Thee Interferon-Stimulated Gene IFITM3 Decreases Reovirus Infection Efficiency in Hela Cells

s of Student Research Projects The abstracts are listed in alphabetical order by the last name of the lead student author Thee Interferon-Stimulated Gene IFITM3 Decreases Reovirus Infection Efficiency in Hela Cells Amanda A. Anafu Professor Geoffrey Holm, Department of Biology, Colgate University Reoviruses are double-stranded RNA viruses that infect the mammalian respiratory and gastrointestinal tract. In newborn mice, these viruses injure a variety of host tissues, including the brain, heart and liver. Reovirus infection elicits a number of host defense responses, including the production of interferons (IFNs), which trigger cellular antiviral pathways through the induction of interferon stimulated genes (ISGs). Although hundreds of ISGs have been identified, the functions of most of these genes are not known. Among the ISGs is a family of proteins of unknown function, called the interferon inducible transmembrane (IFITM) proteins. One member, IFITM3, has recently been shown to restrict influenza virus entry. As IFITM3 resides in late endosomes, where reoviruses undergo proteolytic disassembly, we sought to determine whether IFITM3 also restricts reovirus entry. Cells constitutively expressing IFITM3 (HeLa-IFITM3) or control cells (HeLa-Scr) were infected with reovirus at various multiplicities of infection (MOI). Efficiency of infection was assessed 18h post-infection by determining the percentage of infected cells via immunofluorescence microscopy. HeLa-IFITM3 cells were less susceptible to infection by reovirus, as they exhibited significantly lower percentages of infected cells in comparison to HeLa-Scr cells. However, this difference diminished at higher MOI. To control for factors associated with protein over-expression, we performed similar experiments in cells expressing an siRNA targeting IFITM3 (HeLa-shIFITM3) and control cells, which were either mock-treated or treated with human interferon-β for 4h prior to infection. Preliminary results suggest that HeLa-shIFITM3 cells exhibited a smaller decrease in infection in the presence of IFN than the control cells. These results suggest that IFITM3 restricts reovirus replication, likely at the cell entry stage. On-going research seeks to use confocal imaging to track labeled viral particles as they enter the endosomal compartments of both HeLa-IFITM3 and control cells. Spatial Learning in Crayfish: Salience of Visual and Tactile Cues Kate Andrews Professor Ann Jane Tierney, Psychology Department, Colgate University Several experiments were performed with crayfish, Orconectes rusticus, to examine the specific types of cues crayfish use when learning a new environment. Past research indicates that crayfish will initially spend time actively exploring a new area. Once they become familiar with the environment, this exploratory behavior decreases. A change to the environment can result in renewed exploration. We used these behaviors to determine if visual or tactile cues are most salient to crayfish as they learn spatial information. Animals were tested in arenas that were divided into an equal grid of squares and had movable panels that allowed for topographical and visual changes. In one experiment, crayfish were allowed to explore the arena for three hours a day, over a series of three days. On the fourth day animals experienced a probe test during which the arena was altered. One group experienced altered visual cues, one group experienced altered topography, and a control group experienced no change. Exploratory behavior was measured by the number of grid squares entered, the time spent moving, the time spent in contact with walls, and the time spent in contact with panels. In the second experiment, the same arena was used and animals were tested in a single day rather than over a series of days. Each animal spent five hours in the arena with exploratory behavior measured for the 1st and 5th hour. Crayfish were then removed from the arena for an hour while the arena was altered to have either novel visual or tactile cues. Animals were placed back in the now altered arena for an hour and exploratory behavior was recorded. In both experiments, crayfish habituated to the arena environment, displaying decreased time and distance walked in a single learning trial and across different days. Preliminary results indicate that, during the first 10-minute segments of the probe tests, crayfish crossed significantly more squares when topographical cues were altered relative to visual cues or the control condition. The crayfish in the topography-change group apparently recognized that the environment had changed and engaged in renewed