Digital Commons Network^™

Encapsulation Of Probiotics By Cellulose Nanocrystal-Alginate Composite Beads For Ph Stimuli-Responsive Delivery, Akrip Jati

Graduate Theses and Dissertations

Microencapsulation has garnered significant interest, with oral probiotics delivery systems showing enormous potential to help restore the gut microbiome. This method holds vast potential to protect and release specific microbial strains to the desired target site (i.e., colon) within the gastrointestinal tract (GIT). However, current encapsulation methodologies, utilizing either synthetic or biological materials as carriers, encounter challenges such as suboptimal encapsulation efficiency, premature probiotic release, and inadequate control over release kinetics. In this work, hydrogel microsphere (HM) composites of different cellulose nanocrystal (CNC) forms (i.e., colloidal (c), and crosslinked (x)) and alginate (ALG) were used as advanced controlled release systems …

Employee Development And Employee Resilience In The Post-Covid-19 Workplace: A Quantitative Study Of High School Educators, Amy Keiser Maffei

Graduate Theses and Dissertations

The problem addressed by this research is the need for protective factors to support teacher resilience. Organizations that fail to develop employee resilience risk failing to enjoy the positive outcomes associated with it. Research-based methods to improve resilience may benefit organizations, including school districts. The purpose of this study was to examine the relationship between employee development provided by a school district and the resilience of its high school teachers in the post-Covid-19, in-person workplace. Conservation of Resources theory served as the framework to guide the research. Study participants completed a questionnaire with Likert-style response options, with items to assess …

Bactericidal Mechanism Of Peracetic Acid Against Salmonella Mediated By Reactive Oxygen Species, Mohammed Khalid Wheib Al-Doury

Graduate Theses and Dissertations

Peracetic acid (PAA) is extensively used as a bactericidal agent in poultry processing to reduce foodborne pathogens, including Salmonella enterica serotype Typhimurium (S. Typhimurium). Despite its widespread application, the exact mechanisms underlying its bactericidal effects, particularly the role of reactive oxygen species (ROS), remain incompletely understood. This dissertation examines the role of ROS in PAA-mediated bacterial killing and explores both genetic and metabolic factors that influence bacterial susceptibility to PAA. Findings from these studies have implications for enhancing the efficacy of PAA, thereby improving food safety practices in the industry.

The first study investigates ROS as a central component …

Synthesis Of Chemical Fuels And Feedstocks From Co2 For Extraterrestrial Applications, Samuel Keith Conlin

Graduate Theses and Dissertations

The reduction of CO₂ into products for either the storage of renewable electricity or to act as a source of renewable feedstock for industry, is not economically feasible given the current costs of renewable energy. Significant amounts of work have gone into attempting to optimize both electrochemical and nonthermal plasma-based CO₂ reduction systems in an attempt to reduce side reactions and improve energy efficiency in order to meet cost feasibility targets. These techniques can also be adapted for In-Situ Resource Utilization (ISRU) contexts, which are far less sensitive to the cost of renewable energy yet have more strenuous …

Emotional Intelligence And Self-Direction Orientation: An Examination Of Non-Academic Factors In Post-Pandemic Community College Students In Kansas And Missouri, Ashley Rader

Graduate Theses and Dissertations

Post-pandemic learners face academic and non-academic challenges due the educational disruption caused by the COVID-19 virus. ACT college admissions test scores dropped to a 30-year low in 2023, falling the most significantly and rapidly during and after the pandemic (ACT, 2023) and recovery from these childhood and adolescent learning deficits has not been seen to date (Betthäuser et al., 2023). Research on non-academic factors, not as widely studied as academic factors, is crucial to understand where these learners’ deficits further lie. Two of those factors – emotional intelligence and self-direction orientation – were the key concepts of interest in this …

Understanding Support For Former Foster Youth: Independent Living Coordinators Perspectives On Resiliency For Foster Youth In Higher Education, Aaron Abbott

Graduate Theses and Dissertations

This dissertation examines the resilience of former foster youth in higher education, focusing on the perspectives of Independent Living Coordinators (ILCs) in Arkansas. The study explores the support systems and challenges that foster youth encounter, assessing factors that contribute to or hinder their educational success. Using a qualitative methodology with semi-structured interviews, it identifies key protective factors such as emotional support, stable mentorship, and institutional programs that promote resilience among foster youth. The findings suggest that tailored interventions and a strengths-based approach can significantly improve outcomes for this vulnerable student population. This research contributes to existing literature by offering insights …

