The 16th Annual
NC State University
Undergraduate Research Symposium
Abstracts
Physical &
Mathematical Sciences
Abstracts
Abstracts are listed in alphabetical order by the
last name of the corresponding author.
- Biological Sciences abstracts
Applied Sciences
(Crop, Poultry, Animal, and Horticultural Sciences)
Ecology, Environmental,
Conservation, Botanical
Molecular,
Biochemical, Genetics, Cell Biology
Zoology,
Physiology, Behavior, Neurobiology
- Design abstracts
- Engineering
and Technology abstracts
- Humanities,
Social Sciences, Psychology abstracts
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Anderson, Trevor E. |
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Department(s): |
Physics |
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Research |
Keith Weninger/Physics |
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Title of Presentation: |
Pure SNARE Proteins for a Complex-Study |
A family of proteins known as SNARE’s
catalyzes many biological events that involve membrane fusion. Specific
interactions among SNARE proteins influence whether or not two membranes will
merge. A deeper understanding of many biological events will result from
greater knowledge of both how the proteins interact with each other, and also
how foreign molecules such as toxins can influence or prevent the whole
process. I have spent the last semester expressing and purifying SNARE proteins
to produce high-purity, concentrated samples for biochemical studies. I have
used these samples to determine the ability of unrelated families of SNARE’s to
assemble into stable complexes.
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Atakturk, Burcu A. |
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Department(s): |
Accounting |
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Research |
Al Chen/Accounting |
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Title of Presentation: |
Evaluating Alternative Strategic Cost Management
Approaches |
This research project analyzes different costing
systems in use and planned to be used in business settings and identify
strengths and weaknesses of each system analyzed. The costing systems
considered include activity-based costing (ABC), Theory of Constraints (TOC)
and Resource Consumption Accounting (RCA). A distinction is also drawn between
traditional cost analysis and strategic cost analysis. Questions addressed
include: What is strategic cost management? What different perspectives on cost
exist? And finally, what is the strategic cost management process? One of the
fundamental ventures of any business is to make a profit. Good cost management
within a business is vital to making profit. There are multiple costing systems
in use today and it is essential to know which is the best
for the current venture. ABC and TOC are two of the most popular costing
systems in use today. RCA, on the other hand, is a relatively new system about
which little is known. It is important to know the difference between these
three systems and how best to utilize each of them, both individually and in
combination with other methods.
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Attarian, Adam |
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Department(s): |
Mathematics |
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Research |
Hien T.
Tran/Mathematics |
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Title of Presentation: |
A Hybrid Optimization Approach for the Optimal
Design of Traveling Wave Tubes |
Traveling wave tubes are common devices with
widespread use in both satellite and terrestial comunications as well as areas such as electronic counter
measures. We present a hybrid optimization approach for the optimal design of
the electron based device based on two independent physics-based design and
simulation codes. In particular, we use the CHRISTINE suite of large signal
codes to model the slow wave circuit, in conjunction with Beam Optics Analysis
to model a multi-stage depressed collector. These two simulation codes will be
combined in a hybrid framework to automate the process of optimizing several physical
parameters while realizing several design constraints. The equations describing
the device properties as well as the objective functions will be discussed, and
examples of optimized TWTs will be presented.
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Blackmer, Amanda C. Kelley, Richard L. |
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Department(s): |
Chemistry |
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Research |
Stefan Franzen/Chemistry |
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Title of Presentation: |
In vitro Assembly of
Synthetically Produced Viral RNA Transcripts |
Red Clover necrotic mosaic virus (RCNMV) provides an
ideal platform to develop a multifunctional particle with specific application
to therapeutic and gene delivery in humans. In
vitro assembly is a controlled method to propagate engineered virus-like
particles in high yield with greater purity than those obtained by plant
propagation. The assembly of the RCNMV capsids is
dependent on the presence of viral RNA. To obtain the RNA for in vitro assembly, we performed
transcriptions of viral RNAs cloned into PUC
expression vectors. These transcript products were characterized using UV/VIS
and agarose gel electrophoresis. The purified capsid proteins were obtained from disassembled wild type
RCNMV. The purity of the protein was confirmed by UV/VIS and SDS/Page gel
electrophoresis. The in vitro
assembly was accomplished by mixing the protein and RNA in a dialysis cassette
at pH 10 and then reducing the pH to 5.5 overnight. Dynamic Light Scattering
(DLS) and Transmission Electron Microscopy imaging (TEM) were done to confirm
the formation of particles. Further experiments will be conducted to access the
in vivo infectivity of the virus-like
particles.
