24th Hayes Graduate Research Forum (May, 2010)

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Arts
1st Place: Stanich, Veronica
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2nd Place: Wang, Yang
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Biological Sciences
1st Place: Riley, Maurisa
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2nd Place: Liu, Yu-Yu
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Business
1st Place: Easwar, Karthikeya
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2nd Place: Wynter, Matthew
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Education and Human Ecology
1st Place: Marchionda, Daria
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2nd Place: Pentimonti, Jill
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Engineering
1st Place: Letcher, Todd
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2nd Place: Paquet, Daniel
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Food, Agricultural, and Environmental Sciences
1st Place: Jones, Joseph M.
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2nd Place: Stuckman, Mengling
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Humanities
1st Place: Linder, Kathryn
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2nd Place: Vdovichenko, Susan
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Math and Physical Sciences
1st Place: Kleckner, Ian R.
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2nd Place: Vyas, Shubham
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Professional Biological Sciences
1st Place: Haeussler, David
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2nd Place: Hildreth, Blake Eason III
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Social and Behavioral Sciences
1st Place: McDaniel, Anne
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2nd Place: Workman, Joanna
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Poster Division 1: Arts, Humanities, and Social Sciences
1st Place: Eckerd, Adam
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2nd Place: Jeon, Lieny
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Poster Division 2: Science and Technology
1st Place: Giedt, Randy
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2nd Place: Stuckman, Scott
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Now showing 1 - 20 of 24

PTHrP 1-141 and 1-86 Increase In Vitro Bone Formation
(Elsevier in the Journal of Surgical Research, 2010-05) Hildreth III, Blake Eason; Rosol, Thomas; Toribio, Ramiro
Background—Parathyroid hormone-related protein (PTHrP) has anabolic effects in bone, which has led to the clinical use of N-terminal fragments of PTHrP and PTH. Since 10-20% of fractures demonstrate healing complications and osteoporosis continues to be a debilitating disease, the development of bone-forming agents is of utmost importance. Due to evidence that regions of PTHrP other than the N-terminus may have bone-forming effects, this study was designed to compare the effects of full-length PTHrP 1-141 to N-terminal PTHrP 1-86 on in vitro bone formation. Materials and methods—MC3T3-E1 pre-osteoblasts were treated once every 6 days for 36 days with 5, 25, and 50 pM of PTHrP 1-141 or 1-86 for 1 or 24 hours. Cells were also treated after blocking the N-terminus, the nuclear localization sequence (NLS), and the C-terminus of PTHrP, individually and in combination. Area of mineralization, alkaline phosphatase (ALP), and osteocalcin (OCN) were measured. Results—PTHrP 1-141 and 1-86 increased mineralization after 24-hr treatments, but not 1-hr. PTHrP 1-141 was more potent than 1-86. Treatment with PTHrP 1-141 for 24-hr, but not 1-86, resulted in a concentration-dependent increase in ALP, with no effect after 1-hr. Exposure to both peptides for 1- or 24-hrs induced a concentration-dependent increase in OCN, with 24-hr exceeding 1-hr. Antibody blocking revealed that the NLS and C-terminus are anabolic. Conclusions—Both PTHrP 1-141 and 1-86 increased in vitro bone formation; however, PTHrP 1-141 was more effective. The NLS and C-terminus have anabolic effects distinct from the Nterminus. This demonstrates the advantage of PTHrP 1-141 as a skeletal anabolic agent.
SPECT Imaging for Temporal Dynamics of Thyroidal and Salivary Radionuclide Accumulation in 17-AAG Treated Thyroid Cancer Mouse Model
(2010-05) LIU, YU-YU; Jhiang, Sissy M.
