Life Sciences Commons^™

Effects Of Synthetic Turf And Shockpads On Impact Attenuation Related Biomechanics During Drop Landing, Hang Qu

Masters Theses

Synthetic turf has been widely utilized in sports since 1964. Discrepancies, however, in injury incidence on synthetic turf and natural grass have been reported throughout studies. Adding a shock pad under synthetic turf carpet is claimed to aid in energy absorption and decrease impact loading. Although some studies have conducted materials tests and compared mechanical characteristics of synthetic turf with different shock pads, no studies have examined biomechanical characteristics of impact related human movements on an infilled synthetic turf system with different underlying shock pads. The purpose of this research was to investigate effects of an infilled synthetic turf with …

Switchgrass Extractives Have Potential As A Value-Added Antimicrobial Against Plant Pathogens And Foodborne Pathogens, Alexander Ian Bruce

Masters Theses

Panicum virgatum (switchgrass), a perennial grass native to North America, is a leading biomass feedstock candidate for the manufacture of cellulosic ethanol. Switchgrass is considered a viable option for biofuel production due to its cheap production cost and ability to grow on marginal land. Biofuel derived from switchgrass has been shown to be very energy efficient, producing 540% more renewable energy versus nonrenewable energy expended. Switchgrass-derived biofuel is also estimated to have greenhouse gas emissions that are 94% lower than emissions from gasoline (Schmer et al 2008). Biofuels are created through biochemical processes that utilize various enzymes and microorganisms for …

Beneficial Effects Of Naringenin And Indomethacin On White And Brown Adipocytes, Jamie Ann Kearns

Masters Theses

As obesity continues to grow and medical costs in the United States are estimated at $147 billion annually, novel ways to prevent and treat obesity are needed. One approach is to promote thermogenesis to improve energy balance by increasing the activities of thermogenic brown and beige adipocytes.

Naringenin, a citrus flavanone, has been shown to act as anti-inflammatory and lipid lowering agent as well as activate PPARgamma. However, it is unclear whether it can activate thermogenic activity in white adipocytes, i.e., promote formation of beige adipocytes. Indomethacin (INDO) is an FDA approved drug used to treat pain related to inflammation …

Lignin Maximization: Analyzing The Impact Of Different Feedstocks And Feedstock Ratios Using Organosolv Fractionation, Marc Banholzer

Masters Theses

Over-exploitation of fossil fuels coupled with increasing pressure to reduce carbon emissions are prompting a transition from conventional petrochemical feedstocks to sustainable and renewable sourced carbon. The use of lignocellulosic biomass as a feedstock for integrated biorefining is of current high interest, as separation into its component parts affords process streams of cellulose, hemicellulose and lignin, each of which can serve as a starting point for the production of biobased chemicals and fuels. Given the large number of potential sources of lignocellulosic feedstocks, the biorefinery will need to adapt to the supplies available over a normal growing season. Of particular …

Vegetation Response To Canopy Disturbance And Season Of Burn During Oak Woodland And Savanna Restoration In Tennessee, Andrew Lee Vander Yacht, Seth A. Barrioz, Patrick D. Keyser, Craig A. Harper, David Buckley, David A. Buehler, Roger D. Applegate

UT Extension publication

The removal of fire’s influence on plant community succession has resulted in the near disappearance of oak woodlands and savannas from the Appalachian region. Negative trends in associated plant and wildlife species could be reversed if these communities are restored, but management has been limited by inadequate canopy disturbance, resprouting of woody plants, and a lack of empirical research. To address these issues, we evaluated herbaceous and woody vegetation response on the

Cumberland Plateau in Tennessee to 5 replicated treatments involving canopy reduction and fire-season combinations and unmanaged controls. All categories of woody vegetation except large saplings density, but resprouting …

Reproductive Schedule Of The Silver Shiner (Notropis Photogenis) In The Flint River Of Alabama, Kelly Hodgskins, Stephanie Greenleaf, Jonathan Hillman, Bruce Stallsmith

Southeastern Fishes Council Proceedings

Many river-dwelling species of fish are dependent upon and stimulated by fluctuations in river flow for successful reproduction. This is especially true of pelagophils, a reproductive guild whose eggs and larvae require free drifting on river currents for several days. Notropis photogenis (Silver Shiner) is a rheophilic species with a broad distribution from Ontario to the southeastern United States including northern tributaries to the Tennessee River in Alabama. Little is known of its reproductive biology. The purpose of this study was to describe aspects of reproductive biology such as timing and pattern of ovarian development and oocyte maturation of N. …

