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Evaluation Of The Over-Expression Of A Miscanthus X Giganteus Ppdk (C4ppdk1) In Switchgrass (Panicum Virgatum) For Improved Cold Temperature C4 Photosynthesis, Mathew Christian Halter

Masters Theses

Switchgrass (Panicum virgatum) has been proposed as a potential biofuel feedstock to aid in the displacement of petroleum-based combustible fuels over the course of the next several decades. Improving the yield potential of this perennial grass is therefore of economic interest. Increased net ethanol yields can be achieved in cellulosic feedstocks via two means: 1. Improved sugar release from digestible cell wall materials, 2. Increased overall biomass yield. The latter is the subject of this study.

As a C4 photosynthetic plant, switchgrass is highly productive in the hot, humid climate of the southeastern United States. By bypassing the …

The Seasonality Of Two Parasitoids (Spathius Agrili And Tetrastichus Planipennisi) Of The Emerald Ash Borer, Agrilus Planipennis, And A Survey For Native Natural Enemies Of The Emerald Ash Borer In Eastern Tennessee, Nicholas Andrew Hooie

Masters Theses

The emerald ash borer (EAB), Agrilus planipennisi Fairmaire (Coleoptera: Buprestidae), is an invasive species of bark borer native to eastern Asia whose primary habitat and food sources are trees in the genus Fraxinus. EAB is a major pest of all North American Fraxinus species and is responsible for mortality of millions of trees across its current North American range of 23 U.S states and 2 Canadian providences. After the discovery of EAB in Tennessee in 2010, parasitoid releases were started under the national EAB Biological Control Program. A research project was initiated in 2012 to 1) study the seasonality …

Relationships Of Temperament, Endocrine, Reproductive, And Behavioral Parameters Measured During Performance Testing Of Bulls, Sierra Ashley Lockwood

Masters Theses

The aim of this study was to examine relationships between bull temperament, behavior, growth, endocrine, and reproductive parameters measured over an 84 d test period. Bulls (n = 65) were reared in 6 pens separated on BW and age. Pen scores were assigned on d -1, 27, 55 and 83. On d 0, 28, 56, and 84, exit velocity, BW, time it took each bull to leave the chute, bull order through chute, and hair and blood samples were recorded or collected. Frame score was calculated, carcass ultrasounds and breeding soundness exams were performed on d 84. ADG was calculated …

Linking Dna Polymorphisms And Populations' Evolutionary History, Ivan Juric

Doctoral Dissertations

This dissertation seeks to provide an understanding of how different evolutionary forces can affect the DNA polymorphism patterns. I use a combination of individual-based simulations and analytical to examine polymorphism patterns during divergence with gene flow, hybridization and territory expansion. In the first chapter, I show how during divergence with gene flow the appearance and maintenance of “Genomic Islands of Divergence” can be explained using standard population genetics terminology, thus removing some of the confusion recently introduced in that literature. In the second chapter I derive the expressions for the distribution of coalescent times and pairwise differences in a hybridization …

Role Of Leucine In Modulation Of Mitochondrial Biogenesis And Sirt1-Ampk Signaling In C2c12 Myotubes, Chunzi Liang

Doctoral Dissertations

Mitochondrial dysfunction in skeletal muscle has been considered as a crucial step in the development of metabolic diseases, including insulin resistance syndrome, type 2 diabetes and cardiovascular diseases. Previous studies have demonstrated that dietary branched-chain amino acids, particularly leucine, protects against high-fat diet induced impairment of mitochondria and insulin resistance in skeletal muscle and adipose tissue through mTOR-dependent and independent pathways. In addition, previous ex vivo and in vitro approaches from this laboratory indicate that leucine and its metabolites (HMB and KIC) stimulate mitochondrial biogenesis and promote energy partitioning from adipocytes to muscle cells, partially through SIRT1 signaling. Moreover, recent …

World Wide Diversity Of Phytophthora Capsici, Dylan B. Storey

Doctoral Dissertations

The plant pathogen Phytophthora capsici is a genetically diverse organism that is a global problem. It effects many crops across the Solanacea, Cucurbitacea, andLeguminosea. As a result of the large diversity between individuals (and by extension populations) it has been previously near impossible to make meaningful comparisons between individuals of geographically distinct locations. Here we present the results of applying Next Generation Sequencing (NGS) technologies to a representative panel of isolates. This information and data is further used to demonstrate how this diversity has a functionally relevent effect on a class of proteins responsible for the infectious process. We …

