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Influences Of Contexts On Consumers' Visual Attention Towards Food Images: Eye-Tracking Studies, Baoyue Zhang Dec 2014

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 Dec 2014

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 …


Screening Diverse Soybean Germplasm For Water-Logging Tolerance, John Franklin Carlin Dec 2014

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 …


Nitrogen Management Practices And Colored Plastic Mulch Films Affecting Spider Mites And Aphids On Winter Strawberry In A High Tunnel, Kevin Philip Durden Aug 2014

Nitrogen Management Practices And Colored Plastic Mulch Films Affecting Spider Mites And Aphids On Winter Strawberry In A High Tunnel, Kevin Philip Durden

Graduate Theses and Dissertations

Off season high tunnel strawberry production has the potential to augment income for Arkansas fruit growers during an unproductive time of the year, however management guidelines do not exist. At the University of Arkansas Agricultural Research and Extension Center in Fayetteville, AR studies were conducted to evaluate the effects of four nitrogen (46-0-0 urea fertilizer) fertigation rates (0.75, 0.50, 0.25, 0.0 kg N/day/ha) and red or black colored plastic mulch films on densities of twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae), numbers of parasitized cotton aphids, and fruit yield weight. Foliar and …


Assessing Food Policy Options In Asia To Reduce Price Volatility Of Rice Market, Ranjitsinh Mane Aug 2014

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 …


Effect Of Supplemental Trace Mineral (Zinc, Copper, And Manganese) Source On Growth Performance, Morbidity, And Trace Mineral Status In Beef Cattle, Anthony Ryan Aug 2014

Effect Of Supplemental Trace Mineral (Zinc, Copper, And Manganese) Source On Growth Performance, Morbidity, And Trace Mineral Status In Beef Cattle, Anthony Ryan

Graduate Theses and Dissertations

A series of studies were conducted to determine the effect of supplemental trace mineral source on growth performance, morbidity, and trace mineral status in growing beef cattle. The first experiment evaluated supplemental trace minerals from sulfate, organic, or hydroxy sources on growth performance and morbidity. Crossbreed beef calves were assigned to 1 of 3 treatments consisting of supplemental zinc (360 mg/d), copper (125 mg/d), and manganese (200 mg/d) from inorganic, organic, or hydroxy sources fed daily over a 42 to 45-d backgrounding phase. After removal of chronic and dead calves from the data set, trace mineral source had no effect …


Influence Of Steroids And Gonadotropins On Reproduction In Beef Cattle, Thomas L. Devine Aug 2014

Influence Of Steroids And Gonadotropins On Reproduction In Beef Cattle, Thomas L. Devine

Graduate Theses and Dissertations

The objective of this thesis was to evaluate the influence of steroids and gonadotropins on reproduction in beef cattle. In experiment 1, beef heifers were used to determine the influence of growth-promoting implants on growth, reproductive development, estrous behavior, and pregnancy rate. Heifers were assigned to 1 of 4 implant treatment groups: control (CON); trenbolone acetate (TBA); trenbolone acetate plus estradiol (TBA+E2) or zeranol (ZER). Heifers were implanted once, A.I. and exposed to bull during this experiment. Body weight, BCS, HH, RTS, estrous behavior and pregnancy data were collected throughout this experiment. Average daily gain of heifers was greater for …


The Effects Of Combining Looping, Cognitively Guided Instruction, And Ethnicity: How They Can Collectively Improve Academic Achievement, Matthew Brandon Wilson Aug 2014

The Effects Of Combining Looping, Cognitively Guided Instruction, And Ethnicity: How They Can Collectively Improve Academic Achievement, Matthew Brandon Wilson

Graduate Theses and Dissertations

The purpose of this quantitative study is to gain an understanding of the powerful instructional potential of combining the practice of looping, Cognitively Guided Instruction (CGI) professional development strategies, and the impact these practices have in addition to ethnicity in elementary education. The study focused on research questions pertaining to student's Measure of Academic Progress (MAP) scores and the implementation of looping, CGI strategies, and how ethnicity impacted student achievement.

