recent studies implicate vasoactive intestinal polypeptide (VIP) as a candidate for generating and coordinating circadian rhythms in the
SCN. We hypothesized that VIP-expressing neurons are a class of pacemaking cells which drive and synchronize rhythms for the entire SCN.
To test this hypothesis, we generated a transgenic mouse model to specifically delete VIP neurons in the SCN upon exposure to the steroid
hormone, tamoxifen. This project involves (1) verifying that our transgenic model deletes VIP neurons in the SCN using immunohistochemistry,
and (2) analyzing locomotor data of VIP-cell-less mice. In our preliminary work, we have confirmed that VIP neurons die upon exposure to
tamoxifen in vitro and that our transgenic mice exhibit normal circadian behavior in the absence of tamoxifen. In future experiments, we
plan to delete VIP neurons of mice in vivo and analyze their changes in running wheel behavior.
HIV TREATMENT MODULATES GLOBAL RESTING CEREBRAL BLOOD FLOW IN HIV+ SUBJECTS
Jewell Thomas
Mentor: Beau Ances
Soon after infection, HIV enters the central nervous system by a so-called “Trojan horse” method. Previous cerebral perfusion studies have
shown that HIV causes lowered blood flow in specific cortical and subcortical regions in HIV positive (HIV+) individuals undergoing highly
active antiretroviral therapy (HAART) compared to non-infected (HIV-) controls. We hypothesized that, in a longitudinal and crossectional
study of HIV+ (naive), HIV+ (on HAART) and HIV- controls, HAART would lead to normalization in global resting cerebral blood flow
(rCBF) measures.
rCBF measures were acquired from 26 controls and 39 HIV+ subjects using an arterial spin labeling technique on a Siemens 3T scanner.
HIV+ subjects were subdivided into those who were naive to medications (n=19) and those undergoing HAART (n=20). Nine HIV+ naive
subjects were studied 3-5 months after starting medications.
No significant differences existed between groups in age, sex, or education. HIV+ individuals had a significantly higher viral load than
HIV- controls (p=.001). Overall, HIV- controls had a significantly higher global rCBF (61.7 ± 1.7 ml/100gm/min) compared to HIV+
participants (48.4 ± 1.9 ml/100gm/min). Global rCBF was significantly diminished in HIV+ naïve patients (44.8 ± 1.9 ml/100gm/min)
compared to HIV+ subjects on HAART (52.6 ± 2.0 ml/100gm/min). Longitudinally, every HIV+ naïve subject had a decrease in viral load
and an increase in rCBF after starting HAART.
25
PESTICIDE ALDICARB ADSORPTION ONTO SOIL DURING WATER REUSE:
FOURIER TRANSFORM INFRARED SPECTROSCOPY STUDY
Anca Timofte
Mentor: Young-Shin Jun
To address future water supply shortage due to climate changes, development of effective conservation strategies of sustainable water supplies
are required. A potential promising solution to prevent water shortage is the aquifer recharge with wastewater effluents. However, to perform
a more effective and safe operation of this process, a better understanding of the fate and transport of remaining pollutants, such as
pharmaceuticals or pesticides in the effluent is necessary. Aldicarb, a carbamate insecticide used on a wide range of crops, needs to be removed
from wastewater, if this is to be used to recharge fresh water aquifers. Our research project investigates the adsorption of aldicarb onto soil
as it flows through it, as it would in the recharging process. We aimed to identify which soil mineral components are most responsible for
aldicarb adsorption. We studied the interaction between aldicarb and different model minerals (which could be present in soil) individually—
aluminum oxide, iron oxide, manganese dioxide, calcite, and quartz— and field-collected soils. Using Diffuse Reflectance Fourier Transform
Spectroscopy to study the forming or breaking of bonds between aldicarb and model and field soils, we concluded that calcite and quartz are
responsible for aldicarb binding to soils. We also investigated the effect of humic and fulvic acids, naturally occurring organic matter found
in soil, on aldicarb adsorption. For this, we coated calcite and quartz with fulvic acid and humic acid and let the coated samples react with
aldicarb in a batch equilibrium experiment. Using the results of these experiments, we determined a quantitative contribution from quartz
and calcite to overall aldicarb adsorption and identified the functional groups of aldicarb responsible for binding to soil.
INVESTIGATING EFFECTS OF ISOFLURANE ON TRACER BINDING
Iboro Umana
Mentor: Joel Perlmutter
Parkinson disease (PD) is a neurodegenerative disorder characterized by loss of dopaminergic neurons in the substantia nigra. Currently, PD
research is actively focused on pathology of PD. To learn more about PD pathways, we need to have a research tool that allows us to study
PD progression. In our lab, we utilize PET radiotracers (FDOPA, DTBZ, and CFT) to accomplish this objective. Their binding potential
(BP) to striatal binding sites serves as an indicator of neurodegeneration in PD.
Recently, we have noticed that BP values appeared to be variable across baseline scans for several monkeys that we have studied. We
hypothesized that isoflurane, a general anesthetic, could be a contributing factor to BP variability. To test this hypothesis, we calculated
isoflurane exposure via several methods to determine if there was any relationship between isoflurane exposure and BP potential.
We found that isoflurane had a differential effect on PET radiotracers. FDOPA BP strongly correlated with isoflurane calculated from
time of injection and during scan time of interest. DTBZ and CFT BP did not demonstrate any relationship with isoflurane, but the power
of the sample needs to be increased to add further support to this claim.
PETERS PRACTICAL TIP CORRECTION PROCEDURE FOR APPLICATION TO COMPUTED LIFT
Jennifer Varriano
Mentor: David Peters
The use of the Prandtl tip-loss correction is quite common in the analysis of rotating wings. It is a correction factor between blade loading
(i.e., circulation) and the induced flow near the blade tip that accounts for the effects of a finite number of blades. This factor is placed on
the loading-to-inflow theory before it is coupled with blade-element theory in order to find the final inflow and loading distributions. With
proper correction, the inflow should be such that the loading goes to zero at the blade tip. However, sometimes it is useful to correct a
loading distribution after the fact (that is, after an inflow theory and lifting theory have been already coupled). Often the Prandtl correction
factor is used as the means to correct the blade loading and to insure that it goes to zero at the blade tip; but direct application of the factor
is not appropriate for such an application. In this project, we show how to make lift corrections to account for blade number after the
coupled lift-inflow distribution has been computed without the effect the blade number.
PROTECTIVE EFFECTS OF EPIDERMAL GROWTH FACTOR IN PNEUMONIA-INDUCED SEPSIS
Paul Vithayathil
Mentor: Craig Coopersmith
Epidermal growth factor (EGF) is a cytoprotective peptide that improves survival and decreases intestinal injury in non-infectious intestinal
injury models and in peritonitis-induced sepsis. The aim of this study was to determine if systemic administration of EGF following
pneumonia-induced sepsis improved gut integrity and survival. Pneumonia was induced by intratracheal injection of 40µL of Pseudomonas
26
aeruginosa (2-4 x 108 colony-forming units (CFU)) followed immediately by intraperitoneal injections of 150 µg/kg/day EGF or an
equivalent volume of saline for controls. At 24 hours, lung histology was scored in H&E slides, and apoptosis was determined by active
caspase-3 staining. Neutrophil activation was measured by myeloperoxidase assay of both lung tissue and Broncho Alveolar Lung Fluid.
Intestines were evaluated for changes in villus length, apoptosis by active caspase-3 and H&E staining, and proliferation by BrdU staining.
Systemic cytokines were measured in serum by multiplex array. EGF had no significant effects on lung histology and systemic cytokines.
However, EGF did return gut apoptosis and proliferation to sham levels. A separate group of mice were followed for survival. When given
immediately after surgery, EGF treatment improved survival from 35% in untreated septic mice to 90% in EGF-treated septic mice. When
delayed 24 hours, EGF treatment still provided a survival advantage of 73%. These results suggest there is an association between improved
gut integrity and survival in pneumonia-induced sepsis.
IDENTITY IN THE EMIRATES
Marcus Walton
Mentor: Yugeng Mao
Over the past few years, Dubai’s presence as an international economic hub has become substantiated in the global market. It’s political
relationships with large developing nations such as India and China has become an increasingly significant for the UAE as a whole. In light
of this, the issue of migrant workers in Dubai has become an important element surrounding these relations.
The purpose of this study is to examine the cultural, social, and political implications and the lifestyle of Chinese migrant workers in
Dubai. Furthermore, the study looks to analyze how this environment has changed in the recent global economic recession.
ACTIVATED ASTROCYTES MODULATE MICROGLIAL ACTIVATION IN APP/PS1 MICE
Yan Wang
Mentor: Jin-Moo Lee
Following amyloid plaque formation, reactive microglia and astrocytes accumulate around plaques. However, the role of reactive gliosis in
Alzheimer’s disease pathogenesis is poorly understood. We have recently found that deletion of reactive astrocyte genes, glial fibrillary
protein (gfap) and vimentin (vim) results in increased amyloid plaque load in APP/PS1 mice, suggesting that astrocyte activation may limit
amyloid plaque growth. Deletion of gfap and vim result in astrocytes which demonstrate attenuated activation in response to stress. In this
study, we sought to examine the interaction between activated astrocytes and microglia in this AD mouse model. Total microglia counts
(using Iba-1 immunohistochemistry) in APP/PS1 gfap+/+ vim+/+ (APP gv+) compared to APP/PS1 gfap-/- vim-/- (APP gv-) mice was not different
(63,758 microglia per mm2 in APP gv+ vs. 58,451 microglia per mm2 in APP gv-, p=0.28). However, the number of microglia adjacent to
plaques was higher in APP gv- mice compared to APP gv+ mice (1210 microglia per mm2 vs. 1780 microglia per mm2, p=0.0003), suggesting
that activated astrocytes regulate microglial redistribution. This redistribution was evident even when correcting for difference in plaque load
between the two genotypes (28,107 microglia per mm2 vs. 34,931 microglia per mm2, p=0.035). Conversely, the number of microglia
distant from plaques showed a trend for decrease (1,299 microglia per mm2 vs. 1,119 microglia per mm2, p=0.056). These data suggest that
activated astrocytes surrounding amyloid plaques may regulate the distribution of microglia during amyloid plaque pathogenesis.
THE PAST IS PRESENT:
SOCIO-RELIGIOUS CONTINUITY BETWEEN THE PRE- AND EARLY ISLAMIC ARABIAN PENINSULA
Nicholas Wilbar
Mento: Asad Ahmed
In broad terms, the project considers the socio-religious continuity between the pre- and early-Islamic communities on the Arabian Peninsula.
At first glance, the rise of Islam very obviously carved out a great many changes in the Arabian socio-religious landscape. As the project
concludes, however, the majority of these changes were of an outward rather than paradigmatic nature. They were the sort of changes wrought
by a modification of how one acts, but not by the modification of how one thinks about those actions. Thus, by extension the study
maintains that this is precisely the way in which the continuity between the pre- and early Islamic communities should be viewed. In the face
of a high degree of external change—modifications in ritual, name, custom and the like—there was an equally palpable degree of continuity
in perspective. To make a wildly anachronistic analogy, the rise of Islam didn’t erase what came before it; rather it cut, pasted and ultimately
reformatted it.
27
THE DEVELOPMENT OF SPECIFIC FEARS IN 3-TO-5-YEAR-OLDS
Lynn Wilkie
Mentor: Pascal Boyer
This project aims to investigate the difference between evolved fears, or fears that humans are programmed with at birth, and learned fears, or fears
that are adapted through experience and teaching. To do this I am working with children between the ages of three and five. The assumption is
that any fears found in the youngest children will be evolved, and any changes that are observed over the age span will be the result of learning.
These fears will be assessed through an indirect storybook method that has been originally designed for this project. I will be looking at two fears:
that of animals and that of social exclusion. For each fear two children’s books have been written, one that is meant to tap into the fear and one
that is meant to be relatively neutral. I read the stories to the children individually and then go back the next day and ask them to tell the story
back to me. The critical variable is the difference in memory between the two versions of the same story. I expect to find a decrease in fear for the
animal story and an increase in fear for the social exclusion story. If this is the case, it will suggest that fear for animals is innate but declines with
lack of experience, and that fear of being excluded is not innate and increases with more exposure to school and other social activities.
MAGNITUDE OF T-WAVE ALTERNANS ON POST MI HOLTER RECORDINGS AS A PREDICTOR OF
CARDIAC DEATH IN THE ENRICHD TRIAL
Austin Wilmot
Mentor: Phyllis Stein
T-wave alternans (TWA) is a beat-to-beat variation in the T wave of an electrocardiogram (ECG) linked to cardiac death. TWA is subtle
therefore computer analysis is required for measurement. In 120 patients taken from the ENRICHD (Enhancing Recovery in Coronary
Heart Disease) trial database, the relationship of TWA on Holters and subsequent cardiac death will be examined by level of depression at
the time of the recording (non-depressed, mild/moderately depressed, severely depressed). ENRICHD examined the effect of treatment of
depression on a combined endpoint of all cause mortality and nonfatal infarction in patients with recently diagnosed acute MI (myocardial
infarction). Cases and controls for our sub-study had Holter recordings in ENRICHD and were matched on age, gender and depression status.
All patients who died were included. Examining TWA will involve reloading 2-Channel Holter ECG recordings, performing Holter analysis
and TWA analysis via GE MARS software. Other questions to be explored include whether TWA is more common in people with
depression. If so, does it help explain increased cardiac death among depression patients? Our novel findings may include a connection
between TWA post-MI and cardiac death, as well as a mechanism to explain excess mortality among depressed post-MI patients.
REGULATION OF DOPAMINE RELEASE BY THE ENDOCANNABINOID SYSTEM
IN THE NUCLEUS ACCUMBENS CORE
Maxim Wolfson
Mentor: Margaret E. Rice, New York University
This work examined the regulation of locally evoked dopamine (DA) release by type 1 cannabinoid receptors (CB1Rs) in a forebrain region
important in reward processing, the nucleus accumbens (NAc) core. Using fast-scan cyclic voltammetry with carbon-fiber microelectrodes in
coronal slices of guinea pig striatum, stimulated increases in extracellular DA concentrations ([DA]o) could be directly monitored in the
presence of various pharmacological agents. Findings show a significant decrease in pulse-train evoked [DA]o with application of a CB1R
agonist WIN55,212-2. This decrease is abolished in the presence of a GABAA receptor (GABAAR) antagonist picrotoxin (PTX) suggesting a
regulatory mechanism in which CB1R activation decreases [DA]o via suppression of GABA release in the NAc core. Interestingly,
pulse-train evoked [DA]o increased with blockade of CB1Rs by an inverse agonist AM251. This result suggests DA release-suppressing
endocannabinoids are generated with our stimulation protocol.
COMPARATIVE ANALYSIS OF THE WANDERER GENES BETWEEN THE D. MELANOGASTER
AND D. VIRILIS DOT CHROMOSOMES
Jeannette Wong
Mentor: Sarah Elgin
The fourth, or “dot,” chromosome of Drosophila melanogaster exhibits an amalgam of chromatin properties: it has a gene density similar to
other euchromatic regions but has the typically high levels of association with heterochromatin protein 1 (HP1) seen in heterochromatic
regions. However, the dot chromosome of Drosophila virilis appears to be more euchromatic based on its lower levels of association with HP1.
Finishing and annotating the D. virilis dot chromosome has allowed comparison of DNA sequence properties (e.g. repeat density, gene size,
codon bias) between the two species. By these measures, the D. virilis dot is most like the D. melanogaster dot, and does not resemble euchromatin.
28
Comparative analysis between the D. melanogaster and D. virilis dot chromosomes reveals a small subset of “wanderer” genes that have migrated
on or off the dot. Analysis shows that the wanderer genes exhibit euchromatic characteristics when in non-dot locations, but have adopted
dot chromosome gene characteristics (greater length, low codon bias) when on the dot. These features may simply reflect the different
chromatin environments, or may contribute to the ability of the gene to be expressed in a domain that otherwise appears heterochromatic.
EFFECT OF INHIBITION OF HEDGEHOG PATHWAY ON BONE METASTASIS OF BREAST CANCER
Ceren Yalaz
Mentor: Katherine Weilbaecher
Cellular signal transduction components involved in embryonic and postnatal development may function as oncogenes, which cause cancer.
The Hedgehog (Hh) gene that plays crucial roles in cell proliferation, differentiation, pattern formation and maintenance is one of them.
The topic of this research was how the Hedgehog inhibitors decreased breast cancer growth and bone metastasis through direct anti-tumor
effects as well as indirect effects on the tumor microenvironment. Mice with osteoclasts with blocked Hh pathways were grown to analyze
the bone-tumor signaling in comparison to normal mice. The osteoclasts were observed in vitro for the production of osteoblast and
osteoclast growth signals. Also, mice were imaged for tumor growth and metastasis. It has not been observed that the Hh mediated
orthoclase signaling had no direct effect on tumor growth. Future direction of the research includes working on tumor/metastatic
microenvironment to understand the impact of cellular microenvironment on metastasis.
IDENTIFYING 1360-DEPENDENT HSP70-WHITE¬ REPORTER SITES IN THE
DROSOPHILA MELANOGASTER GENOME
Hao Yang
Mentor: Sarah Elgin
Heterochromatin, the condensed regions of a genome, plays a critical role in regulating gene expression. Position Effect Variegation (PEV)
is a phenomenon where partial silencing is observed when a euchromatic gene is juxtaposed to heterochromatin. PEV of the hsp70-white
reporter in Drosophila melanogaster is correlated with its distance to a DNA transposable element, 1360. This suggests the presence of a
sequence element in 1360 that is responsible for such dependence. A useful tool to test for such sequences is phiC31-mediated site-specific
recombination, wherein candidate 1360 sequence features can be tested at any PEV site dependent on 1360. To develop this tool, a
P-element mobilization of frt-1360-frt-hsp70-white flanked by phage attachment sites has been carried out. The desired sites were identified
by screening for male flies exhibiting PEV. DNA insertion sites were mapped by inverse PCR. The effect of 1360 on the reporter was tested
in PEV lines with pigment assays of sans 1360 versus 1360 containing flies. Forty-three lines of PEV flies were recovered from the screen.
Results from the pigment assays indicate that multiple lines displaying dependence on 1360 for gene silencing have been recovered, setting
the ground for testing various candidate 1360 features at these sites.
ARTIST STATEMENT: HAPPINESS EQUATION
Bo Zhang
Mentor: John Sarra
A painting is a conversation between the artist and the viewer. This series is composed of various conversations between me and the viewer
about happiness. I believe the way to evoke happiness in viewers is by capturing and sharing my understanding and experiences of happiness.
The conversation starts with visual stories. If I communicated successfully, the images would evoke emotions of happiness in the viewer and
enable them to empathize with the emotions I wish to express. Everyone’s definition and experiences with happiness differs. But no matter
how different our experiences and backgrounds, we can still find commonalities between each of us. I do not dare suspect that my paintings
can speak to anyone and everyone, but I hope that all of us can share something similar in our experiences of happiness. I believe that
happiness is something simple and fundamental that connects us all in some delicate way.
Accompanying every painting is a short story. The stories are just as important a part of the piece as any brushstroke. They help create
the context and background surrounding the painting that will better allow the viewer to relate to the image presented. The title of the piece
is the bold word embedded in the story. The title acts only as a formality and a way of distinguishing the pieces. The focus is on the entire
scene and the feeling presented by the story and image. No label could effectively represent and capture the entirety of the meaning in a piece.
The paintings depict my experiences. In the visual conversation with the viewer, I hope the viewer not only empathizes with the stories,
but will also recall joyful experiences of their own. In the paintings, I tell specific stories in my life. The viewers learn a little about who I am
through my paintings and I hope this occurrence stimulates a small sense of happiness for the viewers as if they created a new friendship.
The brushstrokes give a sense of movement that emphasizes the fleetingness of any moment. The actual occurrence or the variable details of
the setting are unimportant. The importance is in the sharing of the moment by those involved, and now the viewer.
29
SUMMER UNDERGRADUATE RESEARCH FELLOWSHIP (SURF) PRESENTATIONS
Presenters are listed alphabetically by last name.
CHAPERONE MUTANT DELETION SCREEN FOR ALTERED P-BODY DYNAMICS
Haejun C. Ahn1, Adeline Lin2, Heather L. True2, Department of Biology, Washington University, St. Louis, MO1; Department of Cell
Biology and Physiology, Washington University School of Medicine, St. Louis, MO2.
In a rapid response to environmental stress, cellular translation is drastically reduced to conserve energy. The translating pool of mRNAs is
sequestered into distinct locations called processing bodies (P-bodies) and can rejoin translating pool when the stress is removed. P-bodies
are ribonucleoprotein complex composed of aggregated core of proteins that bind to the non-translating mRNA. P-bodies in yeast consist
of eight different protein components, most of which play a role in mRNA degradation by acting as a 5’-decapping enzyme or as a
3’-exonuclease. While the various functions of P-body components have been investigated, the mechanism of how these P-body components
aggregate and disaggregate remains largely unknown.
We and others have observed that P-bodies in yeast assemble and disassemble at a remarkably rapid rate, within minutes of being
reintroduced to stress-free conditions, suggesting the participation of external factors such as chaperones which could assist the formation
and dissolution of these aggregation-prone proteins. We hypothesized that the loss of certain chaperones could adversely affect P-body
dynamics. To investigate this, we are conducting a screen to identify chaperone deletion mutants that have altered P-body dynamics.
HOW ELEVATION AND ASPECT AFFECT PLANTS STRESS
Lauren E. Barry1, Ellen I. Damschen1, Susan Harrison2, Department of Biology, Washington University, St. Louis, MO1; Department of
Environmental Science and Policy, University of California, Davis2.
Climatic extremes may lead to counterintuitive effects for species and communities. During a record-breaking heat spell in July 2008, we
measured wilting, mortality, and subsequent seed set for five upper-montane perennial herbs in the Klamath-Siskiyou Mountains, Oregon,
USA. We asked how these measures of plant performance varied with elevation (1500-2000m) and aspect (a warm west slope and a cool
north slope of the same mountain).
The proportion of wilted plants increased with elevation on the warm west slope, but showed no relationship with elevation on the cool
north slope. Wilted plants were more likely to die over the course of the growing season and this was especially true on the west slope. In
addition, a greater proportion of wilted plants on the west slope set seed than did unwilted plants on the west slope or any plant on the north
slope. These results suggest that plants at higher elevations are experiencing elevated stress, which is manifested in wilting and higher seed set
(severely stressed plants may allocate a greater proportion of resources to reproduction, increasing seed set). Interactions between elevation
and aspect may lead to counterintuitive climate effects.
GENETIC SCREEN TO IDENTIFY REGULATORS OF SYNAPSE FORMATION
Dominic Berns1, Sarah Naylor2, Aaron DiAntonio2, Department of Biology, Washington University, St. Louis, MO1; Department of
Developmental Biology, Washington University School of Medicine, St. Louis, MO2.