exploration. These data suggest that, compared to visual cues alone, topographical features are more salient to crayfish as they learn about and remember new environments. The Effects of Altered Core Temperature on Cardiovascular Strain, Thermal Strain and Performance Logan Arena, Eric Hultquist, Wesley Lefferts Professors Dr. Denise Smith, Dr. Patricia Fehling, Health and Exercise Sciences Department, Skidmore College Exercise in environmental extremes elicits physiological alterations in thermoregulatory, cardiovascular, and metabolic function in humans. Purpose: The purpose of this study was to examine cardiovascular, metabolic, and performance responses during maximal exercise performed at 3 different core temperatures: normal, elevated, and depressed core temperature. Methodology: Ten healthy, highly-fit males were recruited to participate. On separate days, the normothemric condition was performed first followed by pre-cooling and pre-heating conditions in a randomized order. Participants were submerged in water up to their armpits at 23.1 and 38.9 °C in the pre-cooling and pre-heating conditions, respectively, followed by a brief transition period prior an incremental, maximal treadmill test. Results: Submersion resulted in significantly altered mean core temperature prior to exercise among the control (0.1 ± 0.2 °C), pre-cooling (-0.5 ± 0.2 °C), and pre-heating (+0.8 ± 0.2 °C) conditions. Core temperature remained significantly different throughout the exercise protocol and furthermore, the pre-cooling condition had a significant condition x time interaction versus the other two conditions. Mean and peak oxygen consumption was not significantly different among trials. Precooling participants resulted in a 8-10 b·min-1 reduction versus pre-heating and control condition at any given time point during the exercise protocol including peak (pre-cooling 178.4 ± 9.3 b·min-1; pre-heating 186.7 ± 7.8 b·min-1; control 188.2 ± 5.8 b·min-1). Time to fatigue was significantly longer in the control condition (914.3 ± 97 sec) versus the pre-heating (879.9 ± 96.3 sec) and pre-cooling (889.2 ± 96.5 sec) conditions. Conclusion: Depressions (pre-cooling) in core temperature significantly reduced cardiovascular strain at any given workload and significantly changed participants’ thermoregulatory response to exercise. Alterations in core temperature did not increase the metabolic strain placed on participants, however, pre-cooling and heating decreased time to fatigue. Early onset of fatigue without increased cardiovascular or metabolic strain can be attributed to central fatigue and depressed sympathetic activity for the pre-heating and pre-cooling conditions, respectively. Phylogenetic Analysis of Nematodes Using Ribonuceloproteins Barsha Baral, Shahin Islam Professor Chang, Biology Department, Hamilton College As the most abundant and diverse roundworm in the phylum pseudocoelomates, with over 100 million undescribed species, nematodes are very difficult to classify morphologically because they are as small as 2.5mm long. Instead, their genomic data can be useful. Studies by De Ley and Blaxter (References) showed that small subunit ribosomal DNA (ssrDNA) was the best locus for molecular classification in nematodes. However, a fully conclusive phylogenetic tree has not been provided yet. Our research foci are to find new phylogenetic markers, design degenerate primers to amplify regions of interest from known and unknown nematode species, and reconstruct phylogenetic relationships among these nematode species based on the newly retrieved sequences. A former Hamilton graduate, Suman Sarkar ’11 sampled sequences from nine species across the animal kingdom: Trichoplax adhaerens, Homo sapiens, Caenorhabditis briggsae, Caenorhabditis elegans, Brugia malayi, Shistosoma mansoni, Giardia lamblia, Leishmania braziliensis, and Trypanosoma cruzi and found that ribosomal proteins L10e, L12e, L15e and L19e were highly conserved. We aligned RPL19e and RPL8 sequences from 14 different nematode species in NCBI and KEGG databases and we designed degenerate primers targeting the most conserved regions. We then sequenced PCR products amplified from cDNA of five nematode species: Cephalobus cubaensis, Acrobeloides uberrinus and Cephalobus sp., Eucephalobus sp., andAcrobeloides buetchlii. Our results showed that the primers designed specifically against RPL19e (~150aa) and RPL8 (~100aa) successfully amplified the region of interest. However, we still need to confirm whether or not the same primer combination would work on virtually all unknown nematode species, for which further testing of the primers is necessary. Because 100aa and 150aa provide little phylogenetic information, we are adding more markers into our