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Morphological And Phylogenetic Resolution Of Diplodia Spp., Emerging Canker Pathogens Of Oak (Quercus Spp.), In The United States, Savannah Lyn Ferreira Jan 2019

Morphological And Phylogenetic Resolution Of Diplodia Spp., Emerging Canker Pathogens Of Oak (Quercus Spp.), In The United States, Savannah Lyn Ferreira

Graduate Theses, Dissertations, and Problem Reports

In Mediterranean Europe and the United States, oak species (Quercus spp.) have been in a state of declining health and vigor for the past several decades. Several biotic agents have been found to contribute to this decline to varying degrees including Phytophthora cinnamomi and Armillaria spp., both causal agents of root rots, and various insect defoliators. In the U.S., Bretziella fagacearum, the causal agent of oak wilt, has also been implicated. More recently, Diplodia corticola (Dc) and other Diplodia spp. have been implicated in causing dieback and mortality of oak species in Europe and in …


Lignocellulosic Biomass Derived Activated Carbon For Energy Storage And Adsorption, Changle Jiang Jan 2019

Lignocellulosic Biomass Derived Activated Carbon For Energy Storage And Adsorption, Changle Jiang

Graduate Theses, Dissertations, and Problem Reports

Lignocellulosic biomass has been converted to hierarchical porous carbon materials which possess macro-, meso- and micro-pores. The natural structure of porous lignocellulosic structure was preserved during activation with further developed porosity by the activation. The activated carbon can be well applied to electrochemical double layer capacitor for transportation storage of ions as well as adsorbent materials for metal ion removal from wastewater.

The first chapter of this dissertation presents an introduction of biomass derived carbon and its applications. In the second chapter, both direct and indirect activation methods using carbon dioxide were adopted in this study. The results show that …


Cerulean Warbler (Setophaga Cerulea) And Associated Species Response To Operational Silviculture In The Central Appalachian Region, Gretchen Emily Nareff Jan 2019

Cerulean Warbler (Setophaga Cerulea) And Associated Species Response To Operational Silviculture In The Central Appalachian Region, Gretchen Emily Nareff

Graduate Theses, Dissertations, and Problem Reports

In this study, I assessed the response of Cerulean Warblers (Setophaga cerulea) and 5 additional songbird species to timber harvests prescribed through operational silviculture. The research took place in relatively contiguous mature deciduous forests in 4 states in the central Appalachian region—Kentucky, Pennsylvania, Virginia, and West Virginia, USA.

For the first part of the study, I collected Cerulean Warbler abundance and territory data through point counts and territory mapping, respectively. I used the point count data to model Cerulean Warbler abundance pre- and post-harvest at 5 study areas (Kentucky [n=1], Virginia [n=2], West Virginia [n=2]) and post-harvest at …


Metal Nanomaterials: Immune Effects And Implications Of Physicochemical Properties On Sensitization, Elicitation, And Augmentation Of Allergic Disease, Katherine Adair Roach Jan 2019

Metal Nanomaterials: Immune Effects And Implications Of Physicochemical Properties On Sensitization, Elicitation, And Augmentation Of Allergic Disease, Katherine Adair Roach

Graduate Theses, Dissertations, and Problem Reports

Many allergenic metals are being manufactured in nanoparticulate forms. Although the decreased size profile of metal nanomaterials has been consistently associated with more pronounced lung toxicity compared to larger materials, it is unclear if metal-induced immunotoxic effects exhibit a similar size-dependency.

The central hypothesis of these studies was that metal nanoparticles cause more pronounced immunomodulatory effects on allergic processes than larger forms of respective metals. Moreover, it was anticipated that, similar to their inflammatory potential in airways, the magnitude of these responses would correlate best with the dose metric of surface area.

