Digital Commons Network^™

A Markov Transition Model To Dementia With Death As A Competing Event, Liou Xu

University of Kentucky Doctoral Dissertations

The research on multi-state Markov transition model is motivated by the nature of the longitudinal data from the Nun Study (Snowdon, 1997), and similar information on the BRAiNS cohort (Salazar, 2004). Our goal is to develop a flexible methodology for handling the categorical longitudinal responses and competing risks time-to-event that characterizes the features of the data for research on dementia. To do so, we treat the survival from death as a continuous variable rather than defining death as a competing absorbing state to dementia. We assume that within each subject the survival component and the Markov process are linked by …

15N Solid-State Nmr Detection Of Flavin Perturbation By H-Bonding In Models And Enzyme Active Sites, Dongtao Cui

University of Kentucky Doctoral Dissertations

Massey and Hemmerich proposed that the different reactivities displayed by different flavoenzymes could be achieved as a result of dominance of different flavin ring resonance structures in different binding sites. Thus, the FMN cofactor would engage in different reactions when it had different electronic structures. To test this proposal and understand how different protein sites could produce different flavin electronic structures, we are developing solid-state NMR as a means of characterizing the electronic state of the flavin ring, via the ¹⁵N chemical shift tensors of the ring N atoms. These provide information on the frontier orbitals. We propose that …

Synthesis, Characterization And Development Of Catalysts For Co2 Capture, Anitha Suhas Wishrojwar

University of Kentucky Master's Theses

Fossil fuel and advanced industrialization techniques contribute to global warming through emissions of greenhouse gases such as CO₂. In order to mitigate climate change, there is a desperate need to reduce CO₂ emissions from different sources. CO₂ capture and sequestration (CCS) play an important role in these reductions.

Naturally occurring enzymes, e.g., carbonic anhydrase (CA), can catalyze these reactions in living systems. Much effort has been focused on complexes of zinc with ligands such as teta, cyclen and tripodal ligands including BIMA and Trispyrazolylborates. These complexes have many interesting CO₂ capture properties, but maintain toxic …

Cover Crops And Tillage Systems For Organic Corn Production In Kentucky, Alfonso Suarez

University of Kentucky Master's Theses

Organic corn (Zea mays L.) producers generally use intensive tillage for weed control. No-till methods reduce soil erosion, conserve water, maintain soil structure and reduce CO₂ emissions. The objective of this study was test different cover crops, tillage systems, N sources and N rates for organic corn production. Two tillage systems (no-till and moldboard plow), two cover crops [hairy vetch (Vicia villosa) and rye (Secale cereale)] and two organic N sources [Louisville Green (LG) and Nature Safe (NF)] at four N rates (45, 90, 135, 180 kg N ha^-1) were evaluated …

Representación De La Violencia En La Novela Del Narcotráfico Y El Cine Colombiano Contemporáneo, Claudia Ospina

University of Kentucky Doctoral Dissertations

This dissertation analyzes the representation of violence in Colombian novels and films from the last two decades of the XX century. Aided by current theories of violence and representation on the one hand, and an interdisciplinary methodology that analyses the phenomenon of the violence of drug trafficking from different perspectives on the other, my analysis examines the challenges and limits of literary and cinematic representation as it grapples with the extreme realities of life in Colombia’s major cities. The central body of my thesis focuses on three novels and two films, selected for the marked differences that inform their generic …

Effects Of Livestock Antibiotics On Nitrification, Denitrification, And Microbial Community Compositon In Soils Along A Topographic Gradient, Sagarika Banerjee

University of Kentucky Master's Theses

Several types of antibiotics (roxarsone, virginiamycin, and bacitracin) are widely included in poultry feed to improve animal growth yields. Most of the antibiotics are excreted in manure which is subsequently applied to soils. One concern with this practice is that antibiotics may affect several microbially-mediated nutrient cycling reactions in soils that influence crop productivity and water quality. The main objectives of this study were to determine the effects of livestock antibiotics on nitrification, denitrification, and microbial community composition in soils along a topographic gradient. These objectives were addressed in a series of lab experiments by monitoring changes in inorganic N …

A Qualitative Study Of The Perceived Health Benefits Of A Therapeutic Riding Program For Children With Autism Spectrum Disorders, Margaret Ann Stickney

University of Kentucky Doctoral Dissertations

Therapeutic horseback riding can be recommended as a useful health promotion intervention for individuals with disabilities who face challenges to optimal health and wellness. This qualitative study examined the perceived benefits of a therapeutic riding program for children with autism spectrum disorders (ASD), with particular focus on aspects that can potentially help maximize the physical, emotional, and social health of this population.