Selective iodide uptake and prolonged iodine retention in the thyroid is the basis for targeted radioiodine therapy for thyroid cancer patients, however, salivary gland dysfunction is the most frequent non-thyroidal complications. In this study we employed non-invasive SPECT functional imaging to quantify the temporal dynamics of thyroidal and salivary radioiodine accumulation in mice. At 60 min post radionuclide injection, radionuclide accumulation in the salivary gland was generally higher than that in thyroid due to much larger volume of the salivary gland. However, radionuclide accumulation per anatomic unit in the salivary gland was lower than that in thyroid and was comparable among mice of different age and gender. Differently, radionuclide accumulation per anatomic unit in thyroid varied greatly among mice. The extent of thyroidal radioiodine accumulation stimulated by a single dose of exogenous bovine TSH (bTSH) in T3-supplemented mice was much less than that in mice received neither bTSH nor T3 (non-treated mice), suggesting that the duration of elevated serum TSH level is important to maximize thyroidal radioiodine accumulation. Furthermore, the extent and duration of radioiodine accumulation stimulated by bTSH was less in the thyroids of the thyroid-targeted RET/PTC1 (Tg-PTC1) mice bearing thyroid tumors compared to the thyroids in wild type mice. Lastly, the effect of 17-AAG on increasing thyroidal, but not salivary, radioiodine accumulation was validated in both wild type mice and Tg-PTC1 preclinical thyroid cancer mouse model.
The Effects of Hyaluronic Acid on Canine Posterior Lens Capsule Opacification In Vitro
(2010-05) Haeussler, David Jr.; Chandler, Heather; Gemensky-Metzler, Anne
Purpose: Posterior capsular opacification (PCO) is the most common complication following cataract surgery. During PCO formation, residual lens epithelial cells undergo posterior migration and proliferation. During dynamic cellular events such as inflammation and wound repair, hyaluronic acid (HA) interacts with cell surface receptors and can induce cellular migration and proliferation. HA is one of the components found in the viscoelastic agents commonly used intraoperatively during cataract surgery. The introduction of exogenous HA in the form of viscoelastics during cataract surgery may promote lens epithelial cell migration and thus contribute to PCO formation. Based on these observations the purposes of this research were 1) to confirm that HA receptors are present in the canine lens and 2) to determine if the rate of lens epithelial cell migration and proliferation is altered following treatment with HA. Methods: Canine lens epithelial cells from normal (n=12) and cataractous (n=12) lenses were evaluated using immunohistochemistry and RT-PCR for expression of CD44 and CD168. Two in vitro models of PCO were used to determine if various HA concentrations altered lens epithelial cell migration and proliferation. In the first model, a one millimeter scratch was created in cultures of confluent canine lens epithelial cells. Cells were treated with 0, 0.2, or 1.0 mg/mL (n=6) of HA dissolved in unsupplemented DMEM. Migration of lens epithelial cells into the scratch was monitored over 24 hours and quantified using ImageJ (available from the National Institutes of Health). In the second model, mock cataract surgery was performed on canine cadaver eyes. Following removal of lens fibres, capsules were re-distended and remaining lens epithelial cells were incubated with one of the following treatments (n=6): no viscoelastic (DMEM only), 0% HA viscoelastic (contains hydroxypropyl methylcellulose), 1.2% HA viscoelastic, or 2.0% HA viscoelastic. Treatment remained in the capsule for 5 minutes before removal by irrigation and aspiration. Capsules were monitored daily and the rate of migration and proliferation onto the posterior capsule was evaluated by counting all LEC adhered to the capsule in sequential H&E histologic sections. RT-PCR for CD44 and CD168 was performed on samples from both in vitro models of PCO. Results: Both normal and cataractous lens epithelial cells were positive for CD44 and CD168 protein and mRNA. In the first model of PCO, there was a significant increase in the rate of migration and proliferation in lens epithelial cells treated with 0.2 and 1.0 mg/mL of HA compared to lens epithelial cells receiving 0 mg/mL of HA (p = 0.001). Following treatment with both 0.2 and 1.0 mg/mL HA, there was an increase in CD44 and CD168 mRNA expression. In the second model of PCO, lens epithelial cells treated with either 1.2% or 2.0% HA-containing viscoelastics reached confluence on the posterior capsule significantly faster than lens epithelial cells receiving no or 0% HA viscoelastic (p=0.003). Expression of CD44 and CD168 was higher in capsules receiving HA-containing viscoelastic compared to controls, as determined by RT-PCR. Implications: Cataract is the most common cause of vision impairment in both dogs and humans, and surgery is currently the only accepted method for eliminating cataracts and related vision loss. PCO occurs in up to 50% of adult humans; in canine patients and pediatric humans, the incidence of PCO approaches 100%. This research demonstrates that canine lens epithelial cells possess the appropriate receptors to respond to HA signaling. Treatment with various HA concentrations increased the rate of lens epithelial cell migration, proliferation, and expression of CD44 and CD168. In addition, acute exposure to viscoelastics containing HA significantly increased the rate of PCO in vitro. The introduction of exogenous HA in the form of viscoelastics during cataract surgery may promote lens epithelial cell migration and thus contribute to PCO formation in vivo. These results may help both human and veterinary ophthalmologists determine which viscoelastics should be used intraoperatively to decrease the prevalence of PCO.