The chemical synapse is a highly specialized structure dedicated to the process of intercellular communication, the fundamental basis of
nervous system function. All higher order functions of the nervous system depend on precise synaptic contacts between appropriate cells.
Understanding the process of synapse formation is therefore essential to understanding neural function in general. At the Drosophila
melanogaster neuromuscular junction (NMJ), motor neurons synapse onto muscle cells in a highly stereotyped pattern, indicating a high
degree of genetic control.
In order to identify gene products required for normal NMJ development, we performed an anatomical screen on a library of piggyBac
insertion elements. Due to the consistent size, shape, and location of individual neuromuscular junctions, insertions affecting NMJ
development are easily identified. NMJ structure was visualized using antibodies to the presynaptic active zone protein Bruchpilot, and the
postsynaptic glutamate receptor subunit DGluRIII. From this screen, we identified a mutant, 140-245, which exhibits several morphological
defects at the NMJ. 140-245 exhibits a 40% decrease in bouton number, a 22% increase in terminal boutons, and a striking bouton spacing
defect. When quantified using the postsynaptic marker DLG, this spacing phenotype is manifested as a 2.75-fold increase in discontinuous
DLG foci. 140-245 does not appear to exhibit a functional transmission defect, as indicated by electrophysiological measures. The insertion
in question is located in the 3’ UTR of a type IV collagen gene, Dcg1. This collagen forms an essential component of basement membranes,
which surround nerve and muscle cells, and are present at NMJs. A causal link between Dcg1 disruption and the observed phenotype has yet
30
to be established, due to lethality of deficiency trans-heterozygotes. In order to conclusively demonstrate the Dcg1 dependence of the phenotype,
transgenic rescue with wild-type Dcg1 is underway. Pending the outcome of this experiment, further studies of the role of Dcg1 in NMJ formation
will be initiated. Future analysis of 140-245 could lead to a more complete understanding of pathways leading to proper synapse formation.
SYNTHESIS OF NEAR INFRARED DYE LABELED SOMATOSTATIN AGONIST/ANTAGONIST DENDRIMERIC
CONJUGATES USING CLICK CHEMISTRY METHODS
Adithya Bhat1, Mingfeng Bai2, Jinda Fan2, Kexian Liang2, Samuel Achilefu2, Biology Department, Washington University, St. Louis,
MO1; Radiology Department, Washington University School of Medicine, St. Louis, MO2
The somatostatin receptor family (SSTR) consists of five widely distributed G-protein coupled receptors that play key roles in regulating
intracellular signaling and cascade pathways. Poly(amidoamine) (PAMAM) dendrimers are a family of synthetic, highly branched polymers
that have been used as vehicles for targeted delivery of a variety of molecules. PAMAM dendrimers are based on an ethylenediamine core
possessing branched units built from methyl acrylate and ethylenediamine. Synergistic multivalent interactions produced by the polyvalency
of dendrimeric compounds amplifies desired receptor binding and molecular recognition. The goals of this project were to conjugate a
polyvalent PAMAM dendrimer to a somatastatin receptor agonist and antagonist attached to a near-infrared (NIR) dye, for visualization of
receptor binding, using click chemistry methods.
Click chemistry employs high fidelity reactions involving 1,3 dipolar azide-alkyne cycloaddition reactions in the presence of a catalyst.
Although a variety of fluorescent dyes are available, we chose to label our peptides with HL800 because of its excellent properties for in vivo
imaging, including solubility in aqueous medium, near infrared fluorescence emission, and low cytotoxicity. The presence of many
agonist/antagonist moieties on the polyvalent payload is expected to confer improved receptor binding affinity on the new molecular probe.
ANTI-INFLAMMATORY EFFECTS OF ADIPONECTIN ON EXPERIMENTAL AUTOIMMUNE
ENCEPHALOMYELITIS
Rani Bhatia1, Laura Piccio2, Anne Cross2, Neurology Department, Washington University School of Medicine, St Louis, MO2.
Multiple Sclerosis (MS) is thought to be an autoimmune disease in which the immune system attacks myelin sheaths in the Central Nervous
System (CNS) resulting in inflammation, demyelination and axon damage. The most commonly used animal model of MS is experimental
autoimmune encephalomyelitis (EAE), which can be induced in mice by immunization with protein components of CNS myelin. Dr. Cross
and her colleagues have recently shown that chronic Calorie Restriction (CR) inhibits the severity of EAE in mice (Piccio et al, JLB 2008),
and they are now examining by what mechanisms this occurs. CR has been shown to be associated with complex metabolic, hormonal and
immune/cytokine changes leading to reduction of inflammation and neuro-protection, which can both be beneficial in EAE. These effects
may take place because fat cells are known to secrete modulators of the immune system, also known as adipokines. With CR, secretion of
some of these (e.g. leptin known to be pro-inflammatory effects) are decreased, whereas other adipokines (e.g. adiponectin known to be antiinflammatory) are increased. Thus, the aim of this study is to focus on the role of adiponectin in modulating the autoimmune response in
mouse EAE, and eventually its role in the beneficial effects of CR on EAE.
The experiment involved examining clinical, histologic, and immune differences between adiponectin knock-out (Ad-/-) mice and
C57BL/6 (wild-type counterparts) during EAE. The mice were immunized subcutaneously with an emulsion containing a peptide derived
from a CNS myelin protein, myelin oligodendrocyte glycoprotein (MOG) 33-35. Ten to fifteen days post-immunization (pi) mice started
to develop neurological deficits. They were followed clinically for 25 days and scored daily based on a scale from 0 (no neurological signs) to
5 (death of the mouse). As expected, Ad-/- mice developed a more severe disease compared to C57BL/6 wild-type mice, which indicates a
significant role of adiponectin in down-regulating inflammation during EAE. At day 25 pi the mice were perfused and the CNS was removed
and sectioned for histology. The sections were stained to detect cellular inflammation, myelin loss, and axon loss. Also, the lymphoid organs
(spleen, lymph nodes) were removed and single cell preparations were made to assay for lymphocyte proliferation in response to the immunizing
antigen (MOG). The results showed no difference in the proliferation of splenocytes stimulated in vitro, meaning both groups had been
exposed to the MOG antigen and produced an immune response.
DEVELOPMENTS OF AN IMAGE GUIDED MICRO IRRADIATOR WITH RESPIRATOR GATING FOR HIGH
RESOLUTION LUNG TUMOR IRRADIATION
1
1
Jordan Birch , Charles Yu , Bethany Kassebaum2, Daniel Low2, and Enrique W. Izaguirre2. Biology Department, Washington University,
St. Louis, MO1; Radiation Oncology Department, Washington University School of Medicine, St. Louis, MO2.
Respiratory gating is a powerful technique used to help acquire high resolution anatomical data of the thoracic and abdominopelvic cavity
organs in preclinical radiotherapy. Gated microCT can successfully eliminate residual imaging artifacts that usually originate from the respiratory
31
motion of the lungs. These motions reduce the microCT image resolution and increase the probability of healthy tissue complications.
Radiobiological tumor models require sub millimeter tomographic images of the treatment area to provide accurate position of target tumors.
At the thoraxic cavity this is accomplished by using high resolution low dose respiratory gated microCT imaging. In the developed instrument,
the image gating is attained using a novel hot wire anemometer subsystem intergraded with the isoflurane anesthesia delivery unit which
records the breathing flow of the subject during image acquisition. The acquisition of scanned images is triggered using a phase detection
circuit to limit the set of projections to a particular phase of the respiratory cycle. The reconstructed microCT anatomical data is then used
to formulate highly conformal treatment plans to provide accurate beam delivery to lung tumors and to reduce unnecessary irradiation to
healthy tissues.
DOWNREGULATION OF MTOR PATHWAY IMPLICATED IN ENHANCED PERIPHERAL
AXONAL OUTGROWTH FOLLOWING INJURY
Steven Borson1, Namiko Abe2, Valeria Cavalli2, Biology Department, Washington University, St. Louis, MO1; Anatomy and
Neurobiology Department, Washington University School of Medicine, St. Louis, MO2.
The peripheral and central nervous systems have clear differences with respect to ability to regenerate. Neurons in the CNS degenerate after
injury, while those in the PNS have a remarkable ability to regenerate their axons and reinnervate their targets. The main goal of this work
is to determine the molecular differences between the two neuronal types that give rise to the differences in their ability to regenerate. One
pathway that is implicated in regulating the intrinsic ability of neurons to regenerate is the mTOR signaling pathway, which regulates cell
growth, survival, motility and translation. Work from Zhigang He’s group has shown that CNS neurons downregulate the mTOR pathway
following injury, and that this downregulation is correlated with decreased regenerative ability.
We find that in contrast, dorsal root ganglia (DRG), which are sensory neurons in the PNS, upregulate the mTOR pathway following
injury. To determine whether mTOR activity is sufficient to increase axonal growth capacity after injury, we took a genetic approach to
constitutively upregulate the pathway in sensory neurons. We created a conditional knockout mouse in which the TSC2 gene, an inhibitor
of the mTOR pathway, is deleted in all sensory neurons. Our preliminary results show that DRGs dissected from TSC2 conditional knockout
mice have enhanced axonal outgrowth in vitro, consistent with the role of the mTOR pathway in regulating axonal growth after injury. We
are currently working to determine whether the TSC2 conditional knockout mice show enhanced regeneration in vivo.
ROLE OF EXTRAHYPOTHALAMIC CORTICOTROPIN-RELEASING HORMONE (CRH)
IN NOCICEPTION USING A TRANSGENIC MOUSE MODEL
Bowling RE1, Gereau RW2, Kolber BJ2. Department of Anesthesiology, Washington University School of Medicine, Washington
University Pain Center, St. Louis, MO2.
Chronic pain is a prevalent and debilitating condition whose pathology is incompletely understood and which is not fully treatable. We
sought to investigate how chronic pain is modulated by the neuropeptide corticotropin-releasing hormone (CRH) when it is expressed both
early in life and outside the hypothalamic-pituitary adrenal (HPA) axis, the mediator of the body’s endocrine response to this form of severe
stress. Previous studies have indicated a dose-dependent effect of CRH on pain sensitivity. Furthermore, early-life stress has been shown to
alter pain sensitivity in adult animals. In this study, transgenic male mice using the “tetracycline-off ” system provided an experimental model
of forebrain inducible overexpression of CRH (FBCRHOE) without the confounding effects of external stress. Mice overexpressed CRH
until postnatal day 21. Nociceptive behaviors were tested at 6-8 weeks under baseline conditions and following peripheral inflammation with
the von Frey and Hargreaves sensory paradigms. No significant effect between genotypes (as measured by paw withdrawal latency) was found
for either the baseline or formalin von Frey mechanical sensitivity tests. However, a significant difference in thermal sensitivity was observed
between control and FBCRHOE mice in the baseline Hargreaves test, with the overexpressors exhibiting thermal hyposensitivity. These results
indicate that early exposure to higher levels of extrahypothalamic CRH may have an inhibitory effect on thermal nociception later in life.
ESTABLISHING THE RELATIONSHIP BETWEEN CYANOGENESIS AND HERBIVORE PREFERENCE
IN SEEDLING TRIFOLIUM REPENS
Graham Caulkins1, Dr. Kenneth Olsen1, Nicholas Kooyers1, Biology Department, Washington University, St. Louis, MO1.
Cyanogenesis, the ability for a plant to release cyanide after tissue damage, has been studied as a textbook example of adaptive polymorphism
in white clover (Trifolium repens). The biochemistry and genetics underlying this polymorphism are well characterized; two unlinked genes,
Ac and Li, control the ability to produce cyanide. However, there are still underlying ecological questions about the selective factors that
maintain the polymorphism. While previous studies have suggested that cyanogenic phenotypes deter small herbivores, few studies have been
conducted under controlled experimental conditions; in addition, few studies have examined herbivory at the seedling life stage, when
32
protection from herbivores would be most critical for plant survival. In this study, we examine the effect of mollusk herbivory on cyanogenesis
phenotype fitness in controlled greenhouse experiments using white clover seedlings. We advance previous knowledge by using both seedlings
from native European populations as well as non-native populations collected near Saint Louis.
We have determined that the garden slug (Arion distinctus), a widespread predator of white clover, significantly prefers acyanogenic
seedlings in choice experiments using European populations. However, the European sample set does not represent all possible Ac and Li
genotype combinations and could potentially be reflecting confounding effects of geographical origin. Analyses of the Saint Louis population
data are presently in progress. Preliminary results indicate no statistically significant difference in mollusk herbivory with respect to
cyanogenesis phenotype. This finding potentially indicates that some factor other than herbivore deterrence may determine cyanogenesis
frequencies in non-native clover populations. These results do not match expectations from past studies and prompt further investigation.
PORTABLE NEURAL CONTROL SYSTEM:
ANALOG COMPONENT DEVELOPMENT
Samir Chabra2, Scott Burns2, Dennis Barbour2, Biomedical Engineering Department, Washington University, St. Louis, MO2.
Neuroplasticity describes the ability of the brain to create novel connections between its neurons. These new connections form according to
Hebbian theory, which states that, “neurons that fire together wire together”. This process enables learning to take place. The Portable Neural
Control System (PNCS) is a device that is made up of a recording and stimulating system of electrodes, which can induce plasticity in the
brain through targeted stimulation of neurons. The PNCS detects neural signals, triggering the device to stimulate a specific area of the brain.
This system must be battery powered for about 24 hours. As a result, the circuit design must consume very small amounts of power and still
generate currents large enough to stimulate the brain.
My contribution to the PNCS design involved the design of the front-end input amplifier, the stimulating current source, and preliminary
power supply design. The front-end of the recording side of the PNCS is an active band-pass amplifier. Each amplifier amplifies the neural
signal of a single implanted electrode while filtering out signals with frequencies below 400 Hz and above 4 kHz. Filtering the signal reduces
the noise in the signal that reaches the processor of the unit, and improves action potential detection. The preliminary design for the filter
section was accomplished using Texas Instruments FilterProTM software. After design, the filter was tested by passing signals through it and
recording them on a computer.
The stimulating amplifier in the PNCS converts a voltage output from the processor to a constant stimulating current in the implanted
electrodes. This amplifier consists of a Howland current source, employing a balanced set of resistors around an OpAmp to create a constant
current. Using this type of current source helps keep the part count low because several of these OpAmps can be combined on a single
microchip. The current source must be bi-phasic, meaning it produces positive and negative currents, in order to prevent ion buildup around
the implanted electrode. This means that positive and negative power supply voltages must be available to the OpAmp, relative to the ground
potential of the animal.
The power supply design is made up of voltage regulators that produce a steady 3 volt primary voltage rail, and a steady 1.5 volt secondary
voltage rail from a single 3.3 volt battery. After considering the electrodes that would be used for the PNCS, the power supply required a
voltage booster to provide the necessary positive and negative 20 volt supply voltages for the stimulating amplifier. The power supply was
not robust enough to supply constant voltages while producing stimulating currents once the voltage booster was added. As a result, the
power supply must be redesigned.
IMPROVED PHOTOSYNTHETIC PRODUCTIVITY FOR RHODOBACTR SPHAEROIDES
VIA SYNTHETIC REGULATION OF THE LIGHT HARVESTING ANTENNA LH2
Stephanie Chang1, Jaffre Athman1, Jacob Cecil1, Brendan Cummings2, Colin Foley1, Jeff Knudsen3, Alice Meng2, Jacob Rubens1, Thomas
Stevens2, Christine Kirmaier4, Yinjie Tang3, Robert Blankenship1,4, Biology Department, Washington University, St. Louis, MO1;
Department of Biomedical Engineering, Washington University St. Louis, MO2; Department of Energy, Environmental & Chemical
Engineering, Washington University, St. Louis, MO3; Department of Chemistry, Washington University, St. Louis, MO4.
Photosynthetic light harvesting antennas function to collect light and transfer energy to a reaction center for photochemistry. Phototrophs
evolved large antennas to compete for photons in natural environments where light is scarce. Consequently, cells at the surface of
photobioreactors over-absorb light, leading to attenuated photobioreactor light penetration and starving cells on the interior of photons. This
reduction of photosynthetic productivity has been identified as the primary impediment to improving photobioreactor efficiency. While
reduction of antenna size improves photosynthetic productivity, current approaches to this end uniformly truncate antennas and are difficult
to manipulate from the perspective of bioengineering. We aim to create a modifiable system to optimize antenna size throughout the bioreactor
by utilizing a synthetic regulatory mechanism that correlates expression of the pucB/A LH2 antenna genes with incident light intensity. This
new application of synthetic biology serves to transform the science of antenna reduction into the engineering of antenna optimization.
33
HORMONAL CROSSTALK IN TRANSCRIPTIONAL REGULATION OF GLUT1:
MAPPING THE PROMOTER REGION OF MOUSE GLUCOSE TRANSPORTER 1.
Tiffany Chi1, Antonina Frolova2, Kelle H. Moley2, Ob/Gyn Department, Washington University School of Medicine, St. Louis, MO2.
Facilitative glucose transporter 1 (GLUT1) is the major glucose transporter responsible for glucose uptake in mouse endometrial stroma, the
uterine lining where a developing embryo implants. The hormones estrogen (E2) and progesterone (P4) are partially responsible for the regulation
of glucose metabolism in endometrial stromal cells (ESCs) through the opposing modulation of GLUT1 expression. Previous studies have
shown that P4 upregulates GLUT1 expression, whereas E2 reverses the effect. As a result, an imbalance between estrogen and progesterone
levels around the time of embryo implantation may interfere with glucose utilization in the endometrial stroma, leading to endometrial
dysfunction and subsequent failed pregnancy.
Mapping the regulatory sites on the putative GLUT1 promoter is the first step in investigating the mechanism of crosstalk between E2
and P4. We identified the putative sites of P4 and E2 response elements. Next, luciferase-reporter deletion constructs of the promoter were
created in order to isolate the putative response elements and used to investigate promoter activity in relation to the two hormones in
question. In response to either E2 or P4, promoter activity decreased sequentially with regions -3021 bp, -1910 bp, and -1245 bp upstream
of the transcription start site for GLUT1. These results are consistent with the locations of the putative binding sites. However, E2-related
promoter activity diverges from that of P4 with -957 bp and -271 bp upstream regions. With E2, activity increased significantly after the deletion
of the -1245 bp to -957 bp region, suggesting the region may contain a repressor binding site. Due to relatively low levels of promoter
activity of the first 3 kb upstream of the transcription start site, it is possible that this limited region is insufficient to drive GLUT1
transcription and subsequent protein expression. Notably, the first two introns of the GLUT1 gene are several kb long and may contain other
important regulatory sites. The initial analysis of the 3 kb upstream region marks the first step toward characterizing the GLUT1 promoter
and the transcriptional crosstalk mechanism between estrogen and progesterone.
CIRCADIAN RHYTHM OF CYCLIC AMP, CELL CYCLE REGULATORS, AND CLOCK GENES
Eun-joo Anna Choe1, Luciano Marpegan1, Erin Gribben2, Mark Woerner2, Nicole Warrington2, Joshua Rubin2, Erik Herzog1,
Biology Department, Washington University, St. Louis, MO1; Department of Pediatrics, Division of Oncology. Washington University
School of Medicine St. Louis, MO2.
Astrocytoma is the most common type of brain tumor but in past fifty years, there has been a little improvement in its treatment. Currently
there is a hope that an improved understanding of why these tumors form will support the development of better therapies. Recent studies
have shown that disruption of circadian rhythm increases the risk of cancer and that circadian rhythm exists within a cell cycle. We sought
to investigate whether disruption of circadian rhythm plays a role in the transformation of astrocytes into astrocytomas. Using cells derived
from a human glioblastoma, a highly malignant form of astrocytoma, we demonstrated that cell cycle regulators including pRb780, pRb795,
pRb807/811, CylinD1, CyclinD3, and p21 exhibit diurnal variation in expression that corresponds to diurnal variation in cAMP levels. As
cAMP is known to regulate both clock gene expression and cancer cell growth these data suggest that a more comprehensive understanding of
the relationship between circadian rhythm, cell cycle, and cAMP levels could lead to a more effective time-specific treatment of astrocytomas.
A COMPARISON OF HISTORIC AND CONTEMPORARY PLANT-POLLINATOR
INTERACTIONS OF INVASIVE SPECIES
Yan Yi Anny Chung1, Laura Burkle1, Tiffany Knight1, Biology Department, Washington University in St. Louis, MO1.
Animal pollination is a critical ecosystem service required by over 90% of flowering plants. Like other interspecies interactions, this service
is being disrupted by the introduction of invasive alien species. Recent studies are mostly focused on single species of plants or pollinators,
and research at the community level is necessary for a complete understanding of the pollination ecology of alien plants. In the late 1800’s,
entomologist Charles Robertson documented all the plant-pollinator interactions in Carlinville, Illinois. His dataset consists of over 15,000
unique interactions, and provides an unprecedented opportunity to revisit the area and compare current interactions with historical ones.
In this study we re-sampled a subset of the plant-pollinator interactions in Carlinville; focusing on old (species from Robertson’s dataset)
and new (species that have invaded since Robertson’s time) alien species. We examined how pollinator interaction patterns of old alien plant
species have changed over time, and if different pollination patterns could be explained by phylogenetic novelty, breeding systems, or floral
morphology. We found no significant differences between the number of links to pollinators of old and new alien plants, which suggests that
the present pollinator community or habitat may be more conducive to alien species than it was historically.
34
SPATIAL AND TEMPORTAL VARIATION OF SEED PREDATION IN
THE MATRIX OF A CORRIDOR SYSTEM
Michael Craig1, Lars Brudvig1, John Orrock1, Biology Department, Washington University, St. Louis, MO1.
Corridors have been demonstrated to be an important conservation tool in addressing habitat fragmentation and loss, the gravest threats to
biodiversity worldwide. By improving connectivity between patches, corridors increase the diversity of plant communities. Furthermore,
recent work suggests that the effect of corridors can extend beyond connected patches, as adjacent habitats also have greater diversity. This
“spillover effect” could occur because either more seeds arrive in these areas, or fewer seeds are removed by seed predators. However, no studies
have documented which of these mechanisms contributes to this increased diversity. I investigated seed predation by counting the number
of remaining seeds in seed trays placed in the matrix of a landscape-level, highly replicated corridor system. Initial results for Phytolacca americana
indicate patch type only has a significant effect on rates of seed predation at 15 m from the edge (p = .0063). At this distance, the average
proportion of seeds removed in connected patches more than doubled removal in winged or rectangular patches. These results suggest that
connectivity increases seed predation in the matrix surrounding connected patches, although not across all distances. Thus, lower seed
predation may not drive increased diversity in habitats adjacent to connected patches.
GENETIC MAPPING OF A HYPOXIA RESISTANT MUTATION IN C. ELEGANS
Bartosz Czernia, Michael C. Crowder, Ph.D., M.D.2, School of Engineering, Washington University, St. Louis, MO; Anesthesiology
Department, Washington University School of Medicine, St. Louis, MO2.
