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Optimization Of Bacterial Luciferase For Expression In Mammalian Cells, Stacey Swiger Patterson

Doctoral Dissertations

This study describes the optimization of expression of the bacterial luciferase enzyme in mammalian cells. Previous attempts to express this heterodimeric enzyme complex in mammalian cells have been met with only modest success. In this research effort, several vector formats were evaluated to fully determine the optimal format for the expression of these genes. It was determined that the bacterial luciferase enzyme produced optimal bioluminescence in mammalian cells when the genes were cloned and expressed as a bicistronic transcript fused with an internal ribosomal entry site (IRES). To optimize the enzyme expression further, a novel approach to codon optimize the …

The Development And Utilization Of A Survey Instrument To Determine The Acceptance Of National Standards For Technological Literacy, Robert Malcolm Donan

Doctoral Dissertations

Over the past six years, practitioners in the field of technology education within the State of Tennessee have been mandated with nearly constant curricular change with the latest being the implementation of a revised set of content standards for technology education, a major change in programs within the curriculum framework, and most recently a new name for the state-wide program. These programmatic changes, other than the name change, although they addressed the majority of the national content standards for technological literacy, were not correlated with either the programs or grade level content explicit in the national standards developed and published …

Transgenic Approaches To Study Nodulation In The Model Legume, Lotus Japonicus, Crystal Bickley Mcalvin

Doctoral Dissertations

The soybean apyrase, GS52, characterized as an early nodulin, was further investigated for its possible role in nodulation. GS52 is expressed in roots and localized to the plasma membrane. In addition, it is rapidly induced upon rhizobial inoculation. Treatment of soybean roots with anti-GS52 antibodies blocked nodulation by Bradyrhizobium japonicum. Transgenic Lotus japonicus plants were generated expressing gs52 and showed enhanced nodulation and infection thread formation upon inoculation with Mesorhizobium loti that correlated with expression of the transgene. Surprisingly, expression of GS52 allowed L. japonicus plants to be infected but not nodulated by B. japonicum, the natural symbiont of soybean. …

Elucidation Of The Players And Events Regulating The First Meiotic Division In Mouse Spermatocytes, Amy Lynn Inselman

Doctoral Dissertations

Meiosis is the process that ensures the continued propagation of new organisms and is a source of genetic variability within a population. During meiotic prophase many dynamic rearrangements occur in the nucleus of the cell. These rearrangements include homologous chromosome pairing, recombination, synaptonemal complex breakdown, chromosome condensation and spindle assembly. The regulatory mechanisms behind these complex processes at the G2/MI transition have not been completely elucidated, preventing our complete understanding of the processes. The purpose of this work is to provide new insight to the events and players involved in the regulation of the G2/MI transition in mouse spermatocytes.

Part …

Broiler Performance And Mineral Utilization Of Enzyme-Supplemented Defatted Rice Bran Diet During Heat Stress, Ornprapun Puminn

Doctoral Dissertations

Defatted rice bran is a by-product from the solvent-extraction of rice bran. It contains high amounts of phytate and non-starch polysaccharides, which are considered to be two major antinutritional factors that limit the use of rice bran in poultry diets. Two experiments were conducted to evaluate broiler performance and mineral utilization of defatted rice bran diets supplemented with commercial enzyme phytase alone or a combination of phytase and xylanase under two different environmental temperatures. In the first experiment, six replicate groups of day-old chicks were assigned to five dietary treatments comprised of a control corn-soybean meal diet with 25% corn …

The Effects Of Retinol During In Vivo And In Vitro Oocyte Maturation And Embryonic Development., Tracy Elizabeth Livingston

Doctoral Dissertations

Previous studies demonstrated that retinol administration to ewes, followed by natural service, resulted in embryos with improved competence to develop in vitro. In vivo studies with sheep and in vitro experiments with bovine embryos, were designed to evaluate the effects of retinol and to understand its mechanism(s) of action.

The primary objective of the first experiment was to analyze ovine oocyte metabolism, and to assess the effects of retinol on this process. Sheep oocytes were matured in vitro over a 24 hour period in the presence of different radiolabeled substrates. Results revealed that oxidative metabolism measured by glutamine showed …

The Effects Of Dietary Additives On The Growth Performance And Occurrance Of Resistant Bacteria In Weanling Pigs, January Beth Pulliam

Doctoral Dissertations

Three replicate trials, with a total of 36 ileal cannulated pigs, were conducted to determine the effects of including carbadox or mannanoligosaccharides in weanling pig diets. Individual crossbred (Yorkshire X Landrace X Duroc) pigs were used as the experimental units and were weaned at approximately 21 days of age, balanced by gender, genetics and weight, and allotted to pens in groups of three. Pens were randomly assigned to one of four treatments including: AB) 55 mg carbadox/kg, BM) 0.2% phosphorylated mannanoligosaccharide, RT) a rotation of the above two treatments, or CT) NRC based control treatment with no additives. Pigs were …

Modeling Of The Inverse Heat -Conduction Problem With Application To Laser Chemical Vapor Deposition And Bioheat Transfer, Peng Zhen

