Digital Commons Network^™

Bisphosphonates And Bone Microdamage, William A. Caruthers

Theses and Dissertations--Biomedical Engineering

Osteoporosis is a significant healthcare issue due to the increasing elderly population. Bisphosphonates are used to treat osteoporosis by reducing the rate of resorption, increasing bone mineral density (BMD) and thereby reducing fracture risk. Long-term bisphosphonate treatment, however, has been associated with low-energy fractures. Bone microdamage may provide a partial explanation for one of the mechanisms responsible for these fractures since it has been shown to reduce bone toughness, fracture resistance, and bone strength. The goal of this study was to quantify the changes in bone microdamage parameters with the duration of bisphosphonate treatment. This study selected, stained, and histomorphometrically …

Identifying Hot-Spots Of Fecal Contamination In The Royal Spring Karstshed, Samuel C. Lee

Theses and Dissertations--Civil Engineering

The City of Georgetown, Kentucky relies on a vast karst spring network as a drinking water source. This karst feature has several inputs from sinkholes and streams in the Cane Run Watershed: a watershed associated with a variety of land uses in the recharge area. The recharge area encompasses the area from North Lexington to Georgetown and is composed of urban, suburban, agricultural and industrial usage. A serious water quality issue exists with respect to the impact of fecal contamination within the spring recharge area. Identification of fecal contamination is quantified by microbial indicators adapted from surface water applications: fecal …

Noninvasive Assessment And Modeling Of Diabetic Cardiovascular Autonomic Neuropathy, Siqi Wang

Theses and Dissertations--Biomedical Engineering

Noninvasive assessment of diabetic cardiovascular autonomic neuropathy (AN): Cardiac and vascular dysfunctions resulting from AN are complications of diabetes, often undiagnosed. Our objectives were to: 1) determine sympathetic and parasympathetic components of compromised blood pressure regulation in patients with polyneuropathy, and 2) rank noninvasive indexes for their sensitivity in diagnosing AN. Continuous 12-lead electrocardiography (ECG), blood pressure (BP), respiration, regional blood flow and bio-impedance were recorded from 12 able-bodied subjects (AB), 7 diabetics without (D0), 7 with possible (D1) and 8 with definite polyneuropathy (D2), during 10 minutes supine control, 30 minutes 70-degree head-up tilt and 5 minutes supine recovery. …

Functionalized Silica Materials And Mixed-Matrix Membranes For Environmental Applications, Noah Daniel Meeks

Theses and Dissertations--Chemical and Materials Engineering

Functionalized silica materials are synthesized for various environmental applications. The overall objective is functionalization with sulfur-containing moieties for mercury sorption and as a platform for nanoparticle synthesis. The first objective is quantifying this functionalization for various silica platforms. The second objective is development of effective mercury sorbents, for both aqueous mercury and elemental mercury vapor. Third, those sorbents are incorporated into mixed matrix membranes (MMM) for aqueous mercury sorption. Fourth, functionalized silica materials are developed as platforms for the synthesis of reactive metal nanoparticles (NP) for the degradation of trichloroethylene.

Thiol-functionalized silica is used as a sorbent for aqueous mercury, …

Creating Heaven On Earth: Jim Bakker And The Birth Of A Sunbelt Pentecostalism, Eric G. Weinberg

Theses and Dissertations--History

This dissertation traces the rise of Jim and Tammy Bakker and analyzes the birth and growth of prosperity theology in the United States of America. It highlights how Jim and Tammy created a form of Pentecostalism that grew alongside and because of the growth of the Sunbelt. It blossomed in the new suburban enclaves of this region. Jim Bakker's religious ideas had their roots in an increasingly powerful anti-New Deal coalition that was led by the conservative business community. Positive thinking and the prosperity gospel reinforced their beliefs in unfettered markets and their opposition to activist government. Bakker combined these …

Central And Peripheral Regulation Of Circadian Gastrointestinal Rhythms, Jaclyn Malloy

Theses and Dissertations--Biology

Circadian clocks are responsible for daily rhythms in gastrointestinal function which are vital for normal digestive rhythms and health. The present study examines the roles of the circadian pacemaker, the suprachiasmatic nuclei (SCN), and the sympathetic nervous system in regulation of circadian gastrointestinal rhythms in Mus musculus. Surgical ablation of the SCN abolishes circadian locomotor, feeding, and stool output rhythms when animals are presented with food ad libitum, while restricted feeding reestablishes these rhythms temporarily. In intact mice, chemical sympathectomy with 6- hydroxydopamine has no effect on feeding and locomotor rhythmicity, but attenuates stool output rhythms. Again, restricted …