The first set of studies utilized fine and …


Discrimination And Behavioral Responses To Communication Signals Compared Across Apteronotids., Danielle Leigh Dillon-Seeger Jan 2019

Discrimination And Behavioral Responses To Communication Signals Compared Across Apteronotids., Danielle Leigh Dillon-Seeger

Graduate Theses, Dissertations, and Problem Reports

Sensory systems are often uniquely tailored to encode behaviorally relevant signals and comparative studies across species can thus reveal how evolutionary changes shape sensory functions. The structure of communication signals varies widely between ghost knifefish species. Recent findings suggest that the nervous system co-adapted to the various signal structures observed across species to support different sensory behaviors. The aim for this thesis was to compare the sensory behavior of 3 species of ghost knifefish to contrast their behavioral performance with the known differences in neurophysiology. We hypothesize that for the different signal types and species, the ability to discriminate small …


Thermal Performance Of Growth At Consumption Maximum (C-Max) And Routine Metabolic Rate (Rmr) In Brook Trout Salvelinus Fontinalis From Four Populations In Central Appalachia, Cory Michael Hartman Jan 2019

Thermal Performance Of Growth At Consumption Maximum (C-Max) And Routine Metabolic Rate (Rmr) In Brook Trout Salvelinus Fontinalis From Four Populations In Central Appalachia, Cory Michael Hartman

Graduate Theses, Dissertations, and Problem Reports

Growth of an individual is the end result of many physiological processes stemming from the consumption of food items. These processes can be influenced by many variables including temperature. Current bioenergetics models for Brook Trout Salvelinus fontinalis suggest growth increases with temperature until an inflection point of 20.2°C. With a warming climate, and water temperatures expected to rise, the ability of a population to adapt to the warming environment is crucial to the survival of the species. For this study we sought to see how spatial variation would influence the specific consumption, conversion efficiency, and specific growth at consumption maximum …


Genet-Cnv: Boolean Implication Networks For Modeling Genome-Wide Co-Occurrence Of Dna Copy Number Variations, Salvi Singh Jan 2019

Genet-Cnv: Boolean Implication Networks For Modeling Genome-Wide Co-Occurrence Of Dna Copy Number Variations, Salvi Singh

Graduate Theses, Dissertations, and Problem Reports

Lung cancer is the leading cause of cancer-related death in the world. Lung cancer can be categorized as non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC). NSCLC makes up about 80% to 85% of lung cancer cases diagnosed, whereas SCLC is responsible for 10% to 15% of the cases. It remains a challenge for physicians to identify patients who shall benefit from chemotherapy. In such a scenario, identifying genes that can facilitate therapeutic target discoveries and better understanding disease mechanisms and their regulation in different stages of lung cancer, remains an important topic of research.

In this …


Aptamer Functionalized Zinc Oxide Field Effect Transistors For Odor Detection, Michael D. Aldridge Jan 2019

Aptamer Functionalized Zinc Oxide Field Effect Transistors For Odor Detection, Michael D. Aldridge

Graduate Theses, Dissertations, and Problem Reports

Odor detection and identification are complex processes, and tasks that currently only animals do well. There is a pressing need for an electronic nose, or eNose, with good sensitivity, selectivity, and speed that mimics that ability. Food quality control operations, environmental sensing, occupational safety, and the defense sectors all require systems that can rapidly and reliably detect trace levels of volatile organic compounds. The goal of this work is to create a biologically inspired device which can accurately detect and identify odors at concentrations consistent with the most sensitive biological systems.

In order to mimic a natural olfactory system, we …


Crown-Level Mapping Of Tree Species And Health From Remote Sensing Of Rural And Urban Forests, Fang Fang Jan 2019

Crown-Level Mapping Of Tree Species And Health From Remote Sensing Of Rural And Urban Forests, Fang Fang

Graduate Theses, Dissertations, and Problem Reports

Tree species composition and health are key attributes for rural and urban forest biodiversity, and ecosystem services preservation. Remote sensing has facilitated extraordinary advances in estimating and mapping tree species composition and health. Yet previous sensors and algorithms were largely unable to resolve individual tree crowns and discriminate tree species or health classes at this essential spatial scale due to the low image spectral and spatial resolution. However, current available very high spatial resolution (VHR) remote sensing data can begin to resolve individual tree crowns and measure their spectral and structural qualities with unprecedented precision. Moreover, various machine learning algorithms …


