Digital Commons Network^™

Moulins: Down The Arctic Drain, Jonathon Nugent Carlson

Graduate Theses and Dissertations

This observation-style nonfiction documentary film follows a National Science Foundation expedition to the Greenland ice sheet. The bivouac lasted for 25 continuous days. University of Arkansas Professor of Geosciences Matt Covington, Ph.D. teamed up with University of South Florida Professor Jason Gulley, Ph.D. to plan, propose, and ultimately accomplish the research goals of the expedition with the assistance of Ph.D. student Celia Trunz, M.S., and experienced expeditionary team member Vickie Siegel. As an observational-style documentary film, all scientific background information imparted herein is taken directly from interviews conducted with Professor Covington, to minimize opining.

The film begins in mid-flight, as …

Novel Methodology For Emboli Analog Production And In-Vitro Simulation Of Acute Ischemic Stroke, Anne Preut

Graduate Theses and Dissertations

Stroke is the leading cause of disability and a primary cause of mortality, resulting in an estimated $33 billion dollars spent on healthcare, rehabilitation and lost productivity in the United States each year. The most prevalent cause of stroke incidents are acute ischemic events, manifested as blood clots in the vasculature supplying the brain. Current gold standard treatments have improved since 2006 with the introduction of mechanical stent retrievers; however, several issues with the current treatments to acute ischemic stroke remain. Thrombolysis of the clot with a tissue plasminogen activator may lead to weakening the vessel wall and consequently, hemorrhaging. …

Decisions Set In Stone: Spatial Analyses Of Ozark Rock Art Sites, Elements, And Motifs With Gis, Jordan Lee Schaefer

Graduate Theses and Dissertations

This thesis uses Geographic Information Systems (GIS) to spatially analyze rock art distributions in the Salem Plateau section of the Arkansas Ozarks. Statistical tests, such as chi-square and t-testing, are applied to provide an objective view of rock art patterning in relation to the overall landscape. The data collected from these methods allow one to discern the locational preferences for rock art, which potentially reveal cultural details about the people involved with its creation. Multiple analytical perspectives are applied throughout, initially focusing on comparisons with expected values and random points. Later statistical tests use bluff shelter distributions as reference data …

Pre-Season Vitamin D And Iron Levels As A Predictor Of Musculoskeletal Injury In Division I Athletes, Mariellen Katherine Veach

Graduate Theses and Dissertations

Context: Pre-season testing that includes the analysis of micronutrient serum levels in the blood has become a routine part of pre-participation examinations in collegiate football. Objective: Assess the predictability of vitamin D and iron serum levels as indicators of future injury during a subsequent competitive season for lower extremity sprains, strains, and fractures. Additionally, determine the effectiveness of vitamin D supplementation on increasing serum 25(OH)D levels and preventing injury. Design: Cohort Study. Setting: National Collegiate Athletic Association Division I football program. Participants: Football athletes (n=349) who underwent pre-participation examinations and participated in at least one of three competitive football seasons. …

I, Myself, And Me, The Human Being, David Manuel Cajias

Graduate Theses and Dissertations

In this project are advanced two ways of seeing the ordinary human being with the aim of understanding who he is: namely, from the perspective of his personal identity and from the point of view of his self-conception. The chapters included in the first part are meant to treat the issue of personal identity from a practical perspective, whereas the ones included in the second part intend to assess the utility of self-conception from a phenomenological standpoint. Ultimately, I bring together these two perspectives into a unitary understanding of the human being in the context of his everyday life.

Characterization Of Bacteriorhodopsin And Halorhodopsin Reconstituted In Lipid Bilayer Membranes, Joel Domkam Kamwa

Graduate Theses and Dissertations

Motivated to produce electricity with photon activated ion pumps, the main purpose of this work was to characterize the photosynthetic membrane proteins bacteriorhodopsin (proton pump) and halorhodopsin (chloride pump). The proteins were re-suspended in lipid bilayers. For this work, an experimental set-up was built which included: chambers for lipid bilayer formation and characterization, lasers for ion pump activation, and an AxoPatch electrophysiology system for small photocurrent measurement. Lipid bilayer membranes were formed using mostly folding method: folding two monolayers together. The membranes were characterized by their resistance, capacitance, and generated photocurrent. Photocurrent was generated upon illumination of lipid-protein membranes with …

