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Identification And Characterization Of Salinity Tolerance Genes By Activation Tagging In Arabidopsis, Jawaher Alkahtani

Graduate Theses and Dissertations

Salinity often affects irrigated areas in arid and semi-arid regions of the world. The existence and accumulation of soluble salts in the soil layers limit the growth of crops essential for our food. Salt stress dramatically affects plant growth, plant development, as well as crop yield. Arabidopsis thaliana is the plant model that provides a comprehensive knowledge of plant development, genetics and physiology, and response to abiotic stresses such as salinity. The redundancy of genes due to duplication, even in the simple model genome of Arabidopsis, limits the value of knockout (KO) mutagenesis to provide complete information on gene function. …

The Effects Of Consuming Eggs On The Physical And Cognitive Development Of Food-Insecure Haitian Children, Monica Elaine Stewart

Graduate Theses and Dissertations

Within Latin America and the Caribbean, severe food insecurity is highest in Haiti. Fifty-five percent of the population lives below the poverty line with approximately 50% of the population undernourished. Given the typical diet in the developing world is primarily plant-based, the two studies presented in this thesis examine how eggs, a locally available animal protein, impact physical growth, cognitive development, and motor skills of food-insecure children from a single orphanage in Leogane, Haiti when added to the diet.

In the first study, growth parameters in children ages 3-8 years old were measured at baseline, six months, and one year. …

Body Composition, Muscular Performance, And Free Testosterone Following 12-Weeks Of Protein Supplementation And Resistance Training In Men Aged 35-55, Matthew Steven Stone

Graduate Theses and Dissertations

PURPOSE: The purpose of this study was to investigate the effects of 12 weeks of protein supplementation and Autoregulatory Progressive Resistance Exercise (APRE) training on measures of body composition, muscular performance, and free testosterone in middle-aged men. METHODS: Untrained males (n = 35; 43.3 ± 6.6 years) participated in this study. Lean mass (LM) and fat mass (FM) were measured via Dual Energy X-ray Absorptiometry (DEXA), while strength was measured utilizing one repetition maximum (1RM), endurance measured using maximum repetitions completed (REPS) at 75% 1RM for the bench and leg press, and free testosterone was measured using changes in serum …

The Energy Yield Of Global Crops 1961-2016, Quinn Montana

Graduate Theses and Dissertations

It is often suggested that world food production must increase by 70%-100% or more by the year 2050 if we are to feed the anticipated world population at that time. To evaluate this claim, global crop production from 1961 to 2016 was inventoried using publicly available data from the United Nations Food and Agriculture Organization (FAO). To determine the adequacy of global crop output for humanity, annual global food crop production data (T y-1) were converted to energy yield in kilojoules (KJ y-1). These data were then compared to the annual metabolic energy requirement of the global human population. The …

Effect Of Morinda Citrifolia (Noni)-Enriched Diet On Hepatic Heat Shock Protein And Lipid Metabolism-Related Genes In Heat Stressed Broiler Chickens, Joshua Flees

Graduate Theses and Dissertations

Heat stress (HS) has been reported to alter fat deposition in broilers, however the underlying molecular mechanisms are not well-defined; therefore, the objectives of the current study were to: (1) determine the effects of acute (2 h) and chronic (3 wk) HS on the expression of key molecular signatures involved in hepatic lipogenic and lipolytic programs; and (2) assess if diet supplementation with dried Noni medicinal plant (0.2% of the diet) modulates these effects. Broilers (n=480 males, 1 d) were randomly assigned to 12 environmental chambers, subjected to two environmental conditions (HS at 35°C vs. thermoneutral condition [TN] at 24°C) …

Effect Of Yeast Supplementation During Various Stages Of Beef Production, Elizabeth Palmer

Graduate Theses and Dissertations

Supplemental dietary yeast products are beneficial during times of stress. Calves experience increased levels of stress during birth, weaning, and the post-weaning receiving period. Therefore, 3 experiments were conducted to determine how yeast supplementation affects growth performance and health during this time. In experiment 1, 2 truckloads of highly stressed calves (n = 175; initial body weight [BW] = 226 ± 24.5 kg) were assigned randomly to 1 of 3 treatments; unsupplemented control, or supplementation with 2 commercial yeast products (Y1 and Y2). Average daily gain (ADG) was not different (P = 0.99) during the 28 d receiving period; nor …

