Life Sciences Commons^™

A Multi-State Molecular Epidemiological Survey Of 16 Beef, Dairy, Poultry And Swine Farms To Facilitate Risk Assessment Of Listeria Monocytogenes, David Dean Rasmussen

Doctoral Dissertations

Listeria monocytogenes s an intracellular pathogen that poses serious risks for immuno-compromised individuals. On the farm risk assessment is needed to reduce exposure of such individuals to this pathogen. Base line epidemiological surveys for this pathogen are needed to identify common ecological reservoirs and sources. A 21 month survey of 4 animal farm types for L. monocytogenes in five different states was conducted to determine the level of occurrence in various environments. An overall occurrence of 1.4% (20/1432 samples) for L. monocytogenes was observed in this 21 month survey. Each sample type (soil, bedding/litter, feed/grass and animal rectal swabs) produced …

Immunotoxicological Study Of Depleted Uranium, Bin Wan

Doctoral Dissertations

The purpose of this study was to examine toxicity of depleted uranium (DU) to the immune system and the gene expression profile of DU-exposed immune cells including peritoneal macrophages, primary CD4⁺ T-cells and T Cell Hybridoma (TCH) PLP1 5B6. Flow cytometry analysis of annexin-V and Propidium Iodide (PI) binding revealed that DU causes death in those cells at various concentrations. The non-cytotoxic concentrations of DU determined in macrophages, primary CD4⁺ T-cells, and T cells hybridoma are 50µM, 100 µM, and 500 µM, respectively. Findings also revealed that DU-exposed macrophages are able to promote CD4⁺ T-cell proliferation in …

Antimicrobial Activity And Effect Of Selected Essential Oil Components On Cell Membrane Lipids, Valerie W. Ling

Doctoral Dissertations

The objectives of this study were to evaluate the antimicrobial activity of essential oil components (EOC) against Salmonella Typhimurium and Listeria monocytogenes and evaluate changes in bacterial membrane composition by observing changes in the fatty acids of Salmonella associated with exposure and adaptation to (or growth in the presence of) cinnamaldehyde (CIN) and carvacrol (CRV) EOC. Ten EOC were tested for efficacy using the broth microdilution and macrodilution methods. Beta-caryophyllene, limonene, alpha-pinene, and thymol were not lethal to Salmonella and Listeria at 2800mg/L. Dose-response models showed that the most effective EOC against Salmonella were CIN and CRV (50% probability of …

In Vitro Propagation, Regeneration, Attempted Tetraploid Induction, And Agrobacterium-Mediated Transformation Of Euphorbia Pulchurrima ‘Winter Rose’™, Kimberly Ann Pickens

Doctoral Dissertations

Poinsettia, Euphorbia pulchurrima, is the number one potted flowering plant in the United States. ‘Winter Rose’™ is a very popular cultivar with more than one million plants sold each year. To further improve this cultivar, particularly for larger flower heads and free branching, this research aimed at establishing some in vitro systems for application of biotechnology to poinsettia genetic improvement.

A protocol was established for in vitro axillary bud proliferation using greenhouse grown terminal buds. Buds were placed on Murashige-Skoog (MS) basal medium supplemented with benzlyaminopurine (BA). Explants produced the greatest number of axillary buds on medium containing between 2.2-8.8 …

Using A Bioluminescent Bacterial Bioreporter To Assess Iron Bioavailability In The Oceans, Cecile Elise Mioni

Doctoral Dissertations

Recent improvements in modern analytical methods have considerably increased our understanding of Fe biogeochemistry in the Ocean. Compiled data have shown that Fe concentrations are low in most open ocean surface waters and that the bioavailability of this Fe is influenced by organic complexation. Of presumed biotic origin, the importance of this organic complexation to Fe availability remains to be elucidated. Unfortunately, current analytical tools do not allow for a linkage to be established between Fe speciation to Fe bioavailability.