study in the future. The Effects of Facebook on Siena College Students Krista R. Bartholomew Professor Dr. Paul Murray, Sociology Department, Skidmore College This project looked at ways in which Facebook affects students. Some questions asked how students use Facebook, how much of a distraction Facebook is, and awareness of Facebook privacy policies. An electronic questionnaire was e-mailed to all current Siena students. There were 457 responses. The main reason Siena students use Facebook is to connect with distant friends. Underclassmen are more likely than upperclassmen to use Facebook for schoolwork-related reasons. There is some negative correlation between time spent on Facebook and GPA, but it is not significant. The majority of students do not believe Facebook is their biggest distraction. Female students are more likely than male students to have their profile set to private, to deny a friend request from a stranger, and to block someone who has made them feel uncomfortable. Most students are at least somewhat aware of Facebook’s privacy policy. Speaking of Smells: The Relationship Between the Verbal Description of Odors and Memory Recognition Nicole K. Beers, Amy E. Callahan Professor Dr. David Hornung, Biology Department, St. Lawrence University Smell is often associated with strong memories yet much remains to be discovered about the relationship between the two. Specifically of interest in the present study is the effect that the verbal description of an odor has on memory recognition. Intuitively, it is suspected that verbal description would improve subsequent memory performance. However, the phenomenon of “verbal overshadowing” suggests verbalizing a perceptual experience may actually interfere with one’s ability to accurately recall a memory. In the study, the subjects’ ability to recognize specific odors after simply smelling them is compared to the recognition ability of subjects who verbally describe the odors. Subjects were randomly placed into one of three groups for Phase 1 where they were asked to either self-generate a description, choose a description, or solely smell each target odor. After initially smelling the odors, all subjects participated in an unrelated task before being presented with a set of 20 odorants, 8 being the target odors from Phase 1. Odorants from the 20-odor set were presented one at a time and subjects were asked to indicate if they recognized each particular odorant from the original set. Since describing the odorants reduced the ability to “remember” the smells as compared to the group that used no names at all, the results are consistent with the hypothesis that verbal overshadowing reduces the accuracy of olfactory memory. Synthesis of Cyclotri (3,3ꞌꞌ-para-terphenyldiyl ethynylene), a Novel ShapePersistent Macrocyclic Carbon Single-Wall Nanotube Precursor. Jonathan C. Bennion, Katelyn E. Bunker, Jenna I Gifford Professor Dr. Thomas Hughes, Department of Chemistry and Biochemistry, Siena College Shape-persistent phenylene ethynylene macrocycles have attracted attention because of their ease of synthesis and supramolecular properties. However, the reactivity of the alkyne moieties could allow conversion of the nominally planar ethynylene macrocycle into compounds with a dimensionality along the axis of the macrocycle; the result is a precursor structure for single-wall carbon nanotube segments. To incorporate the para-terphenylene units into the title compound, the synthesis of an ethynylterphenyl monomer was undertaken, which will be followed by statistical macrocyclization under highly dilute Sonogashira cross-coupling conditions. Heat-Seeking Behavior in Bird Lice: Thermal Cues Mediate Host-Parasite Interactions Rachel Boughton Dr. Christopher Harbison, Biology Department, Siena College Ectoparasites are often forced to choose between obtaining resources and escaping from host defenses. This decision is especially important for the feather-feeding wing lice of pigeons and doves. Wing lice feed on downy feathers only found on bird body regions. However, when in these resource-rich regions, lice are vulnerable to host preening. To escape preening, wing lice migrate away from their food source to hide in the barbs of wing and tail feathers. Here, we show louse thermo-orientation aids in their migration between the body and flight feathers. Lice were capable of orienting on thermal gradients similar to those found on birds. Additionally, we show that food deprivation changes the temperature preference of lice; staved lice show greater preference for temperatures associated food-rich body regions whereas fed lice prefer temperatures associated with safer flight feathers. Studying thermo-orientation behavior can provide a clearer