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The Effect Of Foreign Direct Investment On Food Security: A Case Study From Rural Mozambique, Kali Fleming May 2019

The Effect Of Foreign Direct Investment On Food Security: A Case Study From Rural Mozambique, Kali Fleming

Agricultural Economics and Agribusiness Undergraduate Honors Theses

Poverty and food insecurity in the sub-Saharan African region have been exacerbated by the worst drought in 23 years, which impacted 25 countries in Southern and Eastern Africa from 2015-2016. In Mozambique alone it was estimated that the 2015-2016 drought resulted in over 1.5 million people becoming food insecure (FAO, 2016). To mitigate the increasing problem of household food insecurity in sub-Saharan Africa, the World Food Program recommends job creation to target the most vulnerable populations. Job creation is often the result of Foreign Direct Investment (FDI). However, critics of FDI often cite concerns of human rights abuses, inadequate working …


Light And Shadow Lab: Interest, Experimentation, Collaboration, & Wonder, Mollie Peoples May 2019

Light And Shadow Lab: Interest, Experimentation, Collaboration, & Wonder, Mollie Peoples

General Human Environmental Sciences Undergraduate Honors Theses

Abstract

This creative project focuses on the experimentation and exploration of light and shadows with the children at the Jean Tyson Child Development Study Center (JTCDSC). The creation, development, and implementation of the light studio was influenced by many approaches and concepts that surround early childhood development. It incorporated inspiration from my travels to Italy, where I studied the Reggio Emilia approach in context. In Reggio Emilia, I had the opportunity to visit the Loris Malaguzzi International Centre, local schools that implement distinct child guidance approaches, and The Creative Recycling Centre Remida. The light studio at the JTCDSC incorporates both …


Observations And Applications Of Husbandry Methodologies On A Backyard Poultry Farm In Dangriga, Belize, Bailey Carpenter May 2019

Observations And Applications Of Husbandry Methodologies On A Backyard Poultry Farm In Dangriga, Belize, Bailey Carpenter

Animal Science Undergraduate Honors Theses

This study explores the husbandry methodologies on a backyard poultry farm in Dangriga, Belize, with the purpose of producing a set of guidelines for backyard poultry growers that have limited resources in similar regions. The majority of data collection occurred through survey questions approved by the IRB, necropsies approved by IACUC, and general observations. There has been a steady increase in poultry production in developing regions due to its positive effects on income and relative nutrition. However, due to a lack of accessible communication and education regarding effective and safe poultry production, these operators typically see poor productivity and/or profitability …


Mining For Biological Control Agents Against B. Glumae, The Causal Agent Of Bacterial Panicle Blight Of Rice., Katherine Anne Wilkinson May 2019

Mining For Biological Control Agents Against B. Glumae, The Causal Agent Of Bacterial Panicle Blight Of Rice., Katherine Anne Wilkinson

Graduate Theses and Dissertations

Burkholderia glumae is the causal agent of the emerging disease, Bacterial Panicle Blight of rice, a serious disease that can significantly decrease yield and poses a threat to rice production worldwide. This thesis is concerned with searching for a biological control agent to control this disease. Plant associated microbes are a good source of beneficial bacteria which can be exploited for use as a biological control agent. It is possible that the microbiomes of cultivars which are known to be more resistant to plant pathogens may contain more microbes which inhibit those pathogens and therefore could be used as biological …


Give Up The Ghost, Hannah T. Mcbroom May 2019

Give Up The Ghost, Hannah T. Mcbroom

Graduate Theses and Dissertations

Give Up the Ghost is a series of six paintings created in Fall 2018 and Spring 2019. The paintings are an introspective examination of transgender subjectivity in visual narrative.

In this paper, I separate the personal and research through first and third person, similarly to how I separate imagery and mark making in my paintings. The paper is broken up into a description of the project, the history and theory which informs the work, and why painting is used to describe bodies and spaces.

