Digital Commons Network^™

The Role Of Viruses In Fe Recycling In The World's Oceans, Leo Poorvin

Doctoral Dissertations

Viral lysis is responsible for a significant fraction of bacterioplankton mortality in marine systems. This work shows that viral lysis of both heterotrophic bacterial and autotrophic cyanobacterial plankton releases iron (Fe) at a greater rate than is released from unlysed cells. These studies also show that the Fe released is bound to organic ligands, these ligands are not siderophores, and that these ligands have Fe binding stability constants similar to organic ligands found in seawater. Further, these studies have shown Fe released via viral lysis to be highly bioavailable to a range of model marine plankton and may potentially satisfy …

Understanding Immune Response In Mycobacterium Ulcerans Infection, Sarojini Adusumilli

Doctoral Dissertations

Buruli ulcer is a necrotizing skin infection and is the third most important mycobacterial disease in immune competent individuals after tuberculosis and leprosy in humid tropical countries. The causative agent Mycobacterium ulcerans is unlike other mycobacterial pathogens in that it appears to maintain an extracellular location during infection. Another unusual feature of the bacterium is that it is the only mycobacterium known to produce a dermo-necrotic polyketide toxin called mycolactone. A single Buruli ulcer, which can cover 15% of a person's skin surface, contains huge numbers of extracellular bacteria. The infection is characterized by massive necrosis at the site of …

Studies On The Role Of Specific Residues Of The Saccharomyces Α-Factor Pheromone Receptor (Ste2p) In The Inactive And Active State, Yong-Hun Lee

Doctoral Dissertations

G protein-coupled receptors (GPCRs) are a class of integral membrane receptor proteins that are characterized by seven-transmembrane (7TM) domains connected by intracellular and extracellular loops, an extracellular N-terminus, and an intracellular C-terminus. To date more than 1000 GPCRs have been identified, and these proteins recognize neurotransmitters, sensory molecules and chemotactic agents. These receptors are involved in the control of many aspects of metabolism and play important roles in diverse processes such as pain perception, growth and blood pressure regulation, and viral pathogenesis. Therefore, these proteins became important target for therapeutic agents and recent reports indicate that nearly 40% of drugs …

Examining Consumer Pre-Purchase Deliberation Process In An Online Marketplace, Hyung Chul Park

Doctoral Dissertations

The research objective of this study was to examine the consumer pre-purchase deliberation process in an online marketplace. Especially, examining the role of extrinsic quality (website-related quality), intrinsic quality (business operation-related quality), reputation of the retailer (other consumers’ opinions), attitude toward the retailer, and intention to transact with the retailer in an online marketplace context was main purpose of this study.

To collect the data, extensive online survey was performed. The data were analyzed through structural equation modeling test.

Findings revealed that there are significant positive relationships among extrinsic quality, intrinsic quality, reputation of the retailer, attitude toward the retailer, …

Analysis Of Vehicle Use Patterns During Military Field Exercises To Identify Potential Roads, Chunxia Wu

Doctoral Dissertations

Military training is an intensive land use and can cause negative environmental effects. Many studies conducted under Integrated Training Area Management (ITAM) for quantifying the impact resulted from the military training exercise found that off-road vehicular activities during training exercises cause the major impact to the training land. Vehicle land use patterns at a certain location affect the impact severity: concentrated and repeated traffic create more serious damage to the land compared to the dispersed offroad vehicle movements. Those areas heavily disturbed by off-road traffic may require a longer period of time or special treatments for the land to return …

High Resolution X-Ray And Neutron Crystallographic Studies Of Escherichia Coli Dihydrofolate Reductase, Brad C. Bennett

Doctoral Dissertations

Dihydrofolate Reductases (DHFRs) have been identified in nearly every proteome and are essential for most biosynthetic pathways involving one-carbon transfer reactions due to their recycling of tetrahydrofolate (THF). They catalyze the NADPH-dependent reduction of dihydrofolate (DHF), producing THF. Inhibition of DHFR ultimately depletes cellular pools of THF; causing a reduced supply of thymine nucleotides for DNA synthesis, resulting in genomic instability and cell death. Therefore, DHFRs remain important drug targets in antimicrobial and chemotherapeutic treatments. Despite exhaustive investigation of E. coli chromosomal DHFR, controversy persists over the dynamics of regulatory loops (the Met20, the βF-βG, and the βG-βH) and the …

