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Evaluation Of Natural Antimicrobial Phenolic Compounds Against Foodborne Pathogens, Hayriye Cetin-Karaca

University of Kentucky Master's Theses

Raw and processed foods are vulnerable to contamination during their production, distribution and sale. Thus, a wide variety of chemical preservatives are used in the food industry to prevent the growth of food spoilage and pathogenic bacteria. However, health and economic concerns have led to an intensive search for natural alternatives, such as plant extracts, that can safely be used as substitutes for synthetic antimicrobials and preservatives to partially or completely inhibit the growth of bacteria.

This study evaluated the antimicrobial effects of natural phenolic compounds extracted from vegetables, fruits, herbs and spices. The main objective was to determine the …

Isolation And Elucidation Of The Chrysomycin Biosynthetic Gene Cluster And Altering The Glycosylation Patterns Of Tetracenomycins And Mithramycin-Pathway Molecules, Stephen Eric Nybo

University of Kentucky Doctoral Dissertations

Natural products occupy a central role as the majority of currently used antibiotic and anticancer agents. Among these are type-II polyketide synthase (PKS)-derived molecules, or polyketides, which are produced by many representatives of the genus Streptomyces. Some type-II polyketides, such as the tetracyclines and the anthracycline doxorubicin, are currently employed as therapeutics. However, several polyketide molecules exhibit promising biological activity, but due to toxic side effects or solubility concerns, remain undeveloped as drugs.

Gilvocarcin V (GV) (topoisomerase II inhibitor) has a novel mechanism of action: [2+2] cycloaddition to thymine residues by the 8-vinyl side chain and cross-linking of histone …

Modeling And Quantitative Analysis Of White Matter Fiber Tracts In Diffusion Tensor Imaging, Xuwei Liang

University of Kentucky Doctoral Dissertations

Diffusion tensor imaging (DTI) is a structural magnetic resonance imaging (MRI) technique to record incoherent motion of water molecules and has been used to detect micro structural white matter alterations in clinical studies to explore certain brain disorders. A variety of DTI based techniques for detecting brain disorders and facilitating clinical group analysis have been developed in the past few years. However, there are two crucial issues that have great impacts on the performance of those algorithms. One is that brain neural pathways appear in complicated 3D structures which are inappropriate and inaccurate to be approximated by simple 2D structures, …

Genotoxin-Induced Acetylation Of The Werner Syndrome Protein (Wrn) And Effect On Its Dna Metabolic Function, Enerlyn Meliza Lozada Santiago

University of Kentucky Doctoral Dissertations

Loss of function of the WRN protein causes the genetic disorder Werner Syndrome that is characterized by increased cancer and premature aging. WRN belongs to the RecQ helicase family that plays key roles in preventing genome instability. In response to treatment with genotoxins, WRN is subject to post-translational modification. The relationship of post-translational modification of WRN with its function in DNA metabolism is unknown. There is accumulating evidence suggesting that WRN contributes to the maintenance of genomic integrity through its involvement in DNA replication. Consistent with this notion, WS cells are sensitive to DNA replication inhibitors and DNA damaging agents …

The Absence Of Abcd2 Reveals A Novel Role For Peroxisomes In The Protection From Metabolic Syndrome, Jingjing Liu

University of Kentucky Doctoral Dissertations

ABCD2 (D2) is a peroxisomal ATP binding cassette (ABC) transporter that is expressed in brain, adrenal and liver. D2 is transcriptionally regulated by key transcriptional factors that control lipid and glucose metabolism. Therefore, we examined its role in adipose tissue. These studies revealed that D2 is highly abundant in adipose tissue and upregulated during adipogenesis. However, D2 deficiency does not affect either adipogenesis or lipid accumulation. An examination of the lipid profile of adipose tissue revealed the accumulation of C20 and C22 fatty acids in D2 deficient (D2‐/‐) mice. When challenged with a diet enriched in erucic acid (C22:1, 10% …

Ethnic Identity And Perceived Discrimination As Predictors Of Academic Attitudes: The Mediating And Moderating Roles Of Psychological Distress And Self-Regulation, Hui Chu

University of Kentucky Master's Theses

The current study addressed the deficiency in research by examining risk factors for immigrant children that may lead to academic disengagement (such as ethnic discrimination by peers and teachers, and psychological distress) and resilience factors that promote academic engagement (such as the development of a positive ethnic identity). Children who had stronger, more positive ethnic identities had more positive academic attitudes. Furthermore, the more the children were teased by their peers and graded unfairly by their teachers because of their ethnicity, the more they thought school was less important, less useful and felt less efficacious about school and valued school …

