Life Sciences Commons^™

The Impacts Of Administering Metabolites Of Saccharomyces Cerevisiae On Broiler Performance, Yields And Salmonella Content Of Component Portions, Bill Douglas Potter

Graduate Theses and Dissertations

The impacts of using health-promoting Saccharomyces cerevisiae fermentation metabolites in poultry production and processing can be measured in respect to multiple measures of success. Traditionally this yeast-based compound has been administered to poultry, livestock, poultry, and other species to improve animal performance and production volume output. In addition, Saccharomyces cerevisiae fermentation metabolites have also been shown in more recent research to reduce colonization of pathogenic bacteria in the host organism’s gastro-intestinal tract. In this dissertation, the impacts of administering a functional ingredient containing Saccharomyces cerevisiae metabolites on broiler performance measures and pathogen reduction were measured. One of the studies in …

Reducing The Risk: Psychological And Technological Approaches For Improving Handwashing Practices In The Foodservice Industry, Jeffrey Allan Clark

Graduate Theses and Dissertations

As Americans are spending greater portions of their dollar on food consumed outside the home, the foodservice industry plays more of an integral part of daily existence compared to previous generations. Given the numerous annual foodborne illness outbreaks that threaten human lives while undermining confidence in the food supply, food safety is a pertinent issue for industry stakeholders, government regulators, and consumers. Food worker handwashing reduces the risk of foodborne illness transmission, yet compliance with this simple behavior is a complex problem. This dissertation addresses, predominantly, the issue of sub-optimal handwashing practices through applying psychology and technology, including wearable computers …

Phylogenomics And Geometric Morphometrics Define Species Flocks Of Snowtrout (Teleostei: Schizothorax) In The Central Himalayas, Binod Regmi

Graduate Theses and Dissertations

Schizothorax (Snowtrout) is a genus of medium-sized minnows (Cypriniformes) inhabiting glacier-fed streams, rivers, and lakes in the Himalayas. There are more than 30 species of Schizothorax across the region. The speciation and diversity of the Snowtrout in the vast hinterlands of the Himalayan Region has not been fully explored. Three species in Lake Rara, Western Nepal are considered a species flock, comprising endemic ecotypes that are morphologically differentiated and reproductively isolated.

My dissertation research examined the diversity of Schizothorax in the Central Himalayan region and evolutionary relationships among species distributed in the Tibet, Central and Southeast Asia. Chapter I describes …

Spatial Reorganization Of Histone-Like Nucleoid Structuring Proteins Caused By Silver Nanoparticles, Meaad Alqahtany

Graduate Theses and Dissertations

Silver nanoparticles (AgNPs) and ions (Ag+) can be the new generation of antibiotics due to their antimicrobial effects against bacteria and other microbes. Many studies have shown that AgNPs and suppress the growth of bacteria and damage the cell walls of the microbes; therefore, treating bacterial cells with AgNPs may be a promising method to terminate multi-resistant bacteria. In this work, the effect of AgNPs with two different surface coatings on the spatial reorganization of histone-like nucleoid structuring (H-NS) proteins in Escherichia coli bacteria was investigated using quantitative super-resolution fluorescence microscopy to understand the toxicity and antimicrobial mechanism of AgNPs. …

Hormone Signaling, Gene Expression, And Mitochondrial Hormone Receptor Expression In Avian Muscle (Cells), Kentu Rushadd Lassiter

Graduate Theses and Dissertations

Mitochondria are vital to the proper growth and function of muscle cells since they’re responsible for the majority of ATP production used for cellular energy. Previous studies have investigated how differences in mitochondrial function affects feed efficiency (FE) in broilers phenotyped for High and Low FE. Low FE broilers have been shown to have increased levels of reactive oxygen species (ROS), thus contributing to higher levels of oxidative stress and damage seen in these birds. Global gene and protein expression studies conducted on breast muscle of the High FE and Low FE phenotypes have suggested that differences in mitochondrial function …

The Evaluation Of Low-Use-Rate Zinc Fertilization Strategies On Seedling Canopy Coverage, Zn Concentration, Biomass, And Grain Yield, Maxwell David Coffin

