The 5th
Annual
NC
Undergraduate
Summer Research Symposium
NSF Alliances for
Graduate Education
and the Professoriate
(AGEP) SRE
Abstracts are listed in
alphabetical order by the last name of the corresponding author.
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Arribas, Ricardo L. Petzold, Jennifer |
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Program: |
NSF Alliances for Graduate Education and the Professoriate (AGEP) |
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Department(s): |
Biological Sciences |
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Research
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Fred Gould/Entomology |
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Title
of Presentation: |
Physical Responses of Physalis
Leaves to H. sublexa Eggs |
Plant- insect interactions include
many different types of relationships, some of which are negative for the
plant. Plants have evolved defenses against many different threats; one of
these defenses is the formation of undifferentiated cells where insects oviposit
on the leaf. This kind of response can be observed in Physalis plants when H.
sublexa moths lay eggs on the plant. Reaction to H. subflexa eggs on the
surface of Physalis leaves may be a defense response specific to this
herbivore, and it may result in a decrease in the percent of eggs that hatch.
The purpose of this study was to 1) characterize the reactions on Physalis
leaves caused by H. sublexa oviposition, 2) determine if percent hatch is
affected for eggs under which the plant has reacted versus eggs lacking a plant
response, and 3) determine if this reaction is specific to H. sublexa or if the
plant reacts to other Lepidopteran insect oviposition. Reactions to eggs were
characterized for three Physalis species--P. pubescens, P. angulata, and P.
cordata. The responses were identified as two types: a) a discoloration of the
leaf directly under the egg, forming a yellow circular patch that increased in
diameter over time and eventually resulted in tissue death, and b) a
proliferation of cells in the shape of a volcano under the egg, varying in
size. Preliminary results revealed that 44% of eggs to which the plant reacted
hatched, while only 29% of the eggs with no plant reaction hatched, meaning
that a reaction by the plant may not affect the eggs in a negative way. It is
possible that the Physalis plant is reacting to oviposition with the purpose of
pushing the egg off the plant to prevent feeding damage, or to make it easier
for predators to attack the egg.
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Barr, Amy M. Patel, Mukund |
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Program: |
NSF Alliances for Graduate Education and the Professoriate (AGEP) |
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Department(s): |
Biological
and Environmental Sciences Genetics |
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Research
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James W. Mahaffey/Genetics |
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Title
of Presentation: |
Identification and Characterization of
Protein Interactions with the Drosophila Disconnected
(disco) Gene |
Most animals have a segmented body, with morphological
distinctions in the segments along the anterior/posterior body axis. These
differences are established during development by differential expression of the Hox homeodomain
transcription factors along the body axis. The different Hox proteins activate
different sets of target genes, thus creating each unique body segment (for
example, head, trunk, and abdomen). However, it is clear from many studies that
the Hox proteins do not work alone; specific cofactors are needed. The
Drosophila gene disconnected (disco) may encode one such
cofactor that functions with the head Hox proteins. disco is required
for proper larval head development, and in embryos lacking disco the
head segments develop as if they have lost Hox input. Gene regulation is a very
complex process, and even Disco does not function alone. The objective of my
study was to identify other factors that interact with Disco. I employed a
yeast two hybrid assay to identify genes encoding potential Disco
interactors. My initial screen identified 21 clones encoding proteins that
were positive for an interaction. I am now in the process of characterizing
these clones to determine the identity of each gene. Once the genes are
identified, I will begin to address how the encoded proteins participate with
Disco and the Hox proteins to establish segment identities during Drosophila
development. Since the Hox proteins and Disco are conserved in all
metazoans, understanding how these factors contribute to development of
Drosophila will contribute to our knowledge of development in all
animals.
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Belton,
Jon-Matthew |
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Program: |
NSF Alliances for Graduate Education and the Professoriate (AGEP) |
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Department(s): |
Biochemistry |
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Research
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Linda Haley-Bowdoin/Biochemistry |
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Title
of Presentation: |
Immunolocalization of AL1,
Geminivirus Replication Factor, in Arabidopsis Plants Infected with Cabbage Leaf Curl
Virus |
Cabbage Leaf Curl Virus (CaLCuV)
is a member of the Geminiviridae
family of plant viruses. Geminiviruses cause agricultural epidemics world wide,
devastating a variety of crops including cassava, tomato, cotton and
maize. Geminiviruses are characterized by
their small, circular, single-stranded DNA genomes with either one or two
chromosomes and by their double icosohedral viral particles. We used
immunolocalization assays to study the viral replication protein, AL1, in wild
type and mutant lines of Arabidopsis thaliana Col-0. Plants were inoculated with Agrobacterium tumefaciens carrying T-DNA
constructs with the A and B genomes of CaLCuV. Microscopic analysis of
vibratome-generated sections of infected plant tissues revealed the relative
concentrations of virus in specific tissues. This information adds to our
understanding of the infection process in the Arabidopsis model system.
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Blue, Aaron W. He, Peng |
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Program: |
NSF Alliances for Graduate Education and the Professoriate (AGEP) |
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Department(s): |
Chemistry |
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Research
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Lin
He/Chemistry |
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Title
of Presentation: |
Amplification-by-Polymerization in
Fluorescence-based DNA Sensing |
The aim of this work is to
incorporate fluorophores on polymer brushes to enhance DNA detection on a
surface-initiated Atom Transfer Radical Polymerization (ATRP) reaction for
fluorescence measurements. It has been previously discussed that under optimized
ATRP reaction conditions, that the direct visualization of poly (2-hydroxyethyl
methacrylate) PHEMA growth can be observed when running longer reaction times1.
It has also been noted for any DNA-sensing application faster reaction times
are desired1. Incorporating fluorophores
onto polymer brushes has the potential of improving DNA detection sensitivity
and shortening the assay time. In the
concept-proof experiment, ATRP initiator-coupled ssDNA molecules were immobilized
on a gold surface. ATRP polymerization
was then carried out and the amount of PHEMA formed was measured using
ellipsometry. Carbonyldiimidazole (CDI) was used to react with the hydroxyl
groups of the polymer, allowing the attachment of the flourophores
(5-(6)-((N-(5-aminopentyl)amino)carbonyl)tetramethylrhodamine). The successful incorporation of the
fluorescent dyes to the polymers was examined using a fluorescence
microscope. The selection of the proper
fluorescent dyes and coupling conditions were also conducted. The preliminary data show that the
incorporation of fluorescence detection could be used to improve the
performance of polymer-assisted DNA Sensing.
