Fall Undergraduate Research Symposium Featuring Student Research In All Fields!
Family Weekend Friday, October 14, 2011 and Saturday, October 15, 2011 Friday, 3:00pm-5:00pm
Saturday, 10:00am-12:00pm Dobbs Unversity Center sponsored by
S CHOL A RLY I NQUIRY
&
R ESEA RCH AT E MORY
Emory College of Arts & Sciences
Fall 2011 Undergraduate Research Symposium October 14th & 15th 2011
All posters will be displayed from 3:00 pm Friday afternoon until 9:00am Monday morning. Each presenter will be available for questions and comments at their posters according to the following schedule: Friday, 3:00pm - 5:00pm Agrawala, Shilpi Bae, Sungeun Birnbaum, Matthew Chan, Charlene Davis, Molly De Gastyne, Joshua Dukkipati, Saihari Shekar Fried, Ian Grozhik, Anya
Hodges, Ashley Li, Ting Li, Will Songjun Lin, Jonathan Lopazan, Anda Mannion, Grant Margolis, Julie Marshall, Stephen Martin, Madhava
McCormick, Lydia Mongue, Andrew Radmard, Sara Ramakrishnan, Sharada Rauscher, Phillip Taussig, Brian Winfield, Manas Woodward, Kerri
Saturday, 10:00am – 12:00pm Agrawala, Shilpi Bae, Sungeun Birnbaum, Matthew Cooper, Kirsten De Gastyne, Joshua Dukkipati, Saihari Shekar Hodges, Ashley Li, Ting
Li, Will Songjun Lin, Jonathan Lopazan, Anda Mannion, Grant Manser, Gwyneth Margolis, Julie Marshall, Stephen Martin, Madhava
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McCormick, Lydia Mongue, Andrew Radmard, Sara Ramakrishnan, Sharada Rauscher, Phillip Taussig, Brian Woodward, Kerri
Fall 2011 Undergraduate Research Symposium October 14th & 15th 2011
HUMANITIES / CREATIVE AND PERFORMING ARTS Cooper, Kirsten The Myth of European Military Superiority Faculty Mentor: Dr. Tonio Andrade, Department of History, Emory University Abstract: Previously, historians maintained that European armies were better trained, better disciplined, and therefore excelled against non-European armies. Due to their training and discipline, European armies could more easily execute advanced field maneuvers without becoming disorganized. This decisive edge was key in the rise of the West as a dominant world power. The problem with this construction is that it was created amidst a dearth of scholarship concerning the non-Western militaries that Europeans faced. Our aim was to look comparatively at military development in Europe and Asia during the sixteenth and seventeenth centuries. Specifically, we focused on the development and use of volley fire, an advance maneuver that is a key pillar in the concept of a uniquely Western way of war. Volley fire is a tactic of firing by ranks to create a constant barrage of gunfire. I focused this summer’s research on the early military manual of the famed Chinese General, Qi Jiguang, looking for evidence of emerging volley fire tactics. I read carefully through a German translation of this manual, Jixiao xinshu (A New Treatise on Disciplined Service, 1560), and then compared my findings with Dr. Tonio Andrade’s translations of the original Chinese version. Through this method we found evidence that Qi Jiguang was using some version of volley fire in the mid-sixteenth century, several decades earlier than the first European usage. This not only undermines the previous Eurocentric theories, but proves the need for even further research into non-European military development.
Lopazan, Anda Tale As Old As Time: The Role of Forgeries in Defining "Art" Faculty Mentor: Dr. Judith Miller, Department of History, Emory University Abstract: Before the outset of World War II, the Dutch painter Han Van Meegeren began forging the greatest Vermeers the art world had ever seen. This series of paintings by Van Meegeren did not at all imitate the style and compositions of Vermeer, rather the forger took elements associated with Vermeer (intense blue and yellow) and gave the art world completely original paintings. Or, in other words, Van Meegeren gave the art world the exact “Vermeers” they were expecting – religious subjects painted in a style that played on hopeful theories about Vermeer’s origins and artistic influences.
