Life Sciences Commons^™

Flexible Microelectrode-Based Impedance Immunosensor For Rapid Detection Of E. Coli O157:H7, Sonatan Kumar Biswas

Graduate Theses and Dissertations

Abstract Food contamination poses a significant threat to public health, the economy, and human health worldwide, occurring at any stage of the food supply chain, from farm to fork. Escherichia coli 0157:H7, recognized as one of the principal causes of foodborne illness, poses a considerable risk to food safety. The primary objective of this investigation is to devise a flexible microelectrode-based immunosensor capable of swiftly identifying E. coli O157:H7 cells without the need for incubation in a pure culture environment. In the development of the biosensor, the gold electrode (composed of 50% Au) underwent an initial coating process involving 2-aminoethanethiol/cysteamine, …

Crispr-Cas9 Integration Of Salmon Elovl2 In Zebrafish Enhances Lc-Pufa Biosynthesis And Growth Across Diets, Waleed Sami J. Al-Bachry

Graduate Theses and Dissertations

Fish are a rich source of EPA and DHA, which are well-known long-chain polyunsaturated fatty acids (LC-PUFAs). The sustainable production of these essential fatty acids poses significant challenges, mainly due to our dependence on marine fish and certain nuts. CRISPR-Cas system was utilized to insert the elongation of long-chain fatty acids-like2 (Elovl2) gene from Salmo salar into Danio rerio. Elovl2 was introduced at 10-15-minute post-fertilization, and successful integration confirmed by PCR genotyping, sequencing and expression of EGFP. Approximately 67% of injected embryos successfully exhibited EGFP and sequence results verified the gene integration of Salmo salar Elovl2 at the first start …

Variation In Stress Response Regulation Across Natural Isolates Of Saccharomyces Cerevisiae, Crystal Christine Crook

Graduate Theses and Dissertations

The stress response of Saccharomyces cerevisiae is a valuable area of study for understanding cellular adaptation mechanisms that govern survival in fluctuating environments. This dissertation investigates stress response regulation in yeast through the roles of Hog1 mitogen-activated protein kinase (MAPK) and the post-transcriptional regulator Mkt1, a key post-transcriptional regulator, in diverse wild yeast isolates. Hog1 is traditionally known for its central role in osmotic stress regulation in the high-osmolarity glycerol (HOG) pathway. This study expands the functional scope of Hog1 to include oxidative and ethanol-induced stress responses.

In parallel, we investigate post-transcriptional regulation of stress responses by the Mkt1 interactome, …

The Efficacy Of Foam-Based Hand Sanitizers For The Control Of Enveloped And Non-Enveloped Virus Transmission, Francis Torko

Graduate Theses and Dissertations

Infectious disease transmission due to viruses such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), influenza virus, human noroviruses (HuNoV), and hepatitis A, can occur via person-to-person contact or contaminated surfaces. Effective hand hygiene, including hand washing and use of hand sanitizers, is considered a critical tool for the control of infectious disease transmission, as recommended by the United States Centers for Disease Control and Prevention and the World Health Organization. However, while research on hand washing efficacy is well-documented, research on hand sanitizer efficacy, particularly for foam-based products, remains limited. This research addressed critical gaps in the area of …

Fish Cultivation In Fallow Season Rice Fields: Effects On Landscape Methane Emissions, Samuel Carroll

Graduate Theses and Dissertations

Co-cultivation of aquatic animals and rice in the same field is a fairly common practice in various parts of the world, with a number of well-established agro-ecological benefits, such as decreasing the need for chemical pesticides and fertilizers, increasing soil organic matter, and reducing the land area needed for agricultural production. One area of environmental concern in rice production is greenhouse gas emissions. Rice production contributes about 10% of global anthropogenic methane (CH₄) emissions. Currently around 27.5% of Arkansas rice fields are flooded in the winter, which can increase CH₄ emissions in the fallow season by 45% …

Implications Of Acetylation And Phosphorylation On Metabolic Enzymes, Nour Fatema

Graduate Theses and Dissertations

All living things depend on glycolysis and the TCA cycle for energy production and metabolic control. Post-translational modifications (PTMs) such as acetylation and phosphorylation, which can change enzyme activity, substrate binding, and overall metabolic balance, tightly regulate these pathways. Diseases like cancer and metabolic problems are associated with disruptions in these alterations.