Behavioral Responses Of Brazilian Free-Tailed Bats (Tadarida Brasiliensis) To Noctuid Moth Migrations, Jennifer Joy Krauel

Doctoral Dissertations

Animal migrations involve significant movement of biomass across landscapes and are likely to have cascading effects on animal and plant communities. However, most studies on migration address the behavior and ecology of single taxa, such as birds or insects. Few consider more than one trophic level or predator/prey interaction within the overall migration context. I studied the migration ecology of noctuid moths and of Brazilian free-tailed bats in Texas. Noctuid moth migrations during the 2010-2012 fall seasons were driven significantly by weather at the regional and local levels. Bats also responded to the same weather patterns, with changes in body …

Feeding State, Vitamin A Status And Atypical Protein Kinase C Modulate The Insulin-Regulated Gene Expression In Rat Hepatocytes, Wei Chen

Doctoral Dissertations

Hormonal and nutritional stimuli coordinately regulate the glucose and lipid metabolism in the liver. Dysregulated hormonal balance and nutrient metabolism not only disrupt the energy homeostasis, but also predispose individuals to the development of obesity and its related metabolic diseases. Research presented in this dissertation investigated the effects of a nutritional factor, vitamin A (VA), and a potential component of insulin signaling cascade, atypical protein kinase C (aPKC), on the glucose and lipid metabolic genes transcription in primary hepatocytes from Zucker lean (ZL) and fatty (ZF) rats.

To examine VA effects, we put ZL and ZF rats with different VA …

Impacts Of Climate Change, Human Land Use, And Mercury Contamination On Southern Appalachian Plethodontid Salamanders, Michael Kevin Hamed

Doctoral Dissertations

The Southern Appalachian Mountains are home to the greatest diversity of Plethodontid Salamanders in the world. The future for these salamanders is uncertain as globally amphibians have been experiencing significant population declines. We investigated the impact of habitat loss, chemical contaminants, and climate change on Plethodontid salamanders in northeastern Tennessee and southwestern Virginia. Four-toed salamanders (Hemidactylium scutatum) were negatively impacted by powerline right-of-way (ROW) mowing. Embryonic and larval survival significantly decreased in ROW after mowing and required up to 3 years of vegetation regrowth to reach post mowing survival. We also investigated mercury contamination in black-bellied salamanders ( …

Casein Micelles And Their Properties: Polydispersity, Association With Vitamin A And Effect Of Ultra-High Pressure Homogenization, Maneesha Sheenu Mohan

Doctoral Dissertations

The internal structure of casein micelles is not fully understood. In the present work, we explore some of the basic questions about casein micelles in bovine milk including its size distribution, native binding properties and effect of ultra-high pressure homogenization (ultra-HPH) on technological properties of casein micelles. The size distribution of casein micelles was studied by cryo-TEM using skim milk from four cows. The degree of variation in casein micelle sizes (polydispersity) ranged between 0.39 and 0.47 for a size distribution ranging from 10 to 693 nm. These results indicated high polydispersity of casein micelles in milk from single cows. …

Systems Biology Of Microcystis Blooms, Morgan Michelle Steffen

Doctoral Dissertations

Cyanobacterial harmful algal blooms (cHABs) degrade freshwater lakes worldwide. Accumulation of nuisance biomass and production of noxious secondary metabolites can result in an expansive impact on both lake ecology and the surrounding communities. The cHAB forming organism Microcystis aeruginosa is known to produce the toxin microcystin, a compound nicknamed “fast death factor,” which has been implicated in animal poisonings and human liver failure and cancers. M. aeruginosa inhabits a wide range of freshwater lakes around the world, such as Lake Erie (USA/Canada) and Lake Tai (Taihu, China), and is often a dominant member of bloom communities. Such systems are well-studied …

Fabrication Of Zein Nanoparticle-Biopolymer Complexes To Deliver Essential Oils In Aqueous Dispersions, Huaiqiong Chen

