Digital Commons Network^™

Ultrastructural Analysis Of Excitatory And Inhibitory Synapses Within The Medial Nucleus Of The Trapezoid Body Of Normal Hearing And Congenitally Deaf Mice, Melissa A. Bautista

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The auditory brainstem has been the area of much focus in recent years due to its advantages in circuitry and synaptic connections. The endbulbs and calyces of Held are large, glutamatergic synapses within the AVCN and MNTB, respectively. Because of their large size and accessibility these synapses have offered the ability to study pre- and post-synaptic mechanisms of neurotransmission within the central nervous system. The calyx of Held synapse is the main excitatory input into the MNTB principal cells, containing hundreds of individual synaptic specializations, or release sites. Previous studies have identified physiological and morphological changes at the endbulb of …

Human Immunodeficiency Virus-1 Productively Infects Mature Terminally Differentiated Eosinophils In Hiv/Aids Patients, Jude N. Atem

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Eosinophils express membrane CD4 protein and can bind HIV-1 glycoprotein (gp) 120. Therefore, eosinophils could serve as host cells for HIV-1 infection in vivo, especially in the late phase of the infection. In culture, HIV-1 infects eosinophil precursors and primary eosinophils. Additionally HIV-1 proviral DNA sequences have been detected in the eosinophils of some HIV-1 positive patients. Since elevated levels of eosinophils occur during HIV-1 infection and parasitic infections, it implies that co-infection of parasites and HIV-1 could cause a much greater increase in the level of potential HIV-1 susceptible eosinophils. Therefore HIV-1 infection of eosinophils could partly explain the …

Oxidative Stress And Cell Death In Osmotically Swollen Glial Cells, Crystal Elaine Stuckey

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Regulation of normal volume is an important aspect of cell homeostasis. Possible mechanisms which signal volume regulation are increasing the rate of reactive oxygen species (ROS) production and release of ATP for interaction with purinergic receptors. We examined whether an increase in ROS production during cell swelling also led to cell injury of C6 glioma cells. Cells were loaded with 5,6-carboxy-2,7-dihydrofluorscein diacetate (DCFDA) to fluoroscopically measure the rate of cellular ROS production and were perfused with phosphate-buffered saline solutions (PBS) containing 100 μM carbenoxolone to inhibit dye efflux. Cell death was determined cytometrically and by measuring the release of lactate …

Dynamic Pneumatic Muscle Actuator Control System For An Augmented Orthosis, Maria J. Gerschutz

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This dissertation develops, implements and analyzes a dynamic control system for a pneumatic muscle actuator (PMA) utilizing an augmented orthosis application. The application of PMAs are limited due to poor control capabilities resulting from dynamic nonlinearities. An adequate control system applying an appropriate dynamic pneumatic muscle actuator model increases the potential utility of PMAs in high-force applications including augmented orthotic applications.

The research conducts an initial analysis evaluating the feasibility of PMAs in high-force applications (force assistance with minimal displacement). A computational simulated control system (CSCS) is developed to analyze three different control schemes. The three PMA control schemes (position …

Effects Of Subcutaneous Postnatal Choline Supplementation On Hippocampus-Mediated Learning And Memory In Rat Pups, Jeremy Alan Moore

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The effects of postnatal injections of choline on the acquisition of two variants of eyeblink conditioning were examined in developing Long-Evans rat pups. Choline administration on postnatal days (PND) 15-27 was followed by evaluation of trace eyeblink conditioning (Experiment 1) and delay eyeblink conditioning (Experiment 2) on PND 28-29. The results of these experiments show that choline produced greater improvements in learning and memory during the trace condition than in the delay condition, presumably due to its effect on the hippocampus. Trace eyeblink conditioning relies heavily on an intact hippocampus but delay eyeblink conditioning does not, and it is understood …

The Impact Of Nutrient Availability And Algal Community On Carbon Isotope Fractionaion In Crystal Lake, Clark County, Ohio, April R. Wisebaker

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Crystal Lakes are a group of four interconnected lakes, located in southwestern Clark County, Ohio. Several studies have looked at separate geochemical and isotopic information at this location. However, no one has thoroughly studied the relationship between the algal community, geochemistry, and carbon isotope fractionation within Crystal Lake. The fractionation of carbon isotopes of dissolved inorganic carbonate is greatly affected by the process of photosynthesis; the amount of photosynthesis is affected by the amount of algae in the aquatic community; the amount of algae is affected by the available nutrients in system. Therefore, there should be a correlation between the …

