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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 …

Comprehensive Poultry Supply Chain Model With Vertical And Horizontal Linkages: Implication Of Domestic And International Shocks, Hakan Unveren

Graduate Theses and Dissertations

According to USDA FAS, in 2017, the US was the largest broiler-producing country with 18.696 million metric tons and the second largest exporter of broiler products with 3.075 million metric tons (Brazil is the largest exporter with 3.847 million metric tons). Thus, around 83% of US production is consumed domestically. According to USITC, chickens are the most important protein source in the US, and Americans consume more chicken per capita than any other country. However, while the broiler industry is a key segment of US agriculture, it is underserved by large-scale supply-chain and trade models.

In this study, to fill …

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. …

Characterization Of Microtubule Organizing Centers In The Genus Protostelium, Including Evolutionary Implications, Ethan Taylor Ozment

Graduate Theses and Dissertations

Microtubule organizing centers (MTOCs) are cellular regions of microtubule nucleation. The best known MTOCs are those associated with the centrosome, but several non-centrosomal MTOCs are known in eukaryotes, especially in land plants. MTOCs are poorly characterized across the breadth of amoebozoan diversity, but are well-known in certain amoebozoan lineages, including the genus of protosteloid slime molds Protostelium. The structure of the MTOC is known for two non-ciliated species, P. nocturnum and P. mycophaga, as well as P. aurantium, which can reversibly become ciliated under appropriate conditions. P. nocturnum and P. mycophaga have acentriolar centrosomal MTOCs while P. aurantium has a …

Painting The Leaky Pipeline Pink: Girl Branded Media And The Promotion Of Stem, Juniper Patel

Graduate Theses and Dissertations

This thesis provides a critical feminist analysis of girl branded media depictions of girls in STEM. Through close textual analysis of three case studies—Disney Fairies films, Barbie: Dreamhouse Adventures, and My Little Pony: Equestria Girls media—I found that such STEM promotion tends to emphasize traditional gender roles and neoliberal market values. Disney Fairies films promote traditional gender roles via portrayals of play STEM, white hegemony, and western beauty standards. Additionally, these films promote the neoliberal ideal of industrialization as consequence free. Dreamhouse Adventures depicts STEM in relation to traditional gender norms such as caretaking, heteronormativity, and girl culture. Furthermore, this …

Teaching Introductory Programming Concepts Through A Gesture-Based Interface, Lora Streeter

Graduate Theses and Dissertations

Computer programming is an integral part of a technology driven society, so there is a tremendous need to teach programming to a wider audience. One of the challenges in meeting this demand for programmers is that most traditional computer programming classes are targeted to university/college students with strong math backgrounds. To expand the computer programming workforce, we need to encourage a wider range of students to learn about programming.

The goal of this research is to design and implement a gesture-driven interface to teach computer programming to young and non-traditional students. We designed our user interface based on the feedback …

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 …

Black Female Graduate Students' Experiences Of Racial Microaggressions At A Southern University, Kendra Elizabeth Shoge

Graduate Theses and Dissertations

Researchers have found that microaggressions can cause psychological distress, frustration, avoidance, confusion, resentment, hopelessness, and fear. Previous studies from Southern universities have addressed the adjustment experiences of Black women in graduate programs, obstacles faced by Black women in higher education and strategies to overcome those obstacles, and factors associated with Black student motivation and achievement. Discrimination and racism are factors identified in those studies, however, there is little research on the experiences of Black women in graduate programs and the impact of racial microaggressions on them.

The purpose of this study was to examine Black female graduate students’ experiences of …

Role Of Local Renin-Angiotensin System In Potentiating Early Calcific Aortic Valve Disease, Jessica Perez

Graduate Theses and Dissertations

Angiotensin-II (Ang-II), a peptide hormone, is a potent vasoconstrictor and cell mitogen. It has been implicated in the development of hypertension as well as atherosclerosis. Recent work has shown that sclerotic aortic valves possess expression of angiotensin type I receptor (AT-1R) and angiotensin converting enzyme (ACE), suggesting altered angiotensin signaling during disease. The role of altered angiotensin signaling on aortic valve mechanics, however, is not clearly understood. We seek to understand the direct effects of the renin angiotensin signaling (RAS) system on the biological and biomechanical properties of aortic valve tissue and develop a finite constitutive model that mimics the …

The Effect Of Osmotic Stimulation Of Copeptin On Glucose Metabolism In Healthy Adults, Lisa Tjorven Jansen

