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Nitrogen And Phosphorus Enrichment Effects On Nutrient Supply In Reservoirs: A Small-Scale Approach, Jessalyn G. Kohn

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Eutrophication is a problem in many lakes, but the reduction of nutrient inputs such as nitrogen (N) and phosphorus (P) to combat eutrophication can lead to an oligotrophic state, which may be unable to support healthy aquatic ecosystems. This study examined how different rates of chemical fertilization with N and P during times of nutrient limitation (mid-summer) could affect particulate N and C concentrations in four lakes in northwest Arkansas. Fertilization experiments were conducted in microcosms during the month of July 2014. Water samples from each lake were collected and divided into six treatments: control, P-only, N:P 10, 20, 40, …

Calcium And Magnesium Absorption And Retention By Growing Goats Offered Diets With Different Calcium Sources., Jennifer Long

Animal Science Undergraduate Honors Theses

Calcium addition is necessary in order to balance the high phosphorus concentrations that are characteristic of high-concentrate ruminant diets. However, calcium sources differ in their bioavailability. Our objective was to determine apparent Ca and Mg absorption and retention in goats offered diets containing different sources of Ca. Spanish-Boer goats (n=18; 19.6 ± 1.88 kg) were stratified by BW and sex and randomized to dietary treatments consisting of Purina Antlermax 16 containing either calcium carbonate (CC), Calmin (CM) or Milk Cal (MC). Goats were adapted to a control, corn-based high-concentrate diet on pasture and then moved to individual 1.0 × 1.5 …

Nutritional Deficiencies During The Harvest Season According To Household Consumption And Level Of Nutritional Knowledge: A Case Study Of Northern Mozambique, Maggie Jo Hansen

Graduate Theses and Dissertations

Mozambique is classified as a low income country, the lowest development classification defined by the World Bank. It is underdeveloped in food security, agricultural production, and nutritional status, and research shows its residents are not foreign to poverty and malnutrition. Low protein, starchy foods (maize, rice, wheat, cassava) comprise the majority of the Mozambican diet; these starchy foods are the most available for consumption. Although availability impacts diet, educational barriers may also threaten the knowledge of nutrition and perceptions of healthy foods. Illiteracy and lack of education are extreme challenges to disseminating nutritional education efforts in the rural Nampula region. …

Assessment Of An Industrial Type Radiant Heating System For Drying Rough Rice, Anne Adhiambo Okeyo

Graduate Theses and Dissertations

Rough rice is normally harvested at moisture contents (MCs) higher than that for safe storage. The objective for this study was to investigate the effectiveness of scaled-up infrared (IR) heating followed by tempering steps to dry freshly-harvested rough rice. An industrial type, pilot scale, IR drying equipment, designed to convey rough rice on a vibrating conveyor belt was used in this study. The heating zone of the equipment had catalytic IR emitters powered by natural gas. Freshly-harvested rough rice of long-grain pureline (cv. Cheniere), long-grain hybrid (cv. 6XP 756) and medium-grain (cv. CL 271) cultivars at initial moisture contents (IMCs) …

Multiphoton Imaging Of Labeled Breast Cancer Cells To Quantify Intra And Extracellular Receptors, Sydney C. Wiggins

Biomedical Engineering Undergraduate Honors Theses

Every year 200,000 women in the United States are diagnosed with breast cancer. Of the cases diagnosed, 10% -15% are classified as triple negative breast cancer (TNBC) due to the absence of estrogen, progesterone, and HER-2/Neu receptors. This breast cancer sub-type is markedly more aggressive and twice as likely to develop in premenopausal women. TNBC is resistant to endocrine therapies and current targeted agents, making clinical need for the development of validated therapeutics for TNBC a pressing matter. To initiate drug development, the internalization of directly immunolabeled epidermal growth factor receptors (EGFR) in SK-BR-3 human breast adenocarcinoma cells was quantitated …

Immunomodulation Of Breast Cancer Cells For Whole Tumor Vaccination, Kristina G. Maxwell

Biomedical Engineering Undergraduate Honors Theses

Hematogenous metastasis causes 90% of breast cancer-related deaths.Current therapies include chemotherapy and irradiation following surgery. These therapies are very harmful to the human body and do not elicit an anti-tumor immune response. To create a novel therapeutic, an autologous vaccine increasing the immunogenicity of non immunogenic breast cancer cell lines has been proposed.

