Life Sciences Commons^™

Impact Of Switchgrass Bioenergy Feedstock Production On Soil Carbon Dioxide Flux And Below Ground Soil Organic Carbon Storage In East Tennessee, Leah Denise Soro

Masters Theses

Bioenergy production from switchgrass has shown promise in restoring degraded soils and helping to mitigate greenhouse gas (GHG) emissions. CO₂ loss and C-sequestration in soils are important topics for research to better understand the environmental impacts of bioenergy crops. The need for more thorough research of the carbon cycle in soils used for bioenergy production precipitated the primary interest of this study. The specific objectives of this study were 1) to measure SOC under switchgrass production in order to predict storage of carbon in soils based on previous cropping history, land management, soil physical characteristics, and time; and to …

Capture-Recapture Of White-Tailed Deer Using Dna Sampling From Fecal Pellet-Groups, Matthew James Goode

Masters Theses

Reliable density estimates of game and keystone species such as white-tailed deer (Odocoileus virginianus) are desirable to set proper management strategies and for evaluating those strategies over time. However, traditional methods for estimating white-tailed deer density have been inhibited by behavior, densely forested areas that can hamper observation (detection), and invalid techniques of estimating effective trapping area. We wanted to evaluate a noninvasive method of mark-recapture estimation using DNA extracted from fecal pellets as the individual marker and for gender determination, coupled with a spatial detection function to estimate density (Spatially Explicit Capture-Recapture, SECR). We collected pellet groups …

An Evaluation Of Population Estimators And Forage Availability And Nutritional Quality For White-Tailed Deer In Tennessee, Jared Tyler Beaver

Masters Theses

Given the white-tailed deer’s (Odocoileus virginianus; deer) popularity and potentially negative impact on forested systems; Arnold Air Force Base (AAFB) in Tullahoma, Tennessee, USA has made minimizing negative deer impacts on biodiversity a priority. To address these management issues, I initiated a study on AAFB to investigate deer survey techniques and the effects of deer density on forage availability across vegetative communities.

Current use of infrared-triggered cameras (camera) for estimating deer populations does not provide a measure of precision critical for density estimation. I conducted a camera survey for deer in Wildlife Management Area (WMA) Units 1 and …

Factors Related To Nest Survival And Over-Winter Survival Of A Northern Bobwhite (Colinus Virginianus) Population In Southwest Florida, Steven Kenneth Brinkley

Masters Theses

The northern bobwhite (Colinus virginianus) is a gallinaceous upland game bird dependent on early successional grassland habitat for reproduction and survival. Bobwhite populations have been declining range-wide for nearly a half century. The habitat of Babcock-Webb Wildlife Management Area (BWWMA) in southwest Florida is mostly virgin, early successional grassland and pine flatwoods. Although BWWMA is located in the far southern end of the bobwhite range, the area is a popular public land for bobwhite hunting. The BWWMA bobwhite population has declined evidenced by a dramatic decrease in harvest over the last 20 years. The two objectives of my …

Influence Of Timing Of Prescribed Burn On Native-Warm Season Grass Forage Quality In Tennessee, Amanda L. Mathenia

Masters Theses

Native warm-season grass stands have the prospective to provide nutritious summer forage in grazing systems. The study examined the influence of timing of prescribed burn on native warm-season grass stands in Tennessee. The purpose of the study was to determine the nutritional quality of forage as it relates to the timing of prescribed burns on native warm-season grass stands in Tennessee. The prescribed burns were conducted in March, April, May, and September. Forage samples were collected at Ames Plantation, West Tennessee Research and Education Center, Bridgestone/Firestone Wildlife Management Area, and Yuchi Wildlife Management Area. These samples were then analyzed for …

Consequences Of Gene Flow And Transgene Introgression In Hybrids Between Transgenic Brassica Napus And Its Weedy Wild Relative Brassica Rapa, Reginald Jason Millwood

