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Abstracts from the 2002 Posters on the Hill section

Characterization of a Novel, Extracellular Catalase-Peroxidase from Enterohemorragic E. coli
Auburn University       Advisor: Douglas Goodwin       Student: Kristen Hertwig

Enterohemorrhagic Escherichia coli O157:H7 is a highly virulent and deadly foodborne pathogen that is particularly harmful to young children. Initially associated exclusively with contaminated ground beef products, E. coli O157:H7 outbreaks have now been associated with a wide variety of food and water sources, including municipal drinking water supplies. It is vital to understand the mechanisms that contribute to E. coli O157:H7 virulence so that strategies can be developed to control and prevent infection. Several proteins have been identified in E. coli O157:H7 that are absent from nonpathogenic E. coli strains, including an extracellular, heme-containing catalase-peroxidase (KatP). In order to initiate our evaluation of the role this enzyme plays in the E. coli O157:H7 virulence, we have cloned, overexpressed, purified, and characterized KatP. Visible absorption spectra recorded for purified KatP were consistent with spectra from other bacterial catalase-peroxidases. Likewise, the kcat for the catalase activity of KatP (7,500/s) was nearly identical to that observed for other similar enzymes. However, the Km of KatP for hydrogen peroxide was fivefold greater than that of other catalase-peroxidases. Stopped-flow kinetic analysis demonstrated that KatP rapidly decomposes peroxynitrite a highly bactericidal product of the human immune response. Although the results of our initial characterization indicate that KatP from E. coli O157:H7 is similar to other catalase-peroxidases, its presence in the extracellular environment combined with its ability to decompose peroxynitrite suggest that this enzyme may be part of a strategy to evade the host immune response and cause infection.

Environmental effects on drought tolerance in the common bean
Augustana College       Advisor: Steven Matzner       Student: Ellen Holste

Water deficiency is a major limiting factor in crop production. Global warming projections indicate many regions of the country are becoming warmer and drier; hence water deficiency may establish itself as an even a bigger problem. Understanding how water deficit affects plants and the mechanism plants have to tolerate this water stress will be critical if global warming projections prove true. The objective of this study was to examine the effects of various environmental factors on the resistance to blocked water conducting cells and drought tolerance in Phaseolus vulgaris (common bean). Beans were grown from seed in growth chambers and exposed to reduced moisture levels, reduced light levels, reduced phosphorus nutrition, or increased soil particle size compared with controls. A centrifuge was used to spin stem sections to specific tensions and measurements of hydraulic flow through the conducting cells were made. Low moisture, low light, and the larger soil particle size all increased drought tolerance. In contrast, low phosphorus nutrition decreased drought tolerance. The results of this study indicate that environmental factors can have a significant effect on the blockage of water conducting cells within a species; understanding the relationships between these factors and the resistance to blocked water conducting cells may enable us to predict and perhaps even manipulate drought tolerance in plants.

Literal Activation during the Temporal Processing of Metaphors
Augustana College, Rock Island       Advisor: Daniel Corts       Student: Daniel Fogerty

The role of literal meaning in metaphor comprehension is not understood or recognized, largely due to the lack of an adequate definition. Through defining and manipulating specific methodological components, direct study of literal activation during the time-course of figurative processing is possible. Results of this study suggest that literal meaning is activated in parallel with metaphor meaning during figurative processing, but different meanings are dominate at different times. Analysis of total time to participant response shows significant priming of literal meaning in literal contexts, but no activation in metaphorical contexts; mean trends in metaphorical contexts suggest possible deactivation of literal meaning following context presentations.

Distance-dependent effects on seed establishment of two neotropical palms
Barnard College       Advisor: Stephanie Pfirman       Student: Lisa Patrick

The high diversity of tropical trees has often been linked to their seed dispersal patterns, which may vary at different distances from the parent tree. This study investigated distance-dependent factors which influence seed establishment, such as patterns of seed movement, infestation, and predation. Ten fruiting individuals of each Welfia regia and Iriatea deltiodea were chosen as focal trees in old growth forest at La Selva Biological Station in Costa Rica. A total of 800 seeds were placed in protected and non-protected treatments both near and far from the parent tree, and examined over the course of seven weeks for movement, mammal predation, beetle infestation, mortality, and germination. Consistent with the Janzen-Connell hypothesis, more seed movement was found within 10 meters of the focal tree. Over the course of seven weeks, 53.8% of the seeds were moved from their original locations. Combined for both Iriatea and Welfia, approximately 10% of the total amount of seeds were moved by mammals more than once. Neither the presence nor the number of beetle holes was found to be significantly related to distance from the focal tree. However, beetle activity was related to the presence of a fungal pathogen. Overall, more Iriatea seeds died in the near plots as a result of insect infestation and mammal predation. Distance from the parent tree was not significantly related to seed germination. Perhaps differences in seed mortality and movement between species can be related to the dominance of these palms in La Selva.

Tyrosine283 Mutation of the Rat GnRH Receptor by Polymerase Chain Reaction
Barry University       Advisor: Gerhild Packert       Student: Maria Abreu

Gonadotropin-Releasing hormone (GnRH) is an essential reproductive stimulant in both males and females. This decapeptide particularly stimulates luteinizing hormone (LH) and follicle-stimulating hormone (FSH), which then stimulates gonadal secretion of testosterone, progesterone, and estrogen. The hypothalamus produces and secretes GnRH, which then binds to receptors on gonadotrophs. A comparative analysis of amino acid sequences among mammalian and nonmammalian GnRH receptors suggested that tyrosine283 located on the VI extracellular loop of the rat GnRH receptor is crucial for ligand binding affinity and signal transduction. Thus, we attempted to mutate the tyrosine283 on the rat GnRH receptor by using polymerase chain reaction (PCR). A primer set with the incorporated mutation was designed to perform PCR. Once we attained the full PCR product, we proceeded with several processes such as enzyme restriction digestion, ligation, transformation, and inoculation. We finally extracted the DNA by using the QIAGEN Plasmid MiniPrep kit. All our results were carefully checked by running a 1.2% agarose gel. The expected mutation of the wild type tyrosine283 into phenylalanine and leucine was successfully achieved. Based on our data, the coding region of the GnRH receptor gene was amplified by PCR and directly sequenced. Further studies on the consequences of this mutation will be conducted to elucidate differences of signaling pathways and ligand sensitivity among nonmammalian and mammalian GnRH receptors. Supported by NIH-FIC MIRT Grant, TW00033-09 Barry University and Chonnam National University

Origin of the 1974 Eruptions of Kilauea Volcano, Hawaii, by Magma-Mixing: Evidence from Mineral Chemistry and Crystal Size Distributions
Central Washington University       Advisor: Wendy Bohrson       Student: Bridget Diefenbach

Volcanic eruptions may be initiated when new magma intrudes (magma-recharge) and mixes with resident magma (magma-mixing) in a sub-volcanic magma chamber. In 1974, eruptions in July, September, and December occurred on Kilauea Volcano, Hawaii, producing three distinct lava flows. Previous work (Lockwood et al. 1999) suggests that the associated magmas were generated by a magma-mixing event. Mineral abundance and crystal size data from the 1974 lavas permit assessment of this hypothesis as well as quantification of the time between recharge and eruption. July lavas are characterized by abundant, large plagioclase, which commonly grows in the sub-volcanic magma chamber, and by crystal size data that suggest a residence time of ~12 years. December lavas are characterized by abundant, large olivine, which commonly grows at depth, and by crystal size data that suggest a residence time of only 1 year. September lavas exhibit intermediate characteristics. These data suggest that the July magma was stored in the sub-volcanic chamber for a period of years. Upon intrusion of new magma from depth, the July eruption was catalyzed and is dominated by this resident magma. A mixture of resident and newly intruded magmas was erupted in September, and finally the purest representation of the new magma was erupted in December. Based on the short crystal residence times, the time between intrusion of new magma and eruption was short (i.e. months). Similar studies at other volcanoes might allow estimates of the time between magma-recharge and eruption, and such quantification may lead to improved eruption prediction and hazard mitigation.

Effect of Immune System Activation on Conditioned Reinforcement
Concordia College       Advisor: Susan Larson       Student: Katie Richardson

Previous research has shown that immune activation can produce anhedonia, a decreased interest in pleasurable stimuli. Certain parallels have been made between the behavioral effects of the immune system, including anhedonia, and the behavioral changes and anhedonia found in depressed people. Understanding links between immune activity and depression may be helpful the minimization of the psychological symptoms that accompany illness. The present research attempts to develop a better understanding of these potential parallels using two behavioral paradigms designed to meausre conditioned reinforcement. In both a place preference and operant conditioning paradigm, the behavior maintained by conditioned reinforcement in male Wistar rats was examined to see if immune activity, induced by lipopolysaccharide (LPS), disrupted conditioned behavior. Preliminary results indicate that after an injection of LPS (75ug/kg), conditioned lever pressing in the operant paradigm was disrupted but the expression of a conditioned place preference was not. This suggests that the effect of immune activity on hedonic behavior depends upon the paradigm used for testing. Thus, the parallels between sickness and depression may be limited to the behavior being tested and the motivation for engaging in that behavior.

The effects of immune system activation on conditioned reinforcement
Concordia College       Advisor: Susan Larson       Student: Ostin Warren

Previous research has shown that immune activation can produce anhedonia, a decreased interest in pleasurable stimuli. Certain parallels have been made between the behavioral effects of the immune system, including anhedonia, and the behavioral changes and anhedonia found in depressed people. Understanding links between immune activity and depression may be helpful in the minimization of the psychological symptoms that accompany illness. The present research attempts to develop a better understanding of these potential parallels using two behavioral paradigms designed to measure conditioned reinforcement. In both a place preference and operant conditioning paradigm, the behavior maintained by conditioned reinforcement in male Wistar rats was examined to see if immune activity, induced by both lipopolysaccharide (LPS) disrupted conditioned behavior. Preliminary results indicate that after an injection of LPS (75mg/kg), conditioned lever pressing in the operant paradigm was disrupted but the expression of a conditioned place preference was not. This suggests that the effect of immune activity on hedonic behavior depends upon the paradigm used for testing. Thus, the parallels between sickness and depression may be limited to the behavior being tested and the motivation for engaging in that behavior.

Do sex-differences in strategy use place women at risk for lower performance in math and sciences?
Creighton University       Advisor: Isabelle Cherney       Student: Kate Rudersdorf

Despite the equivalent overall intellectual capacity of males and females, researchers have identified cognitive sex differences (Halpern, 2000; Maccoby & Jacklin, 1974). However, there is considerable controversy on the reasons for how, why, and when these differences emerge. There is also a lack of consensus regarding the role of biology, psychological factors (e.g., socialization, education), and methodology in the interpretation of results (e.g., McGivern, Huston, Byrd, King, Steele, & Reilly, 1997). Some researchers suggest that the inequities between the sexes might emerge during early childhood as a result of the formation of effective strategies (Campbell & Beaudry, 1998). Males tend to answer questions faster and take more risks when solving problems than females (Voyer, 1997). The purpose of this study was to identify the strategies men and women use to match lines from a comparison array and during mental rotation. Differences in mathematical background and college major were assessed according to strategy use and performance scores to see if they predicted test outcomes. Ninety-one men and 121 women completed the Judgment of Line Angle and Position Test (JLAP) and Mental Rotation Test (MRT). The results revealed significant sex differences, with men outperforming women in both tests. Men and women also tended to use different strategies to solve the JLAP. Only specific math classes predicted performance on the tests. The results suggest that differential use of strategies and mathematical background might place females at a disadvantage in solving cognitive tasks. These skills are particularly important for admission to dental, medical, and engineering programs.