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Brewer, Jason P. Johnson, Matthew S. Thelen, Michael Y. |
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Department(s): |
Marine and Atmospheric Sciences Statistics |
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Research |
William F. Hunt Jr./ Statistics |
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Title of Presentation: |
Protecting Human Health: Modeling the Prevalence of
Fine Particulate Matter in Air Quality Index Reporting |
Fine particulate matter is a significant pollutant
that endangers human health. Small particulates, 2.5 micrometers in diameter or
less, penetrate further into the lungs of humans than larger particulates
leading to increased cases of respiratory diseases and eventual death. Both
annual mean and 24 hour National Ambient Air Quality Standards have been set
for fine particulate matter (PM2.5). PM2.5 is one of five pollutants reported
in the USEPA’s Air Quality Index. It is critically
important that today’s PM2.5 value can be accurately forecasted so it can be
reported to the public with an appropriate health advisory. Our objective is to
develop reliable forcasting regression models to
serve as tools for predicting PM2.5. The regression models will take into account
various meteorological parameters such as temperature, wind speed, wind
direction, and yesterday’s PM2.5 measurements. Our client, Maryland Department
of Environment, provided all meteorological and particulate matter data.
Analyses of selected particulate matter monitoring stations and meteorological
sites in the state of
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Burleyson, Casey D. Bryant, M. Tai |
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Department(s): |
Marine, Earth and Atmospheric Sciences |
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Research |
Sandra Yuter/Marine,
Earth and Atmospheric Sciences |
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Title of Presentation: |
Observation and Analysis of 19 Winter Storm Events
In the |
The purpose of this research is to obtain and analyze
observations of the physical characteristics of precipitation during snow
events in the southern
|
Carroll, Turhan K. |
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Department(s): |
Applied Mathematics |
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Research |
Hien T.
Tran/Mathematics |
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Title of Presentation: |
Acoustic Pressure Waves in a Pipe |
Sound is a part of our everyday experience. As a
sound wave travels through a medium, it either reaches the end of the medium or
enters another medium through which it could travel. The interface of the two
media is referred to as the boundary. Understanding sound pressure waves and
corresponding boundary conditions is important for the proper operation of many
musical instruments and for the design of, for example, concert halls and
auditoriums. In this project, acoustic pressure waves in a PVC pipe were studied
using three types of physical boundary conditions: a hard plate, a soft foam
sponge, and no boundary. A different mathematical model was used to model each
of the boundary conditions. Acoustic data in a PVC pipe is being used to
validate the proposed mathematical models for the boundary conditions.
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Christoph, Elizabeth E. Hornsby, Fawn E. |
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Department(s): |
Statistics Statistics and Applied Math |
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Research |
William F. Hunt Jr./Statistics |
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Title of Presentation: |
Toxic Overload: Modeling Ambient Mercury Air
Pollution at a Trillionth of a Gram |
Mercury is a toxic pollutant that can cause adverse
health effects in humans through bioaccumulation in fish. It is released into
the atmosphere in several ways, most of which involve industrial processes. The
primary health effect of mercury is impaired neurological development. Impacts
on cognitive thinking, attention, memory, communication, and fine motor skills
have been seen in children exposed to mercury in the womb. Other effects of
elevated blood mercury levels include impaired vision, lack of coordination,
impaired speech, tremors, insomnia, muscle weakness, and even death. From the
atmosphere, mercury enters the water via wet and dry deposition where it
bio-accumulates in fish. Because of this concern, mercury air monitoring sites
were established in
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Diaz, Michael L. |
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Department(s): |
Marine, Earth, and Atmospheric Sciences |
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Research |
Ryan Boyles/Marine, Earth, and Atmospheric Sciences |
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Title of Presentation: |
Quality Control of Meteorological Data |
Accurate meteorological data are important in many
applications. However, the automated sensors which measure and record these data
occasionally provide inaccurate measurements. Therefore, in order for these
data to be useful, a “quality control” system to automatically identify
potential errors within large quantities of data is essential. The goal of this
project is to augment the climatological range check
quality control system of the State Climate Office of North Carolina with
another technique which attempts to locate erroneous data by examining the
spatial and temporal continuity of each recorded meteorological variable. For
each sensor, information from surrounding sensors is used to estimate the value
of each variable and its temporal rate of change using spatial interpolation
techniques. These calculated values are then compared to the measured values to
determine the likelihood that the measurements at a given sensor are accurate.
