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University of Kentucky

2017

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Articles 571 - 595 of 595

Full-Text Articles in Life Sciences

The Relationship Between Modifiable Lifestyle Factors And Muscle Lipid Depots In Older Adults, Maja Redzic Jan 2017

The Relationship Between Modifiable Lifestyle Factors And Muscle Lipid Depots In Older Adults, Maja Redzic

Theses and Dissertations--Pharmacology and Nutritional Sciences

Muscle health declines with age, influencing both muscle strength and performance. Modifiable lifestyle factors may mitigate muscle dysfunction by altering muscle lipid depots. Vitamin D status, dietary intake, and physical activity each play a role in muscle health during aging. Low vitamin D status (measured as 25(OH)D) is prevalent among older adults and has been associated with functional limitations and impaired physical performance. Previously, 25(OH)D concentrations were inversely associated with extramyocellular lipid (EMCL) and our lab observed a significant positive relationship between 25(OH)D concentrations and IMCL. Studies have shown mixed results regarding the effects dietary fat intake interventions have on …


Investigation Of The Mechanism Of Action For Mithramycin And The Biosynthesis Of L-Rednose In Saquayamycins, Stevi Weidenbach Jan 2017

Investigation Of The Mechanism Of Action For Mithramycin And The Biosynthesis Of L-Rednose In Saquayamycins, Stevi Weidenbach

Theses and Dissertations--Pharmacy

Natural products continue to be a major chemical lead matter for drug discovery due to their diverse chemical structures and bioactivities. Clinically significant natural products include anti-cancer and anti-infective compounds and while many more of these compounds show promising bioactivity, their clinical relevance is often limited by toxicity or poor solubility. Combinatorial biosynthesis can be employed to modify existing chemical scaffolds towards reducing these limitations. To fully take advantage of these biochemical tools, it is important to understand the biosynthesis and mechanism of action of the molecules.

Saccharides in glycosylated natural products provide specific interactions with cellular targets and are …


The Role Of Alternative Polyadenylation Mediated By Cpsf30 In Arabidopsis Thaliana, Guijie Hao Jan 2017

The Role Of Alternative Polyadenylation Mediated By Cpsf30 In Arabidopsis Thaliana, Guijie Hao

Theses and Dissertations--Plant and Soil Sciences

Drought stress is considered one of the most devastating abiotic stress factors that limit crop productivity for modern agriculture worldwide. There is a large range of physiological and biochemical responses induced by drought stress. The responses range from physiological and biochemical to regulation at transcription and posttranscriptional levels. Post-transcription, the products encoded by eukaryotic genes must undergo a series of modifications to become a mature mRNA. Polyadenylation is an important one in terms of regulation. Polyadenylation impacts gene expression through determining the coding and regulation potential of the mRNA, especially when different mRNAs from the same gene may be polyadenylated …


Evaluating Soil Physical And Chemical Properties Following Addition Of Non-Composted Spent Coffee And Tea For Athletic Fields, Shuang Zhou Jan 2017

Evaluating Soil Physical And Chemical Properties Following Addition Of Non-Composted Spent Coffee And Tea For Athletic Fields, Shuang Zhou

Theses and Dissertations--Plant and Soil Sciences

Physical and chemical properties of non-composted spent coffee (CF) and tea (T) suggest they may have applications as soil amendments for improving poor soils. Studies were conducted to determine 1) the effect of amendments on grass growth and soil properties, 2) the effect of incorporation versus surface application of amendments on soil properties, and 3) the effect of amendment application frequency on grass growth and soil properties. In the first study, amendments were mixed with sand and planted to bermudagrass. Treatments included CF, T, and peat moss (PM) mixed with sand, and 100% sand as a control. In the second …


Differences In The Muscle Activity For Baseball Hitters Of Varying Skill, Ethan M. Stewart Jan 2017

Differences In The Muscle Activity For Baseball Hitters Of Varying Skill, Ethan M. Stewart

Theses and Dissertations--Kinesiology and Health Promotion

INTRODUCTION: Muscle activity and timing of the swing phases may contribute to the differences we see in athletes at different skill levels. The purpose of this study is to analyze the differences between mean muscle activity, peak muscle active and time to peak muscle activity for select muscles in the lower extremity as well as the differences between start times for swing phases and bat velocity prior to impact for a skilled and recreational group. METHODS: Twelve healthy subjects were split into two groups based on competitive level and analyzed hitting off of a tee. RESULTS: No significant differences were …