picture of how parasites use host resources and transmit between hosts. Chemical Biology of cell wall-altering agents in Penium margaritaceum, a unicellular model system for anisotropic growth studies in plants Hannah Brechka and Carly Sacks Professor David Domozych, Department of Biology and Skidmore Microscopy Imaging Center, Skidmore College The Charophycean Green Algae (CGA) represent some of the closest relatives to land plants and could provide a key to understanding their ancestry as well. Penium margaritaceum is a unicellular member of the CGA and recent analyses have demonstrated that this desmid produces a cell wall containing many of the polymers found in higher plant cell walls. Homogalacturonan (HG), rhamnogalacturonan-I (RG-I) and cellulose constitute the dominant wall macromolecules, and are organized in three distinct layers as visualized using transmission electron microscopy. Development of these polymers during wall expansion can be analyzed using live cell labeling with monoclonal antibodies raised against epitopes of similar polymers of land plants. The stable cylindrical phenotype of this alga also allows for quantitative assessment of new wall growth. In this study, we interrogated the wall synthesis mechanism and alterations to the cell wall using a variety of agents that disrupt wall development. A Tale of Two Interglacials: A Stalagmite Stable Isotope Record Of Climate in Yucatán, Mexico Since 128,000 YBP Logan Debra Brenner Professor Amy Frappier, Geosciences Department, Skidmore College Earth’s glacial climate has been punctuated with warm interglacial periods lasting ~10,000 years each. Current anthropogenic greenhouse gas forcing is pushing climate towards a state that deviates from the established Quaternary patterns. In predicting future rapid climate two key analogs are the end of the last glacial, Termination 1 ~14,000 years ago, and the Eemian, which is the penultimate interglacial ~130114,000 years ago. Speleothems, or cave formations, record changes in the isotopic composition of rainwater infiltrating the cave during these paleoclimate shifts. Stalagmite YAX-2 was deposited in Yucatán, Mexico within a ~40m deep cave lacking natural entrances from ~128,000 years ago to the most recent millennium, therefore including both analogs. U/Th dating shows that YAX-2 grew most rapidly during interglacials. We present the YAX-2 record of stable carbon and oxygen isotope values as indicators of environmental change in Yucatán, Mexico and compare our results to published research on abrupt tropical climate change and interglacial dynamics. Effects of MNTBAP and Co Treatment on Adiposity and Rev-Erb Dependent Expression Tim Brodsky, Michelle Finan, Lily Ng, and Aaron Sheppard Professor T.H. Reynolds, Department of Health and Exercise Sciences, Skidmore College PGC-1α is a master regulator of mitochondrial biogenesis and is regulated by the transcriptional repressor, Rev-ERB. Rev-ERB may be inhibited by carbon monoxide (CO), a byproduct of the degradation of Heme by the enzyme HO-1. MnTBAP is a heme-like compound that appears to turn-on mitochonadrialbiogenesis and cause weight loss in obese mice. We have investigated the effects of MnTBAP or CO treatment on Rev-ERB dependent gene expression. In obese mice treated withMnTBAP, we observed significant reductions in adiposity andan increase in PGC-1α and ApoCIII expression, two targets of Rev-ERB. CO treatment resulted in no changes in adiposity butApoCIII appears to increase. Therefore, preliminary data indicates that decreases in adiposity appear to be unrelated to changes in RevERB dependent gene expression. Chronic Cannabinoid Exposure During Adolescence Affects C-Fos Expression in Brain Areas That Mediate Sexual Motivation in Adult Female Rats Samuel I. Brook Professors Hassan H. Lopez, Ph.D., Alicia J. Saylor, Ph. D., Neuroscience Program, Skidmore College The endocannabinoid system seems to play an important organizational role in the development and emergence of neuroendocrine systems that regulate female sexual behavior. In particular, chronic cannabinoid exposure during adolescence decreases behavioral measures of sexual motivation in adult female rats, and is associated with a decrease in CB1 receptor expression in the hypothalamus and amygdala. We investigated the effect of chronic cannabinoid exposure at the cellular level by assessing neuronal activity within several brain regions that are thought to mediate sexual motivation in female rats. The synthetic cannabinoid CP-55,940 was chronically administered to adolescent female rats once daily (0.4 mg/kg, i.p.) for 10 days (PND 35-45). Once sexual maturity was reached (PND 70), female rats determined to be either in estrous (sexually receptive) or