Doctoral Dissertations

Zein, alcohol-soluble corn proteins, easily precipitate as nanoparticles after dispersing a stock zein solution with a polar solvent into water. The process can be used to nanoencapsulate essential oils (EOs). However, the stability of hydrophobic zein nanoparticles is a challenge for their application in aqueous food systems. The goal of this dissertation reseach was to stabilize zein nanoparticles in aqueous dispersions by forming complexes with water-soluble biopolymers. The stabilization of zein nanoparticles was first studied using sodium caseinate by dispersing hot 50% aqueous ethanol solution with both polymers in water. The nanoparticles contained κ-casein and zein, and the spray-dried nanoparticles …

The Economic Costs And Ecological Benefits Of Protected Areas For Biodiversity Conservation, Gwenllian D. Iacona

Doctoral Dissertations

Conservation science acknowledges that economic cost and ecological benefit information is important for effective biodiversity conservation decision making. Obtaining this information for protected areas has proven difficult, however. This dissertation explores various aspects of obtaining information on the costs and benefits of protected areas in an effort to support applied conservation. Here I present a set of studies that 1) examine the threat and cost of plant invasion on protected areas, both for cumulative invasion and 2) across species that differ in their management priority, 3) provide a method for measuring the benefit of forest conservation, and 4) describe the …

Alternative Strategies For Weed Control In Creeping Bentgrass, Matthew Thomas Elmore

Doctoral Dissertations

Creeping bentgrass (CBG) (Agrostis stolonifera L.) is the most widely used cool-season turfgrass species on golf course fairways and tees in the United States, but it is tolerant of few post-emergence herbicides. Commercial herbicide development is currently focused on providing superintendents with herbicides that pose minimal environmental impact and can be used effectively at lower application rates than older alternatives. However, few of these products are safe for use on CBG. Several projects were conducted to evaluate alternative strategies to increase CBG herbicide tolerance.

Plants naturally contain enzymatic systems that metabolize xenobiotics. The interspecies variability in these enzymes is …

The Effects Of Leucine And Dairy Products On Adipose Tissue Inflammation: The Role Of Adipocyte Derived Microvesicles, Benjamin Jones Curry

Doctoral Dissertations

Obesity is characterized by chronic oxidative and inflammatory stress, and adipose tissue is a significant source of inflammatory cytokines. Previous studies demonstrated that dairy products (rich in calcium and leucine) can alleviate obesity-associated inflammatory stress through suppression of 1, 25-dihydroxycholecalciferol (calcitriol) with calcium and the high leucine content in dairy. We have also shown leucine treatment increases anti-inflammatory adiponectin expression and decreases pro-inflammatory cytokines TNF-a [alpha], MCP-1, and IL-6 expression in adipocytes. Therefore, we sought to determine if these alterations in inflammatory cytokine production could have a functional effect on the inflammatory process, specifically monocyte – endothelial cell adhesion as …

Population Dynamics And Genetic Structure Of Louisiana Black Bears In The Lower Mississippi Alluvial Valley Of Louisiana, Jared Scott Laufenberg

Doctoral Dissertations

In 1992, the U.S. Fish and Wildlife Service granted the Louisiana black bear threatened status under the U.S. Endangered Species Act, listing loss and fragmentation of habitat as the primary threats. The 1995 Recovery Plan outlines recovery goals designed to meet the objective of reducing threats to the Louisiana black bear metapopulation and supporting habitat. To meet that objective, the Recovery Plan requires 1) at least 2 viable subpopulations, 1 each in the Tensas and Atchafalaya River Basins, 2) movement corridors between the 2 viable subpopulations, and 3) long-term protection of the habitat supporting each viable subpopulation and interconnecting corridors …

Comparative Proteomics Reveals Core Vs. Unique Molecular Signatures For Dissimilatory Metal Reducing Bacteria Grown With Various Electron Acceptors, Xiaoxin Liu

Doctoral Dissertations

Dissimilatory metal reducing bacteria (DMRB) are probably one of the most respiratory versatile microorganisms on earth. Their ability to use metals as terminal electron acceptor allows them to survive in severe environments (e.g. radionuclide contaminated soil). In addition to metals, many other organic and inorganic substrates can be utilized as electron acceptors for DMRB respiration, including fumarate, nitrate, oxygen, etc. Genome information for many DMRB species is available, which reveals large numbers of c-type cytochrome encoding genes present in their genomes. For example, the genomes of three DMRBs, Anaeromyxobacter dehalogenans strain 2CP-C, Shewanella oneidensis strain MR-1, and Geobacter daltonii …

Applications And Improvements In The Molecular Modeling Of Protein And Ligand Interactions, Jason Bret Harris