Physical Activity Of Older Adults Residing In Different Levels Of Care, Randall Joseph Bergman

Doctoral Dissertations

This study compared the physical activity and functional levels of older adults residing in retirement (RH), assisted-living (AL) and nursing homes (NH). The StepWatch Step Activity Monitor3 (SW) pedometer was used to collect the number of steps taken during one day of activity. Activities of daily living (ADL) and instrumental activities of daily living (IADL) surveys were completed to measure functional status in terms of ADL problems and impairments. The sample consisted of thirty-seven older adults (17 RH, 8 AL, 12 NH, 71 – 94 years old) who wore the SW on the right ankle during a full day of …

Father Perspectives On The Relationship Between Family-Centered Practices And Empowerment Outcomes In Early Intervention, William Bryan Higgins

Doctoral Dissertations

The purpose of the present investigation was to explore fathers’ perceptions of family-centered practices in early intervention services and to examine how these practices influence fathers’ feelings of empowerment. Literature reviewed examined the family-centered approach to service delivery and empowerment outcomes, especially in early intervention programs. In addition, a brief discussion of fatherhood research was presented in an effort to inform potential hypotheses and discussion.

The current study was conducted as part of the Pathways to Family Empowerment Project whose purpose is to evaluate the family-centered model of service delivery in Tennessee’s Early Intervention System (TEIS). The data collected were …

Ligand Binding Studies In R67 Dihydrofolate Reductase And The Evaluation Of The Anion-Quadrupole Interaction At A Quantum Mechanical Level, Michael Robert Jackson

Doctoral Dissertations

Dihydrofolate reductases (DHFR) are important, ubiquitous enzymes catalyzing the hydride transfer from NADPH to dihydrofolate and producing the tetrahydrofolate intermediate that is essential for many metabolic processes, particularly for its role in DNA synthesis. R67 DHFR is a plasmid encoded enzyme that confers resistance to the antibiotic drug trimethoprim. This enzyme is active as a homotetramer. The active site pore possesses 222 symmetry as a result. This symmetry gives rise to a different mechanism by which it binds its ligands. There are potentially four symmetry related binding sites, but various studies have indicated only three possible combinations that include: two …

Cloning And Characterization Of Three Alleles Of The Mouse Furloss (Frl) Gene, Heather Marie Dech

Masters Theses

Single-gene mutations in the mouse serve as useful models for understanding the pathophysiology and molecular mechanisms of human diseases. Three dominant autosomal mutations affecting skin, hair and eye development in the mouse were recovered in mutagenesis experiments at the Oak Ridge National Laboratory. Previous work demonstrated that these mutations constitute an allelic series at the mouse Furloss (Frl) locus, and they were given the symbols Frl^a, Frlb and Frlc. The heterozygous phenotypes of all three mutants are similar; the mice appear normal at birth but gradually lose their hair until the hair follicles and sebaceous …

Seasonal Forage Availability And Diet Of Reintroduced Elk In The Cumberland Mountains, Tennessee, Jason Lee Lupardus

Masters Theses

The Tennessee Wildlife Resources Agency (TWRA) reintroduced elk (Cervus elaphus manitobensis) into the Cumberland Mountains, Tennessee over a 3-year period beginning in December 2000. We radio-collared 160 elk and monitored them by aerial telemetry from February 2001 to June 2003. Locations (n = 1450) were used in a geographic information system (GIS) to develop a core herd home range (789-ha sampling area) to assess elk seasonal forage use and availability. We monitored diet and resource availability from November 2003 to October 2004 by vegetation sampling and microhistological analysis of feces. Tall fescue (Festuca arundinacea; 35.1%) dominated …

Effect Of Chitosan And Water Soluble Chitosan Coatings On Quality Of Small Fruits, Jason Ki-Myung Noh

Masters Theses

Edible coating has been applied on the surface of fresh produce to extend shelf-life by suppressing respiration, transpiration, and microbial growth. The coatings, thus, can help decrease moisture and weight loss, and may offer a protective barrier against bacterial contamination and spoilage. Recent studies have indicated chitosan as an effective coating that extends shelf-life and improves a storability of fruits. The objective of this study was to demonstrate the effectiveness of natural biodegradable chitosan coatings in extending shelf-life and quality of fresh small fruits, such as blueberries and grapes. Fruits were dipped for 30 seconds in 1% chitosan in 1% …

Effect Of Long Term Resistance Training On A Senior Population With Trained Peer Leadership, Richard John Burke Iii

Masters Theses

Purpose: The goal of this study was to examine the physical effects of a two-year peer-led resistance training and aerobic program in a group of community dwelling older adults.