non-estrous (sexually unreceptive) were exposed to a male target rat, using a paradigm specifically designed to induce sexual motivation while preventing consumatory and/or copulatory behaviors. One hour after the “exposure test” we sacrificed animals in preparation for analysis of c-fos immunoreactivity in hypothalamus, amygdala and nucleus accumbens. We hypothesize that cannabinoid-treated animals will have reduced c-fos expression in sexual motivation-related brain areas and that this functional deficit will only occur during estrous. Using Polarizers in Single Molecule Magnet Mn12 Acetate Terahertz Spectroscopy Xinru Cheng, Chi Yung Fung Professor Beth Parks, Department of Physics and Astronomy, Colgate University As part of a continuous effort at Colgate to study the crystal Mn-12-acetate with terahertz spectroscopy, our project this summer aims at using polarizers to better control the polarization in measurements of transmission, in order to search for relationships between the disorders that cause individual molecules of Mn12-acetate to absorb different photon energies, and the disorders that cause them to exhibit quantum tunneling. The research methodology mainly consists of probing the Mn12-acetate sample, which is aligned with a magnetic field of 7 Tesla and cooled to 4.2K in a cryostat, with THz pulse that goes through three linear polarizers. In order to conserve spin, the crystal sample only absorbs a portion of right circularly polarized (RCP) THz signal while transmitting the left circularly polarized light (LCP), causing the output from the sample to become elliptically polarized. We used wire-grid polarizers to measure the horizontal and vertical components of the sample’s elliptical output. Then we programmed the computer to resolve the signal into transmission graphs for LCP and RCP using a mathematical relationship between linearly and elliptically polarized light. Thus we were able to obtain a more complete picture of the sample’s absorption characteristics. On the absorption versus frequency graphs obtained after Fourier Transform, we expected to see a sharp dip at 300GHz signifying the sample’s absorption of the pulse. Our calculations also predicted the transmission graph of LCP to be significantly bigger than that of RCP. However, after running extensive checks and repeating processes like sample preparation to achieve the best results, we encountered a noise issue during the last week of the project. The noise size was big enough to affect the signal, and we could not account for its source at the moment. Work on this project will be continued in the coming semester by Chi Yung Fung. Biomechanics of S-Looping Kevin T. Chico Professor Ashok Ramasubramanian, Mechanical Engineering Department, Union College, 1.3 million Americans have a congenital heart defect. Abnormal heart looping is a major cause. With the chick embryo as the experimental model, we are studying early s-looping, a stage of heart development when the primitive atria move superior to the primitive ventricle. Our aim is to test the effects of removing the splanchnopleure (SPL) and arresting heartbeat on s-looping. Materials/Methods: Fertilized white Leghorn chicken eggs are incubated to HH Stage 12. For one group, the SPL membrane overlaying the heart is removed through dissection. Another group receives a 1ml solution of 0.8 μM verapamil to stop heartbeat. Both groups and a control group are cultured in an O2-rich environment. Results: Please see Figure 1 Discussion: In c-looping, which directly precedes s-looping, the torsion of the heart tube is delayed by SPL removal, but not stopped. By contrast, the SPL seems to be necessary for early s-looping (Figure1 B,B’ ). An arrested heartbeat has no effect on c-looping. The same seems to be true for early s-looping (Figure 1 C,C’). Are the Catskills Streams Fast or Slug-Like at Retaining Phosphorous? Andrea L. Conine and Sondra M. Lipshutz Professor Catherine A. Gibson, Environmental Studies Program, Skidmore College and Catherine M. O’Reilly, Department of Geology-Geography and Biology, Illinois State University Headwater streams are points of connection between terrestrial landscapes and larger aquatic ecosystems. Due to high physical complexity, shallow depths, and high rates of biological activity, headwater streams are known to have high nutrient processing rates. Nutrient processing is critical to maintaining downstream water quality. Therefore, what controls nutrient uptake in streams is a critical ecological question. We measured nutrient uptake in 14 streams in the Catskills Mountains, NY. At each site, we added a concentrated solution of phosphorous and a conservative tracer and tracked both at downstream location. Biological