Life Sciences Commons^™

Native Plant Establishment Success Influenced By Centaurea Stoebe Control Method, Laurelin Marie Martin

Masters Theses

Invasive species frequently hinder restoration efforts. While the effectiveness of differing control methods are often reported, the impacts these methods have on the establishment of a native plant community are often unknown. To determine methods that effectively reduce spotted knapweed (Centaurea stoebe) while enhancing native species establishment, we tested 12 treatment combinations consisting of an initial site preparation (mowing, mowing + clopyralid, or mowing + glyphosate), with combinations of annual adult knapweed hand pulling, and/or burning. We established 48 plots and applied site preparation treatments during summer 2008, seeded 23 native forbs and grasses during spring 2009, pulled …

Climate Change And Metapopulation Implications For Species Re/Introductions: A Spatial Analysis Of Suitable Habitat For The American Marten (Martes Americana) In Northern Michigan, Joshua Michael Green

Masters Theses

The American marten (Martes americana), which was extirpated from Michigan by 1939 due to logging and trapping, has cultural significance as a clan animal to Great Lakes Native American Tribes and ecological significance as a forest health indicator. Sleeping Bear Dunes National Lakeshore (SBD) is considering reintroduction, but several factors must first be considered in assessing the habitat suitability. The goals of this study were to 1) enhance an existing habitat suitability model by including additional relevant variables, 2) conduct a spatial analysis of the habitat within the study area using a metapopulation perspective and 3) incorporate climate …

The Performance Of Bacterial Phytosensing Transgenic Tobacco Under Field Conditions, Michael Harrison Fethe

Masters Theses

Currently the platforms for wide-area detection of environmental contamination are limited. Therefore, there is interest in developing new platforms, especially for use in crop plants to detect and report the presence of biotic and abiotic stress agents. A biosensor uses a biological organism or substrate to detect the presence of an elicitor (i.e., heavy metal, TNT, or bacteria). The foundational groundwork to create biosensors in transgenic plants exists. The creation of bacterial phytosensing transgenic tobacco containing an orange fluorescent protein (OFP) reporter driven by synthetic pathogen-inducible promoters provides a fluorescent signal when infected with phytopathogens for earlier detection in the …

Maximizing Lignin Yield Using Experimental Design Analyzing The Impact Of Solvent Composition And Feedstock Particle Size On The Organosolv Process In The Presence Of Feedstock Contamination, Hagen Maraun

Masters Theses

The depletion of fossil feedstock and the unfavorable environmental effects accompanying by its exploitation are the driving forces in the process of transitioning to renewable feedstock as the primary resource. Similar to petrorefineries, a new modern biorefinery would use biomass to produce a variety of different chemical products and transportation fuels. Lignin, a potential low-cost, high volume output process stream derived from lignocellulosic biomass is currently being researched to better support the economics of the future biorefinery. In this study, experimental design was used to determine the optimal level for each process factor in an organosolv fractionation process that targets …

Demonstration Of A Targeted Proteome Characterization Approach For Examining Specific Metabolic Pathways In Complex Bacterial Systems, Adam Justin Martin

Masters Theses

Multiple Reaction Monitoring (MRM) is a powerful tandem mass spectrometry (MS/MS) tool frequently implemented in proteomic studies to provide targeted analysis of proteins and peptides. The selectivity that MRM delivers is so strong that it provides the quadrupole mass spectrometers (QQQ), on which it is commonly employed, with pertinence to proteomic studies that they would otherwise lack for their relatively low resolution. Additionally, this increased level of selectivity is sufficient enough to supplant complicated fractionation techniques, additional dimensions of chromatography, and 24 hour long MS/MS experiments in simplistic biological samples. But there is a deficiency of evidence to determine the …

Inhibition Of Spoilage Yeasts Using Spice Essential Oils And Their Components, Audra Ann Wallis

Masters Theses

Clove bud, cinnamon bark, and thyme oil, along with their components cinnamaldehyde, cinnamic acid, eugenol, carvacrol, and thymol, are widely acknowledged to have antimicrobial properties against bacteria. However, less is know about the inhibitory properties of essential oil components against spoilage yeasts. In this study a minimum inhibitory concentration (MIC) for these essential oils and components was determined using an agar dilution assay for Torulaspora delbrueckii, Candida krusei, Schizosaccharomyces pombe and Zygosaccharomyces bailii. The efficacy of essential oil components eugenol, carvacrol, cinnamaldehyde and thymol then were evaluated in a model salad dressing. The MIC against all yeasts for cinnamaldehyde and …