This study utilized multiple methods to gain an in-depth perspective on the benefits of a therapeutic riding program based at Central Kentucky Riding for Hope in Lexington, Kentucky, for subjects presenting primarily with ASD. Focus groups were held …

Lactone-Carboxylate Interconversion As A Determinant Of The Clearance And Oral Bioavailabilty Of The Lipophilic Camptothecin Analog Ar-67, Eyob Debebe Adane

University of Kentucky Doctoral Dissertations

The third generation camptothecin analog, AR-67, is undergoing early phase clinical trials as a chemotherapeutic agent. Like all camptothecins it undergoes pH dependent reversible hydrolysis between the lipophilic lactone and the hydrophilic carboxylate. The physicochemical differences between the lactone and carboxylate could potentially give rise to differences in transport across and/or entry into cells. In vitro studies indicated reduced intracellular accumulation and/or apical to basolateral transport of AR-67 lactone in P-gp and/or BCRP overexpressing MDCKII cells and increased cellular uptake of carboxylate in OATP1B1 and OATP1B3 overexpressing HeLa-pIRESneo cells. Pharmacokinetic studies were conducted in rats to study the disposition and …

Cardiac Rhythm During Mechanical Ventilation And Weaning From Ventilation, Muna Hassan Hammash

University of Kentucky Doctoral Dissertations

The transition from mechanical ventilation (MV) to spontaneous ventilation during weaning is associated with hemodynamic alterations and autonomic nervous system (ANS) alterations (reflected by heart rate variability [HRV]). Although cardiac dysrhythmias are an important manifestation of hemodynamic alterations, development of dysrhythmias during MV and weaning and subsequent impact on length of MV has received little attention.

The purposes of this dissertation were to 1) evaluate the relationship of heart rate variability (HRV) during weaning to the development of cardiac dysrhythmias and 2) determine the relationship of cardiac dysrhythmias to length of MV.

A convenience sample of 35 patients (66.7% men; …

Role Of Group X Secretory Phospholipase A2 In Murine Adipocytes, Xia Li

University of Kentucky Doctoral Dissertations

The secretory phospholipase A₂ (sPLA₂) family is a group of enzymes that catalyze the hydrolysis of glycerophospholipids at the sn-2 position, generating free fatty acids and lysophospholipids. The sPLA₂ family has been implicated in various physiological and pathological activities. Eleven sPLA₂’s have been identified in mammals, and the function of each isoform likely reflects its tissue distribution and substrate specificity. Studies in vitro indicate that Group X (GX) sPLA₂ potently releases arachidonic acid (AA) and lysophosphatidylcholine from mammalian cell membranes. Interestingly, some of the biological effects mediated by GX sPLA₂ in vitro …

Theoretical Modeling And Analysis Of Ammonia Gas Sensing Properties Of Vertically Aligned Multiwalled Carbon Nanotube Resistive Sensors And Enhancing Their Sensitivity, Shripriya Darshini Poduri

University of Kentucky Master's Theses

Vertically aligned Multiwalled Carbon Nanotubes (MWCNTs) were grown in the pores of Anodized Aluminum Oxide (AAO) templates and investigated for resistive sensor applications. High Sensitivity of 23% to low concentration (100 ppm) of ammonia was observed. An equivalent circuit model was developed to understand the current flow path in the resistive sensor. This helped us in achieving high sensitivities through amorphous carbon (a-C) layer thickness tailoring by employing post-growth processing techniques like plasma etching.

A simulation model in MATLAB was developed to calculate the device resistance and the change in the sensitivity as a function of device parameters. The steady …

The Role Of Abcg2 In Drug Active Transport In Milk, Lipeng Wang

University of Kentucky Doctoral Dissertations

Drug active transport into milk is a major concern for breastfeeding mothers and healthcare providers. Studies from the literature indicated that breast cancer resistance protein (ABCG2) plays an important role in drug transfer into milk. There has been limited study on stereoselective interactions with ABCG2. A mechanistic analysis of flux across cell monolayer model is a critical first step toward extrapolating in vitro results for predicting in vivo disposition (including distribution into milk), drug disposition or drug-drug interactions.