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Fall 2011 Undergraduate Research Symposium October 14th & 15th 2011
Van Meegeren’s case has one significantly common trait with other forgeries. Once the deception is uncovered, scholars and writers focus on the forger and the crime he committed - his motivations, his victims, his artistic skill, his earnings. For example, journalist Edward Dolnick in his book sets up the Van Meegeren event as part of the larger picture of World War II, describing how Van Meegeren duped one of the highest Nazi officials. Mark Jones, who curated an exhibition containing forged artwork, writes that the deceptive powers of forgeries result in part because of cultural perceptions that prey upon even the most renowned art experts. Thus, the artistic merit of art produced by forgers is overlooked in favor of its merit ability to deceive, to act as a chameleon. But why should forgeries be seen as more than visual tricks? Because they are fascinating. Forgeries present an enigma and challenges long-standing assumptions about aesthetics, connoisseurship, and art. _________________________________________________________________________________
Mannion, Grant "For we obeyed not his voice:" The Failure of the Confederacy in the Mind of the Southern Clergy Faculty Mentor: Dr. James Roark, Department of History, Emory University Abstract: In the late antebellum- and Civil War-South the church served as the foundation of society, placing members of the clergy in a position of profound impact. Clerical proslavery thought, which posited slavery was sanctioned by God, was at the fore of Southerners’ defense of their peculiar institution. Seeing the war as a necessary means of defending their divinely bestowed institution, the clergy evoked the name of God on behalf of the Southern cause. Relying on providence, the clergy were firmly endowed with the belief the South, as defenders of God’s will, would reign victorious. The current project examines how the clergy’s association between the Southern cause and providence persisted in the midst of and following the defeat of the Confederacy. Through examining sermons, meetings from religious societies’ meetings, and other religious publications, it appears the clergy perceived defeat on the battlefield as chastisement by God. In failing to uphold their covenant with Him, the South ultimately doomed itself to defeat and the dissolution of slavery. Yet Southerners, the clergy preached, had not entirely fallen out of God’s favor. Following the war, clerical thought romanticized the Southern cause, ultimately helping foster the legacy of racial bigotry and white supremacy that would last a century following the War Between the States. _________________________________________________________________________________
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Fall 2011 Undergraduate Research Symposium October 14th & 15th 2011
Martin, Madhava Black Power: African Americans in the Kennedy, Johnson, and Nixon Administrations Faculty Mentor: Dr. Brett Gadsden, Department of African American Studies, Emory University Abstract: This project aims to identify the ways in which African American officials within the federal government sought to advance the goals of the Civil Rights Movement during the presidential administrations of John F. Kennedy, Lyndon Johnson, and Richard Nixon. In order to chart the careers of over thirty African American officials that served in these administrations, this project has looked at a variety of primary sources—such as Senate confirmation hearings, government publications, and autobiographies—along with newspaper articles and secondary literature. Both during and in the immediate aftermath of the Civil Rights Movement, figures such as Clifford Alexander and Arthur Fletcher gained significant appointments to federal posts and challenged discriminatory hiring practices in corporations and federal contractors through the pursuit of affirmative action policies. Aides such as Louis Martin served as intermediaries between presidents and black communities, and cabinet members such as Robert Weaver sought antidiscrimination housing policies in line with Movement goals. In tracing the careers of these and other black government officials, this project ultimately seeks to identify the extent to which the widespread activism of the Civil Rights Movement resulted in increased opportunities for blacks to pursue the objectives of the Movement from positions within the federal government.
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Ramakrishnan, Sharada Gamelan Drum Styles and the Modernization of Gamelan in West Java, Indonesia Faculty Mentor: Dr. TongSoon Lee, Department of Music, Emory University Abstract: Gamelan, traditional to Indonesia, is an ensemble of primarily gong-chime musical instruments (metallophones) which also includes vocals, suling (flute), rebab (two-string bowed fiddle), and the kendang (double-headed barrel drum). In the 1960s and 1970s, gamelan music underwent some transformations, particularly in the drumming style of the kendang. These two decades also marked a tumultuous time in Indonesia’s history. This project explores the stylistic changes in kendang playing to explore musical changes in West Javanese gamelan in the context of 1960s and 1970s Indonesia.