Specific policies to determine this likelihood must be fine-tuned such as to
minimize the number of “good” observations which fail the quality control and
the number of “bad” observations which pass it. Results indicate that a
combination of techniques using the difference between measured and
interpolated values, the number of standard deviations between the measured and
interpolated values, and the difference between measured and estimated rate of
change separate data by their likelihood of failure better than any single
technique. However, this quality control system has difficulty accounting for
localized effects of high elevation and proximity to the coast. Difficulties
also exist near the boundaries of the sensors’s
spatial domain, where spatial interpolation produces a strong bias toward the
region in the domain’s interior. Despite its shortcomings, this quality control
system will greatly improve quality control for the State Climate Office,
especially when used in conjunction with the already existing methods.
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Dixon, Anthony R. |
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Department(s): |
Mathematics |
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Research |
Hien T.
Tran/Mathematics Mette Olufsen/Mathematics |
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Title of Presentation: |
Mathematical Modeling of Cerebral Blood Flow
Dynamics |
Postural change is a common noninvasive procedure
used to study short-term regulation of the cardio-respiratory systems including
cerebral autoregulation, autonomic and respiratory
regulation. In subjects who suffer from orthostatic intolerance, postural
change is not well understood, and this work aims to validate a mathematical
model that can help describe this regulatory mechanism in more detail. Using a
three-element windkessel model, our primary goal is
to model the cerebral blood flow during a postural change. Finally, simulation
results will be presented depicting how well the mathematical model fit
experimental data.
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Drukenbrod, Joshua |
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Department(s): |
Statistics |
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Research |
William F. Hunt Jr./Environmental Statistics |
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Title of Presentation: |
Can Analysis of Public Data Bases Help Us Better Understand
the Reasons for Elevated Blood Lead Levels in Children? |
Within the past thirty years, there has been a vast
reduction in the concentration of lead found in our air, water, soil and homes;
however, toxic concentrations still exist and continue to affect our health. Is
there something researchers missed in the process? The removal of lead from
both lead and gasoline greatly reduced events of lead poisoning, yet
unacceptably high rates of lead poisoning still occur. The effects of lead
consumption are costly for both young and old; children may experience damage
to the brain and nervous system, learning problems, and slowed growth; adults
usually suffer from reproductive problems, high blood pressure and nerve
disorders, to name a few. This research uses exploratory analysis of multiple
databases such as the Toxic Release Inventory, air and water quality data, the
National Health and Nutrition Examination Survey (NHANES), Childhood Blood Lead
Surveillance Program (CBLS) and census data to gain a better understanding of
the lead problem affecting the children of our nation. The analyses presented
represent the first stage of research in a two semester project. The problem
was provided by our client; Dr. Barry Nussbaum of the U.S. Environmental
Protection Agency’s (USEPA’s) Office of Environmental
Information. The research objective is to locate the next major source of lead
contributing to elevated blood lead levels in
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Department(s): |
Statistics |
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Research |
Thomas Reiland/Statistics |
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Title of Presentation: |
Helping David Beat Goliath Again: Optimal Salary
Strategies for Small-Market Major League Baseball Teams |
Historically, baseball teams typically maximize
winning percentage by maximizing player salaries, attracting top talent for top
dollar. In order to remain competitive, small-market baseball teams must
allocate their limited resources more effectively than their “big-city”
counter-parts. Although increasing runs scored is an obvious strategy a team
can adopt to raise its winning percentage, the optimal implementation of this
strategy is not as clear when budgetary considerations are a significant
limiting factor. By examining both offensive statistics and salary data for all
Major League baseball players from 1995-2005 as well as offensive statistics
for Major League teams over the same period, this study developed three
empirical models aimed at simplifying this problem. The first model explains