uptake results in phosphorous retention, but salt is only affected by dilution. Thus, the difference between the two allows us to measure phosphorous retention in the study reach. Ambient phosphorous concentrations ranged from 1-11 μg/L PO4-P. Phosphorous uptake lengths ranged from 15-110 m; indicating high rates of retention. Phosphorus uptake length increased with discharge. Ammonium uptake and phosphorus uptake were highly correlated and this correlation indicates that biological processes are controlling uptake across these sites. From Old Virginia to the Beautiful Blue Danube: Banjo Instruction Methods in Nineteenth-Century America Catherine A. Crone Professor Lydia R. Hamessley, Rare Books and Special Collections Department of Burke Library, Hamilton College The banjo was brought to America in the mid-seventeenth century by West African slaves. However, during the early nineteenth century white musicians began to play banjos, particularly in minstrel shows. The first banjo tutor (musical instruction book), published in 1848, was aimed at these players, but soon authors sought to reach a wider audience, especially middle-class women who could increase the instrument’s respectability; as a result, pedagogical methods, playing styles, and repertoire changed. Hamilton College recently acquired twenty-nine banjo tutors and thirteen other such banjo-related books from the nineteenth and early twentieth centuries. Many are rare; some are unique. All document the musical and social culture of the banjo in America. My paper assesses the various pedagogical methods used in each book, examines playing styles and their contexts, and studies repertoires (classical, minstrel, parlor song, folk). The number of these banjo tutors meant that in-depth exploration of each book was impractical; however, I surveyed the overall collection, noting different pedagogical methods and amassing data (composer, instrumentation, and popularity of each tune) on the vast repertoire. Ichose five of the most significant books to examine fully. I determined that the repertoire shifted from an emphasis on minstrel songs to popular European classical music such as “The Blue Danube Waltz” and excerpts from Il trovatore, partially effected by the shift in playing style from “stroke” to “guitar” style. Further, these tutors used different pedagogical methods in an attempt to provide instruction without a teacher, and I tested these approaches, learning banjo from their books. Finally, I clarified the different roles that each author played in shaping the reception and place of the banjo in American society during the nineteenth and early twentieth centuries. Taylor vs. New Rochelle: Community Distress before the Public Trial Laura A. Dugan Professor Dr. Paul T. Murray, Sociology Department, Siena College Taylor vs. New Rochelle is a little known 1961 school desegregation case oftentimes referred to as the “Little Rock of the North.” Deeply dividing the community of New Rochelle, the case served as a reminder that the South was not the only region beset with the problem of segregation. Since 1930 the concentration of African American pupils and allegations of poor educational standards at Lincoln School had brought accusations of racial segregation. The discontent of Lincoln School parents sparked a community crisis in 1960 following the refusal of the school board to allow Lincoln School students to transfer to other elementary schools within the district. After numerous protests and “stayouts” encouraged by legal counsel Paul Zuber, the case appeared before Federal District Court Judge Irving Kaufman who ruled that Lincoln School had been deliberately segregated. Taylor v. New Rochelle was the first case in which a northern school district was ordered to desegregate. The paper will address the question, “Why did the issue of segregation at Lincoln School become such a pronounced issue in 1960 as opposed to the decades before when controversy first materialized?” The paper will address events during 1960 that resulted in the case going to trial, and focus on how and when the issue of segregation at Lincoln School became prominent. This will involve analyzing various sources collected from the National Archives including the trial transcript, articles and letters to the editor from the New Rochelle Standard Star ̧ as well as interviews with individuals who attended Lincoln School and remember the events that transpired. This paper will explain how the landmark Brown v. Board of Education decision provided legal basis to argue that racial imbalance in Lincoln School was unconstitutionally created, a precedent that did not exist when the issue first was raised. The paper will also explain how the propaganda and