Digital Commons Network^™

Dimethylmercury Production In Freshwater Sediments, David C. Kelly

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Dimethylmercury (DMHg) has been examined almost exclusively in marine environments to date, plays an uncertain role in the global cycling of Hg, and is produced by a currently unknown mechanism in natural systems. We examined DMHg production in microcosms containing 100 cm3 of freshwater sediment sampled from 3 wetlands and a lake near Dayton, Ohio. DMHg was produced from all sediments analyzed, and found that production is increased significantly by the addition of inorganic Hg from ~0.1pM to ~10pM, its production is unaffected by autoclaving the sediment, and organic carbon additions had no discernible effect on production. Its total concentrations …

Surface Modification Of Carbon Structures For Biological Applications, Elizabeth Irene Maurer

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Carbon substrates have a wide variety of applications, many of which are enabled by appropriate surface modifications. In particular, the use of carbon-based substrates for biological devices can be quite advantageous due to their relative inertness and biocompatibility. Moreover, graphitic carbon can take many forms ranging from flat sheets to foams, fibers, and nanotubes. In this project, larger carbon substrates such as microcellular foam and flat graphite have been modified with carbon nanotubes, and their potential use in two types of biological applications was tested. The first study involved an investigation of the growth and proliferation of osteoblast cells on …

The Im-9 Cell Line: A Model For Evaluating Tcdd-Induced Modulation Of The Polymorphic Human Hs1,2 Enhancer Within The 3' Immunoglobulin Heavy Chain Regulatory Region, Ruth C. Chambers-Turner

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2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a disrupter, of B-cell differentiation, induces binding of the aryl hydrocarbon receptor (AhR) nuclear complex to dioxin responsive elements (DRE) within the mouse immunoglobulin heavy chain regulatory region (3'IgHRR), and produces a marked inhibition of 3'IgHRR activation, IgH expression, and antibody secretion in a well-characterized mouse B-cell line (CH12.LX). The mouse 3'IgHRR consists of at least four enhancers (hs3a; hs1,2; hs3b; hs4), and is highly homologous with the three enhancers (hs3; hs1,2; hs4) of the human 3'IgHRR. A polymorphism of the human hs1,2 enhancer (resulting in varying numbers of tandem repeats containing a DRE and κB site) has …

Thermal And Electrochemical Characterization Of Cathode Materials For High Temperature Lithium-Ion Batteries In Ionic Liquids, Jodie R. Shoaf

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Finding a cathode material to operate a high-temperature Li-ion battery in the presence of an ionic liquid has become an attractive area of research. Three cathode materials, LiCoO2, Li4Ti5O12, and LiFePO4, were received from Electrochemical Systems Inc. of Knoxville, TN. Three ionic liquids were synthesized using a 1-alkyl-3-methylimidazolium (XMI+) cation, where the alkyl group was either ethyl, pentyl or hexyl, and contained a bis(pentafluoroethylsulfonyl)imide (Beti-) anion. The thermal and electrochemical properties of each ionic liquid, of each cathode material, and each combination of cathode material in the presence of ionic liquid were studied. All of the ionic liquids were found …

The Role Of Apoptosis In Hela Cells Expressing Hiv-1 Rev, Elizabeth Page

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The HIV protein Rev is a nucleolar protein that regulates late gene expression in infected cells by promoting the export of under-spliced viral RNAs (Pollard and Malim, 1998). Its over-expression can also inhibit progression through mitosis (Miyazaki et al., 1995), possibly through its ability to depolymerize microtubules (Watts et al., 2000). Consequently, Rev may activate the spindle assembly checkpoint in mitotic cells and increase the frequency of apoptosis. Rev also binds the nucleolar protein B23 involved in ribosome maturation and centrosome duplication. Because loss of B23 function stimulates apoptosis (Ahn et al., 2005), Rev expression may promote apoptosis by inhibiting …

Exploration Using Reaction Temperature To Tailor The Degree Of Order In Micro-Block Copolymer Proton Exchange Membranes, John Quentin Buquoi Iii

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The ability to control the self-assembly of sulfonated poly(arylene ether) sulfones (s-PAESs) was explored by tailoring rate coefficients, via temperature, in an A₂ + B₂ + B₂' Nucleophilic Aromatic Substitution (S_NAr) approach. The reactivity of various electrophilic sites were studied and tuned, via temperature control, to elicit a range of more ordered and disordered polymers of equivalent monomeric composition. These polymers were characterized by ¹H and ¹³C NMR spectroscopy and found to have highly disordered polymer configuration at higher temperatures while having a more regular configuration at lower temperatures.