Evaluating The Potential Of Methyl Jasmonate Application As An Agricultural Practice On Phytochemicals In Brassica Vegetables: Sensory Quality, Cooking, And Cost-Benefit Analysis, Yu-Chun Chiu Jan 2019

Evaluating The Potential Of Methyl Jasmonate Application As An Agricultural Practice On Phytochemicals In Brassica Vegetables: Sensory Quality, Cooking, And Cost-Benefit Analysis, Yu-Chun Chiu

Graduate Theses, Dissertations, and Problem Reports

In the United States, Brassica vegetables, including broccoli (Brassica oleracea var. italica) and kale (Brassica oleracea var. acephala or Brassicae napus var. pabularia), are widely consumed and are easily accessible in farmer’s market or grocery stores with increasing interest of their health-promoting properties. For example, the consumption of broccoli has been associated with anti-cancer activity in in vitro and in vivo trails due to the high content of phytochemicals, minerals, vitamins, and fibers. Application of methyl jasmonate (MeJA) has been reported to enhance the potential health-promoting compounds in Brassica vegetables, glucosinolates (GS), especially indolyl GS neoglucobrassicin …


Association Genetics And Local Adaptation Of Populus Trichocarpa Torr. & Gray, Hari Bahadur Chhetri Jan 2019

Association Genetics And Local Adaptation Of Populus Trichocarpa Torr. & Gray, Hari Bahadur Chhetri

Graduate Theses, Dissertations, and Problem Reports

A major goal in plant science is overcoming the recalcitrance of plant biomass to cellulose extraction, to enable efficient production of cellulosic biofuel. We have started to understand the genetic basis of some important traits such as cell wall chemistry, but we do not know anything about the key structural and functional traits such as wood anatomy that greatly affect plant biomass recalcitrance. Furthermore, biofuel feedstocks have to be adapted to varied environmental conditions to ensure high productivity in plantations, but little is known about the molecular mechanisms underlying local adaptation. With the advancement in sequencing and genotyping technologies, association …


Apple Pomace As A Novel Aid For Western Diet-Induced Nonalcoholic Fatty Liver Disease In Young Female Sprague Dawley Rats, R. Chris Skinner Jan 2019

Apple Pomace As A Novel Aid For Western Diet-Induced Nonalcoholic Fatty Liver Disease In Young Female Sprague Dawley Rats, R. Chris Skinner

Graduate Theses, Dissertations, and Problem Reports

Apple pomace is a “waste” byproduct of apple processing that causes environmental pollution and is costly to dispose of. Yet, apple pomace is rich in dietary fibers and antioxidants. Analysis of apple pomace’s nutritional profile indicates suitability as a potential dietary treatment for non-alcoholic fatty liver disease (NAFLD) and the more severe non-alcoholic steatohepatitis (NASH). NAFLD is the most prevalent liver disease in the world with prevalence and severity expected to increase in both adults and children. Currently, there is no approved drug treatment for NAFLD and therefore, dietary intervention is the primary treatment. The study objectives were to determine …


The Impact Of Tree Species, Elevated Nitrogen Deposition, Stand Age, And Environmental Factors On Herbaceous Plant Communities In A Central Appalachian Hardwood Forest, Lacey J. Smith Jan 2019

The Impact Of Tree Species, Elevated Nitrogen Deposition, Stand Age, And Environmental Factors On Herbaceous Plant Communities In A Central Appalachian Hardwood Forest, Lacey J. Smith

Graduate Theses, Dissertations, and Problem Reports

Although the herb layer represents less than 1% of the biomass of temperate forests, this layer may contain up to 90% of the plant species in the forest and can contribute up to 20% of the foliar litter, thus playing an essential role in forest biodiversity and nutrient cycling. The objectives of this study were to investigate the differences in cover, species richness, Shannon-Wiener diversity, and evenness of herb layer plants a) under tree species associated with contrasting soil nitrogen levels and b) in watersheds that vary in nitrogen deposition, stand age, and watershed aspect at the Fernow Experimental Forest …