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Fall 2011 Undergraduate Research Symposium October 14th & 15th 2011
With the change in political atmosphere, this region-specific music opened up to stylistic changes including an increase in steadier metric rhythms as well as an incorporation of dance and song. A change in the position of the drum allowed for better leverage for the drummer, which increased the versatility of sounds created, and gave the kendang the popular nickname: “talking drum.” As a result of the political changes, West Java opened up to musical influences including a combination of two West Javanese traditions: ketuk tilu (folk music) and kendang panca (specific to martial arts), which resulted in a style of music called Jaipongan. Jaipongan, characterized by its “powerful” and energetic sound and stronger and higher pitched drum, is currently regarded as the most popular style of music in West Java. These changes in rhythmic style and vigor were primarily reflected in the kendang, since as the sole percussion instrument, it served to lead the ensemble in terms of tempo and rhythm. Currently, these modernized styles are prominent, but pre1960s gamelan music is still highly regarded as the basis for contemporary music. _________________________________________________________________________________ _________________________________________________________________________________
SOCIAL SCIENCES Agrawala, Shilpi White, Black and Brown: Latino Immigration and the Changing Racial Dynamics in Georgia Faculty Mentors: Dr. Irene Browne, Department of Sociology, Emory University and Dr. Mary Odem, Department of History, Emory University Abstract: In the South, race relations have traditionally been defined as between whites and blacks but now a fast growing Hispanic population is challenging these traditional categories and thereby changing intergroup relations. This project looks at Black-Hispanic and WhiteLatino intergroup relations in Georgia by examining two sources of data: 1) voting patterns of black and white legislators on state immigration legislation. And 2) newspaper articles covering this legislation. In order to accomplish this, I created a comprehensive database containing the racial background of the legislators along with their party, gender and vote on three bills. In addition, I completed a sophisticated coding analysis on newspaper articles from the Atlanta Journal Constitution and the Atlanta Daily World, a prestigious black newspaper, cataloging the difference of racial language from each newspaper. From this data, I found that Black legislators voted differently than white legislators. On one hand, leaders of the black community believe in supporting the Hispanic population in order to form an alliance among the minority communities while a part of the black population views the Hispanic population as job competition. Therefore, the traditional racial dichotomy can either evolve to imbibe this growing community or be further divided
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into three separate groups and yielding even more complex intergroup relations. The results from this project will contribute to scholarship on the dynamics of racial categories and intergroup relations in an emerging multiethnic metropolis. In addition, we hope to contribute to a greater understanding of the anticipated and unanticipated consequences of immigration legislation for Latinos, African Americans and Whites in Georgia.
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Bae, Sungeun Commonalities of Expert Professors Faculty Mentor: Dr. Christine Ristaino, Department of French and Italian, Emory University Abstract not available.
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Davis, Molly The Relationship Between Maternal Depression and Infant Positive Affect/Affectivity Faculty Mentor: Dr. Sherryl Goodman, Department of Psychology, Emory University Co-Authors: Matthew H. Rouse, M.A./M.S.W., Emory University and Lisa J. Slominski, Ph.D., Emory University Abstract: Depression is often associated with low levels of positive affect, or mood, and less positive affectivity, a form of temperament. This study aims to determine the relationship between maternal prenatal and postpartum depression and infant positive affect/affectivity. Previous research has indicated infants of depressed mothers exhibit less positive affect than infants of nondepressed mothers. Low positive affectivity, which is correlated with positive affect (Tellegen, 1985), has demonstrated relative stability at a young age (Lemery, Goldsmith, Klinnert, & Mrazek, 1999). It was hypothesized that infants of depressed mothers would show less positive affect/affectivity than infants of nondepressed mothers. Some research found depressed mother-infant dyads spend more time in negative behavior states and less time in positive behavior states (Field, Healy, Goldstein, & Guthertz, 1990). We predicted mothers’ affect would mediate the relationship between maternal depression and infant affect/affectivity. The present study focuses on 163 six-month old infants and 182 mothers (numbers vary based on the task) who participated in videotaped face-to-face interactions. Moment-to-moment coding was used to assign affect scores. Mothers filled out the Infant Behavior Questionnaire-Revised , which measures temperament. Depression inventories were administered to the mothers during the laboratory visits. Results indicate that maternal depression scores for the first six months of the postpartum period were
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Fall 2011 Undergraduate Research Symposium October 14th & 15th 2011
positively correlated with affectivity scores at six months. Maternal low positive affect and maternal prenatal depression scores showed a significant interaction in terms of predicting infants’ six month low positive affectivity. These findings can potentially inform treatment programs for depressed mothers.