To create this vaccine, 4T1 mouse mammary breast cancer cells have been selected as the desired cell line to treat. They are non immunogenic and highly invasive. In order to increase their immunogenicity, first projected, was the addition of cytokines to 4T1 cells to increase the expression …

Microdialysis Studies Using Porcine Pancreatic Elastase To Guide Mathematical Modeling Of Microdialysis Sampling For In Vivo Measurements., Mason W. Young

Biomedical Engineering Undergraduate Honors Theses

Microdialysis sampling uses a semi-permeable membrane to allow solute collection by diffusion. When used in conjunction with other instruments, analytes in question can be quantified. Matrix Metalloproteinases (MMPs) are enzymes involved in numerous biological processes where they serve the role of degrading extracellular matrix. Microdialysis sampling, in coordination with further analysis methods, can be used in order to measure the activity of these enzymes in a region of the body instantaneously. The intention of this project is to determine ways of measuring in vitro activity of elastase from porcine pancreas using determined activity values and the collection of elastase products. …

Local Delivery Of Ctla-4 Blockade Inhibits Growth Of Pancreatic Tumors, Jack Baltz

Biomedical Engineering Undergraduate Honors Theses

Immune checkpoint blockade has demonstrated great potential in activating antitumor immunity. Ipilimumab is a monoclonal antibody which targets cytotoxic T-lymphocyte antigen-4. CTLA-4 belongs to the CD28 class of receptors and is found on the surface of CD4⁺ and CD8⁺ T cells. CTLA-4 acts to suppress the immune system when bound to CD80 and CD86 receptors on antigen presenting cells. Ipilimumab, or anti-CTLA-4, has shown to be effective in significantly extending the survival of patients with metastatic melanoma. However, systemic delivery of Ipilimumab also induces significant side effects such as: colitis, dermatitis, uveitis, and hypophysitis. In order to minimize …

Intravital Microscopy Of Tumor Oxygenation And Glycolytic Demand, Jesse D. Ivers

Biomedical Engineering Undergraduate Honors Theses

There is growing concern about the over treatment of cancer because treatments are based primarily on tumor anatomy. In this study, we aim to begin the process of addressing that issue by developing an intravital technique for optically analyzing tumor biology. Two traits were identified as having significant importance in the aggression of a tumor, vascular oxygenation (SO2) and glycolytic demand. Dorsal skin flap window chambers were implanted and 4T1 and 67NR cancer cells were injected to provide a tumor model for the development of this intravital quantification technique. This study provides a detailed protocol from instrumentation setup to surgical …

Customization Of Titanate Nanofiber Bioscaffolds, Jared Hopkins

Biomedical Engineering Undergraduate Honors Theses

In the field of orthopedic devices implant loosening is a major issue resulting in the majority of device failures. These failures result in the need for costly secondary procedures. To reduce device loosening an improved method of tissue anchoring is required. A previously studied titanate nanofiber bioscaffold has been shown to be safely implantable and to contribute to the differentiation of mesenchymal stem cells to osteocytes. Through the customization of both physical and chemical characteristics this titanate nanofiber bioscaffold was fabricated as a potential means to enhance tissue anchoring for use with orthopedic devices. This customization was enabled by acoustic …

Effect Of Impact Angle On Astrocyte Gene Expression, Nicholas A. Chavis

Biomedical Engineering Undergraduate Honors Theses

Over one million people each year experience some form of traumatic brain injury. Every individual’s injury is different as impacts can affect different parts of the brain in various ways. This study was conducted to test the impact angles effect on astrocytes by measuring gene expression of TNF- alpha, an inflammation marker, and GFAP, a gene released in response to reactive astrocytes, following impacts from 0, 45, and 90 degrees. Results were recorded from Polymerase Chain Reaction via the delta delta Ct method and compared to the control group for to show under-regulation or up- regulation of the genes of …

Investigating The Mechanical Behaviors Of Organic/Inorganic Composite Bone Scaffolds, Parker Davidson

Biomedical Engineering Undergraduate Honors Theses

The regeneration of bone over a large area cannot occur without a structure for the bone cells to bind and divide. The use of an organic/inorganic composite bone scaffold appears to be a promising alternative to the current clinical standard of bone grafting. Bone grafting is very limited, in that the size and shape of the area are hard to replicate and the use of donor tissue can trigger an immunologic response resulting in rejection of the bone tissue. This study experimented with composite bone scaffolds which can be made to fit the shape of the area in which bone …

Effects Of Arachidin-1 And Arachidin-3 On Human Colon Cancer Cells, Jessica L. Bettis