Hypoxic cell death is the cause of most heart attacks and strokes. However, there is no approved therapy for hypoxic injury. In order to identify
novel mechanisms for treatment of hypoxic injury, the Crowder lab performed a screen in the nematode C. elegans for mutations that
produce animals resistant to hypoxic death. To identify the gene mutated in one of the hypoxia resistant mutants – MC249, I mapped the
hypoxia resistant phenotype of MC249.
MC249 was crossed with a wild type strain from Hawaii – CB4856, which has a high density of single nucleotide polymorphisms (SNPs)
with an English wild type strain N2, which is the genetic background for MC249. Hypoxia resistant F2 progeny from the MC249 X CB4856
cross were genotyped for 48 SNPs spread among the six C. elegans chromosomes. SNP genotyping revealed a significant lack of CB4856
SNPs on the left arm of chromosome I.
Genotyping of additional hypoxia resistant animals from a MC249 X CB4856 cross confirmed mapping of the hypoxia resistant
phenotype to approximately -17 map units on the left arm of chromosome I. Future studies will refine mapping to a smaller genetic interval,
followed by definitive identification with transformation rescue and sequencing of the candidate gene.
DIFFERENTIAL EXPRESSION OF 15-LIPOXYGENASE ISOZYMES IN COPD
Geoffrey Dang-Vu1, Derek E. Byers2, John T. Battaile2, Anand Patel2, Yael Alevy2, Eugene Agapov2, Michael J. Holtzman2, Biology
Department, Washington University, St. Louis, MO1; Pulmonary Department, Washington University School of Medicine, St. Louis, MO2.
The levels of arachidonate 15-lipoxygenase (15-LO) are increased in the airways of patients with asthma and may contribute to immune cell
recruitment and associated airway pathology via the production of 15- and 12(S)-hydroxyeicosatetraenoic acids (HETEs). Similarly, expression
of 12-lipoxygenase (the mouse homolog) is increased in association with IL-13, arginase 1, and related markers of alternatively-activated
macro-phages in a mouse model of virus-induced chronic airway disease. Two isoforms of 15-lipoxygenase (15-LO-1 and 15-LO-2) with
40% sequence homology have been identified in humans. Although both forms appear to be expressed in airway epithelial cells, the relative
expression in chronic lung disease still needs to be defined.
Here, we examined the expression of 15-LO-1 and 15-LO-2 in lung samples from patients with COPD. We find that levels of 15-LO-1
and 15-LO-2 mRNA correlate significantly with IL-13 and MUC5AC mRNA levels in lung resection samples from patients with GOLD
0-4 COPD. In addition, we observed that immunostaining for 15-LO-1 is found predominantly in ciliated epithelial cells, whereas 15-LO-2
also localized to subepithelial PMNs and macrophages and vascular endothelial cells. Epithelial immunostaining for 15-LO-1 is more intense
in COPD than non-COPD subjects. Moreover, the levels of 15-LO-1, but not 15-LO-2 are markedly increased in cultured human airway
epithelial cells stimulated with IL-13, a cytokine that appears to drive the development of COPD. Together, our results indicate that 15-LO-1
and 15-LO-2 expression is increased in COPD, and the distinct pattern of expression for each of these isozymes implies separate roles in the
epithelial and immune cell events that contribute to the pathogenesis of COPD. These isozymes therefore represent potential biomarkers to
stratify patients with chronic inflammatory lung disease.
35
POPULATION STRUCTURE OF KEY HOST TRANSCRIPTION MODULATOR GENE IN TOXOPLASMA GONDII
Lisa Deng1, Asis Khan2, L. David Sibley2, Biology Department, Washington University, St. Louis, MO1; Molecular Microbiology
Department, Washington University School of Medicine, St Louis, MO2.
Toxoplasma gondii is a protozoan parasite that infects warm-blooded vertebrates, including about 25% of the world’s human population. The
infection can cause disease in individuals with a compromised immune system (1). The primary host is the cat family, where the parasite
undergoes sexual recombination. Transmission occurs when an infected cat sheds oocysts that are ingested by an intermediate host.
Organelles called rhoptries are important for parasite invasion because rhoptry proteins (ROPs) are secreted into the host following contact
(4). The population structure of T. gondii consists of eleven haplogroups, three of which make up almost all of the strains found in North
America and Europe. The South American strains bring much more diversity to the population (2). Two ROPS with major effects on virulence
in mice are ROP18 and ROP16, which are both serine-threonine kinases, meaning that they catalyze the phosphorylation of another protein
and change its function (5). ROP16 was identified after finding differences in host gene expression levels when infected with different strains
of T. gondii. The typeI/III strains’ ROP16 alters host transcription, causing sustained activation of STAT3/6, lowering levels of IL-12, and
suppressing the host immune system. Contrastingly, the typeII strain ROP16 only transiently phosphorylates STAT3/6, induces the host to
produce more IL-12, and thus activates the immune response (3). The aim of my research is to investigate how many alleles of ROP16 exist
and to determine how they are distributed in the population. Defining the genetic diversity of the ROP16 gene from 25 representative strains
of T. gondii will shed light on how this gene has impacted the population structure of T. gondii today.
THE EFFECTS OF COFILIN-1 MUTATIONS AND AN AIP1 DELETION ON YEAST ACTIN
PATCH MOVEMENT DURING ENDOCYTOSIS
Jarod DuVall1, Meng-Chi Lin2, John A. Cooper2, Brian J. Galleta2, Biology Department, Washington University, St. Louis, MO1;
Cell Biology and Physiology Department, Washington University School of Medicine, St. Louis, MO2.
Actin filaments are involved in a number of processes including endocytosis. Depolymerization of these filaments occurs rapidly so that the
actin monomers can be recycled in new filament structures. Coronin, cofilin, and actin-interacting protein 1 (Aip1) have been shown to be
independently important in actin depolymerization, and the three proteins work together to increase the turnover rate of actin monomers.
Cofilin depolymerizes actin filaments by preferentially severing older filaments, and Aipl caps barbed ends on severed actin filaments
preventing re-polymerization of the actin fragments. One study showed that “bursting,” very rapid depolymerization of actin filaments,
occurs when cofilin, coronin, and Aip1 are combined in vitro (1).
The Cooper lab has examined the importance these interactions in vivo by studying Cofilin 1 (Cof1), Coronin 1 (Crn1), and Aip1 in
cortical actin patches in budding yeast cells. The lifespan of actin patches, which are involved with endocytosis, can be broken down into
three phases. During phases I and II, the patches form and remain on the cell membrane, and in phase III, the patches pinch off from the
membrane and move into the cell. As part of the larger project, I studied the effects of three cofilin mutations (cof1-15, cof1-19, and
cof1-22) and an aip1 deletion on the time patches spent on the cell membrane.
Sla2 is an adapter protein that binds to the cell membrane and recruits molecules involved with endocytosis. Because Sla2 is found in actin
patches during phases I and II, a Sla2-GFP construct was used to label the patches while they remained on the membrane. A Cof1-RFP
construct was used to label the cofilin in the mutant and wild type cells. Real-time fluorescence movies of living cells were taken, and
computer tracking program was used to analyze the patch movement.
All three mutations and the deletion were found to increase the phase I and phase II lifespans. This is due to the mutations reducing the
actin monomer recycling in the cell. Additionally, the aip1 deletion was found to have a small effect on the cell suggesting that the
“bursting” from the combination of Aip1, cofilin, and coronin may not be physiologically significant.
MODELING AXON DEGENERATION IN D. MELANOGASTER
Sarah Y. Ebstein2, Martha R. C. Bhattacharya2, Aaron DiAntonio2, Department of Developmental Biology, Washington University
School of Medicine, St. Louis, MO2.
Axon degeneration is a process that occurs during many neurodegenerative diseases, however, its mechanism is still largely unknown. We
found that disruptions of CG7177, a homolog of the mammalian neurodegeneration gene Wnk1, lead to an axon degeneration phenotype.
The nerves swelled with the mutation, showing an approximately 50% increase in diameter compared to wild type. We are also using model
of drug induced axon degeneration through the chemotherapeutic agent taxol. We have done a screen for genes that protect the sensory
neurons when treated with the microtubule-stabilizing agent. In a wild type fly, taxol treated larvae show fragmented axons. We have found
genes that when knocked down or over expressed show both more intact axons and dendrites than in similarly treated controls. We believe
that the CG7177 data and the screen will help contextualize axon degeneration. Understanding the mechanisms that regulate degeneration
and protection of axons may inform treatment strategies for numerous diseases.
36
APOE ANTIBODY AS A MEANS FOR REDUCING AMYLOID PLAQUE DEPOSITION
Adam E. M. Eltorai1, Jungsu Kim2, David M. Holtzman2, Biology Department, Washington University, St. Louis, MO1;
Department of Neurology, Washington University School of Medicine, St. Louis, MO2.
Alzheimer’s disease (AD) is a neurodegenerative disease that impairs cognition and causes behavioral changes in the elderly. More than 60%
of dementia in individuals 65 years or older is caused by AD. Aβ in the brain is hypothesized to drive AD pathogenesis.
Although there are currently no known disease-modifying treatments for AD, a number of approaches are being tested, such as interfering
with the enzymes responsible for the production of Aβ, decreasing amyloid plaques, and immunotherapy to reduce levels of Aβ in the brain.
Recent immunotherapy studies in transgenic mouse models of AD have utilized a passive immunization approach, injecting antibodies to
Aβ, instead of requiring the animal to mount its own immune response to Aβ. These passive immunotherapy treatments have shown to be
effective in clearing plaques in transgenic mice. In our study, we have taken a novel approach to passive immunization by using antibodies
against Apolipoprotein E (ApoE). ApoE is known to interact with Aβ and enhance the aggregation propensity of Aβ. The goal of this project
is to use the ApoE antibodies to prevent the detrimental effect of ApoE and to trigger a beneficial microglia response, consequently reducing
Aβ plaque deposition in the brain. Our preliminary data show that mice treated with the ApoE antibody have a reduced plaque load compared
to a properly matched negative control. Such findings may help further elucidate the precise function of ApoE in AD pathogenesis. Moreover,
the reduction in Aβ plaque levels in the brain in response to the ApoE antibody has potentially significant implications for new AD research
directions (i.e. testing of other Aβ-associated molecules could serve as a platform for AD prevention or therapy).
INTRACELLULAR METABOTROPIC GLUTAMATE RECEPTOR 5 (MGLUR5) INDUCES FRAGILE X MENTAL
RETARDATION PROTEIN (FMRP) LEVELS IN STRIATAL AND HIPPOCAMPAL NEURONS
Paul G. Fahey1, Vikas Kumar2, Karen L. O’Malley2, Biology Department, Washington University, St. Louis, MO1; Anatomy and
Neurobiology Department, Washinton University School of Medicine, St. Louis, MO2.
Fragile X Syndrome (FXS), the most common form of inherited mental retardation, is caused by a deficiency of Fragile X Mental Retardation
Protein (FMRP). FMRP is known to oppose functions of G-protein coupled Metabotropic Glutamate Receptor 5 (mGluR5). In FXS, due
to absence of FMRP, there is exaggerated mGluR5 signaling. Studies in mouse models of FXS have shown that blocking mGluR5 either
genetically or pharmacologically has protective effects. Thus mGluR5 is an important therapeutic target for FXS. One of the intriguing properties
of mGluR5 is that functional mGluR5 is localized intracellularly as well as on the cell membrane, and thus far the role of intracellular
mGluR5 with regards to FMRP has been overlooked. Selective activation of intracellular mGluR5 by combination of impermeable mGluR5antagonist LY393053 and the transported agonist quisqualate (Quis) leads to upregulation of activity regulated cytoskeletal protein (Arc/Arg
3.1) in striatal neurons. Arc/Arg3.1 is an immediate early gene and a substrate for FMRP and its activation by intracellular mGluR5
indicates involvement of these receptors in FXS. Using immunocytochemistry and western blots, it was found that selective intracellular
mGluR5 activation results in FMRP upregulation in striatal cultures. Since most of the studies pertaining to FXS have been conducted in
hippocampal neurons, we tested if intracellular mGluR5 exerts its effects in these neurons as well. Our results indicate that intracellular
mGluR5 like cell surface counterparts led to ~ 2 fold increase in FMRP levels in hippocampal neurons. Additionally, changes in dendritic
morphology were observed that resembled the dendritic phenotypes observed in FXS patients. Taken together, our findings point towards a
novel mode of FMRP regulation mediated by intracellular mGluR5.
SYNTHESIS OF BIFUNCTIONAL COMPOUNDS FOR STUDYING THE INTERACTIONS OF METAL IONS
WITH AMYLOID β PEPTIDES IN ALZHEIMER’S DISEASE
Darren Finkelstein, Liviu Mirica, Chemistry Department, Washington University, St. Louis, MO.
Alzheimer’s disease is one of the leading causes of death in the United States. The disease can be described by amyloid plaques formed by the
aggregation of amyloid β (Aβ) peptides in the brain leading to neuron degeneration. It has been suggested from numerous studies that Aβ
plaques bind tightly to transition metals ions such as copper, iron, and zinc. These transition metals are hypothesized to act as catalysts for
the formation of protein aggregates.
A main goal of our research is to synthesize specific types of compounds that will act as ligands and bind to the metal ions and Aβ
peptides. These “bifunctional” compounds are characterized by their ability to ligate the metals. By binding to the metals, the bifunctional
compounds inhibit the interaction between metal ions and amyloid plaque formation and thereby are proposed to slow down neuron
degeneration. The two step synthesis includes formation of a phenyl benzothiazole backbone followed by addition of a metal-binding amine
fragment via a Mannich reaction.
The bifunctional compounds as well as their corresponding metal complexes can be characterized using UV-vis and fluorescence
spectroscopy. Spectroscopic information may reveal the ability of such compounds to be utilized as fluorescent sensors as well as potential
imaging agents of the amyloid aggregates in vivo.
37
DEVELOPMENTAL DNA ELIMINATION/RETENTION OF CONSERVED M ELEMENT-LIKE
SEQUENCES IN TETRAHYMENA THERMOPHILIA
Kevin Gao1, Douglas L. Chalker1, Biology Department, Washington University, St. Louis, MO1.
Tetrahymena thermophila is a ciliated protozoa, unconventional because it contains two nuclei, a silent but heritable micronucleus and a
transcriptionally active macronucleus. To specialize its somatic genome, Tetrahymena streamlines a germline (micronuclear)-derived developing
macronucleus by eliminating approximately 20kbs of micronucleus- limited DNA.
The segments of DNA removed are called Internal Eliminated Sequences (IES), which are recognized by a homology-dependent RNAi
“scanning” mechanism that marks sequences for elimination. The M element is a well characterized IES that has a conserved 200 bp internal
region. Although the M element is always excised during normal development into one of two alternative rearrangement products, many
macronuclear sequences that share the 200 bp conserved region (M-like sequences) are retained.
In this study, our data shows that M-like sequences can be deleted in a vector based assay, suggesting that genomic context is important
for determining the fate of internal eliminated sequences. The 200 base pair M like region is hypothesized to be important for the small RNA
recognition mechanism, and preliminary data suggests that M-like sequences without the 200bp M-like region cannot be recognized by the
excision machinery. The data conforms to the hypothesis that eukaryotes use epigenetic factors to eliminate or to retain sequences.
ENDOGENOUS ROLES FOR THE TRANSCRIPTION FACTOR HIF-1α AND ITS TARGET GENES
IN PROTECTION OF ISCHEMIC BRAIN ENDOTHELIUM
Robert Gilchrist1, Dr. Jeff Gidday2, Biology Department, Washington University, St. Louis, MO1; Neurology Department, Washington
University School of Medicine, St. Louis, MO2.
Prolonged hypoxia generally leads to cell death, but brief exposures to hypoxia (hypoxic preconditioning (HPC)) prompt adaptive cellular
responses that lead to “ischemic tolerance” (IT) to future ischemic insults in many tissues. I investigated the HPC-IT response of cultured
cerebral microvascular endothelial cells to elucidate the hypoxia-sensitive transcription factors of IT in these cells. Previous findings
suggested that 6 h of 1% O2 was an effective HPC stimulus for protection against fatal injury from 24 h of simulated ischemia started 16 h
later. This model proved difficult to reproduce, with LDH cytotoxicity analysis indicating an erratic and sometimes heightened ischemic
sensitivity in HPC-treated cells, as well as inconsistencies in overall cell death between trials without HPC. Manipulations were made to the
hypoxic chamber, oxygen concentrations, cell confluence, and cell death assay to achieve consistent HPC but proved ineffective.
Immunoblotting for known hypoxia-inducible gene products suggested the HPC protocol was sufficient to elicit appropriate expression profiles.
Future progress requires documenting reproducible HPC and injury in this model. Improvements may require a quantitative gauge of cell
plating density upon passage, cell confluence at experiment onset, and different assays for cell death.
EVOLUTIONARY DIVERGENCE OF THE BASIC HELIX LOOP HELIX PROTEIN, DIMMMED:
EXPRESSION, ACROSS SIXTEEN SPECIES OF DROSOPHILA
1
Nicole Gong , Dongkook Park2, Paul H. Taghert2, Department of Biology, Washington University, St. Louis, MO1; Department of
Anatomy and Neurobiology, Washington University School of Medicine, St. Louis, MO2.
Expression of the basic helix loop helix protein, DIMMED, identifies the professional secretory cell type in the nervous system of Drosophila.
The sequence for DIMMED is highly conserved across species of Drosophila, and the expression pattern of DIMM in the central nervous
system and periphery has only previously been studied in Drosophila melanogaster. To study the evolution of secretory systems, we have begun
to describe DIMMED expression in other species of Drosophila. We performed immunocytochemistry of the nervous systems of third instar,
using antibodies against DIMM, and against a conserved neuropeptide (dFMRFamide) then viewed specimens under a confocal microscope.
14 of the 16 species studied showed some varied levels of DIMM staining, but the majority of species showed inconsistent or faint staining.
Of these 14 species exhibiting some DIMM staining, D. erecta was the most consistent and reproducible. Therefore we intend to focus first
on a direct comparison between the number and positions of DIMM-positive neurons in the CNS of these two Drosophila species. To extend
the analysis further in evolution will require the generation of antisera that can detect DIMM sequence in more distantly related species.
38
MICRORNAS AS BEHAVIORAL MOLECULAR SWITCHES
Jacob K. Greenberg1, Yehuda Ben-Shahar1, Biology Department, Washington University, St. Louis, MO1.
Small, non-coding microRNAs (miRNA) are important regulators of gene expression. Studies have shown that through the inhibition of protein
translation, miRNAs are involved with regulating diverse processes from cancer cell regulation to neural growth. Importantly, miRNAs are
pleiotropic, affecting a large number of gene targets. We hypothesized that miRNAs are functioning as molecular switches involved with
behavioral plasticity. To study this question, we used the honeybee, Apis mellifera, as a model organism because of the stereotypic and well
characterized division of labor displayed by worker bees. Over the course of their lifetime, these bees assume a variety of distinct roles within
the colony, ranging from caring for brood to foraging for food outside the hive. In addition, previous work has shown that transitions in
behavioral roles are plastic and are associated with changes in expression levels of many mRNAs. After testing a subset of miRNAs, along
with mRNAs known to regulate miRNA production, we found that certain genes appear more highly expressed in certain behavioral groups
than in others. In addition, initial experiments indicate that within honeybees of a particular group, there are differences in expression levels
of certain miRNAs among different tissues. Finally, phylogenetic analysis shows that different miRNAs show different levels of conservation
across insect species. Ultimately, this evidence may support general understanding of the brain functions underlying behavioral plasticity.
THE EFFECT OF DIETARY VITAMIN A ON GUT DENDRITIC CELL HOMEOSTASIS
Elyse Hanly1, Caihong Wang2, Keely G. McDonald2, Leroy Wheeler2, Rodney D. Newberry2, Biology Department, Washington
University, St. Louis, MO1; Gastroenterology Department, Washington University School of Medicine, St. Louis, MO2.
Previous studies demonstrated a critical role for vitamin A metabolites produced by dendritic cells (DCs) in directing the homing of
lymphocytes to the gut, and for the production of secretory IgA. Decreased secretory IgA production is a well described consequence of
vitamin A deficiency, resulting in increased susceptibility to gastrointestinal infections. A direct effect of dietary vitamin A on intestinal DCs
has not been previously investigated. In this study we evaluated the direct relationship between dietary vitamin A intake and the presence of
intestinal DCs. We hypothesized that reduced dietary vitamin A directly affects intestinal DC populations by inhibiting cell proliferation
and/or promoting apoptosis, thus contributing to decreased gut lymphocyte homing and secretory IgA production. To test this hypothesis,
we compared the number of DCs found in the gut between mice fed a diet deficient in vitamin A, mice gavaged with all-trans retinoic acid
(ATRA; the biologically active vitamin A metabolite), and mice fed a control (vitamin A sufficient) diet. We found that the number of
myeloid CD103+ DCs was significantly decreased in the intestines of mice fed a diet deficient in dietary vitamin A and significantly increased
in the intestines of mice given ATRA through gavage. In the intestine, the myeloid CD103+ DC have the property of directing gut lymphocyte
homing and inducing IgA class switch. These cells also form clusters associated with intestinal lymphoid tissues and accordingly we observed
that the number of DC clusters was significantly decreased in mice fed a vitamin A deficient diet and significantly increased in mice given
ATRA by gavage. To evaluate the direct effects of vitamin A on DCs, we generated bone marrow derived myeloid DCs and evaluatedtheir
proliferation and apoptosis in response to ATRA or LE135, an inhibitor of ATRA signaling. We observed that DC proliferation was increased
in response to ATRA and decreased in response to LE135. These observations correlated with changes in expression in the apoptotic genes
Caspase 2 and Caspase 8 in response to ATRA or LE135. Our findings demonstrate a direct relationship between dietary vitamin A and the
maintenance of the gut DC population. Dietary vitamin A promotes the survival and proliferation of a subpopulation of gut DCs, which
then facilitate gut lymphocyte homing and secretory IgA production. Further discovery and verification of the role of DCs in the production
of IgA could ultimately lead to innovative approaches in lessening the effects of Vitamin A deficiency on the population.
TOP-DOWN AND BOTTOM-UP MEDIATION OF MULTIPLE TROPHIC CASCADES ACROSS A GRADIENT
OF INTERACTION STRENGTH.
1
1
Patrick Hanly , Kevin Smith , and Jonathan Chase1, Biology Department, Washington University, St. Louis, MO1.
