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Identification And Development Of The Support Needs In Nematology For Arkansas Cooperative Extension Personnel, Mia Gentry Aug 2014

Identification And Development Of The Support Needs In Nematology For Arkansas Cooperative Extension Personnel, Mia Gentry

Graduate Theses and Dissertations

County extension agents are vital to the land-grant university system and are responsible for transferring current, research-based knowledge from the university to the community. In-service training allows agents the means to maintain a current, sound knowledge base. Needs identified by leading nematologists led the researcher of this study to assess if nematology education was a topic that warranted in-service training development for Arkansas Cooperative Extension Service (CES) agents. The researcher also assessed agents' comfort level with job related technology. Of the respondents, 67% identified general knowledge of plant parasitic nematodes necessary to meet the needs of their clientele. Findings from …


A Mixed Methods Approach Of Communication Campaign Development And Assessment: Identifying The Needs Of An Audience And Determining The Value In Evaluation, Tara Johnson Aug 2014

A Mixed Methods Approach Of Communication Campaign Development And Assessment: Identifying The Needs Of An Audience And Determining The Value In Evaluation, Tara Johnson

Graduate Theses and Dissertations

The two articles presented in this thesis used both quantitative and qualitative research methods to examine two distinct stages of communication campaigns: research and evaluation. In the quantitative study, students (n = 440) at the University of Arkansas were surveyed to determine their perceptions of the Arkansas Water Resources Center (AWRC), water resources, and water issues. A questionnaire was developed from an existing instrument, reviewed by a panel of experts, pilot tested, and revised. The researchers found participants were most aware (M = 3.23, SD = 1.14), concerned (M = 4.07, SD = 0.86), and interested (M = 4.10, SD …


Tempo And Mode Of Domestication During The Neolithic Revolution: Evidence From Dental Mesowear And Microwear Of Sheep, Melissa Zolnierz Aug 2014

Tempo And Mode Of Domestication During The Neolithic Revolution: Evidence From Dental Mesowear And Microwear Of Sheep, Melissa Zolnierz

Graduate Theses and Dissertations

The Neolithic Revolution marked a dramatic change in human subsistence practices. In order to explain this change, we must understand the motive forces behind it. Researchers have proposed many different stimuli, with most theories invoking environmental dynamics, human population density increases beyond environmental carrying capacity, and the natural outgrowth of human and plant/animal interactions. However, unanswered questions remain concerning the mechanics of animal domestication. Traditional studies of changing faunal morphology and skeletal population profiles offer some clues, but such research has had limited success identifying stages intermediate between wild and domesticated forms, which makes it difficult to discern initial attempts …


Impedance Biosensors For The Rapid Detection Of Viral And Bacterial Pathogens Using Avian Influenza Virus Subtypes H5n1 And H7n2 And Escherichia Coli O157:H7 As Model Targets, Jacob David Lum Aug 2014

Impedance Biosensors For The Rapid Detection Of Viral And Bacterial Pathogens Using Avian Influenza Virus Subtypes H5n1 And H7n2 And Escherichia Coli O157:H7 As Model Targets, Jacob David Lum

Graduate Theses and Dissertations

This research investigated impedance biosensors for the rapid detection of viral and bacterial pathogens using avian influenza virus (AIV) subtypes H5N1 and H7N2 and Escherichia coli O157:H7 as the model targets, which were chosen due to their impact on the agricultural and food industries. For the detection of AIV H7N2, a single stranded DNA aptamer was selected using systematic evolution of ligands by exponential enrichment (SELEX). The selected aptamer and a previously selected aptamer against AIV H5N1 were used in a microfluidics chip with an embedded interdigitated array microelectrode to fabricate an impedance biosensor for specific detection of AIV H7N2 …


3-D Morphometric Analysis Of The Primate Elbow Joint, Seth Brockman Boren Aug 2014

3-D Morphometric Analysis Of The Primate Elbow Joint, Seth Brockman Boren

Graduate Theses and Dissertations

Large body size requires limb joints capable of supporting said weight, and a species exhibiting sexual size dimorphism may necessitate joint size differences between the sexes of the species. If habitual behavior differs with body size, one may expect to see significant variation in joint morphology between species and the sexes within species. The following analysis tests two hypotheses: (1) that significant differences in joint size between males and females correlate with the magnitude of sexual dimorphism and (2) that there is significant interspecific variance in joint shape between males and females of the same species. The first hypothesis is …


Construction Of 3d Biomimetic Tissue Niches For Directing Pancreatic Lineage Differentiation Of Human Embryonic Stem Cells, Weiwei Wang Aug 2014