Critical Physicochemical Properties For Nanoparticle Toxicity: Impact Of Surface Coating And Size On Particle-Induced Cell Transformation And Inflammatory Response, Tiffany Kornberg Jan 2019

Critical Physicochemical Properties For Nanoparticle Toxicity: Impact Of Surface Coating And Size On Particle-Induced Cell Transformation And Inflammatory Response, Tiffany Kornberg

Graduate Theses, Dissertations, and Problem Reports

Nanoparticles, which measure 100 nm in at least one dimension, have surged in development, production, and use for a wide range of applications. However, the rapid pace of development for these emerging materials with unclear/unknown toxicity profiles makes it difficult to adequately assess health risk associated with exposure. One critical obstacle which limits scientific research to fill these critical knowledge gaps is the lack of accurate and predictive models for nanotoxicology studies, particularly those which involve occupationally relevant exposure scenarios (pulmonary exposure to low dose of particles in the circulating air). Typically, animal models are used to assess potential systemic …


Demographic, Spatial, And Epigenetic Response Of The Louisiana Waterthrush (Parkesia Motacilla) To Shale Gas Development, Mack W. Frantz Jan 2019

Demographic, Spatial, And Epigenetic Response Of The Louisiana Waterthrush (Parkesia Motacilla) To Shale Gas Development, Mack W. Frantz

Graduate Theses, Dissertations, and Problem Reports

My study centered on a bioindicator songbird, the Louisiana Waterthrush (Parkesia motacilla), hereafter waterthrush, an organism that co-occurs in both forested and aquatic habitat across the aquatic-terrestrial interface. This enabled the opportunity to quantify demographic, spatial, and epigenetic (i.e., DNA methylation) responses in a highly forested watershed of the Central Appalachians, the areas that have undergone the most rapid transformations over the last decade from unconventional shale gas development and activities. I organized my dissertation into 4 parts (Part 1: Introduction, Part 2: Louisiana Waterthrush Demography, Part 3: Spatial Assessment of Louisiana Waterthrush Foraging, Part 4: Louisiana Waterthrush …


Regulation Of The Long Non-Coding Rna Fam83h-As1 By Human Papillomavirus In Cervical Cancer, Jamie Ann Barr Ph.D. Jan 2019

Regulation Of The Long Non-Coding Rna Fam83h-As1 By Human Papillomavirus In Cervical Cancer, Jamie Ann Barr Ph.D.

Graduate Theses, Dissertations, and Problem Reports

Non-coding RNAs (NcRNAs), such as long non-coding RNAs (lncRNAs) and microRNAs (miRNAs), have been found to be involved in a variety of critical biological processes, and dysregulation of ncRNAs have been involved with several human diseases including cancer.

High-risk human papillomavirus (HPV) infection is one of the first events in the process of carcinogenesis in cervical and a subset of head and neck cancers. The expression of the viral oncoproteins E6 and E7 is essential in this process by inactivating the tumor suppressor proteins p53 and Rb, respectively, in addition to their interactions with other host proteins and regulation of …


Role Of Extracellular Vesicles In Neuroinflammatory Progression And Mitochondrial Functional Alterations, Ashley E. Russell Jan 2019

Role Of Extracellular Vesicles In Neuroinflammatory Progression And Mitochondrial Functional Alterations, Ashley E. Russell

Graduate Theses, Dissertations, and Problem Reports

Inflammation within the central nervous system (CNS), termed neuroinflammation, is a defining characteristic of many neuropathological conditions, including Alzheimer’s disease (AD) and stroke. Certain inflammatory mediators activate the transcription factor NF-κB, which induces transcription of many pro-inflammatory genes, including miR-34a and miR-146a. Several target candidate genes of these miRNAs encode for proteins of the mitochondrial electron transport chain. In our studies, we demonstrate that in response to inflammatory stimuli, such as TNF-α, the expression of miR-34a and -146a is significantly increased in several CNS cell types, and in their secreted extracellular vesicles (EVs). Exposure to TNF-α-derived EVs significantly increases cellular …