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Caldwell, Ticola S. |
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Program: |
NSF Alliances for Graduate Education and the Professoriate (AGEP) |
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Department(s): |
Psychology |
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Research
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Pamela
Martin/Psychology |
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Title
of Presentation: |
Factors that Contribute or Hinder Achievement
Motivation among Low-income African American Elementary Students |
The focus of this
qualitative study is to examine the multiple factors that influence the reasons
why low-income African American elementary age students are experiencing low
academic achievement. Four educators in the
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Caro,
Eduardo J.E. |
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Program: |
NSF Alliances for Graduate Education and the Professoriate (AGEP) |
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Department(s): |
Chemistry |
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Research
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Christopher B. Gorman/Chemistry |
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Title
of Presentation: |
Effective |
Indanols are important synthetic
intermediates both in pharmaceutical applications and in emerging
polymerization routes under development in the Gorman Group at NCSU. An effective synthetic route was devised to
produce substituted indanols. The synthetic scheme consists of three steps,
using 3,5-dibromobenzaldehyde as starting material. Structure characterization
of each product was obtained through ¹H-NMR.
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Cepero,
Keren J. |
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Home
Institution: |
UPR |
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Program: |
NSF Alliances for Graduate Education and the Professoriate (AGEP) |
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Department(s): |
Forestry Department of Natural Resources |
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Research
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Stacy A.C. Nelson/Forestry Department of
Natural Resources |
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Title
of Presentation: |
Microclimate and Water Quality of Black
Creek Watershed |
Urban streams are faced with
constant pressures from surrounding land uses. Development within the urban
environment contributes to a series of anthropogenic stressors. These stressors
within the aquatic environment including excess sedimentation nutrients and
chemicals may also be amplified by microclimatic conditions within local areas.
The objective of this study was to examine the effect of land use stressors and
water quality and short range microclimate conditions (air temperature,
precipitation, barometric pressure) with in the Black Creek Watershed at
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Edathil, Roshen T. |
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Program: |
NSF Alliances for Graduate Education and the Professoriate (AGEP) |
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Department(s): |
Structural and Molecular Biochemistry |
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Research
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William L. Miller/Biochemistry |
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Title
of Presentation: |
Identification of Transcription Factors
that Partner with Smad3/4 to Induce Transcription of FSH-beta |
Follicle Stimulating Hormone
(FSH) is required for egg and sperm
production in mammals. FSH is an
alpha/beta heterodimer with FSH-beta
controlling overall expression. Because of its importance, FSH-beta is
controlled by more than 6 hormones, one of which is activin-A, a transforming
growth factor beta (TGF-beta) family member.
Activin typically activates Smad3, a nuclear transcription factor, that
then binds Smad4 and other transcription factors to form DNA-enhancesome
promoter complexes to induce gene transcription. One Smad binding site in the FSH-beta
promoter seems especially important for FSH expression (-166GTTTAGAC-159). My goal this summer has been to isolate the
nuclear transcription complex containing Smad3/4 and all other proteins
involved in inducing FSH-beta transcription.
I increased Smad3 concentrations in FSH-producing cells (LbetaT2) by
transient transfection of a Smad3 expression plasmid, isolated the nuclear
proteins and incubated the nuclear extract with biotinylated DNA known to bind
Smad3/4 most efficiently (GTCTAGAC-biotin).
The DNA-Smad3/4-enhancesome
complex was isolated using streptavidin-coated magnetic microbeads that were
captured on a magnetic column. Western
blotting with antibodies was used to show efficient extraction of Smad3/4
(chemiluminescence). Other proteins in
the complex will be identified using HPLC-Mass Spectral analysis. Optimization of this technique using Smad3/4
was necessary to ensure efficient extraction of enhancesome proteins. Characterization of the Smad-associated
transcription factors on the FSHâ
promoter will identify proteins that can partner with Smad3/4 and may be
important in hundreds of other activin-induced promoters.
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Fairey, Donta' J |
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Home
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Program: |
NSF Alliances for Graduate
Education and the Professoriate (AGEP) |
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Department(s): |
Center for Earth
Observation Forestry and Environmental Resources |
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Research
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Justin M. Shedd/Forestry
and Environmental Resources Stacy A. C. Nelson/Forestry and Environmental Resources |
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Title of
Presentation: |
Development of GIS
Techniques for Effective Wetland Delineations |
The
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Gonzalez, Jessica |
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Home
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Program: |
NSF Alliances for Graduate Education and the Professoriate (AGEP) |
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Department(s): |
Chemistry |
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Research
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David A. Shultz/Chemistry |
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Title
of Presentation: |
A Comparison of the Valence Tautomeric
Behavior between (4-X-pyridine) 2Co(diox) 2 Complexes
and (4,4’-di-X-2,2’-bipyridine)Co(diox) 2 Complexes Using Variable
Temperature Infrared Spectroscopy |
A study of the intramolecular cobalt-quinone electron
transfer has been carried out in a series of complexes of general formula
(4-X-pyridine) 2Co(diox) 2 and
(4,4’-di-X-2,2’-bipyridine)Co(diox) 2 where “diox” is 3,5-di-tert-butyl-o-benzosemiquinone/3,5-di-tert-butyl-o-catecholate and X is -H,
-NO2 and -Br. The
(4-X-pyridine) 2Co(diox) 2 complexes and (4,4’-di-X-2,2’-bipyridine)Co(diox) 2
complexes were synthesized and their magnetic properties were analyzed with a
Superconducting QUantum Interference Device (SQUID) magnetometer, while
characteristic optical transitions were probed using Variable Temperature
Infrared Spectroscopy (VTIR) to support the electron transfer between the metal
ion and one of the quinone ligands. The
optical absorptions that appear in the 3700nm region of the infrared for the
Co(III) complexes are assigned to Cat - SQ charge transfer transitions. As the temperature was varied, spectral
changes were observed on this
region. This fact suggests a
thermally-driven valence tautomeric interconversion between Co(II) species and
the Co(III) form in (4,4’-di-X-2,2’-bipyridine)Co(diox) 2
complexes. While in (4-X-pyridine)2Co(diox)
2 complexes, the spectral changes
were not observed, suggesting that the equilibrium may not occur. A mechanism for the differences in valence
tautomeric behavior for these complexes
is offered.