Intensive, Regular Sampling And Removal Of Modest Numbers Of Fishes Shows No Measurable Impact On Fish Populations In Three Streams Of North Georgia, Steven L. Powers

Southeastern Fishes Council Proceedings

Recent publications and restrictions on collecting by state fish and game managers indicate a growing concern regarding the impact of field sampling on native fish populations. To evaluate the validity of these concerns, data from five life-history studies conducted in Cherokee County, Georgia were examined to test the hypothesis that regular sampling has a negative impact on fish populations. Number of individuals collected was divided by time collecting to calculate catch per unit effort (CPUE) as an indicator of relative abundance for each species. The collecting sequence (i.e. the number of times a species had previously been sampled) was regressed …

Evolution Of Long Centromeres In Fire Ants, Yu-Ching Huang, Chih-Chi Lee, Chia-Yi Kao, Ni-Chen Chang, Chung-Chi Lin, Dewayne Shoemaker, John Wang

Entomology & Plant Pathology Publications and Other Works

Background: Centromeres are essential for accurate chromosome segregation, yet sequence conservation is low even among closely related species. Centromere drive predicts rapid turnover because some centromeric sequences may compete better than others during female meiosis. In addition to sequence composition, longer centromeres may have a transmission advantage.

Results: We report the first observations of extremely long centromeres, covering on average 34 % of the chromosomes, in the red imported fire ant Solenopsis invicta. By comparison, cytological examination of Solenopsis geminata revealed typical small centromeric constrictions. Bioinformatics and molecular analyses identified CenSol, the major centromeric satellite DNA repeat. We found that …

Investigating Genetic Differences Between Strains Of Janthinobacterium Lividum On Salamanders And In Their Environment, Rhiannon E. Black

Chancellor’s Honors Program Projects

No abstract provided.

Development, Implementation And Evaluation Of A Pilot Intervention: Promoting Breast Milk Expression In A Neonatal Intensive Care Unit, Katherine Marie Bower

Doctoral Dissertations

Background: Very preterm infants receiving breast milk experience better health outcomes compared to formula fed infants. However, these infants often lack the ability to coordinate sucking and swallowing and are unable to breastfeed at delivery. Consequently, mothers of very preterm infants must initiate milk expression. While these mothers demonstrate high milk expression initiation rates, continuation of this behavior until infant discharge from the Neonatal Intensive Care Unit (NICU) is a significant challenge.Therefore, the primary aim of this study was to gain an understanding of mothers’ experiences expressing milk for their very preterm infants in a Level III NICU and to …

Molecular Dynamics Simulations Of Enzymes With Quantum Mechanical/Molecular Mechanical Potentials, Yufei Yue

Doctoral Dissertations

S-adenosyl methionine (SAM) dependent methylation process is universally found in all branches of life. It has important implications in mammalian pathogenesis and plant metabolism. The methyl transfer is normally catalyzed by SAM-dependent methyltransferases(MTases). Two MTases are studied in this dissertation: the 1,7-dimethylxanthine methyltransferase (DXMT) which involve in plant caffeine biosynthesis, and the protein arginine methyltransferase 5(PRMT5) that participates in eukaryotic posttranslational modification. The late phase of caffeine biosynthesis starts from the substrate xanthosine and ends with the product caffeine, with theobromine as an intermediate product. DXMT is a key enzyme in this process and catalyzes two methylation steps: 1)methylation of …

Computational Analyses Of Mrna Ribosome Loading In Arabidopsis Thaliana, Joseph Benjamin Ernest

Doctoral Dissertations

Translation of mRNA into protein is a critical step in gene expression, but the principles guiding its regulation at the genome level are not completely understood. Translation can be quantified at a genome scale by measuring the ribosome loading of mRNA—the extent to which mRNA is associated with ribosomes. In this dissertation, I present investigations into how genome-wide ribosome loading is controlled in Arabidopsis thaliana. In chapter 1, I give an overview of regulation of ribosome loading and translation. In chapter 2, I present research demonstrating for the first time that genome-wide ribosome loading in plants is partially controlled by …

Electron Transport To Photosystem I By Soluble Carriers: Evolution Of The Interacting Pair, Khoa Dang Nguyen