The Effect Of Bovine Galectin-1, A Conceptus Secretory Protein, On The Endometrial Transcriptome, Lindsay Faye Grose Jan 2019

The Effect Of Bovine Galectin-1, A Conceptus Secretory Protein, On The Endometrial Transcriptome, Lindsay Faye Grose

Graduate Theses, Dissertations, and Problem Reports

Early embryonic loss in cattle is detrimental to reproduction thus, the profitability of both the beef and dairy industries. Therefore, an important aspect of study is to find techniques that beef or dairy producers could use to decrease early embryonic loss Galectin-1, the protein that was investigated in this research is important in modulating the maternal immune system in rodent and human early pregnancies by promoting fetomaternal immune tolerance. The role of galectin-1 within the reproductive tissues has not been thoroughly investigated in cattle. Galectin-1 is located in the caruncular and intercaruncular regions of the bovine endometrium, specifically the maternal …


Optimization Of Engineered Super Donor Strains Of Cryphonectria Parasitica To Reduce Canker Expansion In A Forest Setting, Amy Michelle Metheny Jan 2019

Optimization Of Engineered Super Donor Strains Of Cryphonectria Parasitica To Reduce Canker Expansion In A Forest Setting, Amy Michelle Metheny

Graduate Theses, Dissertations, and Problem Reports

Chestnut blight, caused by the non-native fungus Cryphonectria parasitica, has decimated American chestnut (Castanea dentata) populations throughout the eastern U.S. over the last century. Biological control of blight, termed hypovirulence, has emerged naturally in the form of a debilitating hypovirus transmitted through hyphal anastomosis among vegetatively compatible C. parasitica strains. Six unlinked vegetative incompatibility (vic) loci regulate hyphal anastomosis and thus, hypovirus transmission, which has limited biocontrol efficacy in genotypically diverse communities. Recently, four of six vic loci have been disrupted to engineer two “super donor” or SD strains. In combining these strains, enhanced transmission …


Population Health Of Spotted Salamanders (Ambystoma Maculatum) In Created Vernal Pools: An Integrative Approach, Alice R. Millikin Jan 2019

Population Health Of Spotted Salamanders (Ambystoma Maculatum) In Created Vernal Pools: An Integrative Approach, Alice R. Millikin

Graduate Theses, Dissertations, and Problem Reports

Habitat creation is an important tool for conservation to counteract habitat loss and degradation. Vernal pools are susceptible to destruction due to limited detection, protection, and regulation. These wetlands provide fishless breeding habitat for many amphibian species including spotted salamanders (Ambystoma maculatum) in eastern North America. Determining whether created vernal pool habitat is successful is often determined by demographic data of colonizing populations. I suggest that hormone levels, population genetics, and disease prevalence can improve our understanding of population health in created habitat. The goal of this dissertation was to assess the health of spotted salamander larvae in …


Analysis Of Unconventional Oil And Gas Impacts On Downstream Fish Assemblages And Physiological Stress, Joshua Noah Ankeny Jan 2019

Analysis Of Unconventional Oil And Gas Impacts On Downstream Fish Assemblages And Physiological Stress, Joshua Noah Ankeny

Graduate Theses, Dissertations, and Problem Reports

Unconventional Oil and Gas (UOG) production has been steadily expanding throughout the mid-Atlantic since 2008. Increased sedimentation, degraded water chemistry and an overall decrease in habitat quality due to UOG is anticipated to negatively impact aquatic inhabitants, a common observation in other stressed landscapes (i.e., mining, agriculture, development). We assessed stream health through both community analysis and physiological parameters (i.e., growth and hematocrit). A before-after-control-impact study uncovered three fish metrics that were significantly different following UOG disturbances. The invertivore-piscivore metric decreased following UOG disturbance (p = 0.045) whereas two benthic metrics saw a surprising increase (p = 0.003 and p …


Estimating The Age Of A Bloodstain Using Droplet Digital Pcr, Kalee Rae Crampton Jan 2019

