Fourth Annual Sigma Xi Poster Session
MacDonnell Atrium
Tracy
Adams ’04
Faculty Advisor: Dr. Dorothea Braginsky
The effects of different types of environmental information on
amount of items recycled
My experiment was an
attempt to see if I could manipulate the people's recycling habits by providing
participants with different types of information about the environment. Students, in the apartment complex on campus,
were exposed to one of the three independent variables: a fact sheet stating
the benefits of recycling, the fact sheet and the Motivation Towards the
Environment Scale, or the fact sheet and the New Ecological Paradigm Scale. The
dependent variable was the amount of recyclables recorded after the independent
variable was given compared to the number of recyclables recorded before the
experiment began. Participants were only given information so they could decide
whether or not to recycle for themselves because prior research has show behaviors
are more likely to continue if a person does so based on their own volition. It
was hypothesized the condition that received the MTES would have the largest
increase in the number of recyclables because it asks each participant to
assess personal reasons for engaging in
a pro-environmental behavior. This scale would require participants to think
about their own actions. The NEP
requires participants to indicate how strongly they agree or disagree with
statements regarding the relationship between humans and the environment.
Subjects were required to think about
how humans have affected the environment and not how their own actions do so.
The results of this
study were not significant. However, based on responses from the MTES and NEP,
participants recycle because they know it helps the environment and agree that
human activities are negatively affecting nature. This is interesting because
it shows people are aware of the environmental problems that face the world
today, yet do not recycle more. This indicates knowledge about what actions can
help the environment will not necessarily translate into individuals engaging
in environmentally beneficial behaviors.
The statistically non-significant results could also be due to the
length of the study or small number of participants in it.
Jamail
El-dean Ajaj ’04, John Eyzaguirre ’04, and Alfred Rossi ’04
Diets of three shallow-water fish in Long Island Sound: A
focus on Asian crab predation
This study examined the diets of three species of
nearshore fish (common mummichog, Fundulus heteroclitus, striped
mummichog, Fundulus majalis and cunner, Tautogolabrus adspersus)
from two sites in western Long Island Sound during the period
September-December 2003. All three
species are omnivorous, but the type and range of food items, consumed differed
among species. Fundulus heteroclitus
(N=232) had the most varied diet, consuming mainly green and brown algae,
arthropods (shrimp, amphipods, insect larvae, crabs), and polychaete worms,
whereas F. majalis (N=22) fed primarily on mollusks (Gemma gemma)
and green algae. The primary food items
found in the stomachs of T. adspersus (N=55) were algae and small
crustaceans, mostly amphipods, shrimp and crabs. Small Asian shore crabs (4-5 mm CW) were
found in 17% of the F. heteroclitus stomachs with food and 7% of the T.
adspersus stomachs. No Asian crabs
were found in any of the F. majalis stomachs analyzed. The only brachyurans found in the stomachs of
fish from these sites were Asian crabs.
This study represents the first documented account of predation by Fundulus
heteroclitus and Tautogolabrus adspersus on the recently-introduced
Asian shore crab, Hemigrapus sanguineus.
Juvenile Asian crabs may provide an important new food source for small
nearshore fishes as well as larger ones which forage in intertidal areas during
high tide. Further studies are needed to assess the importance of fish
predation in the regulation of Asian crab populations.
Necole Arrigio ’04, Jaclyne Braiewa ’04, Michael Certo ’04, and
Christopher Caspers ’04
Faculty
Identification of the Prdx6 Regulatory Elements that Control
Basal and Induced Transcription
Prdx 6 is a gene found
primarily in liver cells which functions to encodes an antioxidant protein from
the peroxiredoxin family. These antioxidant proteins are essential in reduction
of tissue damaging reactive oxygen species that are formed in the liver via
metabolic processes. It has been found that the Prdx6 protein may have a
protective effect on atherosclerosis in mice, and is a key line of defense in
mice exposed to oxidizing agents. Since transcriptional regulation of
antioxidants has recently been implicated in a number of diseases, the
transcriptional regulation of Prdx6 may be a common mechanism for its control,
and may have drastic effects on determining genetic susceptibility to the
disease. Prior studies from our lab
identified several putative transcription factor binding sites in the Prdx6
promoter, including an antioxidant response element (bound by Nrf2) and a
consensus site for the stress-response protein NF-kappa B. In order to investigate the regulatory
regions, 5’ deletion analysis was carried out. Four primers were designed to
correspond to regulatory regions upstream of the Prdx6 gene. The primers were
designed to contain 5’ restriction sites.