Doctoral Dissertations

Oxygenic photosynthesis is driven via sequential action of Photosystem II (PSII) and (PSI) reaction centers via the Z-­‐scheme. Both of these pigment– membrane protein complexes are found in cyanobacteria, algae, and plants. PSI, unlike PSII, is remarkably stable and does not undergo limiting photo-­‐damage. This stability, as well as other fundamental structural differences, makes PSI the most attractive reaction centers for applied photosynthetic applications. These applied applications exploit the efficient light harvesting and high quantum yield of PSI where the isolated PSI particles are redeployed providing electrons directly as a photocurrent or, via a coupled catalyst to yield H2. Here, …

Improving Metabolic Engineering And Characterization Of Clostridium Thermocellum For Improved Cellulosic Ethanol Production, Beth Alexandra Papanek

Doctoral Dissertations

Biofules are an important option for humanity to move away from its dependence on fossil fuels. Transitioning from food crops to lignocellulosic alternatives for the production of biofuels is equally important. Most commonly, biofuels are produced using a crop such as corn or soybeans to feed sugars to the yeast, Saccharomyces cerevisiae for the fermentation of ethanol. Lignocellulosic biofuel production would eliminate the need for food crops and transition to biomass such as switchgrass, poplar, or corn stover. Currently, lignocellulosic biofuel production is limited primarily because of the cost of converting the biomass to fermentable sugars than can then be …

Effects Of Television Viewing On Psycho-Physiological And Behavioral Outcomes, Brittany Star Overstreet

Doctoral Dissertations

Purpose: To determine the effects of television viewing during exercise on 1) preference for exercise and 2) treadmill walking time. Methods: Twenty-five insufficiently active adults (mean±standard deviation; age: 46±12 years; Body mass index: 31±5 kilogram/squared meter (kg/m²) were recruited for this study. In part 1, participants performed three randomized 1/3-mile walking bouts at an intensity equivalent to 70% of their oxygen consumption at ventilatory threshold (VO₂-at-VT). During these exercise bouts, individuals viewed 1) their favorite television program (FavTV), 2) a standardized nature program (NatTV) or 3) no-TV program (NoTV). A behavioral choice paradigm was used to …

Modification Of Carbohydrate Active Enzymes In Switchgrass (Panicum Virgatum L.) To Improve Saccharification And Biomass Yields For Biofuels, Jonathan Duran Willis

Doctoral Dissertations

The natural recalcitrance of plant cell walls is a major commercial hurdle for plant biomass to be converted into a viable energy source as alternative to fossil fuels. To circumvent this hurdle manipulation of carbohydrate enzymes active in the cellulose and hemicellulose portions of the plant cell wall can be utilized to improve feedstocks. Production of cellulolytic enzymes by plants have been evaluated for reducing the cost associated with lignocellulosic biofuels. Plants have successfully served as bioreactors producing bacterial and fungal glycosyl hydrolases, which have altered plant growth to improve saccharification. A bioprospecting opportunity lies with the utilization of insect …

The Effects Of Exogenous Fatty Acids On Enterococcus Faecalis Og1rf, Holly Elizabeth Johnson Saito

Doctoral Dissertations

Enterococcus faecalis is a commensal of the mammalian intestine and an opportunistic pathogen that infects various locations in the human host. Specifically, the organism can infect surgical wounds, the urinary tract, and is an agent of endocarditis. Regardless of niche, this organism has access to fatty acid sources in the host, which may influence its ability to survive and cause infection; yet, the effects of exogenous fatty acids were unknown in E. faecalis. We have shown that complex sources of fatty acids such as bile or serum can significantly alter the membrane content and protect E. faecalis from acute …

Long-Term Treatment With Insulin And Retinoic Acid Increased Glucose Usage In L6 Muscle Cells Via Glycogenesis, Matthew Ray Goff

Doctoral Dissertations

Skeletal muscle glucose metabolism can affect whole body glucose homeostasis significantly. Vitamin A (VA) plays a role in a number of physiological functions including glucose metabolism. However, its role in skeletal muscle glucose metabolism has not been well established. Insulin controls glucose metabolism in the skeletal muscle via the regulations of glucose uptake, glycogenesis, and glycolysis. We hypothesize that insulin and VA signaling pathways may converge to regulate glucose metabolism in skeletal muscle. Here, the effects of retinoic acid (RA) alone and in combination with insulin on glucose utilization in rat L6 muscle cells were studied. L6 cells were treated …

Decoding The Cellular Zipcode: Functional Analysis Of Transit Peptide Motifs And Mechanistic Implications In Plastid Targeting And Import, Kristen N. Holbrook