Masters Theses

The adventitious presence of transgenes and their potential impact on the environment has been a topic of concern for many years. To address these concerns the following chapters discuss past and current research of gene flow and introgression, methods for transgene detection and monitoring, and the results from field-level experiments using artificially introgressed advanced generation hybrids. The field studies were designed to be a worst-case scenario where hybrids were produced by hand-crossing transgenic Brassica napus (AACC, 2n = 38) and its weedy wild relative Brassica rapa (AA, 2n = 20). B. napus was transgenic for the green fluorescent protein [m-GFP-5 …

Eat The Rainbow! An Evaluation Of A Short-Term Fruit And Vegetable Nutrition Education Intervention For Elementary School Children, Elizabeth Diane Miller

Masters Theses

Objective: To test differences on mean fruit and vegetable (FV) eaten, liking, preference, and self-efficacy scores among 3 modes of nutrition education intervention after a 3-week intervention.

Design: Convenience sample, pre- and post-test, quasi-experimental design.

Setting: Three elementary schools in a rural Eastern Tennessee County.

Participants: Participants were 160 3^rd-5^th graders.

Interventions: Three study schools: experiential (nutrition education, taste tests, and learning activity), conventional (nutrition education and learning activity), and control (learning activity).

Main Outcome Measures: Changes in pre- to post-intervention mean FV eaten, liking, preference, and self-efficacy scores.

Analysis: Mixed model ANOVA to compare the mean …

Assessing Mitochondrial Activity In Embryos From Heat-Stressed Ova, Kimberly Ann Nagle

Masters Theses

Elevated ambient temperatures negatively impacts pregnancy rates in agriculturally important females. An oocyte undergoing meiotic maturation exposed to a physiologically-relevant heat stress results in alterations of developmentally important processes and reportedly decreases subsequent developmental potential after fertilization. To address problems of reduced competence after exposure to heat stress for the first 12 h of meiotic maturation (hIVM), Payton (2009) assessed the transcriptome profiles of oocytes and associated cumulus cells by microarray analysis and reported heat-induced perturbations at the molecular level in the oocyte. Specifically, 20 transcripts involved in mitochondrial function exhibited alterations in relative abundance of heat-stressed oocytes …

Functional Characterization Of An Endoglucanase From Tribolium Castaneum (Tceg1) In Saccharomyces Cerevisiae And Characterization Of Cellulolytic Activity In The Digestive Fluids Of Thermobia Domestica (Zygentoma: Lepismatidae), Derek Mychel Shirley

Masters Theses

Cellulosic ethanol has the potential to be a significant biofuel due to its sustainability and high energy yield. However it is the recalcitrance of cellulose that presents a costly road block in the economic feasibility of cellulosic ethanol production. The enzymatic degradation of lignocellulosic biomass has the greatest potential for reducing the production costs of this process. While many commercially viable cellulases have been identified in bacteria and fungi, insects remain a relatively untapped source of these enzymes. In fact recent studies have shown that insects produce highly active endogenous cellulases capable of completely hydrolyzing cellulose to glucose, without the …

Physical And Chemical Stability Of Fish Oil-In-Water Emulsions Prepared With Preheated Wpi And Maltodextrins, Sutida Watthanapimol

Masters Theses

Fish oil has abundant polyunsaturated fatty acids that are important to health but are oxidized easily during shelf-life storage. Engineering oil/water interfaces of emulsions has been studied extensively, but practical technologies are still demanded by the food industry. Whey proteins aggregate during heating, and the preheated whey protein/aggregate may increase the robustness of interfaces and in turn improve oxidative and physical stability of fish oil emulsions. In this study, whey protein isolate (WPI) solutions were prepared at 0-100 mM NaCl and pH 7.0 and preheated at 85 °C for 5-30 min. The preheated WPI was used to prepare fish oil …

Bee Visitation To Crops And Other Flowers Planted As Bee Food, Michael Edward Wilson