Do sex-differences in strategy use place women at risk for lower performance in math and sciences?
Creighton University       Advisor: Isabelle Cherney       Student: Brandi McCulloch

Despite the equivalent overall intellectual capacity of males and females, researchers have identified cognitive sex differences (Halpern, 2000; Maccoby & Jacklin, 1974). However, there is considerable controversy on the reasons for how, why, and when these differences emerge. There is also a lack of consensus regarding the role of biology, psychological factors (e.g., socialization, education), and methodology in the interpretation of results (e.g., McGivern, Huston, Byrd, King, Steele, & Reilly, 1997). Some researchers suggest that the inequities between the sexes might emerge during early childhood as a result of the formation of effective strategies (Campbell & Beaudry, 1998). Males tend to answer questions faster and take more risks when solving problems than females (Voyer, 1997). The purpose of this study was to identify the strategies men and women use to match lines from a comparison array and during mental rotation. Differences in mathematical background and college major were assessed according to strategy use and performance scores to see if they predicted test outcomes. Ninety-one men and 121 women completed the Judgment of Line Angle and Position Test (JLAP) and Mental Rotation Test (MRT). The results revealed significant sex differences, with men outperforming women in both tests. Men and women also tended to use different strategies to solve the JLAP. Only specific math classes predicted performance on the tests. The results suggest that differential use of strategies and mathematical background might place females at a disadvantage in solving cognitive tasks. These skills are particularly important for admission to dental, medical, and engineering programs.

Do sex-differences in strategy use place women at risk for lower performance in math and sciences?
Creighton University       Advisor: Isabelle Cherney       Student: Lisa Susnjar

Despite the equivalent overall intellectual capacity of males and females, researchers have identified cognitive sex differences (Halpern, 2000; Maccoby & Jacklin, 1974). However, there is considerable controversy on the reasons for how, why, and when these differences emerge. There is also a lack of consensus regarding the role of biology, psychological factors (e.g., socialization, education), and methodology in the interpretation of results (e.g., McGivern, Huston, Byrd, King, Steele, & Reilly, 1997). Some researchers suggest that the inequities between the sexes might emerge during early childhood as a result of the formation of effective strategies (Campbell & Beaudry, 1998). Males tend to answer questions faster and take more risks when solving problems than females (Voyer, 1997). The purpose of this study was to identify the strategies men and women use to match lines from a comparison array and during mental rotation. Differences in mathematical background and college major were assessed according to strategy use and performance scores to see if they predicted test outcomes. Ninety-one men and 121 women completed the Judgment of Line Angle and Position Test (JLAP) and Mental Rotation Test (MRT). The results revealed significant sex differences, with men outperforming women in both tests. Men and women also tended to use different strategies to solve the JLAP. Only specific math classes predicted performance on the tests. The results suggest that differential use of strategies and mathematical background might place females at a disadvantage in solving cognitive tasks. These skills are particularly important for admission to dental, medical, and engineering programs.

STUDY OF SV40 INFECTIOUS VIRION FORMATION IN THE ABSENCE OF VP2, VP3 AND BOTH VP2/VP3 STRUCTURAL GENES USING CV-1 MONKEY CELL LINE
CSULB       Advisor: Editte Gharakhanian       Student: Luz Munoz

Simian Virus (SV40) is a small double stranded circular DNA virus, and recent studies have indicated it to be a potential vector for gene therapy. Thus, studies of SV40 infectious particle formation are key in developing SV40 as a vector for gene therapy. SV40 is composed of three structural proteins Vp1, Vp2 and Vp3, which are synthesized in host cytoplasm during late permissive infection. Vp1 is the major structural protein of SV40. Vp2 and Vp3 are minor proteins that also take part in viral capsid formation. It is not known whether Vp2 and Vp3 play roles in the formation of infectious virions. To address that, site directed mutagenesis was used to create point mutations in the SV40 genome, changing start codons of Vp2 and Vp3 to stop codons. Mutants would eliminate the expression of Vp2 and Vp3 genes and would allow for the studies of nuclear transport and virion formation in the absence of DVp2, DVp3 and both DVp2/Vp3. Formation of infectious virions was determined by plaque assays following cationic lipid transient transfection of CV-1 monkey cell lines with SV40 mutant DNA. Infectious virions were only observed in SV40 wild type and DVp2 mutant transfected cells indicating that the Vp3 minor protein is crucial to the formation of infectious SV40 virions. Suggesting that the Vp2 gene is not necessary in capsid formation and can be exchanged for foreign DNA in gene therapy.

Electrophysiological Analysis of the Crossed Temporodentate Pathway in an Animal Model of Alzheimer's Disease
Davidson College       Advisor: Julio Ramirez       Student: Stephanie Courchesne

Alzheimer’s disease is a neurodegenerative disorder, characterized by neurofibrillary tangles and plaques, that causes progressive memory loss, altered emotional status, and eventually death. In its early stages, the pathology preferentially occurs in the hippocampal formation, an area of the brain important for learning and memory. This pathology disconnects the hippocampus from the neocortex by injuring the entorhinal cortex. In rats, unilateral destruction of the entorhinal cortex and consequent degeneration of the perforant path to the hippocampus results in transient impairments in working memory tasks, with behavioral recovery occurring after approximately eight days. In response to entorhinal damage, neural reorganization occurs within the hippocampal system. This remodeling, or sprouting response, involves the proliferation of other pathways to the hippocampus, including the crossed temporodentate pathway (CTD). Originating in the undamaged entorhinal cortex, the sprouted CTD shares many functional characteristics with the perforant pathway and is implicated in behavioral recovery. Previous studies have shown that CTD proliferation and the formation of functional connections are identical to the time course of behavioral recovery. As the CTD sprouts, it shows electrophysiological properties similar to the perforant pathway. The present study has demonstrated that the acceleration of CTD sprouting enhances short-term synaptic events that may contribute to learning and memory. As these changes in neural connectivity may mediate behavioral recovery in memory tasks, it is conceivable that harnessing this sprouting response in Alzheimer’s disease could lead to the development of therapeutic interventions.

NOVEL MATERIALS FOR HEAT-BASED SOLAR CELLS
Davidson College       Advisor: Tim Gfroerer       Student: Lynn Priestley

NOVEL MATERIALS FOR HEAT-BASED SOLAR CELLS L. P. Priestley and T. H. Gfroerer, Davidson College, Davidson, NC M. F. Fairley, Spelman College, Atlanta, GA M. W. Wanlass, National Renewable Energy Laboratory, Golden, CO In collaboration with crystal growers at the National Renewable Energy Laboratory, we are studying a set of materials that may be useful for a promising new technology called thermophotovoltaics. Thermophotovoltaic cells are similar to solar cells, but they convert radiant heat (rather than light) into electricity. To optimize the efficiency of these devices, we seek to decrease the threshold energy for absorption so that more radiant heat is absorbed in the cell. In the particular material that we are investigating, Indium Gallium Arsenide (InGaAs), the threshold energy can be reduced by increasing the ratio of Indium atoms to Gallium atoms. However, changing this ratio produces a difference in atomic spacing between the InGaAs and the underlying substrate material, which is required for crystal growth. This difference (called lattice mismatch) leads to the formation of defects, which usually has a deleterious effect on the fate of heat-generated excitations in the cell. Ideally, all heat-generated excitations are swept out of the cell by an internal electric field, producing electricity. In reality, the excitations can be lost by a variety of mechanisms during their brief residence in the cell. We have studied the optical properties of InGaAs as a function of the Indium-to-Gallium ratio in order to gauge how lattice mismatch and other fundamental properties associated with the InGaAs material affect these mechanisms. Ultimately, our work should facilitate the design of more efficient thermophotovoltaic cells.

N-Nitrosation of Pyrrolizidine Alkaloids-A Mutagenic Pathway Rebecca Leonard (Anusree Ganguly), Department of Natural Science, Dominican University of California, San Rafael, California 94901
Dominican University of California       Advisor: Anusree Ganguly       Student: Rebecca Marie Leonard

The purpose of this research is to synthesize and conduct mutagenicity tests on N-nitrosation products of Pyrrolizidine Alkaloids (PAs). PAs are plants of herbacious origin and occur in many parts of the world in unrelated botanical families and genera. These plants are known to be associated with livestock losses due to liver or lung lesions as well as cause human death due to primary liver cancer . The testing of pure PAs for carcenogenicity has not been extensive. The acute toxicity of these alkaloids has been established due to their in vivo oxidation to pyrrolic intermediates, however, research literature indicates that in either the Ames test or in E. coli test systems these PAs signal no mutagenicity (or in a few isolated cases very weak mutagenicity). Our research project probes an alternate pathway for the mechanism of the cancer causing ability of these alkaloids that of endogeneous nitrosation to form mutagenic nitrosamines which are known to have specificity towards liver tissues. Studies on the formation of nitrosamines via the N-nitrosation of PAs under endogenous conditions of NaNO2/HCl are reported. The N-nitrosation reactions were monitored by reverse phase TLC. Nitrosamine products identified by UV visualization and Griess reagent. The products were subjected to the Ames mutagenicity test. The Ames test results of the parent PA compared with the nitrosamine derivatives gives us an insight of the actual mode of action of the PA's.This research will help answer questions to the fundamental cause of mutagenicity and mode of action of these PAs.

MOLECULAR SIMULATIONS OF NOVEL HIV PROTEASE INHIBITORS Julia James* and Carol Parish, Department of Chemistry, Hobart & William Smith Colleges, Geneva, NY 14456
Hobart and William Smith Colleges       Advisor: Carol Parish       Student: Julia James

The replication of the virus that causes the autoimmune deficiency disease (AIDS) is controlled by the HIV protease enzyme. The HIV protease is a basket shaped molecule which functions in the viral pathway by clipping longer pre-viral chains into smaller segments that go on to reproduce the virus. Protease inhibitors occupy the active site, interfering with the functioning of the enzyme and halting the maturation of the virus. Molecules that inhibit the function of this enzyme have potential as important therapeutic agents. This work will investigate various FDA-approved HIV protease inhibitor drugs using molecular modeling methods to identify similarities and differences in the way these drugs interact with the protease active site. For instance, functional group interactions and conformational flexibility are thought to be extremely important in the binding of the inhibitor to the protease. Models have been proposed for specific inhibitor-protease interactions; however there has not been a systematic comparison of known inhibitors. Conformational search results will be used to answer the following questions: What common structural motifs do active inhibitors share? Are hydrogen-bonding patterns the same among all inhibitors or unique to individual inhibitors? Do active inhibitors share similar conformational behavior? What role do solvent interactions play? The MacroModel molecular modeling software will be used to characterize the conformational behavior of FDA approved inhibitors. Molecular mechanics are force field based and capable of evaluating the conformational flexibility of molecular systems. Conformational analysis will include solvation effects using the GB/SA continuum solvent model for water. Conformational flexibility will be studied using Monte Carlo and Low-Mode conformational search techniques. These methods randomly sample different locations on the potential energy surface of the complex. This allows efficient identification of all local minimum energy conformations. Examination of the number and diversity of local minimum conformations provides a picture of the molecular flexibility and behavior of the inhibitor. J.J. thanks the American Chemical Society Scholars program for an undergraduate fellowship. Partial support of this research by the American Chemical Society-Petroleum Research Fund and the Jesse B. Coxe Foundation are gratefully acknowledged.

Geologic History of the Dune Complex Along the Southeastern Shore of Lake Michigan
Hope College Geology Department       Advisor: Edward Hansen       Student: Brian Yurk

The dune complex on the eastern shore of Lake Michigan is one of the largest freshwater dune complexes in the world. The dunes are an important aesthetic, recreational, and economic resource for the region. The study of their natural history is essential to their proper management. Based on radiocarbon dates from buried soils, the dunes on the southeastern shore of Lake Michigan began forming between 6500 and 5500 years ago. Most early dune growth occurred between 4500 and 3300 years ago, after which growth tapered off as the dunes entered an extended period of stability with very little growth or migration. Dune activity began increasing again 1000 years ago and has accelerated significantly in the last 500 years. A detailed analysis of the natural history of one parabolic dune in Holland, Michigan includes the combination of data from radiocarbon dates, internal dune structures, and contemporary measurements of sand transport, topographic changes, and wind flow patterns. A radiocarbon date on a buried soil indicates that the average dune migration rate over the last 300 years has been 26 inches per year while aerial photographs indicate an average rate of 41 inches per year over the last 60 years. Dune migration occurs mostly as the result of high-energy windstorms. In a recent storm more sand was deposited on the back slope of the dune than was deposited during the 2 months preceding the storm. Contemporary sand transport measurements indicate dune movement occurs primarily at the leeward nose of the dune.