The objectives of this thesis were (1) to establish a “Chemical knockout model” in rat for studying drug accumulation into milk, (2) …

What Nurses Say: Communication Behaviors Associated With The Competent Nursing Handoff, Anne Claiborne Ray Streeter

University of Kentucky Doctoral Dissertations

Communication competence and medical communication competence served as the theoretical framework for this research that seeks to identify specific communication behaviors associated with what nurses say constitute a communicatively competent patient handoff at the nursing change of shift. Data collected from 286 nurses responding to an online modified Medical Communication Competence Scale posted at www.allnurses.com supported the hypotheses that information exchange (information giving, seeking and verifying) and socioemotional communication behaviors are rated more highly in the best patient handoffs than in the worst ones. Research questions found that the incoming nursing role rated behaviors associated with information verifying and socioemotional …

Health System Processes, Clinician Attitudes, And Referrals To Tobacco Treatment Programs, Karma Bryan Cassidy

University of Kentucky Doctoral Dissertations

Assisting smokers to quit and stay quit is the most important intervention clinicians can undertake to improve the length and quality of life of patients who use tobacco. The chronic, relapsing nature of tobacco dependence complicates tobacco treatment. Tobacco treatment counseling programs provide on-going support to help patients avoid relapse. Assistance with a referral increases the likelihood that patients will participate in counseling, but few clinicians regularly assist with referrals to tobacco treatment programs. This dissertation examined health system processes and clinician attitudes that influence the likelihood that clinicians will refer their patients for tobacco treatment counseling.

Three papers examined …

Impact Of A 16-Week Behavioral Weight-Loss Program On Dietary And Physical Activity Changes, Eunkyung Lee

University of Kentucky Master's Theses

Behavioral weight loss programs have been shown to be effective for short-term weight loss, however the impact of these programs on dietary changes is unclear. This study examined the changes in participant’s diet and physical activity over the course of a 16-week Internet behavioral weight-loss program. A single-center randomized controlled trial was conducted from August 2008 to December 2008 in Lexington, KY, and sixty-six women whose mean (SD) age was 48.6 (10.8) years and body mass index was 31.8 (3.7) kg/m² completed all dietary and physical measures. Participants received two face-to-face group sessions with a dietitian, at baseline and …

Constructing Inequality In Three Kentucky Communities: Discourses Of Blame And Responsibilty, Elizabeth J. New

University of Kentucky Master's Theses

This thesis focuses on the social determinants of health in Appalachia. Using anthropological ethnographic field methods, this thesis explores the ways in which public assistance programs and exchanges between health care practitioners and clients result in discourses of blame and responsibly. Also included is a discussion of the role that health insurance plays in granting or denying individuals living in poverty the opportunity for treatment and care. The narratives collected for this project then become the bases for a critical examination of the public discourse surrounding health care reform in the United States in 2009 and 2010.

Structural Instability Of Human Ribosomal Rna Gene Clusters, Dawn Michelle Stults

University of Kentucky Doctoral Dissertations

The human ribosomal RNA genes are critically important for cell metabolism and viability. They code for the catalytic RNAs which, encased in a housing of more than 80 ribosomal proteins, link together amino acids by peptide bonds to generate all cellular proteins. Because the RNAs are not repeatedly translated, as is the case with messenger RNAs, multiple copies are required. The genes which code for the human ribosomal RNAs (rRNAs) are arranged as clusters of tandemly repeated sequences. Three of four catalytic RNAs are spliced from a single transcript. The genes are located on the short arms of the five …

Somatic Injury Precedes Distal Atrophy Following Excitotoxic Hippocampal Insult, Lynda Sharrett-Field

University of Kentucky Master's Theses

Excitotoxicity can lead to increases in intracellular Na⁺ and Ca²⁺ concentrations via the glutamatergic NMDA receptors, which can lead to cell death. Detailing the time-dependent degradation of neuronal components in response to excitotoxic challenge may help elucidate the sequence in which these signaling pathways are initiated and further, associate these pathways with topographic cellular demise. Using organotypic hippocampal slice culture technique, tissue from neonatal rat pups was exposed to NMDA, APV, or co-exposed for 24, 72 or 120 hours. Fluorescent microscopy of propidium iodide (PI) was used to evaluate neuronal membrane damage, changes in the density of mature …