Mitochondrial Mrna Translation Is Required For Maintenance Of Oxidative Capacity, David Lee

Graduate Theses and Dissertations

Oxidative metabolism is required to produce adequate energy to sustain human life. A primary example of deteriorating oxidative capacity is seen in the cardiac musculature during chronic heart failure. This suggests that by improving oxidative potential, chronic heart disease could be mitigated and one approach to accomplish this may be through targeting the mt-mRNA translation system. Purpose: This investigation’s purpose was to characterize disruptions in mt-mRNA translation machinery in multiple forms of cardiomyopathy and to determine if mitochondrial mRNA translation initiation factor (mtIF2) is necessary to maintain oxidative capacity in cardiomyocytes. Methods Using a combination of animal and cell culture …

A Genome Wide Association Study For Fusarium Head Blight Resistance In Southern Soft Red Winter Wheat, Amanda Holder

Graduate Theses and Dissertations

Fusarium head blight (FHB) is a disease of small grains caused by the fungal pathogen Fusarium graminearum. FHB poses potential economic losses and health risks due to the accumulation of the mycotoxin deoxynivalenol (DON) on infected seed heads. The objectives of this study are: 1) evaluate soft red winter wheat (SRWW) lines for resistance to FHB in terms of resistance to initial inoculum (incidence); resistance to spread within the head (severity); resistance to DON accumulation; and resistance to Fusarium damaged kernels (FDK), 2) determine the frequency and effect of known FHB resistance genes and quantitative trait loci (QTL), and 3) …

Evaluation Of Water Resources And Hydraulic Influences In The Restoration Of The Western Part Of The Mesopotamian Marshlands, Ali Kareem Al-Quraishi

Graduate Theses and Dissertations

The purpose of this study is to assess the water resources and water conveyance system of the western part of the Mesopotamian marshes (Al-Hammar marsh) as well as develop a water conveyance system to distribute water throughout the western Al-Hammar marsh. These processes are significant to identify the current restoration problems and help to create restoration strategies for the marsh. Also, proper management strategy to the Al-Hammar marsh is necessary to preserve the marsh ecosystem, irrigate lands, and provide domestic necessities in the villages.

The overall project is divided into three main chapters which address the current ecological and hydrological …

3d Printed Pcu/Uhmwpe Polymeric Blends For Artificial Knee Meniscus, Raissa Araujo Borges

Graduate Theses and Dissertations

3D printing was used to fabricate porous artificial knee meniscus material from biocompatible polymeric blends of polycarbonate-urethane (PCU) and ultra-high-molecular-weight polyethylene (UHMWPE) to enable “weep” lubrication that mimics the native meniscus. 3D printed and molded pure PCU, as well as molded PCU and UHMWPE, were used for comparison. Preliminary printing was done to evaluate the impact of process parameters on the results. The samples were subject to a variety of rotational oscillating friction and wear tests under simulated body fluid and loading conditions to replicate the natural motion of the knee. Results show that 3D printed PCU samples yielded a …

Seeing Prehistory Through New Lenses: Using Geophysical And Statistical Analysis To Identify Fresh Perspectives Of A 15th Century Mandan Occupation, Amber Marie Mitchum

Graduate Theses and Dissertations

Great Plains prehistoric research has evolved over the course of a century, with many sites like Huff Village (32MO11) in North Dakota recently coming back to the forefront of discussion through new technological applications. Through a majority of its studies and excavations, Huff Village appeared to endure as the final stage in the Middle Missouri tradition. Long thought to reflect only systematically placed long-rectangular structure types of its Middle Missouri predecessors, recent magnetic gradiometry and topographic mapping data revealed circular structure types that deviated from long-held traditions, highlighting new associations with Coalescent groups. A compact system for food capacity was …

A Molecular Diagnostic Survey Of Pathogens And Parasites Of Honey Bees, Apis Mellifera L., From Arkansas And Oklahoma, Dylan Cleary

Graduate Theses and Dissertations

The health and viability of colonies of the honey bee, Apis mellifera, in the United States have fluctuated dramatically over the past decade. This poses a substantial threat to agricultural production in this country. Currently, no single factor has been identified for this decline. Rather, it has been suggested that the interaction between multiple biotic and abiotic stressors may be responsible. Among these factors are pesticides, habitat loss, climate and weather, parasites and pathogens, and colony management techniques. For this reason, it is important to examine the prevalence of honey bee parasite and pathogen infection at the state level in …