Methods: Nine community-dwelling older adults (Age = 81.2 ± 7.1 yrs; Males = 1, Females = 8) were trained for six weeks, monitored and corrected for one year, and then completed two years of peer-led weight training three days/week. Pre and post training physical function assessments included 6-minute walk distance (endurance, functional mobility and gait speed), 8 foot timed up-and-go (balance and agility), back scratch (shoulder flexibility), sit-and-reach (flexibility), number of …

Human Equivalent Dose Modeling For Omega-3 Fatty Acid Supplementation In C57bl/6j Mice, Laura Louise Jones

Masters Theses

The rodent model is often used to study the impact of dietary n-3 fatty acids on a variety of biological endpoints, and the results of these studies have been used to explain anticipated effects of n-3 fatty acid intake in humans. However, supplemental levels of n-3 fatty acids that are commonly used in rodent studies do not represent reasonable human intake, by comparison. Currently there is no standard method for the addition of n-3 fatty acids to rodent diets. We tested a mathematical model for dosing supplemental levels of α-linolenic acid (ALA) and eicosapentaenoic acid (EPA) to rodent diets on …

Tennessee Hay Supply And Demand Response To Prices And Other Factors, Jon Edwin Travis

Masters Theses

The hay industry in Tennessee closely resembles a perfectly competitive market. There are no substantial barriers to market entry and farmers can freely exit if they so choose. A large number of firms and consumers (livestock producers and equine operators) exist. Hay is a fairly homogeneous product; although hay varieties are not identical, in many livestock production situations they are close substitutes. Producers are price takers in the market.

Currently, more information is needed regarding Tennessee hay supply and price response. The objectives of this study were: 1) to determine the factors that influence Tennessee hay acreage and yield, 2) …

Ruffed Grouse Habitat Use, Reproductive Ecology, And Survival In Western North Carolina, Benjamin Colter Jones

Doctoral Dissertations

Ruffed grouse populations are lower in the Appalachians compared to the Great Lakes states, the geographic core of grouse distribution. Theories to explain lower numbers in the Appalachians include inadequate foods, lower reproduction, lower survival, and loss of habitat. To provide insight into ruffed grouse ecology in the Appalachians, habitat use, reproduction, and survival were studied on Nantahala National Forest in western North Carolina. Radiotagged grouse (n = 276) were monitored through the year. Seasonal 75% kernel home ranges (n = 172) averaged 15–59 ha across sexes, ages, and seasons. Home range size was related to habitat with …

Reverse Genetics With Tilling In Phytophthora Sojae, Melinda Beth Tierney

Masters Theses

The reverse genetic method TILLING (Targeting Induced Local Lesions in Genomes) is being applied to the plant pathogen Phytophthora sojae. The objective is to recover gene-specific mutants carrying allelic series and/or knockout induced mutations.

A library of 3000 mutant individuals was generated using the chemical mutagens ethylmethanesulfonate (EMS) or ethylnitrosourea (ENU). Gene-specific induced mutations are detected by screening a mirror library of genomic DNA. PCR is used to amplify and fluorescently label 1kb portions of specific genes from the mutant library and the PCR products are then heated and cooled slowly to form hetero- and homoduplexes.

The PCR fragments …

The Bovine Coronavirus 2'-O-Methyltransferase Binds Cis-Acting Stem-Loop Iv In The 5-Prime Untranslated Region Of The Viral Genome, Tara Beth Tucker

Masters Theses

The positive-stranded coronavirus genome, at 32 kilobases in length, is the largest known viral RNA genome, and internal cis-signaling elements directing its replication have been described only within the last ten years. The bovine coronavirus genome encodes 26 proteins in the region between the 5’-terminal 210-nt untranslated region and the 3’-terminal 298-nt untranslated region. Here, genes for 5 of the 26 proteins were cloned into bacterial expression plasmids for the long-term goals of characterizing enzymatic and RNA binding properties. These genes encode enzymes postulated to interact directly with the cis-acting RNA elements and carry out RNA synthesis, namely, the …