To supplement chemical analyses, we have developed a bioanalytical tool: a heterotrophic bacterial bioluminescent reporter system that responds quantitatively to …

Structure–Function Studies Of The Yeast Saccharomyces Cerevisiae Α–Mating Factor Pheromone Receptor Ste2p, Ayça Akal–Strader

Doctoral Dissertations

G protein–coupled receptors (GPCRs) are seven transmembrane domain cell surface proteins that respond to a variety of environmental cues. Response of these receptors to their cognate stimuli on the extracellular region of the cell results in a concurrent activation of a complex series of intracellular signaling pathways that prepare the cell for the required adjustments through regulation of gene expression levels. Participation of GPCRs in such intricate signal transduction pathways renders them important players in human diseases. The GPCR family of proteins therefore represents one of the largest classes of proteins to be targeted in the development of drug design …

The Role Of History In The Diversification Of The Funnel-Web Spiders, Agelenopsis Aperta, And Its Congeners, Nadia Antoine Ayoub

Doctoral Dissertations

Identifying the influence of history on the diversity of life is an important goal of evolutionary biology, whether it is an historical event that is extrinsic to the organism such as past climate change or an intrinsic event such as a single switch in behavior. Phylogenetic trees offer an indirect record of the history of diversification in a group of organisms and can be used in conjunction with other information to deduce the multiple roles of history affecting a particular group. Intra- and inter-specific phylogenetic relationships in the spider genus Agelenopsis Geibel (Araneae: Agelenidae) were analyzed using sequence data from …

An Analysis Of The End-Of-Life Choices Of Elderly Patients And Their Healthcare Providers At A Community Hospital In Tennessee, Elizabeth Harder Dobbins

Doctoral Dissertations

The Patient Self-Determination Act of 1990 was expected to popularize the use of advance directives (living wills and durable powers of attorney for healthcare (DPOA-HC)). Since the law was passed, researchers have found that the use of the documents has not increased as expected and that the documents, when present, were not always respected by healthcare providers.

The purpose of this study was to analyze the end-of-life choices of elderly patients and their healthcare providers in a community hospital setting. The subjects of this study were 160 patients, aged 65 years and older, who died in a community hospital in …

Online Atmospherics: An Investigation Of Feeling And Internet Purchase Intention, Kelly Price Rankin

Doctoral Dissertations

This study examines the online atmospheric cues of color and music and their impact upon feeling, attitude and purchase intention of consumers in the online environment. The research design was experimental and used data from a questionnaire. A pilot test of the instrument was conducted. The final questionnaire contained 39 items and a demographic section. A total of 200 questionnaires were collected. Participants were randomly assigned to one of four groups. Each group of 50 participants was exposed to a specific set of online atmospheric elements. The results indicated that Hypotheses 1, 3 and 4 were rejected while Hypotheses 2 …

Layer-By-Layer Self -Assembly For Enzyme And Dna Encapsulation And Delivery, Amish Patel

Doctoral Dissertations

Thin wall microcapsules were formed via Layer-by-Layer Self-Assembly of alternate adsorption of oppositely charged polyelectrolyte on microcores. After the core dissolution, empty polymeric shells with 20–25 nm thick walls were obtained. These microcapsules were loaded with Myoglobin, Hemoglobin and Glucose Oxidase by opening capsule pores at low pH and closing them at higher pH. The native structure of the enzyme was not affected due to different treatments. Biocompatible nanoshells were also prepared for encasing DNA. Using the same Layer-by-Layer Self-Assembly approach nanoparticle were constructed containing DNA as one of the layers. The nanoparticles of different architecture were used to deliver …

Modifier Of Mdg4 Encodes A Protein Involved In Homologous Chromosome Pairing In Drosophila Melanogaster Males, Morvarid Soltani Bejnood

Doctoral Dissertations

Our research interest is to uncover mechanisms underlying meiotic chromosome pairing and segregation. pairing failure 2 (pf-2) is a gene involved in this process during meiosis I of male Drosophila. The three pf-2 alleles recovered in a screen for chemically induced (EMS) mutations on chromosome III that cause paternal loss of chromosome IV display strong meiotic phenotypes. Cytological analysis of testes of pf-2 mutant flies revealed unpaired chromosomes at prophase and metaphase I and “laggard chromosomes” at anaphase I in primary spermatocytes. Meiosis II appears relatively normal. Genetic data confirm that non-disjunction occurs at the first meiotic division …