Algorithmic Techniques Employed In The Isolation Of Codon Usage Biases In Prokaryotic Genomes, Douglas W. Raiford Iii

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While genomic sequencing projects are an abundant source of information for biological studies ranging from the molecular to the ecological in scale, much of the information present may yet be hidden from casual analysis. One such information domain, trends in codon usage, can provide a wealth of information about an organism's genes and their expression. Degeneracy in the genetic code allows more than one triplet codon to code for the same amino acid, and usage of these codons is often biased such that one or more of these synonymous codons is preferred. Isolation of translational efficiency bias can have important …

Stress Reducing Effects Of Oxytocin In A Maternal Separation Paradigm, Keely Jane O'Connell

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This study compared the effects of centrally and peripherally administered oxytocin (OT) on HPA axis activity and the presence of both stress-induced active and passive behaviors in female guinea pig pups (Cavia porcellus) after 180-min of isolation . In Experiment 1, one dose of oxytocin (10μg/.2ml) was injected subcutaneously into the periphery. Plasma cortisol levels were reduced after 180-min of isolation and two passive behaviors, eye-closure and crouch, were reduced as well with the administration of oxytocin. In Experiment 2, two different doses (10μg/.2ml and 20μg/.2ml) were injected into the periphery with no significant results. In Experiment 3 one dose …

Sensitization To Trail-Induced Apoptosis In K-Ras 12 Mutant Pancreatic Cancer Cells By Bitc, Christina Ann Wicker

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Pancreatic adenocarcinoma is an aggressive cancer with a greater than 95% mortality rate and short survival after diagnosis. Chemotherapeutic resistance hinders successful treatment. This resistance is associated with mutations within codon 12 of the K-Ras gene (K-Ras 12), which is present in over 90% of all pancreatic adenocarcinomas. Codon 12 mutations maintain Ras in a constitutively active state leading to continuous cellular proliferation. Our study determined if TRAIL resistance in pancreatic adenocarcinomas with K-Ras 12 mutations could be overcome by first sensitizing the cells with Benzyl isothiocyanate (BITC). BITC is a component of cruciferous vegetable extracts and a cell cycle …

Mdm2 Amplification In Nih3t3l1 Preadipocytes Leads To Mdm2 Elevation In Terminal Adipogenesis, Vaughn Litteral

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The p53 protein is a tumor suppressor protein that is mutated or non-functional in nearly all cancers. The Mdm2 protein has the ability to functionally inactivate p53 and these two proteins have been studied extensively in the context of cellular proliferation. In this study, expression of the murine double minute 2 (mdm2) gene was examined in the mouse NIH3T3L1 cell line. Under the proper conditions, the immortalized NIH3T3L1 cells have the ability to differentiate from fibroblasts to adipocytes (Green et al., 1975). This well characterized cell line provides an excellent model to study mdm2 in differentiation. While evaluating the regulation …

The Effects Of Nutritional Supplement, Mass Fx™, On Muscular Strength, Body Composition, And Blood Chemistries In Resistance Trained Adult Males, Patrick S. Dib

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The purpose of this study was to determine the effects of a nutritional supplement, Mass FX, on muscular strength, body composition, and blood chemistries in resistance-trained adult males. Eight subjects, mean age 25 +/- 3.02 years, were randomly assigned to two groups (n=4). Each group was given either Mass FX or a Placebo in a double-blind manner to be taken orally for six weeks (4caps/day regardless of bodyweight). For the duration of the study, both groups were following the same training program and a diet customized to each subject's bodyweight in conjunction to the supplementation. Data were analyzed using Analysis …

Energy Efficient Image Video Sensor Networks, Paul Anthony Bender

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Image Video Sensor Networks are emerging applications for sensor network technologies. The relatively large size of the data collected by image video sensors presents new challenges for the sensor network in terms of energy consumption and channel capacity. We address each of these issues through the use of a high density network deployment utilizing some nodes as dedicated relay nodes.