This study emphasizes two types of statistical tests to determine how significant CGI and looping practices impacted growth in mathematics on the MAP test for different ethnic groups. A Chi-Square …


Evaluating Green Stink Bug Damage And Insect Abundance In Edamame, Benjamin Carroll Thrash Aug 2014

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, …


The Effect Of Leucine Supplementation On Biomarkers Of Mitochondrial Biogenesis And Protein Synthesis In Soleus Muscle Of Rats Fed A High-Fat Diet, Gina Davis Aug 2014

The Effect Of Leucine Supplementation On Biomarkers Of Mitochondrial Biogenesis And Protein Synthesis In Soleus Muscle Of Rats Fed A High-Fat Diet, Gina Davis

Graduate Theses and Dissertations

Mitochondrial dysfunction is a contributing factor to the advancement of various diseases including obesity, diabetes, and cardiovascular disease. Impairment in mitochondria brings about a diminished mitochondrial number and oxidative capacity. Leucine is known to stimulate muscle protein synthesis through transcription and translation of nuclear DNA leading to increases in mitochondrial biogenesis and fatty acid oxidation. However, the effects of leucine on anabolic factors of the mitochondrial genome, during catabolic conditions are not known. PURPOSE: To determine if leucine supplementation alters the negative effects of a high fat (60%) diet (HFD) on the mitochondrial genome by measuring the gene expression of …


Correlated Response To Selection And Effects Of Pre-Slaughter Environment On Meat Quality In Broilers Divergently Selected For Muscle Color, Isaac David Harford Aug 2014

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 …


Identification Of Quantitative Trait Loci / Genes For Low-Stachyose And High-Sucrose Content In Soybean Seeds, Sandra Liliana Florez Palacios Aug 2014

Identification Of Quantitative Trait Loci / Genes For Low-Stachyose And High-Sucrose Content In Soybean Seeds, Sandra Liliana Florez Palacios

Graduate Theses and Dissertations

Seed carbohydrate content is an important aspect in breeding for food-grade soybeans commercialized in the soyfood market. Sucrose and stachyose are the primary carbohydrates in soybean seed. Sucrose affects the quality and taste of various soyfoods such as tofu, soymilk, and natto; however, consumption of soy-based products with high stachyose concentrations can cause diarrhea and flatulence. A mutant line (V99-5089) with high-sucrose and low-stachyose has been identified. The objectives of this research were: 1) to identify sucrose QTLs in a F2-derived mapping population; 2) to investigate the genetic relationship between two low-stachyose sources, V99-5089 and the germplasm line PI200508; and …


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 …


Gender, Humor And Quality Of Life In Workplace Sitcoms: A Content Analysis Examining Agency In Post-Recession Situation Comedies, Gwendolyn Logan Bost Aug 2014

Gender, Humor And Quality Of Life In Workplace Sitcoms: A Content Analysis Examining Agency In Post-Recession Situation Comedies, Gwendolyn Logan Bost

Graduate Theses and Dissertations

This study used content analysis to analyze gender representations in post-recession workplace sitcoms using a typology developed using Maslow's Hierarchy of needs. 100 episodes of programming were analyzed by five graduate researchers for a total of 2579 cases. Though men dominated the sample, results were dissimilar from previous findings within some of the literature on televised representations of gender. Findings indicated that need type for most commonly expressed needs were split fairly evenly by gender, but that less expressed needs were more polarized with regard to gender representation. Women also met their own needs more than men did, and had …


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 …


Effects Of Breathing Cool Air During Cycling Exercise In The Heat, Christian B. Ridings Aug 2014

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 …


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 …


Relationship Between 1,3-Dichloropropene And Nitrogen Fertility In Cotton In The Presence Of Root-Knot And Reniform Nematodes, Amanda Michelle Greer May 2014

Relationship Between 1,3-Dichloropropene And Nitrogen Fertility In Cotton In The Presence Of Root-Knot And Reniform Nematodes, Amanda Michelle Greer