After PCR of these fragments, the products were cut by the corresponding
restriction enzymes and cloned into the pSEAP reporter construct. Once confirmed, the constructs were
transfected into murine hepatocyte cells and SEAP (alkaline phosphatase) levels
were measured.
The quantity of SEAP
produced by the different promoters represents the ability of each promoter
sequence to differentially drive transcription of the Prdx6 gene. This study will reveal those regulatory
elements that are required for both basal and induced transcription of Prdx6 in
liver.
Sarah Bachman ’05
Faculty
Rolled-leaf hispine herbivory of
heliconia spp. (Heliconiaceae) over an altitudinal gradient in
Hispine beetles (Coleoptera: Chrysomelidae, Hispinae) are
herbivores of the plant order Zingiberales (Strong 1977a). In the Monteverde area of
Aaron
Baker ’04
Faculty
Parental Job Status and the Development of Sexual Roles
With sample of 42 college-age students, this study looked
to establish a correlation between the development of classical sexual roles
and the job status of subjects’ parents.
Each subject was given a questionnaire asking personal information which
also included the BEM Sex Role Inventory.
Each subject’s parent’s jobs were rated by contemporaries for their
inherent masculinity (5), androgyny (3), and femininity (1). The difference between the father’s job score
and the mother’s job score were correlated with the difference in BEM scores of
masculinity and femininity. Significant
results were found that the jobs that parents have correlate with the
development of an adolescent’s classic sexual roles.
Marc
Bartman ’04, Corinne Clifford ’04, and Rob Keder ’04
Insights
into Animal Evolution: Hox Genes in Porifera
In contrast to some
well-known animal models, very little is known of the developmental control of
growth in sponges. This lack of information has limited our understanding of
important events in the course of animal evolution. The broad goal of this research is to
understand the genetic constituency of evolutionary important genes in sponge
development. Specifically, our research focuses on Hox genes.
Hox genes encode
transcription factors that orient a cell within three dimensional space and
determine its fate in terms of form and function. Expression of Hox genes
provides the basis for anterior-posterior axis specification throughout the
animal kingdom providing the enormous variations of morphological form
underlain by a common set of instructions (i.e. Hox gene clusters).
We used degenerate PCR
to isolate potential Hox
genes from three Poriferan genomes (Haliclona,Halichondria,
and Microciona). These sequences
fall into anterior, PG3 and central Hox
classes. (We have not yet identified a posterior class sequence.) Although
these sequences have been found we must show they are sponge specific and not
the sequences of sponge symbionts. We are currently testing these isolated
genes for sponge specificity by performing southern blot analysis.
Andrea Bazos ’04
Faculty
The Effect of Zinc
on Caspase 1 and 3 Activity in Apoptotic
Human Articular Chondrocytes
Apoptosis is a part of normal
growth and development of skeletal tissues. However, disregulation of this
process can lead to the onset of a number of degenerative diseases. Articular chondrocytes (AC) are the cells responsible
for the development and maintenance of joint tissue. The loss of cells from
joint tissue by apoptosis leads to development of arthritic lesions and damage
to the underlying bone. Metallothionein and zinc appears to buffer the effects
of oxidants produced during the apoptotic cascade and delay apoptosis. This study examined the relationship between pre-exposure to zinc
and apoptosis in cultured human AC. If metallothionein acts to delay apoptosis,
then increasing levels of metallothionein by exposing these cells to zinc would
make them more resistant to pro-apoptotic chemical agents. It was
expected that zinc treated cells would have lower levels of these apoptotic
enzymes. However, it appeared that Caspase 3 had a higher concentration in
cells treated with zinc as opposed to those with out zinc. Caspase 1 followed
our predictions and supports the original hypothesis. The difference in the two
enzyme assays may be due to their activation times in the apoptotic cascade, or
the age of the cells used for testing.