The Default Mode Network And Executive Function: Influence Of Age, White Matter Connectivity, And Alzheimer’S Pathology, Christopher A. Brown Jan 2017

The Default Mode Network And Executive Function: Influence Of Age, White Matter Connectivity, And Alzheimer’S Pathology, Christopher A. Brown

Theses and Dissertations--Neuroscience

The default mode network (DMN) consists of a set of interconnected brain regions supporting autobiographical memory, our concept of the self, and the internal monologue. These processes must be maintained at all times and consume the highest amount of the brain’s energy during its baseline state. However, when faced with an active, externally-directed cognitive task, the DMN shows a small, but significant, decrease in activity. The reduction in DMN activity during the performance of an active, externally-directed task compared to a baseline state is termed task-induced deactivation (TID), which is thought to ‘free-up’ resources required to respond to external demands. …


Evaluation Of Pyriproxyfen Applied In Barrier Sprays For Mosquito Suppression, Andrea Glenn Skiles Jan 2017

Evaluation Of Pyriproxyfen Applied In Barrier Sprays For Mosquito Suppression, Andrea Glenn Skiles

Theses and Dissertations--Entomology

Despite advances in mosquito management, mosquito-borne disease in the United States is still of relevant public health concern and vector control is a top priority in preventing transmission of pathogens. Insecticide barrier sprays have become a common tool for suppression of mosquitoes in single-homeowner backyards. The application of the synthetic pyrethroid, lambda-cyhalothrin to perimeter vegetation with a backpack sprayer has been shown to significantly suppress mosquito levels for around 6 weeks. In an attempt to lengthen the effective duration of treatment, the IGR, pyriproxyfen, was added to a backpack mist blower with lambda-cyhalothrin, as adult mosquitoes exposed to pyriproxyfen have …


The Role Of Gln146 To The Stability And Activity Of Manganese Superoxide Dismutase, Ting Wang Jan 2017

The Role Of Gln146 To The Stability And Activity Of Manganese Superoxide Dismutase, Ting Wang

Theses and Dissertations--Chemistry

Gln146 is a highly conserved outer-sphere amino acid residue at the active site of MnSOD. It serves as a hydrogen bond donor to both the solvent molecules at the active site and Tyr 34, the conserved “gateway” amino acid residue. This dissertation develops our understanding of the effect of amino acid Gln146 at the second shell of the active site of metalloprotein MnSOD in facilitating metal binding, the modulation of redox potential, and the optimization of catalytic activity and structure stability. Different from the wild-type MnSOD, Q146E is always purified as a completely apo-protein with zero active metal ion and …


Oxidative Stress And Proteomic Studies Of Mammalian Models Of Age-Related Metabolic Dysfunction In Neurodegenerative Disorders, Aaron M. Swomley Jan 2017

Oxidative Stress And Proteomic Studies Of Mammalian Models Of Age-Related Metabolic Dysfunction In Neurodegenerative Disorders, Aaron M. Swomley

Theses and Dissertations--Chemistry

Expression proteomics is the field of science wherein proteins that make up the cellular proteome are identified both by name and by fold-change. Depending on the application of proteomics, this change in level could be due to internal cellular stressors or introduction of xenobiotics. Global oxidative stress measures use immunohistochemistry to determine the relative level of oxidative stress of macromolecules within the cell. In this dissertation, both global oxidative stress measures and expression proteomics were used in a variety of mammalian models in order to determine the effects of protein upregulation, intranasal insulin administration, and resveratrol supplementation on the cellular …


Illuminate The Pathway Of Membrane Protein Association And Degradation, Zhaoshuai Wang Jan 2017

Illuminate The Pathway Of Membrane Protein Association And Degradation, Zhaoshuai Wang

Theses and Dissertations--Chemistry

Escherichia coli transporter protein AcrB and its homologues are the inner membrane components of the Resistance-Nodulation-Division (RND) family efflux pumps in Gram-negative bacteria. It is well accepted that soluble proteins are only marginally stable, but such insight is missing for membrane proteins. The lack of stability data, including thermodynamic stability and oligomer association affinity is a result of intrinsic difficulties in working with membrane proteins. In addition, the degradation of soluble proteins in E. coli has been extensively studied whereas the degradation process of membrane proteins remains unclear. A focus of my thesis is the validation and development of methods …