From Brownfields to Greenfields: Assessing the Environmental Justice of Cleaning Up Brownfields
(2010-05) Eckerd, Adam; Keeler, Andy
Issues of environmental injustice in siting of environmental hazards are well known. Based on past research, the expectation is that lower socioeconomic status populations are systematically subject to higher levels of environmental risk in their communities. In this paper, I investigate whether similar patterns appear prevalent in environmental improvement as well. First, I assess the characteristics of the communities in which brownfield sites are currently located. Then, I compare the likelihood and prioritization of cleaning up brownfield sites based on the composition of their neighborhoods. I find that while sites in communities with larger minority populations are likely to move at a slower pace through the initial assessment phases of the cleanup process, they are no less likely to ultimately be cleaned up. I suggest that economic and political considerations are better explanations of this result than overt discrimination.
Examining Upper and Lower Case Letter Knowledge with Item Response Theory
(2010-05) Pentimonti, Jill; Justice, Laura
Children’s alphabet knowledge is among the strongest predictors of children’s early literacy skills (Scarborough, 1998) and is a key component of emergent literacy development (Whitehurst & Lonigan, 1998). Alphabet knowledge is typically conceptualized as total number of letters a child knows (i.e., a simple sum score). Therefore, the fact that some letters are more likely to be known than others (i.e., inter-letter differences) is not taken into account in alphabet knowledge assessments. However, research studies suggest that specific alphabet knowledge does vary in acquisition (McBride-Chang, 1999), indicating that researchers and educators should consider inter-letter differences in alphabet knowledge. In addition, some experts contend that there are potential inter-letter differences between upper and lower case letters. Sophisticated measurement techniques, such as those based on Item Response Theory (IRT), allow for a more nuanced and precise understanding of alphabet knowledge through explicitly modeling potential inter-letter differences. The purpose of the present study was to use IRT to further identify inter-letter patterns in children’s acquisition of alphabet knowledge, and thus provide insight for alphabetic assessment and instruction.
Post-transcriptional Regulation of Lfng by miR-125a is Crucial for Vertebrate Segmentation
(2010-05) Riley, Maurisa; Cole, Susan
Somites are the embryonic precursors of vertebrae, ribs, and skeletal muscles. They form from the presomitic mesoderm (PSM) by a periodic segmentation process called somitogenesis. The periodic budding of somites is controlled in part by the oscillatory expression of genes such as Lunatic fringe (Lfng), a modulator of Notch signaling, which function in a segmentation clock that times somitogenesis. Proper clock function requires that both the mRNA half-lives of oscillatory genes and the translational efficiency of these transcripts be tightly controlled during the rapid time period of the clock. We propose that microRNAs (miRs) have a conserved function in the segmentation clock through post-transcriptional regulation of oscillatory genes. We demonstrate that Lfng is a conserved target of two miRs (miR-125a-5p and miR-200b) enriched in the PSM, where the segmentation clock is active. Blocking interactions between one of these miRs (miR-125a-5p) and Lfng in developing chick embryos abolishes oscillatory gene expression of endogenous Lfng and cHairy1, resulting in disrupted somite formation and patterning. These findings suggest that miR:transcript interactions may modulate the oscillatory expression of clock-linked genes by affecting mRNA turnover and/or translational efficiency. The data presented in this paper provide the first evidence supporting a role for miRs in the segmentation clock and enhance our understanding of post-transcriptional regulation of oscillatory genes.
Small Scale Wind Turbines Optimized for Low Wind Speeds
(2010-05) Letcher, Todd; Shen, Herman
A combination of common vertical axis wind turbines (VAWT) rotors was designed and tested for optimal performance in low wind speeds. The Savonius rotor creates high torque and is self-starting even at low wind speeds, but is relatively low in efficiency rating. The Savonius rotor is used to start the straight bladed Darrieus rotor. The Darrieus rotor is not a self starting rotor, but has much higher efficiency than the Savonius rotor. The combination of rotors increases the total power of the turbine in lower wind speeds.