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De Gastyne, Joshua Social Network Analysis: Sexual Segregation @ Emory University Faculty Mentor: Dr. James Rilling, Department of Anthropology, Emory University Co-Author: Robin Dunbar, Oxford University ICEA Special thanks to Bernie Hogan, Oxford Internet Institute Abstract: In the new era of online social media, network analysis has transitioned largely from small, real-world communities to large, web-based interactions. This project focuses on three unique types of communities: self-organized "giving circles," non-profit organizations, and college campuses. In each setting, there are different methods of, and motivations for, communication that determine the structure of relationships that are formed in each setting. These relationships were analyzed with data solely from the internet: primarily company websites, Twitter, and Facebook. Key network characteristics such as geodesic distance and overall density are compared between and within communities to characterize each of their unique aspects. Finally, these data are correlated with, or compared to, previous studies to validate findings and establish a future best-practice model for fundraising organizations, activist non-profits, and online social networks.
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Li, Ting How We Believe in What We Believe: Social Influence on Sacred Values Faculty Mentor: Dr. Gregory Berns, Department of Economics, Emory University Abstract: Sacred values are those we won't trade for material benefits. In this research, we have used the functioning MRI brain imaging technique to study the social influence on decision making involving sacred values. Based on previous literature of neuroimaging, we have identified the main pathway for processing sacred value decisions in our brain to be deontological rather than utilitarian. We are interested in how the neural circuit changes, if ever, when we encounter conflicting values from our peers. Inserting the data of how many people agree with the participants in our experiment, we try to imitate the social pressure we may experience in life. Under such pressure, we hypothesize that the mechanism of
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processing sacred values will change and can be detect on a neural level, shifting towards utilitarian pathway. Thus we shall expect a somewhat different brain activation in the functioning MRI brain images, indicating areas related to utility analysis. This will prove the dynamic properties of human brains with the ability of switching between different neural pathways even when dealing with the core of our values. It has further implication as an indicator of our adaptive value systems that we have developed as social animals. When our values are challenged by social opinions, we may take a step back to weigh the utility of our value and the social judgments, thus reduce the risk of being excluded from the society.
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Taussig, Brian The Roles of Prenatal and Postpartum Depression in Infant EEG Faculty Mentor: Dr. Sherryl Goodman, Department of Psychology, Emory University Co-Authors: Cara M. Lusby, M.A. Emory University, Matthew H. Rouse, M.A., M.S.W. Emory University, and Martha Ann Bell, Ph.D. Virginia Tech Abstract: A unique profile of emotion regulation has been observed in depressed adults using electroencephalography (EEG), which measures brain electrical activity. Numerous studies have found this same EEG asymmetry profile in the infants of prenatally and postnatally depressed mothers. Pregnant women experiencing depression are more likely to have elevated levels of cortisol, a steroid hormone related to stress, which may affect the intrauterine environment. Previous studies suggest that infant cortisol is related to infant EEG. The researchers predicted that prenatal depression and prenatal cortisol would together predict infant EEG asymmetry. Prior studies have also found that withdrawal maternal interaction styles are associated with infant EEG asymmetry. The researchers predicted that postpartum depression and greater maternal withdrawal (less maternal intrusiveness) during a dyadic interaction would together predict infant EEG asymmetry. The present study seeks to determine whether these biological and experiential factors strengthen relationships between prenatal and postpartum depression and infant EEG. 73 mother-infant dyads participated in the study. The mothers’ depressive state was measured at multiple points throughout pregnancy and the postpartum period, and infant baseline EEG was collected at a lab visit at 3 months of age, after which asymmetry scores were calculated. Neither the interactive or additive effects of prenatal depression and prenatal cortisol significantly predicted infant EEG asymmetry. Postpartum depression and maternal qualities of interaction did not significantly predict infant EEG asymmetry either. This suggests that prenatal cortisol and maternal qualities of interaction do not play predictive roles in assessing the brain asymmetry in infants of depressed mothers.
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Fall 2011 Undergraduate Research Symposium October 14th & 15th 2011
Winfield, Manas His and Her Brain on Emotion: Neural Responses to Different Types of Negative Memories Faculty Mentor: Dr. Patricia Bauer, Department of Psychology, Emory University Co-Authors: Anne Hermes, Felicia Jackson, Theodore Waters Abstract: We can all observe the relation between memory and emotion. After all, memories that are infused with emotion are the ones that we tend to remember most vividly. Memories that we attach personal personal significance to, or autobiographical memories, are often the most emotionally charged. Previous findings show that negative and positive autobiographical memories are processed differently in the brain. Our project elaborates on this work by investigating, at the neural level, the recollection of neutral vs. negative autobiographical memories. Our experiment splits negative emotions into two subcategories: low arousal negative emotions (including sadness, loneliness, disappointment, failure, and guilt) and high arousal negative emotions (including anger, fear, disgust, anxiety, and hatred). By employing a technique known as event-related potentials (ERP), we measured the brain’s electrical activity in male and female undergraduates while they recollected memories in each category. Our results revealed an “emotion effect” in both males and females in which both subcategories of negative memories were processed differently from neutral memories. The nature of this effect varied between the genders, suggesting that males and females have different patterns of emotional memory processing. This research sheds light on how the brain processes various types of negative memories in males and females, and how the two genders differ in emotional memory processing.