Serine phosphorylation and lysine acetylation are two of the many PTMs that are evolutionarily conserved processes that alter protein function. Previously thought to be a static histone alteration, acetylation is now understood to be a dynamic regulator of metabolic enzymes that modifies contacts, charge, and conformation. In response …

Developing Custom Fertilizer Strategies Recirculating Hydroponic Systems, Joshua Bryan Tebow

Graduate Theses and Dissertations

Hydroponic systems recirculate nutrient solution to reduce the amount of water used in leafy green production. However, the rootzone of the nutrient solution is complex and influenced by interacting factors such as plant uptake demand, irrigation water quality, supplied fertilizer salts and nutrient concentrations, environmental conditions, and injection of mineral acids/bases to control solution pH. A common strategy for managing nutrients in commercial production is to select a hydroponic solution formulation (i.e. recipe) to supply and maintain a target pH and electrical conductivity (EC) in the recirculating solution over time by automatic injection of mineral acids/bases and concentrated fertilizer stock …

Fixed-Time Artificial Insemination Protocols Using Pre-Synchronization In Suckled Beef Cows, Wyatt Eugene Weber

Graduate Theses and Dissertations

Adoption of artificial insemination by beef producers has been limited within the United States. Estrous synchronization (ES) for fixed-time artificial insemination (FTAI) has been one of the most effective ways to implement artificial insemination into beef production systems, but its efficiency has primarily been restrained by the dependency on the effectiveness of the initial gonadotropin releasing hormone (GnRH) injection in many FTAI protocols. The hypotheses of these studies were to determine practical methods of pre-synchronization to improve current FTAI protocols, ultimately increasing beef herd reproductive performance. The objective was to evaluate the use of prostaglandin F2α (PGF) and progesterone (P4) …

Livestock Risk Protection Basis Risk For Feeder Cattle, Bryce Anderson

Graduate Theses and Dissertations

Recent government subsidies make livestock risk protection (LRP) insurance an affordable price risk management tool for many U.S. cattle producers. LRP insurance triggers a loss when the Chicago Mercantile Exchange (CME) Feeder Cattle Index falls below the selected coverage price. The CME Feeder Cattle Index is a 7-day weighted average of feeder cattle prices in 12 states. This paper determines if LRP policy holders who produce feeder cattle in states whose feeder cattle prices are not included in the CME Feeder Cattle Index are exposed to excess basis risk. To do this, we use a hedonic regression model to determine …

Evolutionarily Conserved Functions Of The Gene Frazzled In Midline Axon Guidance In Drosophila Melanogaster And Tribolium Castaneum., Piyasi Ghosh

Graduate Theses and Dissertations

Axon guidance in bilaterians is often controlled by various signaling pathways in the nervous system, which determine the fate of the axons if they cross the midline or not. One such pathway involved is the ligand-receptor pair Netrin (Net) and Frazzled (Fra), which is also known as the attractive pathway that promotes midline crossing axons in insects and other bilaterians. Orthologs of the pathway ligand Netrins and their receptors Frazzled [Fra] in insects and Deleted in Colorectal cancer [DCC] in vertebrates are widely conserved in bilaterians. How well these regulatory roles of the protein are conserved is poorly understood. In …

Bacterial Chondronecrosis With Osteomyelitis In Broiler Chickens: Experimental Lameness And Additive Probiotic Treatments, Amanda Anthney

Graduate Theses and Dissertations

With the global population already surpassing 8.2 billion and expected to reach 9.7 billion by 2050, the poultry industry has seen a surge in demand due to its unmatched efficiency and affordability for consumers across the globe. Selective breeding and quality nutrition developments since the industry's commercialization have allowed producers to grow broilers up to 7 pounds by market age. While this extraordinarily efficient process has allowed quality poultry products to be available worldwide, the modern-day broiler has developed a multitude of musculoskeletal issues. Due to the lack of integral skeletal development to match the rapid production of muscle tissue, …