Graduate Theses and Dissertations

Diabetes is currently affecting 30 million Americans. To combat disease onset, lifestyle interventions have been focused on. Low water intake, alongside elevated concentrations of circulating copeptin, has been linked to increased risk for. However, it is unknown whether this effect on glucose regulation is acute or chronic. Furthermore, no study to date assessed the effects of copeptin independent of the renin-angiotensin-aldosterone system (RAAS). Purpose: The purpose of these studies was therefore two-fold: 1) to establish high endogenous copeptin concentrations independent of RAAS, and 2) to assess glucose metabolism following a standardized oral glucose tolerance test (OGTT) during high concentrations of …

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 …

Analysis And Conservation Of Native Forests At Kessler Mountain Fayetteville, Arkansas, Alan James Edmondson

Graduate Theses and Dissertations

Kessler Mountain in Fayetteville Arkansas has long been recognized for its beauty and natural resources. Parts of Kessler Mountain have been homesteaded and developed in the past, but most of the mountain has remained relatively undisturbed. The planned development of over 4,000 housing units to cover Kessler Mountain stimulated controversy and consideration of other management alternatives. A twist of fate involving an economic recession, a dedicated group of outdoor recreation enthusiasts, and environmental conservationists led to the permanent protection of 384 acres in the Kessler Mountain Regional Park. To help evaluate the natural resources at Kessler Mountain, forest composition, structure, …

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 …

Monstrous Mobility In Dr. Jekyll And Mr. Hyde And Dracula, Autumn Danielle Weese

Graduate Theses and Dissertations

This thesis explores Late Victorian Gothic texts that are central to theories on monstrosity in terms of mobility by examining Dr. Jekyll and Mr. Hyde and Dracula. The goal of this project is to survey the ways in which two exemplary monsters, Mr. Hyde and Count Dracula, promote mobility for others and themselves as an inherent part of their monstrosity. The variety of this mobility is demonstrated by examples showing how monsters move and encourage movement in ways that are social and transformative as well as physical. Because social mobility is essential to these movements, this study also considers the …

Synchrophasor-Based Fault Location Detection And Classification, In Power Systems, Using Artificial Intelligence, Hemal Falak

Graduate Theses and Dissertations

With the introduction of sophisticated electronic gadgets which cannot sustain interruption in the provision of electricity, the need to supply uninterrupted and reliable power supply, to the consumers, has become a crucial factor in the present-day world. Therefore, it is customary to correctly identify fault locations in an electrical power network, in order to rectify faults and restore power supply in the minimum possible time. Many automated fault location detection algorithms have been proposed, however, prior art requires topological and physical information of the electrical power network. This thesis presents a new method of detecting fault locations, in transmission as …

Molecular Basis Of Pathogenesis And Host Determination In Cercospora Sojina: From Phenotypic To Genotypic Patterns, Wagner Calegari Fagundes

Graduate Theses and Dissertations

Frogeye leaf spot (FLS), caused by Cercospora sojina, is an important and recurrent disease of soybean in many production regions. Genetic resistance is potentially one of the most cost-effective and sustainable strategies to control FLS. However, C. sojina has already demonstrated the ability to overcome resistance conveyed by single R-genes (resistance genes) of soybeans, followed by the emergence of new physiological races. Although understanding population genomics and the virulence gene inventories in fungal plant pathogens is extremely important to improve disease control measures, studies regarding host specificity and pathogenesis in C. sojina are very limited. Therefore, the overarching goal of …

Interfacial Tailoring Of Lithium-Ion Batteries By Atomic/Molecular Layer Deposition, Qian Sun

Graduate Theses and Dissertations

Lithium-ion batteries (LIBs) are promising energy storage devices, which play significant roles in addressing problems related to fossil fuels depletion and environmental pollution. Since the 1990s, LIBs have attracted great attention for many applications. Nowadays, LIBs are dominating portable electronics, having several advantages over their forerunners, such as high voltage (3.3~4.2 V) [1,2], low self-discharge (< 5~10 %/month) [3,4], wide operation temperature (-20~60 °C) [5,6], and fast charge/discharge rate [7,8]. However, LIBs deliver an energy density of 100-220 Wh/kg in practice to date, which is far from their theoretical ones, thus hindering their further applications in electric vehicles. Additionally, LIBs have been plagued by other problems, such as intolerance to overcharge/overdischarge, low heat resistance, lithium dendrites growth, large volume change of the silicon anode, large polarization and even safety problems.