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Woodward, Kerri Parenting Behaviors and Neurocognitive Functioning in the Preschool Period Faculty Mentor: Dr. Patricia Brennan, Department of Psychology, Emory University Co-Author: Katrina Johnson, PhD Emory University Abstract: Research indicates a link between parenting styles and child behavioral and cognitive outcomes. Extremely neglectful or hostile parenting styles can have drastic consequences for functional outcomes in childhood. In contrast, positive and sensitive interactions with both parents may lead to positive neurocognitive outcomes, even for children who are otherwise at risk. This study examines these parenting and child neurocognitive associations in a high-risk sample of mothers and their preschool-aged children (n=84). By
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recording specific behaviors during mother-child interactions and testing the child’s cognitive and linguistic competence, we were able to examine associations between positive, neutral and negative parenting behaviors and child cognitive outcomes. We found that neutral parenting behaviors correlated positively with both cognitive and language function. Positive parenting behaviors were not significantly correlated with child neurocognitive function, however, several specific negative parenting behaviors were negatively correlated with child overall cognitive functioning. Increased understanding of the causal directions of these relationships is needed to better inform interventions for high-risk children. _________________________________________________________________________________ _______________________________________________________________________________
NATURAL SCIENCES Birnbaum, Matthew Fragment Construction for Bottom-Up Synthesis of Functionalized Graphene Nanoribbons Faculty Mentor: Dr. Simon Blakey, Department of Chemistry, Emory University Abstract: Graphene has elicited significant interest from diverse areas of the scientific community. Steps were taken towards constructing 4,4'-dibromo-2,2',5,5'-tetravinyl-1,1'-biphenyl and (1,5-di(prop-1-en-1-yl)naphthalene-2,6-diyl)diboronic acid analogues from the starting materials 2,6-dihydroxynaphthalene and 1,4-dibromo-2,5-dimethylbenzene respectively. These fragments will later act as building blocks for graphene nanoribbons.
_______________________________________________________________ Chan, Charlene Photo-Controlled Hybrid Cell-Cell Junctions Faculty Mentor: Dr. Khalid Salaita, Department of Chemistry, Emory University Abstract not available.
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Fall 2011 Undergraduate Research Symposium October 14th & 15th 2011
Dukkipati, Saihari Shekar Imaging Intracellular Chloride / Network Excitability in Embryonic Motorneurons Faculty Mentor: Dr. Peter Wenner, Department of Physiology, Emory School of Medicine Co-Author: Casie Lindsly, PhD Emory University School of Medicine Abstract: Regulation of intracellular chloride levels is important in the excitability of neural networks. It has been shown that there is an increase in intracellular chloride during the early stages of embryonic development in many vertebrate organisms, and after neuronal injury such as spinal cord injury, tramatic brain injury, and peripheral nerve injury. We are investigating the mechanisms that underlie the regulation of chloride levels by optical imaging with a chloride-sensitive dye called Clomeleon. My project investigated the reliability of this technique as a monitor of intracellular chloride levels in chick embryo motor neurons. We looked at the stability of chloride measurements over extended time periods and also tested the reliability of this technique by adding pharmacological agents that should alter chloride levels. Preliminary data indicate that our measurements provide an accurate assessment of actual chloride concentrations. Therefore, this technique provides a reliable way to look at the mechanisms that regulate chloride in these neurons and thus help to regulate network excitability.
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Fried, Ian Prevalence of Wolbachia in the Tick Amblyomma americanum from Central Georgia Faculty Mentor: Dr. Thomas Gillespie, Department of Environmental Studies, Emory University Co-Authors: Amanda Jo WIlliams, Gene Zhou, Ellen J. Dougan, Gregory A. Dasch Abstract not available.