The data gathered from the caspase assays, appeared consistent with the
overall cellular protein and DNA data. The study provides evidence that prior exposure to Zn can influence apoptosis
in human ACs by modulating Caspase 1 and 3 activity. Further studies are required to determine the
mechanism of zinc’s influence on apoptosis in these cells.
Derek
Bickhart ’04
Faculty
Interrelation of Symbiotic Sponge Bacteria in
Chrondrilla nucula as shown through a 16S rRNA gene sequence comparison
The 16S rRNA gene can
serve as an important tool in determining the relationship of bacterial
species. As such, it was used in this
experiment to both identify and categorize bacterial symbionts of the
Sean Boyle ’05 and Cristina Worth ’05
Faculty
Do
During the summer season, lakes undergo a process of
succession in which a change in species composition is brought about by the
incremental replacement of one species by another. In eutrophic lakes, the
incremental replacement often leads to nuisance blooms of cyanobacteria. We
studied seasonal succession in phytoplankton and zooplankton communities in
The first step is to discern whether nutrient loading is
high.
Although
Jaclyne Braiewa ’04, Michael Certo ’04,
and Christopher Caspers ’04
Faculty
Investigation of Signal
Transduction Pathways That Regulate Prdx 6: A Peroxiredoxin Implicated as an
Atherosclerosis Resistance Candidate Gene in Mice
Cellular antioxidants include a group of proteins that
reduce and inactivate reactive oxygen species.
This inactivation is a defense mechanism that protects the cell from
oxidative stress generated during cellular processes such as inflammation,
wound repair, and growth. Peroxiredoxin
6 (Prdx6), the focus of our research, is a member of the recently discovered
thiol-specific antioxidant family. While
all the peroxiredoxins are highly evolutionarily conserved and are capable of
reducing hydrogen peroxide, Prdx6 is the most divergent member of the family
and an atherosclerosis-resistance candidate gene in mice. It has been previously demonstrated that the
gene is expressed in a variety of tissues, and exhibits a high expression in
both liver and lung. The transcriptional
regulation of antioxidant proteins is an important mode of control in stress
response. Prior studies from our lab
have identified multiple Prdx6 transcripts, and have demonstrated that Prdx6 is
transcriptionally down-regulated upon growth arrest, and transcriptionally
up-regulated in the presence of growth factors and oxidative stress inducing
agents. Based on the proposed mechanism
of action of these stimuli, our research sought to first, definitively confirm
that the multiple transcripts all correspond to Prdx6; second, determine the
time course of induction for each stimulus; and third, examine the role of
different signal transduction pathways in Prdx6 regulation. As a result of these experiments, we have
found three alternative transcripts associated with Prdx6, determined the rates
and patterns of gene induction and elucidated particular signaling pathways
induction and elucidated particular signaling pathways in the Prdx6 response to
growth factors and oxidative stress. These findings reveal new mechanisms of
control of this important antioxidant gene.
Kim
Carbone ’05
Faculty
An Exploration of
Matching Behavior in the Mouse
Research literature has
demonstrated that when choosing between response alternatives rewarded on
concurrent variable interval (VI) schedules, subjects tend to respond such that
the ratio of time invested on each option approximates the ratio of the incomes
received for those options. This
phenomenon is called matching and has been observed in numerous different
species. The present experiment investigates
the behavioral consequences of imposing a constraint on the standard matching
paradigm. This adaptation modifies the
VI schedule so that the timer for reward delivery on an option only runs when
the subject is investing time in that option. In other words, in order to
receive a reward, the subject must invest the amount of time set by the VI
schedule for a particular alternative. This constraint is intended to explore
alternative models of matching - one in which the subject adjusts its behavior
due to the return rates (reward per unit time invested) in a process called
melioration and another in which the subject matches as an a-priori strategy.
Christopher Chimera ’04
Faculty
The Mathematics of Blackjack
This research project is a mathematical analysis of the
game of blackjack. This goal is to
determine an optimal strategy for determining whether a player should hit,
stand, split a pair, or double down in each situation. A computer program was invented to consider
every possible hand in the game and determine to odds of success for each
possible choice in order to choose the best option.