Atomic layer deposition (ALD) and molecular layer deposition (MLD) are two important techniques, both proceeding in self-limiting gas-solid reactions and exhibiting excellent capabilities for ultra-thin films, conformal coatings, and controllable growth. They can be employed to address the problems of LIBs mentioned above by …

A Generative Statistical Approach For Data Classification In A Biologically Inspired Design Tool, Marvin Manuel Arroyo Rujano

Graduate Theses and Dissertations

The objective of the research this thesis describes is to find a way to classify text-based descriptions of biological adaption to support Biologically Inspired design. Biologically inspired design is a fairly new field with ongoing research. There are different tools to assist designers and biologists in bio-inspired design. Some of the most common are BioTRIZ and AskNature. In recent years, more tools have been proposed to aid and make research in the field easier, for example, the Biologically Inspired Adaptive System Design (BIASD) tool. This tool was designed with the goal of helping designers in early design stages generate more …

Epidemiological Studies Of Soybean Vein Necrosis Virus And Potential Resistance Mechanisms To Its Vector Neohydatothrips Variabilis (Beach), Jing Zhou

Graduate Theses and Dissertations

Soybean (Glycine max (L.) Merrill) is one the most important crops in global agriculture with annual production of over 260 million metric tons. As the dependence of a growing global population to soybean has increased, so does the importance of soybean diseases and pests. Over 200 pathogens attack soybean; among them, viruses pose a major threat to the soybean industries accounting for approximately 10% of the annual yield reduction caused by diseases in the past two decades. Soybean vein necrosis virus (SVNV) is a relatively newly discovered virus causing the homonymous disease. The widespread occurrence of the disease in major …

Physiological Characterization Of The Soynam Parental Lines Under Field Conditions, Akshita Mishra

Graduate Theses and Dissertations

The narrow genetic pool of soybean (Glycine max L. Merr.) in North America can limit its future yield gains. Among the worldwide germplasm collection of 45,000 unique landraces, only 80 contribute 99% to the collective parentage of North American soybean cultivars. Among these 80 landraces, just 17 contribute to 86% of the collective parentage of the modern cultivars. The Soybean Nested Association Mapping population (SoyNAM) was therefore developed with the objective of diversifying the soybean gene pool. Forty diverse soybean genotypes from maturity groups (MG) 1 through 5 were crossed with a common MG 3 parent to develop 40 recombinant …

Evaluation Of Genetic And Environmental Influences On Broiler Meat Quality, Sara Katherine Orlowski

Graduate Theses and Dissertations

The effect of both genetic and environmental influences on broiler meat quality were evaluated over three experiments. Selection response was assessed for broiler lines selected for high (HBY4) and low (LBY4) four day percentage breast yield which were formed from a random bred control (RAN). A modern random bred population (MRB) created in 2015 was evaluated for differences in 4 day percentage breast yield and the resulting differences in the incidence and severity of the woody breast and white striping myopathies. Additionally, the use of embryonic thermal manipulation to impact cell division and early caloric feed restriction to slow growth …

Vegetation Characteristics And Bird Communities Associated With Singing Painted Buntings In Northwest Arkansas, Lauren Kristina Thead

Graduate Theses and Dissertations

It has been shown that bird communities are affected by the species composition and physical structure of plant communities. Within avian communities, the bird species that are the most localized in distribution tend to be the most affected by habitat changes. My research analyzed plant and bird communities found with the Painted Bunting (Passerina ciris Linnaeus), a locally common but declining species throughout much of its range. First, I describe vegetation characteristics associated with singing male Painted Buntings in northwest Arkansas. I categorized field sites with singing male Painted Buntings as either managed for wildlife or unmanaged, based on land-use …

Burning Community Integration And Disability, Christopher Shane Brace

Graduate Theses and Dissertations

Individuals with anxiety and depression have always been marginalized and stigmatized. Individuals with “hidden” disabilities are encouraged by society to keep them hidden, or face ridicule and persecution. Society decreases their sense of self-worth, and self-efficacy by destroying any perception of normalcy. Social support resources are vital for individuals with anxiety and depression’s continued mental health. As time goes on the individuals experience a decrease in the amount of available resources, at the same time the need for them increases. These individuals need a way to quickly replenish their social resources and the Burning Man regional network creates a unique …

Weed Control And Management For Vegetable Soybeans In Arkansas, Seth Bernard Abugho

Graduate Theses and Dissertations

Vegetable soybean [Glycine max (L.) Merr.], known as edamame, needs weed management tools. Releasing locally adapted edamame soybean varieties and registering herbicides are necessary for successful production and expanding the edamame industry. This research aimed to 1) identify herbicides labeled for grain soybean for potential use on edamame; 2) evaluate differential tolerance of edamame soybean varieties to selected grain soybean herbicides; and 3) identify a feasible edamame-based crop rotation system. For objective 1, 26 herbicide treatments were tested on AVS-4002 edamame including preplant (PPL), preemergence (PRE) and postemergence (POST) herbicides labeled for grain soybean. Preplant herbicides caused 9 to 28% …