Construction Of 3d Biomimetic Tissue Niches For Directing Pancreatic Lineage Differentiation Of Human Embryonic Stem Cells, Weiwei Wang

Graduate Theses and Dissertations

The potential of human embryonic stem cells (hESCs) to differentiate into insulin producing beta cells offers great hope for cell-based therapy for diabetes treatment. However, in vitro pancreatic differentiation of hESCs remains challenging. In the past decade, most protocols for differentiating pancreatic cells have been focused on the use of signaling molecule cocktails on 2D substrates. Studies on embryonic development biology strongly suggest that extracellular matrix (ECM) plays a critical role on hESCs behavior. In this work, we first established a 3D collagen scaffold culture system for hESCs differentiating into definitive endoderm (DE), which is the first and most important …


How Microlending Affects Innovation And Entrepreneurship: Evidence From Ethiopia, Robert Hirth Aug 2014

How Microlending Affects Innovation And Entrepreneurship: Evidence From Ethiopia, Robert Hirth

Graduate Theses and Dissertations

Advocates of microlending suggest it is a sustainable intervention that reaches the poor directly and offers them the means to invest and improve their incomes (Khavul, 2010; Morduch, 1999; Yunus, 2007); yet, impact studies of these interventions have suggested they often have little or even a detrimental impact on borrowers (Van Rooyen, Stewart & De Wet, 2012). This dissertation examines the efforts to promote entrepreneurship and alleviate poverty in developing countries through microlending. I begin by reviewing the microlending literature, and in particular, impact studies of the effect microlending is having in developing countries. Next, I review theory and empirical …


Overcoming Roadblocks In Introducing Virtual World Technology To High Schools, Casey Dylan Bailey Aug 2014

Overcoming Roadblocks In Introducing Virtual World Technology To High Schools, Casey Dylan Bailey

Graduate Theses and Dissertations

The EAST (Environmental And Spatial Technology) Initiative is a non-profit educational organization that provides students in over two hundred schools in eight states with access to advanced computing technologies for the purpose of enabling students to develop technical skills early and to produce solutions to local community problems. Although many high-end technologies are available through EAST, they are desktop solutions that individual students use and there are none that enable students within a school or between schools to collaborate.

This thesis is a saga that documents the identification and removal of many roadblocks to introducing a 3D multi-user virtual simulation …


Software Porting Of A 3d Reconstruction Algorithm To Razorcam Embedded System On Chip, Kevin Curtis Gunn Aug 2014

Software Porting Of A 3d Reconstruction Algorithm To Razorcam Embedded System On Chip, Kevin Curtis Gunn

Graduate Theses and Dissertations

A method is presented to calculate depth information for a UAV navigation system from Keypoints in two consecutive image frames using a monocular camera sensor as input and the OpenCV library. This method was first implemented in software and run on a general-purpose Intel CPU, then ported to the RazorCam Embedded Smart-Camera System and run on an ARM CPU onboard the Xilinx Zynq-7000. The results of performance and accuracy testing of the software implementation are then shown and analyzed, demonstrating a successful port of the software to the RazorCam embedded system on chip that could potentially be used onboard a …


Essays On Smallholder Farmers In Jamaica: Context-Specific Evidence For Food Security Policymaking, Deborah Evadne Brown Aug 2014

Essays On Smallholder Farmers In Jamaica: Context-Specific Evidence For Food Security Policymaking, Deborah Evadne Brown

Graduate Theses and Dissertations

This dissertation is comprised of three essays that examined the experiences and welfare of traditional food crop farmers in Western Jamaica. It systematically analyses the interplay between smallholder farmers and often overlooked variables in society. The study used qualitative interviewing, field observations and discourse analysis techniques to generate context-specific evidence for food security policymaking.

The first essay examined smallholder farmers' motives for farming. This formed the basis for a farmer typology that provides a portrait of the participants, and was used to inform findings in subsequent essays in this dissertation. The theory of planned behavior provided the conceptual grounding and …


A Novel Cell Based Assay For Mmp Inhibitor Screening, Pantrika Krisanarungson Aug 2014

A Novel Cell Based Assay For Mmp Inhibitor Screening, Pantrika Krisanarungson

Graduate Theses and Dissertations

Up to date, a plethora of protein based materials are used as implants to stimulate tissue regeneration or fillers to alleviate tissue or organ impairment. This includes glottal insufficiency, urinary bladder incontinence and especially in cosmetic industrial to improve facial contour. Once in vivo, protein-based materials are decomposed by cell secreted matrix metalloproteinases (MMP) and lose their volume within months. By introducing MMP inhibitor (MMPI), the extent of material degradation over time may be reduced. In this dissertation, the development of cell-based assay capable of identifying MMPI candidates for protein-based implant lifetime prolongation is described. To visualize the degradation, DQ-gelatin, …