Systematics And Species Concepts In The Genera Lentinus Fr. And Panus Fr., With Emphasis On The Lentinus Tigrinus, L. Crinitus And Panus Lecomtei Complexes, Edward A. Grand

Doctoral Dissertations

The monographic work of Pegler (1983) on Lentinus has established the taxonomic guidelines for most recent studies involving members of the genus (Moncalvo et al. 2002, Rolen 2001, Krüger 2002). Pegler’s taxonomic hierarchy combined both Lentinus Fr. and Panus Fr. into one large genus, Lentinus Fr. The combination of these genera and its validity was one of the reasons for beginning this study. For generic level comparisons, ribosomal DNA sequence data can be helpful for determining relationships among taxa (Binder and Hibbett 2002, Hibbett and Vilgalys 1991, 1993, Hibbett and Donoghue 2001, Moncalvo et al. 2002, Thorn et al. 2000). …

Integrating Geographic Information Systems And Remote Sensing With Spatial Economic And Mixed Logit Models For Environmental Valuation, Aaron Raymond Wells

Doctoral Dissertations

This research focuses on the Emory and Obed Watersheds in the Cumberland Plateau in Central Tennessee and the Lower Hatchie River Watershed in West Tennessee. A framework based on market and nonmarket valuation techniques was used to empirically estimate economic values for environmental amenities and negative externalities in these areas. The specific techniques employed include a variation of hedonic pricing and discrete choice conjoint analysis (i.e., choice modeling), in addition to geographic information systems (GIS) and remote sensing. Microeconomic models of agent behavior, including random utility theory and profit maximization, provide the principal theoretical foundation linking valuation techniques and econometric …

Role Of Mitochondrial Uncoupling Protein 2 (Ucp2) In Modulation Of Adiposity, Xiaocun Sun

Doctoral Dissertations

Obesity is a disorder of energy balance in which energy intake exceeds energy expenditure. Methods to control obesity through limiting energy intake have had limited success, and it is widely recognized that energy expenditure must also be increased if long-term weight loss is to be achieved. Uncoupling proteins (UCPs) are a family of integral membrane proteins of mitochondrial inner membrane, where they uncouple the process of mitochondrial respiration from oxidative phosphorylation, diminishing the resulting production of ATP and decreasing the metabolic efficiency of the organism. Thus, UCPs provide new molecular targets for increasing energy expenditure. Unlike the other UCP family …

Biological Knowledge Discovery Through Mining Multiple Sources Of High-Throughput Data, Yu Chen

Doctoral Dissertations

As we are moving into the post-genomic era, various high-throughput experimental techniques have been developed to characterize biological systems at the genome scale. The high-throughput data are becoming fundamentally important resources to shed new insights on system-level understanding of the ‘organization’ and ‘dynamics’ of molecules (e.g. genes and proteins), relationships between them, interaction cascades, pathways, modules and various networks (i.e. regulation, co-expression and metabolism). This dissertation focuses on developing computational tools to facilitate the process of translating the ever-growing volumes of high-throughput data into significant biological knowledge on protein functions, pathways and modules.

Although high-throughput data provide a …

Group Differences In Safety Climate Among Workers In The Nuclear Decommissioning And Demolition Industry In The United States, Michael Everett Findley

Doctoral Dissertations

This study investigated group differences in safety climate among workers in the nuclear decommissioning and demolition (D&D) industry in the United States. The study population representative of workers in a high reliability industry included employees and subcontractors who worked at one of 10 locations in the United States managed by a multi-national corporation performing nuclear D&D operations. Safety climate was measured with a self-reported questionnaire, the Health and Safety Executive’s Health and Safety Climate Survey Tool (CST). The voluntary and anonymous responses totaled 1,587 out of an available population of 3,296 for an overall response rate of 48.1 percent. Significant …