The Effect Of Expertise And Cognitive Demand On Temporal Awareness In Real-Time Scheduling, James Samuel Garrett

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The following study examines the relationship between amount of information, performance, expertise, and temporal awareness during a high fidelity military battle command simulation. The current study provides an in situ example of temporal estimation which is lacking in the current body of research. Twenty Ohio National Guardsmen of varying expertise played the role of battle commander during the simulation. Novice behavior differed from experts. Novice indications of temporal awareness did not vary with contextual change. However, they provided non-detailed temporal utterances and a relationship between temporal awareness and performance. This pattern suggests that they were overwhelmed by the amount of …

Induction Of P53 Dependent Cellular Senescence Through Hdmx Inhibition Or Ypel3 Expression, Kelly Lynn Robbins Miller

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Mutations in p53 that compromise its function have been reported in approximately half of all human cancers (Vousden et al., 2002). The other half of human tumors that retain wild-type p53 have a dysfunctional p53 pathway through other mechanisms (Wade et al., 2009). Activation of p53 leads to cell cycle arrest, DNA repair, apoptosis and senescence, however, the pathway leading to cellular senescence is the focus of this study. Cellular senescence is a process leading to irreversible arrest of cell division. Under normal physiologic conditions, the activity of p53 is kept in check by its negative regulators, Mdm2 and MdmX. …

Surveillance In A Smart Home Environment, Ryan Stewart Patrick

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A system for assisting the elderly in maintaining independent living is currently being designed. When mature, it is expected that this system will have the ability to track objects that a resident may lose periodically, detect falls within the home, and alert family members or health care professionals to abnormal behaviors.

This thesis addresses the early stages of this system's development. It presents a survey of the work that has previously been completed in the area of surveillance within a home environment, information on the physical characteristics of the system that is being designed, early results related to this system, …

P63 And Vdr Are Regulated By Vitamin D (Vd3) And Uv Signaling, Andrew J. Whitlatch

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Skin cancers, such as squamous cell carcinoma (SCC), develop from accumulated mutations as a result of excessive exposure to Ultraviolet B (UVB) radiation. Intriguingly, UVB also catalyzes the synthesis of 1alpha, 25-dihydroxy Vitamin D3 (VD3), the hormonally active form of Vitamin D. Downstream VD3 signaling has been associated with promoting the inhibition of cell cycle progression, regulating calcium homeostasis, and inducing differentiation and apoptosis. VD3 mediates these processes via genomic mechanisms through interaction with its cognate receptor, the Vitamin D Receptor, (VDR). In addition, it was recently discovered that VD3 reduces UVB-mediated phosphorylation of the SAPK/c-Jun N-terminal kinase (JNK), which …

Development Of A Remote Medical Image Browsing And Interaction System, Wei Ye

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In this thesis a new capability - remote image browsing built upon our existing music telepresence platform is introduced. The implementation of this new image capability has two parts: one part is the local image viewing and the other part is distributed image-view interaction. Image viewing part is realized using the foundation of Linux GTK+ library. Most popular lossless and lossy image coding formats such as GIF, PNG, BMP and JPEG are supported currently. Image viewing part also provides several image operations such as: zoom in and zoom out, image information display and moreover users can select their own regions …

Dammed And The Damned: Draining The Bucket Dry, Carla Steiger

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This thesis investigates how people displaced from the construction of large dams in seek environmental justice. I studied the importance of regime type, the creation of protest groups and the formation of alliances with national, international organizations, and the media. In a comparison between protest movements against the Three Gorges Dam in China and the Sardar Sarovar Dam in India, displaced populations suffered from loss of community, livelihood, and health and were victimized by corrupt actors that supported the dams. The rapid economic development of these two countries emerged as a major point of comparison between the two. Regime type …

Electrochemical Deposition Of Molybdenum And Tungsten From Trinuclear Metal Clusters (M3O2(Oac)6(H2O)3(Cf3So3)2) In 1-Ethyl-3-Methylimidazolium Tetrafluoroborate Ionic, Charles Woods

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Electrochemical properties of Mo₂WO₂(O₂CCH₃)₆(H₂O)₃(CF₃SO₃)₂ and W₃O₂(O₂CCH₃)₆(H₂O)₃(CF₃SO₃)₂ clusters in 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIBF₄) ionic liquid was investigated. Cyclic voltammograms using a platinum electrode indicated that deposition of metal had occurred. Constant potential electrolysis of Mo₂WO₂(O₂CCH₃)₆(H₂O)₃(CF₃SO₃)₂ at -1.9 V using a platinum foil electrode …