The Global 3-Dimensional Structure of Climate Associated with the Atlantic Multidecadal Oscillation
(2010-05) Stuckman, Scott; Lin, Jialin
The Atlantic Multidecadal Oscillation (AMO) is a dominant driver of climate on multidecadal timescales characterized by alternating cool and warm phases that disguise and enhance the effects of global warming respectively. Despite this, some climate models remain unable to generate a realistic AMO-like signal, prompting the UN Intergovernmental Panel on Climate Change (IPCC) to target the AMO as a research priority that will make significant contributions to the upcoming Fifth Assessment Report. This study uses a global climate reanalysis database covering 60 years (one full AMO cycle) to regress a number of climate variables (e.g., temperature, precipitation, pressure and winds at various altitudes) onto an AMO index in order to reconstruct the climate effects of the AMO. The goals of this study are to advance a better understanding of the AMO and its effects on climate, reveal global teleconnection patterns and provide a high-quality reconstruction of AMO-related climate that can be used as a benchmark for the improvement of climate models via ‘hindcasting’. Improved climate forecasts in turn have significant implications (e.g., extension of drought and monsoon forecasts beyond the current seasonal timescales) and provide opportunities for more informed societal decision-making (e.g., better long-term water management strategies and more appropriate agricultural planning in affected areas).
Effects of Home Environment and Preschool Childcare Quality on Early Cognitive and Social Skills
(2010-05) Jeon, Lieny; Buettner, Cynthia
Realizing a number of children in early childhood are not sufficiently prepared to enter school, this study was designed to examine and improve contextual features of the home and preschool environment for school readiness. Little research has explored the association between household chaos and children’s development of cognitive skills and social competence. Additionally, as several states in the US have launched state government-funded “Quality Rating and Improvement System (QRIS)” to improve the quality of early childhood education, an evaluation of the system was needed. The current study examined the links among household chaos, QRIS quality, and children’s cognitive and social skills, using a sample of 4844 parents with a preschool age child from 568 QRIS rated preschool programs in Ohio. Analysis revealed that a disorganized and chaotic home environment was a significantly unique risk factor of a child’s social competence after controlling for the child age, gender and family SES. There was little evidence of QRIS influences on child cognitive skills and social competence, and no significant moderating effect of QRIS between the relationship of household chaos and child outcomes; however, this study guided future research on QRIS and home environment. Finally, this study emphasized the importance of early childhood intervention and prevention programs for young children’s school readiness.
Temporal Changes in Gene Transcription of Salmonella Typhimurium Induced by Pulsed Electric Field
(2010-05) Jones, Joseph M.; Yousef, Ahmed E.
Pulsed electric field (PEF) is a novel food processing technology that promises to deliver safe foods with increased quality by inactivating potentially harmful microorganisms while generating a minimum thermal effect. The engineering aspects of this technology have been thoroughly studied and as a result, PEF is now feasible for commercial application. However, the mechanism of microbial inactivation via PEF is still unclear and must be resolved before the technology can be approved for commercial use. Theories of the mechanism of microbial inactivation of PEF via membrane disruption have been suggested but specific cellular targets have yet to be elucidated. The purpose of this study is to examine temporal changes in the transcriptome of PEF treated Salmonella Typhimurium LT2 in order to elucidate the molecular basis for cellular inactivation. This knowledge will allow for more directed efforts to increase the killing efficiency of PEF and aid in the development standardized processing procedures for use in the food industry. Briefly, Salmonella Typhimurium LT2 ATCC 19585 was inoculated into 5% strength tryptose soy broth (TSB), with electrical conductivity of 1.2 mS/m, and incubated at 32°C for 18-22 h with shaking at 150 rpm. This was followed by two additional passages of the inoculum under identical conditions. The final culture was collected at mid-log phase (7.3–7.5 log cfu/mL) for treatment. Cells of the final culture were treated with a PEF processor (OSU-4ERRC) using a predetermined treatment that produced a 1-log cfu/mL reduction in cell population as determined by the plate count method on tryptose soy agar (TSA). The treatment conditions were: square wave, bipolar pulse, 25.6 kV/cm electric field, 3 μs pulse width, 1 ms delay time, and 3 mL/s flow rate, giving a total treatment time of 91 μs. The temperature