Doctoral Dissertations

Eukaryotic organisms are defined by their compartmentalization and various organelles. The membranes that define these organelles require complex nanomachines (known as translocons) to selectively mediate the import of proteins from the cytosol where they are synthesized into the organelle. The plastid, (specifically the chloroplast) which is characteristic of plant cells, possibly represents the most complex system of protein sorting, requiring many different translocons located in the three membranes found in this organelle. Despite having a small genome, the vast majority of plastid-localized proteins are nuclear-encoded and must be post-translationally imported from the cytosol. These proteins are encoded as a larger …

Anaerobic Soil Disinfestation: Meta-Analysis And Optimization Of Amendment Carbon Rate And C:N Ratio To Control Key Plant Pathogens And Weeds, Utsala Shrestha

Doctoral Dissertations

Anaerobic soil disinfestation (ASD) is an environmentally friendly and cost effective pre-plant soil treatment technique that allows effective control of soilborne pests by creating anaerobic conditions, particularly for specialty and organic crop production under diverse environmental conditions. In spite of being a proven technique, ASD has to be optimized to fit into local production systems with specific pathogen pressure using locally available amendments for successful implementation on a commercial scale. Our meta-analysis study on soilborne pathogens, plant parasitic nematodes, and weeds validated that ASD is an effective approach to control various soilborne pathogens. This study aims to optimize the carbon …

Characterization Of An Ethylene Receptor In Synechocystis Sp. Pcc 6803, Randy Francis Lacey

Doctoral Dissertations

In plants, ethylene functions as a hormone regulating many growth and developmental processes. Ethylene receptors in plants resemble bacterial two-component signaling systems. Because of this it, ethylene receptors are thought to have been acquired by gene transfer from the cyanobacterial endosymbiont that lead to the development of the chloroplast. However, prior to this work, functional ethylene receptors were thought to only be found in green plants. Here, we show that the cyanobacterium Synechocystis sp. PCC 6803 (Synechocystis) contains a functional ethylene receptor, SynEtr1. SynEtr1 contains a predicted ethylene binding domain, a photosensory cyanobacteriochrome (CBCR) domain, and a histidine …

Pigment Dispersing Factor: Transcriptional Regulation And Its Role In Metabolism In Drosophila Melanogaster, Sudershana Nair

Doctoral Dissertations

Almost all living organisms have circadian clocks coordinating physiology and behavior, and an innate molecular clock drives rhythmic changes by integrating environmental and metabolic stimuli to generate 24 hour timing. Drosophila melanogaster has proved to be an excellent model organism with a well-characterized circadian clock and the neural circuits underlying clock have been intensely investigated. The neuropeptide pigment-dispersing factor (PDF) plays an essential role in maintaining circadian rhythmicity and synchronizes circadian clock neurons. However, the regulation of Pdf has been a black box with no known protein identified that directly regulates it, and its role in metabolism hasn’t been looked …

Nanocomposite Adhesive Of English Ivy (Hedera Helix): Bioproduction, Nanoparticle Isolation, And Molecular Analysis, Jason Neil Burris

Doctoral Dissertations

English ivy naturally produces organic nanoparticles from its adventitious root hairs, and possesses characteristics that may allow them to replace metal-based nanoparticles in common applications, such as sunscreen. At the onset of the research, it was hypothesized that a physical mechanism of attachment, similar to the gecko footpad, was used to generate the adhesive force for attachment; however, through the results obtained from recent work, it is clear that a biochemical mechanism is involved in the generation of the strength of adhesion. Therefore, the goal of this research was to provide a better understanding of the genetic basis of nanoparticle …

Multilayered Regulation Of The Type I Toxin Zoro In Ehec, Jia Wen

Doctoral Dissertations

A bacterial type I toxin-antitoxin system contains two genes: one encodes a small toxic protein and the second, a small regulatory RNA (sRNA) that inhibits toxin production. To date, very few type I loci have been described thoroughly in regards to the regulation of toxin and the function of the toxin at endogenous levels. In this study, I demonstrated that the zor-orz locus of Escherichia coli O157:H7 is composed of two highly homologous type I toxin-antitoxin systems: zorO-orzO and zorP-orzP. The zor genes encode the toxins and the orz genes encode the antitoxin sRNAs. Overexpression of zorO is toxic …

Metabolomics Approaches To Decipher The Antibacterial Mechanisms Of Yerba Mate (Ilex Paraguariensis) Against Staphylococcus Aureus And Salmonella Enterica Serovar Typhimurium, Caroline Sue Rempe