Estimating The Age Of A Bloodstain Using Droplet Digital Pcr, Kalee Rae Crampton

Graduate Theses, Dissertations, and Problem Reports

Biological evidence is extremely valuable in the investigation of a crime due to the presence of DNA. DNA evidence is considered the gold standard in court cases due to its ability to link a suspect to a piece of evidence. In addition to DNA evidence, biological stains have the potential to provide a temporal link between an individual and a crime scene. Previous studies have shown that relative rates of RNA degradation can be used in order to estimate the age of bloodstains. Here, we examined the ability of droplet digital PCR to be used in place of quantitative PCR …


Evaluating The Effects Of Exogenous Enzyme Supplementation On Broiler Growth, Victoria E. Ayres Jan 2019

Evaluating The Effects Of Exogenous Enzyme Supplementation On Broiler Growth, Victoria E. Ayres

Graduate Theses, Dissertations, and Problem Reports

Experiments were conducted to investigate the effects of exogenous enzymes in poultry diets. In Chapter 4, a study was conducted to determine the effects of a corn-expressed recombinant carbohydrase (AC1) on broiler performance and digesta viscosity in high non-starch polysaccharide (NSP) diets through 21 days of age. One day-old Hubbard × Cobb 500 chicks were assigned to 6 dietary treatments. Each treatment consisted of 12 replicate pens of 10 birds. The positive control diet (PC) was a corn and soybean meal formulation. The negative control diet (NC) included 10% wheat and 10% corn distiller’s dried grains with solubles (DDGS). The …


Improving Broiler Performance Utilizing Modern Feed Additives, Niles Rourke Ridgeway Jan 2019

Improving Broiler Performance Utilizing Modern Feed Additives, Niles Rourke Ridgeway

Graduate Theses, Dissertations, and Problem Reports

Modern broiler production strives to make modest improvements regarding broiler performance. This remains a goal as global population increases thusly increasing the quantity of an affordable, high quality source of protein. In recent years, an added stressor to achieving prior goals is mostly related to consciousness of environmental and consumer health. For decades, integrators have utilized minimal amounts of antibiotics as a barrier to most pathogens affecting the microbiome of a broiler’s gastrointestinal tract. Regulatory efforts have now prohibited most of previous sub-therapeutic medicine and started an in-depth scope of broiler gut health and interaction with antibiotic alternatives. In an …


Detecting Balsam Woolly Adelgid Infestations Using Tree Rings, Morgan Lane Leef Jan 2019

Detecting Balsam Woolly Adelgid Infestations Using Tree Rings, Morgan Lane Leef

Graduate Theses, Dissertations, and Problem Reports

Balsam woolly adelgid (BWA), Adelges piceae(Ratzeburg), is a sap-sucking, exotic invasive insect that arrived in North America from central Europe around 1900. Since then, its range has expanded from New Brunswick, Canada to the southern Appalachian Mountains. It is a threat to all North American true-fir species, but populations can be controlled by cold continental winters. Adelgid feeding leaves noticeable traces on the wood tissue (“rotholz”) and causes a temporary positive radial growth response among affected trees. The purpose of this research was to determine dates of initial outbreaks, balsam fir radial growth change during outbreaks, and the relationship …


Probability Discounting Of Lewis And Fischer 344 Rats: Strain Comparisons At Baseline And Following Acute Administration Of D-Amphetamine, Jenny E. Ozga Jan 2019

Probability Discounting Of Lewis And Fischer 344 Rats: Strain Comparisons At Baseline And Following Acute Administration Of D-Amphetamine, Jenny E. Ozga

Graduate Theses, Dissertations, and Problem Reports

Risky choice can be defined as choice for a larger, uncertain reinforcer over a smaller, certain reinforcer when choosing the smaller alternative maximizes reinforcement. Risky choice is studied using various procedures in the animal laboratory; one such procedure is called probability discounting. There are many variables that contribute to risky decision-making, including biological and pharmacological determinants. The present study assessed both of these variables by evaluating dose-response effects of d-amphetamine on risky choice of Lewis (LEW) and Fischer 344 (F344) rats. The probability-discounting procedure included discrete-trials choices between one food pellet delivered 100% of the time and three food …