Ethnocultural Differences In Motivations For Sex, Arthur Robert Andrews Iii Aug 2014

Ethnocultural Differences In Motivations For Sex, Arthur Robert Andrews Iii

Graduate Theses and Dissertations

Motivations for sex are numerous and varied (Browning, 2004; Meston & Buss, 2007). Using exploratory factor analytic methods, 21 theoretically distinct motivations have been proposed (Browning, 2004; Meston & Buss, 2007). A comprehensive number of motivations for sex has yet to be examined with confirmatory techniques. Theoretical work related to the treatment of sexual dysfunction has suggested that motivations focused on individual and partner pleasure would positively relate to sexual functioning (e.g., Leiblum & Rosen, 1992). Motivations for sex also appear to vary as a function of ethnocultural factors, as some motivations have only been uncovered utilizing qualitative methods with …


Animal Science E-Newsletter, July 2014, University Of Arkansas, Fayetteville. Department Of Animal Sciences Jul 2014

Animal Science E-Newsletter, July 2014, University Of Arkansas, Fayetteville. Department Of Animal Sciences

Animal Science e-Newsletter

No abstract provided.


Annual Financial Report Supporting Schedules, 2013-2014, University Of Arkansas, Fayetteville Jun 2014

Annual Financial Report Supporting Schedules, 2013-2014, University Of Arkansas, Fayetteville

Annual Financial Report

No abstract provided.


Annual Report, 2013-2014, University Of Arkansas, Fayetteville. Office Of The Vice Provost For Research And Economic Development Jun 2014

Annual Report, 2013-2014, University Of Arkansas, Fayetteville. Office Of The Vice Provost For Research And Economic Development

Research and Innovation Annual Report

No abstract provided.


Animal Science E-Newsletter, June 2014, University Of Arkansas, Fayetteville. Department Of Animal Sciences Jun 2014

Animal Science E-Newsletter, June 2014, University Of Arkansas, Fayetteville. Department Of Animal Sciences

Animal Science e-Newsletter

No abstract provided.


Economic Contribution Of Agriculture And Food To Arkansas' Gross Domestic Product 1997-2011, Jacob Manlove, Leah English, Jennie Popp, Wayne Miller May 2014

Economic Contribution Of Agriculture And Food To Arkansas' Gross Domestic Product 1997-2011, Jacob Manlove, Leah English, Jennie Popp, Wayne Miller

AAES Research Reports and Research Bulletins

Agricultural production, processing, and retail industries are major contributors to the Arkansas economy in terms of GDP. Agriculture contributes to the economy through direct agricultural production, value-added processing, and agricultural retail activities, and it also plays an important role through its interactions with other sectors. The use of non-agricultural goods and services as inputs into the agricultural sector promotes diversified growth in Arkansas’ economy; thus agriculture remains a vital part of Arkansas’ economy. Part 1 of the report compares the relative size of the Agriculture and Food Sector in Arkansas with those of neighboring states, the Southeastern region of the …


The Design And Implementation Of A Lightweight Game Engine For The Iphone Platform, Luke B. Godfrey May 2014

The Design And Implementation Of A Lightweight Game Engine For The Iphone Platform, Luke B. Godfrey

Computer Science and Computer Engineering Undergraduate Honors Theses

In this thesis, the design for a two dimensional game engine for the iPhone using the entity component system (ECS) model is presented as a solution to enable developers to streamline game development. Some background concepts are explained, including the ECS model and a brief overview of part of the iOS SDK used in this project. Related work is explored. An implementation of the design is then described in detail, presented as two parts: a framework and a core set of systems. Finally, the implemented engine is evaluated according to three criteria: ease of use, flexibility, and efficiency. The results …


Palatability Of Teff Grass By Horses, Rachel R. Cummins May 2014

Palatability Of Teff Grass By Horses, Rachel R. Cummins

Animal Science Undergraduate Honors Theses

Most forages commonly used to feed horses have potential detriments including blister beetles or excessive fiber concentrations. Teff grass (T), a warm-season annual forage, has the potential to be a good alternative for horses because of its lack of observed disorders. Our objective was to compare preference by horses for T harvested under different conditions with that of bermudagrass (B) harvested at two maturities. Six different forages were evaluated: T harvested at the late vegetative stage (TLV), at late bloom but that incurred 33 mm of rainfall between mowing and baling (TLBR), with caryopsis visible (TES), or at soft dough …


