Digital Commons Network^™

Influences Of Contexts On Consumers' Visual Attention Towards Food Images: Eye-Tracking Studies, Baoyue Zhang

Graduate Theses and Dissertations

Food perception is influenced not only by sensory properties of the food itself, but also by individuals- or environment-related contexts. Visual cue appears to be the most dominant factor in modulating food perception. This research aimed to determine whether individuals' visual attention towards food images can vary as a function of contextual variables such as hunger/fullness (Chapter 3), chronic stress (Chapter 4), and culture (Chapter 5). In Chapter 3 and Chapter 4, participants were asked to freely view visual slides, including four different images per slide, shown on the monitor. Using eye-tracking techniques, participants' visual attention towards food images (e.g., …

Integration Of Herbicide Programs With Cultural And Mechanical Practices For Managing Glyphosate-Resistant Palmer Amaranth (Amaranthus Palmeri) In Soybean (Glycine Max), Holden Bell

Graduate Theses and Dissertations

Herbicide-resistant Palmer amaranth is the most troublesome weed in Arkansas row crops, causing producers to rely heavily on multiple mechanisms of action to reduce selection pressure for further evolution of herbicide resistance and to successfully produce a profitable crop. It is critical for the sustainability of weed management not only to adequately control this weed but also to reduce the soil seedbank using both non-chemical and chemical practices. Studies were conducted to determine the effect of soybean row spacing, seeding rate, and herbicide program on Palmer amaranth emergence, survival, and seed production in soybean, the effect of drill-seeded soybean population …

Switchgrass Cultivar, Harvest Frequency, Fertilizer Source, And Irrigation Effects On Near-Surface Soil Properties In West-Central Arkansas, Alayna A. Jacobs

Graduate Theses and Dissertations

Switchgrass (Panicum virgatum L.) has been identified as a model bioenergy feedstock crop and is expected to become an important feedstock for future renewable fuel generation. Agronomic management combinations that maximize monoculture switchgrass yield are generally well understood; however, little is known about corresponding effects of differing switchgrass management combinations on near-surface soil properties. The objective of this research was to determine the residual near-surface soil property effects of three years (2008 to 2011) of consistent management combinations to maximize switchgrass biomass production, including cultivar (‘Alamo’ and ‘Cave-in-Rock’), harvest frequency (1-cut and 2-cut systems per year), fertilizer source (poultry …

Development And Characterization Of An Autologous Whole Cell Breast Cancer Vaccine, Samantha Leigh Kurtz

Graduate Theses and Dissertations

Approximately 40,000 women will die from breast cancer in the United States in 2014. About 90% of these deaths will be due to metastases, rather than the primary tumor and majority of metastases are due to the recurrence and progression of non-metastatic disease. Current adjuvant treatments, such as chemotherapy and radiation, have severe side effects and may result in overtreatment and drug resistance.

Since greater than 90% of patients are diagnosed between stages I-III and have minimal residual disease after treatment, there is an opportunity to treat patients with an autologous breast cancer vaccine. Autologous vaccines under development have a …

Effects Of Water Column P-Availability And Litter Microbial Mediated Processes And Stoichiometry In Aquatic Systems, Ayla Smartt

Graduate Theses and Dissertations

Anthropogenic nutrient enrichment of aquatic ecosystems is prevalent and can have detrimental effects on biological condition. Many of these effects have been attributed directly or indirectly to changes in autotrophic processes. However, in detrital-based streams changes in course detrital stoichiometry and decomposition have been related to changes community structure and production at higher trophic levels highlighting the importance of considering the heterotrophic microbial responses to enrichment. Leaf litter stoichiometry, which is determined in part by the tree species source and the microbial communities that comprise the associated biofilm, is likely related to decomposition rates, but few studies examine these variables …

Applications Of A New Geodata Crawler For Landscape Ecology: From Mapping Natural Stream Hydrology To Monitoring Endangered Beetles, Douglas Ryan Leasure