Graduate Theses and Dissertations

Zinc (Zn) is the most common micronutrient deficiency in flooded rice (Oryza sativa L.). Some new Zn fertilization methods have been advertised, but have limited research supporting their efficacy. This study mainly compared the effect of Zn-seed treatment rate in combination with other low-use-rate Zn-fertilization methods to the standard of 11 kg Zn ha-1 as ZnSO4 on rice early-season canopy cover, tissue-Zn concentration, and grain yield. A secondary objective evaluated an alternative method (to seed treatment with ZnO) of enhancing seed-Zn concentration using post-heading foliar-Zn application on seedling tissue-Zn concentration and grain yield. For the main objective, rice seed was …

The Impact Of Fall Armyworm, Spodoptera Frugiperda (J.E. Smith), Feeding And Mechanical Defoliation On Growth And Yield Of Rice, Oryza Sativa (L.), Layton Denman Mccullars

Graduate Theses and Dissertations

The fall armyworm, Spodoptera frugiperda (J.E. Smith), (FAW) is a serious pests of many crops, and can be observed feeding throughout the entire growing season on rice, Oryza sativa, (L.). A new defoliation based threshold would help rice growers and consultants make more economically sound decisions for FAW. Work from this thesis focuses on determining the amount of damage caused by FAW feeding at different growth stages and effective insecticide seed treatments for controlling this pest.

Field plots were mechanically defoliated to determine grain yield loss across multiple growth stages and defoliation percentages. Results indicated that defoliation in late vegetative …

A Phenomenological Study Of The Lived Experiences Of Counseling Students In A Co-Facilitated Experiential Group, Alexandra Meyers

Graduate Theses and Dissertations

Research in the fields of experiential learning, group psychotherapy, and neuroscience has supported the inclusion of the experiential group in counseling training programs due to the potential for positive impact on students’ personal and professional development (Badenoch & Cox, 2010; Denninger, 2010). Investigations exploring counseling students’ experiences of the experiential group have been primarily limited to quantitative studies, while in-depth qualitative inquiry has been minimal. Additionally, an extensive review of the literature has found there have been no qualitative studies examining experiential groups co-facilitated by a course instructor and a doctoral student. The purpose of this phenomenological study was to …

A Silicon Germanium Cmos Linear Voltage Regulator For Wireless Agricultural Applications, Aminta Naidili Castillo Robles

Graduate Theses and Dissertations

This thesis presents the design, simulation and test results of a silicon germanium (SiGe) complementary metal-oxide-semiconductor (CMOS) linear regulator. The objective of the circuit is to power other analog devices regardless of the load current and input voltage changes. The application of this regulator is to be part of a project developing a miniaturized semiconductor platform that can be inserted into stems of crops in order to measure data inside the plant and then send it wirelessly to the user. The linear regulator was designed on a BiCMOS SiGe 0.13µm which is a GlobalFoundries process. It has been tested at …

Targeting Sec61Α By Ipomoeassin F Leads To Highly Cytotoxic Effect, Zhijian Hu

Graduate Theses and Dissertations

Ipomoeassin F is a flagship congener of a resin glycoside family that inhibits growth of many tumor cell lines with only single-digital nanomolar IC50 values. However, biological and pharmacological mechanisms of ipomoeassin F have been undefined. To facilitate exploration of the biological and pharmacological properties, we performed sophisticate SAR (Structure–activity relationship) studies of ipomoeassin F to understand its pharmacophore and structure properties so that we can design favorable probes for further biological investigation. By applying appropriate deviates that possess fluorescent groups and similar bio-activity, the target protein was found to be localized in endoplasmic reticulum (ER). Through biotin affinity pull …

Using Cover Crops To Recycle Nutrients In An Arkansas No-Till Corn System, Kelsey Lynn Hoegenauer

Graduate Theses and Dissertations

Cover crops can provide many benefits to cropping systems including erosion control, weed suppression, and increased soil organic matter. Regardless of the intended goal for using cover crops, the changes to the nutrient flux in a cropping system caused by cover crops retaining and recycling nutrients needs to be considered in order to maximize the productivity of the following commodity crops. This research encompassed complementary greenhouse, field, and laboratory experiments to evaluate nutrient uptake and release by tillage radish (Raphanus sativus) and cereal rye (Secale cereale) cover crops, as well as the subsequent early-season recovery of recycled nutrients by the …