Masters Theses

Farms that require insect pollination and reside in diverse landscapes benefit from pollination by native bees. However, populations of native bees and honey bees are generally in decline and this threatens food production. Documentation of crop pollination as an ecosystem service is needed to identify potential impacts from declining bee populations. This study identifies communities of bees providing pollination and how they vary across different crops and environmental conditions. Managing landscapes to provide additional food sources for bees may improve the health of wild and managed bees. This study also evaluated the attractiveness of bees to selected species of plants …

Integrated Strategies For Controlling Warm-Season Turfgrass Weeds, Matthew Thomas Elmore

Masters Theses

Herbicidal inhibitors of 4-hydroxyphenylpyruvate dioxygenase (HPPD) such as mesotrione, topramezone and tembotrione were evaluated in greenhouse experiments for activity against bermudagrass. While topramezone and tembotrione exhibited greater activity than mesotrione, none of these herbicides provided acceptable bermudagrass control. These herbicides reduced leaf tissue chlorophyll and carotenoid pigment concentrations in bermudagrass. Changes in turfgrass pigmentation were quantified using HPLC analogy as well as evaluations of visual bleaching and measurements of chlorophyll fluorescence yield (F_v/F_m). Results indicated that these more expeditious methods of evaluating HPPD-inhibiting herbicide activity (visual evaluations and F_v/F_m) cannot be used …

Development Of An Environmental Monitoring System For Greenhouse Disease Management, Crystal Marie Kelly

Masters Theses

A commercial African violet (Saintpaulia ionantha) grower experiences yield loss due to a leaf spot disease known as Corynespora casssiicola. Spotted leaves make the plants unmarketable. Outbreaks of the disease are costly and difficult to prevent. Greenhouse monitoring systems currently available on the commercial market do not have sufficient spatial or temporal resolution to be able to correlate the environmental conditions of the greenhouse with disease outbreaks. A new system was designed specifically to monitor for disease favorable conditions. The system developed for this project consists of several sensor stations and a coordinator station. The coordinator station …

Identifying Pathogens Of Switchgrass And Investigating Antimicrobial Activity Of Switchgrass-Derived Extractives, Andrea Linh Vu

Masters Theses

Switchgrass is an increasingly important biofuel crop, but knowledge of switchgrass fungal pathogens is not extensive. The purpose of this research was to identify the fungal pathogens that decrease crop yield of switchgrass grown in Tennessee and to investigate a potential value-added by-product of the switchgrass biofuel conversion process. The specific objectives were 1) to identify and characterize prevalent fungal pathogens of switchgrass in Tennessee, 2) assess switchgrass seed produced in the United States for seedborne fungal pathogens, and 3) evaluate switchgrass extractives for antimicrobial activity against plant pathogens.

Diseased switchgrass samples were collected from several locations in East Tennessee. …

Getting Heavy: An Exploration Into The Effects Of D2o And High Hydrostatic Pressure On R67 Dihydrofolate Reductase, Mary Jane Timson

Masters Theses

Chromosomal dihydrofolate reductase (DHFR) enzymatically reduces dihydrofolate (DHF) to tetrahydrofolate (THF) using NADPH as a cofactor. R67 DHFR is an R-plasmid encoded enzyme that confers resistance to trimethoprim (TMP), an antibacterial drug. It shares no structural homology with TMP targeted, chromosomal DHFRs.

Previous osmolyte studies in our lab have indicated that DHF binding to R67 DHFR is accompanied by water uptake and NADPH binding is accompanied by water release. These data suggest that water plays a role in balancing the binding affinity. This may happen as R67 DHFR has a generalized binding surface and may need differential water effects to …

Evaluation Of An Intensive Data Collection System For Tennessee Surface Water Quality Assessment And Watershed Model Calibration, Hannah Marie Armstrong

Masters Theses

Water quality regulators, such as the Tennessee Department of Environment and Conservation, are challenged by data scarcity when identifying surface water quality impairment causes and pollutant sources. Surface water quality model users also seek to identify pollutant sources and design and place best management practices to efficiently improve water quality, but have insufficient data for model calibration. This research documents the design and evaluation of a novel, intensive water quality data collection system consisting of a automatic sampler, bi-weekly grab sampling, and a long term deployment sonde. System design characteristics that were emphasized included a focus on gathering data for …