Graduate Theses and Dissertations

An investigation of endangered American burying beetle (Nicrophorus americanus) ecology led to development of a Geodata Crawler with applications in eco-hydrology. Geodata Crawler includes a national GIS (geospatial information systems) database with layers that quantify climate, land cover, soils, human development, and other attributes of the biosphere. For user-locations in the continental United States, Geodata Crawler can rapidly tabulate site-specific statistics within automatically delineated sample areas: points, site radii, watersheds, and riparian zones, among others. Geodata Crawler supported a multi-scale analysis of N. americanus habitat at a military installation in western Arkansas to produce a Landsat-based monitoring tool. Royle's N-mixture …

Cross-Cultural Comparison In The Emotional Responses Elicited By Wine Odors, Aimee Hasenbeck

Graduate Theses and Dissertations

To remain competitive in the wine market, wine companies must strive for a deeper understanding of the factors that influence consumers at an emotional level in order to sustain consumer satisfaction. Evaluating the wine odor-induced emotional response, in addition to hedonic response and descriptive analysis, may provide valuable information into the perspective of the consumer and potentially insight to repeat purchases. The objectives of this research were to measure the emotional responses elicited by odor attributes in wine samples and determine whether these emotional responses vary as function of cultural and experiential backgrounds, as well as sensory characteristics of wine …

Acanthamoeba Spp. As Reservoirs For Transmission Of Norovirus, Tun-Yun Hsueh

Graduate Theses and Dissertations

Human noroviruses (HuNoV) are the most common cause of foodborne disease outbreaks in the United States and the most common food commodities implicated in HuNoV outbreaks are leafy greens; however, the vehicle of transmission and point of contamination are often unknown. Here, we hypothesize that common free-living amoebae (FLA) ubiquitous in the environment may act as reservoirs of HuNoV and facilitate the transmission of these pathogens to fresh produce. The objective of this research was to first evaluate the interaction/association between HuNoV surrogates and Acanthamoeba by incubating them together and analyzing virus titer associated with amoeba through an 8 day …

A Portable Impedance Biosensing System Based On A Laptop With Labview For Rapid Detection Of Avian Influenza Virus, Yixiang Wang

Graduate Theses and Dissertations

Avian Influenza Virus (AIV) H5N1 is a highly pathogenic virus found not only in birds but also in human. Rapid and sensitive detection method is needed to help prevent the spread of AIV H5N1. In this study, a portable impedance biosensing system based on a laptop with LabVIEW software was developed for detection of AIV H5N1. First, a virtual instrument was programmed with LabVIEW software to form a platform for impedance measurement, data processing and control. The audio card of a laptop was used as a function generator while a data acquisition card was used with the signal channels for …

Measuring The Role Of Inhibition In Auditory Discrimination In Mice, Tazima Nur

Graduate Theses and Dissertations

Understanding how inhibitory neurons affect sensory information processing in the cerebral cortex is an ongoing goal of both neuroscience and statistical physics research. In this master's thesis research project, an experimental system has been designed and built for studying how auditory dynamic range depends on inhibitory neurons, based on observations of mouse behavior. In this thesis, firstly, the topic of inhibition and information processing has been introduced. Then two papers related to inhibition and dynamic range has been reviewed in detail. One of the papers is an experimental work that analyzes the affect of inhibition on dynamic range. The other …

Atom-Based Geometrical Fingerprinting Of Conformal Two-Dimensional Materials, Mehrshad Mehboudi

Graduate Theses and Dissertations

The shape of two-dimensional materials plays a significant role on their chemical and physical properties. Two-dimensional materials are basic meshes that are formed by mesh points (vertices) given by atomic positions, and connecting lines (edges) between points given by chemical bonds. Therefore the study of local shape and geometry of two-dimensional materials is a fundamental prerequisite to investigate physical and chemical properties. Hereby the use of discrete geometry to discuss the shape of two-dimensional materials is initiated.

