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Synthesis and Properties study of Layered Magnetic Topological Materials
No full textThe discovery of topological materials (TMs) has opened up exciting opportunities for probing fundamental physics and enhancing innovative device integrations. These materials display various exotic properties, such as large magnetoresistance, high mobility, chiral anomaly, and surface Fermi arcs. The magnetic versions of ZrSiS family, LnSbTe and LnPS (Ln = lanthanide) have attracted intensive attention as these materials provide a new platform to study interplay between magnetism, topological states, and electron correlations. The vast pool of topological materials has provided exciting avenues to precisely engineer the topological states by modulating spin-orbital coupling, electronic dimensionality, and lattice constant through element substitutions. This research centers on previously less explored magnetic topological materials LnPS (GdPS, SmPS) along with their device fabrication techniques and systematic evolution of off stoichiometric PrSbxTe2-x. The compounds GdPS and SmPS exhibit orthorhombic crystal with distortion in P plane unlike square nets of Sb plane in tetragonal LnSbTe. GdPS displays antiferromagnetic ground state with insulator to metal transition (MIT) leading to gigantic isotropic negative magnetoresistance. With Se inclusion in GdPSxSe1-x, MIT suppresses resulting in more insulating behavior and a subtle degree of anisotropy emerges. Furthermore, the study of the evolution of PrSbxTe2-x reveals the correlation between the gigantic anisotropic negative magnetoresistance and magnetism in x = 0.3 composition
Synthesis and Characterization of Polymer-Coated Metal Nanostructures and Gelatin-Incorporated Hydrogels for Biomedical Use
No full textThe development of advanced materials for disease management and treatment presents a pressing challenge in the health sector. The overall objective of this research is to contribute to the development of advanced materials with tailored properties for biomedical applications, with a focus on cost-effective and robust nanoparticles and biomaterials. The first part of this work focuses on designing and synthesizing earth-abundant copper nanoparticles with desired optical properties. Copper nanoparticles, which provide a more affordable alternative to gold and silver, are being investigated due to their unique plasmonic properties. However, their susceptibility to oxidation limits their application. To address this challenge, copper nanoparticles are being surface-functionalized with polymers such as methoxy polyethylene glycol acetic acid (PEG-COOH) and polydopamine (PDA) to enhance their stability in different environments. Thorough investigations of the stability of PEG-COOH and PDA coated copper nanoparticles were carried out in aqueous solutions. Such a surface-modification method can be applied to other non-precious metals and metal oxides to improve their stability in various applications. In addition to nanoparticle research, the second part of this work aims to develop a gelatin-incorporated hydrogel for sustained protein delivery over 5-10 days for chronic wound healing. Building on our previous work with polyethylene glycol-based anionic injectable hydrogels, which showed improved release of human acidic fibroblast growth factor (hFGF) in vitro, gelatin is being incorporated to enhance the biodegradability and performance of the hydrogel. Gelatin, a natural polymer derived from collagen, possesses non-toxic, biocompatible, and bioadhesive properties, making it an ideal component for wound healing. Gelatin A or Gelatin B was incorporated into the formulations to improve the controlled release of hFGF and its mutants while maintaining the rheological properties of the hydrogel suited for wound healing applications
Exploring the Relationship between Grit, Burnout, and Academic Success among First-Year Osteopathic Medical Students during Fundamentals of Anatomic Science I Course
No full textBurnout is a significant issue among healthcare professionals. Burnout refers to the mental, emotional, and physical exhaustion that can develop throughout one’s career or studies. It can affect professionalism and patient care (National Academies of Sciences, Engineering, and Medicine: National Academy of Medicine, 2019). Studies have shown that burnout begins early in an individual\u27s medical education and can increase throughout their training (Voltmer et al., 2021). It has been suggested that students with a high level of Grit may exhibit some resistance to burnout (Jumat et al., 2020; Lee et al., 2022). This noncognitive trait measures a person’s ability to maintain passion and perseverance for long-term goals despite multiple setbacks and obstacles (Duckworth et al., 2007). Several studies have explored the relationship between Grit and burnout and academic success. Studies exploring the relationship between Grit and academic success (Olson et al., 2019; Alzerwi, 2020; Miller-Matero et al., 2018; Abd Elwahab et al., 2022; Welsh, 2020; Ursua et al., 2021; Fillmore, 2015) have shown mixed results, with some studies showing a positive relationship and others showing no relationship. However, the studies exploring the relationship