The Effects Of The Mennonite Church Usa On Enrollment In Mennonite Institutions Of Higher Education, Katherine Anna Steiner

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The purpose of this study was to determine if enrollment at Mennonite institutions of higher education was impacted after the Mennonite Church (MC) USA formed in 2002. There are five Mennonite institutions of higher education in the United States: Bethel College in Kansas, Bluffton University in Ohio, Eastern Mennonite University in Virginia, Goshen College in Indiana, and Hesston College in Kansas. This parallel mixed methods study identified how the merger of the MC USA impacted the overall enrollment at Mennonite IHE. In addition, it explored enrollment based on gender, race, or Mennonite affiliation.

For the quantitative method of this research, …

Impact Of Culture And Age On The Use Of Social Networking Websites, Ramya Reddy Ponnavolu

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Social networking websites have become very popular amongst people of all ages in recent times. These websites have brought into existence a new form of data - 'User generated content'. Companies everywhere have begun to identify the potential of these sites and have commenced efforts to take advantage of the profitable opportunities available. In spite of all this, it is reasonable to say that the latent possibilities in social networking sites are yet to be fully explored. This is due to the fact that the technology is still young and research on its potential is still ongoing. The current research …

Respiratory-Gated Imrt Quality Assurance With Motion In Two Dimensions, Michael Todd Massie

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Intensity modulated radiation therapy (IMRT) plans can be further customized to each patient with the use of a four-dimensional (4D) respiratorygated computed tomography (CT), with time being the fourth dimension. The 4D respiratory-gated CT allows for the internal margin (IM), the expansion of the tumor volume that accounts for physiologic motions, to be addressed in the treatment planning process and no longer assumes that the treatments will be delivered to a fixed or rigid patient anatomy. Delivering the IMRT plan with a gated technique limits the treatment to a duty cycle when the target motion is at a minimum.

The …

Prognosis: A Wearable System For Health Monitoring Of People At Risk, Alexandros A. Pantelopoulos

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Wearable Health Monitoring Systems (WHMS) have drawn a lot of attention from the research community and the industry during the last decade. The development of such systems has been motivated mainly by increasing healthcare costs and by the fact that the world population is ageing. In addition to that, RandD in WHMS has been propelled by recent technological advances in miniature bio-sensing devices, smart textiles, microelectronics and wireless communications techniques. These portable health systems can comprise various types of small physiological sensors, which enable continuous monitoring of a variety of human vital signs and other physiological parameters such as heart …

Dosimetric Effects Near Implanted Vascular Access Ports Under External Electron Beam Radiation, David Coll Segarra

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Previous studies on dosimetry show important effects for metal vascular access ports for x-rays and electron beams and moderate to no effects for plastic ports for x-ray beams when ports are in the path of the beam. No previous studies exist regarding the effects of electron beams on vascular access ports other than for those made of metal although it has been suggested that electron beam attenuation through non-metal ports may be possible.

Measurements of relative ionization through the device and adjacent to the device anteriorly and laterally were taken. A clinical particle accelerator delivered typical clinical electron beams of …

Character Education: The Effects Of An After-School Music Program On At-Risk Youth Student Motivation And Academic Achievement, Sharon L. Koster

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This case study was designed to increase student motivation and improve academic achievement in at-risk students through participation in an after-school music program. The case study began in September 2007, as a part of Project Jericho's After-school Arts Program, a program that is a collaboration between the Clark State Community College Performing Arts Center and Job and Family Services of Clark County, in Springfield, Ohio. An analysis compared pre and post data that included field notes, personal observation, student journals, and SWIS data (School-wide Information System: official school behavioral tracking system for data), in order to measure changes in behavior, …

Tissue Specific Effects Of Adipose Stem Cells (Asc) In A Melanoma Tumor Environment, Drew Michael Nedderman

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This study determined the tissue-specific effect of adipose stem cells (ASC) within a melanoma environment for development of a cell-based melanoma therapy. Analysis included a subcutaneous B16-F1 melanoma model using thirty-one C57BL/6 wild-type mice. Melanoma xenografts were treated with cell-based therapies of CFDA-SE-labeled human fibroblasts HF20x (control), non-differentiated ndASC or hematopoietic-differentiated HdASC. No tumor regression was observed in presence of cell-based therapies, thus, the HdASC group demonstrated an increase in tumor growth accompanied with an up-regulated macrophage response, and increased angiogenesis. In addition, this group demonstrated a decrease in Melan-A tumor marker and interferon-γ expression suggesting that ASC-supported tumor angiogenesis …