Diffuse Reflectance Spectroscopy To Quantify In Vivo Tissue Optical Properties: Applications In Human Epithelium And Subcutaneous Murine Colon Cancer, Gage Joseph Greening

Graduate Theses and Dissertations

Colorectal cancer is the 4th most common and 2nd deadliest cancer. Problems exist with predicting which patients will respond best to certain therapy regimens. Diffuse reflectance spectroscopy has been suggested as a candidate to optically monitor a patient’s early response to therapy and has been received favorably in experimentally managing other cancers such as breast and skin. In this dissertation, two diffuse reflectance spectroscopy probes were designed: one with a combined high-resolution microendoscopy modality, and one that was optimized for acquiring data from subcutaneous murine tumors. For both probes, percent errors for estimating tissue optical properties (reduced scattering coefficient and …

Evaluation Of Herd Size Management Strategies, Colson A. Tester

Graduate Theses and Dissertations

This thesis is comprised of two studies examining the effects of price signal based herd size management strategies on profitability of cow-calf operations. Herd size management strategies were evaluated across the previous two cattle cycles, 1990-2014, using a fixed land resource and included a variety of production scenarios. These scenarios varied in terms of stocking rates, fertilizer applications rates, and calving season. Each scenario was also analyzed both with and without weather effects on forage production. Weather effects were simulated using a production index derived from satellite imagery across the observed 25-year period. Three herd size management strategies: i) constant …

Development And Evaluation Of Selected Chemoprophylaxis Candidates And A Candidate Live-Attenuated Vaccine For Prevention Of Histomoniasis In Turkeys, Lesleigh Beer

Graduate Theses and Dissertations

Histomoniasis, commonly known as blackhead disease, has increased in prevalence due to the regulatory ban of prophylactics and therapeutics within the past 30 years. The objective of this thesis was to evaluate the efficacy of selected dietary chemoprophylaxis candidates as well as an in vitro live-attenuated vaccine candidate Histomonas meleagridis for prevention of histomoniasis. Chapter one addresses deoxycholic acid and a biliogenic diet intended to endogenously increase production of this secondary bile acid. Deoxycholic acid was effective in vitro but failed to prevent histomoniasis when evaluated during the in vivo experimental disease trial with turkeys. The biliogenic diet did not …

Evaluation Of Crop Tolerance And Weed Control In Corn And Grain Sorghum With Atrazine Replacements, Jacob Thomas Richburg

Graduate Theses and Dissertations

Atrazine is a foundational herbicide for weed control in both corn (Zea mays L.) and grain sorghum [Sorghum bicolor (L.) Moench] production. However, studies have shown that while atrazine may be an effective herbicide for preemergence and postemergence control of weeds, it also has risks. The low Koc of atrazine as well as its extensive use over the past 50 years have led it to become the most common groundwater contaminant near agricultural soils. Given these findings, atrazine has faced severe scrutiny while under consideration for reregistration. In the event that atrazine is not reregistered, corn and grain sorghum producers …

Biogeography Of Endemic Dragonflies Of The Ozark-Ouachita Interior Highlands, Wade Alexander Boys

Graduate Theses and Dissertations

A common pattern across many taxonomic groups is that relatively few species are widespread while the majority are restricted in their geographic ranges. Such species distributions are used to inform conservation status, which poses unique challenges for rare or cryptic species. Further, priority status is often designated within geopolitical boundaries, which may include only a portion of a species range. This, coupled with lack of distributional data, has resulted in species being designated as apparently rare throughout some portions of their range, which may not accurately reflect their overall conservation need. The Interior Highlands region of the central United States …

Comparative Plasma Proteomics In Muscle Atrophy Induced By Cancer Cachexia And Hindlimb Unloading, Kirsten Rene Dunlap

Graduate Theses and Dissertations

Introduction: Muscle atrophy results from a dysfunction in protein turnover that leads to loss of mass and function and occurs concurrently with multiple pathologies such as cancer and extended bed rest. Atrophy reduces overall quality of life while increasing morbidity and mortality. Currently, efficacious therapeutic interventions to treat and prevent muscle wasting in all its forms are lacking, however if conserved mechanisms can be identified between wasting conditions, this would aid in the development of multipurpose therapeutics to ameliorate this pathology. Purpose: To examine circulating factors present across atrophic pathologies. Methods: 35 male C57BL/6J mice were assigned to hindlimb unloading …

