Fourth Annual Sigma Xi Poster Session
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
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
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
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
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
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
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
Jaclyne Braiewa ’04, Michael Certo ’04, and Christopher Caspers ’04
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
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
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
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
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.
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).
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
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
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
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
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
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.