Graduate Theses and Dissertations

The use of soil fumigation for nematode management in cotton (Gossypium hirsutum) has become increasingly popular in recent years in the absence of effective resistant cultivars. While soil fumigation is relatively expensive, lint yields have consistently been improved to make this practice profitable in fields with severe nematode pressure. Growers in southern Arkansas have observed changes in cotton growth patterns when severely infested fields are fumigated. The most noticeable change has been excessive (rank) growth resulting in an increased need for growth regulators, especially where the nitrogen fertilization exceeds standard recommendations. Field studies were conducted between 2007 and 2010 to …


Health, Nutrition, And Disease In Rural Northern Jordan: A Study Of Enamel Defects Related To Childhood Stress In Skeletal Samples From The Bronze Age To The Byzantine Period, Teresa Veronica Wilson May 2014

Health, Nutrition, And Disease In Rural Northern Jordan: A Study Of Enamel Defects Related To Childhood Stress In Skeletal Samples From The Bronze Age To The Byzantine Period, Teresa Veronica Wilson

Graduate Theses and Dissertations

Northern Jordan has seen periods of climate change, political transformation, and economic prosperity between the Late Bronze Age to the end of the Byzantine period. This research tests the assumption that the rural agricultural communities of this region were undernourished by examining the dentition for periodic childhood stress. Canine teeth from five sites (Ya'amun, Sa'ad, Yasileh, Natfieh, and Waqqas) that covered the time periods in question were collected to study overall quality of life.

The teeth were thin-sectioned and examined under a light microscope. Digital micrographs were made of the thin-sectioned teeth in order to record the number and location …


Improving Lamb Performance With Sericea Lespedeza And Molybdenum, Mohan Acharya May 2014

Improving Lamb Performance With Sericea Lespedeza And Molybdenum, Mohan Acharya

Graduate Theses and Dissertations

The objective of this research was to find the effect of prolonged feeding of sericea lespedeza (SL) supplemented with sodium molybdate on changes in body weight, serum and liver concentration of trace minerals (TM), hematology, serum biochemistry, and gastrointestinal parasites. Thirty ram lambs (Katahdin and ¾ Katahdin × ¼ Romanov) were weaned; blood, liver, and fecal samples were collected and signs of internal parasitic infection on lambs were recorded. Lambs were supplemented with 900 g of alfalfa (n = 10; CON) or SL (n = 20) based supplement for 103 d. Within the SL group, half of the lambs were …


Estimating Nitrogen Fixation Rates, Importance, And Short-Term Efficiency In Small, Temperate Reservoirs Using Delta15n Techniques, Bryant Christopher Baker May 2014

Estimating Nitrogen Fixation Rates, Importance, And Short-Term Efficiency In Small, Temperate Reservoirs Using Delta15n Techniques, Bryant Christopher Baker

Graduate Theses and Dissertations

Nitrogen (N2) fixation can give certain species of cyanobacteria a competitive advantage in lake and reservoir phytoplankton. These species of cyanobacteria, along with others that cannot fix N2, can form toxic compounds that impair water quality when present in high concentrations. N2 fixation rates may be substantial in small (< 1.0 km2), temperate reservoirs since these systems experience thermal stratification and often nitrogen (N) limitation throughout a substantial proportion of the year. However, the effects of N2 fixation on N cycling, alleviation of short-term N limitation, and water quality are not well-understood. A mesocosm experiment and ecosystem-scale observational study were conducted to 1) determine the efficiency of N2 fixation under varying N relative to phosphorus (P) supply, 2) examine the effects of N2 fixation on autotrophic biomass accumulation and microcystin production, and 3) measure N2 fixation rates and importance to autotrophic N demand and zooplankton N assimilation. Results of the mesocosm experiment indicated that N2 fixation was increased at low N:P supply under high P. However, N2 fixation was inefficient at alleviating N limitation when fixed N was the primary source of N. Additionally, microcystin production occurred only at high N:P supply when N2 fixation was low, indicating that reducing external N inputs may have a positive effect on water quality. Results of whole-reservoir determination of N2 fixation using seston δ15N natural abundances indicated that N2 fixation rates throughout the warm season were substantial and influenced by water temperature. Annual N2 fixation rates ranged from 2.2 - 6.6 g N m-2 yr-1, and contributed up to 19% of the annual autotrophic N demand. Zooplankton were assimilating fixed N in most of the study reservoirs, representing a possible mechanism of ecosystem fixed N retention. Collectively, these results suggest that N2 fixation plays a substantial role in N cycling in small, temperate reservoirs, but likely cannot alleviate short-term N limitation.