Constituents of Runoff from Environmental Surfaces
Immaculata College       Advisor: Carl Pratt       Student: Han Tran

Precipitation is typically intercepted by a variety of environmental surfaces. These surfaces include streets, highways, roofs, sidewalks, etc. Pollutants emitted into the atmosphere will often be carried by the precipitation and, once the precipitation contacts a surface, an exchange can occur with the result being a potential source of pollutants that can enter storm drains and ultimately end-up in surface waterways or groundwater. Increased land development results in increased impervious surfaces which in turn result in increased potential contribution of pollutants. Thus, we believe the potential contribution of pollutants by impermeable surfaces is crucial to understanding the potential contamination of waterways and groundwater. This investigation focuses on the roof surfaces of rural and urban homes. Our analysis examined: Al3+, Cl-, Cl2, Cu, Fe, Ni, NO3-, PO42-, SO42-, Zn, pH, turbidity, conductivity, and phenol content of rainfall and water collected as runoff from roofs. All data were subjected to one way ANOVA or student's t-test. Initial results show significant differences (P < 0.05) among rainfall, rural and urban roof runoff for a number of the parameters monitored. In general, there were significantly elevated concentrations (ppm) of Al3+, Cl-,Cu, Fe, Ni, NO3-, PO42-, SO42- in both roof samples as compared to rainwater and higher levels of these materials in urban vs. rural samples. Turbidity also showed significant differences among the sample sites: rainwater having the lowest turbidity (2.32 + 0.10 NTU) and rural roof (2.98 + 0.28 NTU) and urban roof being the highest (4.22 + 0.19 NTU).

Surface Modification of Indium Tin Oxide Using Carboxylic and Phosphonic Acid Self-Assembling Systems
James Madison University       Advisor: Wm. Christopher Hughes       Student: Sharon Koh

Indium Tin Oxide (ITO) can be used in biosensors, solar cells, organic light-emitting diodes, and for other electronic and industrial applications. Charge injection in the contacts on ITO-based devices has been difficult due to the energy barrier between the ITO contacts to an organic hole transport layer, which can be decreased by increasing the work function of ITO. This can be achieved by modifying the surface of ITO using self- assembled monolayers. Self-assemblying molecules with dipole moments can change the work function of ITO. Carboxylic and phosphonic acid self-assembly systems were studied to modify ITO and other metal oxide surfaces. Clean substrates are important to monolayer formation; therefore standard degreasing methods, plasma cleaning methods, and a wet cleaning procedure were explored. Contact angle measurements and x-ray photoelectron spectroscopy were used to characterize clean and treated substrates. It was shown that phosphonic acid self-assembly systems formed better monolayers on ITO then the carboxylic acid self-assembly systems. It was also discovered that the ITO modified by nitro- and cyano-phenyl-phosphonic acid systems changed the work function of ITO as verified by Kelvin probe measurements.

"Passivation of PCR Chamber for Use in Microchip Separations"
James Madison University       Advisor: Brian Augustine       Student: Joy Polefrone

Microchip technology has allowed for the miniaturization of various analytical processes onto a microchip format. Polymerase chain reaction (PCR) is one of the technologies that have been reproduced in the microchip format. Currently, several challenges remain for developing high efficiency PCR in a microchip. Taq polymerase, the enzyme necessary for PCR, readily absorbs to the glass surfaces, making it necessary for the glass substrate to be pretreated or altered in order to deter adhesion and allow for successful amplification. Polyimide has been used successfully as a substrate for PCR on a microchip, yet it is not an ideal substrate for the other analytical processes (i.e. separations) on microchips. In order to integrate these processes onto a single microchip, it is necessary to create a hybrid chip to couple the positive properties of both polyimide and glass materials. This work explores the use of a polyimide resin coating of glass PCR microstructures as a way to successfully passivate the glass surface, yet allow for other analytical functionality on a single device.

"Quanititative Determination of the Thermodynamic Equilibrium Constant for the Interaction of IRP1 and IRE."
John Carroll University       Advisor: David Mascotti       Student: Laureen Lenchak

The synthesis of a number of genes important for iron metabolism is regulated by the reversible interaction of Iron Responsive Proteins (IRP1 and IRP2) with Iron Responsive Elements (IREs). The conserved IREs are stem-loop structures found within the mRNA of these genes. The affinities of the IRPs for different IREs have been measured qualitatively, but limited quantitative data exists. Where such data is available, there are considerable discrepancies between different laboratories. For instance, the reported Kd for IRP1 binding to the IRE found in ferritin ranges from 60 pM to 80 nM. Thus, the goal of this project is to determine if bandshift assays can be used as quantitative reporters of binding affinity, and if so, quantitatively measure IRP1-IRE affinities. Preliminary evidence suggests that IRP1-IRE complexes dissociate during agarose gel electrophoretic mobility shift assays (EMSAs). Therefore, thermodynamic binding data obtained from EMSAs are likely to be unreliable, casting some doubt on previously published binding affinities.

THE ROLE OF SIR4 IN HIGH TEMPERATURE TRANSPOSITION OF THE TY1 RETROELEMENT
Juniata College       Advisor: Jill Keeney       Student: Meredith Boyle

Retrotransposons, such as the Ty1 element in the yeast Saccharomyces cerevisiae, resemble retroviruses in both their structural components and mechanism of transposition. Transposition of Ty1 is at its highest levels at approximately 24°C and decreases at higher temperatures until it is abolished above temperatures of approximately 33-35°C. Mutants maintaining the ability to transpose at high temperature were selected. The mutant gene allowing for high temperature transposition was cloned and identified as SIR4. SIR4 is a Silent Information Regulator whose protein product is part of a complex that is integral to transcriptionally silenced regions of chromatin, such as the yeast mating loci (MAT) and telomeres. SIR4 is also involved in cellular aging processes. It is unknown whether high temperature transposition in SIR4 mutants is related to these functions, or to a novel function. This research details aspects of the molecular mechanism by which SIR4 mutants allow for transposition of Ty1 at high temperatures. It is likely that information about the mechanism of transposition in Ty1 can be applied to the retroviral mechanism of transposition. Information of this type is extremely useful to areas of biomedical research concerning treatment and inhibition of retroviruses.

A Functional Analysis of Dirofilaria immitis Nuclear Receptor Di-NHR-6-- a Possible Role in Molting
Loyola College, MD       Advisor: Kirsten Crossgrove       Student: Maureen Luschini

Filarial parasites cause many debilitating diseases in both humans and animals. Once transmitted to their vertebrate hosts through an arthropod vector, these parasites continue to develop to the adult stage and may produce offspring, further continuing the cycle of disease transmission. Understanding how these nematodes develop as well as what type of environmental cues and/or biochemical mechanisms control and regulate their growth can provide key insight for drug intervention of filarial diseases and parasite control. In this study we investigate a possible biochemical mechanism of development within the filarial parasite Dirofilaria immitis, the causative agent of canine heartworm disease. We propose that the D. immitis nuclear receptor (NR) Di-NHR-6 regulates the L3 to L4 molt of this parasite based on its homology to the Drosophila E75 nuclear receptor, a NR observed to be involved in molting and metamorphosis through sequence specific DNA binding. In order to investigate the DNA binding properties of Di-NHR-6, we have generated two cDNA constructs of this gene, both of which contain the DNA binding domain. Having optimized the conditions for a non-radioactive DNA binding assay, we will use the proteins encoded by these constructs to analyze Di-NHR-6 DNA binding activity.

Unintentional Intelligence Stereotypes
Lynchburg College       Advisor: Madeline Fugere       Student: Christina Conlon

Most people are unwilling to express prejudices and stereotypes, although they may harbor these feelings. The Implicit Association Test (IAT, Greenwald et al., 1998) provides an alternative to explicit prejudice and stereotype measurement by examining response latencies. For example, the IAT measures outgroup prejudice by requiring participants to pair names of ingroup and outgroup members with positive and negative words as quickly as possible. Research using the IAT has revealed outgroup prejudice and implicit (unintentional) stereotypes. The present research is the first to examine the IAT’s effectiveness as a tool for measuring implicit intelligence stereotypes. We modified the IAT so that the participants paired names of ingroup and outgroup members with “intelligent” and “unintelligent” words. Participants were presented with either African, Chinese, or Hispanic American (outgroup) names and White (ingroup) names on a computer screen. Participants were also presented with “intelligent” and “unintelligent” words. On some trials, ingroup names and “intelligent” words shared a response key and on other trials outgroup names and “intelligent” words shared a response key. Our results suggest that participants do hold unintentional intelligence stereotypes. We found that participants paired ingroup names with “intelligent” words significantly more quickly than outgroup names with “intelligent” words. While more research regarding stereotypes about different ethnic groups is necessary, the current study demonstrates the presence of automatic intelligence stereotypes. This research exposes potential barriers to the equal treatment of members of different ethnic groups and should be noted as efforts to eliminate affirmative action arise (e.g. Proposition 209 in California).

High-resolution electrical resistivity measurements as a geophysical tool on East Antarctic Holocene ocean sediments
Middlebury College       Advisor: Patricia Manley       Student: Katharine Burgdorff

The Holocene (last 10,000 years) has been a focus in climate change research as more and more abrupt changes are revealed in terrestrial, ice and marine sediment cores around the world. The polar regions have proven to be environments that are very sensitive to small climate changes. For this reason, the objective of this study is to look at high-resolution detailed records in marine sediments for climate cycles. Sediment cores were obtained along the eastern margin of Antarctica (147°E to 57°E) from January to March, 2001 aboard the Nathaniel B. Palmer. Our data set includes 29 Kasten cores (3m-long gravity cores) with electrical resistivity (ER) measured in ohm-m every 2cm downcore. Analyzing core photos, core descriptions, physical property data and electrical resistivity, the results show a strong linear negative correlation between electrical resistivity and porosity. On plots of ER vs porosity we observe that the differing lithologies of the cores are well delineated. Laminated diatom oozes have generally low resistivities and high porosities whereas diatomaceous clays and muds have higher resistivity values and lower porosities. This is further confirmed in the ER vs void ratio plots. Void ratio (related to porosity) and ER measurements are sensitive to differing diatom assemblages, e.g. Thalassiothrix. High-resolution resistivity measurements can act as a proxy to quickly identify subtle lithology changes downcore in addition to assessing the amount of biogenic silica in the sediment, aiding future researchers in climate change studies.

Real-time Dyanmics Modeling of a Nanosatellite's Micro Thruster.
NASA Goddard Space Flight Center       Advisor: Thomas Correll       Student: Aron Cooper

Satellites have become an integral part of today’s world; they not only have an immediate effect on our everyday lives by improving our abilities in communication, safety, and national security, but also influence our future by helping scientists to better understand the world we live in. In an effort to drastically improve current satellite technologies NASA’s New Millennium Program is developing a group of three nanosatellites called Space Technology 5 (ST5). This mission will test a number of new technologies that, once proven, will make it possible to produce satellites that are smaller, lighter, cheaper, and more efficient. One of the most important aspects of developing a new spacecraft is ensuring there is an accurate way to test how different parts will react to different situations and how they will affect the mission of the spacecraft. During my participation in the NASA-Undergraduate Student Research Program (USRP) I have assisted my mentor, Thomas Correll, in the development of a dynamic simulator for the ST5 mission. This simulator will imitate the flight and attitude dynamics of ST5 based on commands it receives from the flight software that is being tested. In order to develop this type of simulator it is necessary to develop accurate models for the actuators and sensors the spacecraft will be using. My primary task has been to develop an accurate real-time dynamics model of the spacecraft’s micro thruster, one of the new technologies being developed and tested on ST5. This includes modeling the Thruster Control Electronics, thruster valve response, propellant state, and the influence the thruster has on the spacecraft’s flight and attitude dynamics. This model has thus far been shown to be accurate while running as a part of a, primarily pre-existing, multi-threaded program.