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Hagan,
Diane |
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Program: |
NSF Alliances for Graduate Education and the Professoriate (AGEP) |
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Department(s): |
Textile and Apparel, Technology and
Management |
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Research
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Traci May/Textile and Apparel, Technology
and Management |
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Title
of Presentation: |
Color Variation in Digital Textile Printing:
Influence of Fiber Content and Other Substrate Characteristics |
The purpose of this research is to study variations
in colors that are digitally printed on textile substrates composed of
different fibers, identify major and minor factors that contribute to these
variations, and seek ways to control these variations.
Nine fabrics that differed in weave structure, fiber
composition, and/or preprinted color were characterized according to molecular structure, physical properties, and
pre-printed color (after pretreatment). Based on previous research, these
substrate properties were expected to influence the resulting color in the
printed fabric. A multicolor design was printed on all of the fabrics with a
large format textile printer that used cyan, magenta, yellow, black (CMYK), and
turquoise and orange dye-based inks. Because of the dye affinity of the
selected fabrics, reactive dye inks, as opposed to acid dye inks, were used for
the printing. After fabrics were steamed and washed, coloration differences
were assessed by comparing fabrics visually side-by-side in a controlled
environment and objectively with a colorimeter.
The
color differences made the relationship between the various fibers and the
fixed selection of dyes apparent. The primary factor that affected coloration
differences among the fabrics was the molecular
structure of the fiber in the textile substrate, or the fiber content,
while the minor factors like the preprinted color and weave structure of the
fabric gave only slight variation in the printed color. Many previous researchers have shown that
color management systems (CMS) have been a major way to control the color
discrepancies in digital textile printing. This work demonstrates the
importance of including fiber content of the substrate as a variable in color
management systems.
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Ho, Kiti Han, Sang-oh |
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Program: |
NSF Alliances for Graduate Education and the Professoriate (AGEP) |
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Department(s): |
Molecular and Structural Biochemistry |
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Research
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William L. Miller/Biochemistry |
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Title
of Presentation: |
Searching for Activin Responsive Elements (ARE)
on the Promoter of Ovine Follicle Stimulating Hormone Beta-subunit |
Ovine follicle stimulating hormone beta-subunit (oFSH
beta) is produced by pituitary gonadotropes. It partners with its alpha subunit
to regulate the development of sperm and eggs, thus controlling fertility in
all vertebrates. One of the hormones that regulates oFSH beta expression is
activin. Activin belongs to the transforming growth factor beta super family
(TGF-beta), which controls the development of most cells in the body until they
become fully differentiated. Regulation of oFSH beta by activin serves as a
model for studying activin action on many genes in numerous cell types. It is
still not clear, however, how activin stimulates oFSH beta. Studies have
discovered one ARE on the oFSH beta promoter, which is between -166 bp and -159
bp, but this element, by itself, is not enough to account for the potent effect
of activin. Our goal is to define all ARE sites on the oFSH beta promoter. In
order to achieve this goal, we used two approaches. One is by deletion
mutagenesis, which deletes promoter sequences and looks for loss of activin
action. A side effect of deletion analysis is that certain promoter sequences
are brought closer to the transcription starting point, which can falsely alter
activin action. The other approach is to replace DNA sequences with spacer DNA.
This approach does not change spacing. In this project, I studied the -750/-169
region of the promoter. I found a loss in activin induction when I deleted this
element or replaced it with spacer DNA, indicating that ARE site(s) exist(s)
within this region.
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Hume, Samuel |
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Program: |
NSF Alliances for Graduate Education and the Professoriate (AGEP) |
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Department(s): |
Electrical and Computer Engineering |
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Research
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Winser
Alexander William
Edmonson |
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Title
of Presentation: |
A Comparison of Tools Used to Analyze System
Characteristics of Biochemical Models |
The project involved an evaluation of two simulation
packages along with the use of the Systems Biology Markup Language (SBML) to
describe and analyze biological systems. Identifying a unified way to describe
and analyze biological systems in
software is a critical component of system biology research. It is a necessity
to have information standards if models are
to be shared, evaluated, and cooperatively developed.
Otherwise, a considerable amount of time would be spent translating biochemical
reactions models from one representation to another, and valuable information could be lost in the process. The Systems Biology Markup Language (SBML) is
a free and well-accepted XML-based language for representing and
exchanging models between simulation and analysis
tools. The SBToolBox for MATLAB and the
Systems Biology Workbench (SBW) were the simulation packages used in the evaluation.
The metrics used for performing the
comparative analysis of the above tools were: steady-state analysis, stability
analysis, simulation time, in-silico experiments, bifurcation analysis,
parameter estimation, and parameter sensitivity. The goal for the project was
to provide information for use to decide which tool is better suited for the
analysis of a given model.
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Kelley, Lauren N. |
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Home
Institution: |
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Program: |
NSF Alliances for Graduate Education and the
Professoriate (AGEP) |
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Department(s): |
Microbiology |
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Research
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Hosni M.
Hassan/Microbiology Matthew R. Evans/Microbiology |
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Title
of Presentation: |
The
Impact of Varying Concentrations of Paraquat on SOD Activity of Log-Phage
Cells of Salmonella enterica Typhimurium
ATCC 14028s |
Oxygen toxicity plays an important role in cellular injury
as well as in many common diseases, and is controlled by a balance between the
rates of generations of reduced oxygen species and the removal of those
species. Superoxide dismutases are metalloenzymes that are essential for the
defense against oxygen toxicity. Redox cycling compounds such as the herbicide
paraquat (PQ), propagate the formation of the superoxide radicals ( .O2
- ). Superoxide dismutases
(SODs) catalyze the dismutation of superoxide radicals ( .O2
- ) to hydrogen peroxide and oxygen. Salmonella enterica Typhimurium is an intracellular pathogen that
infects human and causes gastroenteritis. However it causes typhoid-like fever
in mice. S. Typhimurium possesses three types of SODs, which are copper and
zinc (CuZnSOD), manganese (MnSOD), and iron (FeSOD). The goal of this project
was to study the effect of paraquat on growth and synthesis of SODs in
logarithmic phase cells of S. Typhimurium. S.