Functional Analysis Of The Cyp6a8 Gene Promoter Of Drosophila Melanogaster For Caffeine- And Phenobarbital-Inducibility By Site-Directed Mutagenesis, Olivia Nichole Hill

Masters Theses

Cytochrome P450 enzymes (CYPs), found in almost all organisms, are involved in endobiotic metabolism and detoxification of xenobiotic compounds, such as drugs, pollutants, and insecticides. In insects, CYPs play a major role in conferring resistance to various insecticides including DDT. In Drosophila and other insects, DDT-resistant strains exhibit increased expression of multiple P450 genes; however, the mechanism of overexpression is unknown. Since many CYP genes including Cyp6a8 of Drosophila are induced by caffeine and other xenobiotics, these chemicals are used as tools to understand the regulation of these genes. Previously it was shown that the 0.8-kb (-1/-732) and 0.2-kb (-1/-170) …

Non-Thermal Plasma Inactivation Of Bacillus Amyloliquefaciens Spores, Yaohua Huang

Masters Theses

Bacterial spores have remarkable resistance to a variety of harsh conditions, causing spoilage in food industry and becoming the primary bacterial agent in biowarfare and bioterrorism. In this study, inactivation mechanisms of Bacillus amyloliquefaciens (BA) spores by non-thermal plasma (NTP) were investigated by using Fourier-transform infrared spectroscopy (FTIR) as a major tool to exam spores after NTP treatment. Chemometric techniques, such as multivariate classification models based on soft independent modeling of Class Analogy (SIMCA) and Principal Component Analysis (PCA), were employed to identify functional group changes in FTIR spectra. The IR absorbance bands correlated to dipicolinic acid (DPA) decreased after …

Effects Of Different Silvicultural Practices On Wild Turkey Brood Habitat And Regeneration In Upland Hardwoods, John Michael Mccord

Masters Theses

Optimum brood cover for wild turkeys is composed of herbaceous cover <0.5 m tall that conceals poults from predators and allows travel underneath. On tracts of hardwoods where early succession stages and young forest cover are scarce, a lack of understory development can limit turkey populations. Additionally, retaining oak on these sites after logging or habitat enhancement is important to provide future timber value and hard mast. I compared the effects of silvicultural practices (multiple fires [F], shelterwood cutting [S], shelterwood cutting with one fire [SF], retention cutting [R], retention cutting with multiple fires [RF], retention cutting with herbicide application [RH], and retention cutting with herbicide application and multiple fires [RHF]) with controls (C) on wild turkey brood habitat and oak regeneration in upland central hardwood stands. I measured structure and food resources to quantify the quality of wild turkey brood cover. Shelterwood and retention cuts increased photosynthetically active radiation. However, herbaceous, vine, and bramble groundcover did not increase. Woody regeneration was greater following canopy reduction and understory disturbance compared to C. Disturbance (fire or herbicide) was required to maintain vegetation at the ideal height for wild turkey broods. Soft mast production increased after canopy reduction with and without fire. Invertebrate biomass did not increase following any treatment, but availability exceeded the dietary requirements of a wild turkey brood. I also counted stem density of oak and competitor regeneration in response to these treatments. Seedlings <12.7 cm were ephemeral. S and SF had a greater density of oak stems >1.4 m than C and F. However, S and SF also had the greatest density of oak >1.4 m prior to treatment. Canopy reduction increased oak competitors, but prescribed fire reduced competitors. I recommend canopy reduction, followed by repeated low-intensity prescribed fire to maintain low groundcover to enhance brood habitat for wild turkeys in mature closed-canopy upland hardwood stands.