Investigating Evolution Through The Lens Of Ai-Driven Protein Exploration And Phylogenetic Modeling, Mataya Duncan

Graduate Theses and Dissertations

Recent advances in computational biology, artificial intelligence, and sequencing technologies have enabled new perspectives for addressing longstanding questions in evolutionary biology. Increased computational power has made large-scale simulations feasible for investigating diverse aspects of evolutionary and phylogenetic modeling. Similarly, deep learning algorithms now allow for the prediction of reasonably accurate tertiary protein structures, unlocking the potential for investigating diversity and evolution of protein structure across a broad range of organisms. This thesis presents two studies that target different aspects of evolutionary inference from unique perspectives. Yet, the share an overarching goal of presenting new perspectives on the evolutionary basis of …

Bacterial Chondronecrosis With Osteomyelitis In Broilers: Etiology And Selected Mitigation Measures, Khawla Saud Alharbi

Graduate Theses and Dissertations

Bacterial chondronecrosis with osteomyelitis (BCO) is the predominant cause of lameness in broiler chickens. It mainly impacts broiler production and animal welfare, causing substantial financial losses accounting for 1- 2% due to bird condemnations at the marketing age. Remediating BCO lameness disease demands investigating its causes using appropriate models and evaluating preventive measures, such as enhancing epithelial tissue health and tight junction integrity in the digestive and respiratory tract, strengthening immune functions, and improving bone strength. Therefore, the objectives of this dissertation were to 1) study predisposing factors for BCO lameness by investigating the effects of deoxynivalenol (DON) and fumonisin …

Yield And Economics Following 5 Years Of Integrated Weed Management In Cotton, Amar Godar, Jason K. Norseworthy, L. Tom Barber, Roger Farr, Ty Smith

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

The implementation of integrated weed management (IWM) practices in conventional management systems involves additional costs and can influence both short-term and long-term cotton (Gossypium hirsutum L.) yields, ultimately affecting economic viability. This study, conducted from fall 2018 to fall 2023 near Marianna, AR, evaluated four IWM practices in a large-plot, fixed-plot factorial design: zero tolerance for weed seed rain, soil inversion deep tillage every third year in the fall, a preplant terminated cereal rye cover crop, and dicamba-resistant cotton technology. Long-term economic impacts were assessed using the 5-year average cost-adjusted yield, with the base program (excluding all IWM practices) serving …

Characterization Of 3d Printed Microdialysis Probes For Solute Recovery And Non-Specific Adsorption, Bailey N. Scoggins

Chemistry & Biochemistry Undergraduate Honors Theses

Microdialysis is an important sampling technique that has uses in a wide range of disciplines, such as neuroscience and pharmacokinetics. 3D printing aims to address adaptability and customization issues that are present in standard “off-the-shelf” microdialysis probes. This work aims to lay the groundwork for characterizing a 3D printed microdialysis probe designed at the University of Arkansas. One experiment involved measuring solute recovery of caffeine as a function of flow rate of a standard CMA 11 probe to assess its membrane performance. The other goal was to learn about non-specific adsorption tendencies of enzymes (i.e., to what degree proteins stick …

Characterization Of Streptococcus Gallolyticus: An Emerging Pathogen Causing Turkey Streptococcosis, Latasha S. Gray

Graduate Theses and Dissertations

During the past five years, there has been an increased occurrence of Streptococcus gallolyticus in young turkey poults. This emerging pathogen previously affected turkey flocks without any indication of disease prior to acute mortality. However, recently there has been two cases of neurological presentation associated with S. gallolyticus subsp. pasteurianus that are unique to traditional disease presentation in turkey poults. The objectives of the present dissertation were to compile data associated with the two neurological cases and compare different S. gallolyticus strains as well as pathogenic Enterococcus cecorum to the neurological strains. The two neurological cases occurred between July and …

Utility Of John Deere's See & Spray Ultimate In Southern U.S. Row Crops, Tristen Avent