Typhimurium was grown in LB-MOPS medium
containing 20mM xylose. Log phase cells were exposed to different
concentrations of paraquat (0 .0, 0.3, 0.5, and 1.0mM) starting at an OD600 of
0.3. Aliquots were taken prior to exposure to PQ and every 15 minutes
thereafter until 75 minutes had elapsed.
A
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Khan, George |
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Program: |
NSF Alliances for Graduate Education and the
Professoriate (AGEP) |
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Department(s): |
Forestry
& Environmental Resources |
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Research
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Ross
Whetten/Forestry & Environmental Resources |
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Title
of Presentation: |
Pilot
study to Investigate Chemically Induced Resistance in Fir Species (Abies
spp.) against Phytophthora cinnamomi |
Phytophthora root rot and stem canker is one of the
most important diseases of Abies species that are grown as Christmas trees. For
example, root rot, caused by Phytophthora cinnamomi is a serious problem on
Fraser fir in nurseries and Christmas tree plantations in western
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Student Author(s): |
Lawrence, Charlie III Morris, Eric B. |
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Institution: |
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Program: |
NSF Alliances for Graduate Education and the
Professoriate (AGEP) |
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Department(s): |
Forestry
& Environmental Resources |
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Research
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Glenn
P. Catts/Forestry and Environmental Resources |
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Title
of Presentation: |
Application
of Spatial Technology to the Field
Assessment of Soil compaction Resulting from Equestrian Activity |
Excessive soil compaction can negatively influence soil
productivity and water quality for long periods of time. Horse traffic on
forest trails causes soil compaction. Soil compaction is recognized as a
field indicator of sustainable forest
management.
Horseback
riding is a recreational activity that occurs with regularity on
We
applied cost efficient spatial technology to map and assess the compaction
suffered on horse trails on the
Variables
describing elevation, slope, soil type, distance to hard surface roads and
perennial streams were extracted from public domain GIS data and used to select
locations for field sampling. Field sampling was accomplished using
custom-configured data entry forms at selected locations while taking
penetrometer readings of soil compaction in transects perpendicular to the
direction of and across selected horse
trails. Subsequent analysis compares the degree of compaction measured by the
penetrometer as a function of one or more of the field-collected or GIS-based
variables.
At the request of the
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Lopez, Harry O. Kirst, Mariana E. Holmes, Robert A. |
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Home
Institution: |
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Program: |
NSF Alliances for Graduate Education and the
Professoriate (AGEP) |
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Department(s): |
Biology Plant
Biology |
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Research
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Rebecca
S. Boston/Plant Biology |
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Title
of Presentation: |
Production
of Recombinant Maize Ubiquitin Conjugating Enzymes in E.
coli |
The endoplasmic reticulum (ER) is an organelle formed
from a network of membranous tubules equipped with molecular chaperones and enzymes
essential to protein folding. Correctly folded proteins are exported from the
endoplasmic reticulum, while misfolded proteins are retained and selectively
degraded by a process known as ER-associated degradation (ERAD). We used
bioinformatic tools to identify putative maize homologs of several proteins
implicated in ERAD processes in other organisms. Ubiquitin conjugating enzymes (Ubc1p &
Ubc6p) are cytosolic proteins that mediate targeting of short-lived and
abnormal proteins for degradation. Hydroxymethyglutaryl reductase degradation
protein (Hrd1) is an ER membrane protein that facilitates proper degradation of
misfolded membrane proteins. Our goal was to produce recombinant maize Ubc1p,
Ubc6p and Hrd1 proteins in an IPTG-inducible E. coli expression system for antibody production and protein
interaction studies. We used a pRSET plasmid vector to produce a fusion protein
with polyhistidine and Xpress® epitope tags in-frame with the maize protein
coding sequences. Recombinant protein production was assayed under different
growth temperatures, induction times, nutrient media and +/- ethanol. Protein
solubility was determined by extracting protein under conditions that allow for
separation of soluble protein and inclusion bodies. For detection of recombinant
proteins, we used a combination of western blotting and general protein
staining of SDS-polyacrylamide gels. For soluble Ubc6p a large-scale production
and purification yielded 2.45 mg/L.
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McLean,
Roshaunda L. |
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Program: |
NSF Alliances for Graduate Education and the Professoriate (AGEP) |
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Department(s): |
Psychology |
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Research
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Rebecca
Stelter/Psychology Amy
Halberstadt/Psychology |
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Title
of Presentation: |
The Relationship between Socio-economic
Status and Stress in African-American Parental Emotional Availability |
Previous research suggests that parents’ emotional availability
can influence children’s emotion-related behaviors, but how parents develop
this emotional availability is not yet known. Thus, the goal of this study is
to explore the distal factors that might influence parents’ willingness to
actively participate in a conflict discussion. I hypothesized that factors such
as stress and socio-economic level are predictors of parental emotional
availability (e.g., providing support, requesting and providing information,
acknowledging child’s feelings, and going along with the other). The more
stressed and the lower the SES of the parent, the less engaged or emotionally
available a parent will be in discussions with their child. A subset of the full sample of African-American
parents and children filled out questionnaires and participated in a videotaped
problem-solving discussion about one or more current conflicts that they
experience with each other. The standard measure for stress is the Daily
Inventory of Stressful Events (DISE), which requests parents to recall specific
types of stress they experienced in the last 24 hours. SES was measured based
on income and educational indices. Emotional availability was globally coded
from seven minutes of the parent-child conflict discussion, using a Likert-type
scale. Results and implications of findings will be discussed.