Enhancement Of The Antimicrobial Activity Of Eugenol And Carvacrol Against Escherichia Coli O157:H7 By Lecithin In Microbiological Media And Food, Songsong Li

Masters Theses

Essential oils (EOs) or their isolated components, such as eugenol and carvacrol, have strong antimicrobial activities against both Gram-positive and Gram-negative bacteria and are generally recognized as safe by the FDA. However their hydrophobic properties limit their dispersion and stabilization in aqueous food systems. This requires higher concentrations, which in turn negatively affect the quality of foods. The objective here was to determine the effect of the natural emulsifier lecithin on the antimicrobial activity of eugenol and carvacrol and possible food applications. Escherichia coli K12 and E. coli O157:H7 strains ‘Cider’ and ATCC 43889 were used. Homogenized eugenol and carvacrol, …

Potential For Alternative Agricultural Enterprises To Replace Tobacco: Burley Producers Perceptions, Maria Paula Mendieta Umana

Masters Theses

Demand for domestic tobacco has decreased over the past two decades. In 2004, the tobacco buyout program terminated marketing quotas and price support established under the federal tobacco program in 1938. Additionally, in 2003, the World Health Organization Framework Convention on Tobacco Control (WTO FCTC) acknowledged the importance of supply control in conjunction with demand control strategies to eliminate or reduce the consumption of tobacco products. According to the Census of Agriculture, the number of tobacco farms in the US fell by 40 percent between 2002 and 2007. Tobacco farmers are looking for alternative on-farm and off-farm sources of income. …

Knowledge And Perceptions Of Agriculture In Tennessee Through Fall Agritourism Experiences, Jessica Jarrell Poore

Masters Theses

The purpose of this study was to identify the key educational components of agritourism in Tennessee. The study strived to identify if knowledge of the agricultural industry increased due to agritourism experiences and if perception of the agriculture industry changed due to the experience. Additionally, the research sought to describe visitor demographics and characteristics.Following a pilot study in 2009, three agritourism venues throughout the state of Tennessee were used to collect surveys to create a pool of respondents and to identify their original knowledge of perceptions of the agriculture industry for the 2010 study. Additional data was gathered through an …

Nuclear Receptors In Ecdysone-Mediated Programmed Cell Death In Drosophila Melanogaster, Ritika Sehgal

Masters Theses

The steroid hormone ecdysone plays vital roles during Drosophila development. Pulses of 20E during Drosophila life cycle function as temporal cues, signaling the onset of metamorphic processes, including the stage specific programmed cell death of larval tissues. Ecdysone is the critical developmental cue orchestrating the metamorphic reformation of CNS, resulting in the formation of adult-specific neural circuitry. Ecdysone signaling is transduced by a heterodimeric receptor complex formed between two nuclear receptors: EcR and Ultraspiracle (USP). There are 18 nuclear receptors known in Drosophila and EcR is the only receptor whose functions in neuronal PCD have been well recognized. Therefore, the …

Examining The Roles Of Pstoc75 Potra Domains In Chloroplast Protein Import, Richard Franklin Simmerman

Masters Theses

During chloroplast formation via endosymbiosis most of the plastid genome was transferred to the host nuclear genome. Genomic and proteomic analysis suggests that >95% of the original plastid proteome is now encoded in the nucleus, and these now cytosolically fabricated proteins require a post-translational transport pathway back into the organelle. This process is not well understood, yet it has been shown to involve translocons at the outer and inner envelope of the chloroplast membranes (TOC & TIC). These translocons interact with a cleavable N-terminal extension of between 20 and 100 residues on chloroplast-bound precursor proteins known as the transit-peptide. Precursor …

Bringing Biodiversity To Development: Perceptions Of Integrating Eucalyptus And Forest-Corridors Around The Serra Do Brigadeiro, Brazil, Maggie R Stevens