Give Up the Ghost refers to giving up social expectations as determined by gender. The paintings …


The Impact Of Fall Armyworm, Spodoptera Frugiperda (J.E. Smith), Feeding And Mechanical Defoliation On Growth And Yield Of Rice, Oryza Sativa (L.), Layton Denman Mccullars May 2019

The Impact Of Fall Armyworm, Spodoptera Frugiperda (J.E. Smith), Feeding And Mechanical Defoliation On Growth And Yield Of Rice, Oryza Sativa (L.), Layton Denman Mccullars

Graduate Theses and Dissertations

The fall armyworm, Spodoptera frugiperda (J.E. Smith), (FAW) is a serious pests of many crops, and can be observed feeding throughout the entire growing season on rice, Oryza sativa, (L.). A new defoliation based threshold would help rice growers and consultants make more economically sound decisions for FAW. Work from this thesis focuses on determining the amount of damage caused by FAW feeding at different growth stages and effective insecticide seed treatments for controlling this pest.

Field plots were mechanically defoliated to determine grain yield loss across multiple growth stages and defoliation percentages. Results indicated that defoliation in late vegetative …


The Potential Acidification Of The Mulberry River, Arkansas, Jason Richard Burgess-Conforti May 2019

The Potential Acidification Of The Mulberry River, Arkansas, Jason Richard Burgess-Conforti

Graduate Theses and Dissertations

The Mulberry River is a 110 km long tributary of the Arkansas River in northwest Arkansas and has been designated as a National Wild and Scenic River since 1992. In 2008, the Mulberry River was added to the 303(d) list of impaired water bodies due to the low pH of a 14.6 km segment of the river which has since increased to 68.7 km. To date, there has been little research performed on the Mulberry River and long-term routinely sampled water quality data is unavailable. The objectives of this dissertation were 1) to evaluate changes in water quality of the …


Predicting The Mechanical Properties Of Nanocomposites Reinforced With 1-D, 2-D And 3-D Nanomaterials, Scott Edward Muller May 2019

Predicting The Mechanical Properties Of Nanocomposites Reinforced With 1-D, 2-D And 3-D Nanomaterials, Scott Edward Muller

Graduate Theses and Dissertations

Materials with features at the nanoscale can provide unique mechanical properties and increased functionality when included as part of a nanocomposite. This dissertation utilizes computational methods at multiple scales, including molecular dynamics (MD) and density functional theory (DFT), and the coupled atomistic and discrete dislocation multiscale method (CADD), to predict the mechanical properties of nanocomposites possessing nanomaterials that are either 1-D (carbyne chains), 2-D (graphene sheets), or 3-D (Al/amorphous-Si core-shell nanorod).

The MD method is used to model Ni-graphene nanocomposites. The strength of a Ni-graphene nanocomposite is found to improve by increasing the gap between the graphene sheet and a …


The Role Of Inter-Particle Behavior In Iron Oxide Nanoparticle Induction Heating, Hayden Seth Carlton May 2019

The Role Of Inter-Particle Behavior In Iron Oxide Nanoparticle Induction Heating, Hayden Seth Carlton

Graduate Theses and Dissertations

Due to their multi-functional nature, iron oxide nanoparticles present themselves in a myriad of scientific disciplines, but perhaps the most interesting property of these nanomaterials can be seen in their immense thermal response under the influence of alternating magnetic fields. Currently popularized as an alternative cancer treatment through localized hyperthermia, iron oxide nanoparticle induction heating presents an interesting physical phenomenon that distinguishes itself from macroscopic induction heating. Understanding how a single spherical particle behaves is relatively simple and remains well documented; however, magnetic interactions of a single particle often extend over many length scales, affecting numerous neighboring particles in the …


Investigating The Connection Between Light, A Circadian Clock, And Pathogenesis In Cercospora Zeae-Maydis, John Byron Ridenour May 2019

Investigating The Connection Between Light, A Circadian Clock, And Pathogenesis In Cercospora Zeae-Maydis, John Byron Ridenour

Graduate Theses and Dissertations

Gray leaf spot is a globally important foliar disease of maize caused by the fungus Cercospora zeae-maydis. In C. zeae-maydis, light is a critical environmental signal linked to pathogenesis and secondary metabolism. However, the mechanisms by which the fungus senses and responds to light are not fully understood. Thus, the overarching goal of this project was to unravel the connection between light and pathogenesis in C. zeae-maydis. The conserved fungal protein White Collar-1 (WC-1), designated Crp1 in C. zeae-maydis, senses light and initiates physiological responses. In fungi, WC-1 functions in the White Collar Complex via interaction with White Collar-2 (WC-2). …