Mechanisms Of Paracrine And Endocrine Actions Of Angiotensin Ii, Suyeon Kim

Doctoral Dissertations

Adipose tissue expresses high levels of angiotensinogen (agt), the only known precursor of Angiotensin II (Ang II) and we have previously shown that this hormone plays a paracrine role in regulation of adipocyte metabolism by increasing activity and gene expression of two key liogenic enzymes, fatty acid synthase (FAS) and glycerol-3-phosephate dehydrogenase (GPDH). However, molecular mechanisms by which Ang II regulates an adipocyte lipogenic gene, namely FAS and transcription factors mediating this regulation are largely unknown. Furthermore, signaling mechanisms whereby Ang II induces adiposity need to be further explored. Accordingly, our studies were designed to investigate transcriptional regulation of FAS …

A High -Order Finite Difference Method For Solving Bioheat Transfer Equations In Three-Dimensional Triple -Layered Skin Structure, Haofeng Yu

Doctoral Dissertations

Investigations on instantaneous skin burns are useful for an accurate assessment of burn-evaluation and for establishing thermal protections for various purposes. Meanwhile, hyperthermia with radiation is important in the treatment of cancer, and it is essential for developers and users of hyperthermia systems to predict, and interpret correctly the biomass thermal and vascular response to heating. In this dissertation, we employ the well-known Pennes' bioheat transfer equation to predict the degree of skin burn and the temperature distribution in hyperthermia cancer treatment.

A fourth-order compact finite difference scheme is developed to solve Pennes' bioheat transfer equation in a three-dimensional single …

Online Instruction Self-Efficacy Beliefs Among College Students Who Utilized Web-Enhanced Instruction, Carol Carter

Doctoral Dissertations

The main purpose of the study was to investigate online instruction self-efficacy beliefs among college students and the demographic influence of gender, classification rank, age, academic major, computer access, computer experience, online instruction experience, Internet experience, and the use of an online learning system.

The population of approximately 1000 students enrolled at Maryville College during Fall 2003 and Spring 2004 semesters was used to conduct the study. Students were asked to complete the Tennessee Online Instruction Scale (TOIS), which consisted of items related to forty online instruction tasks and background information.

Findings revealed that online instruction self-efficacy beliefs of students …

Families Practicing Sustainability: The Adoption And Maintenance Of Environmentally Responsible Behaviors In The Context Of Family Life, Brandis Brooke Judkins

Doctoral Dissertations

The lifestyles of contemporary Americans are threatening the sustainability of plant and animal life on earth. Unsustainable household choices related to food consumption, waste generation and disposal, transportation, energy use, and family planning are at the crux of the problem. However, there are a small number of American families that are committed to practicing a more environmentally sustainable lifestyle, and contrary to popular assumptions, sustainable behaviors are being practiced not only on rural homesteads, but in urban households as well. The purpose of the present research, therefore, was to identify the types of sustainable behaviors that a sample of these …

Ecology Of The Cerulean Warbler In The Cumberland Mountains Of East Tennessee, Charles Patrick Nicholson

Doctoral Dissertations

The objective of this study was to describe the distribution, local breeding densities and population trends, breeding biology, and habitat selection of the Cerulean Warbler (Dendroica cerulea) in the Cumberland Mountains of Morgan, Campbell, Scott, and Anderson Counties, Tennessee. Point counts were conducted during three years at six study sites. The Cerulean Warbler was detected at 50% of the point counts and was the sixth most frequently encountered bird. Spot-map censuses were conducted on five plots at three study sites. Cerulean Warblers occurred on all census plots at an average density of 84.9 pairs/100 ha. Average density on …

Relationships Between Spatial Enviromental Variability And Black Bear Occurrence In The Continental United States Of America, Donald Alfonso Martorello

Doctoral Dissertations

The American black bear (Ursus americanus) historically occurred throughout the forested regions of the continental United States of America (USA), and was absent only in central Nevada and portions of southern California and Arizona. Today, black bears only occur in a fraction of their former range, particularly in the Southeast where bear populations are highly fragmented and isolated.