Optimization Of The Light Environment For Broiler Chickens, Douglas J. Aldridge

Graduate Theses and Dissertations

The use of artificial light sources has been necessitated by the use of fully enclosed rearing facilities for improved environmental control. Light Emitting Diodes (LED) have been developed as a light source that reduce the utilities required to provide equal light to that of incandescent sources. The following reports were carried out to investigate the effects of two light color temperatures, light intensity and light intensity gradients on broiler chicken production and behavior. The first investigation consisting of two consecutive trials investigated the effect of two light color temperatures (2700 K and 5000 K) in addition to the preference for …

Daily To Seasonal Moisture Signals Present In Sub-Annual Tree-Ring Data, Ian Howard

Graduate Theses and Dissertations

In recent decades, there has been an increase in the development of sub-annual earlywood (EW) and latewood (LW) width tree-ring chronologies that have been used to make long-term inferences about discrete seasonal moisture variability for different regions of North America. This doctoral research developed a new network of EW, LW, and adjusted latewood (LWa) tree-ring chronologies from the western Great Plains. These chronologies were used to reconstruct 300+ years of spring and summer moisture variability over the northern and southern Plains. The reconstructions document new information about the long-term seasonal climate history of the Great Plains, including the unusual nature …

Amphibian And Reptile Community Responses To Forest And Riparian Disturbance, Jacquelyn Christine Guzy

Graduate Theses and Dissertations

Riparian zones are transitional, semi-terrestrial areas regularly influenced by freshwater. These areas serve as dispersal corridors for many animal and plant species and ultimately function as important reservoirs of biodiversity in altered landscapes. While much of the riparian habitat in the United States has been affected by anthropogenic activities, management actions may mitigate potentially negative influences of these activities. For example, Streamside Management Zones (i.e., riparian buffers; SMZs) are commonly implemented within managed forests to protect water quality, but may also provide habitat for riparian-associated wildlife. Yet, little research has rigorously addressed the value of SMZs for wildlife, particularly cryptic …

Interactions Between The Protein Industry And Blogs: An Analysis Of Content And Perceptions, Kylie Hackworth

Graduate Theses and Dissertations

This thesis contains two articles that describe and characterize the use of the social media platform of blogging in the context of the animal agriculture and protein industry. The first article used content analysis to analyze blog posts and look for themes throughout the posts. This study included 37 posts from ten authors and resulted in four recurrent themes. The major themes were environment, consumption of protein, alternative protein source, and alternative dieting. The tones regarding these themes were both negative and positive toward the protein industry.

The second article used hand-coding to look for themes and similarities concerning flow …

Do Enallagma Exsulans From Streams And Lakes Show Patterns Of Divergence?, Savannah Rae Graham

Graduate Theses and Dissertations

Divergent selection across heterogenous environments could lead to adaptive divergence in populations resulting in potential local adaption. These populations have phenotypic differences that are fitness related and make native individuals more fit than non-native individuals. My research focuses on a species of damselfly, Enallagma exsulans, to explore local adaptation and morphological differences as a result of divergent selection or plasticity. My first study explored potential local adaptation of wild caught stream and lake E. exsulans using a reciprocal transplant design, a classic approach for this objective. The stream and lake sites chosen were on a small spatial scale allowing for …

The Farmers’ Federation: Regional Racial Mythologies As Agricultural Capital, Jama Mcmurtery Grove

Graduate Theses and Dissertations

In 1927, the Farmers’ Federation agricultural cooperative in Western North Carolina launched an organization to solicit funds from wealthy donors. The money raised through philanthropic campaigns enabled the cooperative to fund large-scale agricultural projects, which helped members navigate the dramatic agricultural transformations of the early twentieth century. Although the cooperative advocated a progressive program of business-minded, scientific farming, its leadership modified programs to reflect farmer members’ limited resources and the realities of mountain production. As a result, the co-op provided a crucial bridge between white farmers and new methods of agricultural production that reached deep into peoples’ familial and productive …

Broiler Breeder Amino Acid Levels And Progeny Nutritional Status, Leasea Butler

Graduate Theses and Dissertations

Crude protein needs of chickens have changed due to genetic line differences and selection of those lines for differing broiler traits. Standard commercial broiler strains have been selected to be used to meet multiple processing categories typically at live body weights less than 3.5 kg. In the last two decades high-yielding broiler strains were introduced into the commercial market. These breeds are known as the Cobb 700 and Ross 708. The works included within are focused on the Cobb 700 high-yielding broiler strain, and its response to crude protein, with emphasis on digestible lysine.