Role Of Angiotensin I And Ii On The Tissue Mechanics Of The Aortic Heart Valve Via Receptor Binding And Converting Enzymes, Josh Fahy May 2019

Role Of Angiotensin I And Ii On The Tissue Mechanics Of The Aortic Heart Valve Via Receptor Binding And Converting Enzymes, Josh Fahy

Biomedical Engineering Undergraduate Honors Theses

The renin-angiotensin system (RAS) plays a crucial role in the regulation of renal, cardiac, and vascular physiology. This system regulates in vivo blood pressure and fluid balance. As renal blood flow decreases, the kidneys convert prorenin into renin and secrete it into the circulatory system. Renin then converts angiotensinogen into angiotensin I (ang-I). The ang-I is then converted into angiotensin II (ang-II) by the angiotensin-converting enzyme (ACE). Ang-II, a vasoconstrictor, increases blood pressure by causing the blood vessels to narrow. Recent evidence suggests that RAS may be involved in the progression of valve disease, most notably, aortic stenosis.

The first …


Investigation Of Acute Radiation-Induced Changes In Oxygenation In A Murine Breast Tumor Model, Alaa Abdelgawad May 2019

Investigation Of Acute Radiation-Induced Changes In Oxygenation In A Murine Breast Tumor Model, Alaa Abdelgawad

Biomedical Engineering Undergraduate Honors Theses

Around 50-60% of all cancer patients undergo radiation therapy. Although some patients show complete response with no recurrence, a significant proportion of the population still develop radiation resistance. It is important to identify tumor resistance at early stages of therapy in order to adjust treatment protocol and avoid extra exposure to radiation. Current methods to assess treatment response are only limited to anatomical measurements of tumor volume after therapy. Novel approaches that shed the light on any functional information during the course of radiotherapy could significantly improve our ability to identify patients who do not respond to radiation therapy. Diffuse …


The Effects Of Pre And Post Exercise Low-Level Laser Therapy On Biochemical Markers Of Skeletal Muscle Fatigue In Equines, Carson Freeman May 2019

The Effects Of Pre And Post Exercise Low-Level Laser Therapy On Biochemical Markers Of Skeletal Muscle Fatigue In Equines, Carson Freeman

Animal Science Undergraduate Honors Theses

Our objective was to determine whether administering low-level laser therapy before or after exercise had the greatest effect on biochemical markers of skeletal muscle fatigue in equines such as cortisol and blood lactate. Twelve quarter horses were divided into three groups: Group A received no laser therapy, Group B received laser therapy before exercise, and Group C received laser therapy after exercise. A Class II ERCHONIA ® PL500 handheld low-level laser was utilized for treatment with a wavelength of 635nm. Exercise was utilized using a horse walker system for 30 minutes five days a week for three weeks. Blood was …


Determining The Prevalence Of Injuries, Musculoskeletal Symptoms, And Stressors In Athletic Training Students, Brett Frazier May 2019

Determining The Prevalence Of Injuries, Musculoskeletal Symptoms, And Stressors In Athletic Training Students, Brett Frazier

Health, Human Performance and Recreation Undergraduate Honors Theses

Athletic training is one of the youngest and most rapidly growing professions in the medical field. One of the most prevalent problems with this young profession is the lack of information in the literature about injury, illness, and symptom reporting throughout the course of their career. The purpose of this study was to determine the self-reported prevalence of clinical-related injury, and musculoskeletal disorders/dysfunctions in current athletic training students. I hypothesized that the low back, neck, hand, and knee would be the most frequently affected body areas. Athletic training students from the University of Arkansas were recruited to take this survey. …


Evaluation Of Drought Tolerance In Arkansas Cowpea Lines At Seedling Stage, Qirui Cui May 2019

Evaluation Of Drought Tolerance In Arkansas Cowpea Lines At Seedling Stage, Qirui Cui

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Cowpea [Vigna unguiculate (L.) Walp.] is not only a healthy, nutritious and versatile leguminous crop, it also has a relatively high adaptation to drought. Researches have shown that cowpea lines have a high tolerance to drought, and many of them can survive over 40 days under very hot and dry conditions. The cowpea (Southern pea) breeding program at the University of Arkansas (UA) has been active for over 50 years and has produced more than 1,000 advanced breeding lines. And the purpose of this study is to evaluate the drought-tolerant ability in Arkansas cowpea lines and use the drought tolerant …


Journal Of Food Law & Policy - Spring 2019, Journal Editors May 2019

Journal Of Food Law & Policy - Spring 2019, Journal Editors

Journal of Food Law & Policy

No abstract provided.