DENSE NON AQUEOUS PHASE LIQUIDS: SITE CHARACTERIZATION TECHNIQUES FOR TRICHLOROETHYLENE
National Aeronautics and Space Administration       Advisor: Jacqueline Quinn       Student: Julie Litzenberger

Dense Non Aqueous Phase Liquids (DNAPL) can be difficult to detect and analyze in the subsurface. They frequently pose a public health concern and require removal and treatment to ensure public safety. Specifically, the behavior and detection of the chlorinated solvent trichloroethylene (TCE) was examined. TCE exhibits chemical behavior that makes it difficult to detect in subsurface areas. A site-specific evaluation of Launch Complex 34 at Cape Canaveral Air Force Station in Florida was used to analyze existing site characterization technologies. Site characterization techniques addressed include methanol extraction, soil gas surveys, partitioning interwell tracer tests, cone penetrometer tests, and the FLUTe membrane method. The proper detection of DNAPL contamination is essential to preserving the integrity of human life and the environment.

Simultaneous Evershed Flow Velocity Measurements of the Solar Chromosphere and Photosphere
National Solar Observatory       Advisor: Matthew Penn       Student: Jose A. Ceja

The study of sunspots is of great importance in developing a magnetic field model for the Sun. Sunspots are cool areas of the Sun where magnetic filed lines concentrate. Sunspots consist of a dark central area (the umbra) and a lighter area surrounding it (the penumbra). Magnetic field lines travel in and out of the surface of the Sun in the umbra and radial towards or away from the sunspot’s center in the penumbra. The subject of this study is to measure the velocity of the radial flow of matter in the penumbra. The velocity of this phenomenon, known as the Evershed flow, was measured simultaneously in the chromosphere and photosphere using the He I 1083.03 nm and Si I 1082.71 nm spectral lines respectively. Results show consistent behavior, reveal that Evershed flow velocity can be up to nine times greater in the chromosphere than in the photosphere, and quantify these velocities for the first time.

Phosphotransfer Dynamics Rather Than Adenine Nucleotide Pools Secure Functional Recovery in Adenylate Kinase AK1-knockout Heart
North Central College       Advisor: Steve Johnston       Student: Lynette Lim

The two major forms of heart diseases, ischemic heart disease and heart failure, are states of compromised energetic. In cardiac bio-energetic, ATP is generated in the mitochondria and utilized for generating mechanical work by the myofibrils. It is believed that efficient ATP transferred is accomplished by phosphotransfer enzymes composing of the creatine kinases system (CK), adenylate kinases (AK), and glycolytic enzymes. Using 18O isotope-labeling methods, we found that transgenic mice with AK-1 knockouts reduce total AK activity by 94%. Decrease of AK phosphotransfer flux in AK1-knockout was less dramatic to 41 ± 15 % relative to wild type due to functional reserve of the minor AK isoforms - AK2 and AK3. AK1-KO has glycolytic compensation shown by a significantly higher level of G6P. While AK1-KO also showed significantly lowered adenine nucleotide pools, recovery of AK1-KO hearts was not different from wild type, before and after ischemia. Additionally, CK fluxes of AK1-KO were unaffected. Our data show that dynamic instead of static energetic parameters determine recovery of contractile performance of wild type and AK1-knockout hearts upon ischemia-reperfusion.

Magnesium Deficiency: A Global Gene Expression Study
Northern Kentucky University       Advisor: Patrick Schultheis       Student: Tamara Hagen

Magnesium Deficiency: A Global Gene Expression Study Tamara Hagen, Rachel Di Trapani, Patrick Schultheis Department of Biological Sciences, Northern Kentucky University, Highland Heights, KY 41099 Magnesium is the second most abundant intracellular cation in the human body. It serves as a cofactor in over 300 enzymatic reactions and has a profound influence on many cellular processes including DNA and protein synthesis, intracellular signal transduction, and cell growth and differentiation. Not suprisingly, evidence is accumulating that magnesium deficiency contributes to the pathogenesis of a number of major human disease states such as atherosclerosis, hypertension, diabetes, and asthma. However, the mechanisms underlying magnesium’s role in various pathological processes remain largely undefined. To begin to elucidate these mechanisms, cDNA microarray technology was used to compare gene expression profiles of various control organs (brain, heart, small intestines, liver, and kidney) to their counterparts from magnesium deficient mice. Magnesium deficiency resulted in the differential expression of a wide variety of genes in all tissues examined. One striking aspect of the data was the differential expression of a large number of genes involved in lipid metabolism, including lipases, esterases, fatty acid transporters, and apolipoproteins. This is especially interesting in light of the fact that magnesium is known to modulate blood lipid levels and has been implicated in cardiovascular disease, in particular, atherosclerosis. Data such as these should lead to a better understanding and appreciation of magnesium’s role in health and disease.

LINKING STRATEGIES FOR SOLID-PHASE SYNTHESIS: POLYMER SUPPORTED SYNTHESIS OF CONJUGATED OLIGOMERS
Purdue University Calumet       Advisor: Michael W. Pelter       Student: Dusanka Colovic

LINKING STRATEGIES FOR SOLID-PHASE SYNTHESIS: POLYMER SUPPORTED SYNTHESIS OF CONJUGATED OLIGOMERS DUSANKA COLOVIC, REGINA STRUG, MICHAEL W. PELTER, *AND LIBBIE S. W. PELTER, Department of Chemistry and Physics Purdue University Calumet Paramount to the success of any solid-phase synthetic strategy is a reliable method for coupling the initial starting material onto the solid support. For this investigation, the solid phase linker must be compatible with the reagents and reactions used to prepare oligomers and must allow for efficient cleavage of the product at the end of the synthesis. Since the objective of our research is the synthesis of conjugated oligomers useful in molecular electronic applications, the oligomer must terminate with a functional group that extends conjugation or contributes to the electronic application of the oligomer. Successful strategies that meet these objectives will be given in this presentation. The immobilization of functionalized alkynes has been accomplished through the attachment of 1-(3-hydroxy-3-methylbutynyl)-4-iodobenzene to dihydropyran functionalized 1% crosslinked polystyrene resin. Subsequent carbon-carbon bond forming reactions form supported conjugated trimers or pentamers which, when released from the polymer support, provide compounds with a protected terminal alkyne. A linking strategy for the immobilization of thiophenols has also been accomplished. After elaboration, the supported conjugated oligomers were cleaved from the polymer support as thioacetates. Deprotection affords thiol terminated conjugated oligomers. These compounds then are ideally suited for attachment to a gold surface for the study of their molecular electronic properties.

LINKING STRATEGIES FOR SOLID-PHASE SYNTHESIS: POLYMER SUPPORTED SYNTHESIS OF CONJUGATED OLIGOMERS
Purdue University Calumet       Advisor: Michael W. Pelter       Student: Regina J. Strug

LINKING STRATEGIES FOR SOLID-PHASE SYNTHESIS: POLYMER SUPPORTED SYNTHESIS OF CONJUGATED OLIGOMERS DUSANKA COLOVIC, REGINA STRUG, MICHAEL W. PELTER, *AND LIBBIE S. W. PELTER, Department of Chemistry and Physics Purdue University Calumet Paramount to the success of any solid-phase synthetic strategy is a reliable method for coupling the initial starting material onto the solid support. For this investigation, the solid phase linker must be compatible with the reagents and reactions used to prepare oligomers and must allow for efficient cleavage of the product at the end of the synthesis. Since the objective of our research is the synthesis of conjugated oligomers useful in molecular electronic applications, the oligomer must terminate with a functional group that extends conjugation or contributes to the electronic application of the oligomer. Successful strategies that meet these objectives will be given in this presentation. The immobilization of functionalized alkynes has been accomplished through the attachment of 1-(3-hydroxy-3-methylbutynyl)-4-iodobenzene to dihydropyran functionalized 1% crosslinked polystyrene resin. Subsequent carbon-carbon bond forming reactions form supported conjugated trimers or pentamers which, when released from the polymer support, provide compounds with a protected terminal alkyne. A linking strategy for the immobilization of thiophenols has also been accomplished. After elaboration, the supported conjugated oligomers were cleaved from the polymer support as thioacetates. Deprotection affords thiol terminated conjugated oligomers. These compounds then are ideally suited for attachment to a gold surface for the study of their molecular electronic properties.

Coordination Chemistry of Metallodrugs: Search for New Antitumor Agents
Randolph-Macon College       Advisor: Serge Schreiner       Student: Sarah Crider

Cisplatin along with carboplatin have been useful in treating ovarian and testicular cancer. Compounds similar in structure to cisplatin and carboplatin were prepared using Pt(PhCN)2Cl2 and Pd(PhCN)2Cl2 as starting materials. Various phosphorus-containing ligands were used to substitute the benzonitrile ligands in order to generate square planar mono-chelated and bis-chelated platinum and palladium compounds. After the complexes were synthesized and characterized by multinuclear NMR techniques, antimicrobial tests were carried out. Six types of bacteria were used for inhibition studies: Escheria Coli, Salmonella Enteritidis, Seratia Marcescens, Proteus Volgaris, Pseudomonas Aeruginosa, and Staphylococcus Epidermis. Complexes that showed a greater inhibition of bacterial growth relative to cisplatin and carboplatin included the mono-chelated compounds Pt(dppey)Cl2, Pt(dcpm)Cl2, and the bis-chelated compounds [Pt(dcpe)2]Cl2, [Pt(dcpm)2]Cl2, [Pt(dppey)2]Cl2, [Pt(dppm)2]Cl2, [Pt(dppp)2]Cl2, [Pt(dppbu)2]Cl2 (dppey = bis(diphenylphosphino)ethylene, dcpe = bis(dicyclohexylphosphino)ethane, dcpm = bis(dicyclohexylphosphino)methane, dppm = bis(diphenylphosphino)methane, dppp = bis(diphenylphosphino)propane, dppbu = bis(diphenylphosphino)butane. Solutions of the ligands used to synthesize the compounds were also used in the bacterial tests. In some cases, the free diphosphine ligands showed bacterial inhibition.

Drawing to remember: Improving young children's reports of an experienced event
Randolph-Macon Woman's College       Advisor: Beth Schwartz-Kenney       Student: Kimberly Cuevas

In legal cases in which a child’s testimony is of necessity, one must determine the most appropriate way to obtain the most accurate and complete report of the witnessed event. Children’s accuracy is influenced by a number of factors, such as the child’s age and the type of questioning used. In an effort to increase the amount of information provided without any detrimental effects on accuracy, researchers have examined various interviewing techniques. We were particularly interested in examining the effects of drawing on the memory reports of forty-two 3- to 4-year-old children who witnessed a unique story-telling session. After a 3-month delay, participants were randomly assigned to a draw condition, in which they were asked to draw and tell about the event, or a tell-only condition. Children’s responses to free and direct recall questions were analyzed. Results indicate that when responding to yes/ no, open-ended, and leading questions, children in the draw-only condition reported significantly less incorrect information than those in the tell-only condition. Children in the draw condition also provided significantly more correct responses in the open-ended questions. Interestingly, we found that during free recall children in the drawing condition provided significantly more incorrect information than children in the tell condition. Results imply that when using certain types of questions, the use of drawing can significantly improve the accuracy of children’s reports. Further investigation is underway to examine the influence of drawing after a one-year delay. Results with regards to using age-appropriate interviewing techniques will be discussed.