Microbiota Metabolic Product Deoxycholic Acid Prevents Campylobacter Jejuni Chicken Colonization Through Modulating Ceca Anaerobes, Bilal Ali Alrubaye

Graduate Theses and Dissertations

Campylobacter jejuni is a prevalent infectious enteritis mainly foodborne from chickens. Despite of reducing C. jejuni food contamination dramatically decreases campylobacteriosis, few effective approaches are available for the bacterial reduction in chickens. The aim of this study was to use microbial metabolic product deoxycholic acid (DCA) to reduce C. jejuni chicken colonization. Broiler chicks were fed 0 or 1.5 g/kg DCA, lithocholic acid (LCA), or urodeoxycholic acid (UDCA) in diets or orally gavaged with cholic acid (CA, 1.5g/kg body weight). Birds were also transplanted with DCA modulated anaerobes (DCA-Anearo) or aerobes (DCA-Aero). Birds were infected with 109 CFU/bird human clinical …

Aqueous Ozone Inactivation Of Viruses And Bacteria On Biotic And Abiotic Surfaces, Cailin Dawley

Graduate Theses and Dissertations

Produce is susceptible to contamination by foodborne pathogens. Food service establishments utilize sanitizing agents to reduce microbes on produce surfaces. The research objectives were to evaluate the efficacy of aqueous ozone 1) on the inactivation of viruses and bacteria on produce; 2) on the inactivation of viruses on stainless steel; and 3) against viruses in association with bacteria on produce surfaces. For objective 1, Boston bibb lettuce and cherry tomatoes were spot inoculated with a cocktail of viruses (murine norovirus (MNV) and MS2 bacteriophage) or bacteria (Enterobacter cloacae and Bacillus cereus) and washed for 40 min with samples taken every …

Risky Business: Millennials’ Protection Motivation Factors For Norovirus Outbreaks On College Campuses, Dylan Conrad Martinez

Graduate Theses and Dissertations

The risk and severity of hNoV transmission is obscurely recognized to foodservice millennial customers. Most commonly associated with cruise ships, consumers are not aware of its full potential to strike at other locations, especially college campuses. For the foodservice industry and the university community, it is imperative that a proactive method for increasing millennials’ motivation to practice mitigation methods emerges to reduce future hNoV outbreaks on college campuses. Research has shown that students can play a major role in the spread of hNoV on college campuses. Therefore, the purpose of these studies is to examine motivations for health protective behaviors …

Responsiveness Of Cobb Mv × 700 Broilers To Dietary Amino Acid And Energy Density, Craig William Maynard

Graduate Theses and Dissertations

As new broiler crosses are introduced to the industry, it is of paramount importance to understand their nutritional digressions from previous and other modern broilers. In particular, amino acids (AA) and dietary energy have been identified as key drivers of live performance and carcass composition. In addition, increased nutrient density in broiler diets have been linked to an increase in breast muscle myopathies such as white striping and woody breast. Therefore, a series of trials were conducted to determine the responsiveness of live performance, carcass characteristics, and breast muscle myopathies of Cobb MV × 700 broilers to dietary AA and …

Fall Migration And Winter Habitat Use Of Northern Saw-Whet Owls (Aegolius Acadicus) In The Ozark Highlands, Mitchell L. Pruitt

Graduate Theses and Dissertations

Studying movement ecology is important not only in understanding the distribution of a species, but in understanding the magnitude of migration through certain regions, as well as explaining regional differences in demographics. The Northern Saw-whet Owl (Aegolius acadicus) is a small, migratory forest owl found throughout much of North America. Despite being captured widely during fall migration, the species’ movement ecology is poorly understood. Exploratory studies outside the saw-whet owl’s normal range have successfully captured the species during fall migration. In the Ozark Highlands ecoregion of the central United States, their status has been considered vagrant during fall and winter. …

Effect Of Macrograzers (Campostoma Spp. And Faxonius Spp.) On Periphyton In Ozark Streams With Considerations Given To Macrograzer Biomass, Phosphorus, And Season: Mensurative And Manipulative Studies, Kayla R. Sayre

Graduate Theses and Dissertations

Nutrient and benthic algal biomass relationships can guide numeric nutrient criteria development in lotic systems. However, herbivorous macrograzers may confound this relationship by reducing the slope of the positive relationship between nutrients and periphyton biomass in streams. I conducted a mensurative field study to determine if stoneroller and crayfish abundance related to algal biomass at varying nutrient concentrations and manipulated macrograzer presence with electrical exclosures in streams to examine macrograzer effects on algal biomass and understand whether these effects on periphyton varied with total phosphorus (TP) or season. Macrograzer density was quantified across a TP gradient (n=15 streams; range = …