Potential Of Beauveria Bassiana 11-98 As A Biological Control Agent Against Tomato Pests; And Detection Of The Mycotoxic Metabolite Beauvericin In Tomato Plants Using Hplc, Wesley Aaron Powell

Masters Theses

Beauveria bassiana (Balsamo) Vuillemin is an entomopathogenic fungus with an extensive insect host range. The isolate Beauveria bassiana 11-98 also endophytically colonizes tomato and cotton plants. In our research, B. bassiana 11-98 was evaluated for its potential to control insect pests of tomato in laboratory assays. Potato aphids, Macrosiphum euphorbiae (Thomas) exposed to different formulations of B. bassiana 11-98 coniidia in direct contact and contact-while-feeding assays using target concentrations of 1 x 10⁴, 10⁵, 10⁶ and 10⁷ conidia/ml. After exposure for 10 days, aphid mortality did not exceed 40% and rate of reproduction was …

Temporal Relationships Between Plasma Cortisol, Corticosteroid-Binding Globulin (Cbg), And The Free Cortisol Index (Fci) In Pigs, Rebecca Jackson Adcock

Masters Theses

The free fraction of cortisol in circulation is that which is biologically available to cells. In swine, more than 60% of cortisol is bound to its carrier glycoprotein, porcine corticosteroid-binding globulin (pCBG). The Free Cortisol Index (FCI), which is the ratio of total cortisol to CBG concentrations, has been shown in humans to correlate well with free cortisol. In experiment one, the relationship between plasma free cortisol and the free cortisol index (FCI) was evaluated in 8-wk old pigs over a 24 h period and in response to the administration of saline (n = 4) and ACTH (n = 4). …

An Evaluation Of The Effects Of Small, Man-Made Impoundments On Stream Macroinvertebrate Communities And Water Quality In Eastern Tennessee, Larry Eugene Everett Jr.

Masters Theses

Semi-quantitative benthic macroinvertebrate samples were collected from riffles above and below four small impoundments in eastern Tennessee. Watershed and habitat surveys and a variety of field measurements were performed for each sample site and each sampling event when appropriate. Samples were collected quarterly (seasonally) during a one-year period. The goal of the study was twofold: (1) to determine whether or not differences in stream macroinvertebrate communities above and below impoundments existed and if so, (2) to attempt to evaluate the possible effects of the impoundments on the downstream benthic community and water quality.

One-hundred and fifty-four distinct macroinvertebrate taxa in …

The Subcellular Targeting And In Vivo Metal Binding Characteristics Of Agnt84 Using Transgenic Tobacco And By-2 Suspension Cell Cultures, Brook Kay Nelson

Masters Theses

AgNt84 is a nodulin protein expressed in Alnus glutinosa, an actinorhizal tree that participates with the actinomycete Frankia in symbiotic nitrogen fixation. Expression of AgNt84 mRNA is exclusively found within Zone 2 of the nodules, which is the zone that contains cells in the process of being infected by Frankia. A truncated form of the protein was found to bind Zn²⁺, Ni²⁺, Co²⁺, Cu²⁺, Cd²⁺, and Hg²⁺ in vitro. AgNt84 was predicted to be targeted extracellularly based on the presence of an N-terminal signal sequence. The purpose …

Validation Of Quantitative Trait Loci Conditioning Seed Phytate And Protein Concentration In Soybean [Glycine Max (L.) Merrill], Andrew M. Scaboo

Masters Theses

The concentration of phytate, a mixed cation salt of phytic acid (myo-inositol 1,2,3,4,5,6-hexakisphosphate), is an important consideration when analyzing grain for livestock feed rations. A discovery that SSR marker Satt237 and Satt561 are associated with quantitative trait loci (QTL) for phytate content in soybean [Glycine max (L.) Merr] has been made recently. The objectives of this study were to 1) confirm those QTL in independent segregating soybean populations, 2) compare the effectiveness of marker assisted selection (MAS) or dual MAS and phenotypic selection for seed phytate and protein concentration in soybean, and 3) assess the agronomic …

Brassica Mulches And Meal Control Fungal Wheat Pathogens In Vitro And Take-All Disease In Soil, Thomas Samuel Breeden