observed team runs as a function of a linear combination of the numerators for
two widely used offensive statistics, slugging percentage and on-base
percentage. The second model relates a statistic created by the researchers as
a function of the same aforementioned numerators. This statistic, called “erg”
for “estimated runs generated” estimates the runs contributed by individual
players towards respective team totals. Significant results from analysis of
variance of both models suggests, first, that the slugging percentage and
on-base percentage numerators are useful predictors for team run production
and, second, that these same independent variables are also highly related to
our erg statistic. Finally, a third model relates individual player salaries to
a standardized transformation of the erg statistic. Due to substantial
variation in runs produced at any given salary point, LOESS smoothing is used
to better approximate the relationship between individual salary and individual
run production. Ideally, application of this model in allocating player
salaries will mitigate the competitive advantage enjoyed by teams with
substantially larger budgets.
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Hemperly, Joshua J. |
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Department(s): |
Marine, Earth, and Atmospheric Sciences |
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Research |
Ryan P. Boyles/Marine, Earth, and Atmospheric
Sciences |
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Title of Presentation: |
Estimating Daily Potential Evapotranspiration
across |
The United Nations Food and Agriculture Organization
(FAO) Penman-Monteith equation is a standard method
for estimating potential evapotranspiration. However,
critical measurements needed for input into the equation are not routinely
measured. The North Carolina Environment and Climate Observing Network (NC ECONet), maintained by the State Climate Office of North
Carolina, collects observations from sensors that provide all the needed
measurement to calculate FAO Penman-Monteith as well
as evaportranspiration estimated by atmometers. This presents a unique opportunity to use observations
to determine how well the FAO Penman-Monteith
performs when coupled with the Hargreaves or Angstrom short wave radiation
estimate equations. An accurate solar radiation estimate is important because
at other weather observing locations operated by National Weather Service and
the Department of Transportation there are no photovoltaic detectors, and thus
no solar radiation measurements. By finding an accurate way to estimate solar
radiation, the spatial and temporal representativeness
of the FAO Penman-Monteith equation is expanded, and
thus the potential for climatology of potential evapotranspiration
in
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Hoffman, Torissa J. Stevens, Derrick Ojha,
Satyajeet Sooryakant Mccullen,
Seth Roberts, Wes |
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Department(s): |
College of Physical and Mathematical Science,
Textile Engineering Chemistry and Science |
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Research |
Laura Clarke/Physics Russell Gorga/Textile
Engineering |
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Title of Presentation: |
Achieving Electrically Conductive Polymer Mats with
Minimal Doping by Tuning Fiber Morphology |
My project involves the developing of electrically conducting
scaffolds that could be used for tissue engineering where the conductivity of
the scaffold allows for the electrical stimulation of the cells. Electrically
conducting mats have a similar fiber size and porosity to a human’s extracellular matrix, which is coordinated with the growth,
repair and proper functions of tissue. These mats are conductive due to the
presence of conducting particles, such as multi-walled carbon nanotubes or silver nanoparticles,
within the polymer fibers, which make up the mat. The polymer/particle fibers
are created by a process called electrospinning (made
by collaborators in Gorga group). Most materials,
such as metals, are conductive because of properties of each of their atoms or
molecules. In contrast, our mats are a mixture of conducting particles and
insulating polymer. They become conductive when there is sufficient density of
particles so that the particles touch and form a path across the sample. As
physicists, we are interested in this fundamental process, which is called
percolation. In particular, our electrical measurements show that the
percolation threshold (the minimum amount of particle to achieve conductivity)
changes for different types of morphologies of the fibers in our mat. The three
different morphologies we have tested are a solid fiber, a core-sheath fiber,
and a film. From our data we have discovered that the percolation threshold of
the core-sheath fiber mat is lower than that of a solid fiber mat. In my
poster, I’ll discuss our hypotheses for this effect and our future work.