between Grit and burnout (Cortez et al., 2019; Dam et al., 2019; Salles et al., 2014; Jumat et al., 2020; Lee et al., 2022) have shown a negative correlation between Grit and burnout. These inconsistencies in results for surrounding academic success, coupled with limited research on Grit specifically among osteopathic medical students, indicate a need for additional research. This study explored the relationship between Grit, burnout, and academic success in the Fundamentals of Anatomical Sciences I (FAS I) course in a southern osteopathic medical school. Two research questions guided the study: How is Grit associated with burnout in first-year osteopathic medical students after controlling for age, gender, ethnicity, and academic success in the FAS I course, and How is Grit associated with academic performance in osteopathic medical students after controlling for age, gender, ethnicity, emotional exhaustion, depersonalization, and academic efficacy? Results from this study showed no relationship between Grit and academic success in FAS I. Grit was found to be negatively correlated with the development of cynicism and positively correlated with academic efficacy. However, these had a weak effect and accounted for a small percentage of the model\u27s unique variation. This study reveals a relationship between Grit and the development of burnout, specifically cynicism and academic efficacy
Layer industry update: Nutrition associated with changes in production systems
No full textThis is not a hardcore research presentation but rather an overview of three North Carolina Layer Performance and Management Tests. I used the 39th, 40th, and 41st Layer Test Reports that cover the years 2013 through 2025. The proceedings cover white and brown egg strains as groups and the cage and cage-free production environments. Over all three of these tests the production environments were the same and met UEP Cage standards and the Humane Farm Animal Care cage-free standards. There are papers outlining the changes in more detail with all the statistics. This is an overview of visual trends in the production systems where the hens were managed in the same systems and nutritional programs
Pricing the unknown: An Analysis of Expected Value of Young Horses and Price-Determining Factors
No full textFrom a seller’s point of view in a market, it is crucial to plan the pricing strategies based on perceptions of buyer preferences and their willingness to purchase to ensure market success in selling and pricing. Applying this to the equine industry, this paper studies the factors determining the price of young horses (age ≤ 2 years) in digital auction platforms. Using data from Professional Horse Services, LLC (2012–2023), a Heckman’s two-step approach was employed, which involves a probit model as the first step and a hedonic price model as the second, aiming to correct for sample selection bias in the data. The first step evaluates the probability of sale of a young horse, and the results indicate that variables of breed category, veterinary information, and auction season significantly impact the sale probability of a horse. The second step evaluates the determinants of the final bid price of a horse based on observed sales, where the model’s key findings show that the final bid price is impacted by season of the auction, breed type, health and veterinary information, and discipline specialization. A comprehensive understanding of the findings reveals that various attributes influence the sale and final bid price of a young horse, providing buyers and sellers with better information to inform their bidding decisions and pricing strategies on digital auction platforms, respectively
Utilizing the Horseshoe Prior in Exploratory Factor Analysis and Gaussian Graphical Networks
No full textHigh-dimensional data analysis frequently involves extracting meaningful structure from noisy, sparse signals. In recent years, Bayesian shrinkage priors—particularly global-local shrinkage priors—have emerged as powerful tools for inducing sparsity while preserving signal fidelity. Among these, the Horseshoe prior has gained notable attention for its capacity to simultaneously shrink irrelevant parameters and retain substantial signals. This dissertation explores the Horseshoe prior as a unified framework for sparse Bayesian inference across theory, simulation, and real-world application. The first component develops new theoretical results establishing the asymptotic Bayes optimality of the Horseshoe prior in Gaussian graphical models (GGMs). We consider sparse precision matrix estimation where structure is inferred via shrinkage on off-diagonal entries. Under suitable sparsity and regularity conditions, we show that the posterior distribution concentrates around the true precision matrix at minimax-optimal rates. The second component investigates the performance of the Horseshoe prior in Bayesian Exploratory Factor Analysis (EFA), a method commonly used for dimension reduction and latent structure identification. Through a carefully designed simulation study, we evaluate the Horseshoe prior’s ability to recover sparse factor loading matrices under varying levels of noise, dimensionality, and factor sparsity. We compare its performance to other continuous