A high density network allows network nodes to reduce their transmission power. This reduction in transmission power allows each node to conserve power and simultaneously increases the potential for spatially concurrent transmissions within the network, resulting in improved network throughputs. …

Paleoenvironment And Lateral Extent Of An Exposed Carbonate Build-Up: Horry County, South Carolina, Lisa A. Raterink

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A carbonate build-up exposed in the Intracoastal Waterway in Horry County, South Carolina is estimated to be Pleistocene to Pliocene in age. The carbonate build-up discontinuously spans approximately 12 kilometers of the waterway. Prominent formations in the area consist of the Waccamaw and the Canepatch Formation. A distinct sand layer is present laterally between the build-up and the excavated waterway bank, which consists primarily of well preserved fossil molluscs and echinoderms.

Field observations show that the carbonate build-up is bluish-gray in color and composed of shell fragments, predominantly mollusc, in a mud matrix. Thin sections analyzed, using a petrographic microscope, …

Evanescent Microwave Microscopy Of Porcine Skin Tissue, Richard A. Kleismit

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This thesis describes the application of a custom designed λ/4 resonant coaxial probe to measurements of the complex permittivity of in vitro freshly excised porcine skin tissue. The dielectric properties of the organic material within the near field of the tip of the probe frustrates the electric field and measurably changes the resonant frequency and quality factor Q of the coaxial sensor, where the change in resonant frequency and quality factor of a tuned resonance is measured as a function of tip-sample separation. The design of the probe enables better spatial resolution than previously developed probes. The following studies were …

In Search For New P53 Regulated Genes, Meldrick Daniel Mpagi

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The p53 tumor suppressor protein has the ability to transactivate its target genes whose gene products are involved in carrying out cell cycle arrest, apoptosis, DNA repair, and senescence. Here, I report that two genes may be p53 regulated. Utilizing a microarray method to search for novel p53 target genes, I was able to identify a possible transcriptional target of p53 being solute carrier family 1a1 (SLC1a1). Along with that finding I also identified an E2F-target gene, minichromosome maintenance 10 (MCM10), as being p53 regulated. Gene expression profiling of MCF7 breast cancer cells treated with RNAi targeting Hdm2 and HdmX …

Dynamic Characterization Of A Pneumatic Muscle Actuator And Its Application To A Resistive Training Device, Jennifer L. Serres

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Research described in this dissertation expands the use of a biomechanical phenomenological model to a commercially available pneumatic muscle actuator (PMA). Due to the nonlinearities of the device, achieving accurate control is challenging. Experiments have been conducted that define boundaries of operation where linear approximations can be used to describe the dynamics of the PMA. Empirical data presented in this dissertation show that nonlinearities exist more prevalently at higher loads (on average >70% contractile force value). When the PMA is under high loads, low displacement occurs. Therefore, these regions are of less interest to design engineers. Once conditions of nonlinearities …

Availability And Toxicity Of Nickel To Lotic Periphyton And Macroinvertebrates, Stephanie Marie Bessom

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There is a lack of information regarding the bioaccumulation and toxicity of nickel (Ni) to lotic ecosystems. The objective of this study was to investigate the source, uptake, and toxicity of Ni by periphyton and macroinvertebrates (Hyalella azteca and Daphnia magna) in simulated stream ecosystems that included sediment and water. Periphyton were exposed to two types of sediment, a low-organic sandy mixture and a high organic silt, treated with varying levels of Ni. After 96 h, Ni levels in overlying water and periphyton were related to those in sediments, although differences existed between sediment types. Tests with 64Ni added to …

Exploring Team Dynamics: The Evolution Of Coordination In A Complex Command And Control Environment, Daniel H. Schwartz

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The present study explores the dynamic and emergent behavior of two teams, separately working through a synthetic task environment representing a battle management command and control domain under two levels of organizational centralization. While the manipulation of centralization had minimal effects on overall performance, evidence suggested that the need to seek authorization for actions from a central authority was a source of frustration. Both teams adapted over time, changing patterns of coordination to better meet the task demands. The results are discussed in the context of the concepts of normal accidents, high reliability organizations, and self-organization in complex organizations. Specific …

Effects Of Forest Fragmentation And Honeysuckle Invasion On Forest Lepidoptera In Southwest Ohio, Annie Lynn Doyle