of the treated culture was maintained at 30-32°C with cooling before the first chamber, after the second chamber, and after the fourth chamber, via cooling coils submerged in a circulating water bath. RNA of treated cells was extracted at 0 (control), 3, 30, and 60 min post treatment and used to produce labeled complementary DNA (cDNA) via Reverse Transcriptase PCR (RT-PCR). cDNA from opposing samples was labeled for comparison with either or Cy3 and Cy5 and opposing samples were competitively hybridized to a Salmonella microarray slide (Pathogen Functional Genomic Research Center Salmonella Typhimurium, Version 5) containing four replicates of each Salmonella open reading frame. The slides were manually washed and scanned at 10 μm spot resolution. Image and data analysis were performed using the TIGR TM4 software suite; specifically, Spotfinder v. 3.2.1 for image analysis, MIDAS v. 2.21 for data normalization, and Multiple Experiment Viewer (MeV) v 4.5.1 for statistical analysis and gene clustering. Data processing included spots identification using the Otsu algorithm, LOWESS normalization of spot intensities, standard deviation regularization, flip dye cross-slide replicate analysis, and in-slide replicate analysis. ANOVA between time points was performed using Pearson correlation distance metric with p=0.02 and fold change of 1.5 was used as the arbitrary cutoff ratio. All slides were duplicated and fold change of all samples was determined with respect to the 0 min. sample. A total of 560 genes, representing ~2% of the genes in the Salmonella genome showed a significant difference in transcription between samples, and of these 276, representing ~1% of the genome had a fold change of ≥ 1.5. Genes related the DNA damage induced SOS response were prevalent among those unregulated at 30 and 60 min post treatment. These included genes of the rec, umu, din, uvr, and rtc operons, which are responsible for DNA damage repair and mutagenesis. Genes in the wca, yjb, and psp operons, which are associated with stress to the cell envelope and are responsible for exopolysaccharide production, showed a transient increase in transcription at 30 min post treatment. Flagellar synthesis genes in the fli and flg operons showed a transient decrease in transcription at 30 min post treatment. Patterns of transient gene expression, which include genes mainly involved in maintenance of components of the cell envelope, suggest damage to cell membranes. This agrees with previous reports of the cellular inactivation mechanism attributed to PEF, especially the temporary nature of the damage as implied by the transient up regulation of response and repair genes. Sustained increase in the transcription of SOS genes suggests that cells also experience significant DNA damage as a result of PEF processing. The up regulation of SOS genes may also explain the reports of a recovery period post PEF processing during which damaged cells are viable, but non-recoverable. It is unclear as to whether DNA damage is a direct result of the applied electric field, or if DNA damage occurs indirectly, due to influx of damaging materials into the cell during the time that membrane integrity is reduced. The function of many genes remains to be investigated and most are expected to be related to the DNA and envelope damage repair pathways. However, due to the large number of genes yet to be investigated in this study, it is likely that additional cellular targets of PEF will also be identified. As the full scope of cellular components affected by PEF is realized, methods for increasing the treatment’s effectiveness against undesirable bacteria in foods will be more readily determined.
An integrated material characterization-multiscale model for the prediction of strain to failure of heterogeneous aluminum alloys
(2010-05) Paquet, Daniel; Ghosh, Somnath
Aluminum cast alloys and metal matrix composites are widely used in automotive, aerospace, nuclear and other engineering systems due to their advantageous strength/density properties. Their microstructure is characterized by a dispersion of hard and brittle heterogeneities in a softer aluminum matrix. The distribution, shape, and size of these heterogeneities affect their failure properties like fracture toughness and ductility in an adverse manner. Important micro-mechanical damage modes that are responsible for deterring the overall properties include particulate fragmentation, debonding at interfaces and ductile matrix failure due to void initiation, growth and coalescence. To address the needs of a robust methodology for ductility, a comprehensive model for deformation and failure of ductile materials integrating both a material characterization and a multiscale computational model has been developed. The material characterization is used as a preprocessor to the multiscale model and is an important step for the incorporation of microstructural features in predictions of strain to failure. The capabilities of the integrated material characterization-multiscale model are demonstrated for a cast aluminum alloy.