Masters Theses

Soilborne pathogens have an economic impact on crops throughout the world. Many survive saprophytically and therefore are difficult to control. Soil fumigation and seed treatments are sometimes effective. However, they are economically impractical for many crops. Crop rotation/alternative crops are often a practical, economical, and successful means of controlling soilborne pathogens. Recent studies have revealed that Brassica spp. Inhibit a wide array of plant pathogens. Decomposing species of Brassica release glucosinolates, which are converted to isothiocyanates (ITC) by the enzyme myrosinase. The ITC compounds inhibit microorganisms. The present study had three objectives. The first was to evaluate the effect of …

Competing For Legitimacy: The Development And Evolution Of Forest Certification In Finland, Keith Wellington Mars

Masters Theses

Forest certification in Finland has developed and evolved in favor of the Programme for the Endorsement of Forest Certification Schemes (PEFC) and not the Forest Stewardship Council (FSC). The Finnish Forest Certification System (FFCS as endorsed by PEFC) certification of forests in Finland has been achieved at an unprecedented rate and scale. This event, both in process and outcome, was highly contentious and politicized. Finland represents a microcosm of the current issues in forest certification and is ripe for study. However, few attempts have been made to explain why and how forest certification develops and evolves. This thesis sheds light …

Brooklyn Botanic Garden’S Children’S Gardening Program: A Survey Of Alumni, Emily Kathleen Smith

Masters Theses

Among public gardens, Brooklyn Botanic Garden (BBG) hosts the oldest children’s gardening program in the United States. Founded in 1914, the Brooklyn Botanic Garden Children’s Gardening Program (BBG CGP) has succeeded in involving a steady flow of children year after year, creating an environment where children have the opportunity to interact with nature. Approximately 35,000 children have participated in the BBG CGP since its inception in 1914. A mail survey was conducted of alumni of the BBG CGP in the spring of 2005 to identify how the program has affected their adult lives. A random sample of 700 participants was …

Low-Dose Radiation Effects On Variation In Gene Expression, With Potential Application To Network Construction, Adam Tebbe

Masters Theses

The molecular responses to radiation exposure have been an avidly pursued research topic for many years now. Most of this effort has been focused on large doses of radiation, such as those experienced during a nuclear explosion or cancer treatment. Of equal importance though, are the effects of low doses of radiation, which have received much less attention. This study attempts to analyze the effects of low-dose radiation exposure on different inbred mice strains, each of which represents a unique genetic constitution. The genetic background was found to have a dramatic effect on the variability of gene expression of the …

A Sanitation Assessment Of Food Contact Surfaces In Child Care Centers Using Microbiological Analysis And Rapid Sanitation Assays, Catherine Moore Cosby

Masters Theses

Food contact surfaces are a major concern for food service facilities in controlling the spread of foodborne pathogens. Food service areas within these facilities are considered critical to health, and therefore the microbiological quality of these surfaces within child care center food service areas must be surveyed and assessed. The main objectives of this study were: (1) to gather information as to the environmental microbiological quality of food service surfaces and a non-food contact surface in child care centers, and (2) to evaluate several rapid sanitation assays for determining the sanitation quality of food contact surfaces and to determine if …

Project Green Reach At Brooklyn Botanic Garden: A Case Study Of The Summer Program, Susan Conlon

Masters Theses

This study examined Project Green Reach (PGR), one program of the Children’s Education Program at Brooklyn Botanic Garden (BBG). Located in Brooklyn, NY, BBG is a public garden that has served as a model program for garden-based youth education since 1914. PGR utilizes both the indoor classroom and outdoor laboratory to engage K-8 students and teachers at Brooklyn’s Title I schools in informal learning about science. Every year, PGR instructors select a small group of students into the summer program where they work in teams on garden and science projects at BBG. A case study was conducted to document PGR’s …

Relationship Of School Breakfast Environment And Participation To Child Dietary Intake And Body Weight In Five Rural Appalachian Schools, Andrea Leigh Graves

Masters Theses

Objective The purposes of this study were two-fold: 1) to assess the school breakfast environment at four rural Appalachian schools for the contribution of foods to calories, fat, and fiber; and 2) to assess the dietary intake of students in these schools in relation to where breakfast was consumed (home, school, or both places) and by student weight status.

Setting Four rural Appalachian schools with fourth and fifth grade students in East Tennessee.

Subjects 255 fourth grade children completed a 24-hour dietary recall with a trained NDS-R interviewer and were weighed and measured by the Coordinated School Health Program.

Design …