Biological Sciences Undergraduate Honors Theses

Cancer remains a leading cause of death in the state of Arkansas and across the United States. Recent research found that peanuts consumption has been correlated with a decreased risk of cancer. Although limited research has been conducted, phenolic antioxidant compounds found in peanuts, arachidin-1 and arachidin-3, are correlated to a decrease in human leukemia and lung cancer cell growth. The objective of this study was to evaluate the anti-colon cancer effects of these compounds. Experiments were conducted to examine the effects of purified arachidin-1 and arachidin-3 on Caco-2 cell proliferation. Treatment of cells with arachidin-1 (0, 1, 5, 10µM) …

Validation Of The Use Of Doubly Labeled Water For Measuring Metabolic Rate In Timber Rattlesnakes (Crotalus Horridus), Caitlin Hirsh

Biological Sciences Undergraduate Honors Theses

The doubly labeled water method is an isotopic technique for measuring field metabolic rate and water flux rates of free-living animals. We present a validation of the use doubly labeled water for measuring metabolic rate and water loss in Timber Rattlesnakes (Crotalus horridus). For this study seven animals of varying body size were used with masses ranging from 148 to 650 grams. Prior to dosing, blood samples were taken to establish background isotope levels for each animal. Snakes were injected with water enriched with isotopes of oxygen (18O) and hydrogen (2H, deuterium). The injected isotopes were then allowed to equilibrate …

Response Of Leukocyte Profiles To Corticosterone Manipulation In The Prairie Rattlesnake (Crotalus Viridus), Jill E. Guillette

Biological Sciences Undergraduate Honors Theses

Prior work has shown that when animals are stressed they have altered leukocyte profiles. The use of leukocyte profiles could provide an inexpensive and efficient method for determining stress. Here we present a validation of the use of leukocyte profiles for showing induced stress in Prairie Rattlesnakes (Crotalus viridus). Snakes (N=19) with masses ranging from 682g to 137g were used in a repeated measures design to examine the effect of hormone manipulation on leukocyte profiles. During each trial snakes were dosed with either corticosterone and sesame oil (1.1µg/g) or only sesame oil. Prior to dosing, baseline blood samples …

Proteomic Characterization Of Eggshell Membranes And Their Effect On Poultry Physiology And Immunity, Sarbjeet Kaur Makkar

Graduate Theses and Dissertations

The use of antibiotics in poultry growth and disease control has led to antibiotics resistant problem in human beings, which is a big concern among consumers. With the necessity for judicious use of antibiotics in poultry production, alternative strategies to improve disease resistance in poultry production are necessary. The research is more inclined towards using the natural products available to grow healthier and antibiotic free meat animals. In the context of exploring natural and sustainable resource of alternative to antibiotics, the biochemical milieu of eggshell membranes (ESM) were analyzed by using mass spectrometry techniques including matrix assisted laser desorption ionization …

Oxidative Stress Response In Archaea: Elucidation Of Oxidant Sensing And Tolerance Mechanisms In Methanosarcina Acetivorans, Matthew Edward Jennings

Graduate Theses and Dissertations

Methanogens are archaea possessing a conserved metabolic pathway which produces methane. Many of the enzymes in the methanogenesis pathway are Fe-S proteins, meaning methanogens are sensitive to conditions which disrupt Fe-S clusters. Molecular oxygen is capable of disrupting Fe-S clusters through oxidation of the iron atoms. Furthermore, reduced iron can facilitate the production of reactive oxygen species (ROS), meaning methanogens must possess antioxidant mechanisms. Detection and eradication of ROS is important for all cells, due to the potentially fatal consequences of unchecked oxidation. This dissertation presents two separate projects investigating mechanisms the model methanogen Methanosarcina acetivorans possess for dealing with …

Effects Of Diet-Induced Obesity On Extracellular Matrix Remodeling During Skeletal Muscle Regeneration, Michelle A. Tedrowe

Health, Human Performance and Recreation Undergraduate Honors Theses

Skeletal muscle has the ability to regenerate from damage; however, recent studies have reported a negative effect of obesity on skeletal muscle regenerative capacity. The extracellular matrix (ECM) contributes to skeletal muscle structure acting as a scaffold for skeletal muscle. Additionally, skeletal muscle serves as a reservoir for proteins and growth factors that promote regeneration. Optimal skeletal muscle regeneration includes inflammation, ECM remodeling, and myofiber growth. Disruption to any of these processes can negatively affect skeletal muscle regeneration. PURPOSE: The purpose of this study was to determine how diet-induced obesity (DIO) affects ECM remodeling during skeletal muscle regeneration. METHODS: Fifty-six …