Exploring The Interplay Between Testosterone Levels And Gender Role Attitudes, Arial Bloshinsky

Graduate Theses and Dissertations

Traditional gender role attitudes align men with resource management and women with nurturing. The Challenge Hypothesis proposes that resource management is associated with higher testosterone levels, whereas nurturing is associated with lower testosterone levels. Therefore, traditional gender role attitudes may be associated with people’s testosterone levels. Furthermore, during the transition to parenthood, traditional gender role attitudes may become particularly salient, as shifting biological, social, and cultural roles during this transition make these attitudes an integral part of daily life. In this longitudinal study of expectant couples, participants completed a baseline survey and baseline session, during which they completed measures and …

Cognitive Bias, Memory, And Fearfulness Of Red Jungle Fowl And Athens Canadian Random Bred Chickens, Victor Juwon Oyeniran

Graduate Theses and Dissertations

Our understanding of how poultry perceive and interpret their environment is essential to enhancing their welfare; over the years, animal welfare science has relied on measures of the behavioral and physiological components of affective states (positive and negative) as welfare indicators. There is an increasing interest in the study of chicken’s affective states using the Judgment bias test (JBT) as a tool for assessing welfare through their responses to ambiguous cues. This study investigates the cognitive performance of two chicken breeds with different evolutionary histories: Red Junglefowl (RJF), the primary ancestor of modern chickens, and Athens Canadian Random Bred (ACRB), …

Enhancing Selection Intensity With High-Throughput Phenotyping Data In Plant Breeding, Ashmita Upadhyay

Graduate Theses and Dissertations

Genomic prediction (GP) has proven to be an essential tool to accelerate the cultivar development pipeline by predicting the performance of un-phenotyped lines in the field of plant breeding. However, the prediction accuracy is bounded by the heritability of the target trait, limiting the efficiency of the single-trait GP model. To overcome the limitation, a multi-trait genomic prediction model using high-throughput phenotyping (HTP) data can be used to leverage secondary traits to boost the predictive ability of the target trait. This study aimed to assess the efficiency of the multi-trait (MT)- GP model powered by HTP derived secondary traits in …

Locating Health Inequities: Understanding The Dynamic Role Of ‘Place’ In The Social Determinants Of Health And Healthcare Accessibility, Abbie Sudduth Page

Graduate Theses and Dissertations

Objective. The social determinants of health (SDH) are various non-medical factors that influence health behaviors and health outcomes, and they are measured in variety of different ways. The purpose of this dissertation is to explore the relationship SDH items that may group to form a new domain and may be associated with outcomes of health care accessibility. This dissertation seeks to explain a novel understanding of social determinants of health and healthcare accessibility through the lens of the socioecological model and place-based SDH items.
Methodology. This retrospective study design utilized data from the baseline survey and year-22 wave of the …

Diseases Of Cannabis Sativa And The Epidemiology And Molecular Diversity Of Neofusicoccum Parvum, Hannah V. Zima

Graduate Theses and Dissertations

Cannabis sativa has been an underutilized agricultural resource in the United States, largely due to federal regulations distinguishing marijuana from hemp. In 2018, Congress passed a Farm Bill, which defined hemp as C. sativa containing a tetrahydrocannabinol (THC) level of no more than 0.3%. As a result, commercial hemp production began in most states in 2019, including Arkansas, and was accompanied by numerous challenges like diseases and pests. The research on the epidemiology of diseases affecting C. sativa is limited, and understanding the pathogens is in its early stages in the U.S. For this study, an initial disease survey was …

Detection Of Fungicide Resistance In Population Of Corynespora Cassiicola From Arkansas Soybean And Cotton Fields, Rafael Zaia

Graduate Theses and Dissertations

Target spot, caused by the fungus Corynespora cassiicola, has reemerged since 2016 as an economically important disease on soybean and cotton across the Southern U.S. The quinone outside inhibitors (QoI) and succinate dehydrogenase inhibitors (SDHI) are important fungicide classes used to control foliar diseases in soybean and cotton. The efficacy of these products is rapidly decreasing, impacting control, and causing significant yield losses. The overall objective of this study was to determine the risks associated with chemical control by screening fungicide sensitivity, evaluating target site alterations, and analysis of disease control efficacy and yield response of fungicides for soybean in …