Biology And Control Of Rice False Smut Caused By Ustilaginoidea Virens (Teleomorph Villosiclava Virens), Andrew Clayton Jecmen May 2014

Biology And Control Of Rice False Smut Caused By Ustilaginoidea Virens (Teleomorph Villosiclava Virens), Andrew Clayton Jecmen

Graduate Theses and Dissertations

Rice false smut (FS), a disease caused by Ustilaginoidea virens (Cke.) Takahashi (1896), was first reported in northeastern Arkansas counties in 1997. The first objective of this research was to establish a collection of U. virens isolates from geographically diverse regions of Arkansas. Three U. virens isolates and chlamydospores from `Templeton' and `Clearfield-151' rice cultivars were used to determine the effects of temperature and pH on mycelial growth and germination. A nested-PCR protocol and histological methods were used to determine if U. virens infects and colonizes rice seedlings and spikelets on panicles. The sensitivity of three U. virens isolates was …


Rapid Condition Assessment Of Bridges By Falling Weight Deflectometer, Jeremy David Rawn May 2014

Rapid Condition Assessment Of Bridges By Falling Weight Deflectometer, Jeremy David Rawn

Graduate Theses and Dissertations

The objective of this thesis is to investigate the feasibility of using a Falling Weight Deflectometer (FWD) as an impact source to rapidly assess the condition of an in service bridge through the evaluation of its modal properties. Tests were conducted on two bridges, a Parker Pony Truss and a modern concrete deck on rolled steel beam bridge. Two full tests were performed on these structures with a hand held impact hammer and a falling weight deflectometer as sources for excitation. The advantage of using a FWD is that many transportation agencies already use these machines for pavement testing and …


Taxonomic And Seasonal Variation Among Extant Hyracoids Based On Dental Microwear Texture Analysis, Ann Marie Walcutt May 2014

Taxonomic And Seasonal Variation Among Extant Hyracoids Based On Dental Microwear Texture Analysis, Ann Marie Walcutt

Graduate Theses and Dissertations

A number of works have been published on habitats and diets of living hyraxes but much remains to be learned about the paleoenvironment contexts of the much larger, more dominant but now extinct forms of the order. Here, I analyze the dental microwear of modern hyraxes to assess dietary and ecological relationships among the four extant species of Procaviidae: Heterohyrax brucei, Procavia capensis, Dendrohyrax arboreus, and Dendrohyrax dorsalis. The purpose of this study was to establish an extant baseline series for the interpretation of microwear texture patterns, and inference of diets, of extinct members of the …


Isoflupredone Acetate As Ancillary Therapy For Bovine Respiratory Disease In High-Risk Stocker Calves, Claire E. Crews May 2014

Isoflupredone Acetate As Ancillary Therapy For Bovine Respiratory Disease In High-Risk Stocker Calves, Claire E. Crews

Animal Science Undergraduate Honors Theses

Bovine respiratory disease (BRD) is the leading cause of illness and death in U.S. feedlot cattle. This study evaluated the use of isoflupredone acetate in the treatment of BRD. Crossbred male beef calves (n = 192; BW = 221 ± 3.9 kg) were acquired in two blocks from regional auction markets and transported to the University of Arkansas Stocker and Receiving Cattle Unit. Calves were observed daily for signs of respiratory illness. Antibiotic treatment was administered if calves displayed signs of respiratory illness and rectal temperature was ≥ 40 °C. Calves (n = 72) requiring antibiotic treatment were assigned randomly …


Journal Of Food Law & Policy - Spring 2014, Journal Editors May 2014

Journal Of Food Law & Policy - Spring 2014, Journal Editors

Journal of Food Law & Policy

No abstract provided.


