Life Sciences Commons^™

The Virome Of Peony And The Population Structure Of Its Most Prominent Viruses, Cullen Shaffer

Graduate Theses and Dissertations

Peony (Peonia lactiflora, Pall.) is a popular ornamental that has been cultivated for millennia. Due to its popularity, plant material is frequently moved across international borders allowing for the spread of viruses. The virome of several peony plants was investigated and four viruses; namely Amazon lily mild mottle virus (ALiMMV), Cycas necrotic stunt virus (CNSV), Gentian Kobu-sho associated virus (GKaV) and Lychnis mottle virus (LycMoV) were detected for the first time in the Western Hemisphere. Incidence ranged from a few plants for ALiMMV to near universal infection for CNSV. GKaV was found in individuals that were infected with Lemoine’s disease …

Parallel Strategies To Control Bacterial Panicle Blight Of Rice, Laura Ortega

Graduate Theses and Dissertations

Bacterial Panicle Blight (BPB) of rice is a seed-borne disease caused by the bacterium Burkholderia glumae. This disease has affected rice production worldwide and its effects are likely to become more devastating with the continuous increase in global temperatures especially during the growing season. Field data has shown that the disease has been more prevalent in years when the temperatures have been unusually high especially at night possibly due to the bacterial adaptation to grow at temperatures higher than 40oC. With the continuous rise in global temperatures, it is likely that this disease will be more problematic. The bacterium can …

A Snapshot Semester: Students’ Reflections Of Performance And Mental State Throughout A Graduate Course, Bradley D. Borges

Graduate Theses and Dissertations

Graduate students are anecdotally reputed to be among the most stressed groups of young adults. Common sources of stress for graduate students have included coursework, assistantships, finances, career preparation, and family (Wyatt & Oswalt, 2013; Mazzola, Walker, Shockley & Spector, 2011; Oswalt & Riddock, 2007). Guided reflection can be used by educators to assist students in both learning (Boud, Keogh & Walker, 2013; Kolb, 1984) and managing stress (Shoulders, Whitehead, & Morrison, 2018). By understanding how students’ progress through a semester in terms of both their learning and their management of stress, instructors and academic advisors can better anticipate times …

Degree Of Conservation Of Methionines Found To Be Oxidized In The Human Urinary Proteome, Alexis Hall

Graduate Theses and Dissertations

In previous work from this laboratory, methionine containing peptides from the human urinary proteome were examined by mass spectrometry for the degree of methionine oxidation to the sulfoxide form. While this demonstrated that many of the methionines detected were capable of being oxidized, the question of whether these methionines are important in the structure and/or function of the parent proteins came about. In some proteins, methionine oxidation has been linked to conformational changes and alteration of function and thus can serve as a mechanism for reversible regulation of activity. It is hypothesized that methionines which might serve a regulatory purpose …

Anti-Inflammatory Properties Of Blackberry Phenolic And Volatile Compounds, Pauline Morin

Graduate Theses and Dissertations

Berries are known for many health benefits including anti-inflammatory properties that lower risks of chronic diseases. These properties have been linked to high concentrations of phenolic compounds, especially anthocyanins. However, the present study hypothesized that volatiles could contribute to the berries’ bioactive properties. Thus, the objectives of this research are to profile the phenolic and volatile composition of 16 blackberry genotypes harvested at the Fruit Research Center of the University of Arkansas and to evaluate the antiinflammatory capacities of three selected genotypes on inflamed cells. Phenolic and volatile profiles were evaluated using chromatographic techniques. The three genotypes A2528T, A2587T and …

Functional And Physiological Role Of Extra-Hypothalamic Corticotropin Releasing Hormone Neurons In The Nucleus Of The Hippocampal Commissure In Regulation Of Stress Response, Hakeem Kadhim

Graduate Theses and Dissertations

Corticotropin releasing hormone (CRH) neurons located within the paraventricular nucleus (PVN) are known to be involved in regulation of stress responses. Recently, CRH neurons were identified above the PVN within the nucleus of the hippocampal commissure (NHpC) that located in the septum. We hypothesized that CRH neurons in the NHpC play a critical role in the stress response due to their rapid activation and could be a part of the traditional hypothalamo-pituitary-adrenal (HPA) axis. The dissertation addresses the role of 1) CRH expressing neurons in the NHpC compared with those within the PVN utilizing two different stressors, food deprivation (FD) …