Effect Of Grain Sorghum Polyphenols On Fecal Fermentation, Danielle Marie Ashley

Graduate Theses and Dissertations

Obesity is an increasing epidemic which during 2015-2016 afflicted 39.8% of adults and 18.5% of youth in the United States. Not only can obesity affect quality of life, but it can lead to life-threatening diseases such as type 2 diabetes, heart disease, stroke, and some cancers. Animal and human research have demonstrated a pattern of gut microbiota perturbation in overweight and obesity, characterized by a reduction of beneficial bacterial species and increase in harmful species. Diet has been established as a contributing factor in gut ecology, and foods including fiber, resistant starch, and polyphenols have been found to both enhance …

Effects Of Serving Temperature On Sensory Perception And Acceptance Of Brewed Coffee, Matthew James Chapko

Graduate Theses and Dissertations

Coffee continues to be one of the most widely consumed beverages worldwide. How an individual perceives a cup of coffee is impacted by a plethora of factors including origin, growing climate, roasting level, and consumption habits. This thesis utilized both trained descriptive panelists and untrained consumer panelists to analyze how serving/consumption temperature modulates sensory perception of brewed coffee in regards to appearance, aroma, flavor, taste, and mouthfeel. Three varieties of coffee (Colombia, Ethiopia, and Kenya) were brewed and served to panelists at four temperatures: 70, 55, 40, and 25 °C. In one study (Study 1, Chapter 3), results from descriptive …

A Numerical Investigation Of Bio-Inspired Scaffolds And Surface Textures, Yucong Gu

Graduate Theses and Dissertations

Synthetic scaffolds are widely used as implants to repair bone fracture. Without a proper design, scaffolds could pose significant health risks to the patient and fail to heal the bone properly. A good synthetic scaffold needs to have high porosity and large pore size to allow new bone cells to form on it. However, a scaffold with higher porosity and larger pore size tends to have reduced mechanical strength. Thus, it is important to find a structural design which allows the implant to have a high porosity and large pore size while retaining high strength. In this research, a 3D-printable …

Got Breadfruit? Marshallese Foodways And Culture In Springdale, Arkansas, Diana Kay Chen

Graduate Theses and Dissertations

Understanding human food choices is essential in the examination of cultural knowledge and decision-making among members of any ethnic group. Ethnographic and cognitive anthropology methods, including a novel calculation of cognitive salience, were used in this study to explore the domain of traditional Marshallese foods in Springdale, Arkansas. Springdale is home to the highest population of Marshallese people outside of the Republic of the Marshall Islands (RMI); the population is expected to rise as people continue to migrate from the RMI because of global climate change and other factors such as family ties. Studies of traditional foodways are increasingly crucial …

Sustainable Intensification Of Agriculture: Opportunities And Challenges For Food Security And Agrarian Adaptation To Environmental Change In Bangladesh, Aaron Michael Shew

Graduate Theses and Dissertations

This dissertation investigates three unique aspects of sustainable agricultural intensification (SAI) in the context of Bangladeshi rice production. The first article presents a qualitative analysis of SAI and farmer surveys in the embanked polder region of coastal Bangladesh. The second article investigates the global food security and environmental impacts of already adopted High Yielding Variety (HYV) rice and double-cropped rice systems in Bangladesh using a spatial partial equilibrium trade model and a Life Cycle Assessment (LCA). The final article demonstrates a remote sensing methodology for monitoring dry season rice production at 30 m resolution in Bangladesh using a harmonic time …

Cancer-Induced Muscle Wasting, Jacob Levi Brown

Graduate Theses and Dissertations

Cancer-induced muscle wasting, otherwise known as cancer-cachexia, is a wasting syndrome that occurs in approximately 80% of cancer patients that is the primary cause of death for 22%-30% of cancer cases. Cancer-cachexia may be metabolically induced; therefore, the central hypothesis of this dissertation is mitochondrial degeneration occurs before cancer-cachexia, and increased oxidative stress because of mitochondrial degeneration in muscle may instigate cancer-cachexia. Lewis Lung Carcinoma cells (LLC) or PBS (control) were injected into the hind-flank of C57Bl6/J mice at 8 wks age, and tumor allowed to develop for 1, 2, 3 or 4 wks. Mitochondrial quality, function, ROS emission, protein …