“It’s Wrong to Tell Lies when you Know it’s a Lie”: Moral Discourse and Aggression in African-American Children’s Oral Narratives about Interpersonal Conflict
Rhodes College       Advisor: Marsha Walton       Student: Alice Davidson

This study investigates the way in which African-American children living in a high-risk, impoverished neighborhood, make sense of interpersonal conflict in their personal stories. A narrative approach to studying aggression allows us to respect individual voices and perspectives among such children, that are often sacrificed in research using standardized testing with pre-determined response categories. In sharing stories about interpersonal conflict, children practice recognizing and affirming (and sometimes resisting) cultural expectations. They create culturally acceptable explanations for undesirable events and evaluate outcomes according to their own developing moral understanding (Bruner, 1990). Participants in this study were 20 African-American children (ages 8-13), who are among a larger group of children living in a dangerous inner-city neighborhood, with whom I have led a weekly nonviolence program since April 2000. Most of these children have lost a friend or relative to violent crime. Participants shared personal stories about interpersonal conflict, and their stories were recorded and transcribed. I am analyzing these narratives using a coding scheme that assesses the type of aggression, and the kinds of explanations and moral evaluations the children give in recounting their conflicts (Walton & Brewer, 2001). This study takes children’s perspectives seriously, as it respects young people as active and integral participants of American society. In a volatile, unstable world, this is a necessary investigation of the way African-American children, living in dangerous, impoverished neighborhoods, come to take up and participate in the moral discourse of their culture as they make sense of their experiences with interpersonal conflict.

Effect of Impurities on the Far-Infrared Dispersion Spectra in Silicon
Saint Michael's College       Advisor: William Karstens       Student: David Bobela

Impurities in semiconductors are commonly studied by measuring absorption bands in the infrared and visible. The associated dispersion in refractive index is normally small and difficult to measure relative to the host-crystal background, especially near strong absorption. However, in regions of high transparency, where the intrinsic refractive index can be accurately determined by standard optical methods, dispersive effects arising from impurity absorptions at low energies are readily measurable and provide an indication of extrinsic absorption as well as a measure of the impurity concentration. Our analysis is based on a Taylor-series representation for the refractive index of intrinsic elemental semiconductors in a transparent region starting from the Kramers-Kronig relations. Only terms in even powers of the energy appear (Cauchy dispersion) and the coefficients are the inverse odd moments of the interband extinction coefficient. Deviations from the Cauchy dispersion in the infrared are the dispersive signature of extrinsic absorption at lower energies and may be approximated by a series in inverse powers of the energy. The coefficients are the odd moments of the impurity absorption—in particular, the coefficient of the E-2 term is the first moment of the impurity absorption spectrum. Due to the f-sum rule, this coefficient yields the concentration to effective-mass ratio for the impurity. We present an application of these methods using data from heavily doped silicon samples.

Tertiary Neutron Measurement by Carbon Activation
SUNY Geneseo       Advisor: Stephen Padalino       Student: Julia Fuschino

State University of New York at Geneseo V.YU. Glebov, D.D. Meyerhofer, P.B. Radha, W. Seka, S. Skupski, C. Sorce, J.M. Sources, C. Stoeckl, Laboratory for Laser Energetics, University of Rochester T.C. Sangster, Lawrence Livermore National Laboratory Due to increased energy demands in the United States, research into new forms of energy production is becoming more important. Fusion ignition, as seen in the sun, is one possible source of energy. The goal of the National Ignition Facility, NIF, is to use a powerful laser to compress and heat a small fuel pellet, start a fusion reaction in a confined region of J. Fuschino, R. Colburn, S. Padalino, L. Baumgart, L. Willsey space, and obtain “energy gain.” The NIF will be able to assist researchers in deepening their scientific knowledge of high-density plasma physics, play a pivotal roll in the Nuclear Stockpile Stewardship, and provide the opportunity for nuclear weapons scientists to maintain their skills. Since research into plasma fusion at these densities is a relatively new endeavor, many diagnostics need to be constructed to measure reaction products such as neutrons. The yield of tertiary neutrons with energies higher than 20 MeV has been proposed as a method to determine the reaction density of Internal Confinement Fusion (ICF) reactions. Carbon activation is an appropriate measurement technique because of its high reaction threshold, its 20.3 min half-life, and its ability to be detected through positron emission. Because the tertiary neutron yield is more than six orders of magnitude lower than primary neutron yield the carbon activation diagnostic requires very pure carbon samples, free from contaminants that will produce positron emitters. We have developed carbon purification, packaging, and handling procedures that minimize the contamination signal to a level low enough to use carbon activation for tertiary neutron measurements in direct-drive implosion experiments with DT cryogenic targets on OMEGA and NIF.

Tertiary Neutron Measurement by Carbon Activation
SUNY Geneseo       Advisor: Stephen Padalino       Student: Leigh Baumgart

Tertiary Neutron Measurement by Carbon Activation J. Fuschino, R. Colburn, S. Padalino, L. Baumgart, L. Willsey State University of New York at Geneseo V.YU. Glebov, D.D. Meyerhofer, P.B. Radha, W. Seka, S. Skupski, C. Sorce, J.M. Sources, C. Stoeckl, Laboratory for Laser Energetics, University of Rochester T.C. Sangster, Lawrence Livermore National Laboratory Due to increased energy demands in the United States, research into new forms of energy production is becoming more important. Fusion ignition, as seen in the sun, is one possible source of energy. The goal of the National Ignition Facility, NIF, is to use a powerful laser to compress and heat a small fuel pellet, start a fusion reaction in a confined region of space, and obtain “energy gain.” The NIF will be able to assist researchers in deepening their scientific knowledge of high-density plasma physics, play a pivotal roll in the Nuclear Stockpile Stewardship, and provide the opportunity for nuclear weapons scientists to maintain their skills. Since research into plasma fusion at these densities is a relatively new endeavor, many diagnostics need to be constructed to measure reaction products such as neutrons. The yield of tertiary neutrons with energies higher than 20 MeV has been proposed as a method to determine the reaction density of Internal Confinement Fusion (ICF) reactions. Carbon activation is an appropriate measurement technique because of its high reaction threshold, its 20.3 min half-life, and its ability to be detected through positron emission. Because the tertiary neutron yield is more than six orders of magnitude lower than primary neutron yield the carbon activation diagnostic requires very pure carbon samples, free from contaminants that will produce positron emitters. We have developed carbon purification, packaging, and handling procedures that minimize the contamination signal to a level low enough to use carbon activation for tertiary neutron measurements in direct-drive implosion experiments with DT cryogenic targets on OMEGA and NIF.

Tertiary Neutron Measurement by Carbon Activation
SUNY Geneseo       Advisor: Stephen Padalino       Student: Robyn Colburn

Tertiary Neutron Measurement by Carbon Activation J. Fuschino, R. Colburn, S. Padalino, L. Baumgart, L. Willsey State University of New York at Geneseo V.YU. Glebov, D.D. Meyerhofer, P.B. Radha, W. Seka, S. Skupski, C. Sorce, J.M. Sources, C. Stoeckl, Laboratory for Laser Energetics, University of Rochester T.C. Sangster, Lawrence Livermore National Laboratory Due to increased energy demands in the United States, research into new forms of energy production is becoming more important. Fusion ignition, as seen in the sun, is one possible source of energy. The goal of the National Ignition Facility, NIF, is to use a powerful laser to compress and heat a small fuel pellet, start a fusion reaction in a confined region of space, and obtain “energy gain.” The NIF will be able to assist researchers in deepening their scientific knowledge of high-density plasma physics, play a pivotal roll in the Nuclear Stockpile Stewardship, and provide the opportunity for nuclear weapons scientists to maintain their skills. Since research into plasma fusion at these densities is a relatively new endeavor, many diagnostics need to be constructed to measure reaction products such as neutrons. The yield of tertiary neutrons with energies higher than 20 MeV has been proposed as a method to determine the reaction density of Internal Confinement Fusion (ICF) reactions. Carbon activation is an appropriate measurement technique because of its high reaction threshold, its 20.3 min half-life, and its ability to be detected through positron emission. Because the tertiary neutron yield is more than six orders of magnitude lower than primary neutron yield the carbon activation diagnostic requires very pure carbon samples, free from contaminants that will produce positron emitters. We have developed carbon purification, packaging, and handling procedures that minimize the contamination signal to a level low enough to use carbon activation for tertiary neutron measurements in direct-drive implosion experiments with DT cryogenic targets on OMEGA and NIF.

Low doses of gamma rays induce deletions in human mitochondrial DNA
SUNY Geneseo       Advisor: Wendy Pogozelski       Student: Timothy Chapman

LOW DOSES OF GAMMA RAYS INDUCE DELETIONS IN HUMAN MITOCHONDRIAL DNA Timothy J. Chapman1, Christopher C. Griffith1, William F. Blakely2 and Wendy K. Pogozelski1 1Department of Chemistry State University of New York (SUNY) College at Geneseo, Geneseo, NY 2Applied Cellular Radiobiology Armed Forces Radiobiology Research Institute, Bethesda, MD It is well known that ionizing radiation, such as that from X rays and gamma rays, damages DNA. Most studies, however, have focused on the DNA that resides in the cell nucleus. Mitochondria, the cellular organelles responsible for energy production, contain DNA as well (mtDNA), but few studies have examined how radiation might affect this type of DNA. The question is an important one, because mutations in mtDNA can be inherited and can lead to disease. However, because so many copies of mitochondrial DNA exist per cell, the damage is difficult to observe and quantify. We have developed a method that enables us to detect dose-dependent damage to mitochondrial DNA. Our method is based on the polymerase chain reaction (PCR), a technique that copies, or amplifies DNA. We amplified a long (11.2 kilobase) fragment of human mtDNA from MOLT-4 lymphoblasts (white blood cells from a former leukemia patient) treated with Cobalt-60 gamma rays. Separation of the products by agarose gel electrophoresis enabled us to visualize the effect of increasing radiation exposure. As radiation dose increased, the amount of the 11.2 kb fragment decreased and shorter bands appeared, indicating that the radiation was inducing breaks in the DNA chain. The effect was seen at doses as low as 75 cGy, an amount seen in therapeutic doses of radiation or in accidential exposure. Further research efforts will be directed at detecting the minimal amount of radiation to which particular cells can be exposed before appreciable mitochondrial DNA mutations occur.

Time-Resolved Analysis of Radio Frequency Plasma
SUNY Geneseo       Advisor: James Mclean       Student: Colin Palmer

Researchers at the Eastman Kodak vacuum coating laboratory are interested in characterizing plasmas used in industrial processes, such as the manufacture of photographic film. A plasma is a gas of ions and electrons and Radio frequency plasmas are used to modify substrates prior to film deposition. For these 40 kHz plasmas the plasma characteristics, such as ion density and electron densities are time dependent. To see how these values vary with time, a probe was placed in the plasma chamber to measure the voltage and current. The data were subdivided into bins corresponding to the driving voltage phases. The results provide an instantaneous measurement of the plasma at different times within the plasma period. This method will enable time-resolved measurements of plasma properties.