Conceptualizing And Improving Red Wine Grape Cultivars Grown In Kentucky, Matthew Simson

University of Kentucky Master's Theses

Wine sensory attributes are associated with quality of wines. Cabernet Franc did not possess good coloration of its wine. Therefore, in the 2009 and 2010 growing seasons, studies including the sampling of four red wine grape cultivars from the end of flowering throughout the rest of the season and applying treatments to Cabernet Franc grapevines at veraison were commenced to address suitability and color enhancement, respectively. The study examining Cabernet Franc, Cabernet Sauvignon, Chambourcin, and Norton looked at sampling their grapes at two-week intervals from times post-flowering to understand the demands of each cultivar during key stages of berry development, …

The Effect Of A Physical Education Games Unit On Children’S Participation In Neighborhood Physical Activity, Beth Erin Eddy

University of Kentucky Master's Theses

Many strategies to increase children’s physical activity have been studied, noted and implemented. It is important that physical educators realize their role in increasing physical activity both in school and outside of school. In order to promote physical activity outside of school it is important to understand what types of physical activities in which children enjoy participating. This study manipulated specific games taught in physical education classes and then explored how many and what types of these activities were continued in out-of-school free play at home in the children’s neighborhood. The students’ activities increased after the intervention, especially the activities …

Examining Gender Differences In Persistence In Higher Education Among African American Students, Yvonne Townsend

University of Kentucky Master's Theses

This Study examined issues related to persistence in higher education among African American students, using the prominent model proposed by Vincent Tinto. The intentions were to examine the growing gender gap among African American students. The study examines factors from the Tinto model such as high school GPA, College GPA, college social integration and academic integration to try and explain the effects of gender among African American students. This research also attempts to elaborate the Tinto model by considering high school extracurricular activities as a pre-entry attribute that has an effect on persistence in higher education. Use of the Tinto …

World Production And Trade Of Pistachios: The Role Of The U.S. And Factors Affecting The Export Demand Of U.S. Pistachios, Zijuan Zheng

University of Kentucky Master's Theses

The primary purpose of this study is to evaluate the role of the US in the worldwide production and trade of pistachios, identify and estimate the major factors affecting export demand for US pistachios in 21 major markets, accounting for 78 percent of total US pistachio exports. The study estimated the impacts of US pistachio own price, cross price, importing markets’ GDP, real exchange rates and effect of food safety shocks. A panel data analysis was conducted using data from 1989 to 2009. A Houseman test indicated that the random effects estimator was the chosen estimator. Elasticity analysis indicated that …

The Relationship Of Anxiety, Coping, Thinking Style, Life Satisfaction, Social Support, And Selected Demographics Among Young Adult College Students, Jihan Saber Raja Mahmoud

University of Kentucky Doctoral Dissertations

Anxiety is prevalent among 13 % of young adult college students and is associated with emotional and behavioral consequences that adversely affect their mental and physical well-being. The major challenge for implementing evidence-based interventions is the lack of a multidimensional approach for evaluating anxiety in this population.

The purpose of this dissertation was to develop an evidence-based theoretical framework for studying the phenomenon of anxiety in young adult college students. Three studies were conducted to achieve this purpose. First, the psychometric properties of the 21-item shortened version of the Depression Anxiety and Stress Scale (DASS-21) were evaluated in a sample …

The Response Of Tall Fescue And Its Fungal Endophyte To Climate Change, Glade Blythe Brosi

University of Kentucky Master's Theses

Tall fescue is the most common cool-season grass in the eastern USA, with broad economic and ecological importance to the region. Tall fescue is known to associate with a fungal endophyte, Neotyphodium coenophialum, whose presence can decrease biotic and abiotic stress experienced by the plant. This thesis evaluates the response of tall fescue and the fungal endophyte symbiosis to predicted climate change. I participated in two multi-factor climate change projects where I investigated the response of tall fescue tissue chemistry and growth to various climate change factors. Endophyte-infected (E+) tall fescue had decreased alkaloid production under elevated CO_{2 …}

Analyzing Educational Attainments And Occupational Outcomes Of Tibetan Refugees Living In India, Tenzin Palkyi