The Biology And Management Of Brucellosis In Yellowstone Bison, John Joseph Treanor

Theses and Dissertations--Biology

Disease management along the boundaries of wildlife reserves is a growing conservation problem worldwide, as infected wildlife can migrate outside protected areas and pose a threat to livestock and human health. The bison Bison bison population in Yellowstone National Park has long been infected with Brucella abortus, the bacterium causing bovine brucellosis. Concern over migratory bison transmitting B. abortus to cattle herds on lands adjacent to Yellowstone has led to proposals for bison vaccination. Model simulations suggest that vaccination is unlikely to eradicate B. abortus from Yellowstone bison but could be an effective tool for reducing the level of …

What Rocks The Vote? Citizens' Views Of Community Leaders And Political Engagement, Cecil J. Shelton

Theses and Dissertations--Community & Leadership Development

Political engagement has an established body of research. However, one key area that has not been investigated in the field is the relationship between political engagement and type of community lived in. This study explores this relationship between type of community, past political engagement, perceptions of community leaders, attitude about political engagement, and socieodemographic characteristics. A conceptual model was developed based on existing literature. Utilizing a statewide survey conducted in 2009 that yielded 1,154 respondents with a response rate of 30.2% was used to explore these relationships. Using statistical procedures that test correlation were utilized to investigate the relationship between …

Male Farmers Coping With Loss Of Spouse: Impacts On Farming Operation And Family Life, Daniel O. Wilson

Theses and Dissertations--Community & Leadership Development

Losing a spouse is as devastating an experience anyone will ever deal with in his or her life. Research, however, shows that men have a harder and longer time coping with the loss of a spouse than women. When the widower’s profession is farming, there are no resources to specifically help that individual with their loss. The purpose of this research was to gain insight into the lives of widowed farmers with particular focus on transitions in their farming operation and their family life. Through their stories, we learn what is happening before the loss of the female spouse on …

Evaluating The Effectiveness Of Weep Berm Systems For Treating Runoff From A Horse Muck Composting Operation, Ross L. Guffey

Theses and Dissertations--Biosystems and Agricultural Engineering

Two contour weep berms systems were designed and implemented to evaluate their performance at mitigating water quantity problems from a horse muck composting operation. The field-scale study focused on the hydrologic response of a standard contour weep berm and a modified contour weep berm. The modified contour weep berm incorporated a woodchip trench upgradient of a typical standard contour weep design. Monitoring occurred from July 2011 through spring 2012. Eight storm events produced measureable runoff for the standard contour weep berm; however, only five storm events produced measurable runoff for the modified contour weep berm. The largest storm event occurred …

Investigating The Role Of Prion Protein Polymorphisms On Prion Pathogenesis, Eri Saijo

Theses and Dissertations--Microbiology, Immunology, and Molecular Genetics

Transmissible spongiform encephalopathies (TSEs), also known as prion diseases, are lethal and infectious neurodegenerative diseases of humans and animals. The misfolding of the normal, or cellular isoform of the prion protein (PrP^C) into the abnormal disease-associated isoform of PrP (PrP^Sc) could change the properties of PrP, consequently, PrP^Sc has lethal infectivity to transmit diseases. The proteinaceous infectious particle consisting mainly of PrP^Sc is called prion. Transmissibility of prions is strongly influenced by multiple factors including PrP polymorphisms, species barriers (PrP sequence specificity) and prion strains (conformational specificity) by unknown mechanisms. Even though the ability …

Role Of The Immune System And Bioactive Lipids In Trafficking Bone Marrow-Derived Stem Cells In Patients With Ischemic Heart Disease, Ahmed Abdel-Latif

Theses and Dissertations--Microbiology, Immunology, and Molecular Genetics

Acute myocardial infarction (AMI) triggers the mobilization of stem/progenitor cells from bone marrow (BMSPCs) into peripheral blood (PB). The underlying mechanisms orchestrating this mobilization and subsequent homing of BMSPCs to the myocardium are poorly understood. While the role of traditional chemokines in the mobilization and homing of hematopoietic stem cell (HSCs) to BM niches is undisputed, their role in directing BMSPCs to the highly proteolytic environment of the ischemic myocardium is debatable and other redundant mechanism may exist. Based on our observation that bioactive lipids, such as sphingosine-1 phosphate (S1P) and ceramide-1 phosphate (C1P), play an important role in regulating …