Evaluating the Release of Arsenic from Drinking Water Absorbents under Regulatory and Landfill Leaching Conditions Using X-ray Adsorption Fine Structure (XAFS) Spectroscopy
(2010-05) Stuckman, Mengling; Lenhart, John
Due to its known toxic and carcinogenic effects, the presence of arsenic in drinking water is currently regulated in the United States at a level of 10μg/L. In order to meet regulatory needs and protect public health, single-use adsorbents are utilized to remove arsenic in most water systems in the US. Consequently, when saturated with arsenic, an estimated 10,000 tons of arsenic bearing solid residuals (ABSRs) from drinking water treatment systems will be discarded into landfills every year. However, arsenic may be concentrated and released into landfill leachate. If improperly treated, released arsenic may cause secondary pollution to the discharged water bodies, some of which can be drinking water reservoirs, resulting in possible ecological or human health concerns. Most ABSRs have been shown to pass regulatory leaching tests which determine their eligibility to be disposed of into a municipal landfill. However, existing evidence suggests that regulatory leaching tests failed to simulate the actual landfill conditions potentially favorable for arsenic release, such as elevated pH, reducing conditions, presence of competitive anions and complex natural organic matter (NOM) that could dissolve the minerals comprising the adsorbent. Therefore, it is crucial to investigate the mechanism of arsenic release, especially information of surface binding transformation that directly determines As leachability from the ABSRs under different leaching conditions. This research, therefore, represents one of the first studies utilizing both traditional chemical analysis and x-ray adsorption fine structure (XAFS) spectroscopy to evaluate As binding structures in ABSRs from long-term full-scale operations and associated binding strength differed from geographically diverse sources. Furthermore, this study also aims at providing direct binding transformation evidence to investigate leaching conditions favorable for As release. Our results show that the coexistence of weaker As binding structures is usually an indicator of less effective adsorption during drinking water treatment confounded by source water or treatment processes, such as less operation time, manganese coating and insufficient pH adjustment. Higher initial As loading would lead to larger As release in subsequent landfill disposal. Thus, drinking water facilities should consider the balance between the effective As treatment of the media and disposal cost in the future as the legislation tightens. Our results also presented no binding transformation after leaching tests at lower pH and transformation from stronger binding to weaker bindings as pH increases in the leaching condition. This could be utilized to directly support the idea that current leaching tests are not sufficient enough to simulate As release in landfill conditions with respect to elevated pH. TCLP was also shown to misrepresent the potential carbon-promoted iron dissolution or carbon competition with As on iron surface which would facilitate As release. The iron dissolution is found to be one of main contributors to As release in many recent studies.
Photoperiodic Regulation of Affective Responses and Hippocampal Cell Morphology in Siberian Hamsters
(2010-05) Workman, Joanna; Nelson, Randy
Seasonal affective disorder (SAD) is characterized by depressive episodes during winter that are alleviated during summer and by morning bright light treatment. Currently, there is no animal model of SAD. However, it may be possible to use rodents that respond to day length to understand how day length can shape brain and behavior in humans. For instance, Siberian hamsters use day length to time seasonal cycles of reproduction and also exhibit changes in nonreproductive behaviors dependent on day length. Specifically, short-day Siberian hamsters increase floating in the forced swim test (a behavioral test used to screen antidepressant compounds). Current research in depression and animal models of depression suggests that hippocampal atrophy may underlie the symptoms of depression and depressive-like behaviors, respectively. The goal of this study was to determine whether altered depressive-like responses after exposure to short days are associated with photoperiod-mediated plasticity within the hippocampus of Siberian hamsters. Hamsters were housed in either short (8:16 LD) or long days (16:8 LD) for 10 weeks. At the end of 10 weeks hamsters were tested in the forced swim test and 48 h later, brains were removed and stained using the Golgi impregnation method. Brains were processed for hippocampal dendritic length, branching, and spines, as well as cell body size. Short days significantly reduced cell body size and dendritic complexity in the CA1 region of the hippocampus. This suggests that altered depressive-like behavior induced by exposure to short days may be a consequence of reduced complexity (and perhaps connectivity) in the hippocampus.