Hydrogeology Of The Little River Animal Agriculture Environmental Research Unit And Impacts Of Dairy Operations On Groundwater, Robert Wesley Hunter

Masters Theses

This thesis describes the development of an integrated hydrogeologic/hydrologic site assessment and groundwater/surface water quality monitoring program at the University of Tennessee – Little River Dairy Farm, located near Townsend, TN. Hydrologic/hydrogeologic investigations of streams and groundwater at the site have been underway for more than 5 years, and these are expected to provide background data for assessing impacts of dairy wastes. The lower half of the ~180 ha site consists of low-relief fields used for row crops, which are underlain by 4 – 9 m of alluvial deposits on top of black shale or limestone that include sinkhole features. …

Practitioner Rankings Of Entry-Level Competencies For Public Health Nutrition, Courtney Teal Schand

Masters Theses

Background: The Association of Graduate Programs in Public Health Nutrition’s graduate competencies were updated and refined by an expert panel and a survey of Public Health Nutrition (PHN) academicians, which resulted in 58 proposed competencies in five domains, Food and Nutrition Science, Advocacy, Research and Evaluation, Communication and Cultural Competency, and Management and Leadership.

Objectives: The objectives of this study were 1) to determine if differences existed in calculated domain scores of practitioner rankings of essentiality for the PHN graduate competencies by demographic variables of interest (current position, years of experience, education, and/or intent to retire); 2) to determine the …

Bovine Mammary Interleukin-8 Receptor Expression And Genetic Association With Streptococcus Uberis Based Mastitis., Lydia Jean Siebert

Masters Theses

Mastitis is an economically distressing disease in the dairy industry. Bacterial pathogens enter the gland and encounter cell types that release immune mediators including interleukin (IL)-8. IL-8 has two membrane bound receptors: CXCR1 and CXCR2. CXCR1 and CXCR2 are expressed on neutrophils and other cell types in other species but their expression is unknown in the bovine mammary gland. To test this, mammary tissue samples from six Holstein dairy cows were subject to dual immunofluorescence with bovine specific CXCR1 and CXCR2 antibodies and cell type markers. CXCR1 was expressed on alveolar epithelial cells, fibroblasts, and leukocytes. CXCR2 expression was identified …

Population Demographics And Genetic Structure Of Black Bears In Coastal Louisiana, Jesse Charles Troxler

Masters Theses

The range and abundance of the Louisiana black bear (Ursus americanus luteolus) were greatly diminished during the 20th century. This subspecies was reduced to 3 small, isolated subpopulations in Louisiana as bottomland hardwood habitat was converted to agriculture. These bears were listed as threatened by the U.S. Fish and Wildlife Service in 1992 and a recovery plan was published in 1995. Recovery requires estimates of population parameters to evaluate current population status and future viability. I conducted a mark-recapture study from 2010 to 2012 to estimate demographic parameters of the coastal population of Louisiana black bears. Because inbreeding …

Forage And Biomass Dual-Purpose Harvest System Using Native Warm-Season Grasses, David Weston Mcintosh

Masters Theses

There has been increasing interest in utilizing native warm-season grasses (NWSGs), especially switchgrass, as a biomass feedstock for cellulosic ethanol production. Millions of hectares of crop and pasture in the mid-South are forecast to potentially be planted with switchgrass for biomass feedstock production. This could have a substantial impact on the region’s cattle industry, reducing forage production hectares. This study was conducted to determine the effect of early season harvest timing on forage and biomass of NWSGs designed for use in cellulosic ethanol production. The over-all hypothesis was to determine if an early forage harvest can be included in a …

Antimicrobial Activity Of Essential Oils And Their Components Against Lactic Acid Bacteria, Laurel Dunn Gann

Masters Theses

Efficacy of plant essential oils against spoilage lactic acid bacteria was examined using two different study methods with the goal of determining minimum inhibitory (MIC) and minimum lethal concentrations (MLC) of the essential oils. The initial study included the incorporation of the essential oils, or their major constituents, into agar to allow uniform dispersion of the substance throughout an agar surface. Individual cultures of nine lactic acid bacteria species (Pediococcus acidilactici, Pediococcus damnosus, Lactobacillus fermentum, Lactobacillus fructivorans, Lactobacillus brevis, Lactobacillus buchneri, Lactobacillus plantarum, Leuconostoc mesenteroides, and Leuconostoc citrovorum) were spot …

Producers Willingness To Adopt A Prescribed Grazing System East Of The 100th Meridian, Caroline Elizabeth Holt

Masters Theses

With the climate change concerns facing the United States, the contributions of the beef industry to greenhouse gasses are difficult to overlook. The agriculture industry is estimated to be the largest producer of methane emissions in the United States, and within agriculture, livestock are the largest contributor with cattle producing 73 percent of the methane emissions from all livestock (Johnson and Johnson 1995).