Graduate Theses and Dissertations

Row crop producers across the southern United States are observing a boom in technological advancement to improve operational efficiency. Additionally, environmental concerns and reduced profit margins drive the adoption of targeted pesticide application technologies like the John Deere See & Spray. This technology is relatively new, introduced in 2022, and producers need more insight into the shortcomings, potential herbicide savings, and the economic benefits of adoption. Since 2021, research has been conducted in Keiser, AR, with additional collaborative projects in Mississippi, North Carolina, Indiana, and Illinois. Five different objectives were addressed in this research: 1) to determine the impact of …

Comparisons Between Traditional And Gluten-Free Cookies In Sensory Attributes, Acceptance, And Evoked Emotions, Eniola Ola

Graduate Theses and Dissertations

The rise in food allergies and intolerances, notably conditions like Celiac disease, as well as a general shift of consumers to a more health-conscious lifestyle has significantly increased the demand for gluten-free products. Consumers increasingly seek gluten-free products, yet these alternatives often face challenges in replicating the sensory qualities of traditional gluten-containing foods. This study explores the sensory attributes, emotional responses, and labeling impacts on consumer perception of gluten-free and gluten-containing cookies. The main objective of this thesis was to address the gap in research on sensory evaluation of gluten free foods, specifically in terms of commercially available products. The …

Variations In Sensory And Emotional Responses To Gluten-Containing And Gluten-Free Cookie Products Under Blind And Labeled Conditions, Eniola Ola, Han-Seok Seo

Food Science Faculty Publications and Presentations

The gluten-free food market is expanding rapidly. However, consumer acceptance and emotional responses to gluten-free food, especially commercially available products, have received relatively underexplored. This study aimed to determine how consumer perceptions, acceptance, and emotional responses differ between gluten-containing (C) and gluten-free (F) chocolate chip cookies from three brands under both blind and labeled conditions. In the labeled condition, 84 participants without celiac disease evaluated 3 F cookies labeled "gluten-free" and 3 C cookies presented without claims on a plain white card. In the blind condition, they tested the six cookies without labels. Participants provided hedonic ratings, Just-About-Right (JAR) ratings, …

Cover Crop Effects On Greenhouse Gas Emissions And Global Warming Potential In Furrow-Irrigated Corn In The Lower Mississippi River Valley, Diego Della Lunga, Kristofor Brye, Michael J. Mulvaney, Mike Daniels, Tabata De Oliveira, Beth Baker, Timothy Bradford Jr, Chandler M. Arel

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Corn (Zea mays) production systems are described as high risk for emissions of greenhouse gases (GHG) due to large fertilizer inputs. Conservation practices, such as cover crop (CC), can limit the effects of agricultural activities on GHGs while increasing carbon and nitrogen storage. The objective of the study was to assess the effects of cover crops, i.e., with CC and no-CC, on GHG (i.e., CO2, CH4, and N2O) emissions and global warming potential (GWP) in furrow-irrigated corn in the Lower Mississippi River Valley. Gas sampling was conducted with an automated system that measured GHGs four times daily during the 2024 …

A Systematic Review And Meta-Analysis Of Chemical Sanitizer Efficacy Against Biofilms Of Listeria Monocytogenes, Salmonella Enterica, And Stec On Food Processing Surfaces, Allyson N. Hamilton, Sarah L. Jones, Christopher A. Baker, Xinya Liang, Adam Siepielski, Ashlynn Robinson, Gayatri R. Dhulappanavar, Kristen E. Gibson

Food Science Faculty Publications and Presentations

Chemical sanitizers are applied to food processing surfaces to inactivate bacterial pathogens. Pathogen type, surface type along with sanitizer type, concentration, and contact time are important factors potentially impacting sanitation efficacy. Numerous studies on chemical agents and lab-generated biofilms have been published; however, cross-study comparisons can be difficult. A systematic literature review (SLR) and meta-analysis were conducted to evaluate chemical sanitizer efficacy against Listeria monocytogenes, Salmonella spp., and Shiga toxin-producing Escherichia coli (STEC) within lab-generated biofilms on food contact surfaces (FCSs). The SLR included 13 peer-reviewed articles published between 2000 and 2020. Sanitizer concentration, type, contact time, surface type, and …