Health Literacy: A Bibliometric And Citation Analysis, Robert M. Shapiro Ii

University of Kentucky Master's Theses

The concept of health literacy finds its origins in the field of education. In its brief history the definition, structure, and direction of the field has changed dramatically and has emerged as a multidisciplinary endeavor full of discipline specific manifestations, most recently, public health literacy. Using bibliometric and citation analyses, this study investigated the field of health literacy from the first use of the term in 1974 to the present year, 2010. A range of databases from the various fields that have contributed to the field were searched using the keyword string, “health literacy.” Data was organized, cleaned and parsed …

Explorations In Homeoviscous Adaptation And Mass Spectral Analysis Of Membrane Lipids, Michael Douglas Timmons

University of Kentucky Doctoral Dissertations

The focus of this dissertation is centered on the mass spectral analysis of lipids and changes occurring in keeping with the concept of homeoviscous adaptation [1]. Homeoviscous adaptation is the process of modification of membrane lipids in response to environmental stimuli [1]. Dissertation investigations applied this concept to prokaryotic and eukaryotic organisms, and expanded the perception of environmental factors from exogenous organic solvents to intracellular environment.

The field of lipidomics deals with the analysis of phospholipid and fatty acid components of membranes the changes that occur due to environmental stimuli and their biological significance [2-6]. The high sensitivity of mass …

Why Do They Go? Community College Students And Post-Secondary Pursuits In Central Appalachia, Christina Jo Wright

University of Kentucky Doctoral Dissertations

This dissertation focuses on how rural community college students make decisions regarding their post-secondary plans. To understand these decision processes, I interviewed students, faculty and administrators at Southeast Community and Technical College in Harlan County, Kentucky. The literature informing my research reflects on rural college going patterns. Most studies connect place and post-secondary plans. Central Appalachia has among the lowest population percentages with Bachelor degrees in the country. Studies argue this is because of limited application for such degrees in the region. Matching their education and training to local job market requirements, people hesitate to complete advanced degrees when little …

Studies Toward The Total Synthesis Of (±)-Α-Yohimbine By Double Annulation, Raghu Ram Chamala

University of Kentucky Doctoral Dissertations

The indole alkaloids, a class of natural products, have received much synthetic attention for years due to their diverse structures and interesting biological properties. We are particularly interested in synthesizing some of the yohimbine alkaloids extracted from the bark of a tall evergreen African tree (Corynanthe yohimbe, commonly known as fringe tree). Yohimbine and its stereoisomers have been tempting targets for synthetic organic chemists for more than fifty years. These compounds feature a pentacyclic ring system with two heteroatoms and five stereogenic centers.

Broadly, the fifteen different synthetic approaches that led to the successful completion of yohimbine alkaloids …

Chromium, Copper, And Arsenic Concentration And Speciation In Soil Adjacent To Chromated Copper Arsenate (Cca) Treated Lumber Along A Topohydrosequence, Donald Roy Schwer Iii

University of Kentucky Master's Theses

Arsenic (As), Chromium (Cr), and Copper (Cu) are ubiquitous in soils as a result of anthropogenic and geogenic processes. The fate of As, Cr, and Cu in the environment is largely governed by their speciation, which is influenced by soil physiochemical properties. This study investigated the influence of soil physiochemical properties and landscape position on As, Cr, and Cu concentration and speciation in soils adjacent to Chromated Copper Arsenate (CCA) treated lumber fence posts. Concentration gradients showed elevated total As and Cu adjacent to the three fence posts, which decreased with increasing distance from the posts. In addition, As and …

Remote Controlled Hydrogel Nanocomposites: Synthesis, Characterization, And Applications, Nitin S. Satarkar

University of Kentucky Doctoral Dissertations

There is significant interest in the development of hydrogels and hydrogel nanocomposites for a variety of biomedical applications including drug delivery, sensors and actuators, and hyperthermia cancer treatment. The incorporation of nanoparticulates into a hydrogel matrix can result in unique material characteristics such as enhanced mechanical properties, swelling response, and capability of remote controlled (RC) actuation. In this dissertation, the development of hydrogel nanocomposites containing magnetic nanoparticles/carbon nanotubes, actuation with remote stimulus, and some of their applications are highlighted.