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Hopkins, Alyssa M. |
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Department(s): |
Marine, Earth and Atmospheric Science |
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Research |
Blake A. Schaeffer/Oceanography |
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Title of Presentation: |
Using Optical Techniques to Identify Case Waters in
the Galapagos Marine Reserve |
There are two major current systems that converge on
the Galápagos Marine Reserve (GMR); the Equatorial Undercurrent (EUC) and the
South Equatorial Current (SEC). As the Intertropical
Convergence Zone (ITCZ) migrates seasonally, different source waters supply the
SEC carrying optically unique constituents such as detritus and colored
dissolved organic matter (CDOM). Absorption of these constituents was derived
from remote sensing reflectance (Rrs), defined as the
ratio between upwelling and downwelling radiance at
the surface. Rrs was derived from a hyperspectral HyperSAS and
multi-spectral Moderate Resolution Imaging Spectroradiometer
(MODIS) Aqua satellite in March and November 2005. The HyperSAS
provided high precision hyperspectral measurements of
water-leaving sea surface reflectance while mounted onboard a ship. MODIS Aqua
satellite generated large scale 1 km resolution images of the GMR waters. The
Quasi-Analytical Algorithm (QAA) calculated absorption of phytoplankton and
detritus/CDOM from the Rrs. Pixels from MODIS that
corresponded with the latitude and longitude of the HyperSAS
measurements were used for satellite validation. Linear regressions identified
shipboard measurements were correlated with the satellite data. Absorption
contributions by phytoplankton and detritus/CDOM were identified. In the
future, multi-spectral (MODIS satellite) and hyperspectral
data collections will help track seasonal and inter-annual variability in the
water masses, which should prove invaluable in monitoring and managing the
ecological resources (fisheries and dive tourism) of the
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Hornsby, Fawn E. |
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Department(s): |
Statistics |
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Research |
Marcia Gumpertz/Diversity
and African American Affairs |
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Title of Presentation: |
How Missing Census Tract Information May Be
Associated With Early and Late Stage Breast Cancer in Addition to Other
Demographic Factors |
By modeling the proportion of cases of advanced
disease in a population group, we can provide insights into breast cancer
control strategies; however, when information about a patient is missing, that
patient is left out of the analysis. Census tract information can be linked to sociodemographic factors that would be helpful in
identifying subpopulations that would be at high risk for late stage breast
cancer. Out of a total of 26,565 cases, 747 were missing the tract identifier.
A logistic regression modeling the odds of advanced breast cancer by race was
fit to data from the 1990 decennial census data file and data from the SEER
program. The variables in the model included demographics such as age, marital
status, country of birth, year of diagnosis, census tract of residence, and
tumor biology variables. By examining which cases were missing the tract
information, we found that the odds of being diagnosed late stage disease
depended on whether their tract information was missing for certain racial
groups. For Asians, the odds of being diagnosed with late stage breast cancer
when missing the tract information are 2.73 times the odds if tract information
was present. Additionally, for the Black and White racial groups, the effect of
age is dependent on whether the tract information is missing. Despite these
findings, there does not seem to be a difference in the probability of late
stage diagnosis when cases had the tract compared with those that did not have
the tract information. Furthermore, a model was developed to determine the
factors associated with missing tract information. We found that birthplace,
reporting source, (hospital, lab, doctor’s office, autopsy, death certificate)
and year were significant predictors, while age, race, and marital status were
not.
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Lakhani, Amit M. |
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Department(s): |
Physics |
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Research |
Thomas P. Pearl/Physics |
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Title of Presentation: |
Investigation of Chiral
Thin Films of Tartaric Acid on Ag(111) |
The expression of chirality
in monolayer, molecular domains on surfaces has important implications for enantioselective catalysis and chemically tuned thin films.