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Moses, Lorra S. |
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Institution: |
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Program: |
NSF Alliances for Graduate Education and the Professoriate (AGEP) |
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Department(s): |
Molecular
and Structural Biochemistry |
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Research
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Carla Mattos/ Molecular
and Structural Biochemistry |
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Title
of Presentation: |
Purification
of Raf-RBD-CRD for Crystallization |
Raf is a downstream effector protein of Ras in the growth
Mitogen-Activated Protein (MAP) Kinase pathway.
It is a large protein of about 648 amino acids and contains several
domains. Two of the domains bind
directly to Ras. These domains are the
Raf- Ras Binding Domain (Raf-RBD) and the Raf-Cysteine Rich Domain
(Raf-CRD). There are published
structures of Raf-RBD alone and of
Raf-CRD alone, but there are no structures of the two domains together
or of the two domains bound to Ras.
Therefore the main purpose of this research is to purify the protein Raf-RBD-CRD
to be crystallized and to crystallize Raf –RBD-CRD bound to Ras making a
complex. Raf amino acids 1-186 were cloned into the GEV2
vector which was transformed into the E. coli cell line (BL21[DE3]) for
expression of the Raf protein. The E. coli
cells were grown in LB media containing ampicillin and allowed to over express
the Raf protein. The Raf protein was
expressed with a! HIS-tag in order to
purify it by nickel affinity chromatography. Further purification was preformed using anion exchange
and gel filtration chromatography. SDS Page indicates that purification needs
optimizing in order to remove impurities still present. The future direction of this project is to
continue to purify and crystallize Raf to solve the structures by X-ray crystallography.
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Munilla,
Samuel R. |
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Home
Institution: |
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Program: |
NSF Alliances for Graduate Education and the Professoriate (AGEP) |
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Department(s): |
Computer Science |
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Research
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R. Michael Young/Computer Science |
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Title
of Presentation: |
Zocalo, an Integrated Planning Framework
for Use in Diverse Environments |
Narrative plays a critical role in the way we communicate,
learn and interact with one another. Computer systems that take advantage of
this natural inclination towards narrative can present information to the user
in a much more cohesive and engaging
manner than is possible using conventional methods. To this end, the Zocalo Project integrates a
set of planning agents that work together to fulfill a set of goals inside a
virtual environment, while still
presenting an organized narrative to the user. The three primary components of the Zocalo
framework are: Fletcher, a web service that utilizes Crossbow, a partial-order
planner based on the DPOCL (Decompositional Partial Order Causal Link)
algorithm; Crosswind, a web service that provides Reactive Mediation by
creating and maintaining Policy Tress; and Kyudo, a web service that provides
Proactive Mediation. Communication
with this framework is handled by an
Execution Manager, which acts as a bridge between the framework and the 3d
Engine that renders the virtual world.
In order to demonstrate the capabilities of this framework, an
interactive environment was created using Epic’s Unreal2 engine. This environment presents the user with a
single end-goal and allows the user to move about the environment freely. In the background, the Zocalo framework works
to present the user with opportunities that will allow him or her to reach that
goal.
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Muñoz, Jessian L. Gore, Jesse A. |
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Home
Institution: |
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Program: |
NSF Alliances for Graduate Education and the
Professoriate (AGEP) |
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Department(s): |
Biochemistry |
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Research
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William
L. Miller/Biochemistry |
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Title
of Presentation: |
Gonadotropin Releasing
Hormone Inhibits Activin-Induced
Transcription Complexes on the Ovine Follicle
Stimulating Hormone Beta Promoter |
Follicle Stimulating Hormone (FSH) is an alpha/beta
heterodimeric glycoprotein which is required for reproductive function of all vertebrates. Activin
plays a major role in the production of FSH as it induces FSH beta production.
Gonadotropin releasing hormone (GnRH) is a decapeptide produced in the
hypothalamus, which induces FSH beta expression through a MAP kinase pathway. Induction requires pulsatile GnRH release (5
min each hour). Our laboratory has shown, however, that when gonadotropes are
treated with GnRH at high, chronic levels, GnRH can inhibit activin-induced FSH
beta expression, perhaps, through a cAMP/CREB pathway. I used electrophoretic mobility shift assays
(EMSAs) to determine if GnRH treatment could disrupt FSH beta promoter
complexes known to be important for FSH beta induction by activin. LbetaT2
cells were treated with activin ± GnRH and
their nuclear proteins were then incubated with SMAD3/4 binding sites. These
are DNA sequences on the FSH beta
promoter known to bind SMADs which are proteins induced by activin. I
found that these SMAD3/4:DNA complexes were,
indeed, disrupted by GnRH. Through our experimentation, we were able to
show that GnRH inhibits a key transcriptional complex needed for activin
induction of oFSH beta transcription. This is the first example of a hormone
being able to block activin induction at a transcriptional level.
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O'Neal, Zeltina D. |
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Home
Institution: |
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Program: |
NSF Alliances for Graduate Education and the
Professoriate (AGEP) |
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Department(s): |
Biology |
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Research
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Amy
M. Grunden/Microbiology |
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Title
of Presentation: |
Expression and Biochemical
Characterization of
Pyrococcus furiosus Prolidase Homolog-2 for Potential Use in Organophosphorus
Nerve Agent Detoxification |
Study of prolidase enzymes isolated from the
hyperthermophilic archaeon Pyrococcus
furiosus for use as potential detoxification agents against toxic
organophosphorus (OP) compounds has been ongoing. It has been shown that prolidases can
hydrolyze the characteristic P-F and P-O bonds found in the toxic nerve agents
soman and sarin. The P. furiosus prolidase is an attractive
candidate enzyme for OP agent detoxification because it is extremely
thermostable. However, even though P.
furiosus prolidase can withstand higher temperatures, it has some
disadvantages. It requires the addition
of the metal ion Co2+ for activity and has little activity below
50°C. For these reasons, other enzymes
with homology to P. furiosus
prolidase are being studied as alternate decontamination agents. Recently a prolidase homolog was identified
in the P. furiosus genome, prolidase
homolog 2, which has 43% similarity to the previously characterize P. furiosus prolidase. For this study, the P. furiosus prolidase homolog 2 was cloned into the T7 RNA
polymerase-base expression vector pET-21b.