Interactive Effects Between Bluetongue Virus Infection And Insecticide Exposures In Culicoides Sonorensis, Parker Mullins

Graduate Theses and Dissertations

Culicoides biting midges are common pests around the world of humans, livestock, and wildlife. In addition to nuisance blood feeding, they are also able to transmit pathogens to their hosts like bluetongue virus (BTV) and African horse sickness virus, which can be damaging in terms of both production economics and animal welfare. In order to protect humans and livestock from biting pests like Culicoides, a wide array of interventions is recommended, but chemical insecticides and repellent use are ubiquitous. For a multitude of reasons ranging from natural weathering of applied insecticides to the increase in resistance-associated mutations and behaviors in …

Impact Of Equipment Type On Measured Particle Size Of Civil Engineering Materials, Tanner Turben

Graduate Theses and Dissertations

Particle size analysis (PSA) captures the size distribution of fine-grained or emulsified materials with particles generally smaller than 1000 microns. Asphalt emulsions and many other civil engineering materials do not leverage PSA for material specifications or acceptance despite the insight into material performance and quality gained through understanding the particle size. The objectives of this study are to compare PSA measurement principles by testing 13 civil engineering materials by laser diffraction, Coulter counter, and microscopy and to develop a draft standard procedure for asphalt emulsion PSA. Asphalt emulsions, cementitious materials, sands, clays, and biological samples were selected to represent a …

Fungal Pathogen Control And Microbial Ecology: Insights From Soybean Seed Production, Samantha Rigo Segalin

Graduate Theses and Dissertations

This study evaluated the effects of planting date (PD), seed vigor, and chemical seed treatments on the plant stand and yield of two soybean cultivars with different maturity groups (MGs) across four locations in Arkansas from 2018 to 2021. Early planting in early May (early PD) led to higher plant stands and yields compared to late planting in early June (late PD). The interaction between planting date and cultivar was significant, with both cultivars showing higher plant stands on early planting dates. Seed vigor and seed treatment also significantly impacted plant populations; high-vigor seeds planted early resulted in better stands …

Letters To Whiteness: Reflections On A White Artist-Educator Identity Through Dialectical Materialism, Richard Peterson

Graduate Theses and Dissertations

In this thesis, I reflect on my identity and experience as a white male and an artisteducator through a lens of critical whiteness and dialectical materialism. I utilize creative writing, and storytelling to speak more metaphorically about my own experiences and feelings in relation to whiteness to understand how I now operate as an artist-educator. Through dialectical materialism, I break down the social change described within the stories of growing up in the United States and intergenerational relationships with other white male figures, displaying more intricate ways I understand how similarities and differences change over time within the white identity …

White Guilt: An Ameliorative Proposal, William Moix

Graduate Theses and Dissertations

Common in the philosophy of race literature – notably those centered on critiques of whiteness and the oppressive structures therein – we find that guilt is looked upon rather divisively. On one hand, representative of what I call the “abolitionist” position, we find that such states serve no function but to stifle progress towards social justice. Feeling such emotions in relation to one's race seems to lead necessarily to a retreat from the social endeavor of racial justice, resulting in selfish requests for absolution. On the other hand, representative of what I call the “proponent” position, we find prescriptions to …

Breaking The Silence: Exploring The Impact Of Supervisor Vulnerability On Menstrual Disclosures At Work, Marilla Hayman

Graduate Theses and Dissertations

Management research has traditionally overlooked the significance of the human body in the workplace. However, recent recognition of organizational body work has prompted the examination of biological processes such as pregnancy and breastfeeding. Menstruation, however, has received little attention, despite the challenges faced by menstruating employees. The invisibility and silence around menstruation at work hinders managers' understanding of employee needs and prevents employees from accessing needed accommodations. An important first step in remedying this problem is understanding the factors influencing employees to disclose their menstrual symptoms and seek support. Bringing together theories of organizational body work and concealable stigmas, this …

Influence Of Invasive Species, Drought, And Stream Permanence On Stream Crayfish Species With A Focus On The Imperiled Mammoth Spring Crayfish (Faxonius Marchandi), Leah Marie Bayer