Integrative Taxonomy Of North American Torrent Mites (Parasitengona: Torrenticolidae: Torrenticola), Jon Ray Fisher

Graduate Theses and Dissertations

Mites are notorious for being under-studied and incomplete knowledge of distribution, life-history, and morphology are commonplace. They typically gain attention through the relatively few pest species that plague our crops, pets, or bodies. Despite representing a successful radiation with an estimated 3–5 million species, relatively few mite lineages attract research attention from non-acarologists. However, the largest radiation of all mites—Parasitengona—has potential to bridge the gap between specialists and non-specialists. Parasitengona are the butterflies of the mite world. Obvious are the bright red mites searching for pollen on concrete, or the large, furry velvet mites coming out to mate after spring …

A Molecular Approach To Understanding The Effects Of Original-Xpc On The Modulation Of The Cecal Microbiota And The Survival Of Salmonella In The Poultry Host, Stephanie Roto

Graduate Theses and Dissertations

Salmonella is a foodborne pathogen commonly associated with poultry products; the economic burden to the U.S. is estimated to be approximately $693 million (without factoring in contaminated eggs). Recently, there has been pressure to withdraw sub-therapeutic levels of antibiotics (also known as antibiotic growth promoters; AGP) from poultry due to concern over antibiotic-resistant bacteria spreading to the human population. Therefore, various feed additives have been researched for their ability in providing protection against harmful pathogens and their potential growth promoting effects, both of which were attributes of poultry treated with AGP. This thesis consists of a comprehensive literature review that …

Autophagy Regulation After Diet And Exercise In Non-Alcoholic Fatty Liver Disease, Megan Elizabeth Rosa

Graduate Theses and Dissertations

Along with the rise in obesity, rates of non-alcoholic fatty liver disease (NAFLD) have also increased. NAFLD may begin with fat accumulation in the liver, but can progress to non-alcoholic steatohepatitis (NASH), fibrosis, and eventual cirrhosis. With no pharmacological treatment for NASH, lifestyle interventions appear vital to maintaining liver health. Previous work has shown aberrant mitochondrial content/quality and autophagy in models of NAFLD. Exercise is known to improve mitochondrial health and possibly autophagy, thus autophagy may be a key regulatory factor for treatment of obesity induced-NAFLD. PURPOSE: The purpose of the study was to examine how weight loss from diet …

The Role Of Child Anxiety In Parent Sick Role Reinforcement, Sarah Ann Bilsky

Graduate Theses and Dissertations

A large body of evidence suggests that parents can facilitate offspring anxiety in response to bodily arousal. These learning experiences are referred to as “sick role reinforcement,” and are particularly important during adolescence, given the profound bodily changes (e.g., puberty) that characterize this period. Sick role reinforcement is likely important in the context of panic disorder (PD). Panic theorists suggest that parents may enhance panic vulnerability by increasing the threat value of bodily sensations. Although a sizeable body of work has examined the role of parent behavior in these processes, few have examined offspring factors in this process. Additionally, little …

Growth And Productivity Of Irrigated Rice (Oryza Sativa L.) For A Tropical High Altitude Environment In Rwanda, Elie Rene Gasore

Graduate Theses and Dissertations

Yield components, grain yield, biomass and plant N accumulation, and N fertilizer responses of irrigated rice (Oryza sativa, L.) were evaluated for a tropical inland valley environment in the high altitudes in Rwanda. Effects were measured for nitrogen (N) fertilizer rate (0, 60, 90,120,150,180 kg N ha-1), season, growth stage and cultivar of different subspecies and plant types during 2012 dry season (DS) and 2013 wet season (WS) at Cyili Rice Research Farm (1380 m above sea level). Variations in irradiance (17.2± 0.32 MJ m-2 day-1 in DS and 9.4 ± 0.66 MJ m-2 day-1in WS) were linked to seasonal …

Dandy As Disease: Gender Hygiene And British Nineteenth-Century Literature, Sharon Louise Fox

Graduate Theses and Dissertations

“Dandy as Disease: Gender Hygiene and British Nineteenth-century Literature” explores the link between the nineteenth-century dandy, ideas of hegemonic masculinity, and Walter Besant’s The Revolt of Man, a dystopian text in which women have usurped all traditionally-masculine roles, while men are the caretakers and manual workers. The first chapter deals with the historical role of the dandy in the nineteenth-century and how he might be viewed as the cause of the fall of Britain. The second chapter revolves around Besant’s novel, exploring how men are shown to be at fault for Britain’s fall in the eyes of the rest of …