Biodegradation Of Groundwater Pollutants (Chlorinated Hydrocarbons) In Vegetated Wetlands: Role Of Aerobic Microbes Naturally Associated With Roots Of Common Plants, Christina Lynn Powell

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Chlorinated aliphatic hydrocarbons (CAHs) are often found as groundwater contaminants because of past industrial activities and disposal practices. CAHs pose a threat to human health and thus, create a need to find both natural and engineered processes that can remove these chlorinated compounds from the environment. Natural attenuation by oxidative biodegradation is especially important because it can allow for mineralization to carbon dioxide, a nontoxic end-product. The goal of this research was to evaluate the potential oxidative biodegradation of CAHs by microorganisms that are naturally associated with wetland plant roots. The research was divided into field work and laboratory batch …

Charaterization Of Chlorpyrifos Toxicity On The Pancreatic Beta Cell Line Rinm5f, Zhongyu Yan

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Chlorpyrifos (CPF) is a well-known organophosphate (OP) insecticide that inhibits acetylcholinesterase (AChE). Organophosphates have been shown to induce hyperglycemia in both humans and animals that cannot be explained by AChE inhibition alone. Pancreatic β-cells are responsible for secreting insulin and playing a fundamental role in glucose homeostasis. The aim of this research was to investigate CPF toxicity on the insulin secreting β-cell line RINm5f (RIN). In the first part of this dissertation, we determined that cytotoxic concentrations of CPF between 50 µM and 200 µM induced a dose-dependent increase in RIN cell apoptotic and necrotic death (p<0.05). Lower doses, i.e., 5-25 µM did not induce apoptosis or necrosis. In further mechanistic studies, inhibitors of c-Jun N-terminal kinase (JNK) and P38 pathways, i.e., SP600125 and SB202190, successfully attenuated CPF-induced apoptosis (p<0.05), suggesting cell death is mediated by JNK and/or p38. In addition, N-Acetyl-L-cysteine (NAC), an antioxidant, inhibited apoptosis suggesting that oxidative stress is also involved in RIN cell death. In the second part of this dissertation, low dose CPF's effects on insulin synthesis and secretion was studied. Our results showed that RIN cells treated with CPF for 4 hr exhibited a dose-dependent decrease in insulin secretion in response to stimulation by 50 mM potassium (p<0.05). Insulin secretion stimulated by 25 mM glucose also showed significant decreases upon incubation with various doses of CPF (p<0.05). Insulin synthesis involves proteolytic cleavage of proinsulin at two specific sites. The enzymes responsible for promoting proinsulin cleavage, i.e, prohormone convertase (PC) 1/3 and 2 (PC2), contain a serine hydrolase catalytic triad, His-Asp-Ser, similar to AChE. CPF modification of PC enzymes similar to AChE, could potentially interrupt the conversion of proinsulin to insulin and disrupt insulin secretion. PC2 enzyme activity was significantly inhibited by CPF at concentrations as low as 10 µM (p<0.01). RIN cells, for the first time, were found to secrete proinsulin was through a constitutive instead of a regulated pathway. In summary, our results show that CPF not only exerts a direct cytotoxic effect at concentrations above 50 µM, but also significantly impairs insulin secretion at lower doses. Low dose CPF could potentially affect endocrine function in vivo by inhibiting the proinsulin processing enzyme PC2.

Inhibition Of Cell Invasion By Targeting Pld, Terry C. Farkaly

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Phospholipase D (PLD) is a crucial signaling enzyme involved in many cellular processes. The catalytic activity of PLD is essential for the production of Phosphatidic Acid (PA), a critical second messenger in cell signaling cascades downstream. Using the highly invasive rat mammary adenocarcinoma cell line mTLn3 as a metastatic model, we investigated the proficiency of these cells to invade using matrigels that mimic the basement membrane of the extracellular matrix (ECM), their activity through PLD enzymatic assays, as well as the potency of our potential inhibitors to inhibit PLD-mediated cell invasion and lipase activity. This study reveals that PLD-mediated cell …

Rev Interacts With Tubulin Heterodimers To Cause Cell Cycle Defects, Poornima Kotha Lakshmi Narayan

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Rev is a regulatory protein that plays an important role in the replication of HIV virus by post-transcriptionally promoting expression of viral proteins late in infection. Rev expression also slows cell growth, leads to an accumulation of cells in G2/M specifically before the spindle checkpoint, and can produce changes in ploidy. Because Rev is capable of depolymerizing microtubules (MTs) in vitro, possibly by a mechanism shared with Kinesin-13 proteins, themselves potent cellular MT depolymerases, I tested the hypothesis that these cellular defects were due to an interaction between Rev and tubulin.