Investigating Virus Clearance Via Ph Inactivation During Biomanufacturing, Wenbo Xu May 2019

Investigating Virus Clearance Via Ph Inactivation During Biomanufacturing, Wenbo Xu

Biomedical Engineering Undergraduate Honors Theses

In the processing of biopharmaceuticals, viral clearance and viral safety are important for the development of monoclonal antibodies. Murine xenotropic leukemia virus (XMuLV) is one of the retroviruses, recommended by Food and Drug Administration (FDA) as a model virus for viral clearance via inactivation from therapeutics derived from Chinese hamster ovary cells (CHO). A robust and effective method was investigated to clear or inactivate endogenous viruses by low pH inactivation. The effects of different conductivity and inactivated time on XMuLV clearance was determined. Acetate buffer was prepared with different conductivity, and 2% XMuLV was spiked into acetate buffer. XMuLV virus …


Effect Of Polymer Composition Of Injectable Hydrogels On Programmable Release Of Methylene Blue, Mary Brandecker May 2019

Effect Of Polymer Composition Of Injectable Hydrogels On Programmable Release Of Methylene Blue, Mary Brandecker

Biomedical Engineering Undergraduate Honors Theses

Temperature sensitive hydrogels have been used as injectable hydrogels because the polymer solutions can be liquid at room temperature and gel at body temperature. Injectable hydrogels have been used in biomedical applications to deliver drugs and other small molecules throughout the body. Methylene Blue was used as the drug in this study for its antioxidant and neuroprotective properties. PluronicⓇ F127 (PF127) is a copolymer consisting of repeating units of polyethylene oxide and polypropylene oxide in the form PEO-PPO-PEO. PF127 in solution is a temperature sensitive hydrogel that transitions to a gel at body temperature at specific polymer compositions. A standard …


Phenotypic Characterization Of Differentiation Of Human Mesenchymal Stem Cells To Smooth Muscle Cells, Jackson Hedrick May 2019

Phenotypic Characterization Of Differentiation Of Human Mesenchymal Stem Cells To Smooth Muscle Cells, Jackson Hedrick

Biomedical Engineering Undergraduate Honors Theses

Abdominal aortic aneurysms (AAAs) are expansions in the aortic wall with an increased tendency to rupture. These expansions are triggered by the breakdown of key aortic extracellular matrix (ECM) proteins—elastin and collagen. The degradation of aortic ECM proteins is the consequence of overexpressed matrix metalloproteases (MMPs)–MMP-2 and MMP-9. Adult vascular smooth muscle cells (SMCs) lack the ability to repair the elastic matrix assembly; thus, it is imperative to find a solution to both restore the imbalance of essential ECM proteins in the aorta and mitigate the effects of MMPs. Previous studies have revealed that bone marrow derived mesenchymal stem cells …


Silver-Based Microbial Check Valve For Spacecraft Potable Water Systems, Jennifer Gaines May 2019

Silver-Based Microbial Check Valve For Spacecraft Potable Water Systems, Jennifer Gaines

Chemical Engineering Undergraduate Honors Theses

As human space exploration increases, the development of a more efficient potable water treatment system suited for spacecraft becomes crucial. This Waste-management Education Research Consortium (WERC) challenge was designed to explore the viability of microbial control through the utilization of silver ions as a biocide for possible integration into the Tranquility Node 3 water purification system aboard the International Space Station (ISS). Current systems using iodine risk causing hyperthyroidism from overexposure; however, silver can be safely ingested without this side effect. After researching silver delivery methods including electrochemical ion production, controlled release, or a combination of the two, our team …