Kathryn
Cole ’04
The Synthesis and Characterization of Goethite
Paragraph: Goethite is a major component of the soil. It
is an iron oxide responsible for the absorption of many soil contaminants,
including selenate (SeO42-), a mobile soil contaminant known to be toxic to
animals. The specific mechanisms of many of these absorptions are still
unknown. This project synthesizes goethite rather than directly collecting it
from the soil in order to study its fundamental properties and structure. The
samples will be characterized using X-Ray diffraction and solid-state NMR
techniques. A clear NMR spectrum of goethite has not yet been successfully
obtained and published; therefore, producing a clear spectrum will warrant
immediate publication.
Zachary Freedman ’05
Faculty
Aquatic Snails Benefit from Low Amounts of Heavy Metal
Pollution with Regard to Recruitment and Mass
A series of experiments were done to determine the effects
of low levels of heavy metal pollution on two species of snails. Physella columbiana is found mostly in polluted
lakes whereas Lymnea Palustris thrive in non-polluted lakes. Snails from the two species were collected
from reference lakes just west of
Sean Harrell ’04
Faculty
Advisor: Dr. Michael Brienza
Optical Heterodyning
on Diffuse Surfaces
Optical heterodyning is a technique in which two optical
waves of slightly different frequencies are combined to produce a wave with an
acoustic frequency. The experimental
apparatus is relatively basic; it is essentially an interferometer built with a
Helium Neon laser and geometric optics. By placing a moving diffuse target in
the path of the laser, the laser light will be Doppler shifted to a slightly
different frequency than the original beam.
When this signal is recombined with the base laser signal, a heterodyned
interference pattern will be produced.
This can be analyzed to give information about the motion of the
target. Current studies have focused
around the construction of such a device, and preliminary studies of its
operation.
Monet MacGillivray ’04 and Jessica
Michael ’04
Faculty
Investigations with
the DSC: Examining the Effects of Changing Rates of Heating for Sn-Pb Amalgams,
Polystyrene and Polymethylmethacrylate
For this research, the Differential Scanning Calorimeter
(DSC) was used to determine the eutectic points of the Sn-Pb amalgam and the
determination of glass transition temperatures for polystyrene and
polymethylmethacrylate, focusing on the effects of changing the rate of
heating. The accuracy and
reproducibility of the results from the Perkins DSC 7 in the Physical Chemistry
Laboratory was evaluated.
Jessica
Michael:
Various mole ratios ranging from 5%Sn-95%Pb to 85%Sn-15%Pb
were run at varying rates of heating and the changes in the Heat Flow v. Temp
graphs were analyzed. It was determined
that as the rate of heating is increased, the peak itself varies nearly
linearly the deviation from published values increase and the peaks become
broader as seen in the difference between onset and endpoint for the peak
(Delta C).
Monet
MacGillivray:
Polystyrene and
polymethylmethacrylate were run at varying rates of heating and the changes in the Heat Flow
v. Temp graphs were analyzed. With
increased rates of heating, there was a notable increase in the temperature at
which the Tg occurred and the height of stepped increase in the baseline was
larger.
Allison Michal ’04
Faculty
Apoptosis of Articular
Chondrocyte Cells
Apoptosis or cell death is a result of structural and morphological changes in the cell. Apoptosis is necessary for the body to maintain and develop homeostasis. It acts as a defense system for the body by removing dangerous or damaged cells. Improper activation of apoptosis, however, can have detrimental effects, such as the rapid destruction of T cells in AIDS patients. Apoptosis has also been associated with the early stages of osteoarthritis, which is responsible for the destruction of the cartilage tissue. Capsase enzymes activate the cell death process and these enzymes are themselves activated by cytochrome C oxidase. Metallothionein, which is produced by zinc, is thought to shield the role of oxidases in the body. By shielding the oxidative enzymes involved in the activation and enhancement of apoptosis, hopefully the effects of osteoarthritis can be reduced.
The purpose of this experiment was to examine apoptosis in cultured human articular chondrocyte cells using two different techniques. The first experiment verified the use of fluorescent microscopy to examine apoptosis and examined the effect of known pro-apoptotic reagents on articular chondrocyte cells.
The second experiment tested if zinc delayed or shielded
the effects of known pro-apoptotic reagents through its production of
metallothionein by assay analysis, including Caspase 3 activity, protein
concentration, and DNA concentration. The results of the experiment conclude
that apoptosis can be examined utilizing fluorescent microscopy and also to
distinguish the effects of pro-apoptotic reagents on articular chondrocyte
cells. It was also found that metallothionein production by zinc delays the
production of caspase 3 enzyme and thus, the subsequent effects of apoptosis.