publicized “stay outs” initiated by attorney Paul Zuber brought attention to the issue of northern segregation at a time when civil rights was a growing concern throughout the nation. Linking the Distribution of a Noxious Exotic Plant, Alliaria petiolata (Garlic Mustard), and Candidate Dispersal Vectors. Maranda Duval, Charlie Glassberg, Adam Schmelkin Riley Neugebauer, Sustainability Coordinator and Josh Ness, Biology Department and Environmental Studies Program, Skidmore College Invasive species have been identified as a leading cause of habitat degradation worldwide. Garlic mustard, Alliaria petiolata, is recognized as a particularly problematic invader of temperate deciduous forests in the eastern United States and Canada. Unlike more benign exotics, this herbaceous plant is adept at colonizing undisturbed habitats. Once established in those sites, A. petiolata exerts a strong competitive effect on other herbaceous plants and poisons the mycorhizal fungal associates so important to many plant species characteristic of temperate deciduous forests. As a result, A. petiolata is a cause of degradation rather than a symptom. Here, we map the distribution of >15,000 sexually mature A. petiolata plants within a forest on the campus of Skidmore College, and ask what factors might best describe the current distribution of the exotic within the forest. We conclude that 1) A. petiolata is currently confined to several large “super patches” within the forest, 2) these patches are exposed to high traffic (pedestrian, canine, and mechanical) but otherwise do not significantly differ in soil characteristics from noninvaded sites (i.e., these initially invaded sites are distinguished by an unusual degree of propagule pressure, rather than some intrinsic characteristic of the sites), 3) in the absence of further attention, these patches will continue to serve as a source of seed propagules to be transported by foot traffic (pedestrian and canine) deeper into the forest, and 4) that by collecting (killing) these 15,000 plants and mapping the current distribution of A. petiolata (including super patches and nascent “satellite” populations), we have taken a critical first step in protecting the forest from invasion. Studies of Bifunctional Nanotether Influences on CdSe Nanoparticle Stability, Chromophore Distribution and Thin Film Morphology Courtney E. Elwell Professors Joanne D. Kehlbeck, Michael E. Hagerman, Chemistry Department, Union College Solar energy can be harvested via numerous solar cell designs including dye sensitized solar cells and polymer photovoltaics. These third generation nanomaterials offer promises of lower cost and ease in manufacturing. A central focus of alternative energy research seeks to improve photocurrent efficiencies in these systems. Due to their high quantum yield with multiple exciton emissions, wide diameter range, and ability to tune various wavelengths of light emission, CdSe nanoparticles make for promising chromophores for solar cell light absorption and generation of current. The studies conducted this summer focused on generating novel quantum dots containing ligands capable of imparting useful properties to the nanoparticle. The specific ligand studied this summer was 4-aminobenzoic acid and its coordination to the CdSe surface. 1H NMR spectroscopy was used to monitor and quantify ligand exchange. Photophysical properties of the ligands and exchanged CdSe nanoparticles were examined by UV/VIS and fluorescence spectroscopy. Thin films cast with exchanged quantum dots from acidified solvents show promise for minimizing chromophore aggregation. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) imaging were used to characterize thin film morphology. Energy dispersive xray spectroscopy confirmed location of CdSe nanoparticles by identifying elemental signa Leaves of a Flower: A Latvian Woman’s Tale Philip Evangelista Professor Elun Gabriel, History, St. Lawrence University The purpose behind this project was to take the story of my grandmother, Ilga Rozitis, and compare it to other similar stories and put it in the context of history. My grandmother fled Latvia in 1944 and I grew up hearing these stories. The purpose of the project was to see if there were any trends in similar stories and also to put the stories in historical context as best I could. My research consisted of first reading background information on Latvia during World War II and after. Next I read memoirs by other Latvians who fled in the late stages of the war. I also interviewed my grandmother on three different occasions so that I could get the most accurate story that I could. After six weeks of research, I began to write my paper and still continue to work on it today. I anticipate by