The organizational structure of a chiral molecule,
tartaric acid (C4H6O6), weakly bound to an achiral
metal surface, Ag(111), has been studied with low temperature scanning
tunneling microscopy (STM) and low energy electron diffraction (LEED).
Molecularly resolved images of both (R, R)- and (S, S)- tartaric acid enantiomers on Ag(111) highlight the role of intermolecular
hydrogen bonding in stereospecific domain and superlattice formation. Proposed structures (as related to
adsorption geometry) have been determined from the experimental data for the enantiomerically pure thin films on the Ag(111) lattice.
Additionally, chiral domain formation and phase
separation from a racemic mixture of both tartaric
acid enantiomers has been studied. Finally, scanning
tunneling spectroscopy experiments have been used to confirm the weak binding
of tartaric acid to the metal surface.
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Landwehr, Justin G. |
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Department(s): |
Statistics Economics |
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Research |
Thomas Reiland/Statistics |
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Title of Presentation: |
Predicting Time to Next Foul in Basketball |
In basketball at any level, coaches inevitably must
decide whether to play or sit a player in foul trouble. Using data from the
National Basketball Association, we attempt to accurately predict a player’s
time to next foul using the gamma distribution and two simple statistics: total
fouls, and total minutes played.
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Miles, Travis N. |
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Department(s): |
Marine Earth and Atmospheric Sciences |
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Research |
Blake Schaeffer/Marine Earth and Atmospheric
Sciences |
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Title of Presentation: |
Relative Phytoplankton Concentrations During |
Discrimination of phytoplankton community composition
throughout the Galapagos Marine Reserve (GMR) is presented from a
state-of-the-art Optical Phytoplankton Discriminator (OPD) instrument. A single
absorbance signal exists for each phytoplankton pigment. Taxonomic groups of
phytoplankton have specific combinations of these pigments in the forms of
chlorophylls, carotenoids and phycobiliproteins.
This specific combination of pigments gives the taxonomic groups a
characteristic spectral signature. The spectra of in-situ samples identified
absorption bands of different pigments present in natural populations of
phytoplankton. Therefore, composition and dynamics of phytoplankton populations
were inherent to spectral data. The OPD generated surface spectral absorption
curves for phytoplankton composition differentiation throughout the GMR on two
field studies. The first cruise was June 2006 when the El Niño Southern
Oscillation conditions were relatively normal. The second cruise was November
2006 at beginning of a mild El Niño. El Niño produces abnormally warm
conditions in the equatorial Pacific and prevents the movement of nutrient-rich
subsurface waters to the surface that would occur under normal conditions. The
reduction in plant nutrients starves the entire ecosystem beginning with the
composition of phytoplankton and extending all the way to the top of the food
chain. On shorter time-scales, the GMR acts as a natural experiment for
measuring the effects of annual to inter-annual variability on flora and fauna.
We identify phytoplankton community composition changes between normal and El
Niño conditions.
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Onori, John E. |
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Department(s): |
Polymer and Color Chemistry |
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Research |
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. 125 ml flask
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 Waco DP 210. Both Inherent and
reduced viscosity agreed with each other. Future work will be to find intrinsic
viscosities of different types of celluloses.
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Pronschinske, Alex M. |
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Department(s): |
Physics |
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Research |
Thomas P. Pearl/Physics |
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Title of Presentation: |
Adsorption of 8CB Liquid Crystals on Poled, Lithium
Niobate (001) |
Extensive research has been done on the properties of
liquid crystals and ferroelectric materials separately that has led to
important applications, yet the two substances have not been studied in a
combined system. In our study we examine the wetting and ordering properties of
4'-octyl-4-biphenylcarbonitrile (8CB) liquid crystals on a ferroelectric (001)
cut lithium niobate (LN) surface. The single
crystalline LN samples are uniformly poled such that the two opposing faces of
the crystal along the z axis have equal charge densities but opposite polarity.