Doctoral Dissertations

Understanding protein and ligand interactions is fundamental to treat disease and avoid toxicity in biological organisms. Molecular modeling is a helpful but imperfect tool used in computer-aided toxicology and drug discovery. In this work, molecular docking and structural informatics have been integrated with other modeling methods and physical experiments to better understand and improve predictions for protein and ligand interactions. Results presented as part of this research include:

1.) an application of single-protein docking for an intermediate state structure, specifically, modeling an intermediate state structure of alpha-1-antitrypsin and using the resulting model to virtually screen for chemical inhibitors that can …

Relationships Among Prochlorococcus Ecotypes Across Oceanic Temperature Ranges, Jeremy Werner Chandler

Doctoral Dissertations

Prochlorococcus, the world’s smallest known photosynthetic organism, is an open ocean cyanobacterium, thought to be globally significant in nutrient cycling. Genetically and physiologically distinct “ecotypes” of Prochlorococcus populate the world’s subtropical and tropical oceans. A few of these key ecotypes comprise the majority of these populations, with the dominant ecotypes frequently varying as a function of depth and latitude. The mechanisms underlying the specific distributions of the ecotypes remain poorly understood, but temperature was believed to play a key role in latitudinal partitioning. Quantitative PCR (Q-PCR) was used to assess ecotypic abundances across transects spanning the Pacific Ocean from 27°N …

New Remote Sensing Methods For Detecting And Quantifying Forest Disturbance And Regeneration In The Eastern United States, Michael Joseph Hughes

Doctoral Dissertations

Forest disturbances, such as wildfires, the southern pine beetle, and the hemlock woolly adelgid, affect millions of hectares of forest in North America with significant implications for forest health and management. This dissertation presents new methods to quantify and monitor disturbance through time in the forests of the eastern United States using remotely sensed imagery from the Landsat family of satellites, detect clouds and cloud-shadow in imagery, generate composite images from the clear-sky regions of multiple images acquired at different times, delineate the extents of disturbance events, identify the years in which they occur, and label those events with an …

Structure, Function And Regulation Of Two Isoforms Of Glutamine Synthetase From Soybean Root Nodules, Pintu Daulatrao Masalkar

Doctoral Dissertations

Glutamine synthetase (GS) is a major ammonia assimilatory enzyme in soybean nodules. The four isoforms of cytosolic glutamine synthetase (GS₁[glutamine synthetase 1]β[beta]1, GS₁β2, GS₁γ[gamma]1 and GS₁γ2) present in soybean nodules are 80% identical with respect to amino acid sequence, and share similar kinetic properties. It is shown all major GS₁ isoforms interact with nodulin 26, a member of the aquaporin family of membrane channels. Nodulin 26 is the major protein component of the symbiosome membrane (SM), where it serves a function as an ammonia and water channel. The site of interaction …

Development Of An Experimental And Computational Platform For Enhanced Characterization Of Modified Peptides And Proteins In Environmental Proteomics, Ritin Sharma

Doctoral Dissertations

Over the last decade, mass spectrometry based proteomics has been established as the front-runner in systems-level protein expression studies. However, with the field progressing into research of more and more complex samples, novel challenges have been raised with respect to efficient protein extraction and computational matching. In this dissertation, various aspects in the proteomics workflow, including experimental and computational approaches, have been developed, optimized and systematically evaluated. In this work, some of the critical factors with respect to proteomics sample preparation, like available biomass, detergent removal methods, and intact protein fractionation to achieve deeper proteome measurements were evaluated. The presented …

Quantitative Characterization Of Proteins And Post-Translational Modifications In Complex Proteomes Using High-Resolution Mass Spectrometry-Based Proteomics, Zhou Li

Doctoral Dissertations

Mass spectrometry-based proteomics is focused on identifying the entire suite of proteins and their post-translational modifications (PTMs) in a cell, organism, or community. In particular, quantitative proteomics measures abundance changes of thousands of proteins among multiple samples and provides network-level insight into how biological systems respond to environmental perturbations. Various quantitative proteomics methods have been developed, including label-free, metabolic labeling, and isobaric chemical labeling. This dissertation starts with systematic comparison of these three methods, and shows that isobaric chemical labeling provides accurate, precise, and reproducible quantification for thousands of proteins. Based on these results, we applied this approach to characterizing …