To this end, Rev and select Rev mutants defective …

The Influence Of Stored Product Mites On The Function Of Skin Microvascular Endothelial Cells, Jennifer Graff Curp

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The prevalence of allergenic diseases and sensitization to stored product mites is increasing worldwide. Stored product mites are prevalent in homes, foods, and some work environments. Stored product mites need to be further studied so we can characterize their inflammatory properties to understand their role in skin disease, and provide proper treatment to patients with mite allergies. The purpose of the study was to show the role of stored product mites in modulating the inflammatory and immune response to human dermal endothelial cells in the skin. The epidermis serves as the first line of defense between the body and the …

Transport Through Georeservoirs: Spatial Entropy In Hydraulic Properties, And Temporal Entropy In Residence Time Distributions, Lumeng Huang

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The general principle of maximum entropy can be used to guide the construction of flow and transport models parameters when are uncertain. The principle states that the model which maximizes the entropy should be chosen so that the full multiplicity or uncertainty is represented in the model outcomes.

In models for flow and transport through georeservoirs, the principle would commonly be applicable to the uncertainty in the model outcome for the time of travel through the system, in order to represent the full range of multiplicity in the distribution of residence times. Importantly, the model which maximizes the entropy in …

Electrochemical Oxidation Of Ethanol In Ionic Liquids And Its Possible Use In Fuel Cells, Ashley M. Mason

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Electrochemical properties of EtOH in EMImBF4 ionic liquid were investigated and compared to the electrochemical properties of EtOH in 0.1M HClO4/H2O. As was shown earlier, oxidation of EtOH in HClO4/H2O involves formation of PtO on the electrode surface, which makes the electrode poisoned. We have found that the best procedure for removal of PtO from the Pt electrode is heating the electrode in concentrated H2SO4. Cyclic voltammograms obtained after cleaning several Pt electrodes conforms that this treatment gives clean Pt electrodes without any PtO. Electrochemical oxidation of EtOH in EMImBF4 ionic liquid show that is poisoning of Pt electrode by …

Uncertainty Quantification Of Residual Stresses Induced By Laser Peening Simulation, Hemanth Amarchinta

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Advanced mechanical surface enhancement techniques have been used successfully to increase the fatigue life of metallic components. These techniques impart deep compressive residual stresses into the component to counter potentially damage-inducing tensile stresses generated under service loading. Laser Peening (LP) is an advanced mechanical surface enhancement technique used predominantly in the aircraft industry. To reduce costs and make the technique available on a large-scale basis for industrial applications, simulation of the LP process is required. Accurate simulation of the LP process is a challenging task, because the process has many parameters such as laser spot size, pressure profile, and material …

Estimating Permeability From The Grain-Size Distributions Of Natural Sediment, Lawrence Mastera

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Permeability, k, can be estimated using the Kozeny-Carman equation, given a grain-size distribution with any number of grain-size categories and the porosity of a sediment. A recursive method was developed to calculate the effective grain-size parameter, d, for sediment mixtures with more than three grain sizes. The method was tested on four sediment models of sand, gravelly sand, sandy gravel, and open-framework gravel created from grain-size distributions. The k estimated from the recursive method were consistent with physical measurements of k.

Inferring Lake Depth Using Diatom Assemblages In The Shallow, Seasonally Variable Lakes Of The Nebraska Sand Hills (Usa): Calibration, Validation, And Application Of A 69-Lake Training Set, Avery L. C. Shinneman, Danuta M. Bennett, Sherilyn C. Fritz, Jens Schmieder, Daniel R. Engstrom, Aris Efting, John Holz

Department of Earth and Atmospheric Sciences: Faculty Publications

The Nebraska Sand Hills are a distinctive eco-region in the semi-arid Great Plains of the western United States. The water table underlying the Sand Hills is part of the High Plains/ Ogallala aquifer, an important water resource for the central Great Plains. Lake levels are affected directly by fluctuations in the water table, which is recharged primarily by local precipitation and responds quickly to climatically induced changes in regional water balance. Instrumental records are available for only 50–100 years, and paleolimnological data provide important insights into the extremes and variability in moisture balance over longer time scales. A set of …