Alteration Of Host Cell Ubiquitination By The Intracellular Bacterial Pathogen Coxiella Burnetii, Lindsey Elizabeth Pritchett May 2014

Alteration Of Host Cell Ubiquitination By The Intracellular Bacterial Pathogen Coxiella Burnetii, Lindsey Elizabeth Pritchett

Poultry Science Undergraduate Honors Theses

The intracellular bacterial agent of Q fever, Coxiella burnetii, replicates within a phagolysosome-like parasitophorous vacuole (PV) in human macrophages and delivers effector proteins to the host cytosol via a Dot/Icm type IV secretion system (T4SS). T4SS effectors are critical for PV formation and prevention of host cell death that allows sufficient time for bacterial replication. Recruitment of ubiquitin-related components to the C. burnetii PV is also predicted to be involved in PV formation and bacterial replication and is likely controlled by effector proteins. In this study, we assessed the role of the Dot/Icm T4SS in regulating ubiquitination by comparing subcellular …


Optimizing In Vitro Extracellular Matrix Production Using Polymer Scaffolds With Targeted Pore Size, Addison M. Walker May 2014

Optimizing In Vitro Extracellular Matrix Production Using Polymer Scaffolds With Targeted Pore Size, Addison M. Walker

Biomedical Engineering Undergraduate Honors Theses

Extracellular matrix (ECM) has been shown to provide the framework needed for healthy tissue to grow after experiencing an injury. The optimization of growing ECM is a pressing concern in the tissue regeneration field. From prior research, an in vitro approach for harvesting ECM has been created using polyurethane (PU) foams seeded with cells. Our approach aimed at discovering if the pore size of the foams increased the amount of recovered ECM. Scaffolds of targeted pore size were created by separating sugar granules using a sieve, packing the sugar into a cylindrical mold, then pouring PU over the sugar. Three …


How Imbalanced Excitation And Inhibition May Cause Low Entropy Brain Dynamics, Qusay Redwan Alfaori May 2014

How Imbalanced Excitation And Inhibition May Cause Low Entropy Brain Dynamics, Qusay Redwan Alfaori

Biomedical Engineering Undergraduate Honors Theses

To study the effect of the imbalance of excitation and inhibition neurons on brain entropy using a computer model of a brain. The brain model will be composed of a neural network and entropy of the neural network will be measured quantitatively. Entropy in this context quantifies how many different patterns of activated neurons the brain can create. Imbalance between excitation and inhibition neurons causes the brain to malfunction, which can be an underlying cause of autism.


5ht And The 5ht Receptors- Relevance To Cardiac Valve Disease, Christopher Ryan Martindale May 2014

5ht And The 5ht Receptors- Relevance To Cardiac Valve Disease, Christopher Ryan Martindale

Biomedical Engineering Undergraduate Honors Theses

Recent studies have revealed that elevated levels of serotonin or 5HT lead to valve dysfunction. A mouse model was successfully established to investigate the effects on the aortic valve in subjects with elevated 5HT levels along with cardiovascular hypertension. For each two-week trial, eight C57BL/6J mice were divided into the following expermental groups: control, 5HT, angiotensin II, and 5HT+angiotensin II. The drug was delivered to the mice via osmotic pumps (Ang II: 0.4ng/g/min, 5HT:0.0025ng/g/min) or direct injections(Ang II: 0.1 mg, 5HT: 2.12 mg, every other day) and the blood pressure of the mice was continually monitored via the CODA tail …


The Financial Crisis Was Good For Something: Improved Nonprofit Efficiency, Caitlin Paige Britt May 2014

The Financial Crisis Was Good For Something: Improved Nonprofit Efficiency, Caitlin Paige Britt

Finance Undergraduate Honors Theses

This study explores the need for financial performance measures in the nonprofit sector and the impact the 2008-2009 Financial Crisis had upon nonprofits’ efficiency. This analysis tests the hypothesis that the financial crisis actually improved nonprofit efficiency by forcing nonprofits to eliminate unnecessary costs, continue to produce their services, thus improving operational efficiency, despite decreased donor contributions and increased user need. Entries reported on nonprofits’ IRS 990 forms from 2003-2010 determined whether nonprofit efficiency was significantly different after the crisis. The efficiencies used to measure the impact of the Financial Crisis include: Program Expense Efficiency, Administrative Expense Efficiency, Fundraising Expense …


Bermudagrass Growth In Soil Contaminated With Hydraulic Fracturing Drilling Fluid, Douglas Carl Wolf May 2014

Bermudagrass Growth In Soil Contaminated With Hydraulic Fracturing Drilling Fluid, Douglas Carl Wolf

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Hydraulic fracturing is the process of injecting aqueous solutions at high pressure to break apart rock formations and increase the efficiency of natural gas extraction. The solutions are recovered and have been land-applied as one disposal technique. Excessive fluid application can result in increased soil salinity that can inhibit or prevent plant growth. The objective of this greenhouse study was to evaluate the effects of inorganic fertilizer, broiler litter, and Milorganite® and soil depth interval (0-15 cm or 0-30 cm) on the growth of bermudagrass [Cynodon dactylon (L.) Pers] in soil that was collected from a site that had been …