Trophic cascades are ubiquitous in nature and are responsible for structuring a wide array of biological communities. Many communities,
however, are comprised of an intricate network of interacting species that lack discrete trophic levels and isolated cascading effects. We used
water-filled tree hole communities as a model system to help unravel the complex nature of trophic interactions. A fully factorial design with
two levels of mosquito larva predation (top-down influence), two levels of nutrient addition (bottom-up influence), and five levels of
drought-induced volume (i.e. the random encounter rate or interaction strength between organisms) was replicated five times for a total of
one hundred experimental tree hole communities. Principal components analysis (PCA) revealed three distinct trophic cascades that were
simultaneously responsible for explaining a large portion of the variance between communities. These observed cascading effects varied across
treatment groups with respect to the strength of interactions to structure the final observed communities. In conjunction to mediating trophic
cascades, these predator addition and nutrient addition treatments significantly altered how both bacterial and protist community compositions
responded to increasing strength in the interactions between species. These results reiterate the complexity of interactions that shape
communities but novelly demonstrate the importance of interaction strength.
39
DIFFERENTIAL EFFECTS OF THE RAB5 ISOFORMS ON CELL MOTILITY
Andrew Harding1, Pin-I Chen1, Philip Stahl2, Department of Cell Biology and Physiology, Washington University School of Medicine,
St. Louis, MO2.
Cell migration is essential for many biological processes, such as inflammatory responses. Rab5 GTPase has been implicated in regulating
the cytoskeletal dynamics that drive motility; however, it remains to be seen whether the three Rab5 isoforms (A, B, and C) are equally
involved in this regulation. To investigate this question, the three Rab5 isoforms were selectively knocked down in HeLa cells. Rab5C silencing
leads to uniform cell shape lacking well-defined leading edges. Rab5A silencing leads to a spread out morphology with extended lamellepodia.
Scratch wound assays were used to observe motility. Rab5C knockdowns were significantly less motile while Rab5A knockdowns displayed
increased motility. To observe these effects in a more physiologically relevant context, we have begun to use more motile monocytes and
macrophages. Upon differentiation into macrophages, both U937 cells and primary human monocytes and macrophages show a substantial
increase in Rab5A and Rab5C, whereas Rab5B levels stay the same. We expect this increase may correlate with increased motility in
macrophages. Boyden assays will be used to measure cell motility in U937 monocytes to observe the effects of Rab5 isoform knockdowns.
These results imply that Rab5C functions to promote cell migration whereas Rab5A inhibits it. We speculate that this regulation may be due
to Rab5 trafficking of the cell motility mediator Rac. Whether this or some other signaling pathway is the actual mechanism remains to be
seen.
EVOLUTION OF A SENSORY PATHWAY MEDIATING SOCIAL COMMUNICATION BEHAVIOR
IN MORMYRID ELECTRIC FISH
Saad Hasan1, Bruce Carlson1, Biology Department, Washington University, St. Louis, MO1.
Mormyrid fish use electric organ discharges (EODs) to communicate. EOD waveform is stereotyped within species, but can vary greatly
between species in duration and number of phases. The sequence of pulse intervals (SPI) varies and conveys the behavioral state of the sender.
Information about the EOD and SPI is first processed in the midbrain exterolateral nucleus, which is subdivided into anterior and posterior
regions (ELa and ELp) in the species studied so far. Despite the importance of this pathway in social communication behavior, there has been
no attempt to record evolutionary change in its structure. The purpose of this study is to quantify variation in ELa/ELp size throughout the
mormyrid family and relate this variation to species and signal diversity. To date, we have analyzed 50 µm horizontal sections of fixed brains
from 3 species in the subfamily Mormyrinae: Brienomyrus brachyistius (n=2), Pollimyrus adspersus (n=1), and the “Gabon-clade” Brienomyrus
longicaudatus (n=1); and 1 species in Petrocephalinae, Petrocephalus soudanensis (n=2). We found a clear division between ELa and ELp in
each species of Mormyrinae, but the Petrocephalinae EL was not subdivided. We calculated the total volume of EL, normalized by brain
mass, and obtained the following (in mm³/g): B. brachyistius: 3.17, 3.12; P. adspersus: 2.46; B. longicaudatus: 2.66; P. soudanensis: 0.31, 0.38.
The dramatic difference in EL volume and subspecialization between Petrocephalinae and Mormyrinae suggests an early divergence in
Knollenorgan pathway anatomy, which may relate to reduced EOD diversity among Petrocephalinae compared to Mormyrinae. Our data
also suggest a possible relationship between EL size and EOD duration in Mormyrinae, as the B. brachyistius EOD is an order of magnitude
longer than the P. adspersus EOD (1-2 ms vs. 100-200 µs): a larger EL may relate to the demands of processing information over longer
timescales. We also calculated the ratio of ELa/ELp volume among the Mormyrinae, and obtained the following: B. brachyistius: 1.44, 1.32;
P. adspersus: 1.97; B. longicaudatus: 2.43. B. longicaudatus is unique among our sample, as it is part of a rapidly diversifying species flock with
widespread EOD diversity. Its relatively large ELa/ELp ratio therefore suggests a possible relationship between sympatric species diversity and
relative ELa size, which supports a primary function of ELa in EOD waveform discrimination. Additional species will need to be analyzed
to fully test these hypotheses and reconstruct the evolution of this pathway throughout the mormyrid family. Behavioral studies are needed
to relate this variation to signal detection and discrimination abilities.
AGGREGATION STUDIES OF AMYLOID BETA PEPTIDE IN THE PRESENCE OF METAL CATIONS
AND METAL BINDING COMPOUNDS
Nicholas Hawco1, Liviu M. Mirica1, Chemistry Department, Washington University, St. Louis, MO1.
Alzheimer’s Disease (AD), the most prevalent and expensive neurodegenerative disorder, is characterized by the deposition of Amyloid Beta
(Aβ) peptide aggregates in the brains of diseased patients. The Aβ monomer, a 40-42 amino acid peptide, aggregates into large hydrophobic
fibrils through several potential mechanisms. These fibrils were initially thought to lead to the onset of AD, but recent evidence has indicated
that soluble Amyloid Beta oligomers, an intermediary in fibril formation, are most neurotoxic. Aggregation studies were performed with both
the 40 and 42 amino acid species in the presence or absence of metal cations and redox mediators, and the extent of aggregation was
monitored through UV and Thioflavin T fluorescent assays, as well as gel electrophoresis. Initial results show that preformation of Aβ trimers
dramatically alters the metal mediated aggregation process. This observation could have direct implications in the physiological role of soluble
Aβ oligomers in vivo. Bifunctional compounds were synthesized with the intent of binding to both metal ions and the beta sheet structure
of the peptide, and are currently being investigated in an attempt to develop an inhibitor to Aβ aggregation.
40
THE ROLE OF AUTOPHAGY GENES IN THE PATHOGENESIS OF CROHN’S DISEASE
Aaron L. Hecht1, Thaddeus S. Stappenbeck2, Biology Department, Washington University, St. Louis, MO1; Immunology and Pathology
Department, Washington University School of Medicine, St. Louis, MO2.
Crohn’s disease (CD) is an idiopathic, chronic inflammatory disease of the intestine. Recent genome wide association studies identified CD
susceptibility alleles for more than 30 genes including the autophagy gene ATG16L1. Autophagy is a cellular process triggered by nutrient
deprivation whereby organelles are recycled into basic molecular parts. We found that knockout of the related autophagy gene Atg5 in mouse
intestinal epithelium caused a loss of secretion from colonic goblet cells, thereby creating an absence of the critical mucus barrier between
the host and the intestinal microbiome.
My hypothesis is that dysfunctional autophagy (with loss of Atg5) is responsible for diminished goblet cell secretion, while the null
hypothesis is that Atg5 effects secretion through autophagy-independent means. To test this, I created an in vitro system through the stable
knockdown of ATG5 in a human goblet cell line. Preliminary results suggest that the knockdown cell line possesses similar traits to that of
knockout mouse goblet cells in regards to the transcript regulation, protein levels and cellular morphology. This cell line will provide a
system with which we can study the mechanism of the susceptibility allele and gain a better understanding of CD.
INTERACTIONS OF HOST CELLS WITH THE PATHOGENIC
FUNGUS CRYPTOCOCCUS NEOFORMANS
Elizabeth Held1, Tamara L. Doering2, Biology Department, Washington University, St. Louis, MO1; Department of Molecular
Microbiology, Washington University School of Medicine, St. Louis, MO2.
Cryptococcus neoformans is an opportunistic pathogen that can cause serious and sometimes fatal disease in immunocompromised individuals
and is responsible for over 600,000 deaths per year worldwide. Cryptococcosis is contracted by inhalation of the C. neoformans pathogen, a
basidiomycetous budding yeast that is surrounded by an extensive polysaccharide capsule. A critical part of the pathogenesis of cryptococcal
infection is the engulfment of the infective yeast cells by host phagocytic cells. To understand the virulence of C. neoformans it is important
to study how and why variations in this uptake can occur. Our group has developed a partly automated screening assay to assess the relative
host cell adherence and uptake of various mutant strains compared to wild type. Of particular interest in our screening were seventeen
mutants from a collection of insertional mutants that showed altered uptake and adherence phenotypes. The goal of this work was to further
confirm and characterize the defects in these insertional mutant strains. Starting with wild type cells, I independently deleted two of the genes
that had been implicated in the host pathogen interactions. In a separate approach I used RNA interference to reduce expression of fifteen
other implicated genes. Using both methods allowed comparison of the efficiency of these approaches for follow-up studies. It also offered
the possibility of success even if the targeted gene was essential (so deletion will not work) or highly expressed (so interference might be less
efficient). For the gene deletion project, I used a “split-marker” approach, which proved highly efficient. When tested, both deletion strains
I generated showed similar phenotypes to their corresponding insertional mutants in the original uptake and adherence assay. This confirmed
the role of the targeted genes in this critical process. For the RNAi studies, efficacy of the approach was confirmed by RT-PCR; adherence
and uptake assays are pending. This work will contribute to our knowledge of host-pathogen interactions important for a serious disease.
THE ROLE OF GDAP1 IN REGULATING MITOCHONDRIAL DYNAMICS IN
CHARCOT-MARIE-TOOTH NEUROPATHY
Sirui Jiang1, Albert Misko2, Iga Wegorzewska2, Robert Baloh2, Chemistry Department, Washington University, St. Louis, MO1;
Neurology Department, Washington University School of Medicine, St. Louis, MO2.
Charcot-Marie-Tooth (CMT) disease is an inherited peripheral neuropathy characterized by a dying back degeneration of the longest axon
in the body. CMT is estimated to affect 1 in 2,500 individuals, and manifests clinically as weakness with loss of sensation starting in the feet,
and progresses to involve the legs and hands leading to significant disability.
Mutations in the ganglioside-induced differentiation-associated protein 1 (GDAP1) lead to a subtype of CMT, called CMT4A. GDAP1
is an outer mitochondrial membrane protein with a suggested role in mitochondrial fission. Mutations in GDAP1 affect both Schwann cells,
the myelinating glia of the peripheral nervous system, and neurons. However, the effects of these mutations on the protein’s function and
their implications for axonal stability have yet to be characterized.
To elucidate the effects of GDAP1 mutants on axonal stability and mitochondrial function, we will express the GDAP1 disease mutants
in dorsal root ganglion (DRG) neurons, a disease relevant cell type. We will assess both morphology and dynamics of axonal mitochondria
as well as determine the integrity of the affected axons.
41
A CHARACTERIZATION OF MYELOID CELL INFILTRATION IN RESPONSE TO ANTIANGIOGENIC
TREATMENT IN A CONDITIONAL MODEL OF HIF-1 ACTIVATION
Joanna R. Kovalski1, Sunday S. Oladipupo2, and Jeffrey M. Arbeit2, Biology Department, Washington University in St. Louis, MO1;
Urology Division/Department of Surgery, Washington University in St. Louis School of Medicine, MO2.
Angiogenesis is a complex process dependent upon a host of local and systemic regulators. Under low oxygen conditions, upregulation of
HIF-1 is paramount to proximal and widespread mobilization of many attendant proangiogenic cell types. This process is a salient feature
of adult angiogenesis, which is exemplified by cancer malignancy and metastasis as well as ischemia. Using a conditional model of doxycycline-regulated expression of a constitutive, and oxygen-insensitive mutant HIF-1alphaP402/564A/N803A expressed from the basal keratinocytes, I
performed a time course analysis of myeloid cell infiltration by immunoflourescent cell type specific labeling on both untreated, and antiVEGFR1 and anti-VEGFR2 immunoblockade treated conventional mouse ear cross-sections. Substantial myeloid and mast cell infiltration,
with little corresponding CD8a+ T-cell accumulation, was apparent as early as day one. CD45+ hematopoietic cells, CD11b+ monocytes,
Gr1+ neutrophils and mast cells, identified as c-kit+, all reached maximum infiltration by day 30. To mechanistically probe our model, we
employed receptor-blocking antibodies, which prevent ligand binding to the extracelluar domain, blocking the signal through either
VEGFR1 or VEGFR2. We preformed a blockade against VEGFR2 with the antibody DC101 as well as VEGFR1 with the antibody MF-1,
in order to assess both the impact of VEGF signaling on blood vessel growth and the attendant myeloid cell response. Blockade of either
VEGFR1 or VEGFR2 from day 0-14 resulted in sizeable decrease in both CD45+ and CD11b+ myeloid cells down to the basal level seen
at day 0 or post- day 14 of HIF-1alpha transgene withdrawal. However, blockade of VEGFR2 from day 14-28 resulted in no abrogation of
CD45+ or CD11b+ myeloid cells compared to a typical day 30. Thus, during the proliferative phase from day 0-14 myeloid cell infiltration
and retention is largely mediated by VEGFR1 and VEGFR2, which is in contrast to the day 14-28, VEGFR2 independent, maintenance
phase. The high level of continual retention in the later stage, even under VEGFR2 blockade, suggests an important positive role for myeloid
cells in angiogenesis, and an adverse contribution to resistance of antiangiogeneic cancer therapies.
AVIAN CONE PHOTORECEPTORS TILE THE RETINA AS FIVE INDEPENDENT, SELF-ORGANIZING MOSAICS
Yoseph A. Kram, Stephanie Mantey, and Joseph C. Corbo2, Department of Pathology and Immunology, Washington University School
of Medicine, St. Louis, MO.
The avian retina possesses one of the most sophisticated cone photoreceptor systems among vertebrates. Birds have five types of cones including
four single cones which support tetrachromatic color vision and a double cone which is thought to mediate achromatic motion perception.
Despite this richness, very little is known about the spatial organization of avian cones and its adaptive significance.
Here we show that the five cone types of the chicken independently tile the retina as highly ordered mosaics with a characteristic spacing
between cones of the same type. Measures of topological order indicate that double cones are more highly ordered than single cones, possibly
reflecting their role in motion detection. Although cones show spacing interactions which are cell type-specific, all cone types use the same
density dependent yardstick to measure intercone distance. We propose a simple developmental model which can account for these observations.
We also show that a single parameter, the global regularity index, defines the regularity of all five cone mosaics. Lastly, we demonstrate
similar cone distributions in three additional avian species suggesting that these patterning principles are universal among birds.
Since regular photoreceptor spacing is critical for uniform sampling of visual space, the cone mosaics of the avian retina represent an elegant
example of the emergence of adaptive global patterning secondary to simple local interactions between individual photoreceptors. Our results
indicate that the evolutionary pressures which gave rise to the avian retina’s various adaptations for enhanced color discrimination also acted
to fine-tune its spatial sampling of color and luminance.
MIRNA SEQUENCE DIVERSITY IN BREAST AND PROSTATE CANCER TUMOR SAMPLES
Alina Kutsenko1, Min Young Kang2, Gregory Longmore2, Matthew Ellis2, Adam Kibel2, Scot Matkovich2, Gerald Dorn2, Biology Department,
Washington University, St. Louis, MO1; Pharmacogenomics Department, Washington University School of Medicine, St. Louis, MO2.
Discovered in 1993, microRNAs (miRNAs) regulate translation and message stability in a variety of fundamental processes such as development,
differentiation, cell proliferation, and apoptosis. Due to differential expression profiling, miRNAs have recently been implicated in many
human malignancies. While it is widely accepted that genetic mutations cause cancer, researchers have yet to determine if mutations in
miRNAs result in similar outcomes. HYPOTHESIS: Mutations in functionally significant miRNAs are vital to cancer development.
APPROACH: Searched for mutations in a set of 59 miRNAs (determined from expression profiling to be implicated in cancer development)
by sampling tumor and normal sets as well as the general population. Then used case control analysis to determine associations between
single nucleotide polymorphisms (SNPs) and cancer development. METHODS: Used PCR to amplify the DNA and Illumina ultra-high
throughput sequencing to discover SNPs. RESULTS: While data for the tumor normal samples is currently in the sequencing stage, data on
2629 subjects from the peripheral blood of the general population has yielded 86 SNPs in the stem loop sequences of the miRNAs, 18 SNPs
in the mature miRNA sequences, 9 SNPs in the seed sequences of the miRNAs, and 4 invariant miRNAs.
42
THE EFFECTS OF AN INVASIVE PLANT ON TERRESTRIAL AMPHIBIAN COMMUNITIES
Eric Lee1, James Watling1, John Orrock1, Biology Department, Washington University, St. Louis, MO1.
Humans have affected the global ecosystem by introducing invasive species, which accumulate rapidly and adversely affect local fauna. The exotic plant,
Lonicera maackii, is widespread and abundant around Saint Louis. We are interested in characterizing its effects on animals. Because amphibians are
exposed to L. maackii in both aqueous and terrestrial environments and are experiencing global population declines, they are a vital taxon to study.
Lonicera maackii adds a dense shrub layer to forest where it invades. Areas with high L. maackii density are expected to have a microclimate
with higher humidity and lower, less variable temperature compared to low density areas. We expected the adult terrestrial phase to be positively
influenced by the increased humidity and decreased temperature in areas of high L. maackii density. We hypothesize that areas with high
density will have greater numbers and lower biodiversity.
Twelve pitfall trap arrays were installed at Busch Memorial Conservation Area; six each in areas with high and low L. maackii density. We
sampled over 1000 individuals of nine species from March to July 2009. Although microclimate did not vary as expected between invaded
and un-invaded plots, we did see differences in the amphibian communities with changing L. maackii density.
HIGH-YIELD EXPRESSION OF RECOMBINANT MALARIA INVASION PROTEINS
Daniel Lin , Nichole Salinas2, Niraj Tolia2, Department of Biomedical Engineering, Washington University, St. Louis, MO1; Department
1
of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO2.
Malaria causes more than 300 million cases of clinical disease and 2 million deaths a year. Erythrocyte invasion is the stage of disease
responsible for all of malaria’s clinical symptoms and its lethality. The most lethal form of malaria is caused by Plasmodium falciparum.
Plasmodium species possess several ligands that are implicated in erythrocyte invasion and are capable of recognizing and binding erythrocytes.
These erythrocyte invasion proteins belong to two families, the EBL family and the RBL family. P. falciparum possesses several members of
the EBL family, including EBA-175, EBA-181, and EBA-140. The mechanism by which the EBL family binds erythrocyte membrane
receptors is not well understood. Studies on EBA-140 and EBA-181 structure, dimerization, and binding require high quantities of pure,
soluble protein. Here, it is shown that EBA-140, which has been previously resistant to recombinant expression, can be expressed with high
yield and purity. Such expression can be accomplished by expressing a synthetic, codon-optimized gene in E. coli into inclusion bodies. The
protein can then be isolated from the inclusion bodies, refolded, and purified with a HPLC at high yield and high purity.
DESIGN OF A DUAL-FUNCTION MRI AND NIR OPTICAL TUMOR PROBE
Franck Lin, Samuel Achilefu
Multi-modality noninvasive in vivo imaging has many applications in both clinical and research areas. Specifically, a dual-function MRI and
NIR optical probe can take advantage of the spacial resolution and penetration of MRI and the high sensitivity of NIR optical imaging. The
purpose of this project was to design and synthesize this type of probe with polyacrylic acid-coated iron-oxide nanoparticles, cypate fluorescence
dye, and an αvβ4 integrin targeting molecule, the RGD peptide motif. Ultimately, the independently verified and partially characterized subunits of the probe could not be joined together with simple peptide chemistry due to the unique solubility properties of the sub-units.
COMMERCIALIZATION POTENTIAL AND INSECTICIDAL CAPACITY OF FURCRAEA ANDINA EXTRACT
Nathaniel Markman1, Rainer W. Bussmann1,2, Biology Department, Washington University, St. Louis1; William L. Brown Center,
Missouri Botanical Garden2.
Furcraea andina (Andean Agave) is a widely cultivated fiber in the Intag Region of Ecuador. The extract is a by-product of existing fiber
production and thus its commercialization could create additional revenue for farmers. The Intag region is a biodiversity hotspot, and
currently open-pit copper mining proposed by foreign companies poses a threat to the ecological stability of this region and its farming
communities. Revenue from selling a Furcraea andina extract could create an incentive to forego mining, support local farmers, and as a
natural/biodegradable insecticide, improve health conditions of workers in the floriculture industry of Ecuador.
Several experiments were carried out to test the extracts efficacy as an insecticide. The phytochemical analysis showed that Furcraea andina
leaves are an abundant source of saponins. These compounds lead to a surfactant effect which is the likely reason why Furcraea andina extract
can function as an insecticide. The extract was applied to several agricultural pests; Leptophobia pieridae, Spodoptera frugiperda, Liriomyza
huidobrensis, and Nematoda. The nematodes were most affected and could be eliminated even at low concentrations (25%).
A business model was developed for selling the extract from communities in Intag to larger flower plantations outside the region.
Interviews with community farmers helped determine a fair selling price. Because the extract is an easy to collect by-product of fiber production,
it could be sold at a price competitive with conventional nemocides. Correspondence with area flower plantations indicated a large demand
for a natural biodegradable nematocide.
43
RECEPTOR SIGNALING IN MIGRAINE:
SCREENING FOR PROTEIN INTERACTIONS WITH HUMAN 5HT RECEPTORS IN VIVO
Sylvester Marshall III1, Ping Liu, Ph.D.2, Yu-Qing Cao, Ph.D.2, Biology Department, Washington University, St. Louis, MO1;
Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO2.
Migraine is a neurological disease, which can be correlated with low levels of the neurotransmitter serotonin as one of its causes. The binding
of serotonin to several subtypes of the human 5-hydroxytryptamine 1 receptors (notably h5HT1B, h5HT1D and h5HT1F), which are
located in the brain and cerebral blood vessels, mediates neural inhibition and vasoconstriction via signaling pathways. The majority of h5HT
receptors are G-protein-coupled receptors with seven transmembrane domains, which are connected by intracellular and extracellular protein
loops. The h5HT receptor intracellular loops contain potential sites for protein interactions, such as with the anchor protein GNB2L1, which
contains 7 WD repeats. We performed a yeast 2 hybrid screening using the 3rd intracellular loop (i3L) of the h5HT1D receptor as bait, and
found a protein interaction with the candidate 2-7’ protein truncation of GNB2L1. The significance of finding a protein interaction will not
only help us better understand the functions of these proteins, but may lead toward the development of anti-migraine drugs of improved efficacy.