The Effects Of Super-Dosing Phytase On Nursery And Grower Pigs, Joshua Paul Knapp

Graduate Theses and Dissertations

To determine the effects of super-dosing on pigs fed phosphorous and calcium adequate or deficient diets (Experiment 1); the optimum level of corn express phytase (CEP, Experiment 2); and the effects of xylanase/phytase on growth performance (Experiment 3) in pigs fed reduce nutrient diets, weaned pigs were blocked with initial body weight (BW) and allotted to dietary treatments. Treatments were: Positive control (PC), P/Ca adequate diets (NRC 2012); Negative Control (NC), low P (-0.15%) and Ca (-0.12%), +0, 1000, and 4000 FTU/kg of CEP in both PC and NC (Experiment 1); PC, P/Ca adequate diets; NC, decreased P (0.15%) and …

Antiproliferative Activity Of Carotenoids, Phenolic Compounds, And Volatile Terpenoids In Carrots (Daucus Carota L.), Brittany Frederick

Graduate Theses and Dissertations

Epidemiological studies have shown an association between high carrot consumption and low prevalence of cancer. This observation has been thought to be attributed to carrot carotenoids. Despite this, various intervention trials have displayed no changes in incidence or increased incidence of cancer with carotenoid supplementation. It is possible that carrot phenolics are responsible for this association, though this has not been widely accepted. Volatile terpenoids from carrots have not been studied in this regard. Therefore, the primary objective of this study was to compare the antiproliferative effects of carotenoids, phenolics, and volatile terpenoids extracted from carrots on Caco-2 colon cancer …

Non-Target-Site Based Tolerance To Herbicides In Amaranthus Palmeri, Reiofeli Algodon Salas-Perez

Graduate Theses and Dissertations

Palmer amaranth, one of the most aggressive and damaging broadleaf weeds in the USA, has evolved resistance to multiple herbicide modes of action. The overall objective of this research was to elucidate the mechanisms by which Palmer amaranth adapt to herbicide selection stress. This research aimed (1) to evaluate the efficacy of fomesafen, glufosinate, glyphosate and trifloxysulfuron to Amaranthus populations; (2) identify candidate genes for endowing tolerance to glufosinate; (3) investigate the involvement of non-target-site resistance (NTSR) mechanism in an ALS-resistant population; and (4) to examine the molecular basis of resistance to PPO inhibitors in Palmer amaranth populations from Arkansas. …

Evaluation Of Fresh-Market Potential Of Arkansas-Grown Fruit: Blackberries, Peaches, Table Grapes, And Muscadine Grapes, Molly Felts

Graduate Theses and Dissertations

Fresh-market produce is a major component of commercial market sales. However, shelf-life of fresh-market produce is limited, so evaluating postharvest potential (time from harvest to consumption) is critical. Fresh-market fruit can be impacted by many factors that deteriorate the quality of the fruit. Understanding the postharvest physiology of fruit can lead to better handling and storage conditions for extended shelf life and enhanced quality for the consumer. This research project was a collaborative effort within the University of Arkansas System Division of Agriculture between the Food Science and Horticulture Departments to evaluate the fresh-market potential of Arkansas-grown fruit. Physiochemical and …

Examining Food Insecurity Among High School Students: A Risks And Resources Model, Jill Niemeier

Graduate Theses and Dissertations

This study examined the relationships between food insecurity, risks, and resources among adolescents attending a large high school in Northwest Arkansas. In a sample of 1,493 students, in which the majority are Hispanic/Latino and receive free and reduced lunch, food insecurity relationships were first assessed controlling for a number of sociodemographic variables, such as ethnicity, gender, and social class. In addition, a number of risk and resource variables were identified at four ecological levels: individual, family, school/peer, and community. These risks and resources were analyzed using a three-step ordinal regression model in order to examine how sociodemographic controls, risks, and …

The Effect Of Cellular Dehydration On Glucose Regulation In Lean And Obese Females, Chunbo Yang

Graduate Theses and Dissertations

A chronically elevated vasopressin level has been associated with an impaired glucose regulation system in humans. A recent study in patients with diabetes suggested that low water intake is associated with impaired glucose regulation. The aim of this study was to examine the effect of hypertonic saline infusion on glucose regulation in healthy females. Thirty healthy, non-diabetic females performed a 2-h infusion followed by a 4-h oral glucose tolerance test (OGTT). Every subject participated in two trials separated by one month, in a counterbalanced order. Two trials were identical in the procedure, differing in the concentration of saline infusion, with …