Characterization Of Genetic Sources Associated With Restorability And Seed Dimension In Arkansas Restorer Rice Lines, Ozgur Azapoglu

Graduate Theses and Dissertations

Hybrid rice (Oryza sativa L.) breeding offers a significant opportunity to enhance rice production, and the cultivation of a male sterile line is the most important factor in the success of cross-breeding. One of the key elements of hybrid rice production is to develop a restorer line that is assigned as the male parent. The restorer lines provide viable pollen for fertilization of the male sterile plant due to the presence of a restorer gene (Rf) in their genomes. Any superior restorer line applied to hybrid rice production must contain genes/quantitative trait loci (QTL) associated with the desirable agronomic traits …

Application Of X-Ray Imaging And Glass Transition Principles In Understanding Rice Kernel Fissure Formation, Zephania R. Odek

Graduate Theses and Dissertations

Rice kernels with internal fractures of the endosperm, fissures, tend to break during milling, leading to head rice yield (HRY) reductions. Minimizing kernel fissuring is thus an important goal of the rice industry. To minimize fissuring during the drying process, a better understanding of the fissuring process and the kinetics thereof is required. The goal of this research was to use X-ray imaging and glass transition principles to better understand rough rice kernel fissuring. First, because the instance when the fissuring process is initiated and completed during the drying process is not well known, an X-ray imaging setup that allows …

An Impedimetric Aptasensing System For The Rapid Detection Of Salmonella Typhimurium, America Sotero

Graduate Theses and Dissertations

Salmonella Typhimurium is a foodborne pathogen associated with raw and undercooked eggs, poultry, beef, fruits, and vegetables. In the United States, Salmonella is responsible for approximately 1.2 million illnesses, 23,000 hospitalizations, and 450 deaths annually. For many years, conventional detection methods such as culture-dependent and PCR-based methods have been the “golden standards” for the detection of this pathogen due to their high sensitivity and reliability. However, they still have some disadvantages such as long enrichment steps and high costs that need to be overcome. The development of a rapid and reliable method for the detection of S. Typhimurium is needed …

Association Mapping For Soybean (Glycine Max L. Merr.) Protein And Oil Content, Joseph Najjar

Graduate Theses and Dissertations

Soybean [Glycine Max (L.) Merrill] is an important economic crop because of its high content of seed protein and oil. Seed oil and protein content are quantitative inherited traits. The genetics of seed protein and oil levels have been extensively studied, with 367 QTL reported for protein and 475 QTL reported for oil to date. Validation of such QTLs, and identification of easily-automatable molecular markers around these QTL will aid the progression of breeding for such traits. The focus of this research was to discover novel and verify previously reported QTL related to protein and/or oil content via Genome-Wide Association …

Comparison Of A T-Trellis And A Rotating Cross-Arm Trellis For Arkansas Blackberry Production, Erika Henderson

Graduate Theses and Dissertations

As blackberry production in the southeastern United States expands, the need for updated cultural practices, like alternative trellis systems that enhance blackberry fruit yield, fruit quality, and economic viability for fresh-market growers are needed. There are challenges to producing high-quality blackberry fruit with high yields in the Southeast due to intense heat, high rainfall, humidity, and heavy pest pressure. Southeastern growers are interested in the rotating cross-arm (RCA) trellis due to its potential to increase yield and fruit quality, however there is minimal research of its use in blackberry production in the Southeast. In 2019 and 2020, a trial was …

Rice Chilling Aeration: Assessment Of Impacts On Grain Quality, Process Modeling And Validation, Soraya Shafiekhani

Graduate Theses and Dissertations

The goal of this study is to demonstrate the effectiveness of applying chilling temperatures during on-farm, in-bin drying and storage to maintain rice quality. Specific objectives include to demonstrate the effectiveness of chilling aeration to preserve rice quality characteristics, determine the drying kinetics of rice under low temperature environments, and develop models to predict heat and mass transfer in rice kernel during drying at low temperature environment. To date, there is limited research describing storability or drying behavior of rice in chilled environments. However, it is understood that chilling of high-moisture, > 21% wet basis rough rice could reduce the time …