"Parental Support and Its Effect on Adolescent Mental Health"
SUNY-Geneseo       Advisor: Anne Eisenberg       Student: Susan Drexel

It is estimated that over fifty percent of all marriages end in divorce and the number of children raised by single parents increased from 11% to 22% from 1970 to 1990 (Entwisle and Alexander 1995: 399). Research indicates that these shifts in family structure have a negative impact on a child's self-esteem (Wagner 1996), success in school (Astone and McLanahn 1991), and friendship formation (Ross and Broh 2000). The literature highlights how specific aspects of family life such as household income (Dahl 1994), quantity, and quality of parent-child interactions affects teen depression (Garber 1997). This reserach examines the relationship between family structure and adolescent mental health. I argue that divorce and non-traditional two-parent families (where both parents work full-time) leads to an increased likelihood for adolescent depression. I hypothesized that teens are sensitive to the quality and quantity of time with their parents, resulting in teens exhibiting several signs of depression based on these interactions. Using a combination of quantitative data from an anonymous survey as well as qualitative data from in-depth interviews with selected teens, I found that many teens are affected by the amount of time spent with their parents. Additionally, I found that a key factor in these relations is the structure that parental guidance provides. as one way that family structure changes, leads to

Circadian Rhythms of Circulatory Physiology and Locomotor Activity in an Aquatic Oligochaete Worm.
Texas A&M University       Advisor: Mark Zoran       Student: Amanda Ebbighausen

Lumbriculus variegatus, lives in lakes with its head in a substrate burrow and tail extended into the water, facilitating gas exchange. Leaving, tails vulnerable to predatory attack and exhibit rapid escape responses. In daylight, the tail maintains a rigid posture avoiding predation and facilitating gas exchange at respiratory adaptations of the tail. Oxygenated blood circulates by peristaltic waves along the dorsal blood vessel from the tail to anterior segments. Many animals possess internal biological clocks entrained by environmental stimuli coordinating the animals physiological processes. We developed a photodiode-based, biomonitoring device to test whether the locomotor activity and circulatory physiology of Lumbriculus exhibits a biological rhythm that entrains to a light/dark cycle and free-runs in constant conditions. Animals were studied in a 12h/12h light/dark cycle and housed in microaquaria (glass capillary tubes). An infrared LED and photocell were placed on opposite sides of the capillary to monitor activity and pulsation rates. Electrical signals associated with light detection (blood pulses and movement) were collected by automated data acquisition for 10 sample periods each hour over 2-7 days. Lumbriculid activity exhibited a diurnal rhythm with bouts of elevated activity during the dark phase. In constant dim light, activity rhythms continued to free-run. Rhythms in activity were accompanied by elevated pulse rates at night. Our data suggest that lumbriculid nocturnal activity patterns and rhythms are governed by internal biological clocks. Studies of biological clocks and cellular and molecular mechanisms that govern them contribute to understanding how environmental cues influence behavior and physiology of animals on earth. Studies of how nervous systems mediate environment regulation of biological rhythms will be important as society develops more convenient mechanisms of travel and humans venture into constant conditions, such as sustained periods of time under the sea or in outer space.

Web Analytics and Emergent Properties of Web Usage Data
Trinity College       Advisor: Ralph Morelli       Student: Matt Bridges

One area where Internet-based entertainment and commerce is at a disadvantage to more traditional forms is in the analysis of customers’ patterns and habits. This analysis can be used to assess the effectiveness and performance of a business. Traditional approaches to web analytics (the analysis of usage patterns and traffic on the web) obtain raw data from web server log files. The data contained in these log files often is not sufficient to distinguish between different clients due to proxies, firewalls, browser caching, and dynamic IP address allocation. As a result, statistical data extracted from these log files can be misleading or inaccurate. This not only makes it difficult for administrators to estimate a web site’s efficacy, but also complicates the task of detecting and preventing web site abuse. Using multiple techniques including session management and relational data storage, I devised a system for gathering raw usage data that overcomes many of the inaccuracies inherent in log file-based web analytics systems. I created tools to analyze the raw data and provide administrators with the ability to observe the activities of their clients in real time. I also wrote analysis tools that take advantage of learning algorithms and Baysian neural network techniques. These tools look for emergent properties in the raw data. Using these tools, it is possible to build a framework for a site where the content organizes itself based on clients’ browsing habits.

COORDINATION GEOMETRY OF HEAVY P-BLOCK METALS
Truman State University       Advisor: James McCormick       Student: Catherine Schmidt

The inherent difficulty in understanding the molecular basis of heavy p-block metal toxicity (i.e. that of metals of the fifth or sixth period in groups 13 through 15), and in developing specific chelating agents to treat overloads of these metals, is their enigmatic electronic and geometric properties. It has been proposed that the toxicity of the heavy p-block metals may be related to their propensity to replace essential metals in enzyme active sites. This proposal cannot be tested, however, because the requisite detailed understanding of the spectroscopy and chemistry of these metals is currently lacking, even for small molecule model compounds. Reported here are our initial studies to remedy this, using the complexes formed between Pb2+ and the ligand tris-(2-pyridylmethyl)amine (TPA). Several complexes of Pb2+ with TPA and variable counter ions have been synthesized and characterized by nuclear magnetic resonance spectroscopy (NMR) and X-ray crystallography. The dependence of the solid-state structure of [Pb(TPA)]2+ on the counter-ion will be discussed, and the novel photochemical behavior of Pb(TPA)(NO3)2 will be presented.

EVALUATION OF INFECTION BY BEAUVARIA BASSIANA AND OTHER NATURALLY OCCURRING ENTOMOPATHOGENIC FUNGI ON THE TICK DERMACENTOR VARIABILIS
Truman State University-Division of Science       Advisor: Laura Fielden       Student: Tiffany Lucas

Ticks cause millions of dollars in livestock losses each year, and are the vectors for diseases like Lyme disease and Erlichiosis. With ticks quickly developing resistance to many pesticides, researchers are looking for natural predators of ticks. One possible biological agent is entomopathogenic fungi. These fungi have been shown to invade the host through the cuticle. This research investigates naturally occurring field infections of the common dog tick, Dermacentor variabilis, as well as the mortalities and infection rates of ticks inoculated with an entomopathogenic fungi, Beauvaria bassiana, in a natural environment. Two groups of adult D.variabilis ticks were placed in natural microhabitats. Ticks in one group were inoculated with a spore solution of B. bassiana. Observations of these ticks were made on a biweekly basis for mortality, weight loss, and on a monthly basis were sampled for fungal cultures. Few ticks appeared to be outwardly affected by deliberate spore inoculation, but exhibited good fungal growth when cultured. Most ticks appeared to die as a result of predation, dehydration and water stress. Under natural field conditions B. bassiana does not appear to be a promising agent for biological control.

A Chimeric Erythropoietin Receptor fusion protein in the TF-1 Erythroleukemia cell line
UCLA       Advisor: Lisa A. Schimmenti       Student: Elena W.Y. Hsieh

Erythroleukemia is a rare form of hematologic malignancy. Interaction of the Erythropoietin (Epo) with the Erythropoietin Receptor (EpoR) is essential for normal red blood cell development. In the human erythroleukemia cell line, TF-1, a chromosome rearrangement was identified at the EpoR (19p13.3). The translocation resulted in a deletion of the 3'end of the EpoR gene and replaced it with a novel sequence, the EpoR fusion partner. The abnormal EpoR in TF-1 cells produces a highly expressed message with a C-terminal deletion of EpoR. We suggest that this abnormal receptor contributes to the malignant phenotype of this cell line. In order to understand the biological significance of the EpoR-fusion partner chimera, we performed transfection studies with constructs encoding an EpoR fusion partner chimera (EpoRTF-1), and an EpoR truncated at the site of translocation (EpoRT). We assayed proliferation rates of the transfected cells growing in Epo and observed that EpoRTF-1 and EpoRT cells proliferate at similar rates and that the EpoRTF-1 construct does not confer growth factor independence. We also obtained a BAC clone containing the fusion partner and mapped it to chromosome 8 by fluorescent-in-situ hybridization. Using this BAC clone we assembled a contig containing the EpoR fusion partner gene and analyzed the sequence using bioinformatic tools. Our results show a predicted gene in our sequence which matches a mouse protein secreted from lymphocytes. We are currently cloning and characterizing the human homologue. The results of this study may lead to improved diagnostics and possibly treatment for erythroleukemia.

Design, Implementation and Testing of an FPGA Neuro-Processor
Univ. Texas - El Paso       Advisor: Patricia Nava       Student: Gilberto Contreras

The purpose of this research is to design and implement a digital neural network in a Field Programmable Gate Array (FPGA). It is believed that the hardware prototyping of such neural network will help study the architectural needs of future intelligent devices. Neural networks offer a flexible and efficient solution to pattern classification problems, such as letter recognition, speech recognition and even stock market analysis. Unlike conventional methods that rely on precise solid data, neural networks have the ability to “learn” and apply previous knowledge to solve a never before seen problem. Recent advancement in FPGA technology and VLSI miniaturization have made configurable logic a very attractive alternative for fast prototyping. A three layer neural network consisting of 8 non-computational neurons, 7 hidden neurons and 4 output neurons has been described in Hardware Description Language (HDL) and synthesized for a Xilinx Spartan II FPGA device. Studies are being developed on the integration of this FPGA neural network with other high-end components like commercial digital signal processors. Such integration will potentially lead to an on-system learning devices and will have a tremendous impact in our everyday lives. To more accurately predict the performance and behavior of our digital neural network, software computer models have been created. These software models, as well as various hardware simulations, are used to verify the validity of the HDL neuron description. Simulations have shown that it is possible to implement such a neural network in a Spartan II FPGA while only consuming 70% of available resources.

Toward Daisy-Chain Polymers
University of California, Los Angeles       Advisor: James Fraser Stoddart       Student: Gilmer Youn

Intermolecular interactions abound in the natural world, providing the basis for the formation of beautiful and complex superstructures. One of the objectives of supramolecular chemists is to imitate nature, by utilizing noncovalent bonds, to construct synthetic, ordered aggregates. Rotaxanes and catenanes illustrate the potential that chemists have to form high-order supramolecular conglomerates and interlocked molecular devices. Here we describe the synthesis and characterization of a monomer¡Xcomposed of a ring-shaped unit, an axle-shaped unit, and a bulky end group¡Xand its self-assembly into a rotaxane-like polymeric array¡Xa so-called daisy-chain polymer¡Xby a novel ring-through-ring threading mechanism. The aggregates, which are stabilized by noncovalent interactions between recognition sites on the ring and axle-shaped components, are incapable of cyclizing by "biting their own tails" because the bulky end group on one end of the daisy-chain polymer is not capable of threading through the cavity of the ring-shaped unit at the other. As such, linear daisy-chain polymers will form, in contrast to the cyclic dimers that have predominated in previous attempts at synthesizing these entities. Daisy-chain polymers are expected to exhibit unusual physical properties in comparison to their all-covalently bonded counterparts.

The Relationship Between Anger Expression, Autonomic Functioning and Cardiovascular Disease
University of Central Oklahoma       Advisor: Mike Knight       Student: John Seagraves

Coronary heart disease (CHD) is the leading cause of morbidity and mortality in the United States. As opposed to previous research employing the medical model, current research has primarily focused on a biopsychosocial interaction as a dominant causal factor in CHD. This study sought to identify possible relationships between anger expression substrates and cardiovascular reactivity (autonomic nervous system activity) to stress. Undergraduate students volunteered from the University of Central Oklahoma’s General Psychology pool. Based on their anger expression scores, derived via the Spielberger State/Trait Anger Inventory and the Buss Perry Aggression Inventory, participants were assigned to high and low groups. Subsequently, participants where exposed to two laboratory stressors, mental arithmetic and cold pressor. During the protocol, measures of blood pressure and heart rate were obtained as well as the continuous acquisition of electrocardiogram R waves. These R waves served as an index of heart rate variability, an indicator of autonomic activity. Binary logistic regression analysis revealed differences between high and low groups in respect to cardiovascular reactivity (heart rate, blood pressure and heart rate variability) during the tasks. Thus indicating that these products of anger are indigenous to a psychosomatic component in the development of coronary heart disease.