The recombinant P. furiosus
prolidase homolog 2 protein was over-expressed in Escherichia coli strain BL21(λDE3) using both LB and
autoinduction media. Experiments were
conducted to demonstrate the thermostability
of recombinant P. furiosus
prolidase homolog 2 and evaluate its substrate and metal preference.
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Onori, John E. |
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Home
Institution: |
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Program: |
NSF Alliances for Graduate Education and the
Professoriate (AGEP) |
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Department(s): |
Polymer
and Color Chemistry |
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Research
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Richard
Kotek/Polymer and Color Chemistry |
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Title
of Presentation: |
Viscosity
Measurements of Cellulose in ED/KSCN Salt System |
Cellulose is a natural polymer which is found in trees
and plants and is commonly used for making milk and juice cartons. The problem
with cellulose is that it does not melt and dissolve in the common solvents.
Cuen (copper-Ethylenediamine complex) solution is the only solvent used for
viscosity measurements of cellulose. The objective of this experiment is to
take a similar solvent like potassium
Thiocyanate Ethylenediamine system, dissolve different types of cellulose and take viscosity measurements to find there
intrinsic viscosities. Each cellulose sample was ground up, dried in a vacuum
oven over night and measured on an analytical balance. 50 ml glass reactor
equipped with a mechanical stirrer was used for dissolution. Ethylenediamine
and potassium Thiocyanate were added in first to create the solvent, and then
the cellulose sample was added in, it took about 24-48 hours for the complete
cellulose dissolution. An Ubbelohde viscometer, the constant temperature bath
(held at 25oC) and a stop watch was used to determine the flow times of each
solution. Intrinsic viscosity was calculated using a series of equations that
included relative, specific, reduced, and inherent viscosities. Intrinsic viscosity was found by plotting
reduced and inherent viscosity vs. cellulose concentration and extrapolating
reduced and inherent viscosity back to the zero concentration. These two
viscosities should meet at the same point. We were successful in finding the
intrinsic viscosity of AV CELL and Tycell.
Both Inherent and reduced viscosity agreed with each other. Future work will be to use their intrinsic
viscosity to help determine the molecular weight and Degree of polymerization
of AV Cell and Tycell.
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Otero, Ariel O. Ondachi, Pauline W. |
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Home
Institution: |
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Program: |
NSF Alliances for Graduate Education and the
Professoriate (AGEP) |
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Department(s): |
Chemistry |
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Research
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Daniel
L. Comins/Chemistry |
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Title
of Presentation: |
Regioselective
Substitution of (S)-Nicotine and Nicotine Derivatives |
A variety of novel nicotine derivatives were prepared
starting from natural (S)-nicotine. Several functional groups were introduced onto
the pyridine ring of nicotine via a regioselective deprotonation and
substitution of the C-2, C-4 and C-6 positions. The pharmacological effects of
these derivatives on the central nervous system (CNS) and their potential for
cancer treatment will be examined.
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Park, Ji-Seon |
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Home
Institution: |
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Program: |
NSF Alliances for Graduate Education and the
Professoriate (AGEP) |
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Department(s): |
Biochemistry |
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Research
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Robert
B. Rose/Biochemistry |
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Title
of Presentation: |
The
Use of DCoH/HNF-1 fusion Protein as a Tool to Analyze the Activities of a
Bifunctional Protein DCoH |
DCoH (dimerization cofactor of HNF-1) is
a bifunctional protein which functions as a metabolic enzyme in the cytoplasm
and a transcriptional coactivator in the nucleus. In the nucleus, DCoH
interacts with the transcription factor HNF-1alpha (hepatocyte nuclear
factor-1-alpha) and stabilizes HNF-1alpha dimers. Significantly, mutations in
HNF-1-alpha are the most common cause of Maturity-onset diabetes of the young
(MODY). We have generated a DCoH/HNF-1 fusion protein to determine: 1) whether
the two functions of DCoH are independent and 2) how DCoH increases the
transcriptional activity of HNF-1. The DCoH and HNF-1 coding sequences were
linked by Polymerase Chain Reaction (PCR) using a primer overlap strategy and
ligated into a mammalian _expression vector. The DCoH/HNF-1 fusion protein will
be tested for enzymatic activity to determine whether formation of the
interaction with HNF-1 might regulate the enzymatic activity of DCoH. One study
has concluded that DCoH does not lose its enzymatic activity when it is bound
to HNF-1. However, this study did not determine whether the DCoH/HNF-1
complex was stable throughout the study. Structural studies of the
DCoH/HNF-1-alpha complex indicate an active site residue of DCoH is involved in
interaction with HNF-1, suggesting the DCoH/HNF-1 complex should be enzymatically
inactive. The fusion protein will prevent dissociation of the complex during
the enzyme assay. The fusion protein will also allow us to determine how DCoH
increases the transcriptional activity of HNF-1. Our current hypothesis is that
DCoH increases the half-life of HNF-1.
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Plaza, Tomas E. |
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Home
Institution: |
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Program: |
NSF Alliances for Graduate Education and the
Professoriate (AGEP) |
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Department(s): |
Developmental
Psychology |
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Research
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Jason
C. Allaire/Developmental Psychology |
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Title
of Presentation: |
Examining
Health as a Mediator of the Relationship between Education and Cognitio |
Previous studies have found a strong relationship between
education and memory. In addition,
health factors such as physical functioning and mental health have been shown
to be related to education and memory.
Consequently, the aim of this study is to determine whether health
mediates the relationship between education and memory performance. It is expected that health factors will
explain differences in memory performance once attributed to demographic
factors. The sample consisted of 107 urban living African American elders with
a mean age of 71 years (SD = 10.01; range = 52 – 94 years). During testing participants were given a
multifaceted battery, which assessed years and quality of education, working
memory, and subjective health assessments.
Results indicated that years of education and the self-reported quality
of education were associated with working memory as was self-reported
health. Regression analyses revealed
that the effect of education on working memory performance was only partially
mediated by health. Discussion will focus on the importance of assessing
quality of education and its’ association with health and memory.