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Habitat loss and exotic species invasion is a rapidly growing threat facing forest animal communities worldwide. The goal of the current study is to assess the impact of forest fragmentation and the associated invasion of honeysuckle on immature tree-feeding Lepidoptera communities in southwestern Ohio. Caterpillar abundance, richness, and honeysuckle density were sampled along 100 meter transects conducted in ten forest fragments. Generalized linear models were developed to determine the effects of fragment area, landscape forest cover, and honeysuckle density on caterpillar abundance and richness. Caterpillar abundance and richness was positively related to landscape forest cover and fragment area. However, these …

Automated Analysis Of Metacarpal Cortical Thickness In Serial Hand Radiographs, Aarti Raheja

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To understand the roles of various genes that influence skeletal bone accumulation and loss, accurate measurement of bone mineralization is needed. However, it is a challenging task to accurately assess bone growth over a person's lifetime. Traditionally, manual analysis of hand radiographs has been used to quantify bone growth, but these measurements are tedious and may be impractical for a large-scale growth study. The aim of this project was to develop a tool to automate the measurement of metacarpal cortical bone thickness in standard hand-wrist radiographs of humans aged 3 months to 70+ years that would be more accurate, precise …

Investigating Nickel Flux And Toxicity In Clay Sediments With Batch And Stream Recirculating Flume Experiments, Christina Elizabeth Cloran

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Using batch and stream recirculating flume experiments to compare and contrast one clayey sediment (Warden Ditch) and two analytical grade clay minerals (montmorillonite and kaolinite), the dynamic interactions between two aquatic stressors (suspended solids and nickel) were explored. Aldrich humic acid was incorporated to demonstrate the mitigating effects of dissolved organic carbon (DOC) on Ni toxicity. The flux of Ni between compartments (dissolved and sorbed) was quantified as a partition/distribution coefficient. The USEPA test organism Daphnia magna (neonates, < 24 h) was utilized to evaluate toxicity in dynamic non-renewal, short-term bioassays. Generally, toxicity showed a linear relationship with turbidity level. Conversely, sorption coefficients were experiment specific, making them difficult to predict and assess. Clay functioned as an adsorbent, scavenging Ni. Results support the hypotheses that solids and metals act as stressors in streams, DOC attenuates the toxicity of Ni, and Ni fluxes quickly between system compartments.

The Role Of Phospholipase D (Pld) And Grb2 In Chemotaxis, Katie J. Knapek

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Phospholipase D (PLD) is an enzyme that hydrolyzes phosphatidylcholine yielding choline and phosphatidic acid. PLD is activated by mitogens (lead to cell division) and motogens (leading to cell migration). PLD is known to contribute to cellular proliferation and deregulated expression of PLD has been implicated in several human cancers. PLD has been found to play a role in leukocyte chemotaxis and adhesion as studied through the formation of chemokine gradients. We have established a model of cell migration comprising three cell lines: macrophages RAW 264.7 and LR-5 (for innate defense), and fibroblast COS-7 cells (for wound healing). COS-7 cells respond …

The Community Structure Of Methanogenic, Methanotrophic, And Ammonia Oxidizing Bacteria In Vertical Flow Greenhouse Wetland Mesocosms Exposed To Pce, William Evan Gruner

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Chlorinated ethenes are among the top contaminants on the EPA National Priorities List due to their abundance in contaminated sites and their recalcitrant nature. These compounds, which are used in large scale degreasing and textile processes, are known liver and kidney toxins, and suspected carcinogens. Wetland ecosystems are capable of degrading PCE and its breakdown products TCE, DCE, and VC by providing anaerobic and aerobic growth conditions for microbes that express enzymes such as dehalogenases and monooxygenases with dual affinity for chlorinated solvents. Greenhouse mesocosms at Wright State University are used to mimic field conditions at a treatment wetland at …

Regulation Of Calcium Entry Pathway In Jurkat T Cells, Petronilla A. Fruasaha

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Calcium release-activated calcium channels (CRAC) control influx of calcium in human T lymphocytes. Hour-long calcium elevations are necessary for efficient gene expression during T cell activation and proliferation. We report here that, the time course for store-operated Ca2+ entry is short-lived (3-4 min) and therefore, cannot account for the prolonged Ca2+ elevations necessary for NFAT translocation into nucleus. Previous findings strongly suggest that T cell activation is accompanied by cytosolic alkalinization. Here, we show that pH changes in Jurkat T cells following activation with mitogenic lectin, phytohemagglutinin (PHA), depends on the length of time of exposure and the concentration (potency) …