Efficacy Of Rice Insecticide Seed Treatments At Selected Nitrogen Rates For Control Of The Rice Water Weevil, Lissorhoptrus Oryzophilus Kuschel, Mallory Elise Everett May 2014

Efficacy Of Rice Insecticide Seed Treatments At Selected Nitrogen Rates For Control Of The Rice Water Weevil, Lissorhoptrus Oryzophilus Kuschel, Mallory Elise Everett

Graduate Theses and Dissertations

Seed-applied insecticides are the standard control method used to prevent rice water weevil (Lissorhoptrus oryzophilus Kuschel) injury to rice (Oryza sativa L.) roots, and often results in greater yields than rice that receives no seed-applied insecticide. Yield increases from seed-applied insecticides often occur even when insect pressure is low and should not cause yield loss. The research objective was to evaluate the effect of urea-nitrogen rate and seed-applied insecticide on number of rice water weevil larvae, nitrogen uptake and rice grain yield. Six trials were conducted at the Pine Tree Research Station (PTRS) and the Rice Research Extension Center (RREC) …


Effect Of An After-School Garden Club Program On Elementary Students, Maggie Caroline Mcgriff May 2014

Effect Of An After-School Garden Club Program On Elementary Students, Maggie Caroline Mcgriff

Graduate Theses and Dissertations

The purpose of this study was to determine if three elementary school garden club programs influenced students' attitudes and behaviors regarding fruit and vegetable consumption. Both quantitative and qualitative data collection and analysis took place, in the form of pretest and posttest questionnaires as well as participant interviews. Overall, non-significant results were found in the quantitative portion of the study, which led the researcher to determine that the garden club program had no significant effect on the participants regarding perceptions of fruit and vegetable consumption. The overall non-significant differences found before and after the garden club intervention programs could lead …


Poultry Performance And Food Safety Impacts Of Selected Organic Acids And Probiotics, Anita Menconi May 2014

Poultry Performance And Food Safety Impacts Of Selected Organic Acids And Probiotics, Anita Menconi

Graduate Theses and Dissertations

Improving production parameters and controlling foodborne pathogens have been challenges to the poultry industry. Salmonella has been the most common bacterial pathogen in laboratory confirmed foodborne illness cases, and contaminated poultry and poultry products have been identified as the most important source of transmission of Salmonella to humans. Therefore, research on effective interventions to reduce Salmonella transmission at the poultry production level has gained attention. Initially, a series of studies was conducted to evaluate the use of selected organic acids in controlling foodborne pathogens and improving poultry performance. Then, the characterization and application of lactic acid bacteria and Bacillus spp. …


Stability Of Nano-Encapsulated Rice Bran Derived Bioactive Pentapeptide In Apple Juice, Fatima Mohammed Alessa May 2014

Stability Of Nano-Encapsulated Rice Bran Derived Bioactive Pentapeptide In Apple Juice, Fatima Mohammed Alessa

Graduate Theses and Dissertations

Cereal grains and their components derived Bioactive compounds such as rice bran can promote health and can be derived from Rice bran contains 12-20 % protein and could be a good source for extracting bioactive peptides. A pentapeptide with a secqunce of amino acids Glu-Gln-Arg-Pro-Arg (EQRPR) has been prepared from heat stablized defatted rice bran (HDRB) and has demonstrated anti-cancer proprerties in-vitro. This bioactive pentapeptide can thus be used as a nutraceutical by incorporating it into a suitable food system. Fruit juces can be vehicles to incorporate this pentapeptide. Fruit juices contribute to about 60% of the consumed beverages in …