University of Kentucky Master's Theses

Opportunities of mass education are a relatively new phenomenon in the Tibetan community. Following the incidents of 1959, the Dalai Lama and thousands of Tibetans fled into India. Mass education was implemented and sustained within the Tibetan community for the first time. The goal of this exploratory research is to study the impact of mass education on the first generations of Tibetans who experienced it in exile. This study analyzes the gendered pattern in subjects students choose to pursue, their educational attainment and the kinds of jobs they assume after graduation. The study presents a quantitative analysis of data spanning …

Analysis Of Student & Teacher Outcomes From Pre-Existing Data Obtained Through The Low Incidence Initiative: Teaching Academic Age-Appropriate Learning Via Communication Project, April M. Holman

University of Kentucky Master's Theses

Students with significant cognitive disabilities frequently exhibit reduced communicative and academic competence. The Low Incidence Initiative (LII) project was a professional development model designed to train school-based teams to facilitate increased communicative and academic competence with such students via distance-technology coaching. This study analyzed pre-existing data from year one of the LII. Data were analyzed to determine effectiveness of the project on communication status of students and on training school personnel to accurately identify student levels of communication, and for overall satisfaction with the project. Results indicated that all student participants demonstrated improvement in expressive communication output. 100% of students …

The Role Of The Nr4a Orphan Nuclear Receptor Nor1 In Vascular Cells And Atherosclerosis, Yue Zhao

University of Kentucky Doctoral Dissertations

The neuron-derived orphan receptor 1 (NOR1) belongs to the NR4A nuclear receptor subfamily. As an immediate early response gene, NOR1 is rapidly induced by a broad spectrum of physiological and pathological signals. Functional studies demonstrate NOR1 as a constitutively active ligand-independent nuclear receptor whose transcriptional activity is dependent on both expression level and posttranslational modifications. To date, an increasing number of studies have demonstrated a pivotal role of NOR1 in the transcriptional control of metabolism and the development of cardiovascular diseases.

In this dissertation, we demonstrate NOR1 expression in endothelial cells and sub-endothelial cells of human atherosclerotic lesions. In response …

Investigation Of The Toxicity And Efflux Of Polychlorinated Biphenyls And Hydroxylated Polychlorinated Biphenyls In Escherichia Coli, Shen Geng

University of Kentucky Master's Theses

Polychlorinated biphenyls (PCBs) are persistent organic pollutants. Due to their properties, PCBs accumulate in the food-chain and post a threat to the health of human beings and wildlife. Hydroxylated PCBs (OH-PCBs) are oxidative metabolites of PCBs and are more hydrophilic than their parent PCBs. One of the best approaches to break down these contaminants is through bioremediation, which is an environmental friendly process that uses microorganisms to restore natural environment.

Towards this goal, we have investigated the toxicity and accumulation of PCBs and OH-PCBs in a Gram-negative bacterium, Escherichia coli. We have also determined the role played by a …

Comparison Of Digestive Function In Young And Mature Horses, Jennifer Elizabeth Earing

University of Kentucky Doctoral Dissertations

While forage plays an important role in equine nutrition, little research has been conducted evaluating fiber utilization by young horses. Therefore, studies were conducted to compare in vivo digestibility and digesta passage in weanlings and mature horses (Exp 1) and yearlings and mature horses (Exp 2). All horses were fed forage-based diets at the same rate (on a metabolic BW basis; Exp 1: 67% alfalfa cubes, 33% concentrate; Exp 2: 75% timothy cubes, 25% concentrate). Ytterbium labeled hay and cobalt-ethylenediaminetetraacetic acid were used to estimate digesta mean retention time (MRT), while in vivo digestibility (DM, OM, and NDF) was measured …

Network Drivers Of Intercustomer Social Support, Hulda G. Black

University of Kentucky Doctoral Dissertations

Customers in a service setting sometimes seek support from other customers; recent research has demonstrated this phenomenon. This research also found that intercustomer social support has a positive impact on consumer health, as well as the financial returns for the company. Given these positive effects for firms and customers, organizations can benefit from fostering social connections among their customers. While past research has investigated the positive consequences of intercustomer social support, little research to date has investigated the firm’s strategic role in fostering intercustomer social support. The current research seeks to understand key tactics a firm can use to promote …

Androgen Increases Angiotensin Receptor Type 1a On Smooth Muscle Cells To Promote Angiotensin Ii-Induced Abdominal Aortic Aneurysms, Xuan Zhang

University of Kentucky Doctoral Dissertations

The purpose of this study was to determine whether androgen promotes AT1aR expression on smooth muscle to confer high prevalence of AngII-induced AAAs in hyperlipidemic mice. In addition, we also investigate the role of androgen in the progression of established AngII-induced AAAs.