The local geometry of a surface embodied in 3D space is determined using four invariant numbers from the metric and curvature tensors which …

Evaluation Of Low-Tannin Grain Sorghum In Broiler Chicken Diets, Samantha Aniecia Shelton

Graduate Theses and Dissertations

Research trials were conducted to evaluate the effects of different levels of dietary grain sorghum on broiler live performance, carcass yield and shank (leg) and breast skin coloring. Iso-caloric diets were formulated where sorghum replaced corn at rates of 0% (control), 20, 40, 60, 80 and 100% for a total of 6 diets. For each of the two trials, 1500 Cobb 500 male broiler chicks were randomly allocated to 60 pens with 25 birds per pen (10 pens/diet) and grown to 46 days for the first research trial and 41 days for the second. There were no differences (P>.05) …

Protein Turnover In Broiler, Layers, And Broiler Breeders, Karen Vignale Lake

Graduate Theses and Dissertations

Protein turnover in skeletal tissue for broiler breeders has shown to increase at sexual maturity and then decline with increased egg production. Regarding broiler chickens the industry is facing two situations that need to be clarified: the appearance of white stripes in birds over 56 days of age and the positive effect in breast meat yield that supplementation of 25OH-D3 is causing. A series of studies were conducted to determine the effect of sexual maturity in protein turnover in broiler breeders and laying hens and to understand the effect of 25OHD3 in breast meat yield in broiler chickens and why …

Evaluation Of Phytate And Phytase Interactions And Phytase Phase-Feeding On Bird Performance, Bone Characteristics And Meat Quality In Young Growing Broilers, Chance L. Williams

Graduate Theses and Dissertations

Two trials were performed using one-day-old male Cobb x Cobb 500 broilers to determine how dietary phytate and phytase levels as well as phytase phase feeding impacted bird performance parameters, tibia characteristics, and malonaldehyde (MDA) content of the liver, breast and thigh tissues. The first experiment consisted of 1,008 birds randomly placed in 48 floor pens within two commercial broiler houses at the Applied Broiler Research Farm (ABRF; 21 birds per pen; 0.76 ft2 per bird). A 2 X 3 factorial design was used with two levels of dietary phytate (0.21 and 0.31 %) and three levels of phytase supplementation …

Enhancement Of Antimicrobial Activity Of Naturally Occuring Phenolic Compounds By Nano-Particle Mediated Delivery Against Listeria Monocytogenes, Escherichia Coli O157:H7, And Salmonella Typhimurium, Madhuram Ravichandran

Graduate Theses and Dissertations

Food-borne illnesses are of major concern in the U.S. and worldwide. Salmonella,Listeria,E. coli O157:H7 continue to be some of the major foodborne pathogens. Recurring recalls due to these pathogens demand critical antimicrobial strategies to decontaminate the food through its procession from farm to fork. In our study, we combined the effectiveness of naturally occurring phenolic compounds individually, with/ without ethylenediamine tetraacetic acid (EDTA) and/or Nisin and nanoparticle delivery to improve the antimicrobial potential of the compounds against Listeria monocytogenes (L.m.), Salmonella Typhimurium (S.T.), and Escherichia coli O157:H7 (E.c.), in brain …

The Response Of Cotton (Gossypium Hirsutum L.) To Slow Release Foliar Fertilization And The Effect Of Environment On Absorption, James Matthews Burke

Graduate Theses and Dissertations

In cotton production, nitrogen (N) is the most limiting nutrient and the demand is substantial. Foliar-N fertilization is regarded as an effective and environmentally sound method of supplying cotton with N during times of deficiency and high demand. In response to the potential benefits of the foliar-N fertilization of cotton, a myriad of foliar-N based fertilizers have been created; each with their own individual chemical technology and constitution. Experiments were performed with the objectives of examining the effects of the slow-release foliar-N fertilizer, Nitamin® (1) on the growth and development of field-grown cotton, (2) on uptake under various environmental conditions, …

Winter Field Pea As A Leguminous Cover Crop In Corn Production, Matthew Carroll Marsh

Graduate Theses and Dissertations

Leguminous cover crops, which fix nitrogen (N) from the atmosphere and add to the N content of the soil, have the potential to replace or partially replace commercial nitrogen fertilizers. In this experiment, field pea (Pisum arvense) was used as the leguminous cover crop in a conventional tilled corn (Zea mays) production system. In a 2-yr experiment (2008 and 2009), conducted at two locations in Arkansas, field pea was planted on half the field in the fall and allowed to grow until late April to early May. Field pea biomass was recorded, N content of biomass determined and then the …

Antibacterial Activity Of Commercially Available Plant Extracts On Selected Campylobacter Jejuni Strains, Divya Oppath Sivasankaran