Doctoral Dissertations

This dissertation consists of two parts. Part one deals with three-dimensional laser induced chemical vapor deposition (3D-LCVD), whereas part two deals with a Pennes model of a 3D skin structure. LCVD is an important technique in manufacturing complex micro-structures with high aspect ratio. In part one, a numerical model was developed for simulating kinetically-limited growth of an axisymmetric cylindrical rod by pre-specifying the surface temperature distribution required for growing the rod and then by obtaining optimized laser power that gives rise to the pre-specified temperature distribution. The temperature distribution at the surface of the rod was assumed to be at …

Population Genetics And Effective Population Size Of The Brazilian Free-Tailed Bat, Tadarida Brasiliensis (Chiroptera: Molossidae), Amy Louise Russell

Doctoral Dissertations

The Mexican free-tailed bat, Tadarida brasiliensis mexicana, exhibits variation in migratory behavior over its range. Some populations undergo seasonal long-distance migrations to warmer climates in winter, whereas others are resident through the winter in more northern regions and hibernate. Variation is also exhibited among populations in their migratory routes, and long-term banding studies document that populations are largely faithful to a single migratory route. These observations have led to the prediction that behaviorally defined migratory groups make up structured gene pools. Tests of this prediction using allozyme markers have documented high levels of gene flow among migratory groups, with …

Characterization Of Root Stimulating Bacterium And Its Root Stimulating Abilities, Anjana Rajen Sharma

Doctoral Dissertations

In this study, the characterization of a novel root stimulating bacterium (RSB) is reported and the root stimulating ability of RSB is compared to Sphingomonas and other related bacteria. A morphological examination of RSB was conducted. Nutritional and biochemical characterization was performed in order to obtain a profile of RSB. Pigment analysis indicated the presence of nostoxanthin, a pigment commonly found in Sphingomonas bacteria. Lipid analysis of RSB revealed the presence of sphingolipids in addition to other fatty acids suggesting similarity with other Sphingomonas bacteria. Pulse-field gel electrophoresis of RSB and Sphingomonas echinoides showed a high level of difference in …

Evaluation Of Microbial Inocula For Initiation Of Biological Life Support Systems For Wastewater Processing On Long Term And Deep Space Missions, Kimberly L. Cook

Doctoral Dissertations

A fundamental goal of ecological research is to better understand the relationship between structural diversity, functional diversity and ecosystem stability. Insight into the mechanisms that regulate microbial ecosystem function should provide important new information to improve system control for ecological, agricultural and biotechnological applications that depend on microbial processes. For example, defined microbial consortia have been employed to improve plant growth through enhanced nutrient uptake, production of plant growth promoting hormones or control of pathogens. However, a lack of consistency of results in field application has limited the widespread use of microbial inoculants. A major goal in rhizosphere studies, therefore, …

Species Diversity And Assembly History In Ecological Communities: Microcosm Experiments And Computer Simulations, Tadashi Fukami

Doctoral Dissertations

Despite its academic and applied importance, it has proven difficult to understand patterns of species diversity. This is in large part because multiple processes operating at various scales interact to influence diversity patterns emerging at different scales. Here I examine how the history of community assembly may interact with other ecological variables to influence species diversity. I consider four variables: the level of productivity, the size of ecosystem, the rate of dispersal, and the size of species pool. These variables have received considerable attention as major determinants of species diversity. However, their joint effects with assembly history remain largely unexplored. …

Body Condition Score And Dairy Form As Indicators Of Dairy Cattle Disease And Reproductive Performance., Chad D. Dechow

Doctoral Dissertations

The objectives of this research were to estimate heritabilities and correlations between body condition score (BCS) from various sources, determine the genetic relationship among BCS, dairy form, cow health and reproductive performance and investigate various models to analyze BCS and dairy form. BCS was obtained from herds using PCDART dairy management software and from linear type appraisals by Holstein classifiers. Cow health data was obtained from several herds recording disease treatments. Genetic evaluations for cow health in Denmark were also obtained. Reproductive data and yield data were provided by DRMS and AIPL-USDA. Heritabilities and correlations among traits were estimated with …

Identifying The Catalytic And Ligand Binding Roles Of Active Site Residues In Homotetrameric R67 Dihydrofolate Reductase, Michael Brad Strader

Doctoral Dissertations

R67 dihydrofolate reductase (DHFR) is a novel protein that confers clinical resistance to trimethoprim (TMP). Surprisingly, this R-plasmid encoded enzyme does not share homology with chromosomal DHFR. Recently a high resolution crystal structure of R67 DHFR has been solved. From this structure, R67 DHFR is a homotetramer that possesses exact 222 symmetry and a single active site pore that traverses the length of the protein (Narayana et al., 1995). Although this symmetry implies that four symmetry related binding sites must exist for each substrate, isothermal titration calorimetry studies indicate only two molecules bind. Three possible combinations of bound ligands have …

Factors Related To Condom Use Among Sexually Active African American Females Using Health Belief Model Constructs And Potential Cues To Action With A Mass Communication/Interpersonal Communication Approach, Shiree Monika Southerland

Doctoral Dissertations

The primary purpose of this study was to assess the factors that relate to male condom utilization among sexually active African American college women at The University of Tennessee.

College women between the ages of 18 to 24 are the most susceptible to contracting a sexually transmitted disease (STD) as they do not perceive themselves to be at risk. It is estimated that each year 12 million new cases of STDs occur and two thirds of those infected are under the age of 25 (Hale & Trumbetta, 1996). Women are among the fastest growing groups being infected with HIV. In …