First, we sought to examine the role of endogenous androgen in the growth of established AngII-induced AAAs. By castrating male mice, we demonstrated that removal of endogenous androgen significantly decreased the progressive lumen dilation of established AngII-induced AAAs in male ApoE-/- mice, but had no effect on external AAA diameters. These results suggest that androgen contributes to the …

The Relationship Of Personality Preferences And Type To Health-Promoting Behaviors, Alcohol Use, And Cigarette Smoking, Billy Fredrick Martin

University of Kentucky Doctoral Dissertations

An individual’s personality traits and characteristics have been found to have an important relationship with health behaviors. However, there has been minimal research conducted with personality types. The purpose of the study was to examine the predictive relationship among MBTI® personality preferences and types and both selected health-promoting and selected risk-taking behaviors among residential college students. Furthermore, several potential mediating demographic variables were added to the study to determine their predictive relationship and if they should be entered into a model for the selected health behaviors.

The study used a cross-sectional design with two self-report instruments and demographic questionnaire. The …

“You’Re Surviving But I Don’T See How You’Re Living” Appalachian Women Talk About Tanf And Employment In Their Communities, Pon-Chu Tsou

University of Kentucky Master's Theses

This thesis studies qualitative data to examine the lived experiences of Kentucky Transitional Assistance Program (K-TAP) recipients in Appalachian Kentucky. This research suggests that PRWORA legislation utilize the importance of place-based analyses to implement and evaluate poverty policy. For women who are attempting to meet PRWORA’s goals, the local services available to the women and the barriers they face to employment highlight the role place has in this national policy discussion. Of the women interviewed, recipients who resided in economically distressed areas had fewer opportunities to participate in employment activities than women in at-risk or transitional areas. While many strived …

Effects Of Corticosterone And Ethanol Co-Exposure On Hippocampal Toxicity: Potential Role For The Nmda Nr2b Subunit, Tracy Renee Butler

University of Kentucky Doctoral Dissertations

Chronic ethanol (EtOH) exposure produces neuroadaptations within the NMDA receptor system and alterations in HPA axis functioning that contribute to neurodegeneration during ethanol withdrawal (EWD). Chronic EtOH exposure and EWD, as well as corticosteroids, also promote increased synthesis and release of polyamines, which allosterically potentiate NMDA receptor open-channel time at the NR2B subunit. The current studies investigated effects of 10 day EtOH and corticosterone (CORT) co-exposure on toxicity during EWD in rat organotypic hippocampal slice cultures, and alterations in function and/or density of the NR2B subunit of the NMDA receptor that may mediate CORT-potentiation of toxicity during EWD. We hypothesized …

Strategic Flexibility: Household Ecologies Of Ful’Be In Tanout, Niger, Karen Marie Greenough

University of Kentucky Doctoral Dissertations

(Agro)pastoralism in Sahelian Niger, as elsewhere, operates through household enterprises. Katsinen-ko’en (Fulбe) households, interconnected within kin and community networks, utilize a range of flexible strategies to manage a variety of ecological and economic risks. This dissertation argues that (agro)pastoralist households and communities maintain or improve viability in risky environments first by employing various mobility patterns, among other strategies, and relying on the tightly knit interdependence between household and herd. Secondly, households that most successfully sustain a cooperative integrity (i.e. partnerships between husband and wife, or wives, and parents and children) to negotiate decisions and strategies best withstand adversities such as …

Nongovernmental Organizations And Sex Work In Cambodia: Development Perspectives And Feminist Agendas, Jessica Catherine Schmid

University of Kentucky Master's Theses

This project focuses on nongovernmental organizations (NGOs) in Cambodia that deal, either directly or indirectly, with sex work and sex workers. The NGOs outlined in this study have goals ranging from preventing Cambodian women from entering the commercial sex industry to empowering Cambodian sex workers through the formation of sex worker unions. Through the textual analysis of documents and web materials disseminated by these NGOs and from interviews with representatives from the NGOs, I seek to analyze how underlying assumptions about development and about the commercial sex industry shape the ways in which the personnel leading these NGOs think and …