Disruptions In The Regulation Of Extracellular Glutamate In The Rat Central Nervous System After Diffuse Brain Injury, Jason Michael Hinzman

Theses and Dissertations--Neuroscience

Glutamate, the predominant excitatory neurotransmitter in the central nervous system, is involved in almost all aspects of neurological function including cognition, motor function, memory, learning, decision making, and neuronal plasticity. For normal neurological function, glutamate signaling must be properly regulated. Disrupted glutamate regulation plays a pivotal role in the acute pathophysiology of traumatic brain injury (TBI), disrupting neuronal signaling, initiating secondary injury cascades, and producing excitotoxicity. Increases in extracellular glutamate have been correlated with unfavorable outcomes in TBI survivors, emphasizing the importance of glutamate regulation.

The aim of this thesis was to examine disruptions in the regulation of extracellular glutamate …

Dynamic L-Glutamate Signaling In The Prefrontal Cortex And The Effects Of Methylphenidate Treatment, Catherine Elizabeth Mattinson

Theses and Dissertations--Neuroscience

The prefrontal cortex (PFC) is an area of the brain that is critically important for learning, memory, organization, and integration, and PFC dysfunction has been associated with pathologies including Alzheimer’s disease, schizophrenia, and drug addiction. However, there exists a paucity of information regarding neurochemical signaling in the distinct sub-regions of the PFC, particularly the medial prefrontal cortex (mPFC). The mPFC receives glutamatergic input from a number of brain areas, and functional glutamate signaling is essential for normal cognitive processes. To further understand glutamate neurotransmission, in vivo measurements of glutamate were performed in the cingulate cortex, prelimbic cortex, and infralimbic cortex …

Regulation Of Hepatic Gene Expression During Liver Development And Disease, Hui Ren

Theses and Dissertations--Microbiology, Immunology, and Molecular Genetics

My first project was to investigate the role of Hepatocyte Nuclear Factor 1 (HNF1) and Nuclear Factor I (NFI) on alpha-fetoprotein (AFP) promoter activity during liver development. AFP is highly expressed in the fetal liver, silenced at birth, and remains at very low levels in the adult liver. A GA substitution located at -119 of the human AFP promoter is associated with hereditary persistence of AFP (HPAFP) expression in the adult liver (Hum Molec Genet, 1993, 2:379). The -120 region harbors overlapping binding sites for HNF1 and NFI. While it has been shown that the GA substitution increases HNF1 binding, …

Blast-Induced Brain Injury: Influence Of Shockwave Components, Dexter V. Reneer

Theses and Dissertations--Neuroscience

Blast-induced traumatic brain injury (bTBI) has been described as the defining injury of Operations Enduring Freedom and Iraqi Freedom (OEF/OIF). Previously, most blast injury research has focused on the effects of blast on internal, gas filled organs due to their increased susceptibility. However, due to a change in enemy tactics combined with better armor and front-line medical care, bTBI has become one of the most common injuries due to blast. Though there has been a significant amount of research characterizing the brain injury produced by blast, a sound understanding of the contribution of each component of the shockwave to the …

Signaling Mechanisms Involved In The Generation Of Human Peripheral Itregs, Mary Catherine Reneer

Theses and Dissertations--Microbiology, Immunology, and Molecular Genetics

Maintaining balance in the human immune system is critical for the body’s ability to discriminate between foreign and self-antigens. This balance is achieved, in part, by a subpopulation of T cells known as induced regulatory T cells (iTregs). Dysregulation of this population may contribute to the onset and progression of cancer, chronic inflammation and autoimmune diseases. Therefore, manipulation of iTreg development holds promising therapeutic potential; however, studying this vital population has proven difficult due to low numbers, heterogeneous cell populations, substantial phenotypic differences between mouse and human cells, and the high plasticity seen in iTregs. These current limitations have prevented …

Crosstalk Between Gastrointestinal Epithelial Cells And Resident Microbiota Promotes Immune Homeostasis, Eric William Rogier