Active Families In The Great Outdoors: A Family-Centered Program To Increase Physical Activity Levels, Perceptions, And Behaviors, Jennifer Irene Flynn

Doctoral Dissertations

Physical activity levels of adults and children are low, and the amount of time children spend being active outdoors is decreasing. Parents play a critical role in developing health behaviors of children and ways to increase physical activity and encourage an active family culture are needed. Promotion of family outdoor physical activity, which includes at least one parent and one child from a home engaging in physical activity together, is understudied. Therefore, the purpose of this dissertation was to 1) describe the type, frequency, and duration of family physical activity, 2) determine whether changes in the duration and number of …

Biogeographical Patterns, Ecological Drivers, And Evolutionary Mechanisms Of Plant Invasions, Rafael Dudeque Zenni

Doctoral Dissertations

Understanding and predicting organisms’ responses to novel environments is a key issue for global change biology. In this dissertation, I study biogeographical patterns of plant invasions in Brazil, explore some of their ecological drivers, and disentangle the gene-level mechanisms that cause introduced organisms to become successful or failed invaders. I found that, for the invasive flora of Brazil, species were not introduced to new regions at random and that a species’ reason for introduction and continent of origin were associated. Asian ornamental and African forage plants are overrepresented, and two families (Poaceae and Fabaceae) dominate the invasive flora of Brazil. …

Transfer And Survival Of Microorganisms To Produce From Surface Irrigation Water, Stuart Jamison Gorman

Masters Theses

Surface water irrigation sources are widely used for fruit and vegetable crop production in the United States. Surface water is inherently prone to direct and indirect contamination with animal fecal material. Hence, the microbial quality of surface water sources can be highly variable. Water used for irrigation is considered a common source for produce contamination. In addition to this, fruits and vegetables are commonly consumed fresh or minimally processed, thus emphasizing the need for preventative measures in production of fresh produce. This study will examine transfer from naturally contaminated irrigation water to cantaloupes using drip and overhead spray irrigation methods. …

Assessment Of Smallmouth Bass Micropterus Dolomieu And Rock Bass Ambloplites Rupestris Growth And Condition In The Little River, Tennessee, Justin Robert Wolbert

Masters Theses

The Little River in Blount County, Tennessee, is a popular tourist location and fishery. It originates inside the Great Smoky Mountains National Park (GSMNP) and has sustained few impacts due to the protection of the Park. Growth and condition of smallmouth bass Micropterus dolomieu and rock bass Ambloplites rupestris were evaluated in Little River, Tennessee, from April to August 2013 and related to populations from other rivers in East Tennessee. Samples were collected via boat and backpack electrofishing. Selective sampling techniques targeting five or more fish in each 25.4- mm class produced 97 smallmouth bass and 48 rock bass. Otoliths …

Physical Activity In Individuals With Down Syndrome, Chelsea B. Spurgeon

Chancellor’s Honors Program Projects

No abstract provided.

Effects Of Different Approach Directions And Sizes Of Selected Tennis Forehand Strokes On Knee Biomechanics, Louise Barbara Beggs

Masters Theses

Tennis is a global sport and knee injuries are prevalent, ranging from acute to chronic and minor, to severe. Different directional movements and speeds involved in tennis may lead to a higher chance of injury due to changing loading rates at the knee. This study investigates effects of diagonal and lateral forehand strokes with step or lunge on kinematics and kinetics of the knee on the dominant leg during simulated tennis play. Ten National Tennis Ranking Program (NTRP) players level 4.0 upwards were recruited for the study. A motion analysis system was used to obtain three-dimensional joint kinematics, and force …

Carbon Sequestration, Carbon Markets, Technical Efficiency And Maize Production Using Conservation Agriculture In Mozambique, Timoteo Eduardo Simone

Masters Theses

Conservation agriculture practices are a promising sustainable farming system being promoted by various organizations in Mozambique. This thesis analyzes the impact of adoption of conservation agriculture practices on maize production technical efficiency, carbon sequestration and farmer income. The technical efficiency estimation utilizes data from a household survey conducted in Manica and Tete provinces of Mozambique. Soil carbon simulations use information from various sources including the household survey, European Energy markets and local meteorological data from the National Oceanic and Atmospheric Administration.

The second chapter of the thesis evaluates the technical efficiency of maize production using conservation agriculture practices. This section …