Effect Of Endophyte-Infected Tall Fescue Toxins On Growth Performance And The Microbial Community In The Rumen And Feces In Pregnant Ewes, Saleh Alrashedi

Graduate Theses and Dissertations

Fifty pregnant Katahdin ewes grazed pastures with high (HE) and moderate (MI) levels of Neotyphodium coenophialum-infected tall fescue between February 1 and May 24 to determine the impacts of tall fescue toxins on body weight (BW), body condition scores, FAMACHA scores, fecal egg counts (FEC), and serum Cu, Zn, prolactin, and non-esterified fatty acids (NEFA). Within those 50 ewes, 15 were selected randomly for fecal and rumen sampling to assess the impacts of HE and MI on the microbiome community. Total bacterial DNA was extracted from rumen and fecal samples, and alpha and beta diversities were used to relate microbiome …

In The Field The Women Saved The Crop: The Women’S Land Army Of World War Ii, Denna M. Clymer

Graduate Theses and Dissertations

The Women’s Land Army brought together rural and urban sectors of the United States in a climate of national and regional crisis. By the time the country was cast into war, the agricultural sector was already caught in a downward economic spiral that drove away laborers. With demand falling, and farms propped up only by experiments in subsidy and parity, when military and industrial jobs emerged in urban areas, farm laborers became scarce. At the same time the war created jobs for men outside of the agricultural sector, farm prices recovered and demand soared, forcing farmers to look to women …

Habitat Ecology, Trophic Interactions, And Distribution Of Endangered Himalayan Musk Deer In The Nepal Himalaya, Kapil Kishor Khadka

Graduate Theses and Dissertations

This dissertation seeks to explore and assess the habitat selection, trophic interactions and distribution of Himalayan musk deer. Chapter one deals with seasonal diet analysis of musk deer along with the overlap in consumption with livestock during summer. Microhistological technique was employed to assess dietary consumption. Results showed that Abies spectabilis, Pinus wallichiana, and Berberis species constituted the major portion of musk deer’s diet. Dietary breadth measured by the Shannon index was found higher in winter compared to summer. Although musk deer and livestock shared a considerable number of plant species in their diets, the consumption however was significantly different …

A Study Of The Prevalence Of Gastrointestinal Nematodes In Goats Obtained From Northwest Arkansas, Christine Rose Weingartz

Graduate Theses and Dissertations

Parasitic helminths have always been an issue in small ruminant production; pathogens that pose great negative impact on goat health and productivity. Insufficient work has been done to document the prevalence of parasitic helminths in the United States, especially in the south and southeast, where the largest goat populations are found.

The aim of this study was to survey the prevalence of infections by gastrointestinal nematodes in goats in Northwestern Arkansas. Gastrointestinal tracts were examined from 41 goats of various locations around Northwest Arkansas. Worm species were identified and population burdens were determined. Coprology was correlated with the actual worm …

Agronomic Management Practice Effects On Particulate Organic Matter And Infiltration In A Wheat-Soybean, Double-Crop System In Eastern Arkansas, Johan Desrochers

Graduate Theses and Dissertations

Improving the understanding of conventional and alternative management practices and their interactions on aggregate-derived particulate organic matter (POM) fractions and soil hydraulic properties, particularly infiltration, is instrumental to soil and groundwater management and long-term sustainability in the Lower Mississippi River Delta (LMRD) region of eastern Arkansas. The objective of this long-term wheat (Triticum aestivum L.)-soybean (Glycine max [L.] Merr.), double-crop (WSDC) field study in a silt-loam soil (Glossaquic Fraglossudalf) in the LMRD region of eastern Arkansas was to evaluate the effects of conventional and alternative management practices, including wheat-residue level, residue burning, tillage and irrigation, on i) POM fractions and …

Identifying Genetic Factors Influencing Sperm Mobility Phenotype In Chicken Using Genome Wide Association Studies, Primordial Germ Cell Transplantation, And Rnaseq., Sohita Ojha

Graduate Theses and Dissertations

Sperm mobility is a major determinant of male fertility in chicken. In spite of low heritability of reproductive traits, sperm mobility has high heritability index which suggests presence of quantitative trait loci (QTLs) governing the trait. Our research focused on three objectives: i) to identify the QTLs affecting low mobility phenotype in chicken, ii) to understand the impact of Sertoli-cells and germ cells interactions in influencing the mobility phenotype and iii) to identify the genes and gene networks differentially expressed in male and female PGCs. To detect the QTLs, genome wide association studies (GWAS) was conducted which revealed the presence …