The primary hydrogel nanocomposite systems were synthesized by incorporation of magnetic nanoparticles into temperature responsive N-isopropylacrylamide (NIPAAm) matrices. Various nanocomposite properties …

Public School Choice And The Public-Private School Decision, Kylie Goggins

University of Kentucky Doctoral Dissertations

This dissertation is a compilation of three studies related to public school choice issues. Chapter 2 examines whether access to public schools of choice influences a household’s decision to choose private school for their child. I employ a multistate, individual-level data-set on students and their families — for which I have been granted access to restricted geo-code information. I supplement these data by matching students with their respective school districts using geographic information systems (GIS); I then examine whether relative measures of public school choice (PSC) in a school district influence the household’s public-private school decision. I find slight evidence …

Evolutionary Perspective Of Nicotine To Nornicotine Conversion, Its Regulation And Characterization Of Ein2 Mediated Ethylene Signaling In Tobacco, Manohar Chakrabarti

University of Kentucky Doctoral Dissertations

Nicotine, nornicotine, anabasine and anatabine are four major alkaloids in tobacco, of which nicotine is predominant. In many tobacco cultivars and also in other Nicotiana species, nicotine is converted to nornicotine, which in turn gives rise to potent carcinogen NNN. Nicotine to nornicotine conversion via nicotine-N-demethylation is mediated by the CYP82E family of P450 enzymes. Tobacco (Nicotiana tabacum) converts in senescing leaves, while its diploid progenitors N.tomentosiformis and N.sylvestris convert in both green and senescing and only in senescing leaves, respectively. Previously it has been shown that N.tomentosiformis has different active conversion loci in green and senescing leaves. …

Three Worlds Of Western Punishment: A Regime Theory Of Cross-National Incarceration Rate Variation, 1960-2002, Matthew Demichele

University of Kentucky Doctoral Dissertations

This dissertation offers an explanation of cross national incarceration rate variation for 17 industrialized countries for the second half of the 20^th century. Both historical case studies and time-series cross-section analyses are used to provide an institutional explanation of incarceration rate differences. Borrowing from Weber’s Sociology of Law and comparative legal scholarship, it is suggested that three types of legal thinking exist among western democracies—Common, Romano-Germanic, and Nordic law. A regime approach commonly applied in political economic explanations of welfare state development is used to quantify the legal and criminal justice institutional differences between 1960 and 2002 to assert …

Alcohol Dose And Aggression: Another Reason Why Drinking More Is A Bad Idea, Aaron Adriel Duke

University of Kentucky Master's Theses

A wealth of studies have examined the impact of alcohol on violence; however, only a small number have addressed differences elicited by different doses of alcohol. Such studies are seriously limited by mixed findings, small sample sizes, inconsistent alcohol doses and control conditions, a bias toward studying only male participants, and the predominant use of only one particular measure to assess aggression. The present laboratory investigation was designed to elucidate and advance this literature by improving upon these limitations. Participants were 187 (95 men and 92 women) social drinkers. Following the consumption of one of 6 alcohol doses (i.e., 0.0g/kg; …

Local Synaptic Network Interactions In The Dentate Gyrus Of A Cortical Contusion Model Of Posttraumatic Epilepsy, Robert F. Hunt Iii

University of Kentucky Doctoral Dissertations

Posttraumatic epilepsy is a common consequence of brain trauma. However, little is known about how long-term changes in local excitatory and inhibitory synaptic networks contribute to epilepsy after closed-head brain injury. This study adapted a widely used model of experimental brain injury as a mouse model of posttraumatic epilepsy. Behavioral seizure activity and alterations in synaptic circuitry in the dentate gyrus were examined in mice after experimental cortical contusion brain injury. Spontaneous behavioral seizures were observed in 20% of mice after moderate injury and 36-40% of mice weeks after severe injury. In the dentate gyrus, most mice displayed regionally localized …

A Comparison Of The Reiss Profile With The Neo Pi-R Assessment Of Personality, Sara E. Boyd

University of Kentucky Master's Theses

The purpose of this thesis was to determine whether the NEO Personality Inventory-Revised (NEO PI-R) could account for significant variance within a measure of personality developed for the intellectually disabled (i.e., the Reiss Profile of Fundamental Motives), as well as to consider their comparative validity. The NEO PI-R and the Reiss Profile of Fundamental Motives were administered to 127 undergraduate students in conjunction with the Personality Research Form (PRF) and the Behavior Report Form (BRF). The NEO PI-R was able to account for a substantial amount of variance in the Reiss Profile scales, and the Reiss and the NEO accounted …