Doctoral Dissertations

The increasing prevalence of drug-resistant pathogens is an urgent problem that requires novel methods of bacterial control. Plant extracts inhibit bacterial pathogens and could contain antibacterial compounds with novel mechanisms of action. Yerba mate, a common South American beverage made from Ilex paraguariensis, has antibiotic activity against a broad range of bacterial pathogens. In this work, an attempt was first made to characterize the antibacterial source of an aqueous yerba mate extract by generating a series of extract fractions, collecting GC-MS and antibacterial activity profiles, and then ranking the hundreds of compounds by their presence in fractions with high antibacterial …

Sorghum Phenolic Extracts: Chemical Characterization And Biological Activity Determination, James Jordan Bradwell

EURēCA: Exhibition of Undergraduate Research and Creative Achievement

Red sorghum contains phytochemicals such as 3-deoxyanthocyanidins and flavonoids with reported health benefits. The objective was to determine the chemical composition of sorghum phenolic extracts that were extracted with acidified methanol and separated into co-pigments and anthocyanin fraction by chromatographic procedure. In addition, the ability of sorghum extract to modify activation of the inflammasomes, a macromolecular protein complex involved in several malignancies, was evaluated. The total polyphenols, total flavonoids and total anthocyanins of the sorghum phenolic extract was quantified and phenolic profile was determined by high performance liquid chromatography. The ability to modify the inflammasomes was evaluated using THP-1 human …

Pinpointing The Molecular Basis For Metal Ion Effects On Plasminogen Activator Inhibitor-1 (Pai-1), Joel Cullen Bucci

Doctoral Dissertations

Plasminogen activator inhibitor type-1 (PAI-1) specifically inhibits the proteases tissue type plasminogen activator and urokinase plasminogen activator to control the activation of fibrinolysis. Vitronectin interacts with PAI-1 primarily through the somatomedin B (SMB) domain to stabilize and localize PAI-1 to sites of injury. Our laboratory observed that transition metals such as copper²⁺ have VN dependent, reciprocal effects on how long PAI-1 remains active. We aim to determine the molecular basis for effects of copper²⁺ on PAI-1 activity. We employed a computational algorithm (MUG) to predict metal binding clusters, and introduced mutations hypothesized to create metal binding deficiency. We …

New Insights Into An Old Interaction: Developing A Model For Pai-1:Vn Interactions, Letitia Nichole Puster

Doctoral Dissertations

Active human Plasminogen Activator Inhibitor 1 (PAI-1) is most often found in complex with Vitronectin (VN), an ~62kDa glycoprotein. Research has shown PAI-1 and VN form higher order complexes in tissues, and our work indicates a 2:1 (PAI-1:VN) stoichiometry for these complexes. A logical model for PAI-1:VN interaction proposes that two PAI-1 molecules bind VN at separate sites. However, our small-angle neutron scattering (SANS) data suggest that there is a PAI-1: PAI-1:VN interaction, in which PAI-1 forms a dimer when in complex with VN. We tested this novel arrangement of PAI-1 within the complex by using a variety of biophysical …

Evaluation Of Total Mercury And Methylmercury Concentrations Of Terrestrial Invertebrates Along Lower East Fork Poplar Creek In Oak Ridge, Tennessee, Chelsea Lynden Standish

Masters Theses

Mercury (Hg) and methylmercury (MeHg) are environmental concerns due to their abilities to cause neurological, reproductive, and other physical damage to wildlife. Lower East Fork Poplar Creek (LEFPC), stemming from the Y-12 National Security Complex, located in Oak Ridge, TN, has elevated concentrations of inorganic mercury, a majority of which was released between 1950 and 1963. This inorganic mercury has been, and is currently, converted to methylmercury. An ecological assessment in 2011 revealed high concentrations of methylmercury in riparian spiders along LEFPC. These results suggested the transfer of mercury from aquatic to terrestrial systems may be higher than previously expected …

The Effect Of Heat Stress And Essential Amino Acids On Production And Metabolism Of Lactating Dairy Cattle, Kimberly Rose Kassube

Masters Theses

Heat stress (HS) causes decreases in production of lactating cattle that is only partially explained by decreases in intake. Evidence suggests that changes in energy and protein metabolism occur to cope with the impact of HS. The objective of this thesis was to determine if the effect of jugular infusion of essential amino acids (AA) ameliorated the negative effects of HS in milk production and metabolism. Twelve multiparous lactating Holstein cows were used in a crossover design to evaluate the effect of thermoneutral (THN) and HS environments along with the absence (CTL) …