To test if the full length GNB2L1 protein interacts with the h5HT1D receptor i3L, we generated plasmid DNA constructs for the
GNB2L1 protein full length and truncations (1’, 1-4’, 2-7’, 5-7’), and performed a yeast 2 hybrid binding assay. We found protein interactions
between the h5HT1D receptor i3L and the 5-7’ GNB2L1 protein truncation, but surprisingly no interaction was observed with the full
length GNB2L1 protein. To explore this potential protein interaction further, we have transfected h5HT1D receptor i3L and full length
GNB2L1 plasmid DNA constructs into mammalian cells and plan to perform a co-immunoprecipitation experiment.
THE ROLE OF SDEA IN INTRACELLULAR REPLICATION OF LEGIONELLA PNEUMOPHILA:
FINDING A SUPPRESSOR OF TOXICITY IN YEAST
Brian Mau1, Kwang Cheol Jeong2, Joseph Vogel2, Biology Department, Washington University, St. Louis, MO1; Dept. of Molecular
Microbiology, Washington University School of Medicine, St. Louis, MO2.
Legionella pneumophila is a pathogen that causes a pneumonia-like disease called Legionnaires’ disease. L. pneumophila survives and replicates
inside alveolar macrophages by preventing fusion of the Legionella-containing vacuole (LCV) with the lysosome. L. pneumophila encodes a
type IV secretion system (T4SS) called Dot/Icm (defect in organelle trafficking/intracellular multiplication) that is required for intracellular
survival of this pathogen. The Dot/Icm T4SS exports a large number of bacterial proteins (effectors) into the host cell in order to alter the
host’s endocytic pathway. For most Dot/Icm substrates, deletion of the gene does not result in a growth defect of L. pneumophila within a
host cell. However, for one family of substrates called the SidE family (SidE, SdeA, SdeB, and SdeC), deletion of the entire family causes a
significant intracellular growth defect within amoebae, the environmental host of L. pneumophila.
The goal of my project was to determine the function of SdeA. The approach was based on the isolation of suppressors that alleviate the
toxicity when SdeA is expressed in yeast. Based on many examples of toxins, we hypothesized that SdeA toxicity in yeast is related to its function
during infection of host cells and the identification of suppressors may reveal the target of SdeA toxicity. I attempted to isolate suppressors
by selecting for high copy yeast genome plasmids that rescued yeast from the toxic effects of SdeA expression. In addition, I directly selected
for spontaneous chromosomal yeast mutations that allowed yeast to survive in the presence of SdeA.
Although I did not find any high copy suppressors or chromosomal yeast mutations that suppressed SdeA toxicity, I was able to isolate
approximately a dozen spontaneous mutations in the sdeA gene that were no longer toxic when expressed in yeast. Upon further
characterization that included PCR, sequencing and westerns, I discovered one sdeA mutant that produces full-length protein and contains
a single amino acid change (Thr to Ile of amino acid 827). Interestingly, this mutant is unable to complement the intracellular growth defect
of a L. pneumophila sidE family deletion and represents the first sdeA point mutation ever isolated. Further characterization of this mutant
will likely be instrumental in identifying the function of SdeA. Moreover, due to the technical difficulty in directly isolating mutations that
inactivate L. pneumophila Dot/Icm substrates during intracellular growth, this approach may be applicable to the characterization of other
L. pneumophila T4SS substrates.
NITROSOTHIOLS REGULATE RED BLOOD CELL ANTIOXIDANT DEFENSE
Dylan McLaughlin1, Stephen Rogers1, and Allan Doctor1,2, 1Department of Pediatrics and 2Department of Biochemistry and Molecular
Biophysics, Washington University in St. Louis.
Red blood cell (RBC) antioxidant defense is reliant on reduced glutathione (GSH) to scavenge free radicals. Maintenance of GSH is regulated
via glucose metabolism, of which there are two main pathways: the Embden Meyerhof pathway (EMP) and the Hexose Monophosphate
pathway (HMP). Glucose flux through either pathway is governed by protein interactions at the cytoplasmic domain of Band 3 membrane
protein (cdB3). Deoxyhemoglobin (deoxyHb) competes with key EMP enzymes for binding to the cdB3. Binding of deoxyHb releases and
activates the EMP enzymes, enhancing glucose flux via this pathway. Notably, the EMP does not regenerate nicotinamide adenine dinucleotide
44
phosphate (NADPH), which is essential for glutathione recycling. Consequently, under hypoxic conditions (which promote sustained
deoxyHb/cdB3 binding), NADPH and GSH recycling are limited, which undermines RBC antioxidant defense.
Thiol based NO signaling is central to the generation of appropriate physiologic responses to hypoxia. In this process, NO+ adducts to
specific reactive cysteine thiols (S-nitrosylation), resulting in altered signaling or protein function. Several RBC proteins (including key
enzymes) contain redox active regulatory cysteine thiols known to be regulated by NO. We hypothesized that NO+ would reverse the constraint
upon NADPH and GSH recycling in hypoxic RBCs via S-nitrosylation of key proteins which regulate glucose metabolism, augmenting flux
via the HMP, and restoring NADPH and GSH recycling capacity under conditions of oxidative stress.
In order to develop a physiologically relevant model, control experiments were performed. We identified several key variables including
the bathing glucose concentration, hematocrit (Hct), the oxidant stress and nitrosothiol concentration. Having optimized these conditions,
human RBCs were washed in PBS with 6mmol/L glucose and then exposed (or not) to cys/cysNO donor (1:250 NO:Hb ratio). Excess donor
was washed off prior to resuspension of the RBCs at 40% Hct. RBCs were fully oxygenated (21% O2; 7% CO2) for 5 minutes prior to
desaturation (0% O2; 7% CO2). Samples were removed at time intervals to obtain saturations spanning the whole hemoglobin saturation
curve (>95% to < 10%). Samples were subsequently studied under oxidative loading conditions (1.5mM hypoxanthine/0.2 units per ml
xanthine oxidase). Antioxidant defense was measured by spectrophotometrically determining the ratio of GSH to glutathione disulfide
(GSSG) and the ratio of NADPH to NADP. We have found that CysNO partially rescues hypoxic RBCs in the presence of oxidative stress.
The data suggests that NO+ regulates glycolytic pathway dominance, ultimately enabling NADPH and GSH recycling under hypoxic
conditions. Future experiments will determine the specific proteins which undergo nitrosylation (in order to identify the mechanism of
action) and also if other NO species, such as NO radical or NO-, have similar effects.
THE AMINO ACIDS UPSTREAM OF NH(2)-TERMINAL DILEUCINE MOTIF
PLAY A ROLE IN REGULATING THE INTRACELLULAR SORTING OF
THE CLASS III TRANSPORTERS GLUT8 AND GLUT12.
Mitch Otu1, Lauren Flessner2 and Kelle Moley2, Psychology Department, Washington University in St. Louis1; Department of Obstetrics
and Gynecology, Washington University School of Medicine, St. Louis, MO2.
The transport of glucose across cell membranes is mediated by facilitative glucose transporters (GLUTs). GLUT12 is predominantly
expressed in insulin-sensitive tissues and studies in our lab and in others have suggested that GLUT12 may be insulin-responsive. Both
GLUT12 and GLUT8 contain a putative [DE]XXXL[LI] targeting motif that is believed to facilitate the trafficking of proteins to numerous
cellular compartments or to the cell surface through interactions with different adaptor proteins (APs). GLUT8 is directed to late
endosomal/lysosomal compartments via its interactions with AP-1 and AP-2 while GLUT12 is directed to the Golgi network and the plasma
membrane. Furthermore, GLUT8 and GLUT12 exhibit dramatic differences in trafficking from the PM. Whereas GLUT8 is internalized
following its expression at the cell surface, GLUT12 remains largely associated with the PM.
To further explore its trafficking mechanisms, we created mutant constructs to identify a potential role for GLUT12’s dileucine motif in
regulating its intracellular sorting. We show that the amino acids immediately upstream of the LL motif influence the cell surface expression
of GLUT12. Our data specifically suggests that the amino acids upstream of the dileucine motif influence the affinity of APs for GLUT8
and GLUT12. We conclude that the mechanisms governing the intracellular sorting of GLUT12 are distinct from those regulating the sorting
of GLUT8.
MECHANISMS THAT EXPLAIN UNEVEN DISTRIBUTIONS OF IXODES SCAPULARIS
BETWEEN S. UNDULATUS AND P. LEUCOPUSY
Genevieve Pang1, Brian F. Allan1, Jonathan M. Chase1, Biology Department, Washington University, St. Louis, MO1, Tyson Research Center1.
Ticks are common vectors of zoonotic diseases, taking blood-meals from a wide variety of animal hosts and transferring these pathogens to
humans. According to previous studies, a variety of factors (i.e. parasite-host encounter rates, host choice, and host behaviors) can influence
how ticks distribute among hosts. In order to address the influence of these factors, we conducted a three-part study that investigated the
impact of abiotic stress (i.e. heat) on larval tick questing behavior, the impact of stress on host choice, and the influence of each host species
on larval tick survival. The questing behavior of larval ticks varied significantly with stress. Also, larval ticks did not exhibit host preference
unless exposed to stress, in which they oriented significantly towards mice. Lastly, mice produced a greater proportion of larvae that
successfully fed to repletion. Thus, both heat-induced stress and host behavior appear to play a role in how larval ticks distribute between
hosts. Since host species vary in their competency to transmit pathogens to ticks, a better understanding of the mechanisms that influence
tick-host interactions is of critical importance to the future management of tick-borne disease.
45
EVALUATING THE POTENTIAL ROLE OF GLYPICAN 3 AS A CORECEPTOR
FOR FIBROBLAST GROWTH FACTOR RECEPTOR-3 IN BONE GROWTH AND DEVELOPMENT
Anthony Pham1, Beth Viviano2, Scott Saunders2, Michelle Wong2, Biology Department, Washington University, St. Louis, MO1;
Pediatrics Department, Washington University School of Medicine, St. Louis, MO2.
Heperan Sulfate Proteoglycans (HSPG) are glycoprotiens that are involved a variety of molecular cellular processes throughout the body. A
member of this family, Glypican 3 (Gpc3), which is expressed on the cell surface, is linked to both pre- and post-natal overgrowth in humans
and mice, yet the molecular mechanism occurring in the growth plates of long bones that causes these symptoms has yet to be fully investigated.
Fibroblast Growth Factor Receptor 3 (FGFR3) is an important upstream modulator of a feedback loop regulating proliferation and
differentiation of the chondrocytes of the growth plate. Since, loss of either FGFR3 or GPC3 function leads to bone overgrowth symptoms
and similar changes in IHH and Ptc mRNA expression, it led us to hypothesize that Gpc3 is the specific HSPG’s coreceptor for FGFR3 in
bone and is required for FGFR3 function on the growth plate.
We attempted to confirm our hypothesis through in vivo approaches, using existing knockout mouse lines for both Gpc3 and Fgfr3 to
perform genetic interaction experiments between the two genes. The initial collected data suggests that, in fact, Gpc3 may not be a coreceptor
for Fgfr3 at E18.5, but a genetic interaction occurring post-natally has yet to be definitively proven. Further genetic interactions experiments
can help prove whether or not Gpc3 is a coreceptor for Fgfr3 post-natally.
THE FABRICATION OF A DEVICE FOR DIRECT ELECTRICAL
DETECTION OF PROTEINS AT THE MICROSCALE
Michael R. Post, Matthew K. Strulson, Joshua A. Maurer. Chemistry Department, Washington University in St. Louis.
The current state of the art for protein detection utilizes assays in which small dye molecules bind to protein. Tests such as these depend on
photospectroscopy and are often affected by the presence of other small molecules in solution. Furthermore, these assays are unable to test
for specific protein. The goal of this device is to rapidly test small volumes of solution for protein using electric detection in a way that is
rapid, reproducible, and unaffected by other molecules in solution.
The device consists of two copper electrodes patterned onto a glass substrate using photolithography. The electrodes have wires which run
parallel to each other, but with a defined space between them. The glass substrate is coated in a monolayer of octadecyltrichlorosilane (OTS).
A microfluidics channel in PDMS is used to deliver small quantities of fluid across the parallel wires. The OTS monolayer will adsorb any
protein present in solution. Silver ions passed through the channel will bind to the protein, and when reduced can complete a circuit between
the two wires. A resistance measurement is made to determine whether the circuit is complete and protein is present. Future research will
work to develop a more durable model and investigate the use of antibodies to detect specific proteins.
EXPRESSION AND PURIFICATION OF
LEGIONELLA PNEUMOPHILIA COMPLEXES
Aditya Radhakrishnan1, Jacob Zahm2, Niraj Tolia2, Department of Biomedical Engineering, Washington University, St. Louis, MO1;
Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO2.
Legionella pneumophila, the organism responsible for Legionnaire’s disease, directs changes in its host cells by a coordinated effort of a multitude
of proteins. L. pneumophila employs a Dot/Icm type IV secretion system (T4SS) to release large quantities of protein substrates into alveolar
macrophage host cells, affecting phagosome trafficking. This modification of host endocytic pathways enables L. pneumophila to replicate in
the host cell. IcmS, a type IV adaptor protein, forms a heterodimer with IcmW, another adaptor protein, to function as a secretion
chaperone for certain protein substrates. IcmS also interacts with the virulence factor protein LvgA to form another unique type IV adaptor
complex. The mechanism by which these adaptors confer host specificity is not known. To study the structural properties of these adaptors
as well as the conformational changes that guide dimerization of the IcmS-IcmW and IcmS-LvgA complexes, large amounts of pure protein
are required to conduct crystallization studies. Soluble expression of these protein complexes in Escheria coli results in high quantities of largely
pure protein. From this point, the protein complexes are purified using ion-exchange chromatography and gel filtration chromatography to
obtain protein at high purity.
46
EXPRESSION OF DIFFERENT IONIC CHANNEL PROTEINS THROUGH
THE VENTRICULAR WALL OF NORMAL AND FAILING HUMAN HEARTS
Vinod K. Ravikumar, Alexey V. Glukhov, Vadim V. Fedorov, Igor R. Efimov, Department of Biomedical Engineering,
Washington University, St. Louis, MO
Heart failure (HF) is a condition of the heart impairing its structure and/or function of providing appropriate blood flow to the entire body.
HF is a common cause of death, claiming 200,000 deaths in the United States alone, half of which stem from ventricular tachyarrhythmias.
HF results in electrophysiological (EP) remodeling which includes the changes in expression of ion channel proteins and forms the functional
substrate for arrhythmogenesis. Currently, HF, and HF-associated arrhythmias in particular, are largely untreated due to difficulty in
interpreting symptoms to lead to an appropriate diagnosis, and a large number of treatments are diet-based since our limited knowledge of
arrhythmia at the molecular level prevents us from creating ion channel specific drugs to cure such HF related diseases.
Abnormal conduction believed to be the cause of the sudden cardial death in HF. Unidirectional conduction block is a prerequisite for
reentry and conduction slowing is typically a key predisposing factor for conduction block. To examine the potential molecular mechanisms
of HF-associated conduction abnormalities, the immunofluorescent mapping was used to characterize the expression of Connexin 43 (Cx43),
the principal gap junction protein found in ventricular myocardium.
Tissue from posterior-lateral left ventricular free wall from failing (n=5) and non-failing (n=5) human heart was studied with immunohistochemistry. Failing hearts with different types of cardiomyopathy were obtained during transplantation at the Barnes-Jewish Hospital,
Washington University in Saint Louis. For control, non-failing donor hearts was used. Tissue was optically mapped and then saved for
immunostaining. Our goal was to characterize transmural expression of Cx43 and correlate it with functional EP data observed previously.
Three different regions (epi-, mid- and endocardium) were sectioned parallel to the epicardial surface and double-stained with
Rb-anti-Cx43 (Sigma, 1:1000) and Ms-anti-α-actinin (Sigma,1:1600) antibodies. And subsequently, histology was used to estimate the level
of fibrosis in the failing and non-failing hearts.
The epicardial Cx43 density in both non-failing and failing hearts was found to be significantly decreased compared with the
midmyocardial and endocardial expression. HF remodeling resulted in a significant decrease of relative transmural expression of Cx43 at the
subepicardium. Midmyocardial and subendocardial Cx43 tended to downregulate as well in failing hearts, but the difference with nonfailing hearts did not reach statistical significance (by 34% (p<0.05) vs. 17% and 9% (NS), respectively). The level of fibrosis was found to
be greater (by 45%) in the failing hearts in all transmural regions.
We showed for the first time the HF-associated changes in Cx43 expression which can be responsible for EP remodeling observed
previously with optical mapping. Our future studies will focus on the investigation of the underlying mechanisms of gap junction remodeling
and examine the role of connexin-interacting proteins (i.e. N-Cadherin, zonula occludens-1 (ZO-1) et al.).
DUAL FREQUENCY TRANSMIT AND RECEIVE SURFACE COILS FOR MRI SCANNERS
Benton Reynolds2, Greg Lanza2, Frank Hockett2, Biomedical Engineering Department, Washington University, St. Louis, MO2;
Cardiology Department, Washington University School of Medicine, St. Louis, MO2.
An MRI machine produces a magnetic field to orient the spin of atoms in the body, and then another magnetic field pushes the orientation
of the spin in another direction. The frequency of this magnetic field determines which atoms change direction. Typically, MRI machines
focus only on lone proton atoms, or hydrogen atoms. However, in an attempt to gain resolution and clarity of images, it is desirable to scan
for fluorine atoms as well. Doing this requires a dual-frequency coil that can transmit and receive magnetic field information from both proton
and fluorine atoms. This was done by designing a circuit board with components that create a magnetic field for both proton and fluorine
frequencies. After designing, calculating, and prototyping were done for this coil, testing was performed on phantom rats and mice. Phantoms
are chemically and dimensionally similar to the real thing, but are easier to use. The images produced using the new MRI surface coil were
of high quality. This will be useful for scanning for tumors in the future, especially considering the increased flexibility of a fluorine scan.
SINGLE MOLECULE IMAGE DECONVOLUTION
Samuel Robinson, Yan Mei Wang
My work this summer directly dealt with the SMID (single molecule image deconvolution) technique being employed by Dr. Wang’s lab.
My work ranged from sourcing and eliminating impurities in our oxygen scavenger and buffer solutions we use to image (using TIRF-total
internal reflection fluorescence) to modifying matlab programs to simulate a rotating dimer at various distances of separation between molecules.
The work typically culminated in pixel and intensity analysis of video I had taken to yield relevant data (i.e. diffusion coefficients, bleaching
times for impurities, etc.)
47
IMPROVED PHOTOSYNTHETIC PRODUCTIVITY FOR RHODOBACTER SPHAEROIDES VIA SYNTHETIC
REGULATION OF THE LIGHT HARVESTING ANTENNA LH2.
Jacob Rubens1, Jaffre Athman1, Jacob Cecil1, Stephanie Chang1, Brendan Cummings2, Colin Foley1, Jeff Knudsen3, Alice Meng2,
Thomas Stevens2, Christine Kirmaier4, Yinjie Tang3, Robert Blankenship1,4, Biology Department, Washington University, St. Louis, MO1;
Department of Biomedical Engineering, Washington University St. Louis, MO2; Department of Energy, Environmental & Chemical
Engineering, Washington University, St. Louis, MO3; Department of Chemistry, Washington University, St. Louis, MO4.
Photosynthetic light harvesting antennas function to collect light and transfer energy to a reaction center for photochemistry. Phototrophs
evolved large antennas to compete for photons in natural environments where light is scarce. Consequently, cells at the surface of
photobioreactors over-absorb light, leading to attenuated photobioreactor light penetration and starving cells on the interior of photons. This
reduction of photosynthetic productivity has been identified as the primary impediment to improving photobioreactor efficiency. While
reduction of antenna size improves photosynthetic productivity, current approaches to this end uniformly truncate antennas and are difficult
to manipulate from the perspective of bioengineering. We aim to create a modifiable system to optimize antenna size throughout the bioreactor
by utilizing a synthetic regulatory mechanism that correlates expression of the pucB/A LH2 antenna genes with incident light intensity. This
new application of synthetic biology serves to transform the science of antenna reduction into the engineering of antenna optimization.
CYTOSKELETAL DYNAMICS IN 3D
Pascal M. Schaefer1, Guy M. Genin2, Biology Department, Washington University, St. Louis, MO1; Mechanical Engineering
Department, Washington University, St. Louis, MO2.
Dynamic mechanical properties of fibroblast cells in two-dimensional culture are driven by coupling between focal adhesion assemblies and
actin stress fibers. However, cells in two-dimensional culture appear to have mechanical properties that differ drastically from those of cells in
natural three-dimensional environments. The lack of existing measurements in three dimensions led us to design the following experiments.
We developed tissue constructs with fibroblast cells containing fluorescently labeled actin and vinculin, and that remodel the extracellular
matrix to develop a natural three-dimensional environment. Confocal fluorescence images of the stained focal adhesion assemblies were compared
to images from fixed and stained assemblies to ensure that they were qualitatively similar; mechanical responses of cells and extracellular
matrix were compared to tissue constructs containing no labeling. We imaged in real time the effects of mechanical stretch on focal adhesion
and stress fiber dynamics to investigate whether focal adhesions will grow with application of mechanical stretch to the tissue constructs, and
disassemble in the cases of insufficient or excessive mechanical stretch.
We found that the dynamics of stress fibers is highly dependent upon the mechanical environment of a cell.
DOES EUTROPHICATION CONTRIBUTE TO DISEASE EMERGENCE?
A CASE STUDY OF AN EMERGING AMPHIBIAN PATHOGEN
Vanessa Schroeder1, Kevin Smith1,2, Jon Chase1,2, Biology Department, Washington University, St. Louis, MO1; Tyson Research Center,
Washington University, St. Louis, MO2.
An emerging amphibian pathogen, the chytrid fungus known as Batrachochytrium dendrobatidis (Bd), is a known agent of global amphibian
declines and extinctions. Despite the large body of work involving Bd, few studies exist examining why Bd is located sporadically across habitats.
We addressed the relationship between aquatic nutrients and presence of Bd, examining whether eutrophication-induced alternative
stable states affect the establishment of Bd and modify its effect on the tadpoles of the gray tree frog, Hyla versicolor. We conducted a
large-scale pond survey throughout Missouri, measuring total Nitrogen and Phosphorus concentrations of each pond and collecting tissue
samples from tadpoles to determine the presence or absence of Bd through histology. These preliminary data suggest that there is no
correlation between Nitrogen and Phosphorus presence and the percent of Hyla tadpoles infected with Bd.
We are currently investigating the prevalence rates of larger amphibian species in the Rana genus in thirty additional ponds. Anthropogenic
eutrophication due to pollution and increased use of fertilizers is now a common form of global change, and a better understanding of how
nutrient loading affects aquatic systems and declining amphibians is essential to the conservation of these highly endangered systems.