Graduate Theses and Dissertations

Campylobacter jejuni is recognized as a leading cause of foodborne illness worldwide with approximately 850,000 cases per year in the United Sates. A total of 18 species of Campylobacter have been identified worldwide to date. Foodborne transmission of C. jejuni is mainly through the consumption of unpasteurized milk, contaminated poultry meat and water. C. jejuni can survive in very diverse environments under stressful conditions in human and animals which is different from the specific conditions and media required in laboratory experiments. There has been increased research in recent years to identify naturally occurring antibacterial agents to control and eliminate C. …

Alkaline Hydrolyzable-Nitrogen, Seeding Date, And Clay-Fixed Ammonium As Potential Indicators Of Rice Response To Nitrogen Fertilization In Arkansas, Anthony Michael Fulford

Graduate Theses and Dissertations

Several potential indicators of rice (Oryza sativa L.) response to nitrogen (N) fertilization include the soil<&rsquos>s alkaline hydrolyzable<&minus>N (AH<&minus>N) concentration, seeding date, and the soil<&rsquos>s clay<&minus>fixed NH₄<&ndash>N content. Three studies were conducted to: (1) correlate AH<&minus>N, determined using Illinois Soil Nitrogen Test (ISNT) or Nitrogen Soil Test for Rice (N<&minus>STaR), to plant parameters of interest and develop a fertilizer N rate calibration curve capable of predicting the 95% relative grain yield (RGY) fertilizer N rate for rice grown on clayey soils; (2) evaluate the influence of seeding date and N …

Screening Diverse Soybean Germplasm For Water-Logging Tolerance, John Franklin Carlin

Graduate Theses and Dissertations

Water-logging can be detrimental to soybean growth and development; effects range from chlorosis and stunting to yield loss and plant death. Soybean response to, and the effects of, water-logging are dependent on the growth-stage of the plant at the initiation of water-logging. The objectives of this study were to screen a diverse soybean germplasm collection for water-logging tolerance (WLT) at both the V5 and R1 growth stage and to develop a method to screen soybean for WLT in greenhouse. One hundred thirty five genotypes consisting of historical genotypes, PIs, drought and WLT tolerant breeding lines were screened for WLT in …

Assessing The Effectiveness Of Student Oriented Learning Outlines (Solos) In An Equine Classroom, Kathleen S. Jogan

Graduate Theses and Dissertations

This study determined if the use of the student oriented learning outline (SOLO) in a University of Arkansas equine production classroom had a positive influence in three areas: mastery of material taught, retention of material taught and voluntary positive student behaviors related to the use of course material. Thirty-one students who were enrolled in 2012 were in the non-SOLO group (control), and 25 students who were enrolled in 2013 were the SOLO group (treatment). Three separate units were taught to the treatment and control groups with only one difference: the treatment group was given a SOLO one week in advance …

Facing The Wreck: Death, Optimism, And The Fragmented Form, Rachael Marie Schaffner

Graduate Theses and Dissertations

Walter Benjamin described history as a winged angel who faces backwards, staring perpetually into the past as the violent winds of destiny carry him into the future (Illuminations). Despite a western, post-enlightenment myth of eternal progress, the wreckage of human contributions to history is clearly evident in our 21st-century understanding of anthropogenic impact on global ecology. In the context of these ecological crises (and the resulting political and economic questions), postmodern novels reveal a powerful ability to imagine different ways of living and interacting with the world. This thesis traces the relationship between fragmentation, death, and liminal experiences …

Correlated Response To Selection And Effects Of Pre-Slaughter Environment On Meat Quality In Broilers Divergently Selected For Muscle Color, Isaac David Harford

Graduate Theses and Dissertations

Two broiler lines divergently selected for high (HMC) and low (LMC) muscle lightness (L*) were formed from a random bred control line (RBC). After eight generations of selection, three experimental trials were conducted to investigate the correlated response to selection and effects of pre-slaughter environment on meat quality in all three lines.