the finish of my project to have a thirtypage paper, hours of transcribed interviews, photocopied photos and primary documents. Investigation of Invasive Plants in the Hamilton College Forests Daniel Feinberg ’12, Samuel Silverman ’14, Mathew Combs ’13, Ana Fernandez ’13, Dilyana Mihaylova ’12, Bethany O’Meara ’12, Professor William Pfitsch, Department of Biology, Hamilton Several species of non-native invasive plants are prevalent in the forests surrounding Hamilton College in Clinton, NY. In July 2011, we measured the spatial distribution and abundance of five invasive plant species, Alliaria petiolata (garlic mustard);Lonicera japonica (Japanese honeysuckle); Rhamnus cathartica (common buckthorn); Berberis thunbergii (barberry); and Rosa multiflora (multiflora rose), in addition to those of the native Allium tricoccum (wild leek flower). We assigned abundance classes (ranging from 0 to 3) to each of the six species along 100 m x 25 m transects, and mapped the results using ArcGIS, Microsoft Excel, and Adobe PhotoShop. We also began an investigation of soil conditioning by the invasive plants. Whereas many plants condition the soil microbial community to aid in their own growth, invasive plants can culture a microbial community to inhibit the growth of native plants. Using invasive A. petiolata and L. japonica, as well as native Impatiens (jewelweed) and Symphyotrichum prenanthoides (crookedstem aster), in a mixture of non-invaded forest soil mixed 2:1 with perlite, we transplanted multiple seedlings into 25 pots each and allowed them to grow for a period of 10 weeks. We also froze soil samples of the initial conditions for chemical and genetic analysis. This study serves as the foundation for a project that, over the course of at least one year, will assess the aboveand below-ground effects of invasive plants on the native organisms and ecosystem processes of the Hamilton College forests. Deletion of Genes Involved in Copper and Silver Resistance in Cupriavidus metallidurans CH34 Jack A. Fischer, Cheng W. Ng, Sarah M. Minney Professor Sylvia McDevitt, Biology Department, Skidmore College Isolated from a zinc decantation tank in 1976, Cupriavidus metallidurans CH34 harbors resistance to multiple metals, making it an ideal model organism for metalmicrobe interactions. Genome sequencing and annotation identified several gene clusterswhich might be involved in coppers and silver resistance. Two of these clusters, cop and sil are located on one of CH34’s megaplasmids, pMOL30. Using gene replacement, we aim to delete silCBA, copF and the 19 gen containing cop determinant in CH34 and predict an increased sensitivity of the resulting three mutant strains to copper and/or silver ions. The DNA fragments upstream and downstream of copF were successfully cloned into pCM184, flanking a kanamycin resistance cassette and the plasmid is currently transferred into C. metallidurans to replace copF with the antibiotic resistance. For the other two deletions, fragments downstream of cop and silCBA have been successfully cloned into pCM184 and the resulting plasmids are currently used to clone the respective upstream fragments. Once both fragments are in pCM184, the plasmids will be used to knock out the sil or cop determinant in CH34. The mutant strains will be tested for metal sensitivity giving insight into the involvement of these gene clusters in copper and silver resistance in Cupriavidus metallidurans. Dragonfly TSDN Response Time to Simulated Looming Objects Elon Gaffin-Cahn Professor Robert Olberg, Biology Department, Union College Dragonflies have high visual acuity, which, when combined with remarkably fast visual response, allows them to hunt with a high success rate. They do so by intercepting small flies in flight rather than by chasing from behind. Eight bilateral pairs of large Target Selective Descending Neurons (TSDNs) of the dragonfly ventral nerve cord respond to small, contrasting objects, which presumably represent potential prey. These interneurons are part of circuitry that triggers small changes in wing angle and position to control flight during prey interception. In flight, dragonflies extend their legs out to catch the prey about 20 ms before contact. The current research investigates the role of the TSDNs in prey contact. The dragonfly approaching the prey is simulated by generating a growing black circle on a screen. A dorsal approach is used to gain access to the ventral nerve cord. Neural responses of TSDNs are recorded with either tungsten microelectrodes or glass suction electrodes to test if the interneurons can predict the time to contact of the looming stimuli. Anticipated conclusions are that selected TSDNs fire at a consistent interval before the calculated