Masters Theses

The Atlantic Forest of south-eastern Brazil is a hot-spot for biodiversity and should be conserved. It is also at the center of the largest municipalities in Brazil and therefore has a severely fragmented landscape. Iracambi, a working farm near the Serra do Brigadeiro state park in Minas Gerais, is working for conservation in an area of intense agricultural production and expanding forestry industry. Most households in this rural area have some amount of eucalyptus on their property and consequently the director of Iracambi is developing the preliminary foundation for a forest corridor program comprised of primarily eucalyptus with the goal …

Intellectual Property And Policy Issues In Biotechnology, Amy Iver Yancey

Masters Theses

Intellectual property, particularly patents, plays a major role in innovation and discovery in biotechnology. Likewise, since the passage of the Bayh-Dole Act in 1981, patents have become an increasingly important factor in U.S. university-driven basic research, especially in the life sciences where patented technologies have transformed agriculture. Specifically, this paper looks at the potential impacts of these trends on university driven research, the university researcher, the pharmaceutical industry, and the farm sector with an emphasis on recent and pending court cases and legislation. This paper examines policy and adoptions issues in biotechnology and biomedicine in depth and touches on important …

High And Low Active Transit Accessibility On Greenways: The Relationship With Physical Activity, Dana Lizbeth Wolff

Masters Theses

Greenways (GW) can be sited to increase the potential for individuals to access the GW through active transit (AT) and provide opportunities for individuals to meet PA guidelines. PURPOSE: To determine if GWs, with varying AT access potential, relate to user characteristics and their GW-related PA. METHODS: A trail intercept survey measuring access mode, GW-specific PA, and demographics of GW users was administered to 611 adults on 2 GWs with high and low AT potential (GW_high vs. GW_low). RESULTS: Users of GW_high(N=216) compared to GW_low (N=400) were more likely to be younger, male, never …

Establishment And Persistence Of Legumes In Switchgrass Biomass And Forage/Biomass Production Systems, Kara Spivey Warwick

Masters Theses

Switchgrass, Panicum virgatum, is being developed as an economically and ecologically sustainable biomass crop. Nitrogen is considered one of the most limiting inputs of switchgrass. Alternatives to synthetic nitrogen fertilization may be nitrogen-fixing legumes interseeded into switchgrass. The objectives of this research were: (1) develop efficient legume management strategies for switchgrass production systems, (2) evaluate and identify cool and warm-season legumes that can be grown compatibly with switchgrass, (3) determine whether switchgrass yields are increased by legume N-fixation, and (4) determine N-fixation of common (Vicia sativa) and hairy vetch (Vicia villosa).

This study examined the …

Evaluation Of Capital Investment And Cash Flows For Alternative Switchgrass Feedstock Supply Chain Configurations, Jie Chen

Masters Theses

Biofuels have been widely recognized as a potential renewable energy source, and the United States’ government has been interested in producing ethanol from lignocellulosic biomass such as switchgrass. To evaluate whether lignocellulosic biomass based biofuels production is economically feasible, this paper estimated the capital investment outlays, operation costs, and net present value for investment in alternative switchgrass feedstock supply chain configurations in East Tennessee a 25 million gallon per year ethanol biorefinery. Two scenarios are analyzed in the study. The conventional hay harvest scenario includes the production, harvest, storage and transportation of biomass feedstocks from the fields to the biorefinery. …

Nutritional Ergogenic Aids: The Influences Of Carbohydrate-Protein Supplementation During Endurance Exercise, Adriana Marina Coletta

Masters Theses

Mixed results, in terms of performance benefits, have been found when comparing carbohydrate (CHO) and carbohydrate-protein (CHO-P) supplementation during endurance exercise. Thus this study assessed performance from three different supplements (CHO-P, CHO, double carbohydrate [CHO-CHO]) as compared to a placebo (PLA) during a time trial (TT) run. Twelve male recreational runners (age = 32.4 ± 9.5 yrs; body mass index [BMI] = 22.7 ± 1.5 kg/m2; VO2max = 59.68 ± 7.53 mL/kg body weight; 100% white) individually completed four, 12-mile TT runs, 7-10 days apart, at about 75% of the their race pace. Dietary and physical activity consistency within the …