Evaluation Of The Effects Of Formaldehyde On Growth Parameters Of Broiler Chicks, Paula Johnson

Graduate Theses and Dissertations

Formaldehyde has been used as a disinfectant in poultry hatching cabinets to aid in controlling key pathogenic organisms, such as Salmonella and Escherichia coli (E.coli). There is some evidence that prolonged exposure of chicks to formaldehyde can reduce tracheal ciliary function and thus reasons to believe that exposure to formaldehyde, in the absence of pathogen challenge, may reduce chick vitality. It has been found that elevated temperatures during incubation may adversely affect body weights of broiler chicks, as well as post-hatch environmental heat stress on performance in poultry. Post-hatch environmental heat stress has been shown to impact performance in poultry. …

Survey Of Hydration Knowledge And Behavior In Youth Mountain Bike Teams, Natasha Brand

Graduate Theses and Dissertations

Many youth sports organizations recognize the importance of educating on hydration practices and awareness, although according to recent research current hydration education is not correlating to effective practices. PURPOSE: The purpose of this study was to assess and describe the hydration knowledge and behavior of student-athletes participating in competitive junior high and high school mountain bike teams, in order to substantiate further research. METHODS: A total of 133 male and female participants, ranging from 11-18 years were surveyed on their hydration knowledge and behavior. All participants were apparently healthy and were active members of a National Interscholastic Cycling Association (NICA) …

The Comparison Of Using The Preferred Or Non-Preferred Wrist When Measuring Physical Activity In College Students, Bryce Daniels

Graduate Theses and Dissertations

Introduction. People who participate in regular physical activity have a decreased risk of chronic diseases and premature death. A dramatic decrease of physical activity occurs from adolescence to young adulthood. With important implications to health, physical activity is an important behavior to measure. However, inconsistencies exist on how to measure physical activity. When using accelerometers, differences between the preferred or non-preferred wrist may result in different estimates of physical activity. Purpose. The purpose of this study was to compare the preferred and non-preferred wrist accelerometry measured physical activity using commonly used research accelerometers during structured daily college activities (Actigraph GT3x-bt …

Disordered Eating Risk And Body Image Dissatisfaction Of Division I Male And Female Cheerleaders, Christopher Blaszka

Graduate Theses and Dissertations

The sport of cheerleading is growing both in the high school and college setting, however there is little research on cheerleaders specifically, both sideline and competitive. It is clear that while this sport does not benefit from being affiliated with the NCAA, the athletes are still at large risk for disordered eating and eating disorders, and are in need of more accurate screening and prevention methods. With the lack of cheerleading studies in general, there is an even larger scarcity of studies that focus on males in cheerleading. The current study aims to fill the gap in the research regarding …

The Vaginal Microbiome Related To Reproductive Traits In Beef Heifers, Maryanna Wells Mcclure

Graduate Theses and Dissertations

The greatest impact on profitability of a commercial beef operation is reproduction. In the human vaginal microbiome, dominance by Lactobacillus is a sign of reproductive health and fitness. In other species (non-human primates and ewes), Lactobacillus is found in low amounts and dominators of these microbial communities are considered to be pathogenic in humans. In beef heifers, little is known about the vaginal and fecal microbiota with respect to their relationship with fertility. To this end, we followed heifers through gestation to examine the dynamics of vaginal and fecal microbial composition throughout pregnancy.

Heifers were exposed to an estrus synchronization …

Combining Translational And Functional Genomic Approaches To Augment Management Strategies Of Plant Parasitic Nematodes, Sandeep Sharma Khatiwada

Graduate Theses and Dissertations

Plant-parasitic nematodes pose a major threat to crop yield worldwide. Discontinued use of harmful chemicals has prompted the search for alternative management strategies that are effective yet environmentally friendly. Harpin proteins, which are derived from bacteria, and nematophagous fungi, natural predators of nematodes, are ideal for biological control of plant-parasitic nematodes. However, research on the efficacy of harpin proteins on nematodes, and biology of nematophagous fungi is minimal. Previously, a taxonomically uncharacterized nematophagous fungus designated ARF18 effectively suppressed nematode populations in soil. The overarching goal of this dissertation is to utilize applied and functional genomic approaches to augment management of …