In the first experiment, a total of 100 birds from each line were bled for blood chemistry analysis and were evaluated for meat quality the following day. The HMC line had higher fillet drip loss (DL), L*, heterophil to lymphocyte ratio (H:L), and platelet count (Plt), and lower …

Characteristics Of Agricultural Communications Undergraduate Programs, Morgan Michelle Large

Graduate Theses and Dissertations

This study was designed to characterize agricultural communications undergraduate programs nationwide. A total of 41 undergraduate agricultural communications programs were identified via the National ACT database, Internet searches, and previous academic program research. Objectives included creating an accounting of existing programs, a description of those programs, identifying trends in program demographics, curriculum development and identifying top programs. This study employed a census approach and used a mixed methods design. A mixed-methods survey instrument was used to collect the data. The survey included questions to gain both qualitative and quantitative data to meet this study's objectives. The quantitative data were analyzed …

Physiological Effects Of A Kettlebell Workout Versus A High-Resistance Circuit Workout, Brett Schreiber

Graduate Theses and Dissertations

Purpose: To compare the physiological effects of a single kettlebell workout to a high-resistance circuit workout in resistance-trained males. Methods: 12 resistance trained healthy males (age: 24 ± 2.97 years; height: 1.75 ± 0.064 m; body mass: 75.99 ± 8.46 kg) participated in this study. Participants had a familiarization visit and two subsequent experimental visits (kettlebell workout; circuit workout). The kettlebell workout consisted of 12-minutes of standardized kettlebell swings. The circuit workout consisted of three sets of 6 repetitions of smith machine squats, bench press, leg curl, and lat pulldown. Heart rate, rectal temperature, skin temperature, blood lactate, rating of …

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 …

Assessing Food Policy Options In Asia To Reduce Price Volatility Of Rice Market, Ranjitsinh Mane

Graduate Theses and Dissertations

Rice is a staple food in Asia and its prices at national and international levels are largely influenced by different policy actions of trading countries. The consequence of the 2008 food crisis was food riots and rationing of rice in many nations. The ASEAN Plus Three (APT) countries have adopted an institutional framework called ASEAN Plus Three Emergency Rice Reserves (APTERR) to address food security concerns of ASEAN countries that may arise due to climate change, supply chain disruptions or price speculation in the regional rice market. The RICEFLOW model is used to study the effectiveness of the strategic grain …

Balance And Power In Older Adults With And Without A History Of Falls, Stephanie Michelle Gray

Graduate Theses and Dissertations

The purpose of this study was to observe the differences between power and balance in older adults over the age of 65 with and without falls. A total of 62 community dwelling older adults between the ages of 65 and 92 participated in the study. Two groups consisted of 25 fallers and 37 non-fallers. No statistical differences were found between groups on age, height, weight, or BMI. Testing included the Berg Balance Scale (BBS) to test balance, the Tendo Weightlifting Analyzer (TWA) during a sit-to-stand to test lower body power, and the Physical Activity Scale for the Elderly (PASE) to …

Effects Of Breathing Cool Air During Cycling Exercise In The Heat, Christian B. Ridings

Graduate Theses and Dissertations

INTRODUCTION: The purpose of this study was to establish the ability of the Core Cooler device to prevent rises in physiological heat strain of trained male cyclists during cycling exercise in the heat. METHODS: 15 healthy male cyclists cycled at 50-70% VO2max for 75 minutes in a heat chamber of 31°C & 55% RH while breathing through the Core Cooler device under three different conditions: 1:4 ratio without ice termed control (CN), 1:4 ratio with ice termed low intermittent (LI), and at 1:1 ratio with ice termed high intermittent (HI). Data collected every 15 minutes assessing intestinal temperature (TGI), heart …

Evaluating Green Stink Bug Damage And Insect Abundance In Edamame, Benjamin Carroll Thrash

Graduate Theses and Dissertations

Edamame are an emerging crop in Arkansas, with 2013 planting estimates at 680 hectares. Although edamame are the same species as conventional soybeans grown in Arkansas, differences in use, maturity, and harvest may require creation and implementation of insect pest management approaches that differ from those used in conventional soybean production systems in order for a quality crop to be produced. Studies were conducted to determine a green stink bug damage-density relationship for edamame. Cages were used to confine green stink bugs on field-planted edamame at densities of 0, 2, 6, or 12 green stink bugs per cage (0, 0.55, …