However, further experiments need to be performed.
Marisa Osswalt ’04
Mentors:
Dr. April Hill & Dr. Malcolm Hill of Fairfield University and Dr. Markus
Noll & Dr. Werner Boll of the Institute for Molecular Biology,
Sponge PaxB shows ancestor gene had a Pax
Pax genes encode
transcription factors involved in embryonic development of the central nervous
system (CNS), organogenesis, and oncogenesis in complex metazoans. Members of the Pax gene family are
characterized by an evolutionary conserved paired domain sequence and presence/absence
of specific octapeptide and homeodomain sequences, all of which can be involved
in transcriptional activation or repression.
Pax genes have been grouped into 4 subfamilies (Pax A-D; corresponding
to Pax 1-9 in complex animals) based on these characteristics. Using degenerate PCR, we have identified a
Pax B gene in a marine sponge (Haliclona
loosanoffi). PaxB is the putative ancestor to all other Pax genes.
Furthermore, our results are the first evidence of a Pax 6-like homeodomain in
an organism lacking eyes. The Pax B subfamily corresponds to an ancient Pax
Eric Portante ’04 and Anthony Gadaleta ‘07
Faculty
Over the past three years, through the research with Dr.
Mike Brienza, I have helped develop new general physics lab experiments. The new labs focus on using human physiology
to teach physics. The purpose of this is
to create better understanding of the physics topics through a more interesting
experiment. There are a total of four
experiments that all have been tested with general physics lab students. These experiments are Pressures of the Human
Body, Center of Gravity of the Human Body, Auditory Localization, and
Properties of the Human Eye. Surveys on
the experiments have shown that students enjoy, understand, and retain the
experiments and the principles better than the classic physics experiments.
Current Contributors:
Sean Harrell ’04, Brendan Hermalyn ’07, and Anthony Gadaleta ’07
Past Contributors:
Rita Schneider ’05, John Eyzguirre ’04, and Serge Biryukov
Christy Trotter ’04
and Alan Ghaly ’04
Faculty
Effects of Zinc, Dexmetriazone, and T3 on chondrocyte proliferation and
differentiation
The goal of this research was to determine the optimal
growing conditions for chondrocytes based on the effects of zinc, Dexmetriazone
(Dex), and T3. Two mediums,
chondrocyte growth medium (CGM), and another containing chondrocyte
differentiation medium (CDF) were used as controls for adherent cells. The other four cultures grew in suspension in
CDF; zinc, Dex, T3 and a CDF suspension control (Susp). Cellular matrix proteins were determined by
gel electrophoresis; proteoglycan, alkaline phophatase, and protein
concentrations were determined by photometric methods. DNA content was gathered by fluorimetry. The data provided information regarding cell
proliferation and differentiation. The
data supports that CDF is necessary for the differentiation of cells and also
provides a more ideal environment. The
addition of T3, Zinc and Dex did not show any drastic improvement
upon these two factors. Combinations and
different concentrations of these additives may provide a better environment
than CDF alone.
Christopher Sullivan ’04, Garrick
Fearon ’04, and Ryan Metz ’04
Faculty
Vital Signs Baby Monitor
The purpose of the Vital Signs Baby Monitor project is to
create a fast, positive, and fail-safe means of monitoring breathing and pulse
in an infant. It is the hope of this
project that the device can reduce the number of cases of Sudden Infant Death
Syndrome (SIDS). The design calls for a
pulse oximetry system, a non-invasive means of monitoring blood oxygen levels
and pulse rate. This device will be
placed in a wrist strap on the infant that can be worn while awake or asleep
and will be powered by a small rechargeable battery. The device determines the level of blood
oxygen in the body by calculating the ratio of the red to infrared light
absorption that occurs in oxygenated and deoxygenated hemoglobin. It wirelessly transmits the data to a
wall-mounted unit in the guardian’s room that will create an audible alarm if
the vitals veer from the acceptable limits.
The wall mounted device features controls and an LCD screen and is
powered by 120 volts AC with a battery backup.
The end of the second semester of the senior project class will see the
completion of the prototype model.