" Organ Procurement And Allocation In International Perspective"
University of New Hampshire       Advisor: Jeffrey Salloway       Student: Molly Melvin

Twelve Americans die per day waiting for a transplanted organ, while a new name is added every thirteen minutes to the growing list of 69,000 patients still waiting for an organ. In response to these statistics, the Institute of Medicine researched the allocation of livers in the U.S. in 1996. Research found a significant difference in the waiting period for an organ based on the region of the patient. Flaws in the U.S. system have led the investigator to researching internationally for a more effcient system to implement in the American system. The most innovative and realistic system for implementation is Spain. For the research reported here, the investigator spent ten weeks at La Organización Nacional de Trasplantes (ONT) in Madrid studying the structure, process, outcome, and policies of the Spanish organ procurement and transplant model. Using Spain as a comparative model, the investigator reports the implications of current proposed U.S. legislation for a sickest patient first system and how it will affect distribution.

CHLOROPLAST PROTEIN SYNTHESIS ELONGATION FACTOR (EF-Tu) AND HEAT TOLERANCE IN MAIZE EF-Tu MUTANT
University of South Dakota       Advisor: Zoran Ristic       Student: Kristy Wilson

In a previous study five unique polypeptides of 45/46 kDa were found when a heat tolerant maize line, ZPBL 1304, was exposed to elevated temperatures (35 – 45C) (Ristic et al. 1999). Three of these polypeptides have been identified as EF-Tu, a chloroplast protein synthesis elongation factor (Bhadula et al. 2001). Maize EF-Tu has an over eighty percent similarity in sequence to the prokaryotic EF-Tu (Bhadula et al. 2001). Prokaryotic EF-Tu has been shown to act as a molecular chaperone and play a role in protecting proteins from thermal denaturation (Caldas et al. 1998). It has been hypothesized that maize EF-Tu may play a role in the development of heat tolerance (Bhadula et al. 2001). To shed additional light on the function of maize EF-Tu in relation to heat tolerance, a maize EF-Tu mutant (Zmeftu::mum540) was studied. This maize mutant had decreased level of EF-Tu under high temperature conditions and displayed a reduced tolerance to heat and drought stress. Also, chloroplast proteins from the Zmeftu::mum540 (with lower levels of EF-Tu) showed less heat stability then chloroplast proteins from the parent wild type (wild type has higher level of EF-Tu). We propose that EF-Tu provides protection to heat stress by acting as a molecular chaperone. The significance of my study and its line of research are the possibilities of developing heat tolerance in maize and other plants. This would then effect food production by altering the yield under high temperature conditions.

The use of Taxation to Promote Business Investment
University of South Dakota       Advisor: Raymond Ring       Student: Kelsi Marsh

Inter-jurisdictional tax competition is a rising issue in legislatures today. To attempt to create jobs and strengthen state and local economies, governments are using their tax polices as a weapon to stimulate investment. This study attempts to measure the impact of tax incentives upon hypothetical firms. The research uses underlying economic theory to develop a spreadsheet that can conceptually and quantitatively measure the return of investing a given industry type in several locations. This investigation of tax methods is guided by the work of James Papke(1995). A representative firm with a given asset composition is programmed into a spreadsheet along with a specified tax structure. After the company’s asset composition is entered, the spreadsheet calculates the after-tax rate of return over a 60-year lifetime. The after-tax rate of return provides the measure of tax burdens imposed upon a firm. The representative firm method has three main advantages for examining inter-jurisdictional tax competition: 1.Internal rate of return considers the time value of money 2.Allows one to isolate the impact of various tax structures on a certain industry or firm size 3.Provides a measurement of the federal tax offset. The sites chosen for tax burden analysis are Bismark, ND; Sioux Falls, Yankton, and Pierre, SD; Omaha, NE; Sioux City, IA; St. Joseph, MO; and Eden Prairie, MN. These locations offer a variety of tax policies to investigate. The outcome can inform policy makers on how the selected sites’ tax structures might affect economic expansion.

"Animal Farm" as a model for the dysfunctions of Organizational Communication
University of South Dakota       Advisor: Jill Tyler       Student: Eric Holmes

This critical study shows how George Orwell's "Animal Farm" can be used in an educational setting to to show the pitfalls and perils that can be experienced in Organizational Communication in an entertaining way. All groups, ranging from mandatory to volunteer, experience similar problems within the contexts of Propaganda, Spiral of Silence theory, Hidden Agendas, Manipulation, Nepotism and so on.

Computer-based Technology helps Students Master Concepts and Terms in Introductory Psychology
University of Southern Maine       Advisor: John Broida       Student: Stacie Arsenault

Some say computers can efficiently manage course material and promote learning in large enrollment classes. They are, however, regarded as potentially less useful to older, female, and financially disadvantaged students. We assessed the efficacy of teaching using computers in addition to standard classroom lectures in 10 sections of introductory psychology. Students in "traditional classes" ( receiving three exams over the course of a semester) were compared with students in a "computer enhanced course" where assessments were made weekly in addition to three exams. They had the opportunity to take each quiz up to five times. This encouraged repetition which enhanced long term retention of the course material. The students received feedback in that the computer graded the quizzes as soon as they were completed. They received credit for their highest score which provided incentive for additional effort. This structure increased the amount of time spent studying and forced spaced practice of the material, another key to learning. Few students had difficulty accessing machines. No sex or age differences were found in regard to comfort with computer use. There was also no effect due to differences in learning style. Students in the computer-enhanced courses enjoyed their learning experience and retained more information than students in the traditionally taught sections. Students in the computer enhanced course also demonstrated improved performance on the exams. This suggests that there is a place for technology in the teaching of psychology. It is expected that the results will be generalizable to other large lecture based courses.

Identification of possible digestive enzymes in the whitefly, Bemisia tabaci (B type)
University of St. Thomas       Advisor: Rosie Rosell       Student: Jennifer Sutherland

Bemisia tabaci whiteflies pose a serious threat to agriculture and are vectors of plant viruses in genus, Begomovirus. They damage millions of dollars worth of crops in Texas, Arizona, Florida and many other countries. The virus is ingested as whiteflies feed on the plant phloem. The virus transits the digestive system and enters the next plant via the saliva during feeding. Our research is directed at understanding the insects’ basic digestive system functions, hopefully yielding possible points of interference in the insect-virus-plant transmission pathway. Using a spectrophotometric assay and synthetic cysteine protease substrates, we identified proteolytic activity in whole body extracts and demonstrated optimal activity at pH 5.5. In addition, trypsin and chymotrypsin inhibitors were in-effective toward proteolytic activity. Thus, we suspect it is cystine protease-like. We have been unable to establish first-order enzyme kinetics possibly due to the presence of inhibitors in whitefly hemolymph (blood). Recently, we demonstrated the protein(s) involved in protease activity in whole-body extracts using native and denaturing, reducing gelatin/polyacrylamide gel electrophoresis assays. Current studies are focusing on the 2-dimensional analysis of the protease as well as inhibiting the proteolytic activity using hemolymph proteins and known cysteine protease inhibitors. Once fully characterized, we plan to determine if the enzymes have digestive or homeostatic function by identifying the location of the enzyme in different insect tissues. If the enzymes are digestive enzymes, future experiments will focus on determining how a virus that has a protein coat can survive in the digestive system in the presence of proteases.

Analysis of clonal diversity of unisexual (all-female) killifish hybrids using MHC class I DNA sequences
Ursinus College       Advisor: Kathryn Goddard-Doms       Student: Alicia Morgans

Nearly all fishes reproduce sexually. This study examines one of the rare exceptions: all-female hybrids of two North American killifish species that reproduce clonally. The female hybrids produce eggs with a full complement of chromosomes and the eggs develop without incorporation of sperm, into genetically-identical offspring. A clone is thereby comprised of a female hybrid and all of her identical descendants, potentially spanning many generations and comprising many individuals. Currently, we know of these hybrids from two sites in Nova Scotia, where they coexist with their sexually-reproducing progenitor species, Fundulus diaphanus and F. heteroclitus. Because the sexual progenitors are common at both sites, we initially suspected that repeated hybridizations would have given rise to numerous, genetically-distinct clones. The study of such clonal diversity in these highly atypical vertebrates has provided valuable insights in such ecological questions as how species diversity is maintained and resources are partitioned. To our surprise, our initial studies of allozyme (protein) variation and histocompatibility (immune response) variation by scale-grafting suggested that only one clone was present. To answer this question definitively, we have now generated DNA sequences from major histocompatibility complex (MHC) class I loci and have compared these sequences among individual hybrids to determine whether they are identical (a single clone) or different (multiple clones). At present, we have found considerable diversity in sequences and are currently attempting to distinguish how much of this diversity represents within-individual variation due to multiple MHC I genes, and how much represents genuine, among-hybrid variation indicating high clonal diversity.

Analysis of clonal diversity of unisexual (all-female) killifish hybrids using MHC class I DNA sequences
Ursinus College       Advisor: Kathryn Goddard       Student: Lindsey Lewis

Nearly all fishes reproduce sexually. This study examines one of the rare exceptions: all-female hybrids of two North American killifish species that reproduce clonally. The female hybrids produce eggs with a full complement of chromosomes and the eggs develop without incorporation of sperm, into genetically-identical offspring. A clone is thereby comprised of a female hybrid and all of her identical descendants, potentially spanning many generations and comprising many individuals. Currently, we know of these hybrids from two sites in Nova Scotia, where they coexist with their sexually-reproducing progenitor species, Fundulus diaphanus and F. heteroclitus. Because the sexual progenitors are common at both sites, we initially suspected that repeated hybridizations would have given rise to numerous, genetically-distinct clones. The study of such clonal diversity in these highly atypical vertebrates has provided valuable insights in such ecological questions as how species diversity is maintained and resources are partitioned. To our surprise, our initial studies of allozyme (protein) variation and histocompatibility (immune response) variation by scale-grafting suggested that only one clone was present. To answer this question definitively, we have now generated DNA sequences from major histocompatibility complex (MHC) class I loci and have compared these sequences among individual hybrids to determine whether they are identical (a single clone) or different (multiple clones). At present, we have found considerable diversity in sequences and are currently attempting to distinguish how much of this diversity represents within-individual variation due to multiple MHC I genes, and how much represents genuine, among-hybrid variation indicating high clonal diversity.

Analysis of clonal diversity of unisexual (all-female) killifish hybrids using MHC class I DNA sequences
Ursinus College       Advisor: Kathryn Goddard-Doms       Student: Michelle Janelsins

Nearly all fishes reproduce sexually. This study examines one of the rare exceptions: all-female hybrids of two North American killifish species that reproduce clonally. The female hybrids produce eggs with a full complement of chromosomes and the eggs develop without incorporation of sperm, into genetically-identical offspring. A clone is thereby comprised of a female hybrid and all of her identical descendants, potentially spanning many generations and comprising many individuals. Currently, we know of these hybrids from two sites in Nova Scotia, where they coexist with their sexually-reproducing progenitor species, Fundulus diaphanus and F. heteroclitus. Because the sexual progenitors are common at both sites, we initially suspected that repeated hybridizations would have given rise to numerous, genetically-distinct clones. The study of such clonal diversity in these highly atypical vertebrates has provided valuable insights in such ecological questions as how species diversity is maintained and resources are partitioned. To our surprise, our initial studies of allozyme (protein) variation and histocompatibility (immune response) variation by scale-grafting suggested that only one clone was present. To answer this question definitively, we have now generated DNA sequences from major histocompatibility complex (MHC) class I loci and have compared these sequences among individual hybrids to determine whether they are identical (a single clone) or different (multiple clones). At present, we have found considerable diversity in sequences and are currently attempting to distinguish how much of this diversity represents within-individual variation due to multiple MHC I genes, and how much represents genuine, among-hybrid variation indicating high clonal diversity.