Synthesis And Development Of Zwitterionic Pei (Zpei) For Optimized Delivery Of Nucleic Acids, Joseph Raleigh Duke Iii Jan 2017

Synthesis And Development Of Zwitterionic Pei (Zpei) For Optimized Delivery Of Nucleic Acids, Joseph Raleigh Duke Iii

Theses and Dissertations--Chemistry

Gene therapy holds promise for the treatment a wide range of diseases ranging from cystic fibrosis to cardiovascular disease to cancer. The need for safe and efficient gene delivery methods remains the primary barrier to human gene therapy. Non-viral vector materials, including polymers, can be designed to be biocompatible and non-immunogenic, but lack the efficiency to be clinically relevant. Gene therapy awaits the development of new materials that are both safe and efficient. Here, we have synthesized a series of modified zwitterionic polymers based on the common transfecting agent polyethylenimine (PEI). Using a variety of biochemical and biophysical methods we …


Metabolic Reprogramming Of Human Lung Cancer Cells And Ex Vivo Tissues Revealed By Uhr-Ftms Analysis Of Small Amino And Carboxyl Metabolites, Ye Yang Jan 2017

Metabolic Reprogramming Of Human Lung Cancer Cells And Ex Vivo Tissues Revealed By Uhr-Ftms Analysis Of Small Amino And Carboxyl Metabolites, Ye Yang

Theses and Dissertations--Toxicology and Cancer Biology

Studies were carried out to understand how human lung cancer cells and human ex vivo lung cancer tissues that are metabolically reprogramed compared with analogous non-cancer cells or non-cancer tissues. A Stable isotope resolved metabolomics (SIRM) approach was used to fulfill this aim by employing 13C, 2H or 15N labeled metabolic precursors like 13C6-Glc, 13C2-Gly, 2H2-Gly, 2H3-Ser, 13C5, 15N2-Gln to trace the flow of the labeled atoms into the down stream metabolic network. NMR and mass spectrometry are two …


Effects Of Chromium On Mouse Splenic T Lymphocytes And Effects Of Ethanol Exposure During Early Neurodevelopment On Behaviors In Mice, Lu Dai Jan 2017

Effects Of Chromium On Mouse Splenic T Lymphocytes And Effects Of Ethanol Exposure During Early Neurodevelopment On Behaviors In Mice, Lu Dai

Theses and Dissertations--Toxicology and Cancer Biology

The dissertation consists of three major projects with the focus on the immunotoxicity of chromium and the behavior disorders caused by early ETOH exposure respectively.

Hexavalent chromium [Cr(VI)] is widely used in various industrial processes and has been recognized as a carcinogen. As the first line of host defense system, the immune system can be a primary target of Cr(VI). T cell population represents a major arm of the immune system that plays a critical role in host anti-tumor immunity. Dysfunction of T cells compromises host anti-tumor immunity resulting in oncogenesis. Using mouse splenic T cells as an in vitro …


Exploring Predator-Prey Interactions In Agroecosystems Through Molecular Gut-Content Analysis, Kacie J. Athey Jan 2017

Exploring Predator-Prey Interactions In Agroecosystems Through Molecular Gut-Content Analysis, Kacie J. Athey

Theses and Dissertations--Entomology

Generalist predators can contribute to vital ecosystem services by potentially inducing trophic cascades as natural enemies of pests in agroecosystems. As the human population of the world gets larger, we need to produce more food on ever-smaller swaths of available land relying on ecosystem services, in the form of pest control, that may contribute to agricultural sustainability. Teasing apart the exact trophic linkages between predators and prey is a vital first step and essential to uncovering which predators are inducing trophic cascades and should be enhanced through conservation biological control.

Combined with ecological experimentation, the main tool used throughout my …


The Xenobiotic Transcription Factor Cap N Collar C Regulates Expression Of Multiple Insecticide Resistant Genes, Megha Kalsi Jan 2017

The Xenobiotic Transcription Factor Cap N Collar C Regulates Expression Of Multiple Insecticide Resistant Genes, Megha Kalsi

Theses and Dissertations--Entomology

Insecticide resistance is a global problem. Insecticide resistance management is very important, considering the time, effort, and cost of discovering and developing a new insecticide. There are diverse resistance mechanisms, but enhanced detoxification through overexpression of cytochrome P450s and target site insensitivity through mutation in insecticide binding site are the two most common mechanisms. The xenobiotic detoxification is divided into three successive phases (I, II and III), which ensures the metabolism and excretion of the detrimental toxins. Each phase comprises of a specific group of metabolizing enzymes such as P450s (phase I), GSTs (phase II) and ABC transporters (phase III). …