Emergence Phenology And Nematode Associates Of The Woodwasp, Sirex Nigricornis F. (Hymenoptera: Siricidae), In Arkansas And Mississippi Forests, Jessica Ann Hartshorn

Graduate Theses and Dissertations

Sirex nigricornis F. (Hymenoptera: Siricidae) is a native woodwasp in eastern North America that inhabits dead and dying pine trees during its univoltine development. Sirex noctilio is native to Eurasia and North Africa and was discovered in the northeastern United States in 2004 after a century of accidental introductions across the Southern Hemisphere. Since then, it has spread to seven states and southern Ontario. There is concern about its potential to negatively affect the multi-billion dollar pine timber industry of the southeastern United States. Effective monitoring tools are necessary to track the spread and establishment of S. noctilio. Deladenus siricidicola …

Effect Of Potassium Deficiency On Uptake And Partitioning In The Cotton (Gossypium Hirsutum L.) Plant And Detection By A Crop Reflectance Sensor, Taylor Dayne Coomer

Graduate Theses and Dissertations

For cotton (Gossypium hirsutum L.) to grow and develop normally, plants need to uptake the necessary amount of nutrients and use those nutrients in a beneficial fashion. It is recognized that cotton needs a certain tissue concentration of ions to achieve and maintain growth rates (Siddiqi et al., 1987). One of the most essential and abundant nutrients in cotton is potassium (K), second only by mass to nitrogen (N) (Marschner, 1995; Oosterhuis et al., 2013). Potassium exists in the soil in four separate pools and moves through soil to roots mainly through diffusion (Rengel & Damon, 2008; Samal et al., …

Effects Of Delayed Drying And Storage Conditions On Milling, Color, And Viscosity Properties Of Rice, Kathryn Nicole Haydon

Graduate Theses and Dissertations

Head rice yields (HRYs), kernel discoloration, and functional properties are three hallmarks of rice quality, and can be impacted after harvest by storage conditions. This study evaluated impacts on rice quality due to controlled storage at moisture contents (MCs), temperatures, and storage durations that may be incurred during Mid-South rice farming practices. Three hybrid, long-grain cultivars, harvested in Arkansas in 2014 and 2015, were stored in rough rice form at 4 MCs (12.5%, 16%, 19%, and 21%), and 5 temperatures (10°C, 15°C, 20°C, 27°C, and 40°C), for 16 weeks, with samples taken every 2 weeks. After drying and milling, HRYs, …

Barriers To Relative Caregivers' Participation In The Subsidized Guardianship Program In Arkansas, Amanda Breanne Krotke-Crandall

Graduate Theses and Dissertations

Only 12 children of the 45,000 of children being raised by guardians in Arkansas have become participants in the Arkansas Subsidized Guardianship Program. The program, enacted by the Arkansas Legislature in 2011, could potentially help low-income grandparents meet the financial burdens of raising a child, thus creating another avenue of permanency for children within the Arkansas Department of Family Services (DCFS). This research sought to identify what barriers may exist to dissuade participation in the subsidized guardianship program in Arkansas using the theoretical base of Intersectionality. To answer this question the investigator conducted in person interviews with DCFS administrators, and …

The Influences Of Texture And Mastication Pattern On Flavor Perception Across The Lifespan, Curtis Robert Luckett

Graduate Theses and Dissertations

Texture is an often-overlooked food attribute and is known to influence other food characteristics. More specifically, texture has been repeatedly to influence how we perceive flavor. Several studies have linked this change in flavor perception to the altered mastication patterns that accompany texture changes. This dissertation is composed of four studies that were designed to address how American food consumers view texture and other food attributes as well as characterize how texture and mastication can influence temporal flavor dynamics. The first study was a survey that outlined consumer attitudes towards a variety of different foods. This study solidified that texture …

Design Of A Nutrient Reclamation System For The Cultivation Of Microalgae For Biofuel Production And Other Industrial Applications, Heather Sandefur

Graduate Theses and Dissertations

Microalgal biomass has been identified as a promising feedstock for a number of industrial applications, including the synthesis of new pharmaceutical and biofuel products. However, there are several economic limitations associated with the scale up of existing algal production processes. Critical economic studies of algae-based industrial processes highlight the high cost of supplying essential nutrients to microalgae cultures. With microalgae cells having relatively high nitrogen contents (4 to 8%), the N fertilizer cost in industrial-scale production is significant. In addition, the disposal of the large volumes of cell residuals that are generated during product extraction stages can pose other economic …