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Powell, Amanda M. |
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Home
Institution: |
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Program: |
NSF Alliances for Graduate Education and the
Professoriate (AGEP) |
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Department(s): |
Zoology |
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Research
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Brenda J. Grubb/Zoology |
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Title
of Presentation: |
Analysis of the Effect of Estrogen on Claudin Tight Junction
Proteins |
Estrogen plays a vital role in cell differentiation during mammary tissue development. To understand the basic mechanism of estrogen during development, Xenopus frog embryos were exposed to estrogen and an estrogen inhibitor at a critical stage of sensitivity. The embryos were then fixed, embedded and sectioned for analysis of the effect of estrogen on morphogenesis. An E.L.I.S.A was done to test for claudin 4, 5 and 7 protein level changes. Claudin levels were also monitored in mouse mammary tissue using histology. Both tumor and normal mammary tissue was observed for the presence of lack of the proteins. Claudins are a family of tight junction proteins necessary for cell to cell interaction and adhesion. It has been shown that low levels of certain claudins result in metastasis and tumorogenesis. Loss of claudin results in reduced cell adhesion, allowing cells to break away and metastasize. We are trying to monitor the effects of estrogen on claudin levels. It is hypothesized that there is a direct correlation between estrogenic affects on morphogenesis and altered claudin levels.
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Ramirez Vicens, Magaly A. Munro-Leighton, Colleen Delp, Samuel A. |
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Home
Institution: |
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Program: |
NSF Alliances for Graduate Education and the
Professoriate (AGEP) |
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Department(s): |
Chemistry |
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Research
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T.
Brent Gunnoe/Chemistry |
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Title
of Presentation: |
Catalytic
C-S Bond Formation by Monomeric Copper(I) Sulfido Complexes |
Natural products and biologically active compounds
often contain C-X (X = O, N or S) bonds. Thus the development of new catalysts
for C-X bond formation is an important pursuit, including routes for C-S bond
formation. The monomeric Cu(I) complexes
(IPr)Cu(Y), (IMes)Cu(Y) and (SIPr)Cu(Y) (Y = SPh, SCH2Ph; IPr, IMes,
SIPr = N-heterocyclic carbenes) have
been prepared, and these complexes serve as catalysts for the addition of S-H
bonds across double bonds of electron-deficient olefins. Among transition metals,
copper is attractive as a catalyst because of its low expense. The reactivity
of these complexes extends to a variety of olefins including acrylonitrile,
methyl vinyl ketone, methyl acrylate and cyclohexenone.
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Rivera, Ivelisse Stelter, Rebecca |
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Home
Institution: |
Universidad
Metropolitana |
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Program: |
NSF Alliances for Graduate Education and the
Professoriate (AGEP) |
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Department(s): |
Psychology |
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Research
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Amy
Halberstadt /Psychology |
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Title
of Presentation: |
Exploring
Relationships: Parent's Beliefs about Children’s Emotions and Emotional
Availability |
Parents' emotional availability may be an important
component of children's socioemotional lives.This study will examine how parents'
beliefs about emotion may relate to emotional availability with their children.
African American parents and their 9- to 10- year old child participated.
Parents filled out the PBACE, a questionnaire with five subscales about
parents' beliefs about the value, danger and controllability of emotion.
Children filled out the LEAP, a questionnaire about the children's perceptions
of their parents' emotion availability. Predictions are that parents'
valuing of emotion will be associated
with their children's assessing them as emotionally available. Whereas parent's
belief that emotion is somewhat dangerous will be associated with children
perceiving parents as rather distant. Results are forthcoming.
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D'Antonio, Edward L. |
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Home
Institution: |
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Program: |
NSF Alliances for Graduate Education and the Professoriate (AGEP) |
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Department(s): |
Chemistry |
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Research
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Title
of Presentation: |
Diffusionless Electrochemistry of Dehaloperoxidase Electrostatically
Adsorbed to Alkanethiol Self-Assembled
Monolayers |
Dehaloperoxidase (DHP) is a heme enzyme isolated from
the marine worm Amphitrite ornata that has the ability to dehalogenate
trihalogenated phenols. These toxic
aromatic contaminants present a major environmental concern, especially to
aquatic organisms that cannot metabolize haloaromatics. DHP in the presence of peroxide can convert
these halophenols into environmentally less toxic compounds.
A long term goal is to couple DHP to electrodes in order to realize
electrocatalytic reactions. To achieve
this goal it will be necessary to
understand its catalytic mechanism and its electron transfer (ET)
properties. In the present study, the
fundamental ET properties of DHP were
investigated using protein monolayer electrochemistry (PME), a strategy that
involves adsorption of a (sub)monolayer of functional DHP on a biocompatible electrode. DHP, which contains a cationic binding site,
was electrostatically adsorbed onto anionic carboxylic/hydroxy alkanethiol
self-assembled monolayer (SAM) gold electrodes.
To measure ET rates for the Fe
(III) / Fe (II)-oxy redox reaction we used cyclic voltammetry (CV), an
electrochemical technique in which current is
measured as a function of scanned potential (voltage). The initial
research objective was to obtain a well behaved electrochemical response
for adsorbed DHP that exhibited
stability and adequate surface coverage.
This objective was achieved through an optimization study involving the
following parameters: protein purity and
storage conditions, SAM composition and assembly time, and solution conditions
(buffer type, pH and ionic strength).
The formal potential obtained for adsorbed DHP was +0.30 V vs. NHE (phosphate buffer; pH 6.00;
ionic strength = 6 mM; room temperature).
Measurement of ET rate constants is currently underway to complete this
initial study.
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Smith, Mychal D. |
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Home
Institution: |
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Program: |
NSF Alliances for Graduate Education and the
Professoriate (AGEP) |
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Department(s): |
Molecular
and Structural Biochemistry |
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Research
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Carla Mattos/Molecular and
Structural Biochemistry Paul
Swartz/Molecular and Structural Biochemistry |
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Title
of Presentation: |
Mapping the Protein
Binding Surface of Insulin
using The Multiple Solvent Crystal Structure Method |
Insulin is a polypeptide hormone that regulates
carbohydrate metabolism. It is composed of two peptide chains that are linked
together by two disulfide bonds. The aim
of this study is to cross-link insulin crystals in order to perform the
Multiple Solvent Crystal Structures (MSCS) method. Through the use of organic
solvent soaking this method is able to find binding sites, plasticity within
these sites, apolar interactions within the binding pockets, and the role of
displaceable water molecules.