Evaluating Post-Fire Plantation Restoration In A Mixed Conifer Forest In The Sierra Nevada, Iris C. Allen Jan 2019

Evaluating Post-Fire Plantation Restoration In A Mixed Conifer Forest In The Sierra Nevada, Iris C. Allen

Graduate Theses, Dissertations, and Problem Reports

Forests in the western United States have experienced a shift from historical disturbance regimes in the past century. Many of these changes were induced by European settlers logging the forests and suppressing fires. In the past, the dry mixed conifer forests of California’s Sierra Nevada mountains experience frequent, low to mixed severity fires. This fire regime helped maintain a heterogeneous landscape comprised of groups of trees and openings. However, due to fire suppression and high grading logging, forest structure has changed; there are less openings and more small, fire-intolerant trees that can carry a fire into the forests crown. The …


Mine Reclamation Using Biofuel Crops: Insights Into The Microbial Ecology Of The Switchgrass (Panicum Virgatum) Microbiome, Brianna L. Mayfield Jan 2019

Mine Reclamation Using Biofuel Crops: Insights Into The Microbial Ecology Of The Switchgrass (Panicum Virgatum) Microbiome, Brianna L. Mayfield

Graduate Theses, Dissertations, and Problem Reports

Bioenergy crop production has steadily increased due to growing political support for renewable energy, thus initiating a demand to find alternative agricultural land. An innovative option is the use of marginal soils, such as reclaimed mine lands, to produce bioenergy crops. Switchgrass (Panicum virgatum) is a promising bioenergy crop that can be grown on marginal lands due to its robust growth in various soil types and climates. However, little is known regarding plant-microbe interactions among switchgrass systems within reclaimed mine lands. A study conducted in 2008 grew switchgrass on high- and low- quality reclaimed mine sites (Hampshire and …


Morphological And Functional Evidence Of Sexual Dimorphism In The Retrochiasmatic Area Population Of Nk3r-Containing Neurons In Sheep, Justin A. Lopez Jan 2019

Morphological And Functional Evidence Of Sexual Dimorphism In The Retrochiasmatic Area Population Of Nk3r-Containing Neurons In Sheep, Justin A. Lopez

Graduate Theses, Dissertations, and Problem Reports

Neurokinin B (NKB) and kisspeptin are critical for fertility and potent stimulators of gonadotropin-releasing hormone (GnRH) and luteinizing hormone (LH) secretion in sheep. We previously demonstrated that administration of NKB receptor (NK3R) agonist, senktide, within the retrochiasmatic area (RCh) resulted in surge-like release of LH and increased expression of kisspeptin neurons in the arcuate nucleus (ARC) of female lambs. We concluded that NKB-responsive neurons in the RCh stimulate GnRH secretion by inducing kisspeptin release from neurons in the ARC.

We have demonstrated morphological and functional evidence of sexual dimorphism in NKB-NK3R signaling in ovine RCh. RCh senktide administration resulted in …


The Effect Of Feed Manufacture Techniques On Pathogen Reduction And Feed Nutrient Value, Timothy Paul Boltz Jan 2019

The Effect Of Feed Manufacture Techniques On Pathogen Reduction And Feed Nutrient Value, Timothy Paul Boltz

Graduate Theses, Dissertations, and Problem Reports

Experiments were conducted to evaluate how differing feed manufacture techniques, such as varying conditioning times and new equipment, can affect pathogen mitigation, feed manufacture metrics, amino acid digestibility, and enzyme recovery in feed. Feed hygienics are of increasing importance in providing safe feed to animals, and ultimately safe food for consumers. Salmonella has been identified as a major microbial hazard in animal feed that has been linked to animal and human illness. In chapter 2, the effects of standard pelleting and more thermally aggressive techniques were utilized to determine pathogen mitigation potential. Use of antibiotics has decreased in recent years …