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Fall 2011 Undergraduate Research Symposium October 14th & 15th 2011
Grozhik, Anya Effects of Hematocrit Manipulation on Offspring Fitness in Chick-Rearing Zebra Finches (Taeniopygia guttata) Faculty Mentor: Dr. Tony Williams, Simon Fraser University Co-Author: Aki Otomo, Simon Fraser University Abstract: During the reproductive period of many species, there exists a trade-off between energy investment in reproduction and parenting or self-maintenance. Costs of parenting have been investigated in a variety of avian species; for example, experimentally exaggerating egg laying decreases egg quality, chick viability, and chick survival to fledging time, and larger clutch sizes present a risk to mothers' survival. It has not been previously studied, however, what costs are brought on by parental provisioning in terms of offspring fitness. We manipulated the foraging capacity of chick-rearing zebra finches (Taeniopygia guttata) via experimental manipulation of hematocrit, and subsequently measured the effects of this treatment on offspring fitness. Although our manipulation of hematocrit was successful, surprisingly we found no effects of low parental hematocrit on chick fitness. We conclude that life for captive zebra finches is not difficult enough to produce measurable changes in offspring fitness; future studies should focus on limiting foraging capacity via hematocrit manipulation along with placement of food source to a location that is more difficult to reach for parenting birds.
Hodges, Ashley Synthesis, Characterization, Biological Stabilities, and Cytotoxicities of Anticancer Gold(III) Sec-butyl-phenanthroline Complexes Faculty Mentor: Dr. Cora Macbeth, Department of Chemistry, Emory University Abstract not available.
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Fall 2011 Undergraduate Research Symposium October 14th & 15th 2011
Lin, Jonathan Spatial Imagery Deficits in the Visually Impaired Depend on Imagery Preference Faculty Mentor: Dr. Krish Sathian, Department of Neurology, Emory School of Medicine Co-Author: Simon Lacey, PhD Emory University Abstract: Spatial cognition has been investigated extensively in the sighted and the blind. However, no study to date has directly compared spatial imagery in these groups in the context of object-spatial imagery preferences. Here we used a spatial imagery task as an index of spatial cognition to examine differences between visually impaired participants (twenty late-onset blind persons) and sighted participants matched for age and gender. The task involved memorization of a 4Ă—4 lettered grid in an initial training period, using visual presentation in the sighted and a combination of auditory and/or haptic presentation in the visually impaired, i.e., reading aloud and/or Braille. Subsequently, auditory cues were used to trigger imagery of the two-dimensional shapes formed by mentally tracing four-letter sequences from the grid. In a two-alternative forced-choice paradigm, participants were asked to decide whether the shapes formed by two consecutive (but not identical) sets of letters were the same or different. Accuracy was significantly lower in the visually impaired object imagers compared to the sighted object imagers, but only a trend was present when comparing visually impaired and sighted spatial imagers. However, imagery preference alone did not modulate accuracy within the visually impaired or sighted groups. These results suggest that the deficits in spatial cognition observed in the visually impaired are more pronounced in object imagers compared to spatial imagers.
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Li, Will Songjun Characterizing Aspects of Visual Working Memory in Humans Faculty Mentor: Dr. Matias Palva, University of Helsinki Abstract: Visual working memory (VWM) is used to maintain sensory information for cognitive operations, and its deficits are associated with several neuropsychological disorders. VWM is based on sustained neuronal activity in a complex cortical network of frontal, parietal, occipital, and temporal areas, and also require a binding of multiple facets of the visual stimuli. However, the neuronal mechanisms underlying this distributed processing through the cortex while sustaining coherent mental images have remained unknown. In a previous study, we mapped the anatomical and dynamic structures of network synchrony supporting VWM by using a neuroinformatics approach and combined magnetoencephalography and electroencephalography (Palva et al., 2010). In that study,
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the stimuli consisted of one to six colored squares in a delayed-match-to-sample task paradigm. In this study, we examined network synchrony and neural mechanisms in three aspects of the VWM system, including color, shape, and spatial location. We also examined the role of a distracter in maintaining neural activity during the VWM task. Behaviorally, the average response accuracy decreased in the distracter trials, and though we attempted to normalize difficulty across the three aspects of color, shape, and spatial location, the shape task was much more difficult for the subjects. Using MEG/EEG (MEEG) data collected during the task, we found that phase synchrony was strengthened in the shape and distracter tasks among the frontoparietal regions known to underlie executive and attentional functions during memory maintenance. However, further analyses are needed to note any differences between these neural networks responsible for the different aspects of VWM.