The Effects Of Eicosapentaenoic Acid (Epa) And Docosahexaenoic Acid (Dha) On Brown Adipogenesis In Stem Cell Culture, Darynne Dahlem May 2019

The Effects Of Eicosapentaenoic Acid (Epa) And Docosahexaenoic Acid (Dha) On Brown Adipogenesis In Stem Cell Culture, Darynne Dahlem

Animal Science Undergraduate Honors Theses

Polyunsaturated fatty acids (PUFAs), especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are major maternal dietary supplements due to their positive benefits on neurological tissue growth during the first 12 weeks of gestation. Previous studies show that EPA and DHA inhibit muscle formation but promote adipogenesis. However, no research has addressed the question whether high intake of EPA and DHA affects brown fat development during gestation. The objective of this study was to measure the effect of EPA and DHA supplement on brown adipogenesis and potential pathways related to mitochondrial biosynthesis using fibroblasts as in vitro model. Using Oil-Red-O staining …


Development Of A Ws2 Catalyst For Hydrogen Evolution And Improvement Via Platinum Nanoparticle Decoration, Alexander O'Brien May 2019

Development Of A Ws2 Catalyst For Hydrogen Evolution And Improvement Via Platinum Nanoparticle Decoration, Alexander O'Brien

Chemical Engineering Undergraduate Honors Theses

In response to a growing global need to improve utilization of green energy, the concept of renewable energy storage via electrolytic hydrogen production has gained popularity in recent years. However, the prohibitive expense of the bulk platinum catalysts currently used for the hydrogen evolution reaction prevents such a concept from being widely adoptable. This research focuses on a possible alternative catalyst, nanolayer WS2, which is capable of promoting the hydrogen evolution reaction while maintaining economic viability. Bulk WS2 was prepared in semiconducting, nanolayer form through liquid phase exfoliation. Prepared catalyst inks consisting of this material demonstrated successful …


Silver-Based Microbial Check Valve For Spacecraft Potable Water Systems, Rogelio E. Garcia May 2019

Silver-Based Microbial Check Valve For Spacecraft Potable Water Systems, Rogelio E. Garcia

Chemical Engineering Undergraduate Honors Theses

As human space exploration increases, the development of a more efficient potable water treatment system suited for spacecraft becomes crucial. This Waste-management Education Research Consortium (WERC) challenge was designed to explore the viability of microbial control through the utilization of silver ions as a biocide for possible integration into the Tranquility Node 3 water purification system aboard the International Space Station (ISS). Current systems using iodine risk causing hyperthyroidism from overexposure; however, silver can be safely ingested without this side effect. After researching silver delivery methods including electrochemical ion production, controlled release, or a combination of the two, our team …


Electrophysiological Correlates Of Visual Object Category Formation In A Prototype-Distortion Task, Stephanie Marie Long May 2019

Electrophysiological Correlates Of Visual Object Category Formation In A Prototype-Distortion Task, Stephanie Marie Long

Graduate Theses and Dissertations

In perceptual learning studies, participants engage in extensive training in the discrimination of visual stimuli in order to modulate perceptual performance. Much of the literature in perceptual learning has looked at the induction of the reorganization of low-level representations in V1. However, much remains to be understood about the mechanisms behind how the adult brain (an expert in visual object categorization) extracts high-level visual objects from the environment and categorically represents them in the cortical visual hierarchy. Here, I used event-related potentials (ERPs) to investigate the neural mechanisms involved in object representation formation during a hybrid visual search and prototype …


Volumetric Muscle Loss: The Role Of Physical Activity And Autologous Repair On Force Recovery And Signaling Pathways, Richard Perry May 2019

Volumetric Muscle Loss: The Role Of Physical Activity And Autologous Repair On Force Recovery And Signaling Pathways, Richard Perry

Graduate Theses and Dissertations

Volumetric muscle loss affects both military and civilian persons. The hallmark of this injury is incomplete muscle regeneration, excessive fibrosis, and chronic inflammatory signaling resulting in permanent functional loss. Since permanent functional loss drastically reduces quality of life, many studies have been conducted to improve force recovery. Current scientific literature considers a repair strategy of either devitalized scaffolds infused with growth factors or viable tissue plus activating factors to be the more promising interventions for optimal force recovery. PURPOSE The purpose of this study is to incorporate autologous repair and physical activity and observe the effects of muscle force recovery …