MRNA EXPRESSION OF CALPAIN 10 IN LG/J AND SM/J MICE
Xin (Cissy) Si1, James Cheverud2, Elizabeth Norgard2, Biology Department, Washington University, St. Louis, MO1; Anatomy and
Neurobiology Department, Washington University School of Medicine, St. Louis, MO2.
Calpain 10 is part of a family of intracellular calcium- activated cysteine proteases that is ubiquitously expressed in low levels in all tissues. It has
been though to play a role in type 2 diabetes due to the presence of calpain 10 mRNA in pancreatic islets, muscle, and liver cells, which are the
three most important tissues controlling glucose homeostasis. We are interested in how this gene functions as a type 2 diabetes gene and its role
48
in variation in obesity. To do this, we compared mRNA expression levels in various tissues of male and female Lg/J and Sm/J mice fed high and
low fat diets using quantitative reverse transcriptase (qRT) PCR. Using Systat, analysis of ANOVA, we quantified the expression differences.
Further research will involve using allele specific qRT-PCR to determine the expression difference between the Lg and Sm phenotype in an F34
Lg X Sm intercross.
Knowing how calpain 10 is up or down regulated will help to determine further hypotheses as to what role calpain 10 plays in variation in
obesity. Ultimately, the results of this analysis will provide additional insight into the genetic variations of dietary-induced obesity in different
populations.
ADAPTIVE AND STABLE MECHANISMS FOR TOP-DOWN CONTROL
OF VISUOSPATIAL ATTENTION IN HUMANS.
Joshua S. Siegel1, Steve E. Petersen1,2, Washington University, St. Louis, MO1, Washington University School of Medicine, St. Louis, MO1,2.
Humans possess a remarkable ability to perform complex goal-oriented tasks with the flexibility to switch from one task to another. This ability is
subsumed by specific task-control regions of the brain. One of the capacities that facilitates goal-oriented behavior is ‘top-down control of
visuospatial attention’, in which processing of visual information is altered by signals from task-control regions in response to varying task
demands or stimuli.
A recent neural model suggests that task-control regions are organized into two distinct networks. The first is implicated in stable task-set
control over an extended timescale, while the second is implicated in trial-by-trial control of adaptive task performance. Our experiment
explores the different ways in which the two networks exert top-down control on visuospatial attention.
In our experiment, human subjects fixate on the center of a screen and perform a visual discrimination task. Arrows cue subjects’ attention
to a spatial location for either 1) single trials, or 2) periods of multiple trials (blocks). Behavioral results show that attention improves response
time equally under both conditions. Next, we will give the test to subjects undergoing fMRI scans and look at temporal variation in
activity in the two task networks within trials and throughout task blocks.
TREATMENT OF OCULAR MELANOMA CELLS WITH A MEK 1/2 INHIBITOR
IDENTIFIES A DISTINCT GENE REGULATION PROFILE ASSOCIATED
WITH GNAQ MUTATION
Aeron Small1, J. William Harbour2, Katie Golder2, Mike Onken2, Biology Department, Washington University, St. Louis, MO1;
Department of Ocular Oncology, Washington University School of Medicine, St. Louis, MO2.
Guanine nucleotide-binding protein alpha-q (GNAQ) encodes the alpha subunit of a heterotrimeric GTP-binding protein that couples
G-protein-coupled receptor signaling to the RAF/MEK/ERK pathway. Oncogenic mutation at codon 209 of GNAQ has been found to
occur in 49% of primary uveal melanomas (UM) making GNAQ the most common known oncogenic mutation of this cancer to date.
Mutation at codon 209 results in constitutive activation of GNAQ, and consequently increased activation of the RAF/MEK/ERK pathway,
a signal transduction pathway important for regulation of cell growth and a common therapeutic target for cancer treatment.
Though GNAQ is mutated in almost half of primary uveal melanoma cells, there is yet to be found an analogous mutation in the remaining
51% of tumors. In a previous study, the Harbour lab sequenced 23 genes within the RAF/MEK/ERK pathway to probe for mutation but
found no further oncogenic mutations. Interestingly, there were no statistically relevant differences found in gene expression between the
GNAQ mutant and wildtype tumors.
To probe for differences in gene expression between GNAQ mutant and wild type cells, with the potential to narrow possibilities for a
second mutation in the RAF/MEK/ERK pathway, a more functional approach was carried out. Three ocular melanoma cell lines, MEL202
and 92.1 cells with the GNAQ mutation, and OCM1A cells without the GNAQ mutation, were treated with an inhibitor of MEK1/2. Gene
expression was analyzed over time post treatment with the MEK inhibitor and compared with a control of no treatment at each time-point
for a small selection of genes. Genes were chosen that were known targets of the RAF/MEK/ERK pathway and included CCND1, MYC,
DUSP6, SPRY2, ETV1, and EGR3. Results indicate that GNAQ mutant and wild type cells respond differently over time to the inhibition
of MEK1/2, with GNAQ mutant cells recovering gene expression at late time points, while these same gene expression profiles continuously
drop in GNAQ wild type cells. Thus, inhibition of MEK1/2 identifies genes that are differentially regulated by GNAQ mutation.
Understanding the mechanism of MEK1/2 inhibition in the context of differential gene regulation between GNAQ mutant and wildtype
cells may lead to the identification of the analogous mutation in the wildtype cell lines.
49
ULTRASTRUCTURAL CONFIRMATION OF SYNUCLEIN LOCALIZATION IN AUDITORY TISSUE
USING IMMUNOLABELING AND ELECTRON MICROSCOPY
Apollo Stacy1, Brian Faddis2, Biology Department, Washington University, St. Louis, MO1; Otolaryngology Department, Washington
University School of Medicine, St. Louis, MO2.
Synucleins are a small family of proteins which comprise three isoforms: alpha-, beta-, and gamma-synucleins. Synucleins are found in many
tissues but are expressed primarily in nervous tissue. Synucleins are of strong research interest because of the role they may play in
neurodegenerative diseases, including Alzheimer’s, Parkinson’s, and dementia. Parkinson’s, for example, is associated with the abnormal
accumulation of alpha-synuclein. Synucleins are important for the normal hearing sensitivity of mice, and they respond to toxic environmental
stimuli (such as overexposure to noise) and aging by improperly aggregating or translocating from one cellular location to another. Despite
research efforts, the normal cellular function of synuclein remains hidden. One way of answering this question has been to find how synuclein
localizes in synuclein-expressing tissue. The goal of this research was to use electron microscopy to investigate the localization of synuclein
in auditory tissue and to thereby come closer to understanding the function of synuclein in hearing. To date, lighty microscopy studies have
revealed that alpha-synuclein localizes to synaptic terminals at the base of inner and outer hair cells and at synaptic terminals in the dorsal
cochlear nucleus; beta-synuclein localizes to spiral ganglion cells and synaptic terminals in the ventral cochlear nucleus; and gamma-synuclein
localizes to the cytoplasm of Dieter’s cells. Current efforts are focused on the ultrastructural confirmation of these findings using colloidal
gold immunolabeling of LR White embedded tissues and examination under the transmission electron microscope.
MYOSIN VI MAINTAINS ACTIN CONE STRUCTURE IN D. MELANOGASTER BY STABILIZING
BRANCH POINTS OF ACTIN FILAMENT MESHWORK
Andrew P. Stein1, Mamiko Isaji1, Deborah J. Frank1, Kathryn G. Miller1, Biology Department, Washington University, St. Louis, MO1.
Myosin VI is a member of a family of actin associated motor proteins, and it is expressed ubiquitously in eukaryotic cells where it is involved
with numerous processes including endocytosis, exocytosis, cell polarity and cell adhesion. However, the exact role it plays in these processes
remains unknown. In Drosophila melanogaster, myosin VI deficient males are sterile. Myosin VI localizes on the front of an actin structure
known as the actin cone that is involved in the individualization step of spermatogenesis. Actin cones consist of two domains: one is a network
of parallel actin bundles and the other is a meshwork of branched actin filaments located at the front of the cone. The Arp2/3 complex binds
to the side of pre-existing actin filaments and nucleates polymerization of new filaments to create the branched actin network. Additionally,
Arp2/3 complex has ATPase activity through its Arp2 subunit, and this allows it to detach from actin filaments. Previous data showed that
myosin VI has a role in maintaining the meshwork structure along with the Arp2/3 complex. Although we know that myosin VI stabilizes
actin cone structure, the mechanism it employs to stabilize the actin cones is unknown. Therefore, we wanted to determine how myosin VI
works to achieve this function. We hypothesized that myosin VI stabilizes the front of the actin cones by replacing the function of Arp2/3
complex at the branch points that form the actin meshwork. One mutation (H161A) in the Arp2 subunit has been shown to allow Arp2 to
remain bound to actin filaments for a longer period of time. In this mutant, actin filament depolymerization is delayed and the branch points
remain longer as compared to actin filaments in the presence of unmutated Arp2. If myosin VI does stabilize the branch points of actin
filaments, then this Arp2 mutant should rescue actin cone structure in myosin VI deficient flies. Our results show that flies with the Arp2H161A
mutant in myosin VI deficient background had larger actin cones that align more properly than flies without the Arp2H161A mutant;
however, the male flies were still sterile. Overall, these results suggest that Arp2H161A mutant could partially complement the function of
myosin VI, which stabilizes actin cone structur. Therefore, myosin VI might contribute to the stabilization of branch points in the actin
filament meshwork in a similar manner to the Arp2/3 complex.
THE DISTRIBUTION AND SPREAD OF AMPHIBIAN CHYTRID FUNGUS IN THE AMERICAN MIDWEST
Alex Strauss1, Jonathan Chase1, Kevin Smith1, Biology Department, Washington University, St. Louis, MO2.
The pathogenic amphibian chytrid fungus, Batrachochytrium dendrobatidis (Bd), is an emergent infectious disease which has recently led to
significant amphibian declines. Bd has caused extinctions in areas as geographically distant as Australia and Panama, and will continue to
pose a significant threat to global amphibian biodiversity in the future. Bd occurs in the American Midwest, but the way Bd moves across
landscapes and selectively infects certain areas is poorly understood. During the summer of 2009 we conducted a three-part observational
study of East-Central Missouri with three questions in mind: 1) What are the local rates of chytrid infection; 2) What is the spatial
distribution of infections; and 3) What environmental gradients can explain this distribution? The ultimate goal of this study is to construct
a model describing the spread of Bd based on its distribution along various biological and physical gradients. We present preliminary data
obtained through microscopic inspection of the mouthparts of gray tree frog tadpoles (Hyla versicolor). An average of nine Hyla tadpoles were
taken from each of eleven ponds (N=102) within a 120-mile radius of St. Louis. Subsequent data will obtained through quantitative
real-time PCR of mouthparts from the frog genus Rana (N=830).
50
THE ROLE OF VINCULIN IN NEURITE EXTENSION
Dharmesh Tank1, Cong Lucy Li2, Narendrakumar Ramanan2, Biology Department, Washington University, St. Louis, MO1; Department
of Anatomy and Neurobiology, Washington University School of Medicine, St. Louis, MO2.
One of the areas of focus in the Ramanan lab is in understanding the molecular mechanisms by which the transcription factor, Serum
Response Factor (SRF) regulates the growth of dendrites and axons in central nervous system neurons. The lab identified Glycogen Synthase
Kinase (GSK-3β) as an upstream activator of SRF-dependent transcription. Earlier studies have shown that GSK-3β is important for neuronal
polarity, dendrite growth, and axonal growth; however, the downstream transcriptional program mediating GSK-3β signaling in neurons was
not entirely known. To identify the downstream mediators of GSK-3β-SRF signaling, gene expression analysis was carried out using neocortex
from SRF knockout mice. Among several candidate genes identified from this screen, we initially focused on Vinculin (Vcl). Vcl is a
cytoskeletal protein located on the cytoplasmic side of focal adhesion sites and functions in tethering actin-cytoskeleton to these focal adhesion
sites. The importance of Vcl for neuronal development in vivo has never been addressed before as Vcl null mice exhibit early embryonic
lethality. To study the necessity of vinculin, we first knocked down Vcl using shRNA in hippocampal neurons and found that Vcl was
important for neurite outgrowth. In necessity experiments, we overexpressed Vcl in SRF knockout neurons and found that Vcl can partially
rescue the growth deficits of SRF-null neurons. Together, these experiments suggested that Vcl is an important mediator of neurite outgrowth
downstream of SRF signaling in neurons.
CIRCADIAN EXPRESSION OF CONNEXIN43 IN ASTROCYTES
Connie Tsai , Luciano Marpegan1, Erik Herzog1, Biology Department, Washington University, St. Louis MO1.
1
The mammalian suprachiasmatic nucleus (SCN), composed of neurons and astrocytes, coordinates daily rhythms in behavior and physiology.
The regulation of astroglial rhythms remains unclear. Because culture density affects the period, amplitude, and damping of circadian gene
expression in glia, we hypothesized astrocytes communicate circadian timing information to each other through non-diffusible signaling.
We examined the expression of connexin43 (Cx43), the dominant gap junction protein expressed in cultured astrocytes, and its role in
circadian timing.
Using immunolabeling, we found Cx43 in intracellular vesicles and the plasma membrane of astrocyte cultures and SCN and cortex
sections. Positive and negative controls showed the Cx43 antibody was specific. We performed Western blots to determine whether Cx43 is
circadian. Two weeks after plating astrocytes at high or low density, we exchanged the medium to reset the astrocytes’ circadian clock and
then harvested cultures every four hours for twenty-four hours. We measured Cx43 abundance as band intensity normalized to SyproRuby,
a total protein stain. We found that Cx43 concentration depended on time of day and culture density. These results are consistent with a role
for gap junctions in the coordination of daily rhythms among astrocytes and have implications for daily regulation of activity in the brain.
CHARACTERIZATION OF ORTHOLOGOUS CIS-REGULATORY SEQUENCES IN YEAST
Sandeep Venkataram1, Justin C. Fay2, Biology Department, Washington University, St. Louis, MO1; Department of Genetics,
Washington University School of Medicine, St. Louis, MO2.
The molecular evolution of cis-regulatory sequences is not well understood. Comparisons of closely related species show that cis-regulatory
sequences contain a large number of sites constrained by purifying selection. In contrast, comparisons of distantly related species show that
cis-regulatory sequences retain little to no sequence similarity but drive similar patterns of gene expression. Gain and loss of transcription
factor binding sites is one model by which cis-regulatory sequences can diverge without a change in function. Yet, because cis-regulatory
sequences are difficult to align between distantly related species, it is difficult to know whether sequence divergence is just a consequence of
binding site turnover. To characterize sequence divergence, we generated a database of orthologous cis-regulatory sequences across 14 yeast
species. Orthologous cis-regulatory sequences were defined by syntenic relationships with conserved flanking protein coding sequences. Both
local and global alignment algorithms show that nearly all orthologous cis-regulatory sequences have no significant level of sequence
similarity. Analysis of binding sites found by ChIP-chip, as well as well-annotated cis-regulatory sequences, show that a simple turnover
model cannot explain cis-regulatory sequence divergence. Our results indicate that cis-regulatory sequences may be evolving under a complex
model of compensatory changes or that many sequences have diverged in function.
51
ANALYSIS OF SYSTEMATIC BIASING OF AUDITORY FIELD RECEPTIVE FIELD CHARACTERIZATION
WITH BAND-PASSED NOISE
Edgar Y. Walker1 and Dennis L. Barbour1. Biomedical Engineering Department, Washington University, St. Louis, MO1.
Accurate identification of receptive fields of auditory neurons serves the critical role in characterizing and formulating models of the sound
processing schemes in auditory system for mammals. Traditionally, auditory neuronal receptive fields have been measured using pure tones.
However, neurons in lateral belts are known to respond poorly to pure tones at any frequency or level. Given this, band-passed noise has been
used in estimating the center frequency of receptive field. In this study, we evaluate the effect of utilizing band-passed noise in estimating
central frequency of the auditory receptive field. We do so by constructing computational models of auditory neurons, and subjecting the
neurons to sounds that have the same characteristics as real sounds used in the corresponding real physiology experiments. The model
indicates that using band-passed noise in estimation of central frequency results in systematic bias when applied to auditory nerves with
asymmetric receptive field. Furthermore, the model indicates that the phenomenon of bandwidth tuning may be explained as an artifact of
biased measurement of the central frequency. The use of band-passed noise in estimating central frequency therefore should be done with
more care and may even be discouraged.
DIFFUSION TENSOR IMAGING OF CIVILIAN TRAUMATIC BRAIN INJURY:
AN ADVANCED APPROACH TO CHARACTERIZING BRAIN INJURY
Kurt Wall1, David Brody, M.D./PhD, Department of Neurology, Washington University School of Medicine, St. Louis, MO2.
Traumatic Brain Injury (TBI) afflicts nearly 1.4 million people every year in the US alone, and leads to an estimated cost of $60 billion annually.
The four most prominent TBI pathologies are sub-arachnoid hemorrhage (SAH), diffuse axonal injury (DAI), hematoma, and contusion. While
the computed tomography (CT) scan has been well established as a valid technique in the detection of hemorrhage, contusion, and hematoma, it
remains relatively ineffective at detecting DAI. There are times when DAI is the only physiological trace of brain injury; thus, many brain injuries
go undetected or misdiagnosed when only examined with CT. Diffusion Tensor Imaging (DTI), has shown promise in remedying this problem.
DTI is an advanced MRI technique that measures the directional diffusion of water molecules. The diffusion tensor signal is based on the
anisotropy (3-dimensional asymmetry) of water diffusion. In healthy brain tissue, water diffusion is highly restricted in white matter, leading
to a high relative anisotropy (RA) value. In diseased or damaged brain tissue, barriers to diffusion may be removed or weakened, causing a
lower anisotropy at that specific location. If validated, DTI may be applied to the management of TBI in three distinct ways: first, it may
prove useful in the detection of injury pathologies that are problematic for CT and conventional MRI, such as diffuse axonal injury. Second,
it may serve as a predictor of functional outcome for TBI patients. And third, it may prove useful in forming a new classification scheme for
TBI patients, aiding in triage decisions.
To test the validity of DTI in detecting traumatic brain injury, we examined 18 subjects with documented TBI and known cognitive
deficits, as well as 12 age-matched controls. DTI scans, as well as a battery of other conventional MRI images, were acquired on these
patients. The primary hypothesis of the study is that DTI will correlate to neurological deficits more accurately than CT or conventional
MRI. Relative anisotropy was observed to be significantly decreased for the TBI group in the genu, splenium, and body of the corpus
callosum and the left and right cingulum bundles in this preliminary data set. Our findings support the notion that DTI is a valid biomarker
of traumatic brain injury among the civilian population.
QSEBC SIGNALING AND UROPATHOGENESIS: IDENTIFYING SIGNALS FOR QSEC AND STUDYING
THE EFFECTS OF CUP OPERON DELETIONS AND FIMA MUTATIONS IN UROPATHOGENIC E. COLI
Charles Wang1, Dr. Scott Hulgren2, Biology Department, Washington University, St. Louis, MO1; Department of Molecular
Microbiology, Washington University School of Medicine, St. Louis, MO2.
Urinary tract infection (UTI) is the second most common type of infection, affecting millions of people each year. Uropathogenic Escherichia
coli (UPEC) is responsible for 90% of UTIs. Once it enters the urinary tract, UPEC is able to attach itself to the bladder epithelium, invade
host cells and form intracellular bacterial communities (IBCs). IBCs protect the bacteria from the host’s immune system and antibiotics,
allowing the bacteria to persist in the bladder and cause recurrent infections. The signaling mechanisms behind these events, however, are
not well understood.
QseBC, a regulatory system found in the UPEC strain UTI89, has been shown to regulate UPEC virulence factors. It has been established
that in UTI89, deleting qseC, the gene encoding the sensor kinase QseC, affects transcription of multiple chaperone-usher pathway (CUP)
operons, at least one of which – fim, which encodes the proteins necessary to construct type 1 pili – is known to be a critical factor in
uropathogenesis. Currently, the signals for QseC in UPEC are not known, nor are the roles of many of these CUP operons. Moreover, the
complete role of the major subunit in type 1 pili – FimA – is also not clear. Over the summer, I tested possible signals for QseC in UTI89
and the effects of deleting CUP operons whose transcription is affected by qseC deletion. I also screened possible systems to use in investigations
of the effects of mutations in FimA.
52
The preliminary data show that in UTI89, QseC responds to epinephrine, though the epinephrine antagonist phentolamine has no effect
on QseC’s ability to detect epinephrine. Deletions of several CUP operons showed no effects in functional assays. Lastly, the systems screened
for investigating FimA mutations have proven to be somewhat adequate, but not perfect. Further investigation is needed on all three fronts;
more signals for QseC need to be identified, additional CUP operon deletions tested, and the effect of FimA mutations studied when an
appropriate system is identified.
EFFECTS OF INVASIVE PLANT LONICERA MAACKII ON AMPHIBIAN LARVAE
Kai Wang1, James Watling1, John Orrock1, Biology Department, Washington University, St. Louis, MO1.
Lonicera maackii is a widespread invasive species in much of the eastern and central United States, and may have detrimental effects on local
ecosystems. Amphibians are going extinct faster than any other terrestrial vertebrate taxa, and invasive species are an important threat to
terrestrial biodiversity. This study investigated the effect of L, maackii extracts on the aquatic life stage of amphibians. To do the study, three
extracts were made: Blank (dechlorinated tap water), Native (leaf litter from a mixture of native species), and Lonicera (leaves of L. maackii).
Individual tadpoles of four species, Bufo americanus, Hyla chrysoscelis/versicolor, Rana blairi, and Ambystoma maculatum, were placed into each
bucket, and the number of living tadpoles was recorded three times per week for 45 days. Digital photographs were taken on day 30 of the
experiment, and body length was measured from photographs.
The results showed no differences in body size across treatments for any of the species. There was, however, a strong response of survival
for B. americanus. Approximately 50% of B. americanus individuals die within 72 hours of being placed in extracts. This evidence suggests
that some compounds of the L. maackii leaves must be toxic to some species of amphibian larvae.
SIMULATIONS OF DIFFUSION AND CALCULATIONS OF LONGITUDINAL AND TRANSVERSE DIFFUSION
IN BRANCHING TUBE STRUCTURES
1
1,2
Michael Wang , Mark S. Conradi , Dmitriy Yablonskiy2, Alex Sukstanskyy2, Physics Department, Washington University,
St. Louis, MO1; Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO2.
The helium-3 MR group of Washington University’s School of Medicine has recently proposed a theory for understanding gas diffusion within
the acinar airways. The model makes the mathematically simplifying assumption of infinite-length acinar airways. The model has been
partially validated by comparisons to morphometric measures of fixed tissue and to X-ray CT density.