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Manser, Gwyneth Behavioral Response and Mortality of Grass Shrimp Palaemonetes pugio Exposed to South Louisiana Crude Oil and Hiclean Chemical Dispersant Faculty Mentor: Dr. Sue C. Ebanks, Savannah State University Abstract: Crude oil spills are an increasingly common threat to the marine ecosystem (Daling et al., 1997), and the biological effects of chemical dispersants used in remediation efforts remain unclear. Dispersed oil is potentially more bioavailable (Jung et al., 2009), and sublethal effects on marine invertebrates could have a profound effect on the ecosystem (Perkins et al., 1979). In this study, grass shrimp Palaemonetes pugio were exposed to varying concentrations of Hiclean chemical dispersant and South Louisiana Crude oil to determine behavioral patterns and LC50. The LC50 of dispersed oil to P. pugio was estimated to be between 1.23 and 1.66 ppm. Palaemonetes pugio exhibited increased activity level, relative to controls and lower concentrations, in dispersed oil concentrations at and above 2.083 ppm, after an acclimation period. Thus, grass shrimp may be subject to the influence of positive feedback due to increased activity levels.
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Fall 2011 Undergraduate Research Symposium October 14th & 15th 2011
Margolis, Julie Pathology of an Archaeological Population: Erosive arthropathies found in skeletal remains at 'Atele, Tonga Faculty Mentor: Dr. Hallie Buckley, University of Otago Abstract not available.
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Marshall, Stephen DNA Origami Structure Assembly Rate Enchancement Through Membrane-Bound Nucleation Faculty Mentor: Dr. Khalid Salaita, Department of Chemistry, Emory University Abstract: DNA origami is a new field in which the specificity of the Watson-Crick base pairing interactions of DNA is utilized to create multidimensional structures at the nanoscale. The DNA origami method has gained widespread interest because it provides an approach to organize molecular structures on the nanoscale length scale which is very challenging. However, the scope of DNA origami is limited by its relatively low yield and slow rate of assembly. The central hypothesis of my project is that by anchoring several of the DNA strands that make up a DNA origami structure onto a two dimensional lipid membrane bilayer, the rate of assembly and the yield of the desired structure will increase drastically. This is due to the local concentration effect of constraining the strands in two dimensions, which will bring the strands within close proximity and reduce the entropic costs to assembly. I hope to accomplish this goal by generating a fluid, homogeneous lipid bilayer which will be functionalize with DNA by taking advantage of the affinity of cholesterol modified strands to the hydrophobic lipid membrane. These anchor strands will nucleate the assembly of a hexagon based nanoribbon structure. The assembly process will be monitored using fluorescence microscopy and characterized using AFM. Once the technique has been optimized, it will be applied to a more commonly utilized scaffold structure. The project will ultimately help develop new tools for building structures at the nanoscale and provide new insight into the dynamics of reactions and assembly processes on lipid membranes.
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Fall 2011 Undergraduate Research Symposium October 14th & 15th 2011
McCormick, Lydia The Role of Honey Hydrogen Peroxide H2O2 as a Natural Defense Mechanism Against Small Hive Beetle Aethina tumida Faculty Mentor: Dr. Berry Brosi, Department of Environmental Studies, Emory University Co-Authors: Keith Delaplane, PhD University of Georgia Abstract: Small hive beetle (SHB, Aethina tumida) is a devastating pest of honeybee (Apis mellifera) colonies. While various chemical treatments and traps have been employed to control SHB, it is possible that honeybees produce natural chemical defenses in their honey. The objectives of this project were: 1) To examine the effect of honey hydrogen peroxide on SHB survival, and 2) To determine honey hydrogen peroxide concentrations in colonies with various degress of SHB. Adult SHB were incubated in habitats with experimentallyadjusted honey H202 concentrations (0-4,000 µg/ml). Results showed a 20-50% decrease in survival with the highest concentrations being the most detrimental. Most significantly, survival was best in the catalase group (H202 absent). Field studies were conducted at the UGA Bee Lab (Athens, GA). Honey samples were obtained from 3 hive sites in healthy hives (brood frames, honey frames, uncapped nectar) as well as in sugar-water fed colonies. H202 content was measured with a colormetric microplate assay. Brood honey and nectar had the highest H202 content while sugar-water fed colonies had 75% reduced H2O2 concentrations. Finally, nucs were experimentally treated with and without SHB. Honey samples were obtained longitudinally and H202 measured. While still in progress, the control honey H2O2 decreased 60% while the experimental group was largely unchanged. In conclusion, this data supports that honey H2O2 effects SHB survival and may be regulated within colonies. Given that glucose oxidase controls honey H202, its molecular regulation could be connected to honeybee SHB resistance and overall colony health.