This thesis focuses on factors influencing beef cattle producers’ east of the 100th meridian interest in adopting prescribed grazing; including how a government cost share system could enhance adoption. Information was obtained for the study through a …

Development Of Novel Vaccines For Campylobacter Control In Poultry, Lindsay Ann Jones

Masters Theses

Campylobacter is the leading bacterial cause of human enteritis in developed countries. Human campylobacteriosis is commonly associated with consumption of undercooked, contaminated chicken, a natural host of Campylobacter. Thus, control of Campylobacter colonization in poultry at the farm level would reduce the risk of human exposure to this pathogen. Vaccination is an attractive intervention measure to mitigate Campylobacter in poultry. Our recent studies have demonstrated that the outer membrane proteins CmeC (an essential component of CmeABC multidrug efflux pump) and CfrA (ferric enterobactin receptor) are feasible candidates for immune intervention against Campylobacter. By targeting these two promising vaccine …

Population Dynamics Of The Louisiana Black Bear In The Upper Atchafalaya River Basin, Kaitlin Christine O'Connell

Masters Theses

The Louisiana black bear (Ursus americanus luteolus) is listed as Threatened under the Endangered Species Act as a result of habitat loss and human-related mortality. Two of the 3 sub-populations must be viable for delisting to occur. I collected hair samples from 2010 to 2012 in a DNA mark-recapture study to augment data collected from 2007 to 2009 in the Upper Atchafalaya River Basin (UARB) to estimate abundance (N), growth rate (λ), and apparent survival rates (φ) to ultimately be used in a population viability analysis. In addition, I evaluated the effects of the opening of the …

Environmental Constraints On Cyanomyophage Abundance In The Subtropical Pacific Ocean, Tiana Maria Pimentel

Masters Theses

Viruses are abundant in the world’s oceans and are thought to be important participants in marine biogeochemical cycling. Of these viruses, cyanophages are considered especially important because they infect and lyse cyanobacteria, which are some of the main primary producers in marine environments. Cyanophages are thought to influence the abundance and diversity of cyanobacterial populations and impart significant mortality, thereby affecting primary productivity and microbial community structure. Despite their ecological relevance, little is known about how environmental factors shape cyanophage abundance and diversity over large temporal and spatial scales. To address this gap in knowledge, seawater samples were collected during …

Manipulating Lipolysis To Reduce Fatness And Improve Carcass Composition In Commercial Broilers, Rodney Barnett Ray

Masters Theses

Betaine has been studied as an osmolyte and methyl group donor for many species. Recent studies have found that betaine is able to increase muscle mass and reduce adiposity in meat type broilers birds. In experiment one, eight-hundred Cobb 500 broiler chicks were supplemented with betaine at 0.6 g/kg and 1.2g/kg. Birds had access to feed and water for ad libitum consumption for forty-two, forty-four, and forty-nine days. Birds and feed were weighed weekly. Carcass parameters (dress weight, breast percentage, and leg percentage) were taken at slaughter on days forty- two and forty-nine. Blood was taken at day forty-four to …

Aqueous Extracts Of Hibiscus Sabdariffa As Antimicrobials In Foods, Kristen Liane Higginbotham

Masters Theses

Hibiscus sabdariffa L. is a tropical shrub species cultivated in multiple countries and is mainly produced for its red calyces that are used for a tea beverage. Aqueous, lyophilized extracts of Hibiscus were examined for their chemical composition and antimicrobial activity against Escherichia coli O157:H7, Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), and Listeria monocytogenes.