Determination Of The Effects Of Different Maillard Reaction Products On The Taxonomic Composition Of The Gut Microbiota, Nesreen Hamdan Aljahdali

Graduate Theses and Dissertations

The Maillard Reaction (MR) is a non-enzymatic chemical reaction which results in linkage between the amino group of amino acids and the carbonyl group of reduced sugars. This reaction generates Maillard reaction products (MRPs) which are not present naturally in foods, and are responsible for a range of colors, odors, flavors, and other sensory properties. Conflicting reports of MRPs impacts on human health are probably due to the fact that bioconversion of these digestible molecules by the gut microbiota has been marginally taken into account. This study aimed to determine the effects of different MRPs on rodent’s gut microbiota through16S …

Cellular Mechanisms Of Ionoregulation In The Gill Of Japanese Medaka And Rainbow Trout, Rebecca Jo Bollinger

Graduate Theses and Dissertations

Euryhaline fishes are capable of adapting to a wide range of salinities such as freshwater, brackish water or seawater. Through the combined effort of the gill, kidney and intestine, they are able to osmoregulate to maintain a constant internal hydromineral balance. As the gill is in direct contact with the external environment, it is continuously working to maintain ion and acid/base balance, gas exchange and eliminate nitrogenous waste. Fish in freshwater are subjected to osmotic water gain and diffusional ion loss across the gill and experience the opposite in seawater. Therefore, the gill exhibits extreme plasticity when experiencing a change …

Piglet Gut Microbiota Responses To Exposure To Outdoor Simulated Environment And Formula Feeding, Nguyen Vo

Graduate Theses and Dissertations

Several lines of evidence suggest that early-life gut microbiota composition is a crucial determinant of the susceptibility to diseases later in life. Understanding the evolution of early-life gut microbiota and critical factors that can modify this microbial community will espouse the prevention or reversion of health risk originating from dysbiosis of the gut microbiota in the early stage. In this research, we hypothesized that alterations in the environment (simulation of rural conditions by soil exposure) and feeding mode (breastmilk versus formula milk) will have significant impacts on the establishment of the gut microbiota in early life. At first, in literature …

Time Series Forecast Analysis In Wholesale Broiler Markets, Christopher R. Sims

Graduate Theses and Dissertations

In 2016 the chicken industry provided nearly 1.2 million jobs, 68 billion dollars in wages, 313 billion dollars in economic activity and 24 billion dollars in government revenue (John Dunham & Associates, Inc., 2016). Broiler production has changed dramatically from the early 90’s to the turn of the 21st century. Technological advancements, continuous improvements, production efficiencies and industry changes have made the industry the global market it is today. The poultry industry is an extremely volatile market with prices constantly fluctuating in response to input price volatility and demand and supply changes. These changes are often driven by world economic …

Bacterial And Archaeal Nitrifier Communities After Seven Years Surface Ground Cover And Nutrient Management In An Orchard Soil, Mashael Albalawi

Graduate Theses and Dissertations

Nitrification is oxidation of ammonia to nitrite and subsequently to nitrate. The rate limiting step of nitrification, ammonia oxidation to nitrite, was thought for many years to be carried out primarily by ammonia oxidizing bacteria (AOB). However, using molecular techniques and investigating the amoA gene, ammonia-oxidizing archaea (AOA) were discovered. Understanding how long-term application of surface ground covers and organic fertilizers to perennial systems affect microbial communities is critical for sustainable soil management. An organically managed experimental apple orchard soil received seven years (2006 – 2013) of annual, surface applications of poultry litter or commercial fertilizer compared to no fertilizer …

Our Land Is Not Just Soil: Knowing, Feeling, And Doing Environmental Activism In The Arkansas Ozarks, Ramey Arlen Moore

Graduate Theses and Dissertations

The Ozarks is a holey place, an ancient plateau formed from ancient rocks and the sediment of millions of years of living things. The Ozarks is also, from another perspective a place made from a mesh of overlapping lines, lines of migration, lines of living things, lines of water movement over and through the land. This dissertation engages with the practice of conservation and environmentalism as it is performed and lived by Ozarkers and Arkansawyers, natives and transplants. Based on more than a year of ethnographic fieldwork conducted with the Buffalo River Watershed Alliance, Save the Ozarks, Arkansas Master Naturalists, …