Due to the strong dipole moment of the 8CB liquid crystal we believe that the
molecule experiences a charged domain specific interaction with the LN surface
dictating the molecular alignment. We observe the surface characteristics of LN
and the wetting behavior of 8CB under different deposition times to gain
insight to the formation of the thin liquid crystal film, as low as a single
molecular layer. To do this we use a combination of surface sensitive tools
including atomic force microscopy (AFM), surface contact angle measurement,
X-ray photoelectron spectroscopy (XPS), and low energy electron diffraction
(LEED).
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Ribeill, Guilhem Sakon,
John J. |
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Department(s): |
Physics |
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Research |
Keith Weninger/Physics |
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Title of Presentation: |
Fluorescent Single Molecules Inside Cells |
Single molecule studies, such as those using
fluorescent techniques have seen increasing use in the investigation of the dynamics
of the cell. Toward this goal we have written custom software in MATLAB that
can track single particles from video fluorescence microscopy in living cells.
We have tested the software by locating and tracking fluorescent beads in vivo.
We are using SNARE proteins tagged with two fluorescent dyes in our efforts to
demonstrate the ability to detect FRET from individual proteins inside live
cells.
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Secreast, Sarah M. |
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Department(s): |
Marine, Earth, and Atmospheric Sciences |
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Research |
Anita McCulloch/Marine, Earth, and Atmospheric
Sciences |
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Title of Presentation: |
Distribution of Phytoplankton Populations in the
Surrounding Waters of the |
Many species of phytoplankton are an integral part of
the food chain. They can serve as the main primary producers of different water
systems, especially in oceanic systems. I conducted research on the different
species of phytoplankton in waters surrounding the Galapagos Islands,
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Speller, Danielle H. |
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Department(s): |
Physics |
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Research |
Gail McLaughlin/Physics |
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Title of Presentation: |
Predicting the Explosions of Stars |
One of the most
valuable systems in the study of stellar evolution and cosmological processes is
the supernova. Violent explosions of massive stars produce extraordinary
amounts of energy, particularly in the form of photons (light quanta) and
neutrinos (nearly massless elementary particles), and
are the birth place of most of the heavy elements required for life on earth.
Supernovae are rare events, and it is impossible to determine the exact time or
location, which is usually detected via the emitted light. We investigate a new
method of detection based on the principle that most large stars are cooled
primarily via the release of neutrinos, and these neutrinos are produced in
exceptional amounts right before the moment of star collapse. By detecting
these presupernova bursts, our efficiency of
observation and use of instrumentation will be greatly enhanced. Our research
focuses on the luminosity of the neutrinos and the likelihood of detection in
earthbound neutrino laboratories.
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Warren, Joshua |
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Department(s): |
Statistics |
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Research |
William F. Hunt Jr./Statistics |
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Title of Presentation: |
Understanding Historical Emission Trends |
Air pollution is harmful to people and the
environment. In order to better understand the nature of the environmental
problem, emission inventories are developed for all sources in an area. They
are based upon engineering estimates. They represent both gases and particles
of air pollution that are emitted into the air by a variety of sources.
Emission inventories (E/I) change over time and may be reduced as result of
emission control programs. The U. S. Environmental Protection Agency’s (USEPA)
Office of Air Quality Planning and Standards (OAQPS) is
responsible for the National Emissions Inventory (NEI). Emissions data are
collected by state, local, and tribal and the federal governments. The E/I
includes a number of different sources: (1) Point sources – stationary
locations of pollution include factories, pulp and paper mills, petroleum
refineries, electric power plants, etc.; (2) Mobile Sources - cars and trucks,
airplanes, etc.; (3) Biogenic sources – natural sources of emissions – trees,
animals, etc.; (4) Area Sources – small stationary source of emission such as
dry cleaners and degreasing operations. Future emissions are critically important
when trying to determine the impact of air quality standard regulations that
are protective of human health and the environment. How will regulations impact
sources in the future making changes needed to reduce emissions to achieve the
air quality standards? Emissions inventories are projected for future years to
conduct analyses for our rulemakings. The methods for forecasting emissions
into the future are complex. The objective of this project is to improve upon
the existing method to forecast future emissions. Two sectors will be examined
to forecast future emissions – petroleum refineries and chemical manufacturing.