Lyophilized, dialyzed extracts of commercially aquired calyces were examined in microbiological medium and milk at various fat levels for antimicrobial activity against E. coli O157:H7 and S.aureus. Extracts were either filtered or autoclaved to sterilize and tested in microbiological medium. Autoclaved extracts were more effective …

Small Scale Population Structure Of Pityopsis Ruthii And P. Graminifolia Var. Latifolia, Sarah Lynn Boggess

Masters Theses

Pityopsis graminifolia var. latifolia (Michx.) Small var. latifolia (Fern.) or narrowleaf silkgrass is an herbaceous perennial native to the southeastern United States and northern Central America. Pityopsis ruthii (Small) Small is an endangered plant endemic to the Hiwassee and Ocoee Rivers in Polk County, Tennessee. Little is known about the genetic diversity and population structure of both Pityopsis species as well as the phylogenic relationships between the species. In this study, 16 microsatellite loci were used to assess genetic diversity and population structure of 261 individuals of P. ruthii (n=167) and P. graminifolia var. latifolia (n=76). Pityopsis ruthii is …

Plasmodium Suppresses T Cell Responses To Heterologous Infections By Impairing T Cell Activation, Chelsi Elizabeth White

Masters Theses

Malaria is a devastating disease caused by parasites of the genus Plasmodium. Plasmodium falciparum, which is responsible for most malaria related fatalities, suppresses host immune responses during heterologous coinfections or following vaccination. However the mechanisms responsible for this defect are not well defined. The mechanism and to what extent this immunosuppression is occurring was investigated. This study demonstrates that both dendritic cell and T cell activation are impaired following a Plasmodium infection, ultimately altering the adaptive T cell response to secondary infections. T cell suppression is evident early on following a secondary infection and continues throughout the peak of parasitemia. …

Identification Of Actin Cytoskeletal Protein Interactions With The Fission Yeast Scaffold, Mid1, Marian Testori

Masters Theses

Cancer is a disease of uncontrolled cell division. Cell division in eukaryotic cells occurs by the formation of a contractile ring, predominantly composed of filamentous actin (F-actin). During mitosis, actin filaments polymerize to form rings at the medial plane of the cell that constrict causing the cell membrane to pinch and divide. Proteins that regulate this process are essential because dysregulation can lead to uninhibited cell growth and division. In fission yeast, the protein Mid1 functions as a scaffold to recruit regulatory proteins required for actin filament formation and simultaneously anchors the contractile ring at the cell division site. The …

Activation Of Nucleotide Binding Oligomerization Domain Containing Protein 1 In 3t3-L1 Adipocytes: Effects On Adipocyte Differentiation And Lipolysis, Jaanki Shamb Purohit

Masters Theses

Obesity, defined as having excess adipose tissue, is associated with chronic inflammation. Adipose tissue is made up of many cell types, including preadipocytes and adipocytes. Both preadipocytes and adipocytes express pattern recognition receptors that play important roles in innate immunity. Two families of pattern recognition receptors that have been studied in adipose tissue are Toll-like receptors (TLRs) and NOD-like receptors (NLRs). Activation of TLR2 and TLR4 has been shown to lead to proinflammatory response in adipocytes, which is shown to suppress adipocyte differentiation and stimulate lipolysis, one of the major physiological functions of adipocytes. However, the effects of NOD activation …

Factors Influencing Diarrheal Pathogen Presence In Tubewells Of Bangladesh, Kati Anne Ayers

Masters Theses

Diarrheal disease pathogens remain a major concern in developing countries as rotavirus is the leading cause of hospitalization of young children worldwide. A recent study has shown shallow groundwater in rural Bangladesh to be contaminated with bacterial and viral pathogens, but found no correlation between rotavirus and any fecal indicator or environmental parameter during the monsoon season of July, 2009. The objectives of this thesis were to examine the non-relationship between pathogens and fecal indicators, as well as to improve the understanding of the seasonal transport of viral pathogens, especially rotavirus, in shallow, sandy aquifers of Bangladesh. This was achieved …

Characterization Of A Glycosyphosphatidylinositol Anchor Transamidase In Arabidopsis Thaliana And The Function Of Gpi Anchored Proteins In Stomatal Development, Mark Gerald Ronald Bundy

Masters Theses

In plants stomata play a vital role for survival by allowing the gas exchange of CO₂ [carbon dioxide] and water vapor to occur. A stoma is a central pore flanked by two kidney shaped guard cells and in wild type there is at least one pavement cell between each stoma. The ERECTA (ER) gene family consisting of ER, ERL1, ERL2 is involved in regulation of stomata development, where a triple mutant of er erl1 erl2 displays an increased stomata index and clusters of stomata that disobey the one cell spacing rule. To better understand the pathway of stomata development, …

Use Of Capacitance Sensors For Development Of Conservative Irrigation Regimes, Ethan Daniel Hagen