Phylogeny And Evolutionary Genomics Of Non-Photosynthetic Diatoms, Anastasiia Onyshchenko

Graduate Theses and Dissertations

Diatoms are prolific photosynthesizers responsible for some 20% of global primary production. In real terms, the oxygen in one of every five breaths traces back to photosynthesis by marine diatoms. Among the tens of thousands of diatom species, a small handful of colorless diatom species in the genus Nitzschia have lost photosynthesis altogether and rely exclusively on extracellular organic carbon for growth. I used DNA sequence data to reconstruct the phylogeny of this group, and found that nonphotosynthetic diatoms are monophyletic, indicating that photosynthesis was lost just one time over the course of some 200 million years of diatom evolution. …

Consumers’ Willingness To Pay For Hydroponic Lettuce, Daniel Gilmour

Graduate Theses and Dissertations

With continued advances in hydroponic plant production technology, an increasing number of farms have begun using hydroponic techniques to grow leaf lettuce and other food crops in a controlled environment. Recent controversy about the ongoing inclusion of hydroponics in the USDA organic program has highlighted uncertainty about marketing for hydroponic crops. In November 2017, the National Organic Standards Board voted not to recommend that hydroponic farms be banned from applying for organic certification. Since then, continued controversy has led a group of organic producers to start an additional independent certification program that would exclude hydroponic crops. While hydroponic production may …

A Comparison Of Craniofacial Asymmetry In Gorilla Gorilla Gorilla And Pan Troglodytes Troglodytes, Ashly Noel Romero

Graduate Theses and Dissertations

Fluctuating asymmetry (FA) – random deviations from bilateral symmetry in an organism’s paired features – is a good candidate for investigating developmental stability. This easily accessible measurement can be used to understand the relationship between stress and development across organisms, and growth rate plays a vital role in developmental processes. Few studies have investigated craniofacial FA in non-human primates, and those that have suggest that levels of FA are higher in slower growing species. This study examines craniofacial FA in two primate species (Pan troglodytes troglodytes and Gorilla gorilla gorilla; n=81) to elucidate the effect of growth rate on FA …

An Impact Evaluation Of The Government Grant Programs And Input Efficiency Use In The Production Of Greenhouse Tomatoes And Peppers In Kosovo, Blend Frangu

Graduate Theses and Dissertations

Determinants of greenhouse tomato and pepper production input efficiency affect a farmer’s decision to contribute to the vegetable sector in Kosovo. This research investigates the non-optimal use of inputs in the production of greenhouse tomatoes and peppers. Two studies were conducted to first measure input efficiency use and then to quantify the impact of the Ministry of Agriculture, Forestry and Rural Development (MAFRD) grant programs in the production of both crops. The first study applied data envelopment analysis (DEA), and linear and logistic regression to assess factors that influence efficiency in production. The second study used propensity score matching with …

The Effect Of Napping On Sleep Quality And Quantity In Healthy And Concussed Collegiate Athletes, Katie Stephenson-Brown

Graduate Theses and Dissertations

Clinicians are increasingly prescribing a regulated sleep schedule to athletes post injury; however, baseline sleep habits of collegiate athletes are unknown. Moreover, the connection between napping and sleep quality and quantity has not been studied in collegiate athletes. Therefore, the purpose of this study is to investigate napping behaviors and their effects on sleep quantity and quality in concussed and non-concussed collegiate athletes. In a sample of 233 non-concussed collegiate athletes, 74% (172/233) of participants reported napping. Napping was not significantly associated with sleep quantity (χ 2 (2) = .23, p = .64) or quality (χ 2 (1) = .42, …

Effects Of Hydration And Mineralization On The Mechanical Behavior Of Collagen Fibrils, Marco Fielder

Graduate Theses and Dissertations

Bone is a composite biomaterial with a structural load-bearing function. Understanding the biomechanics of bone is important for characterizing factors such as age, trauma, or disease, and in the development of scaffolds for tissue engineering and bioinspired materials. At the nanoscale, bone is primarily composed of collagen protein, apatite crystals, and water. Though several studies have characterized nanoscale bone mechanics as the mineral content changes, the effect of water, mineral, and carbon nanotube (CNT) content and distribution in fibril gap and overlap regions is unexplored. This study used molecular dynamics to investigate the change in collagen fibril deformation mechanisms as …