Exploring Non-Traditional Yeast For Flavor Innovation In Non-Alcoholic Beer, Andrew Maust, Rahul Sen, Scott Lafontaine

Food Science Faculty Publications and Presentations

The demand for nonalcoholic beer (NAB) is growing, with nontraditional yeast strains emerging as valuable tools for brewers to craft distinct NABs. However, independent information about the performance of these commercially available yeasts remains limited. In this study, 11 nontraditional yeast strains were evaluated at two wort nutrient levels to assess their impact on beer chemistry, sensory attributes, and volatile profiles. Basic fermentation metrics were monitored, followed by descriptive sensory analysis and GC-MS/MS quantification of volatile compounds. Results revealed significant differentiation among yeast strains with unique aroma and flavor profiles driven by variations in ester production, fusel alcohol synthesis, and …

Rice Tolerance To Fluridone At Different Application Timings And In Mixtures With Commonly Used Herbicides, Maria Carolina Souza, Jason K. Norsworthy, Thomas R. Butts, Robert Scott

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Introducing new herbicides requires a comprehensive understanding of how crops respond to various herbicide-related factors. Fluridone was registered for use in rice production in 2023, but research on rice tolerance to this herbicide is lacking. Hence, field research aimed to 1) evaluate the effect of fluridone application timing on rice tolerance and 2) assess rice response to fluridone in a mixture with standard rice herbicides applied to 3-leaf rice. Both experiments were conducted in a delay-flooded dry-seeded system using a randomized complete block design, with four replications. Treatments in the first experiment included a nontreated control and 10 application timings, …

Greenhouse Gas Emissions From Flood-Irrigated Rice As Affected By Phosphorus Fertilizer Source, Chandler M. Arel, Kristofor R. Brye, Diego Della Lunga, Trenton L. Roberts, Richard Adams

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Research into alternative phosphorus (P) fertilizer sources that may be able to supplement P resources is necessary. Struvite (MgNH4PO4 · 6H2O) can be made by removing excess nutrients from waste sources and may reduce greenhouse gas (GHG) emissions from cropping systems. This study sought to quantify GHG [i.e., methane (CH4), nitrous oxide (N2O), and carbon dioxide (CO2)] fluxes, season-long emissions, and net GHG emissions from chemically precipitated struvite (CPST) and synthetic and real-wastewater-derived electrochemically precipitated struvite (ECST) compared to monoammonium phosphate (MAP) and an unamended control (UC) from flood-irrigated rice (Oryza sativa) grown in P-deficient, silt loam soil in a …

Effect Of Heat Stress On Ileal Epithelial Barrier Integrity In Broilers Divergently Selected For High- And Low-Water Efficiency, Elizabeth S. Greene, Brooklee Roach, Maria Fernandez Cuadrado, Sara Orlowski, Sami Dridi

Poultry Science Faculty Publications and Presentations

Water scarcity and rising global temperatures are two of the greatest current and future threats to poultry sustainability. Therefore, selection for water efficiency (WE) and heat resilience are of vital importance. Additionally, intestinal integrity is of critical importance under challenging conditions to maintain nutrient absorption and therefore, growth and performance of broilers. Here, we examined the effect of chronic cyclic heat stress (HS) on the ileal expression profile of tight-junction, gap-junction, adherens, and desmosome genes in the fourth generation of divergently selected low (LWE)- and high water efficient (HWE)-chicken lines. LWE birds exhibited higher levels of gut permeability, regardless of …

Registration Of R19-42848 As A Drought-Tolerant, High-Yielding Soybean Germplasm Line, Chengjun Wu, Derrick Harrison, Liliana Florez-Palacios, Andrea Acuna, Daniel Rogers, Rafael Marmo, John Carlin, Ben Fallen, Leandro Mozzoni, Caio Cenella Vieira