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Smith,
Rondell A. |
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Home
Institution: |
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Program: |
NSF Alliances for Graduate Education and the Professoriate (AGEP) |
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Department(s): |
Animal Science |
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Research
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H.C Sunny Liu/Animal Science |
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Title
of Presentation: |
Protein to Protein Interaction between
PRRS Virus ORF4 and Macrophage Host Cell |
The Porcine Reproductive and Respiratory Syndrome
Virus (PRRSV) infect macrophages of the immune system of swine. The virus belongs
to the Arterivirdae family and is easily spread through nasal secretions,
salvia, among other bodily fluids, and can also be carried airborne for up to 2
miles. This virus is detrimental to swine units because it can cause
infertility and respiratory problems leading to death. Since swine housing is
usually shared the virus has the possibility to affect a large portion of a
group because of its long shedding life. This study was done to explore what
possible proteins are interacting on open reading frame 4 (ORF4) of the virus
infecting the macrophage host cells. ORF4 is important because it is a
structural protein on the outside of the virion by which some interaction
between it and the host cell could take place.
By performing a yeast two-hybrid we intend to identify novel protein
interactions and confirm suspected interactions. With the yeast two-hybrid it
utilizes gene transcriptional factors; binding domains (BD) and activation
domains (AD), and when fused to two separate proteins that interact with one
another the BD and AD are brought together. This allows for transcription to
occur of the reporter gene. Yeast growth is then tested to confirm protein
interaction through colony lift to measure the B galastosidase activity on the
X-gal media and use the lacZ reporter gene which causes positive matings to
turn a phenotypic blue. The Data suggest that some kind of interaction takes
place but whether it helps for cell adhesion, replication, synthesis, or
transport is what is hoped to be identified.
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Stephenson, Tesia N. |
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Home
Institution: |
University of |
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Program: |
NSF Alliances for Graduate Education and the Professoriate (AGEP) |
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Department(s): |
Biological Sciences |
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Research
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Christian
Melander/Chemistry |
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Title
of Presentation: |
Synthetic Studies
Toward a Representative Model Compound of Lomaiviticin A |
Lomaiviticin A is a potent
antitumor natural product isolated from the marine organism Micromonospora lomaivitiensis.
Lomaiviticin A is a novel, homodimeric diazobenzo[b]fluorene glycoside
structure that draws similarities to the kinamycin antibiotic family of
monomeric diazobenzo[b]fluorenes. Lomaiviticin A induces DNA damage under
reducing conditions, and is also effective against gram positive bacteria
including Staphylococcus aureus. Our
goal is to build a model compound monomer to which various glycals can be
attached that will represent the central core of lomaiviticin A. These model compounds could then be tested
for biological activity, and also studied from a mechanistic point of view to
decipher the role the sugars play in interacting with cellular DNA. The key steps in the synthesis are a nickel
catalyzed cross-coupling between a vinyl bromide and grignard reagent. Osmium tetraoxide mediated dihydroxylation
follows to obtain the advanced intermediate.
Methodology work will then need to be done to develop the best conditions
for linking the 2’ deoxy sugars of lomaiviticin A to our monomer scaffold.
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Sepúlveda, Jennifer |
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Home
Institution: |
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Program: |
NSF Alliances for Graduate Education and the Professoriate (AGEP) |
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Department(s): |
Chemistry |
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Research
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T.
Eric Ballard/Chemistry Christian
Melander/Chemistry |
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Title
of Presentation: |
Synthesis of a TAK-779 Gold Nanoparticle
Conjugate: A Highly Potent and
Selective Inhibitor of HIV-1 Replication |
CCR5 is known as the major β-chemokine
co-receptor for the fusion and entry of HIV-1 into host cells. TAK-779 was
identified as a small-molecule nonpeptide CCR5-specific antagonist. Several
chemokine antagonists, including TAK-779, have been recently synthesized in an
attempt to develop anti-HIV-1 agents. However, HIV-1 mutates to bind around the
CCR5-drug complex due to the molecule’s small size. Consequently, over a period
of time, the drug is no longer effective. Therefore, to overcome this problem
we will synthesize a TAK-779 gold nanoparticle conjugate to suppress the HIV-1
replication. We postulate that conjugation of TAK-779 to the gold nanoparticle
will improve drug efficacy by two avenues. First, the size of the nanoparticle
is on the order of a small protein; therefore, it will be difficult for HIV-1
to mutate and infect target cells. Second, the increased local concentration of
TAK-779 on the nanoparticle will vastly improve the apparent affinity. The
eight-step synthesis of our key carboxylic acid intermediate began with
reduction of commercially available 4-(4-methylphenyl)benzonitrile to
4-(4-methylphenyl)benzaldehyde in an 89%
yield by the use of Red-Al at -10˚C in THF. Then, a Wittig reaction of
this aldehyde with (3-carboxypropyl)triphenylphosphonium bromide and 28% NaOMe
in MeOH and followed by hydrogenation at 25 psi overnight led to
5-[4-(4-methylphenyl)phenyl]-4-pentanoic acid in 79% over two steps.
Intramolecular acylation of this resulting acid using PPA at 100˚C
produced 3-(4-methylphenyl)-6,7,8,9-tetrahydro-5H-benzocyclohepten-5-one in a 51% isolated yield. This compound was
treated with sodium methoxide and dimethyl carbonate to produce the
corresponding β-ketoester. The resulting ketone was reduced with NaBH4
at -10˚C in THF/water. Treatment with MsCl/Et3N/DBU and concomitant
hydrolysis with NaOH provided 59% yield of the 2-(4-Methylphenyl)-6!
,7-dihydro-5H-benzocyclohepten-8-carboxylic
acid as the target key intermediate. Further methodological studies will be
addressed to achieve the final TAK-779 gold nanoparticle conjugate, which will
be tested for its potential CCR5 antagonistic activity in cell culture.
[ 2006 Undergraduate
Summer Research Symposium Main Page ]
Last modified June 2006 by Sharon E. Hunt, WordHunting