Animal Welfare Frames: How Social Media Messages Bridge The Gap Between The Protein Industry And Consumers, Olivia Norton

Graduate Theses and Dissertations

The two articles in this thesis used content analysis to analyze and compare animal welfare related website and Twitter content of the top five animal protein producing companies in the United States. In the first article, the animal welfare website content of Cargill, Tyson Foods Inc., Smithfield, JBS® and Sysco were analyzed for persuasive frames, common topics, and key terminology to describe their corporate positions on animal welfare. Sysco’s main page devoted to animal welfare dominated the word count with 1,045 words, while JBS®’s main animal welfare page used only 265 words to communicate the company’s views. The most commonly …

Modelling The Impact Of National Development Strategies For The East African Rice Sector, Florence Muthee

Graduate Theses and Dissertations

The 2008 food crisis prompted many food importing nations to reconsider the need to be self-sufficient especially in their staple food needs. This awakening led to the launch of the Coalition for Africa Rice Development (CARD) initiative with a goal to double rice production in Africa. Under the CARD umbrella member countries drafted individual National Rice Development Strategies (NRDS). This study is a quantitative assessment of four East African countries’ NRDS: Kenya, Rwanda, Tanzania and Uganda within dynamic global rice economy models. The NRDS targets and strategies are not realistic and included under estimation of rice consumption for Kenya, an …

Effects Of Pre-Chiller Temperature On The Microbial Ecology Of Whole Bird Carcass Rinses, Rachael Elizabeth Blevins

Graduate Theses and Dissertations

Upon entering a poultry processing facility, birds are already contaminated with a variety of microorganisms. It is the responsibility of the processor to reduce these numbers to deliver a wholesome product to customers. This is not an easy task as there are ample opportunities for further microbial contamination. Some of these opportunities are obvious. For example, any areas where contaminants could be washed off one bird and onto another are always an area for concern, i.e. the scalder or the chiller. There are numerous opportunities for contamination that are not so obvious. These incidents of contamination are not necessarily due …

The Cold War In The Eastern Mediterranean: An Interpretive Global History, James M. Brown

Graduate Theses and Dissertations

This thesis offers the first global history of the Cold War in the eastern Mediterranean. It examines the international linkages that bound Greece, Turkey, and Cyprus with superpowers, non-aligned states, and transnational movements during the second half of the twentieth century, and it considers the effects of such linkages upon the eastern Mediterranean’s domestic arenas. Throughout, it demonstrates that two forces – synthesis of outside influence alongside consolidation of internal identities – dictated the region’s experiences during the Cold War. And though the international environment furnished the conditions within which the region’s societies pursued the project of nation-building, indigenous forces …

Population Dynamics Of Ouachita Dusky Salamanders (Desmognathus Brimleyorum) In A Managed Forest Landscape, Kelly Marie Halloran

Graduate Theses and Dissertations

With anthropogenic alteration of landscapes increasing world-wide, managed forests are increasingly important as providers of ecosystem services including habitat for numerous wildlife species. It is crucial to maintain a balance between timber production and conservation of biodiversity on managed landscapes. Salamander populations can play key roles in the function and diversity of temperate forest ecosystems. Several studies have reported negative effects of forestry on terrestrial plethodontid salamanders, but less research has focused on stream-dwelling species, evaluated mechanisms driving observed shifts in abundance, or described the dynamics of populations residing in managed forests. Using a Before-After-Control-Impact design, we examined the effects …

Experimental Approaches To Understand And Control Salmonella Infection In Poultry, Yichao Yang

Graduate Theses and Dissertations

Salmonella is a major foodborne pathogen around the world and chickens are the major reservoir to transmit Salmonella into the human food chain. For decreasing the infection of Salmonella, we developed six attenuated live vaccines based on Salmonella Enteritidis (SE) and Typhimurium (ST) for testing the cross-serovar and cross-serogroup protection from the challenge of Salmonella Heidelberg and Campylobacter jejuni. One of the constructed vaccine strain showed ability to protect against challenge from Salmonella Heidelberg. Even though some preventive approaches are able to decrease Salmonella colonization in the gastrointestinal tract of chickens or other farm animals, Salmonella transmission mechanisms remain unclear. …