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

R19-42848 (Reg. no. GP-532, PI 706865) is a high-yielding soybean [Glycine max (L.) Merr.] germplasm with drought tolerance released by the University of Arkansas System - Division of Agriculture Research & Extension Center in 2024. It is an F4-derived selection from the cross R12-2237 (drought-tolerant) x R12-519 (high-yielding). R19-42848 is a conventional (non-genetically modified) soybean with a relative maturity of 5.2. Plants have determinate growth habit with purple flower color, gray pubescence, and tan pod wall at maturity. Seed of R19-42848 has buff hilum color, 100-seed weight of 13.8 g, and contains on average 404.5 and 211.5 g kg-1 of …

Optimized Atmospheric Air Cold Plasma Seed Treatments Differentially Enhance Plant Growth And Herbivore Resistance In Soybean (Glycine Max) And Sorghum-Sudangrass (Sorghum X Drummondii), Deepak Dilip, Niitha Modupalli, Soumya Unnikrishnan, Mahfuzar Rahman, Rupesh Kariyat

Entomology and Plant Pathology Faculty Publications and Presentations

Atmospheric air cold plasma treatments (cold plasma; CP) have emerged as a promising technology in various fields, including medicine, agriculture, and environmental sciences. While CP treatment has been optimized in many fields, we lack empirical data on the efficiency and effectiveness of CP treatments in deterring insect herbivory, a recent development in CP application. Needless to say, by fine-tuning parameters such as plasma discharge method, exposure time, source gas, and input voltage, researchers can enhance the desired effects while minimizing any potential side effects. Reactive oxygen and nitrogen species (ROS and RNS) generated during CP treatments can potentially play a …

Arkansas Cotton Variety Tests 2024, F. Bourland, J. Gann, B. Lovelady, B. Guest Jr., J. Mcalee, L. Martin, Z. Treadway, C. Henderson

Arkansas Agricultural Experiment Station Research Series

The primary goal of the Arkansas Cotton Variety Tests is to provide unbiased data regarding the agronomic performance of cotton varieties and advanced breeding lines in the major cotton-growing areas of Arkansas. This information helps seed companies establish marketing strategies and assists producers in choosing varieties to plant. These annual evaluations will then facilitate the inclusion of new, improved genetic material in Arkansas cotton production. Adaptation of varieties is determined by evaluating the lines at five University of Arkansas System Division of Agriculture research sites (Manila, Keiser, Judd Hill, Marianna, and Rohwer). The 2024 tests at Keiser were adversely affected …

Drought And Herbivory Drive Physiological And Phytohormonal Changes In Soybean (Glycine Max Merril): Insights From A Meta-Analysis, Manish Gautam, Rupesh Kariyat

Entomology and Plant Pathology Faculty Publications and Presentations

With climate change, abiotic and biotic stresses such as drought and herbivory are predicted to further diminish agricultural productivity. Soybean (Glycine max [L.] Merrill), a crop of global economic importance, is vulnerable to both. However, the interactive effects of drought and herbivory on soybeans haven't been explored, especially through the lens of physiological and phytohormonal changes. To address this, we conducted a meta-analysis from 114 published studies, further reduced to 31 after removing redundancy, with data on physiological (photosynthesis and stomatal conductance) and phytohormonal traits (jasmonic acid [JA] and salicylic acid [SA]) of soybeans under drought, herbivory, and their combination. …

Pesticide Use In Integrated Pest And Pollinator Management Framework To Protect Pollinator Health, Ngoc B. Phan, David J. Biddinger, Edwin G. Rajotte, Guy Smagghe, Gadi V.P. Reddy, Zong-Xin Ren, Neelendra K. Joshi

Entomology and Plant Pathology Faculty Publications and Presentations

Agricultural pesticides have historically been a critical tool in controlling pests and diseases, preventing widespread suffering and crop losses that led to catastrophes such as the Great Irish Famine (1845–1852) and the Cotton Boll Weevil Infestation (1915–1916). However, their usage has brought challenges, including resistance development, secondary pest outbreaks, harm to non-target organisms like pollinators, and environmental contamination. In response to these concerns, integrated pest management (IPM) has emerged as a comprehensive approach, emphasizing non-chemical pest control methods such as cultural practices, biological control, and crop rotation, with pesticides as the last resort. IPM has evolved, influenced by regulations like …