Masters Theses

Several experiments were conducted to further develop capacitance sensor-based automated irrigation systems. The first experiment tested whether the photosynthetic response to decreasing volumetric water content (VWC) differed among four species tested. A sigmoidal curve best described the relationship for all species (r² [r-squared]>0.86). The VWC that maintained maximum photosynthesis at 90% was selected as a potential conservative irrigation set point and values were not different between species, nor were 100% container capacity values. This indicates that a single set point is adequate to initiate irrigation and that a common upper threshold for VWC can be used for this …

The Effects Of A Moisture-Wicking Fabric Shirt On The Physiological Responses During Acute Exercise In The Heat, Kimberly Wigboldy

Masters Theses

The purpose of this study is to investigate the effects that a form fitted, moisture-wicking fabric shirt, promoted to have improved evaporative and ventilation properties, has on the thermoregulatory, physiological and perceptual response during moderate intensity exercise in the heat for an extended duration of exercise of 90 minutes. Ten healthy subjects (7 males, 3 females), completed two heat stress tests consisting of 20 minute seated rest in a neutral environment (24°C, 60% RH), 30 minute seated rest in a hot environment (33°C, 60% RH), and 90 minutes of exercise(50% V0_{2 peak}) on a magnetically-braked cycle ergometerin a …

Bioconfinement Of A Putatively Sterile Nicotiana Hybrid And Development Of Tools For Assessing Gene Flow, John Hollis Rice

Masters Theses

Production of transgenic crops in open field environments is an ongoing concern of due to the potential for gene flow. New transgenic crops, such as plant-made-pharmaceuticals may generate additional concerns about effects of adventitious transgenes. Use of a bioconfinement strategy may alleviate any consequences by preventing gene flow. The following chapters discuss previous and current research on gene flow, testing of a Nicotiana hybrid system for bioconfinement efficiency, and development of methods for transgene detection. The candidate ‘platform plant’ that was tested is a Nicotiana hybrid (Nicotiana tabacum ‘TN 90’ × Nicotiana glauca) previously identified to be sexually …

A Comparison Of Salmonella Enterica Serovars: Are Prevalence, Virulence And Responses To Environmental Conditions Serovar Or Strain Dependent?, Nan Zhang

Masters Theses

Salmonella are considered the leading cause of foodborne illnesses with frequent outbreaks in United States. While more than 2500 serovars have been identified, Salmonella Typhimurium and Salmonella Enteritidis are primarily responsible for most human infections while Salmonella Kentucky and Salmonella Heidelburg are currently the most prevalent serovars associated with poultry contamination. The relationship between virulence and prevalence is not fully understood, but may be a result of environmental stress exposure such as acid stress. In this research, organic acid (acetate) and inorganic acid (hydrogen chloride) were applied to 15 different serovars isolated from human infections or poultry. The growth curves …

Single-Nucleotide Polymorphisms Associated With Performance Traits In Beef Cattle Grazing Endophyte-Infected Tall Fescue, Bryan Christopher Bastin

Masters Theses

Tall fescue (Lolium arundinaceum Schreb.) is the most prevalent forage in the Midsouth United States due in part to the presence of the endophytic fungus Neotyphodium coenophialum. The fungus, while conferring hardiness to tall fescue, contributes to decreased production efficiency in cow-calf operations. A previous genome-wide association study was performed using the Illumina 50k bovine SNP chip. Twenty-four SNP were found to be associated (P < 0.05) with adjusted birth weight and adjusted 205-day weights of calves from 48 beef cows at Ames Plantation. The first objective was to validate each SNP by testing associations with several additional phenotypes. Custom Taqman genotyping assays (Applied Biosystems, Foster City, CA) were subsequently designed to genotype each SNP in beef cattle located at Tennessee Tech University (n = 654), to validate associations in a large, independent herd. The results yielded 15 associations that were significant (P < 0.05) with 6 phenotypes linked to those affected by fescue toxicosis. The second objective investigated the link between fescue toxicosis and the XK, Kell blood group complex subunit-related, member 4 …

Pelagic Larval Duration Links Life History Traits And Species Persistence In Darters (Percidae: Etheostomatinae), Morgan Jessica Douglas

Masters Theses

Pelagic larval duration (PLD) likely influences evolutionary processes including dispersal, genetic connectivity, and extinction in aquatic organisms. PLD has been well studied in marine systems, but very few freshwater species have been studied. Darters are a diverse group of freshwater North American fish with available information on the length of this stage from propagation efforts. There is surprising variation in the length of this stage ranging from 0 to 60 days. By compiling information from Conservations Fisheries, Inc. (Knoxville, TN) and the literature, we were able to make comparisons between the PLD of 23 species and other life history characteristics. …