What Induces Female Kicking In Callosobruchus Maculatus? Disentangling The Effects Of Male Traits On Female Mating Decisions, William I. Licht Jan 2017

What Induces Female Kicking In Callosobruchus Maculatus? Disentangling The Effects Of Male Traits On Female Mating Decisions, William I. Licht

Theses and Dissertations--Entomology

Sexual conflict over mating duration drives the evolution of male and female adaptations that facilitate the manipulation of mating interactions in their favor. This conflict drives the evolution of traits that improve the fitness of the focal sex despite inflicting costs on mates. However, males can express multiple traits that increase and decrease female fitness simultaneously. When the effects of male traits on female fitness increase or decrease with duration of exposure, females traits that influence mating duration are selected upon. Females of Callosobruchus maculatus, a bruchid bean beetle, kick mates to forcefully end copulation. Although both negative effects …


Risk Parameters And Assessment Of Dietary Dsrna Exposure In Folsomia Candida, Jeffrey Edward Noland Jan 2017

Risk Parameters And Assessment Of Dietary Dsrna Exposure In Folsomia Candida, Jeffrey Edward Noland

Theses and Dissertations--Entomology

Assessing the risk of transgenic crop products is essential when determining the safety of a crop for deregulation and commercialization. The Organization of Economic and Cooperative Development (OECD), International Standards Organization (ISO), and governmental regulatory agencies require a battery of tests to demonstrate the safety of a GM product against several surrogate species of organisms that perform various ecosystem services. Assays are performed using toxicology methods established for pesticides. These methods have been applied to testing the safety, specificity and fate of Bacillus thuringiensis (Bt) Cry protein toxins engineered into crop plants and information exists on the effects on non-target …


Binding, Protection, And Rna Delivery Properties Of Porous Silica Nanoparticles In Spodoptera Frugiperda Cells, Emily Nadeau Jan 2017

Binding, Protection, And Rna Delivery Properties Of Porous Silica Nanoparticles In Spodoptera Frugiperda Cells, Emily Nadeau

Theses and Dissertations--Entomology

Traditional methods of pest control are threatened by the development of insecticide resistance, both to traditional insecticides and Bt toxins. Discovery of RNA interference (RNAi) has created opportunities to develop new insect control mechanisms. However, RNAi responses appear to be robust in coleopteran pests, but other orders, e.g. Lepidoptera and Hemiptera, present varied or ineffective RNAi responses. Current delivery strategies for double-stranded RNA (dsRNA) include microinjection, ingestion, and soaking. These approaches have benefits and problems. This study investigates the potential for porous silica nanoparticles (pSNPs) to improve the delivery of dsRNA and induce an RNAi response in Spodoptera frugiperda cells. …


Self-Reported Adherence To Physical Activity For Cancer Survivors: An Update From The 2015 Nhis Database, Andrew Jackson Shearer Jan 2017

Self-Reported Adherence To Physical Activity For Cancer Survivors: An Update From The 2015 Nhis Database, Andrew Jackson Shearer

Theses and Dissertations--Kinesiology and Health Promotion

Cancer is the second leading cause of death in America. It’s been suggested that regular physical activity (PA) can improve health outcomes in cancer survivors. An estimate from BRFSS data (2009) suggested that 47% of all cancer survivors met recommended guidelines and that this estimate was not different from the population at large (48%). Several factors were examined from these BRFSS data to determine whether subgroups of survivors existed who might benefit from interventions aimed at improving their PA status. The purpose of this investigation was to obtain more recent estimates of adherence to established PA guidelines for cancer survivors. …


Ecological, Molecular, And Morphological Data: A Synergistic Approach To Resolve Species Limits Of Lytopylus From The Area De Conservación Guanacaste, Costa Rica (Hymenoptera: Braconidae: Agathidinae), Ilgoo Kang Jan 2017

Ecological, Molecular, And Morphological Data: A Synergistic Approach To Resolve Species Limits Of Lytopylus From The Area De Conservación Guanacaste, Costa Rica (Hymenoptera: Braconidae: Agathidinae), Ilgoo Kang