This computer simulation project tests the effect of the finite airway lengths, the weakest assumption in the theory, using C++. Particles
move within a lattice of connected tubes by random walk. In the first type of simulations, the tubes from a 3D “jungle-gym,” with branching
points joining the tubes running along x, y, and z. In the second type, the tubes were generated with morphological bifurcation angles. The
simulated signal decay data is analyzed in the same manner as the experimental diffusion NMR data. For both tube systems, the model
returned physiologically supported values for diffusion in the limit of very long tubes. As the tube dimensions neared morphological values,
the model still fit the data very well, but the values for longitudinal diffusion range beyond physiologically expected values. Future simulations
will test the model with more lung-like tube systems.
BENEFICIAL EFFECT OF EXENATIDE ON GLUCOSE HOMEOSTASIS AND SURVIVAL IN
RIONAVIR-TREATED MICE WITH ADVANCED DILATED CARDIOMYOPATHY
1
Dennis Woo , Arpita Kalla Vyas2 Kai-Chien Yang2 Patrick Y. Jay2 Paul W. Hruz2, Pediatric Department, Washington University School of
Medicine, St. Louis, MO2.
Ritonavir and other first generation HIV protease inhibitors are known to contribute to the development of insulin resistance and other metabolic
changes that increase the risk for cardiac disease. Subclinical diastolic dysfunction is highly prevalent in HIV infected patients with features of the
metabolic syndrome. Previous work in murine models has shown that blockade of glucose transport by ritonavir produces acute decompensated
heart failure in a murine model (TG9) of dilated cardiomyopathy. Since cardiac function and survival are correlated with changes in myocardial
glucose uptake, we investigated whether improved glucose uptake would prevent the adverse effects of ritonavir in this heart failure model.
To examine the relationship between ritonavir-induced insulin resistance and survival during advanced dilated cardiomyopathy, exenatide,
captopril, or vehicle was administered continuously to TG9 mice starting at 56 days of age and ritonavir or vehicle was administered daily
starting at 75 days of age. Glucose homeostasis was assessed using intraperitoneal glucose tolerance testing and tissue 2-deoxyglucose uptake.
Ritonavir administration exacerbated elevated fasting and post-prandial blood glucose levels in TG9 mice while exenetide improved both
glucose tolerance and myocardial 2-deoxyglucose uptake over vehicle-treated mice. Survival was improved in exenetide-treated mice (89.6 +
2 days) over vehicle-treated mice (83.0+0.6 days) while myocardial GLUT4 and GLUT1 levels were not different between groups. Captopril,
an ACE inhibitor, improved survival (86 +- 1.3 days) while diminishing the detrimental effects of ritonavir treated mice. Ritonavir/exenatide
53
mice improved survival (83.0+0.8 days) over ritonavir/vehicle mice (78.4 + 3.1 days) while ritonavir/captopril (81.2 + 3.1 days) did not.
Exenatide improves system and myocardial-specific glucose uptake and diminishes the detrimental effects of ritonavir on cardiac function
and survival during advanced dilated cardiomyopathy. These data provide a rationale for studying the influence of impaired glucose
homeostasis on cardiac function in HIV-infected patients treated with protease inhibitors and suggest that efforts to improve glucose
disposal would be beneficial in preserving cardiac function.
THE EFFECT OF VOLUNTARY EXERCISE ON DENSITY OF DOPAMINE RECEPTORS IN MOUSE STRIATUM
AND SIGMA-2 RECEPTORS IN MOUSE HIPPOCAMPUS
Hannah Wroblewski1, Jinbin Xu2, Lynne Jones2, Robert Mach2, Physics Department, Washington University, St. Louis, MO1; Radiology
Department, Washington University School of Medicine, St. Louis, MO2.
Voluntary running in mice has been shown to increase hippocampal neurogenesis and has been investigated for its effect on depression-like
behavior. Both dopamine and sigma receptors have been shown to play a role in depression regulation and neurological diseases. The effects
of exercise on dopaminergetic systems are not yet understood. We examined D1, D2, and D3 receptor density in the mouse striatum and
sigma-2 receptor density in the mouse hippocampus after voluntary running on wheels for two weeks. Our data show decreases in D1, D2,
D3, and sigma-2 receptor density in running mice, though only significant for the D3 receptors. Voluntary exercise may be a key to reducing
D3 receptor density without drug treatment.
TRACER VALIDATION OF CFT AS POTENTIAL MARKER FOR NIGROSTRIATAL NEURONS
Chen Xu1, Dr. Joel S. Perlmutter2, Biology Department, Washington University, St. Louis, MO1; Department of Neurology,
Washington University School of Medicine, St. Louis, MO2.
Parkinson’s disease (PD) is one of the most debilitating neurological disorders encountered. Individuals afflicted with this disorder experience,
among other symptoms, tremor, rigidity, bradykinesia, and postural instability [Selby]. These behavioral manifestations of PD can be induced
in non-human primates by injection of the selective neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). MPTP selectively
destroys dopamine-producing nigrostriatal neurons leading to loss of striatal dopamine, mimicking the loss of nigrostriatal
neurons and striatal dopamine deficiency that occur in people with PD.
The goal of this project is to validate a neuroimaging marker for the loss of nigrostriatal neurons. Dopamine transporters (DAT)
located on nigrostriatal neuron terminals in the striatum transport dopamine from the synapse back into the pre-synaptic neuron.
[11C] 2betacarbomethoxy-3beta-4-fluorophenyltropane (CFT) is a synthesized radioligand that binds selectively to these DAT transporters.
It is hypothesized that reduction of the selective uptake of CFT in the striatum will reflect the loss of dopaminergic projections. This
hypothesis will be tested by calculating a binding potential (BP) of CFT in non-human primates given different doses of MPTP to
determine the relationship between reduced striatal CFT BP with both validated measures of animal behavior and striatal dopamine content
measured using high pressure liquid chromatography (HPLC). Statistical analysis of CFT BP with striatal dopamine content showed significant
strong positive correlations. Significant correlations between CFT BP and animal behavior measures were revealed as well.
DEVELOPMENT OF AN IMAGE GUIDED MICRO IRRADIATOR TO INVESTIGATE
RADIATION INDUCED CHANGES IN TUMOR VASCULATURE
Cong Yu1, Jordan Birch1, Bethany Kassebaum2, Daniel Low2, and Enrique Izaguirre2, Biology Department, Washington University,
St. Louis, MO1, Department of Radiation Oncology, Washington University School of Medicine, St. Louis, MO2.
We are constructing a small animal image guided micro radiation therapy instrument (microIGRT), which includes a micro radiation therapy
(microRT) subsystem integrated with an on board micro computed tomography (microCT) subsystem. The microRT consists of an
orthovoltage x-ray source to accurately deliver a highly conformal dose distribution onto a target tumor.
The microCT was specially designed and constructed using a 70x70 um focal spot x-ray source, which is mounted on a high resolution
rotating gantry. The microCT detector, an amorphous flat panel silicon detector, has an active area of 13x13 cm2 and a pixel matrix of 10242
pixels. The source and detector are mounted on linear translation stages (radial motion) for a fine control of the image resolution and the field of
view. This high resolution microCT will allow our group to image with high detail the tumor microenvironment during fractionated treatments.
The reconstructed images of the tumor vasculature will be used to determine the distribution of blood in vascular tumors and to estimate
the oxygen and nutrients supplied by the tumor vasculature to tumor cells. Reconstructed images taken during different stages of the treatment
will be used to establish patterns of vascular normalization induced by ionizing irradiation.
END OF SUMMER UNDERGRADUATE RESEARCH FELLOWSHIP (SURF) PRESENTATIONS
54
CAREER CENTER INTERNSHIP PRESENTATIONS
Presenters are listed alphabetically by last name.
Caroline Andler
Hallie Applebaum
Brittany Beasley
Jacob Bernstein
Philip Bolson
Christine Borosh
Kayla Brinkley
Frank Bruno
Kuan Butts
Shelby Carpenter
Haley Clegg
Fernando Cutz
Daniel DuGoff
Ross Festenstein
Lauren Finkelstein
Colin Foley
Kaitlin Freedman
Alexander Garcini
Christopher Geiger
Kevin Greenlee
Alice Gu
Nil Gural
Raina Hall
Amy Heard
Jessie Hu
Emily Jacobson
Molly Jennings
Stephen Johnson
Michelle Ju
Preethi Kembaiyan
Laura Lane-Steele
Jeremy Laub
Sarah Lavin
Alan Liu
Jordan Livingston
Cynthia Mancha
Laura Mart
Kaitlin McFadden
Elizabeth Merrill
Tobacco Use Prevention Program
Research Assistant for Professor Peter Benson, Public Health Professor at
Washington University
Pace University
The Family Business Consulting Group
Pacific Northwest Economic Region
Spring Creek Farm
River Styx Literary Magazine
Finley LLC
Lim Design Group, Inc.
Personal Rights of Missourians (PROMO)
InStyle Magazine
Broward County Public Defender’s Office
Peter Som, Inc.
Rawlings; Skybox Sports Bar & Grill; Taste of St. Louis
Africa Action
Washington University iGEM
New York Mayors Office to Combat Domestic Violence
Saint Louis Zoological Park
Washington University in St. Louis School of Medicine
Moving Off Campus
The Women’s Safe House
Stanford Hospital Blood Center
St. Louis Crisis Nursery
Senator Mary Landrieu
St. Louis Crisis Nursery
Discovering Justics
St. Louis Art Museum
International Business Government-Counsellors, Inc.
Center for Advanced Medicine, Radiation Oncology Department
Uganda Development & Health Associates
Department of Health and Environmental Control
Crane Merchandising Systems
Derech Hateva
Leggett and Platt, Inc.
Pittsburg Mind/Body Center
Cold War History Research Center
Shakespeare Santa Cruz
Sierra Club, Illinois Chapter
Social Development Resource Center
55
CAREER CENTER INTERNSHIP PRESENTATIONS
Presenters are listed alphabetically by last name.
David Messenger
Alex Molinari
Benjamin Murphy
Akhila Narla
Shen Ni
Genevieve Otto
Katharine Owens
Emily Pittman-Swint
Alexa Polokoff
Marion Pope
Hillary Price
Ernika Quimby
Chethan Rao
Gilian Rappaport
John Richter
Jordan Roberts
James Ross
Kamryn Schalker
Eleanor Scholes
Ilana Schwartz
Anne Seibert
Cari Sekendur
Benjamin Shanken
Lucy Shen
Toby Shepard
Julie Shore
Gabriel Slavitt
Kathryn Sparks
Stephanie Spence
Thomas Stevens
Gabrielle Surick
Erin Thimmesch
Michele Tsai
Eliot Walker
Celso White
Angelique Williamson
Michaela Wilson
Kyle Wu
Molly Wyler
National Archives-Center for Legislative Archives
Orthopaedic Cell Biology Laboratory at University of Iowa
Welte Institution for Oaxacan Studies
Uganda Development & Health Associates
Cohen Architecture Company
International Institute of St. louis
Sotheby’s
Iracami Atlantic Reainforest Reserve and Conservation Center
Explore St. Louis; St. Louis Convention & Visitors Commission
Viva Nicaragua!
LiveFeed
Small Rain, Inc.
Washington University in St. Louis School of Medicine
AIR Gallery
Arkansas Sierra Club and Arkansas Education Television Network
International Business Internship Exchange
Vattikuti Urology Institute at Henry Ford Hospital
Meds & Foods For Kids
Nbreckenridge Outdoor Education Center
Anti-Defamation League
Institute for Progressive Leadership
Category unknown
Rio de la Plata
Moving Off Campus
US Department of State- Foreign Service Institute
KSHX 88.1
Eric Troffkin
United States Department of State, Bureau of East Asian Affairs, DPRK Unit
Beyond Housing
International Genetically Engineered Machines Research Competition
St. Lukes - Roosevelt Hospital Center
Lawrence Memorial Hospital
Queen of Peace Center (a part of Catholic Charities)
Washington University in St. Louis Media and Machines Lab
Bad Boy Entertainment
YWCA Nashville
Partners for Just Trade
The Charest Laboratory - Tufts Medical Center
Missouri State Public Defender System
56
STUDENTS AND TEACHERS AS RESEARCH SCIENTISTS (STARS) PRESENTATIONS
Presenters are listed alphabetically by last name.
PRESENTERS
MENTORS
Sofia Aronson
Sergey Korolev
MICDS
Saint Louis University
Modulation of RecO DNA Annealing and Binding Properties by RecR from Escherichia coli and Deinocuccus radiodurans
Matt Benson
Shelley Minteer
Mascoutah Community High School
Saint Louis University
Immobilizing Capacity of Bilirubin Oxidase in Nafion® Polymers in an Air Breathable Biocathode
David Bruns-Smith
Richard Mabbs
Ladue Horton Watkins High School
Washington University
Saturation Effects in Microchannel Plate Detectors in the Photodetachment of Iodine Ion
Phillip Hsu
Richard Ostlund & Chaya Gopalan
Marquette High School
Washington University
Role of Sodium-Dependent Myo-Inositol Transporter 2 Protein in the Transfer of Inositols
Sarah Huynh
Daniel Giammar
Affton High School
Washington University
The Effects of pH and Free Chlorine on the Solubility of Platternerite (PbO2)
Ravi Kasinadhuni
Wendi Neckameyer
Marquette High School
Saint Louis University
Dopamine Receptors in Drosophila melanogaster in Relation to Stressors
Rishub Keelara
Paul Schlesinger
MICDS
Washington University
Pore Forming Activity of Mutant Forms of Bax: Full Length Wild Type Bax and Mutant C62A, C126A
Kunal Mathur
Vijay Sharma
Marquette High School
Washington University
Novel Peptidomimetics for Probing Mitochondrial Membrane Potential within Human Epidermal Carcinoma Cells
Ali Sehizadeh
J. Gail Neely
Clayton High School
Washington University
Advancing the Methods of Measuring the Degree of Laterality in Human Facial Expressions
Monica Sharma
Phyllis Stein
Eureka High School
Washington University
Association of Information from Heart Rate Patterns on Holter Recordings and Sudden Cardiac Death in the Elderly
Shaun Vaidyan
Dorota Skowyra
Ladue Horton Watkins High School
Saint Louis University
Factors Affecting the Accumulation and Degradation of GFP-Reporter Proteins
Casie Wang
Vijay Sharma
Marquette High School
Washington University
Design and Validation of Radiolabeled and Fluorescent Peptides as Probes of Mitochondrial Membrane Potential
57
PRESENTERS’ ACKNOWLEDGEMENTS
Haejun Ahn — I would like to thank the
HHMI/SURF and the Office of Undergraduate
Research for the opportunity to present my work and
the True lab for all the support and guidance provided,
especially Dr. Heather True and mentor Adeline Lin.
Ben Alexander — Specimens for TEM-EELS
nanocharacterization were prepared by H. Wynder in
the Histology and Microscopy Core Facility of the
Washington University School of Medicine. The
authors thank Lucas Palisin for assistance with tissue
fixation techniques.
Kalee Cassady — Thank you to Dr. Lo for all her
continued support and guidance.
Graham Caulkins — I would like to thank
Dr. Kenneth Olsen for this opportunity. I would also
like to thank Nicholas Kooyers for his invaluable
guidance and support. Lastly, I would like to thank
Linda Small and the entire Olsen lab for their feedback
and assistance.
Samir Chabra — This project was supported by a
Cameron Ball — I would like to thank my mentor
Dr. Robert P. Mecham for his support and feedback.
Summer Undergraduate Research Fellowship funded
by a grant from the Howard Hughes Medical Institute
and the Imaging Sciences Pathways grant. I would also
like to thank Scott Burns and Dr. Barbour
Hunter Banks — I would like to thank Professor
Stephanie Chang — I would like to thank
Schilling and his students Wenli Bi and Narelle Hillier
for all of their help and advice since I have been in
their lab.
Dr. Bob Blankenship, Dr. Yinjie Tang, Barb Honchak,
Aaron Collins, and Dr. Joseph Tang, among others, for
providing us with invaluable guidance and resources
throughout the summer. Special thanks also to the
entire iGEM team, and especially to Jacob.
Lurit Bepo — I would like to offer my gratitude to:
Dr. Carolyn Sargent, Dr. Gerald Early, Dr. Joseph
Thompson, Dean Mary Laurita, and Olivia Harman
for all their guidance, mentorship, and assistance in the
research process thus far.
Chloe Bethany — Chloe Bethany would like to
thank Niki Miller and Peter Hoch for a generous
introduction into the endless curiosities of Botany, and
for many kind words along the way.
Adithya Bhat — Mingfeng Bai, Jinda Fan,
Kexian Liang, and Samuel Achilefu, the Radiology
Department at Washington University Medical School
Rani Bhatia — I would like to thank my mentor,
Dr. Laura Piccio, for her sincerity and patience with
me this summer. She was actively involved in my
experience even while juggling ten other things and
always made my success her own. I would also like to
thank my PI, Dr. Anne Cross, who has become a large
source of inspiration for me.
Naitik Bhatt — We would like to thank Dr. Arye
Nehorai and the ESE Department; Project Supervisor,
Joshua York (BSEE ‘09); and NREL Scientists,
George Scott and David Corbus, for making this
research possible.
Jordan Birch — I would like to thank my family
first for being a great resource and support for me.
Also I truly appreciate all the support and learning I
have gained while working on this project. Enrique
Izaguirre my hands on mentor was very helpful with me
in the lab and helped me learn an incredible amount.
Steven Borson — I wish to thank Namiko Abe for
all her guidance and instrumental help in my project.
Rachel Bowling — I would like to thank
Dr. Gereau for the opportunity and the entire lab for
their support and guidance. Thanks especially to Ben
Kolber, PhD, who served as my research mentor and
guided me closely throughout the experience. I am
indebted to my parents for their ceaseless support and
encouragement.
Stephanie Brewer — I’m extremely grateful to
Dr. Mike Strube for his valuable guidance and insight,
Kristin Sobotka and the Office of Undergraduate
Research for their support, each student who
contributed as a participant in this study, and Wash U
Psychology for helping me discover my passion for this
research.
Joy Chiang — I would like to show my appreciation
for Dr. Arye Nehorai, Patricio S. La Rosa, Vanessa
Tidwell, Ed Richter and the EE office.
Yan Yi Anny Chung — I thank Jennifer Hopwood
and Mike Arduser for tremendous help with species
identification. Thanks also to JP Gorham, and students
of the TERF program for assistance in field work. The
staff and community at Tyson Research Center provided
a supportive research environment that is greatly
appreciated.
Caitlyn Clarke — I would like to thank the
Academic Directors of the School for International
Training (SIT), Dr. Earl Noelte, Dr. Alexandre
Lambert, and Dr. Gyula Csurgai for guiding me in my
research and providing constructive feedback. Thanks
also to Ms. Aline Ammann and Anne Borrel of SIT.
Michael Craig — I would like to thank the National
Science Foundation for funding, and Drs. Lars
Brudvig, John Orrock, and Ellen Damschen for
guidance and advice.
Jamie Cummings — Professional contacts:
Dr. Robin Shepard, Melanie Osborn, and Sal
Ghodbane, Engineers Without Borders members Cory
Flanigan, Jamie VanArtsdalen and Monatrice Lam.
Geoffrey Dang-Vu — I would like to thank
Dr. John Battaile, Dr. Derek Byers, and Dr. Michael
Holtzman for their invaluable guidance and support
throughout my project.
Erika Deal — I would like to thank Lynne Tatlock
for her generous support and encouragement; without
her help, the inception and development of this project
would not have occurred. I would also like to thank
Professor Loewenstein and the other professors of IPH
who have been so enthusiastic in their support.
Lisa Deng — Asis Khan, Keliang Tang, L. David
Sibley, Washington University Summer Undergraduate
Research Fellowship, Howard Hughes Medical Institute
Jarod DuVall — Dr. John A. Cooper, Dr. Meng-Chi
Lin, Dr. Brian J. Galletta, The Cooper Lab at the
Washington University in St. Louis School of
Medicine, The Washington University in St. Louis
Biology Department, The Summer Undergraduate
Research Fellowship Program
Aerospace Systems Lab, University Nanosat Program
Sarah Ebstein — I would like to thank Martha
Bhattacharya, Aaron DiAntonio, and the rest of the
DiAntonio lab.
David Case — The author wishes to thank Daniel
Giammar for his advice and encouragement, as well as
the Aquatic Chemistry Laboratory for their support in
executing these experiments.
Michelle Eisenberg — I would like to thank
Dr. Jeff Zacks for advising my project and Dr. Chris
Kurby, Nayiri Haroutunian, Sylvia Lee, and Albert
Deng for their work on the study.
Kaitlin Burlingame — Dr. Michael Swartwout,
58
Victor Ekuta — I would like to thank Dr. Alexander
Schier for allowing me to intern in his lab during the
summer, Dr. David Schoppik for guiding me throughout the project process, Andre Green for providing
suggestions on the development of the poster, and Tom
Torello, Victoria D’Souza, and Michael Lawrence.
Adam Eltorai — I would like to thank David
Holtzman, Jungsu Kim, Hong Jiang, Floy Stewart, and
Seonha Park.
Mark Fahey — Dr. Ivy Jong Dr. Karen O’Malley
Paul Fahey — I want to thank the Summer
Undergraduate Research Fellowship for this opportunity,
as well as the O’Malley Lab, in particular my mentor
Karen O’Malley and my bench mentor Vikas Kumar.
Martin Fan — I would like to thank Dr. Tianbing
Xia, Dr. Liang Zhao, Dr. Beena Kadakkuzha, Sangwon
Lee, Kyle Yen, and Hannah Stringfellow for their
support through this project. I wish to extend special
recognition to Niyati Jain for consistently going far out
of her way to ensure that this project succeeded.
Nathan Fine — Dr. Lo guides me masterfully
through the research process, yet still gives me the freedom to make mistakes. Thank you for making this a
very rewarding and enlightening experience so far.
Darren Finkelstein — I would like to thank
Dr. Liviu Mirica, Howard Hughes Medical Institute,
SURF Program, and the Washington University
Chemistry Department for giving me the opportunity
to participate in original and captivating research.
Kevin Gao — I am sincerely grateful to Dr. Chalker
and all of the graduate students, technicians, and
fellow undergraduates that made my research
experience fun and possible. I thank the Howard
Hughes Medical Institute and the National Science
foundation for financial support.
Jacob Greenberg — I would like to thank
Dr. Yehuda Ben-Shahar for all of his support and
guidance throughout this project.
Elyse Hanly — I would like to thank the members
of the Newberry Lab at Washington University School
of Medicine, those involved with the SURF program
at Washington University in St. Louis, as well as
NIH/NIDDK and CCFA.
Patrick Hanly — I would like to thank Jon Chase
and Kevin Smith for their endless support and advice,
as well as all of the Tyson Research Center’s staff and
students.
Kimberly Hartstein — I would like to thank the
organizers of the National Science Foundation
Summer Research Program in Solid State and
Materials Chemistry for giving me this summer
research opportunity, as well as Dr. Sophia Hayes and
Sarah Mattler for their guidance and support.
Robert Harvey — I want to thank all of the
individuals who took time out of their extremely busy
lives to discuss my research.