Past research efforts have investigated the habitat preferences of black bears in several regions of the continental USA, but these studies were either limited to relatively small geographic areas or focused on selection preferences of individual bears. As a result, there is …

Relationships Between Spatial Environmental Variability And Black Bear Occurrence In The Continental United States Of America, Donald Alfonso Martorello

Doctoral Dissertations

The American black bear ( Ursus americanus) historically occurred throughout the forested regions of the continental United States of America (USA), and was absent only in central Nevada and portions of southern California and Arizona. Today, black bears only occur in a fraction of their former range, particularly in the Southeast where bear populations are highly fragmented and isolated.

Past research efforts have investigated the habitat preferences of black bears in several regions of the continental USA, but these studies were either limited to relatively small geographic areas or focused on selection preferences of individual bears. As a result, there …

Molecular Systematics Of North American Eupatorium, Kunsiri Chaw Siripun

Doctoral Dissertations

This study had two primary goals: first, to prepare a thorough taxonomic revision of North American Eupatorium, and second, to conduct initial evaluations using molecular techniques of how diploid and polyploid populations of Eupatorium rotundifolium and E. sessilifolium relate to one another. Nuclear ribosomal internal transcribed spacer (ITS) region and chloroplast DNA (trnC-psbM) sequences were used for molecular analysis, which allowed assessment of relationships of the polyploidy samples based on both a biparentally and a maternally inherited marker. The Inter Simple Sequence Repeat (ISSR) method was used for examining the relationships among diploid and polyploid populations …

The Effects Of Fe On Plankton In Hnlc Regions Of The World’S Oceans, Melanie Lynn Eldridge

Doctoral Dissertations

Ecosystem-scale productivity in many marine environments has been demonstrated over the last 15 years to be regulated by the biological availability of iron (Fe). Increasingly, more attention has been focused on coastal upwelling regions, like those off the coasts of California and Peru, since these areas are responsible for a disproportionately high contribution to new global production. A mosaic of nutrient gradients exists in upwelling regions, making them ideal sites for studies of nutrient affects on aquatic microbial communities. Paradoxically, both the California and Peruvian upwelling regions have also been shown to be Fe-limited. The present studies took place in …

The Development Of Optical Nanosensor Technology For Single Cell Analysis, Paul Misiko Kasili

Doctoral Dissertations

Advances in modern biosciences and optical biosensor technology have provided exciting new insights and capabilities. The integration of these fields has witnessed revolutionary advances, which include the development of optical nanosensors. Optical nanosensors are devices based on a direct spatial coupling between biologically active molecules and a signal transducer element interfaced to electronic equipment for signal amplification, acquisition and recording. Optical nanosensors consist of biorecognition molecules covalently immobilized onto the nanotips nanoscale optical fiber that serves as the transducing element. By combining the specificity of biorecognition molecules and the excellent sensitivity of laser-based optical detection, optical nanosensors are capable of …

Effects Of Weaning Transition And Ionophore On Metabolic Profile And Portal And Hepatic Nutrient Flux During Pre- And Post-Weaning Growth In Dairy Calves, James Levi Klotz

Doctoral Dissertations

Dairy calf weaning is associated with increases in ketone levels that exceed measured rates of utilization in adults and present a potential energy loss that may be mitigated by ionophores. Therefore, effects of weaning and ionophore supplementation on nutrient metabolism and growth in dairy calves pre- and post-weaning were examined in two experiments. The first experiment consisted of 24 Jersey bulls calves blocked in groups of two according to birth date and weight and randomly assigned to receive either a commercial pelleted starter (CON), or the same diet containing lasalocid (TRT; 83 mg/kg DM) to examine effects of weaning transition …

Fabrication, Characterization, And Chemical Sensing Of Silicon Dioxide Microcantilevers, Yanjun Tang

Doctoral Dissertations

The objective of this work is to design and fabricate an advanced silicon dioxide microcantilever sensor and to investigate chemical and biological sensing by microtechnology.

Microcantilever sensor technology has many advantages including fast response time, lower cost of fabrication, the possibility of sensor arrays with small overall dimensions, the ability to explore microenvironments, and improved portability for field applications. For all of these advantages, microcantilever chemical and biological sensors have drawn more and more attention.

So far, all other microcantilevers were designed and fabricated for AFM applications. We developed a novel SiO2 microcantilever especially for chemical and biological sensor applications. …