A Framework For Constructing Serious Games, Taylor Glen Yust May 2014

A Framework For Constructing Serious Games, Taylor Glen Yust

Graduate Theses and Dissertations

Communicating ideas and knowledge through serious games is a trend that is currently gaining in popularity. However, at present, there is a distinct lack of a game development methodology that takes a critical approach to transforming information into gameplay. This thesis presents a framework that can be followed to construct compelling serious games that are effective at transferring knowledge to the player. This is accomplished through an analysis of atomic knowledge items and their relationships to one another, followed by a meaningful and synergetic implementation of these ideas at a foundational mechanics level.

This thesis also describes the development of …


Queer Tastes: An Exploration Of Food And Sexuality In Southern Lesbian Literature, Jacqueline Kristine Lawrence May 2014

Queer Tastes: An Exploration Of Food And Sexuality In Southern Lesbian Literature, Jacqueline Kristine Lawrence

Graduate Theses and Dissertations

Southern identities are undoubtedly influenced by the region's foodways. However, the South tends to neglect and even to negate certain peoples and their identities. Women, especially lesbians, are often silenced within southern literature. Where Tennessee Williams used literature to bridge gaps between gay men and the South, southern lesbian literature severely lacks a traceable history of such connections. The principal objective of this thesis is to explore the ways in which southern lesbians manipulate food metaphors to describe their sexual desires and identities. This thesis only begins to lay out a history of southern lesbian literature as many lesbian writers …


Impact Of Early Infestation Of Two-Spotted Spider Mites (Tetranychus Urticae) On Cotton Growth And Yield, Luis Orellana Jimenez May 2014

Impact Of Early Infestation Of Two-Spotted Spider Mites (Tetranychus Urticae) On Cotton Growth And Yield, Luis Orellana Jimenez

Graduate Theses and Dissertations

Two-spotted spider mites (Tetranychus urticae Koch, 1836) are pests of vegetables, ornamentals, and row crops around the world. Two-spotted spider mites have become an important long-season pests of cotton, causing injury to cotton from an early vegetative stage. In the past eight years, Arkansas cotton acreage treated for spider mites has more than doubled and most of the increase has been attributed to early season infestations. Yield losses of up to 30% have been observed in other studies where spider mite infestation started at third true leaf. Because of the apparent change in this pest's population dynamics, particularly at …


Identifying, Monitoring, Quantifying And Converting Algae To Bio-Fuels In Bio-Reactors, Alice C. Jernigan May 2014

Identifying, Monitoring, Quantifying And Converting Algae To Bio-Fuels In Bio-Reactors, Alice C. Jernigan

Graduate Theses and Dissertations

Growing algae as a source for bio-fuels has become an area of interest due to concerns about global warming and the reliability and ecology of the production of fossil fuels. Dried algae harvested from a pilot water quality improvement technology at the Rockaway Wastewater Treatment Facility in New York were examined as a source of carbohydrates and lipids for the production of bio-fuels in bio-reactors. The length of storage time, storage conditions, sugar and lipid extraction processes, and fuel production were studied. The results show that if the algae is stored dry (0.015 g/g algae even after a year in …


Leaching Characteristics Of Selenium From Coal Fly Ash, Mark Allen Cantrell May 2014

Leaching Characteristics Of Selenium From Coal Fly Ash, Mark Allen Cantrell

Graduate Theses and Dissertations

Selenium (Se) contamination can be a potential groundwater concern near un-lined coal ash landfills. Out of all the Environmental Protection Agency (EPA) priority and non-priority pollutants, Se has the narrowest range between what is considered beneficial and detrimental for aquatic and terrestrial organisms. The effects of ash type (i.e., fresh and weathered), water-extractant type (i.e., deionized water, rainwater, and groundwater), and extraction time (i.e., 2- and 6-hours) on Se, arsenic (As), and chromium (Cr) concentrations were investigated from Class C, subbituminous coal fly ash produced at the Flint Creek Power Plant located in Benton County, AR. Water-extractable Se concentrations differed …