Theses and Dissertations--Microbiology, Immunology, and Molecular Genetics

The gastrointestinal tract houses one of the most dense and diverse communities of bacteria on the planet. The mutualistic relationship between the host and commensal microbe permits the microbe an ideal environment to grow and provides the host with increased caloric intake, maturation of the adaptive immune system, and resistance against invading pathogens. To maintain a system in which both parties benefit, the epithelium has evolved numerous strategies to ensure epithelial cells respond to microbes appropriately and that potentially hazardous commensals remain distanced from the soma proper. Breakdown of these propitiating mechanisms elicits unchecked inflammation and can lead to pathology …

The Role Of Intestinal Epithelial Cells And The Regulation Of The Polymeric Immunoglobulin Receptor In Homeostasis And Inflammation, Aubrey Leigh Frantz

Theses and Dissertations--Microbiology, Immunology, and Molecular Genetics

The mammalian intestine harbors an estimated 100 trillion microorganisms, which normally maintain a mutually beneficial relationship with the host. The intestinal epithelium consists of a single layer of intestinal epithelial cells (IECs) that provides a physical barrier as well as innate immune defense, preventing this vast community of microbes from entering host tissues. Secretory immunoglobulin A (SIgA) acts as the first line of antigen-specific immunity at the interface between the gut microbiota and the intestinal epithelium. Polymeric IgA secreted by plasma cells in the intestinal lamina propria is transported across IECs by the polymeric immunoglobulin receptor (pIgR). Defects in epithelial …

Prion Characterization Using Cell Based Approaches, Vadim Khaychuk

Theses and Dissertations--Microbiology, Immunology, and Molecular Genetics

Prions are the causative agents of a group of lethal, neurodegenerative conditions that include sheep scrapie, bovine spongiform encephalopathy (BSE), and human Creutzfeldt-Jakob disease (CJD). Prions are derived from the conversion of a normal, primarily alpha-helical, cellular prion protein (PrP^C), to an infectious, beta sheet-rich conformer (PrP^Sc). Many unresolved issues surround the process of PrP conversion, and we know very little about cellular responses to these unique pathogens. Our lack of knowledge relates, in part, to the difficulty of infecting cells in vitro with prions. While expression of PrP^C is an absolute requirement for prion …

A Diet Enriched In Stearic Acid Protects Against The Progression Of Type 2 Diabetes In Leptin Receptor Deficient Mice (Db/Db), Valerie Lynn Reeves

Theses and Dissertations--Physiology

Dietary saturated fat intake contributes to diabetes and cardiovascular disease, as shown in numerous animal and human studies. However, the hypothesis that stearic acid, a saturated fat, has beneficial effects on these conditions has not been adequately tested. Leptin receptor deficient mice (db/db) and wild-type mice were fed either chow or a high fat diet enriched in either stearic acid or oleic acid for ten weeks. The progression of diabetes was evaluated with blood glucose, insulin, and metabolic parameter measurements. At the conclusion of the study, pancreatic islet organization was examined, and blood, liver and feces were assayed for fatty …

C-Abl And Arg Drive Cancer Chemoresistance Via Activation Of Multiple Signaling Pathways, Jonathan Thomas Sims

Theses and Dissertations--Pharmacology and Nutritional Sciences

Despite 35 years of clinical trials, there has been little improvement in one-year survival rates with any chemotherapeutic regimen for the treatment of metastatic melanoma due to resistance to all known agents. Regardless of advances in detection and prevention, diagnosis of metastatic disease remains a death sentence. Resistance mechanisms, including aberrant kinase signaling and drug transport pumps, indicate a need for identification of other therapeutic targets that impinge upon multiple signaling pathways. The Abl family of non-receptor tyrosine kinases (c-Abl, Arg) has been indicted as a causative force in leukemia for more than three decades; however, their role in solid …

Inflammatory Interactions And Secretion In Cardiac Remodeling, Fanmuyi Yang

Theses and Dissertations--Physiology

Heart failure contributes to nearly 60,000 deaths per year in the USA and is often caused by hypertension and preceded by the development of left ventricular hypertrophy (LVH). LVH is usually accompanied by intensive interstitial and perivascular fibrosis which may contribute to arrhythmogenic sudden cardiac death. Emerging evidence indicates that LV dysfunction in patients and animal models of cardiac hypertrophy is closely associated with perivascular inflammation.