Theses and Dissertations--Entomology

Lytopylus is species-rich genus of Agathidinae (Hymenoptera: Braconidae: Agathidinae), but limited information of the genus has been published. Morphological, molecular, and ecological data were compared to resolve the species limits of Lytopylus reared from caterpillars collected the Area de Conservación Guanacaste (ACG) in Costa Rica. Molecular data were initially used to hypothesize species limits, and morphological and host use data were employed to make a final decision when molecular data was indecisive, e.g., when the genetic difference between species was slight. Thirty-two new species are described with image plates of each species. Phylogenetic analyses of the barcode region of the …


The History Of The Federal Milk Marketing System And An Analytical View Of Unique Qualities Effects On Milk Prices In The Southeast, Owen Townsend Jan 2017

The History Of The Federal Milk Marketing System And An Analytical View Of Unique Qualities Effects On Milk Prices In The Southeast, Owen Townsend

Theses and Dissertations--Agricultural Economics

The Southeast Order has been milk deficit for over ten years and because of this milk has to be brought in from other orders to meet processor’s demand. Transportation credits provide processors with help to cover transportation costs to bring outside milk into the order. To help keep Class I utilization and support milk prices, relative to orders in the North, Order 7 has low diversion limits. As milk produced within Order 7 has been on a downward trend, milk brought into the order has not increased as consistently. In 2000 milk pooled from farms within the order made up …


An Analysis Of Factors Impacting Hay Auction Prices And The Potential For Nap To Reduce Alfalfa Revenue Risk, Madeline L. Dant Jan 2017

An Analysis Of Factors Impacting Hay Auction Prices And The Potential For Nap To Reduce Alfalfa Revenue Risk, Madeline L. Dant

Theses and Dissertations--Agricultural Economics

Hay auctions have generally been understudied due to their unique market structure. Therefore, the factors that influence the price of hay at auction markets are not well-known. The price of hay at auction markets reflects the various characteristics that differentiate each lot of hay sold. This study is aimed at analyzing the determinants of Central Kentucky hay prices. A hedonic price model is estimated using data collected from a Central Kentucky hay auction. Known hay attributes include forage species, form, bale weight, and nutritive value. An important aspect of this analysis is to determine whether the quality measures of the …


Investment For Trade? Impact Of Investment From Gulf Cooperation Council Countries On Trade, Sattam Faleh Almodarra Jan 2017

Investment For Trade? Impact Of Investment From Gulf Cooperation Council Countries On Trade, Sattam Faleh Almodarra

Theses and Dissertations--Agricultural Economics

The world has made great progress over the centuries through the massive increase in the interconnectedness of nations around the globe. Today, the world is connected through various ways, including the movement of goods, people, and money. The amount of goods traded across countries borders has drastically increased as the result of technological progress and the removal of barriers to trade. Not only has the world become more interconnected with the physical flows of goods and services, but also countries of the world have become more integrated financially. This study proposes to analyze how increase in financial flows, as measured …


Three Essays In Food Consumption And Health Related Issues, Fuad Mohammed Alagsam Jan 2017

Three Essays In Food Consumption And Health Related Issues, Fuad Mohammed Alagsam

Theses and Dissertations--Agricultural Economics

This dissertation consists of three essays that make contributions to the research on food consumption and health-related issues. Essay I elaborates on how the interactions of consumers’ beliefs and actions influence Food-Away-From-Home (FAFH) consumption and tests whether consumers compensate for the high caloric intake typically associated with FAFH by changing their behaviors during other meals. Essay II studies consumers’ choices related to time allocations for food consumption and tests how consumers’ lifestyles moderate the effect of secondary eating (eating while doing other activities) on obesity. Lastly, Essay III examines intertemporal choices, through which individuals make trade-offs between immediate gratifications and …


Three Essays On Food Safety Regulations And International Trade Of Agricultural Products, Jun Ho Seok Jan 2017

Three Essays On Food Safety Regulations And International Trade Of Agricultural Products, Jun Ho Seok

Theses and Dissertations--Agricultural Economics

This dissertation investigates food safety regulations and international trade of agricultural products dividing into three aspects: the signalling effect from U.S. strict food safety regulations on U.S. vegetable exports, political determinants of sanitary and photosanitary non-tariff barriers, and the impact of trade barriers on employment in developing countries. In chapter 2, we investigate the impact of high U.S. maximum residue limit (MRL) standards on U.S vegetable exports to 102 countries utilizing the hierarchical model. MRL, which is one of non-tariff barriers with respect to food safety, is applied to home and foreign countries at the same time. Thus, firms in …