Electrophysiological Correlates Of Visual Object Category Formation In A Prototype-Distortion Task, Stephanie Marie Long

Graduate Theses and Dissertations

In perceptual learning studies, participants engage in extensive training in the discrimination of visual stimuli in order to modulate perceptual performance. Much of the literature in perceptual learning has looked at the induction of the reorganization of low-level representations in V1. However, much remains to be understood about the mechanisms behind how the adult brain (an expert in visual object categorization) extracts high-level visual objects from the environment and categorically represents them in the cortical visual hierarchy. Here, I used event-related potentials (ERPs) to investigate the neural mechanisms involved in object representation formation during a hybrid visual search and prototype …

A Hidden Markov Factor Analysis Framework For Seizure Detection In Epilepsy Patients, Mahboubeh Madadi

Graduate Theses and Dissertations

Approximately 1% of the world population suffers from epilepsy. Continuous long-term electroencephalographic (EEG) monitoring is the gold-standard for recording epileptic seizures and assisting in the diagnosis and treatment of patients with epilepsy. Detection of seizure from the recorded EEG is a laborious, time consuming and expensive task. In this study, we propose an automated seizure detection framework to assist electroencephalographers and physicians with identification of seizures in recorded EEG signals. In addition, an automated seizure detection algorithm can be used for treatment through automatic intervention during the seizure activity and on time triggering of the injection of a radiotracer to …

Validity And Reliability Of A 5-Minute Web-Camera Based Eye Tracking Test To Assess Visual Memory And Cognition, Emily Bates

Graduate Theses and Dissertations

There are approximately 5.7 million Americans currently living with Alzheimer’s Disease (AD). Early detection of cognitive impairment allows for earlier treatment, potentially slowing or halting cognitive decline. A 30-min web-camera eye tracking assessment (30-min VPC) has been validated as a tool to predict AD risk. However, a shorter version would allow for greater scalability and improve user experience. The purpose of this study was to: 1) determine the validity of the 5-minute web-camera based VPC test with the 30-min test, 2) determine the test-retest reliability of the 5-min test, 3) compare the 5-minute test scores of cognitively intact adults (18-39 …

Understanding The Molecular Strategies Of Campylobacter Jejuni For Survival In Amoeba And Chicken., Deepti Pranay Samarth

Graduate Theses and Dissertations

Campylobacter jejuni endure to be major cause of gastroenteritis in humans worldwide. C. jejuni is fastidious in laboratory setup but can cause waterborne infection through contaminated water where none of these fastidious conditions are met. This dissertation presents an assortment of studies focused in reviewing three major factors which could present a helping hand to C. jejuni in its environmental survival viz. i) association with free-living amoebae (FLA) ii) horizontal gene transfer (HGT) contributing towards its genetic diversity iii). Viable but non-culturable (VBNC) state.

Acanthamoeba is a FLA linked to environmental survival of many intracellular pathogens, including C. jejuni. In …

Validation Of A 5-Minute Vpc Test To Assess And Compare Cognitively Intact Individuals And Individuals With Cognitive Impairments, Spencer Smith

Graduate Theses and Dissertations

The prevalence of cognitive impairments in the older adult population is growing. Finding treatment solutions to impede a cognitive decline can possibly lead to fewer cases of mild cognitive impairment, dementia, and Alzheimer’s disease. A Visual Paired Comparison (VPC) could serve as a tool to predict, monitor, and regulate people who are susceptible to a cognitive decline. The purpose of this study was to 1) to determine the validity of the Neurotrack 5-minute VPC test with the Neurotrack 30-minute VPC test, 2) to determine the test-retest reliability of the Neurotrack 5-minute VPC test, 3) to compare Neurotrack 5-minute VPC scores …