The pollutant that will be examined is nitrogen oxides. We will try and take
technological change into account using gross domestic product and other
variables. The Presidents Energy Plan to reduce oil consumption by 20 percent
in 10 years will be used to forecast future emissions. Different alternatives
will be examined in the paper.
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Wilson-Short, Gareth B. |
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Department(s): |
Chemistry |
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Research |
Mike. H. Whangbo/Chemistry |
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Title of Presentation: |
Ab-Initio Study
of Magnetic Interactions in a Disordered Delafossite-Type
System |
The delafossite-type system
Ag2CuMnO4 displays crystalline disorder between Cu2+
and Mn4+, and the refined high-symmetry crystal structure does not
contain the expected (CuO6)10- Jahn-Teller
distortions. Ag2CuMnO4 exhibits high temperature
ferromagnetic properties arising from net magnetic moment in the
transition-metal-oxide layers. This moment is quenched at lower temperatures
due to antiferromagnetic order between layers [1].
This study seeks to address the possible origins of this net-moment by parameterizing a Heisenberg Hamiltonian (i.e. calculating
spin-exchange parameters) using the
[1] D. Muñoz-Rojas, et al
"Ag2CuMnO4: A new silver copper oxide with delafossite structure" J. Solid State Chem 179 (2006) 3883-3892
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Wootten, Adrienne M. Antczak George Harris, Jordan M. |
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Department(s): |
Marine Earth and Atmospheric Sciences, Statistics |
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Research |
William F. Hunt Jr./Statistics |
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Title of Presentation: |
Can Meteorologically Adjusted Ozone Air Quality
Trends Identify the Impact of the Presidential Nitrogen Oxide Reduction
Policy? |
Ozone trends
are often used to see the impacts of emissions control standards across the
country. These raw data trends are interlaced with the varying effects of
meteorology and thus difficult to draw sound conclusions upon. Many different
techniques have been created to counteract meteorology. The result of this
project is a time series model which removes the effects of meteorology along
with those of autocorrelation and leaves the true value of ozone concentration
before(pre-2003) and after the Presidential reduction policy. The model was developed
using ozone data and meteorological data from the Maryland Department of the
Environment. The data set used spans April through October of 1997-2006 for the
measuring sites in the states of
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Zapata, Cheryl L. |
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Department(s): |
Mathematics |
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Research |
Mette S. Olufsen/Mathematics C. T. Kelley/Mathematics Hien
Tran/Mathematics |
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Title of Presentation: |
Blood Pressure
and Blood Flow Variation during Postural Change from Sitting to Standing:
Model Reduction and Improvement |
Short term
cardiovascular responses to postural change from sitting to standing involve
complex interactions between the autonomic nervous system, which regulates
blood pressure, and cerebral autoregulation, which
maintains cerebral perfusion. We have developed a model which can predict
dynamic changes in beat-to-beat arterial blood pressure and middle cerebral
artery blood flow velocity during postural change from sitting to standing.
This model uses an electrical circuit analogy, predicting changes in blood
pressure (voltage) and blood flow (current) as functions of resistance and
compliance (capacitance). The base model has more than 100 parameters that must
be identified to predict regulatory response for individual subjects. In
preliminary work, an inverse least-squares problem was formulated to estimate
all 100 parameters to minimize the difference between observed data and
computed values. This optimization process is time-consuming and not feasible
if the model is to be validated against multiple datasets. In other preliminary
work on a 52 parameter steady state model, sensitivity analysis was used to
identify a small number (approximately 20) of sensitive parameters. We have
shown, using sensitivity analysis, that it is possible
to reduce the structure of that model and that with additional data it is
possible to identify more parameters. Sensitivity analysis is being use to
reduce the 100 parameter model to allow for a more efficient identification of
the model’s parameters and possible model reductions.
[ 2007 Undergraduate Research Symposium Main Page ]
Last modified February 2007 by Sharon E.
Hunt, WordHunting