Mojibade Hassan — I would like the thank my
advisor Carolyn Herman and Kathryn Miller for
informing me about the HHMI EXROP program. I
would like to thank my mentors Ronald Evans and
Johan Jonker for allowing me to work in the lab and
giving me such great research experience.
Nicholas Hawco — I would like to acknowledge
Dr. Liviu M Mirica, The Mirica Group, The Office of
Undergraduate Research, The Howard Hughes Medical
Institute, and my family for their overwhelming support.
Aaron Hecht — Thank you to Khushbu Patel,
Ken Cadwell, Monica Walker and Clara Moon.
PRESENTERS’ ACKNOWLEDGEMENTS
Elizabeth Held — I would like to thank my research
Yedda Li — We would like to thank Bill Eades,
mentor, Dr. Tamara Doering, and all of the members
of the Doering Laboratory.
Jackie Hughes, and Christopher Holley at the Siteman
Cancer Center High Speed Cell Sorter Core.
Nicole Henniger — Kevin J. Black, M.D. Jonathan
Koller, BSBME, BSEE Miranda Lindburg Jeffrey M.
Zacks, Ph.D., and the rest of the C-SURE team
Sydnie Lieb — I would like to thank Dr. Benjamin
Kumfer, Dr. Scott Skeen, and Professor Richard
Axelbaum for their willingness to teach me and for
their incredible guidance during the course of these
experiments.
Michal Hyrc — I would like to thank Dr. Sophia
Hayes for allowing me to research in her lab and
advising me throughout the research process, Katie
Wentz for her input to the model and Erika Sesti,
Dustin Wheeler, Sarah Mattler, Kimberly Hartstein
and P. J. Morrison for their support.
Sirui Jiang — Special thanks to Dr. Robert Baloh
and Albert Misko for providing me with the
opportunity of doing such exciting research.
Erin Kane — Thank you to the St. Louis Zoo,
Dr. Sussman, Marc Fourrier, and Joshua Marshack for
their help with this project.
Andrew Kanyer — Washington University LEXAS
research group W. Robert Binns Martin H. Israel
Laura Kelly — I would like to thank Dr. Brett
Kessler, Dr. Itai Sened, Alana Bame and Gary Hirsch
for their support in my project.
Zachary Knudsen — Professor Arye Nehorai, Ed
Richter, Patricio S. La Rosa, Phani Chavali, Joshua
York ,Chase Lafont, Raphael Schwartz, Washington
University’s Electrical and Systems Engineering
Department, Matt Meshulam, Brian Blosser.
Joanna Kovalski — I would like to thank Sunday
Oladipupo for his direct guidance and support
throughout my research. I want to also thank Andrea
Santeford for her assistance in technique training and
troubleshooting. Finally, I would like to thank Dr.
Jeffrey Arbeit for providing overall project direction.
Natalie Kress — We would like to thank Matt
Thimgan, Paul Shaw, and the members of the Shaw
lab for their mentorship and guidance.
Rebecca Krock — I would like to thank the Herzog
lab for their support.
Anupam Kumar — I would like to thank
Dr. Shanti Parikh, the staff at Iganga Development
Activities and AIDS Concern (IDAAC), and the
Undergraduate Research Office for their support
throughout my work.
Alina Kutsenko — Dr. Gerald Dorn, Scot
Matkovich, and the rest of the Dorn Laboratory.
Ross Ladau — I would like to thank Nicholas
Mauro for guiding me over the summer and Victor
Wessels for providing the knowledge and instructions
for the analysis.
Charles LaFont — I really truly appreciate the entire
support of the Department of Electrical and Systems
Engineering at Washington University in St. Louis.
Specifically, Dr. Nehorai, Patricio La Rosa, Ed Richter,
Phani Chavali, Josh York, Raphael Schwartz, and Zach
Knudsen. Thank you for your support and guidance.
Emily Lebsack — Tom Bernatowicz, Ernst Zinner,
Kevin Croat, Frank Gyngar, Tim Smolar.
Eric Lee — Thanks to my mentors in the ecology
department- James Watling, John Orrock and Caleb
Hickman.
Lilly Leyh — I would like to thank Professor
Gustafson for his guidance during my project, and
Mujeres Creando for supporting me through my
research while in La Paz, Bolivia.
Franck Lin — Samuel Achilefu, Mikhail Y. Berezin,
Kevin Guo, Jeff Anderson, Kexian Liang, Mingfeng
Bai, Jei Zheng, Jinda Fan.
Miranda Lindburg — Thank you to Dr. Black, the
entire Black lab, Dr. Barnes and Dr. Church, and the
C-SURE program and fellows.
Evan Lobell — I would like to thank Peter Kastor
and Kristin Sobotka for their help and support.
Jessica Loyet — I would like to thank Dr. Peters for
teaching me and being patient with me as I learned
how to do this project. I would also like to thank
Loren Ahaus for all the help he gave me while learning
to use MATLAB.
Nathaniel Markman — I greatly appreciate those
who offered their support; the cabuyeros of Pucara,
Latin Flor, Peter Shear, Moraima Mera, and my
advisor, Rainer Bussman.
Sylvester Marshall III — I would like to thank my
research mentor Yu-Qing Cao, whose generosity and
guidance helped make this research experience a success. I would also like to thank Ping Liu, who was
always there for me when I had questions.
Bridgette Martinak — A warm thanks is extended
to the Maurer group, and especially Natalie LaFranzo,
for their excellent advice and continuing support.
Ryan Matos — I would like to thank Dr. YoungShin Jun, the Sigma Xi Chemistry Honorary Society
St. Louis chapter, I-CARES, the Consortium of Clean
Coal Utilization, and Dr. Yee Soong at the NETL.
Brian Mau — I wish to thank Dr. Vogel and Dr.
Jeong for their guidance and supervision of my project.
I would also like to thank Molly Sutherland and
Rebecca Oh for their support and guidance in the lab.
Dylan McLaughlin — Allan Doctor, MD; Stephen
Rogers, PhD; Tara Neumayr, MD; Lara Miller-Smith,
MD; Julie Kanter, MD; Daniella Corcuera; Jerlinda
Ross; Maggie Reagan; Krupali Patel; Lindsey Gibbons;
Tracey Erdman.
Christopher Menard — LANL: Scott Wilburn,
Americo Salas-Bacci, Aaron Couture, Andi Klein UK:
Christopher Crawford, Elise Martin, Roel Flores
UNAM: Libertad Barron-Palos, Quiela Curiel, Daniel
Marín Lámbarri, Penelope Rodríguez, Miguel Juárez
Hamilton College: Gordon Jones ORNL: Seppo
Pentilla NIST: Tom Gentile
Alice Meng — I would like to thank Dr. Blankenship
and his lab for their help, Sigma Aldrich for their generous donation of supplies, the McKelvey Scholarship
program, and everybody in the Washington University
iGEM team for their hard work.
Jonathan Millis — Lee Benham, Andrew Sobel.
Joshua Morris — Leonard Green, Joel Myerson,
Amanda Calvert, Kristin Sobotka, the OUR, the
Psychology Department
Ruth Nan — I would like to thank Peter Madzelan
for his guidance and mentoring. I would like to thank
my professor, Dr. Mark Wilson, for advising me on my
project. I would like to thank the University of
Nebraska - Lincoln for offering me this opportunity to
perform research this summer.
59
Akhila Narla — I deeply thank: my Writing 1
Instructor, Melinda Mahr, for her patient guidance,
encouragement, and edits, my Writing I class for providing feedback and support, the Writing 1 Office for
reviewing and giving me this opportunity to present, and
Professor Peter Benson for research abstract guidance.
Landon Oetjen — Special thanks to Dr. Dong Qin,
Dr. Yujie Xiong, Sarah Canniff, Amy Sears, Brent
Riggs, and Kristy Wendt
Neil O’Kelly — I would like to thank CHADS
Coalition for Mental Health for supporting my project
financially. I would also like to thank everyone in the
lab for all their help and training, especially
Dr. Botteron, Joe, and Tom.
Birce Onal — I would like to thank Dr. David
Reichert, Dr. Paul Kenis, Dr. Dexing Zeng, Dr. Tobias
Wheeler, and Dr. Amit Desai for their involvement in
this investigation.
Chiamaka Onwuzurike — I would like to thank
Erik Herzog, Christian Beaule, Louis Muglia, and
Benedict Kolber for their support, mentorship, and
guidance.
Mitch Otu — Dr. Kelle Moley Lauren Flessner The
Entire Moley Lab and Joan Riley Howard Hughes
Medical Institute Office of Undergraduate Research
Dustin Palmer — I would like to thank my mentor,
Professor Knapp, and the Undergraduate Honors
Fellowship program for continued support and guidance.
Troy Pepping — I would like to thank SIT Study
Abroad for providing this wonderful opportunity, as
well as Jay Turner and Matt Malten for recommending
me for the program.
Anthony Pham — I would like to thank the
laboratory of Dr. Scott Saunders for the opportunity
to participate in this research project, especially
Beth Viviano for her mentorship while I’ve worked in
the Saunders Lab. Finally, I’d like to thank my family
for their continual support and encouragement of my
pursuits
Jackson Pitts — I would like to thank Professor Alex
Seidel and Julia Wildeboer.
Michael Post — Howard Hughes Medical Institute,
SURF Program, and the Maurer Group.
Eric Potter — Special thanks to Dean Joy Kiefer and
Ms. Kristin Sobotka for making this wonderful
opportunity possible. Thank you also to Dr. Kelly
Botteron and her staff for giving me an incredible
research experience.
Travis Proctor — Undergraduate Honors Fellowship
Dr. Roshan Abraham Dr. Daniel Bornstein
Aditya Radhakrishnan — I would like to thank
Dr. Niraj Tolia for giving me the opportunity to work
in his laboratory. In addition, I would like to thank
Jacob Zahm, Nicole Salinas, and Edwin Chen who
actively helped in my research. Finally, I would like to
thank my parents for supporting me.
Sara Rasmussen — Dr. Benson, Research Advisor
Dr. Stoner, Major Advisor
Vinod Ravikumar — I would like to thank Alexey
V. Glukhov, Vadim V. Fedorov, Igor R. Efimov for
providing me with the independence to pursue an
independent project. I would like to thank the lab as
well for the support they have shown me. And finally, I
want to thank Ravi, Jayanthi, and Deepak for their
support.
Laura Rayhel — Dr. Mark Conradi, Christine
MacDonald.
PRESENTERS’ ACKNOWLEDGEMENTS
Benton Reynolds — I wish to thank Amy O’Brien,
Joshua Siegel — Special thanks to: Steve Petersen,
Kurt Wall — I would like to thank Dr. Brody and
for recommending me to apply for this scholarship,
and Frank Hockett and Dr. Lanza for helping me in
my work.
my mentor, for everything. Alex Cohen for
programming help Joe Dubis and Alecia Vogel for
abounding assistance and patience. All members of the
Petersen/Schlaggar lab
the entire Brody Lab for giving me the opportunity to
work with them over the summer. I would also like to
especially thank Dr. Christine MacDonald for her
excellent guidance and support.
Emily Silber — Professor Deroo, Professor Childs,
Professor Loewenstein, Professor Coleman.
Marcus Walton — I would like to thank my mentor
Fady Riad — I would like to thank Dr. Angelaki for
her support of this project.
Nicole Rockweiler — The author would like to
thank Christina Taylor for many valuable discussions
and guidance and Garland Marshall for his wonderful
advice.
Aeron Small — I wish to thank Dr. Harbour, Katie
Alyse Rooks — I would like to thank the Office of
Andrew Stein — I would like to thank Dr. Kathryn
Undergraduate Research for providing me with the
opportunity to fulfill my research. I would also like to
thank my mentor, Ignacio Sanchez Prado, for helping
stay on track with my research.
Miller for allowing me to work in her lab. I also want
to thank Mamiko Isaji and Deborah Frank for guiding
me through my project. Finally, I would like to thank
all members of the Miller Lab for the advice they
provided me with respect to my project.
Matthew Rosenfeld — I would like to thank my
Golder, Mike Onken, and everyone else in the lab that
helped make this summer's research possible.
Writing 1 teacher, Bethany Daniels. Without her
insight and guidance, I would not be able to experience this amazing opportunity.
Alex Strauss — Tyson Research Center Researchers
and Staff, Tyson Research Center’s Aquatic Team,
Kevin Smith.
Jacob Rubens — I would like to thank our advisors
Barbara Honchak, Aaron Collins, and Lawrence Page.
Without them none of our work would be possible.
Joseph Stromberg — Sincere thanks to Miriam
Channah Rubin — I am grateful to have been
supported by the Undergraduate Research Office in
carrying out my research this far. I would also like to
thank my project adviser, Professor Loewenstein, my
partners, Alex Hoogland and Melanie Mohn, and the
whole of the Spenser Project.
Adam Salazar — In addition to the contribution
of my mentor, Carolyn Cannon, I would like to
acknowledge Kathryn Akers, Mary Baumann and
Michelle Farberman for their advice and support.
Kettler and the Buder Center for American Indian
Studies, the Environmental Studies Program, Bret
Gustafson, Matthew Fry, Clare Palmer, Craig Howe of
Oglala Lakota College, the Re-member organization,
Jerome and Theresa High Horse, and the Oglala Sioux
Tribe of Pine Ridge
Daniel Sun — I would like to thank Dr. Erik
Herzog, Alexis Webb, and the rest of the Herzog lab
for their guidance and encouragement. Thanks to the
Animal Facility for their support and the Office of
Undergraduate Research for the opportunity to present
this work.
Stefan Santiago — Thanks to my advisor Younasse
Tarbouni for his guidance and also thanks to David
Mark Reyes for his photography and companionship
during travel. Many thanks to Nabila Jaber for securing
interviews in Rabat, Morocco and finally, thanks to
Mohammed al-Hammadi, Master Musician of Jajouka
for his time.
Dharmesh Tank — I wish to thank Narendrakumar
Pascal Schaefer — I gratefully acknowledge the
Anca Timofte — I would like to thank Professor
assistance of the Elson Lab members in particular Elvis
Lee, Sam Safran, Kathryn Miller, Jordan Whisler, Yosef
Gillers, Dan Feng, Rabbi Hershey and Chana Novack
from Chabad on Campus, and my very supportive
family.
Young-Shin Jun,the entire Environmental
Nanochemistry Laboratory research group and my
family for their support.
Vanessa Schroeder — I would like to thank my
mentors Kevin G. Smith and Jon Chase for their guidance and support as well as everyone at the Tyson
Research Center who made this project possible. I
would not have been able to complete this project
without the invaluable support of all those involved.
Raphael Schwartz — We would like to thank the
following people and groups: Professor Arye Nehorai,
Phani Chavali, Patricio La Rosa, Ed Richter, Joshua
York, Matt Meshulam, Brian Blosser and the WUSTL
Department of Electrical and Systems Engineering.
Brent Sherman — I would like to thank Professor
Lo, Sándor Kovács, Chris Singer, Maria Stoica, Alex
Cassady, and Nathan Fine for their help and support. I
would also like to thank my parents for their love and
gentle guidance.
Xin (Cissy) Si — I would like to thank Dr. James
Cheverud and Elizabeth Norgard, as well as the rest of
the Cheverud lab for their help and support.
Braden Sidoti — I would like to thank the
Ramanan, Cong Lucy Li, and the rest of the Ramanan
Lab for their invaluable assistance, making my summer
both productive and enjoyable.
Jewell Thomas — Dr. Abraham Snyder, Dr. Kevin
Black, Dr. Huiling Peng, Dr. Joe Mettenburg,
Dr. Beau Ances
Connie Tsai — I would like to thank HHMI/SURF
for supporting my research and for the opportunity to
present my work. I would also like to thank Drs. Erik
Herzog and Luciano Marpegan, Ms. Tatiana Simon
and members of the Herzog lab and the Kranz lab, for
all their support and guidance.
Jennifer Varriano — I would like to thank my
mentor Dr. David Peters for allowing me to conduct
helicopter research and to experience the satisfaction in
reaching applicable conclusions. I would also like to
thank my advisor Mr. Ron Laue for guiding me
through the research program and all its opportunities.
Sandeep Venkataram — I would like to thank
Scott Doniger for his blast parsing scripts.
Paul Vithayathil — I would like to thank Dr.
Coopersmith for the opportunity to work in his lab. I
would also like to thank Dr. Clark and everyone else in
the lab for all their help.
Edgar Walker — I would like to thank Dr. Dennis
Barbour, my P.I., for his continual support throughout
the project and in allowing me to explore the project
topic freely at my own pace and interest.
Washington University Computer Science
Department, and anyone who helped on this project;
especially Robert Glaubius, Terry Tidwell, David Pilla,
Justin Meden, William D. Smart and Christopher Gill.
60
Dr. Yufeng Mao of the history department and Dean
Sobotka from the Undergraduate Research
Department for making this possible.
Charles Wang — I wish to thank Maria Kostakioti
and Maria Hadjifrangiskou for their valuable assistance. I also wish to thank Dr. Scott Hultgren, Jerry
Pinkner, and the entire Hultgren lab. Finally, I wish
thank HHMI and the Washington University College
of Arts and Sciences for their generous funding.
Kai Wang — James Watling and Caleb Hickman,
Eric Lee and Michael Kim, John Orrock.
Nicholas Wilbar — I would like to thank Professor
Asad Ahmed for his contribution of both time and
expertise and would like to the Office of
Undergraduate Research, without the generosity of
which the study would not have been possible.
Lynn Wilkie — I would like to thank Pascal Boyer,
Lars Lodgberg, and Kristin Sobotka.
Austin Wilmot — I wish to thank Dr. Phyllis Stein
for providing this wonderful opportunity.
Maxim Wolfson — Special thanks to Nora G.
Pencheva, Zsuzsanna Sidlo Ph.D., Jyoti C. Patel
Ph.D., Margaret E. Rice Ph.D., Sackler Institute of
Graduate Biomedical Sciences of New York
University’s School of Medicine Summer
Undergraduate Research Program.
Jeannette Wong — I would like to thank the students from the 2005 and 2006 classes for Bio4342, as
well as Wilson Leung, Chris Shaffer, and Dr. Elgin.
Dennis Woo — I would like to thank Arpita Kalla
Vyas, Kai-Chien Yang, Patrick Y. Jay, and Paul W.
Hruz for previous work done on the TG9 model.
Hannah Wroblewski — I would like to thank my
mentors in this project for their encouragement and
generosity: Robert Mach, Jinbin Xu, and Lynne Jones.
I had such a wonderful experience researching with
them in the SURF program this summer.
Chen Xu — I would like to thank the Howard
Hughes Medical Institute and Imaging Sciences for the
funds to pursue my undergraduate research project. I
would also like to thank Dr. Joel Perlmutter for his
guidance and support during this extraordinary
academic experience.
Ceren Yalaz — I would like to thank Katherine
Weilbacher, Emanuella Heller and the rest of the
Weilbaecher lab for their incredible mentorship and
endless support during my research experience.
Hao Yang — We would like to thank the entire
members of the Elgin lab for their help and
contributions towards this project.
Cong Yu — I would like to thank Jordan Birch,
Bethany Kassebaum, Enrique Izaguirre, and Daniel
Low for their invaluable assitance and support for my
project throughout this summer.
Bo Zhang — I would like to thank everyone who
made this project possible. The first person would be
my advisor Professor Sarra. I couldn’t have done it
without the support of my grandmother and aunt, and
all my host families.
We are grateful for the generous support provided by the following organizations
that have sponsored many of the projects presented today:
Air Force Research Laboratory
American Recovery and Reinvestment Act Research Grant
American Society of Hematology
Arnold and Mabel Beckman Foundation
Baseload Energy, Inc.
Burrows Wellcome Career Award
Children’s Discovery Institute (CDI)
Communities Healing Adolescent Depression and Suicide Coalition (CHADS)
The Gary Hirsch Scholarship
(The Center for the New Institutional Social Sciences)
Howard Hughes Medical Institute
Johanna D. Bemis Trust
Midstates Consortium for Math and Science
NASA Missouri Space Grant Consortium
National Cancer Institute
National Endowment of the Humanities
National Institute of Standards and Technology
National Institutes of Health
National Science Foundation
Norman Hackerman Advanced Research Program, The Welch Foundation
Sigma Aldrich
Sigma Xi Scientific Research Society, Washington University Chapter
St. Louis Children’s Hospital
Washington University in St. Louis:
Center for the Study of Ethics and
Human Values
McDonnell Center for the Space Sciences,
Robinson Award
Cognitive, Computational and Systems
Neuroscience Summer Undergraduate
Research Experience
McKelvey Scholarship
BioMedical Research Apprenticeship Program
(BioMed RAP)
Buder Center for American Indian Studies
Delos Award
Career Center
Engineering Student Council (EnCouncil)
Office of Undergraduate Research,
Catherine F. Hoopes Endowment
Consortium for Clean Coal Utilization
Environmental Studies Program
Rowe Travel Fellowship
Department of Art History and Archaeology
Fossett Fellowship for Environmental
Sustainability Research
Gephardt Civic Engagement Fund
School of Medicine
Department of Anatomy and Neurobiology
Department of Pathology and Immunology
Department of Performing Arts
I-CARES
Siteman Cancer Center
Department of Physics
Imaging Sciences Pathway
Tyson Research Center
Center for Joint Projects in the Humanities
& Social Sciences
International Activities Fund for
Undergraduates in Arts and Sciences
Undergraduate Honors Fellowship
Center for Materials Innovation
Lennette Undergraduate Research Fellowship
Undergraduate Scholars in Transition to
Advanced Research (Ustar)
Lien Undergraduate Research Award
W.H.R. Rivers Summer Research Award
Andrea Biggs Undergraduate Research Award
Bemis Scholarship, Interdisciplinary Project
in the Humanities
Department of Electrical and Systems
Engineering
Mellon Mays Undergraduate Fellowship Program
Nano Research Facility
Participants also wish to acknowledge the support of their research mentors, many of whom have
contributed funding from their grants to support undergraduate research experiences.
THANK YOU
The Office of Undergraduate Research would like to thank the following people
for their support of the Fall 2009 Undergraduate Research Symposium:
Nicole Bobbitt
Danny Guenther
Josh Hasam
Kelly Hill
Ed Hiss
Andrew Hoekzema
Ron Laue
Jennifer Marchal
Yifan Meng
Amy O’Brien
Tijana Orescanin
the Phage Hunters
Elizabeth Riley
Allison Schroeder
Claire Segar
Greg Sergay
Washington University Event Services
OFFICE OF UNDERGRADUATE RESEARCH
http://ur.wustl.edu
[email protected]
Henry Biggs, Director
Joy Kiefer
Kristin Sobotka
Jennifer Kohl
Tim Bono
Sandro Santoro
UNDERGRADUATE RESEARCH SYMPOSIUM
FALL 2009
Saturday, October 24, 2009
8:50 a.m. – 4:00 p.m.
Laboratory Sciences Building