Fate Of Stable Isotope Label During Predation Of 15N-Tagged Wild-Type Escherichia Coli By Protozoa, Ashley M. Barton

University of Kentucky Master's Theses

Currently, bacterial movement in karst aquifers is not well understood. Use of stable isotopes to label non-pathogenic Escherichia coli as a particulate groundwater tracer in karst systems has been examined in previous studies. Loss of the stable isotope signal is anticipated in traces greater than 500 m in length. Potential loss of ¹⁵N due to predation by protozoa was examined. Filter-sterilized water from Royal Spring in Georgetown, Kentucky, was inoculated with a mixture of either Tetrahymena pyriformis or Colpoda steinii and ¹⁵N-enriched E. coli and stored in the dark at 14°C. Samples were analyzed for their nitrogen isotope …

Perceptions Of Support, Likelihood Of Retention, And Differences Between Places Of Origin Among First-Generation College Students, Teresa Radomski

University of Kentucky Master's Theses

First-generation college students are less likely to attend and complete college than their peers whose parents have completed college. Among the reasons cited for this disparity is lack of parental familiarity of the college admissions process and financial aid opportunities. First-generation youth wishing to pursue a college education must rely on others for this knowledge. This study examines first-generation college students' perceptions of support and whether their places of origin have any bearing on their future plans. The study examines interviews with participants through the lens of Tinto's (1993) model of student departure to examine whether their responses, and whether …

Microneedle-Assisted Transdermal Delivery Of Naltrexone Species: In Vitro Permeation And In Vivo Pharmacokinetic Studies, Mikolaj Milewski

University of Kentucky Doctoral Dissertations

Naltrexone (NTX) is a drug used primarily in the management of alcohol dependence and opioid dependence. Based on several drawbacks associated with the oral and injectable intramuscular dosage forms of naltrexone currently available on the market, there is substantial interest in delivering naltrexone transdermally. Although naltrexone does not permeate skin at the rate sufficient to reach therapeutic plasma concentrations in humans, novel flux enhancement methods such as microneedles help address this challenge. Earlier work in humans has demonstrated that the use of microneedles achieves plasma concentrations in the lower end of expected therapeutic values. Further flux enhancement is desired to …

Gene Expression Regulators Lin-11 And Let-711, In Modulating The Rate Of Aging And Lifespan, In C. Elegans., Tseten Yeshi Jamling

University of Kentucky Doctoral Dissertations

lin-11 and let-711 are early-developmental gene expression regulators with no previously known roles in aging regulation. Yet, they show strong aging-correlated expression profiles (Lund, Tedesco et al. 2002). lin-11 is strongly upregulated in very old worm populations, and let-711 is progressively downregulated in aging worm populations. Microarray studies were performed to identify their genome-wide targets, which were then subjected to further lifespan and genetic analysis to investigate their role in C. elegans aging.

The results indicate that the target pools of both lin-11 and let-711 are enriched for aging genes, since a significant number of tested genes increased lifespan. This …

Strategies For Targeting Lentiviral Vectors, Christopher Matthew Trimby

University of Kentucky Doctoral Dissertations

Lentiviral gene therapy has held great promise for treating a wide range of neurological disorders due to its ability to stably integrate into the genome of nondividing cells like neurons, in addition to dividing cells. The nervous system is a complex and highly heterogeneous system, and while a therapeutic intervention may have beneficial effects in one population of cells it may have severe side effects in another. For this reason, specific targeting of lentiviral vectors is crucial for their ultimate utility for research and clinical research use.

Two different approaches for focusing the targeting of lentiviral vectors were employed in …

The Effect Of Joint Mobilization On Functional Outcomes Associated With Chronic Ankle Instability, Matthew C. Hoch

University of Kentucky Doctoral Dissertations

Ankle sprains are among the most common injuries sustained by physically active individuals. Although ankle sprains are often considered innocuous in nature, a large percentage of individuals experience repetitive sprains, residual symptoms, and recurrent ankle instability following a single acute sprain; otherwise known as chronic ankle instability (CAI). In addition to repetitive ankle trauma, those with CAI experience reductions in functional capacity over the life span. This indicates that current intervention strategies for CAI are inadequate and require further investigation.

The objective of this dissertation was to explore differences in walking and running gait parameters between individuals with and without …