To investigate the role of perivascular inflammation in coronary artery remodeling and cardiac fibrosis during hypertrophic ventricular remodeling, we used a well-established mouse model of pressure-overload-induced LVH: transverse aortic constriction (TAC). Early perivascular inflammation …

Fiscal Federalism And Spatial Interactions Among Governments, Longjin Chen

Theses and Dissertations--Economics

This dissertation examines multiple state and local expenditure categories in the United States to expand understanding of fiscal federalism and spatial interactions among governments. First, the author investigates the relationship between police expenditures and crime rates from a spatial perspective. Both police expenditures and crime rates in one state are found to exhibit a similar pattern to that in neighboring states. Spatial correlation is also detected between police expenditures and crime rates. As police of neighbors in fact deter crime at home, there are positive externalities present among the states. Second, the author conducts new tests on the Leviathan hypothesis, …

Essays On The Persistence Of Poverty, T M Tonmoy Islam

Theses and Dissertations--Economics

My dissertation investigates the reasons behind the persistence of income among individuals and US counties. I look at the role of initial conditions in explaining current level of income. In my first essay, I look at how childhood neighborhood conditions affect income of a person. To study persistence, I model income as an autoregressive process where the coefficient on the lagged dependent variable heterogeneous across individuals. In my second essay, I derive a new way to measure chronic poverty, or long term poverty. Current measures of chronic poverty cannot be used to compare improvements of poverty rates over time. Using …

Three Essays On The Health Insurance Coverage Of Young Adults, David M. Yaskewich

Theses and Dissertations--Economics

This dissertation examines the health insurance status of young adults during the transition to adulthood. In a series of three essays, I analyze what happens as young adults reach important milestones and the effects of public policies. The first essay is a descriptive study on how insurance status changes after reaching age 19 and graduating from college. The likelihood of becoming uninsured rises sharply once turning age 19 and then peaks at age 23. While the proportion uninsured also increases following college graduation, this increase disappears after one year. The second essay analyzes the effect of a dependent age law …

The Risk Of Violence And Intimate Partner Choice Within A Risk Society, Adam J. Pritchard

Theses and Dissertations--Sociology

This dissertation examines the influence of competing risks in shaping individuals' choices about potential intimate relationships. According to Ulrich Beck's "risk society" theory, the individualization of social risks has direct and measurable consequences for the ways people organize and evaluate potential intimate relationships (Beck & Beck-Gernsheim, 1995, 2002, 2004; Giddens, 1994; Lupton, 2006). This study investigates the ways in which subjective or identity-related risks hypothesized by scholars of late modernity shape the perception and the actual risk of dating violence. Empirical research on dating violence identifies many objective “risk factors” related to a person’s chances of experiencing intimate partner violence; …

Evaluating Retention In Medical Care And Its Impact On The Health Outcomes Of Individuals Living With Human Inmmunodeficiency Virus, Timothy N. Crawford

Theses and Dissertations--Epidemiology and Biostatistics

In the last few years, engagement in medical care among individuals living with HIV has become a major priority among HIV medical providers and public health researchers. Engagement in medical care is an important concept as it involves the process of linking newly diagnosed individuals into medical care and retaining those individuals in care throughout the course of their infection. Although there have been major advances in the management of HIV, like the advent of Highly Active Antiretroviral Therapy, morbidity and mortality due to HIV cannot be fully reduced if the individual does not optimally retain in care. Retention in …

The Relationship Of Social Stress, Economic Hardship, And Psychological Distress To Addiction Severity Among Kentucky Substance Abuse Treatment Participants, Elizabeth A. Wahler

Theses and Dissertations--Social Work

Stress is associated with poor mental health, specifically anxiety and depression, and stress and mental health problems are predictors of substance dependence and relapse. Social characteristics, such as racial/ethnic minority status, female gender, and low socioeconomic status, are often associated with increased psychological distress and substance use disorders. Pearlin’s social stress theory postulates that this association is due to increased exposure to stress and subsequent experiences of distress related to social disadvantage and decreased access to resources for coping with stress. This project uses a social stress theoretical perspective to examine predictors of substance use after treatment entry and follow-up …

Human Capital, Mental Health, Substance Use And Social Support Among Low-Income Women, Sarabeth Leukefeld

Theses and Dissertations--Social Work

Low-income women, including women who receive welfare, are some of the most misunderstood citizens in the U.S. Low-income women often live in extreme situations that are complicated by poverty and multiple issues related to human capital, social support, mental health, and substance use. These factors make low-income women unique in that they contribute not only to the women’s current situations, but to their potential for future self-sufficiency. The majority of previous studies have described these factors as barriers to self-sufficiency. This study explored these factors differently by examining the extent to which human capital is associated with mental health problems …