Gene Set Testing By Distance Correlation, Sho-Hsien Su

Graduate Theses and Dissertations

Pathways are the functional building blocks of complex diseases such as cancers. Pathway-level studies may provide insights on some important biological processes. Gene set test is an important tool to study the differential expression of a gene set between two groups, e.g., cancer vs normal. The differential expression of a gene set could be due to the difference in mean, variability, or both. However, most existing gene set tests only target the mean difference but overlook other types of differential expression. In this thesis, we propose to use the recently developed distance correlation for gene set testing. To assess the …

Evaluation Of Selected Bacillus Direct-Fed Microbial Candidates In Reduced Energy Diets On Live Performance, Carcass Characteristics, And Foot Pad Dermatitis, Kyle Teague

Graduate Theses and Dissertations

Bacillus spp. are ubiquitous, Gram-positive, spore forming bacteria that are commonly recovered from the environment and gastrointestinal tract (GIT) of poultry. These spores are capable of withstanding harsh condition such as feed pelletization, which facilitates inclusion in poultry feeds. Once ingested by the bird, spores germinate into metabolically active vegetative cells which can produce extracellular enzymes which can hydrolyze otherwise indigestible components of the feed. Soybean meal (SBM) is the gold standard vegetable protein source for non-ruminant animals worldwide and is included in practically all poultry diets in the United States at levels ranging from 10 to more than 30%. …

Implications Of Lysine Acetylation On The Enzymes Of The Tca Cycle, Sumana Venkat

Graduate Theses and Dissertations

The tricarboxylic acid (TCA) cycle is a central route for the energy production via oxidative phosphorylation and is ubiquitous throughout nature. Apart from playing a major role in energy provision, it is also essential for a wide range of physiological functions in any organism. Although an increasing emphasis is laid on the interlinking role of the cycle, its regulation and control are less very less understood. As the field progresses, the consequences of TCA cycle anomalies are shown to be tied to various cancers and other disorders. The matter becomes more complex when considering the varying functions of the isozymes …

Impacts Of Postharvest Temperature Exposure Profiles On Rice Physicochemical Properties, Seth Graham-Acquaah

Graduate Theses and Dissertations

Heated-air drying followed by tempering (HAT) is effective for increasing rough-rice drying rates without compromising head rice yield (HRY). However, heat exposure could affect rice end-use properties. Hypothesizing that the total amount of heat exposure incurred by rice during heated-air drying determines the trend and magnitude of changes in end-use properties, this dissertation sought to 1) characterize the effects of drying and tempering regimen on changes in end-use properties, 2) derive an index to quantify and compare the amount of heat exposure that rice kernels incur during active drying and, 3) relate values of this index to changes in rice …

Improving Breeding Program Efficiency And Genetic Gain Through The Implementation Of Genomic Selection In Diverse Wheat Germplasm, Dylan Larkin

Graduate Theses and Dissertations

Genomic selection (GS) is an important tool for increasing genetic gain for economically important traits in breeding programs. Genomic selection uses molecular markers across the entire genome in order to predict the performance of breeding lines for a trait of interest prior to phenotyping. A training population (TP) of elite germplasm, representative of the University of Arkansas wheat breeding program, was developed in order to predict important agronomic and Fusarium head blight (FHB) resistance traits within the University of Arkansas wheat breeding program through cross-validation and forward prediction.

A genome-wide association study (GWAS) was performed on the TP to identify …

Conditional Distance Correlation Test For Gene Expression Level, Dna Methylation Level And Copy Number, Shanshan Zhang

Graduate Theses and Dissertations

Over the past years, efforts have been devoted to the genome-wide analysis of genetic and epigenetic profiles to better understand the underlying biological mechanisms of complex diseases such as cancer. It is of great importance to unravel the complex dependence structure between biological factors, and many conditional dependence tests have been developed to meet this need. The traditional partial correlation method can only capture the linear partial correlation, but not the nonlinear correlation. To overcome this limitation, we propose to use the innovative conditional distance correlation (CDC), which measures the conditional dependence between random vectors and detect nonlinear relations. In …

Effects Of Long-Term Variation In Temperature On Reproductive Phenology In A Population Of Eastern Bluebirds (Sialia Sialis), Paul Pleiman