Graduate Theses and Dissertations

Freshwater crayfish constitute one of the most-threatened taxonomic groups in North America. Invasion by other crayfish species as well as habitat degradation through alteration of natural flow regime are two of the most prominent threats to crayfish persistence. Additionally, extreme weather events like droughts can amplify threats posed by other stressors on crayfish populations and are expected to increase in frequency, magnitude, and/or duration in the future, which may negatively influence narrow-ranged endemic crayfish populations typical of the Southeast. The Mammoth Spring Crayfish, Faxonius marchandi, is a narrow-ranged endemic that occurs in the Spring River drainage of Arkansas and Missouri …

Understanding The Emergence Of Self-Determination In Children With Disabilities Through Family Experiences In Early Childhood: A Qualitative Study, Karen K. Lange

Graduate Theses and Dissertations

Abstract A person’s ability to be self-determined begins to develop through the earliest interactions in life within the context of the family and caregiving environments. This qualitative phenomenological study of the experiences of eight parents representing seven families of young children explored how families promote their children’s early development of the skills, abilities, and attitudes of self-determination. The critical importance of the family context for the promotion of self-determination in young children is seen in the four themes that emerged from the experiences shared by these families. (1) The family context is transformed by a child with a disability, changing …

Investigation Of Optically Pumped Gesn Quantum Well Lasers, Grey Steven Abernathy

Graduate Theses and Dissertations

Silicon photonic integrated circuits enable the capability of producing on-chip processing of photonic signals, including both emission and detection. Emission materials, however, have been limited for monolithic integration due to high processing temperatures, indirect bandgap materials, and material integration complications. The (Si)GeSn material system has recently attracted attention due to the bandgap transition from the Si and Ge, naturally indirect bandgap, to direct bandgap with sufficient Sn incorporation. Additionally, the low growth temperature (CMOS compatible; <400 >°C) of (Si)GeSn materials can enable the monolithic integration of the highly desired mid-infrared light emission on the Si Photonic platform. This dissertation first discusses …

Synthesis Of Nanoparticles And Their Applications In Power Module Packaging And Organic Electronics, Xinsong Zhang

Graduate Theses and Dissertations

Nanoparticles can greatly change the properties of regular materials due to their special structures. In this research nanoparticles, such as silver nanowires, silver nanospheres and expanded graphite, are used in interconnection materials for power module packaging, and in conductive films for organic electronics. Silver nanowires synthesized by polyol synthesis, are used as fillers in micron silver paste. The electrical and mechanical properties of the sintered hybrid silver paste are investigated and compared with those of micron silver paste. The composites of silver nanospheres and expanded graphite are mixed with PEDOT:PSS solutions in 5 different weight ratio. The electrical and optical …

Investigating The Applications Of Peps To The Measurement Of The Stabilities Of Staphylococcal Nuclease (Stw) And Human Acidic Fibroblast Growth Factor (Hfgf1), Motolani Omolade Matthew

Graduate Theses and Dissertations

This dissertation presents a detailed investigation into the applications of Protein Equilibrium Population Snapshot H/D Exchange Electrospray Ionization Mass Spectrometry (PEPS-H/D exchange or PEPS) method. This method is based on protein equilibrium unfolding, and its fundamental capability is to capture a "snapshot" of the protein's state, allowing us to monitor the ratio of the unfolded to folded populations at different chemical denaturant concentrations. First, to increase the accuracy of PEPS data analysis for assessing protein stability, the traditional linear extrapolation method (LEM) was replaced. Instead of using LEM, which calculates free energy change based on the peak ratio of unfolded …

Parallel Degree Planning In The Pursuit Of Academic Success For Pre-Nursing Students In A Competitive Entry Baccalaureate Nursing Programs, Elizabeth L. Mckinley

Graduate Theses and Dissertations

This study sought to understand the student perceptions of parallel academic degree planning for the competitive entry undergraduate Nursing program at a case study university. Parallel degree planning is a relatively new term of alternative curricular planning. The qualitative study includes nine students and their experiences in planning for their intended major while simultaneously planning courses that meet another major or degree program, and understanding how parallel degree planning aided their retention and student satisfaction as well as their academic advisor interaction. The study was completed at a research university where the Nursing program has a very lower acceptance rate, …