Feedforward And Feedback Signals In The Olfactory System, Srimoy Chakraborty May 2019

Feedforward And Feedback Signals In The Olfactory System, Srimoy Chakraborty

Graduate Theses and Dissertations

The conglomeration of myriad activities in neural systems often results in prominent oscillations. The primary goal of the research presented in this thesis was to study effects of sensory stimulus on the olfactory system of rats, focusing on the olfactory bulb (OB) and the anterior piriform cortex (aPC). Extracellular electrophysiological measurements revealed distinct frequency bands of oscillations in OB and aPC. However, how these oscillatory fluctuations help the animal to process sensory input is not clearly understood. Here we show high frequency oscillations in olfactory bulb carry feedforward signals to anterior piriform cortex whereas feedback from the aPC is predominantly …


Reducing The Risk: Psychological And Technological Approaches For Improving Handwashing Practices In The Foodservice Industry, Jeffrey Allan Clark May 2019

Reducing The Risk: Psychological And Technological Approaches For Improving Handwashing Practices In The Foodservice Industry, Jeffrey Allan Clark

Graduate Theses and Dissertations

As Americans are spending greater portions of their dollar on food consumed outside the home, the foodservice industry plays more of an integral part of daily existence compared to previous generations. Given the numerous annual foodborne illness outbreaks that threaten human lives while undermining confidence in the food supply, food safety is a pertinent issue for industry stakeholders, government regulators, and consumers. Food worker handwashing reduces the risk of foodborne illness transmission, yet compliance with this simple behavior is a complex problem. This dissertation addresses, predominantly, the issue of sub-optimal handwashing practices through applying psychology and technology, including wearable computers …


Phylogenomics And Geometric Morphometrics Define Species Flocks Of Snowtrout (Teleostei: Schizothorax) In The Central Himalayas, Binod Regmi May 2019

Phylogenomics And Geometric Morphometrics Define Species Flocks Of Snowtrout (Teleostei: Schizothorax) In The Central Himalayas, Binod Regmi

Graduate Theses and Dissertations

Schizothorax (Snowtrout) is a genus of medium-sized minnows (Cypriniformes) inhabiting glacier-fed streams, rivers, and lakes in the Himalayas. There are more than 30 species of Schizothorax across the region. The speciation and diversity of the Snowtrout in the vast hinterlands of the Himalayan Region has not been fully explored. Three species in Lake Rara, Western Nepal are considered a species flock, comprising endemic ecotypes that are morphologically differentiated and reproductively isolated.

My dissertation research examined the diversity of Schizothorax in the Central Himalayan region and evolutionary relationships among species distributed in the Tibet, Central and Southeast Asia. Chapter I describes …


Effects Of Genre Tag Complexity On Popular Music Perception And Enjoyment, Lauren Shepherd May 2019

Effects Of Genre Tag Complexity On Popular Music Perception And Enjoyment, Lauren Shepherd

Graduate Theses and Dissertations

The popular online streaming platform Spotify added over 1400 genre tags in the last two years. Despite that numerous artists and composition competitions claim to seek projects that “transcend the traditional notion of genre,” the industry has only added more complex and mystifying genre labels. This dichotomy between artists and industry ignores the effects these labels have on consumers. Do more complex genre tags enhance the listening experience for the average consumer by providing additional information about what they are about to hear? The current research seeks to examine the effects of the granularity of genre tags on popular music …


Powers And Behaviors Of Directed Self-Assembly, Trent Allen Rogers May 2019

Powers And Behaviors Of Directed Self-Assembly, Trent Allen Rogers

Graduate Theses and Dissertations

In nature there are a variety of self-assembling systems occurring at varying scales which give rise to incredibly complex behaviors. Theoretical models of self-assembly allow us to gain insight into the fundamental nature of self-assembly independent of the specific physical implementation. In Winfree's abstract tile assembly model (aTAM), the atomic components are unit square "tiles" which have "glues" on their four sides. Beginning from a seed assembly, these tiles attach one at a time during the assembly process in an asynchronous and nondeterministic manner.

We can gain valuable insights into the nature of self-assembly by comparing different models of self-assembly …