Multi-Uav Control: An Envisioned World Design Problem, Mona T. Stilson

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Predator Unmanned Aerial Vehicle assets are in high demand in the theater of operations for supporting the Global War on Terror and this demand is expected to increase. This work involved exploratory case study research into the envisioned world design problem of networked Predator multi-UAV control, as a candidate for meeting higher Predator sortie requirements without the need for a one for one increase in pilots. The concept involves the development of a potential new position for controlling multiple UAVs, called the Multi-Aircraft Manager (MAM). The goal was to analyze work requirements and develop representational models of the structure of …

Cenozoic Antarctic Diatomware/Bugcam: An Aid For Research And Teaching, Sherwood W. Wise, M. Olney, J. M. Covington, V. M. Egerton, S. Jiang, D. K. Kulhanek, S. Ramdeen, H. Schrader, P. A. Sims, A. S. Wood, A. Davis, D. R. Davenport, N. Doepler, W. Falcon, C. Lopez, T. Pressley, O. L. Swedberg, David M. Harwood

Department of Earth and Atmospheric Sciences: Faculty Publications

Cenozoic Antarctic DiatomWare/BugCam^© is an interactive, icon-driven digital-image
database/software package that displays over 500 illustrated Cenozoic Antarctic diatom taxa along with original descriptions (including over 100 generic and 20 family-group descriptions). This digital catalog is designed primarily for use by micropaleontologists working in the field (at sea or on the Antarctic continent) where hard-copy literature resources are limited. This new package will also be useful for classroom/lab teaching as well as for any paleontologists making or refining taxonomic identifications at the microscope. The database (Cenozoic Antarctic DiatomWare) is displayed via a custom software program (BugCam) …

New Approaches And Progress In The Use Of Polar Marine Diatoms In Reconstructing Sea Ice Distribution, A. Leventer, L. Armand, David M. Harwood, R. Jordan, R. Ligowski

Department of Earth and Atmospheric Sciences: Faculty Publications

Reconstructing the paleo-latitudinal extent of sea ice in the Southern Ocean over time can be accomplished using modern diatom data. However, it is more difficult to extend the utility of diatom proxies farther back in time, to time periods characterized by species that are now extinct, since we are uncertain of the paleoenvironmental affiliation of those species we can’t observe in modern assemblages. We propose several research strategies to strengthen our ability to use diatom data to reconstruct sea ice history. These tactics include the evaluation of specific morphologic characteristics and distinct taxa, as well as the identification of specific …

Hydrogeochemistry And Water Quality Of Echo Hills, Joel M. Kimball

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Ground water of the Echo Hills area in Clark County, Ohio was investigated for common water contaminants such as nitrate and coliform bacteria. Thirty-four water samples were collected from locations including private wells, streams and a spring. Nine of those samples were selected for nitrogen isotope analysis. Three locations were chosen for a tracer test. Additionally, well log data, historical water quality data, and GIS data were obtained from the Clark County Health Department in Springfield, Ohio. Results show that local agriculture likely has the greatest impact on ground water quality in Echo Hills especially the north-eastern portion, with local …

Memories And Milestones: The Brighton Seminole Tribe Of Florida And The Digitization Of Culture, April Van Camps

Electronic Theses and Dissertations

This dissertation project discusses individual photographs of the Brighton Seminole Tribe of Florida from the early 1900s to the current period, each organized by way of their institutional significance, not their place in chronological history. Following Jean Mohr and John Berger's model in Another Way of Telling, I create a narrative for the pictures with a discussion of historical information, current data from interviews, Tribal members' stories, and my own personal story as it is tethered to the tribe. The research addresses the following questions: Can photography offer a technological means to communicate culture in a vital, organic way? Can …

From Pedagogical Sociology To Constitutional Adjudication: The Meaning Of Desegregation In Social Science Research And Law, Anne Richardson Oakes

Michigan Journal of Race and Law

In the United States following the case of Brown v. Board of Education (1954) federal judges with responsibility for public school desegregation but no expertise in education or schools management appointed experts from the social sciences to act as court advisors. In Boston, MA, educational sociologists helped Judge W. Arthur Garrity design a plan with educational enhancement at its heart, but the educational outcomes were marginalized by a desegregation jurisprudence conceptualized in terms of race rather than education. This Article explores the frustration of outcomes in Boston by reference to the differing conceptualizations of desegregation in law and social science. …