Giant Fluctuations in Water Flow Through a Fractured Rock Medium
Utah State University       Advisor: David Peak       Student: Richard Datwyler

Giant Fluctuations in Water Flow Through a Fractured Rock Medium Richard F Datwyler, Nels J. Rasmussen, Paul D. Simonson (Dr. David Peak), Department of Physics, Utah State University, Logan Utah 84322. Radioactive waste generated during America's experimental breeder reactor program has been in storage at the Radioactive Waste Management Complex (RWMC) in Idaho since the 1960's and 1970's. Measurements performed over the past few years of ground water samples drawn from boreholes at RWMC have large fluctuations in the concentrations of radioisotopes. These readings are unpredictable and occasionally exceed industry standards. In addition to these recent findings, there have been many other observations of great water fluctuations through fractured rock layers. One such study includes the research done by INEEL at the Hell's Half Acre site in Idaho. We have developed a working model that describes the aperiodic, large flow fluctuations observed at the Hell's Half Acre site. We will show the extent to which this model can predict and somehow control the potentially dangerous levels of contamination at RWMC. (Supported by the Office of Environmental Management, U.S. Department of Energy, under DOE-ID Operations Office Contract DE-AC07-99ID13727.)

Giant Fluctuations in Water Flow Through a Fractured Rock Medium
Utah State University       Advisor: David Peak       Student: Paul Simonson

Radioactive waste generated during America's experimental breeder reactor program has been in storage at the Radioactive Waste Management Complex (RWMC) in Idaho since the 1960's and 1970's. Measurements performed over the past few years of ground water samples drawn from boreholes at RWMC have large fluctuations in the concentrations of radioisotopes. These readings are unpredictable and occasionally exceed industry standards. In addition to these recent findings, there have been many other observations of great water fluctuations through fractured rock layers. One such study includes the research done by INEEL at the Hell's Half Acre site in Idaho. We have developed a working model that describes the aperiodic, large flow fluctuations observed at the Hell's Half Acre site. We will show the extent to which this model can predict and somehow control the potentially dangerous levels of contamination at RWMC. (Supported by the Office of Environmental Management, U.S. Department of Energy, under DOE-ID Operations Office Contract DE-AC07-99ID13727.)

Sedimentary Analysis and Microfaunal Survey of Puerto Mosquito, Vieques
Wesleyan University       Advisor: Suzanne O'Connell       Student: Jordan Diamond

Puerto Mosquito, a shallow bay located on the southern shore of Vieques, Puerto Rico, is considered one of the most pristine habitats for dense concentrations of Pyrodinium bahamense var. bahamense, a bioluminescent dinoflagellate. Multiple environmental pressures may threaten this unique biological assemblage: siltation from increased erosion due to upslope building, development and degradation from an expanded tourist industry, and possible contamination from the practices and waste products of the United States military on the bay’s eastern shore. Grab samples collected in a cross-bay transect provide spatial data. The abundance and diversity of ostracods and foraminifera were studied. Ostracod diversity reaches a minimum in the center of the bay with a maximum near the mouth.. Trace element concentrations increase towards the mouth with arsenic levels rising to 12 ppm. Human fecal contamination, indicated by concentrations of Clostridium perfringens, is low. A 1.1 meter core extracted from the northwestern quadrant of the bay, opposite the mouth, determined temporal changes and provid clear evidence of sea level rise. There is a sharp boundary between terrigenous and marine sediment at a depth of 35-40 cm. In the marine sediment, ostracod and foraminifera abundance and diversity remain relatively constant, but trace element concentrations increase in the younger sediment. Additional data focuses on understanding the dynamics of the bay. Grain size analysis and calcium carbonate measurements determine relative productivity and current strength. This environmental analysis provides a baseline survey for future monitoring of this unique and fragile ecosystem.

Rapid Climate Variability in the Oxygen Minimum Zone: Evidence from Diffuse Spectral Reflectance Records
Wesleyan University Earth and Environmental Sciences Department       Advisor: Suzanne O'Connell       Student: Jeffery Del Viscio

Sediment cores were collected in a restricted basin within the Oxygen Minimum Zone (O2 <5 µm/kg; 400-1300 m depth) off the coast of Baja California at 25°N during a 1999 NSF-funded cruise. These records exhibit the most southerly evidence of centennial to decadal scale climate instability yet observed on the open Northeast Pacific margin. My work involved initial shipboard collection of Diffuse Spectral Reflectance (DSR) data sets. DSR is a non-invasive spectral method well suited to high-resolution measurement of fine-scale sediment fabric seen within the Oxygen Minimum Zone, arising from the absence of bioturbating benthic macro-fauna unable to survive under the low oxygen conditions. Subsequent shore-based statistical analysis of DSR data sets produced high-resolution oceanographic proxies capable of identifying decadal to centennial shifts in carbonate and organic carbon from the last deglaciation through the Holocene (15 to 0 Ka). These rapid shifts maybe controlled by changes in local primary production and/or sub-surface water mass ventilation, although the interplay of both processes remains controversial. This study focuses on the surface productivity component because ventilation is minimal in restricted basins. Examination of the spatial/temporal coherence of these DSR derived carbonate and organic carbon fluctuations, through comparison with other high-resolution climatic records, show a positive correlation on both a regional scale (Santa Barbara Basin, Western United States lakes records), and a global scale (GISP2 Ice Core record). Global and regional teleconnection of the DSR signal on such rapid timescales supports the potential for global climatological reorganization within the human lifespan.

The Combinatorial Synthesis of 8-Amino Purines
Western Carolina University       Advisor: William Kwochka       Student: Crystal Olson

In current chemistry literature, there are only a few existing methods of synthesizing purines in a combinatorial fashion. Combinatorial chemistry, which is widely used in the pharmaceutical industry, is defined as ‘the synthesis of compounds containing all possible combinations of monomers (functional groups).’ Before this past summer, purines were made in this fashion by altering the molecular backbone at two different locations. However, a new synthesis for these compounds has been recently established – one that I worked on this past summer while employed at Glaxo-Smith Kline Pharmaceuticals. I was able to alter 8-amino purines at four different sites. This was done in a 2 x 2 x 2 x 2 combination – by adding two monomers to each of the four possible reactive sites. In the end, there was an array of sixteen compounds – out of which, only eight of them were known in the literature. When a compound can be altered in multiple locations, a chemist can perform parallel syntheses and can make a library of thousands of compounds in a relatively short time period, in a cost effective manner. This presentation will focus on the theories of combinatorial chemistry and the synthetic route for making 8-amino purines.

AN ACIDIC PH FUNCTIONS AS AN ENVIRONMENTAL STRESSOR TO SUPPRESS THE NATURAL DEFENSE MECHANISMS OF RANA PIPIENS
WIdener University       Advisor: Itzick Vatnick       Student: Jaime Andrews

The decline in frog populations is a well-recognized worldwide phenomenon. The disappearance of frogs from various locations may serve as a bioindicator of the health of the earth’s habitats. Infectious diseases play a major role in amphibian decline. Our research focuses on host-pathogen interactions and their influence on the natural defenses of frogs. Previous work indicates that a ten-day exposure to mild acid conditions (pH 5.5) results in about 65% mortality of adult Rana pipiens. Furthermore, this work indicates that the normal endogenous gut-bacteria of adult frogs may be the source of the systemic bacterial infection that these frogs experience when they are exposed to an acidic environment. We investigated the inflammatory response of adult Rana pipiens stimulated with thioglycollate, a substance widely used experimentally for this purpose. Inflammation is a natural protective defense against microbial infection, characterized by an influx of leukocytes to the site of infection. When injected into the peritoneal cavity, thioglycollate causes the release of peritoneal exudates containing leukocytes. Our study shows that acid exposure (pH 5.5) greatly suppresses the inflammatory response in thioglycollate-induced Rana pipiens as shown by a substantial decrease in the number of leukocytes found in the peritoneal cavity in acid exposed frogs.

AN ACIDIC PH FUNCTIONS AS AN ENVIRONMENTAL STRESSOR TO SUPPRESS THE NATURAL DEFENSE MECHANISMS OF RANA PIPIENS
Widener University       Advisor: Itzick Vatnick       Student: Emily Piddington

The decline in frog populations is a well-recognized worldwide phenomenon. The disappearance of frogs from various locations may serve as a bioindicator of the health of the earth’s habitats. Infectious diseases play a major role in amphibian decline. Our research focuses on host-pathogen interactions and their influence on the natural defenses of frogs. Previous work indicates that a ten-day exposure to mild acid conditions (pH 5.5) results in about 65% mortality of adult Rana pipiens. Furthermore, this work indicates that the normal endogenous gut-bacteria of adult frogs may be the source of the systemic bacterial infection that these frogs experience when they are exposed to an acidic environment. We investigated the inflammatory response of adult Rana pipiens stimulated with thioglycollate, a substance widely used experimentally for this purpose. Inflammation is a natural protective defense against microbial infection, characterized by an influx of leukocytes to the site of infection. When injected into the peritoneal cavity, thioglycollate causes the release of peritoneal exudates containing leukocytes. Our study shows that acid exposure (pH 5.5) greatly suppresses the inflammatory response in thioglycollate-induced Rana pipiens as shown by a substantial decrease in the number of leukocytes found in the peritoneal cavity in acid exposed frogs.

AN ACIDIC PH FUNCTIONS AS AN ENVIRONMENTAL STRESSOR TO SUPPRESS THE NATURAL DEFENSE MECHANISMS OF RANA PIPIENS
Widener University       Advisor: Itzick Vatnick       Student: Matthew Colombo

The decline in frog populations is a well-recognized worldwide phenomenon. The disappearance of frogs from various locations may serve as a bioindicator of the health of the earth’s habitats. Infectious diseases play a major role in amphibian decline. Our research focuses on host-pathogen interactions and their influence on the natural defenses of frogs. Previous work indicates that a ten-day exposure to mild acid conditions (pH 5.5) results in about 65% mortality of adult Rana pipiens. Furthermore, this work indicates that the normal endogenous gut-bacteria of adult frogs may be the source of the systemic bacterial infection that these frogs experience when they are exposed to an acidic environment. We investigated the inflammatory response of adult Rana pipiens stimulated with thioglycollate, a substance widely used experimentally for this purpose. Inflammation is a natural protective defense against microbial infection, characterized by an influx of leukocytes to the site of infection. When injected into the peritoneal cavity, thioglycollate causes the release of peritoneal exudates containing leukocytes. Our study shows that acid exposure (pH 5.5) greatly suppresses the inflammatory response in thioglycollate-induced Rana pipiens as shown by a substantial decrease in the number of leukocytes found in the peritoneal cavity in acid exposed frogs.

Study of Oxygen Free Radicals in Breast Cells Using Fluorescent Microscopy Kiana Thomas, Tahsa Smith, Maryam Foroozesh, Nitsa Rosenzweig
Xavier University of LA       Advisor: Nitsa Rosenzweig       Student: Keiana Thomas

The work described in this poster presentation focuses on the effect of oxygen free radicals (OFR) on breast cells. OFR play a role in major cellular processes including cell death, carcinogenesis, and apoptosis. The contradicting effects of oxygen free radicals on cellular processes could be attributed to different responses of cells to varying concentrations of oxygen free radicals. The levels of OFR in normal breast cell lines and breast cancer cell-lines was measured. The non-fluorescent Rhodamine derivative, 123 dihydrorhodamine, was used to monitor and quantify the level of intracellular oxygen free radicals in MCF-10A (normal cells) and MCF-7 (cancerous cells). In the presence of oxygen free radicals, 123 Dihydrorhodamine is oxidized to form Rhodamine. When excited at 540nm, Rhodamine fluoresces strongly at 575nm. Our results indicate that the effect of oxygen free radicals on cellular processes is concentration dependent. Our studies also show that the level of OFR in breast cells may correlate with the activity of the intracellular Cytochrom P450. The correlation could be explained by the involvement of cytochoromes in the regulation of the level of intracellular OFR. The effect of the inhibitors 1-Ethynyl pyrene (1-EP), 2-Adamantyl propargyl ether (2-APE), and 2’-methoxyflavone (2’-MF) on the activity of Cytochrome P450 was also studied. Our results indicate that the inhibition of Cytochrom P450 by the inhibitors and the levels of the oxygen free radicals depends on the type of inhibition used.

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