Analysis of Mitochondrial Morphology in Cells Experiencing a "Heart Attack"
(2010-05) Giedt, Randy; Alevriadou, Rita
Vascular endothelial cell (EC) dysfunction immediately following the recanalization of a blocked artery (known as reperfusion, RP) is attributed to the cellular generation of superoxide radicals and other reactive oxygen species (ROS). Nitric oxide (NO) is known to promote ROS production from the cell mitochondria. Our lab discovered that cultured EC exposure to fluid mechanical shear stress results in endogenous NO-mediated mitochondrial ROS production. Ischemia (I)/RP-induced EC injury occurs primarily due to mitochondrial ROS production, and the decline in bioavailable NO (due to the reaction of NO with superoxide) impairs the EC-dependent dilation in the heart coronary vessels. In general, mitochondrial ROS lead to activation of the mitochondrial apoptotic pathway. Recent literature suggests that induction of mitochondrial apoptosis correlates with mitochondrial fragmentation (fission), which may contribute to cell apoptosis/death. Our goals are to detect and quantify changes in mitochondrial morphology due to cultured EC exposure to simulated I/RP (with or without inhibitors of ROS sources, a NO synthase inhibitor or an inhibitor of the mitochondrial fission protein Drp1), and to determine whether these changes contribute to cell apoptosis/death. Following cultured EC exposure to treatments, such as fluid shear stress, hypoxia/reoxygenation (H/RO) or ischemia/reperfusion (I/RP; ischemia is simulated as hypoxia; reperfusion is simulated as reoxygenation with the addition of flow), ECs are stained with mitotracker green, which is used in conjunction with fluorescence microscopy to obtain digital images of the mitochondrial network. Morphological parameters are determined for each object in an image, and these are used for quantitative comparisons of the mitochondrial network between treatments. We found that static or sheared ECs maintain their mitochondrial network. H/RO-exposed ECs undergo changes in mitochondrial morphology, but fission is significantly less compared to that in ECs exposed to I/RP. The massive fission in I/RP-exposed ECs is inhibited by antioxidants, a NO synthase inhibitor or a Drp1 inhibitor. Hence, ROS, NO and Drp1 are all responsible for the I/RP-induced increase in mitochondrial fission. Mitochondrial morphology changes may be implicated in the induction of EC apoptosis after vessel recanalization following a heart attack suggesting that, by controlling mitochondrial morphology, we may be able to lessen the EC dysfunction and improve outcomes.
Reconsidering the Judson influence
(2010-05) Stanich, Veronica; Bales, Melanie
This paper investigates the relationship between the audience and contemporary dance that bears the clear influence of the Judson Dance Theater, a group of dancers and other artists who made dance and theatre work in New York in the early 1960s. Current dance practices still show the influence of many of the Judson artists' innovations. However, the ground-breaking dance practices of the Judson Dance Theater were relatively isolated within an elite group of artists in downtown New York, and this isolation has implications for the current status of contemporary dance in America. Whereas the aesthetic of ballet and modern dance was brought into the awareness of the American public by such means as Hollywood and Broadway musicals, non-theatrical venues such as the union halls where the Workers' Dance League performed, and the near-celebrity visibility of its practitioners such as Martha Graham, the Judson aesthetic had no such machinery for exposure. As such, that aesthetic as it is manifested in contemporary dance is largely unfamiliar and often bewildering to the public at large. Appreciation and enjoyment of Judson-inflected contemporary dance requires knowledge of the work of the Judson Dance Theater-its theoretical base and its art-historical context-and is therefore only available to a circle of dance "insiders."
Donut dynamics: localized allosteric activation and ligand-binding kinetics in the ring-shaped ligand-responsive regulatory protein TRAP
(2010-05) Kleckner, Ian R.; Foster, Mark P.
The overarching goal of this research is to gain insight into mechanisms of ligand-modulated gene regulation by studying the trp RNA-binding Attenuation Protein (TRAP). TRAP is a biological Trp-sensor endogenous in bacilli: when cellular free Trp concentration is low, TRAP predominates in the inactive apo form and the micro-organism may synthesize additional Trp using a specific molecule of RNA. However, when the Trp concentration rises TRAP may bind this excess Trp and thus become activated to bind that RNA molecule. When TRAP binds the RNA, it disables downstream production of additional Trp. Thus, the micro-organism employs TRAP in this simple feedback mechanism to ensure that it will only synthesize Trp if it is scarce. The goal of the current study is to rigorously and quantitatively examine the details of TRAP activation which occur upon Trp-binding using two distinct approaches: (1) NMR spectroscopy is used to probe the structure and dynamics of TRAP. This study quantifies μs-ms molecular dynamics present in apo TRAP which are hypothetically required for proper function. Upon Trp-binding, there are quantifiable changes in both the structure and dynamics of TRAP. Importantly, the protein appears to rigidify at the μs-ms timescale. (2) Stopped-flow fluorescence spectroscopy is used to investigate the time course of Trp binding upon rapid mixing with apo TRAP. These data reveal not one, but two kinetic steps interpreted as (a) Trp-binding which occurs slower than the diffusion limited rate, followed by (b) conformation exchange of TRAP between two distinct states. These data also indicate formation of bonds, increase in order and compression of TRAP structure upon binding. These investigations help Biologists to understand TRAP at a mechanistic level. They are also of broad interest towards rigorously quantifying the time-dependent behavior of any ligand-responsive protein (many of which are essential for life).