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Mongue, Andrew Genetic Investigation of North American Monarch Butterfly Populations Faculty Mentor: Dr. Jaap de Roode, Department of Biology, Emory University Co-Authors: Amanda Pierce, Graduate Student Emory University, Justine Lyons, PostDoctoral Research Associate Emory University Abstract: Monarch butterflies have interested people for over one hundred years for the spectacular migrations that eastern North American monarchs undertake annually to overwinter in Mexico. Despite this long history of popularity, much remains unclear about this phenomenon. For example, while eastern monarchs travel from the east coast all the way to
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Mexico, western monarchs seem to remain west of the Rocky Mountains and overwinter along the Pacific coast in California. It is conservationally important to establish if or to what extent the two groups come into contact and, more importantly, interbreed (Brower 1995). Scientists have attempted to genetically answer this question before using mitochondrial DNA but this attempt failed due to limited variation in the markers used (Brower 1991). Here we present a more robust genetic analysis of eastern and western populations using DNA microsatellites that shows that they are in fact one large population. _________________________________________________________________________________
Radmard, Sara Synapsin I and Dysbindin I, a Schizophrenia–Related Gene, are Implicative in Synaptic Vesicle Motility Regulation in Drosophila Faculty Mentor: Dr. Mani Ramaswami, Trinity College Dublin Abstract: Habituation is the simplest form of learning that occurs when a decreased response is exhibited after a prolonged, repeated stimulus (Rankin et. al 2009). The Synapsin I proteins, which form a synaptic vesicle reserve pool in the nerve bouton, have been found to play a role in short-term habituation (STH) in Drosophila (Das, 2011; Sadanappa et al., unpublished). In mice Synapsin I levels change proportionally with Dysbindin I, a Schizophrenia-related gene, expression levels (Fei et. al 2010), suggesting Dysbindin I regulates Synapsin I. Although Synapsin I and thus Dysbindin I are implicated in the regulation of STH, a mechanism by which this occurs has not been readily identified (Rankin et. al 2009). We utilized fluorescence recovery after photobleaching (FRAP) at the neuromuscular junction (NMJ) in Synapsin I-/- and Dysbindin RNAi Drosophila larvae to determine if Synapsin I and Dysbindin I regulate synaptic vesicle motility. We found that pending a larger sample size, Synapsin I regulates synaptic vesicular motility and Synapsin I is involved in the formation of a synaptic vesicular reserve pool.
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Fall 2011 Undergraduate Research Symposium October 14th & 15th 2011
Rauscher, Phillip Effects of Adjacent Rubbery Layers on the Physical Aging Rate of Polymer Glasses Faculty Mentor: Dr. Connie Roth, Department of Physics, Emory University Co-Author: Laura A. Gray, B.S. Physics, North Carolina State University Abstract: Polymers are ubiquitous in modern science and applications range from pharmaceutical drug delivery to nanotechnology to gas permeation. Most polymers form glasses below their glass transition temperature (Tg; above which the polymer is liquid-like and below which it is glassy), and subsequently undergo physical aging, a process in which the polymer chains shift into a lower-energy conformation. The physical aging rate, like the glass transition temperature is highly dependent on the film thickness and the stress on the film during glass formation. It has been shown that polymer-polymer interfaces can significantly impact the glass transition temperatures, which has applications in gas permeability, in which a thin glassy layer is often supported by a soft rubbery one. Therefore, it is reasonable to expect that the glassy/rubbery morphology described above could also have distinct physical aging behavior. This study investigates the effect of a silicon-supported underlayer of soft, rubbery Poly n-Butyl Methacrylate (PnBMA) on the physical aging rate of Polystyrene (PS). The first stage of the experiment shows that the aging rate of the glassy PS layer (held at constant thickness) is independent of the thickness of the PnBMA layer, indicating that the rubbery nature does not provide any relief to the glassy layer from the stresses inherent in glass formation. The current trials focus on varying the thickness of the glassy layer.
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