Development Of A High-Throughput Screening Platform To Profile Gene Delivery And Transcriptional Control In Macrophages, Alexis Ivy

Graduate Theses and Dissertations

Macrophages are an important cell type in the body responsible for orchestrating the inflammatory response and return to homeostasis. Macrophages are often implicated in a multitude of disease pathologies including delayed wound healing, excessive fibrosis, autoimmune disease, and immunosuppression within the tumor microenvironment. Although macrophages have been targeted for therapeutic applications, success in utilizing them has remained elusive due to their relative ease of phenotype switching between inflammatory and anti-inflammatory. The challenge that remains is developing clinically relevant delivery vehicles that can target macrophages without causing a phenotypic switch counter-productive to the desired response. This is especially important when targeting …

Investigating The Detection And Transport Of Low Molecular Weight Species To Better Understand Their Impact On Disease Pathology And Treatment, Haley Michelle Duncan

Graduate Theses and Dissertations

Due to the drastic differences in the projects involved, this dissertation will be split into two sections: Alzheimer’s disease and chronic kidney disease. Each chapter will contain an introduction, materials and methods section, results and discussion, conclusions, and works cited section. The Alzheimer’s disease chapter will also have a supplemental figures section containing the polyacrylamide gels that were silver stained and quantified via ImageJ. The presence of elevated levels of amyloid beta oligomeric species in the brain has been related to the pathology of Alzheimer’s disease. As these oligomeric species are transient in nature, their kinetics pose a challenge to …

Neural Interactions In Bottom-Up Communication, Prashant Chama Raju

Graduate Theses and Dissertations

The visual system’s remarkable ability to process vast amounts of sensory information rapidly and accurately is fundamental to cognitive neuroscience. This study investigates a key aspect of this capability: the compartmentalization of information into feature-specific subspaces during bottom-up communication. My primary question was: does Canonical Correlation Analysis (CCA) reveal a subspace that encodes color and direction of moving dot stimuli? I found that the first canonical component (CC1) does an excellent job decoding the stimuli, despite being one-dimensional while the stimuli were drawn from a two-dimensional space (red-green and up-down plane). I demonstrate that motion features are processed within distinct …

Quantifying Physical Function: Moving Towards A New Definition And Better Assessment, Anthony Campitelli

Graduate Theses and Dissertations

Though poor physical function (PF) and disability are two of the most impactful problems facing older adults today, the field of kinesiology has not yet devised a method of measuring PF, thus limiting investigations with the potential to lead to improved PF interventions and assessments. This dissertation aimed to develop a single, continuous measure of PF using a latent variable modeling approach, and then use the generated scores to evaluate the role of lower body muscular power in PF assessment and to construct an improved PF assessment battery for predicting overall PF. Each aim of this dissertation was addressed through …

How Local Interactions Give Rise To Large-Scale Conformational Changes In Proteins: A Molecular Dynamics Study, Shadi A. Badiee

Graduate Theses and Dissertations

Proteins are dynamic entities that undergo conformational changes essential for their biological functions. These structural changes often correspond with chemical events such as lipid interactions or environmental changes like protonation or acidification. Understanding the complex relationship between these chemical perturbations and the resultant mechanical responses is crucial for elucidating protein mechanisms. This dissertation investigates the chemo-mechanical coupling in the conformational dynamics of the bacterial ABC transporter Sav1866 and the impact of protonation on the Influenza virus hemagglutinin HA0. Using molecular dynamics simulations, we explore the conformational landscapes of Sav1866 and HA0. Our study examines how varying lipid compositions affect the …

Struvite Effects On Greenhouse Gas Emissions From Flood- And Furrow-Irrigated Rice In The Greenhouse, Chandler Arel

Graduate Theses and Dissertations

Over time, as the influences of climate-change and declining, mineable, global phosphorus (P) reserves begin to impact agricultural production systems, alternative fertilizer sources and management practices, such as struvite (MgNH₄PO₄ · 6H₂O) and furrow-irrigation, will be necessary to accommodate nutrient and water demands. The precipitation and use of struvite as a fertilizer-P source could reduce environmental damages caused by nutrient-rich wastewater streams, supplement domestic P supply, and improve the sustainability of flood-, and furrow-irrigated rice production by reducing greenhouse gas emissions. The study of struvite from both chemical and electrochemical precipitation processes is well documented, …