Graduate Theses and Dissertations

This study investigates the relationship between multiple temperature variables, to include annual and pre-lay date temperatures with first-egg and mean first-egg lay dates of the eastern bluebird at the Warner Parks in Nashville, Tennessee, USA. Data is collected by citizen scientists for the Eastern Bluebird Nesting Box Project while visiting artificial nest boxes throughout the park and recording observations made during the breeding season. Temperature data is retrieved from the Northwest Alliance for Computational Science and Engineering’s Parameter-elevation Regressions on Independent Slopes Model (PRISM) Climate Group, based at Oregon State University. The analyses showed no correlation between annual or pre-lay …

Evaluation Of Different Ensiling Methods On Storage And Feeding Value Of The Residual Material From Edamame Soybean Processing, Ellen Herring

Graduate Theses and Dissertations

Use of organic waste material by ruminant animals from food processing operations potentially reduces costs and reduces environmental issues from disposal of these residues. Therefore, 2 experiments were conducted to evaluate the storage and feeding value of residual from edamame soybean processing for ruminant animals. Two types of waste streams, waste during harvest time and waste from processing stored material, were ensiled (on a laboratory scale) using various methods and effects on post-ensiling nutritive value were examined. Material from both waste streams were ensiled either without wilting or after wilting; each moisture level was ensiled with and without an inoculant. …

Biogeography Of The Bovine Respiratory Microbiome And Its Relationship With Bovine Respiratory Disease, Jianmin Chai

Graduate Theses and Dissertations

Bovine respiratory disease (BRD) is the most common and costly disease in the beef cattle industry, leading to high morbidity, mortality and huge economic loss. Despite the recent advances in vaccination and antimicrobial techniques, no significant health-improved outcomes have developed. Due to a deep investigation of the microbiome, respiratory microbiotas are known to have important roles for host health and disease. However, BRD specific pathogens have not yet been identified since they are found in both healthy and diseased animals. A systemic and comprehensive study of the biogeography of the bovine respiratory microbiome and its relationship with BRD is lacking …

The Use Of Inorganic And Organic Acids As Short Duration Antimicrobial Dips On Mitigating Pathogens Present On Commercial Chicken During Peri-Harvest, Dana Kristen Dittoe

Graduate Theses and Dissertations

With poultry being the most consumed meat in the United States, poultry processors must provide consumers with safe, wholesome products. As a consequence, poultry processors are faced with the challenge of reducing the presence of foodborne pathogens such as Salmonella spp. and Campylobacter jejuni among raw poultry products. Though multi-hurdle approaches using antimicrobials are placed throughout processing to reduce these pathogens, Salmonella and C. jejuni still persist among raw poultry. Thus, it was the objective of the current dissertation to investigate various antimicrobials, organic and inorganic acids, as short duration dips and sprays as means to reduce common pathogens (Salmonella, …

The Effect Of Epa And Dha On Skeletal Muscle Physiology And Energy Balance, Saeed Jebor Ghnaimawi

Graduate Theses and Dissertations

Eicosapentaenoic acid (EPA) and Docosahexaenoic acid (DHA) supplementation commonly suggested during pregnancy confers many health benefits on offspring and more recently improves fetal BAT development and induces myoblast trans-differentiation into adiopocytes through activating PPARs expression. Embryonic myoblast is a highly flexible cell showing great capacity to change its phenotype into adipocyte in response to EPA and DHA supplementation in many in vitro models. However, a little is known about the identity of derived adipocytes, whether, they change into brown or white adipocyte, and in vivo evidence is still missing. Given that the myogeneis process is initiated at the mid of …

Molecular Genetic Analysis Of Drought Resistance And Productivity Traits Of Rice Genotypes, Yheni Dwiningsih

Graduate Theses and Dissertations

Rice (Oryza sativa L.) is the staple food for a majority of the world’s population, and uses 30% of the global fresh water during its life cycle. Drought at the reproductive stage is the most important abiotic stress factor limiting grain yield. The United States is the third largest exporter of rice, and Arkansas is the top rice-producing state. The Arkansas rice-growing region in the Lower Mississippi belt is among the 10 areas with the highest risk of water scarcity. Adapted U.S. rice cultivars were screened for drought resistant (DR) traits to find sources for breeding U.S. rice cultivars for …

Examining Pathogenesis And Preventatives In Spontaneous And Staphylococcus-Induced Bacterial Chondronecrosis With Osteomyelitis In Broilers, Nnamdi Simon Ekesi