The Fall of Lehman: Cross Country Comovement during the Crash of October 2008
(2010-05) Wynter, Matthew; Stulz, Rene
Using the recent Credit Crunch as a global fixed point for international financial markets, this study investigates how the collapse of Lehman, treated as an exogenous shock to the U.S. financial market, caused an increase in international equity market comovement. Using a sample of 47 FTSE equity markets, the study explores how comovement between the US and international markets evolved during the Crash of October 2008. Consistent with predictions of contagion, I find strong evidence of increased comovement when controlling for market fundamentals.
Russia Constructed: the Practice of Avant-gardism in Taisho-era Japan, 1912-1926
(2010-05) Wang, Yang; Andrews, Julia
While Japan's artistic and cultural exchanges with Western Europe, especially France, have been thoroughly vetted, such a dialogue with Eastern Europe, especially Russia, deserves more scholarly attention. The geographical proximity of the two nations points to a rich and sustained history of exchange, but a comprehensive study of the Russo-Japanese exchange from an art-historical perspective remains to be undertaken. This void in scholarship testifies to the weight of political history in shaping art-historical discourse. Because Japan after World War II aligned itself with nations of the Western sphere, its cultural ties to Russia have been neglected. An examination of the Japanese art world in the early twentieth century reveals that Russian modernist practices significantly affected the development of the Japanese avant-garde through numerous points of contact, both brief and sustained, from the 1910s to the 1930s.
Borderlanguage: Language Policy, Ideology and Identity in Ukraine
(2010-05) Vdovichenko, Susan; Isurin, Ludmila
Language and identity are inextricably intertwined, and language policy directly impacts people's lives for more than just communication. In Ukraine, after nearly a century of widely varying linguistic policies and customs, Ukrainian was declared the sole official language in 1991. Almost two decades later, language issues remain critical in politics, perhaps because of the link between language and identity, and complicated by linguistic ideology. In part because of its early history, Ukrainian had been perceived by many as only suitable for village use and regarded as substandard. However, Ukrainian is now the only official language of education and government. This transition has been difficult for some, particularly those who may feel that their identity as Russian-speakers is being attacked; in many parts of Ukraine, negative stereotypes about Ukrainian and its speakers remain. At the same time, a strong connection has been forged between the Ukrainian language, Ukrainian culture, and national pride, and attitudes toward Ukrainian by Russian speakers are changing. Preliminary online research showed that underlying negative attitudes towards Ukrainian permeate many circles, and this paper looks at the results of surveys and interviews conducted by the author in Simferopol, Kherson, Kyiv, and Kharkiv, Ukraine, to tease out stereotypes, examine speaker correlations, and better understand the changing situation. Specifically, data is analyzed for types of stereotypes that persist, and how these stereotypes play across age and geographical region. Motivations for such stereotypes are explored, and connections between language policy, identity, language ideology, and language attitudes are sought out. Determining how, why, and for whom the linguistic transition is the most difficult helps to shed light on what factors influence successful language policy implementation, as well as how language ideology affects the lives of Ukrainians today.
Family Therapy Retention: An Observation of First Session Communications
(2010-05) Marchionda, Daria; Slesnick, Natasha
This study focused on the relationship between communication patterns and dropout rates among families (n = 12) receiving family systems therapy. Families were considered treatment completers if they attended 12 sessions (n = 6) and dropouts if they attended 1-3 sessions (n = 6). Audiotape recordings of the first therapy session were transcribed and coded. The total percentage of communications by the parent, adolescent, and therapist was measured and the content of each communication was coded (positive, negative or neutral). Parents (but not adolescents) within families that completed therapy showed higher talk time proportions than parents in families that dropped out of therapy. In addition, completer families had higher percentages of therapist-to-parent communications while dropout families had higher percentages of therapist-to-adolescent communications. These findings demonstrate the potential utility of examining within session communication patterns and suggest that certain processes, especially parental communication involvement, may determine whether or not a family returns for treatment.

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