Graduate Theses and Dissertations

Bacterial chondronecrosis with osteomyelitis is the most important cause of lameness in broilers. This is important to poultry production, as it poses animal welfare issues, and causes a significant loss in revenue. The remediation of this disease requires the study of its etiology with fitting models and evaluating preventatives. The research reported herein covers genomic virulence analysis of BCO isolates, mainly Staphylococcus aureus, and Escherichia coli retrieved from lame birds. We found that S. aureus isolates were closest to chicken strains in Europe but may have been in the Arkansas area for a decade. Phylogenomics suggest our S. aureus is …

The Effects Of Multiple Stressors On Stream Communities: The Convergence Of Drought, Nutrient Pollution, And Invasive Species, Robert Joseph Fournier Iii

Graduate Theses and Dissertations

Freshwater systems experience multi-faceted degradation from a variety of ecological and environmental stressors. Three common stressors in these systems, drought, nutrient pollution, and invasive species, have wide-ranging effects on stream population- community- and ecosystem dynamics. We have a broad understanding of how each of these stressors works to influence stream systems independently. However, we still know relatively little about if, and how, these stressors might interact when they co-occur. Though drought is a natural part of many stream systems, all three of these stressors can be exacerbated or facilitated by anthropogenic actions. Accordingly, as human population and resource use continue …

Dietary Regulation Of Successful Aging, Aubree L. Hawley

Graduate Theses and Dissertations

The current growth of the older population is unprecedented in U.S. history. Chronic disease and functional limitation commonly develop prior to old age, leading to prolonged physical disability and decreased well-being. The development of chronic disease and loss of independence is associated with lean body mass (LBM) loss and fat mass gain beginning in middle age. Therefore, it is important to identify modifiable factors to mitigate deleterious shifts in body composition to promote successful aging (SA). The concept of SA is associated with longevity, the absence of disease and disability, and subjective components of well-being, however, an operational definition has …

The Surveillance Of Gastrointestinal Parasitic Nematodes Of Northwest Arkansas Dairy Cattle Using Traditional And Genetic Parasitological Identification Procedures, Eva M. Wray

Graduate Theses and Dissertations

Traditional and genetic parasitological identification procedures were compared using naturaland artificial nematode parasite infections in Holstein steer calves. The traditional parasitological procedures measured fecal egg counts, coprocultures with subsequent larval collection and adult nematodes collected at necropsy. The genetic identification procedures measured ITS-2 sequences extracted from different stages of nematode development: raw feces, concentrated nematode eggs, third stage larvae and adults. The primary nematodes observed were Cooperia oncophora, Cooperia punctata and Ostertagia ostertagi. The traditional techniques were not significantly different from one another, while the genetic sequencing showed variation amongst the different procedures. The raw feces sequences showed the most …

Investigating The Potential Of Microbial Metabolites And Mtor Signaling On Chicken Necrotic Enteritis, Mohit Bansal

Graduate Theses and Dissertations

Necrotic enteritis (NE), caused by C. perfringens and coccidiosis, is responsible for substantial economic loss annually. In the first chapter, we investigated the effect of secondary bile acid on necrotic enteritis. Day-old broiler chicks were randomly assigned to 5 groups of diets supplemented with 0 (basal diet), 0.8, 1.0, and 1.5 g/kg (on top of basal diet) deoxycholic acid (DCA). The birds were challenged with Eimeria maxima (20,000 oocysts/bird) at d 18 and C. perfringens (109CFU/bird/day) at d 23 and d 24 to induce NE. Birds were sacrificed at d 26, and ileal tissue and digesta samples were collected. DCA …

Effects Of Commercial Feed Additives On Growth Performance And Gut Microbiota Of Nursery Pigs, Xiaoyuan Wei

Graduate Theses and Dissertations

To secure animal welfare and maximum production, feed additives are often added to nursery pig diets to increase nutrition digestibility, enhance intestinal health, and prevent or mitigate disease, with the ultimate goal of improving growth performance. This thesis performed a longitudinal analysis using next-generation sequencing to investigate the dynamic changes of gut microbiota in weaned pigs fed commercial feed additives. Chapter II was used to evaluate the effects of organic acid mixture on growth performance and gut microbiota of weaning pigs. This study demonstrated that the inclusion of 0.035% (SBA0.035) or 0.070% (SBA0.070) sodium butyrate in a diet containing 0.5% …