shrinkage priors and assess model recovery using posterior summaries and uncertainty quantification. Our findings indicate that the Horseshoe prior offers a favorable balance between sparsity, interpretability, and estimation accuracy, even in challenging settings. The third and final component applies Horseshoe-based models to a real-world high-dimensional dataset. We consider an application in psychometrics where both interpretability and statistical regularization are crucial. We implement a Horseshoe prior within a suitable Bayesian model—either a sparse graphical model, a factor model, or a hybrid—and perform inference via Gibbs Sampler. The analysis highlights the practical advantages of the Horseshoe prior, including effective feature selection, robust parameter estimation, and clear interpretability of underlying latent structure. Taken together, this dissertation offers a comprehensive investigation into the theoretical properties, empirical behavior, and applied utility of the Horseshoe prior in sparse Bayesian inference. The results not only reinforce its theoretical foundations but also advocate for its practical relevance in diverse scientific domains. The work contributes to the broader goal of developing principled, scalable, and interpretable methods for high-dimensional Bayesian analysis
Assessment of Mental Health Needs for Chronically Unhoused Individuals Living in a Bridge Housing Community
No full textHigher rates of psychopathology and substance use are reported in individuals experiencing homelessness compared to the general population, especially in those who are chronically unhoused. Chronically homeless individuals are also less likely to access treatment for these problems because of barriers to care. Addressing housing needs is an important first step in engaging people who are homeless with the care they need. This project focused on assessing the mental health needs of a Housing First community in Northwest Arkansas, which has few barriers for entry but does not provide direct support for mental health. This project adopted a community-based participatory research (CBPR) approach, meaning the community this project is intended to serve was directly involved in the planning and completion of this research. Residents (n = 11) and staff (n = 5) from the community were interviewed with the goals of identifying mental health needs of its residents, articulating gaps between needs and current availability and utilization of services, and developing a list of recommendations for improving resident mental health. Recorded interviews were transcribed, and content analysis was used to identify common themes related to resident and staff perceptions of mental health goals of the program, mental health needs of residents, utilized services and their helpfulness, barriers to accessing care, and ideas for improving resident mental health. Based on these findings, seven recommendations for improving mental health were formulated and included: more on-site services, psychoeducation, out-of-the-box activities, rule enforcement, continuing to refer residents to off-site services, and providing additional support for staff through training and mental health support. Results were presented to interested residents (n = 7) and staff (n = 6) in feedback sessions. Participants expressed overall agreement with findings and recommendations and provided additional feedback. The possible application of these findings, strengths and limitations of this study, and future directions are discussed
The Influence of Retail Display Conditions on Ground Beef Quality and Palatability
No full textThe objectives of these studies were to evaluate the impact of retail display case type and muscle type on meat quality attributes, including color, lipid oxidation, texture, and volatile compound profiles, as well as to assess economic implications based on retail color degradation. Case type effects were further evaluated by considering environmental factors such as temperature, air velocity, and relative humidity and their influence on the shelf life of beef patties. An economic analysis was also conducted to estimate the value of patties based on a* (redness) scores at different points during retail display. In Study 1, differences in L* (lightness) values were observed among all case types on the initial day of display (P \u3c 0.01). By the end of display, the coffin and closed-door cases maintained the highest L* values compared to the traditional open front case, though they did not differ significantly from each other (P \u3c 0.42). The closed-door case had the greatest a* values at the end of display (P \u3c 0.02), and both the closed-door and coffin cases exhibited the greatest b* (yellowness) values, with no significant difference between them (P \u3c 0.26). Subjective lean color scores revealed that the coffin case had the lowest lean color scores and the highest discoloration scores (P \u3c 0.01). Lipid oxidation, measured by malondialdehyde concentrations, did not differ between case types or across display days (P \u3c 0.35; P \u3c 0.93). No differences were observed in shear force values across case types (P = 0.55), although patties displayed in the coffin and closed-door cases had numerically greater hardness (P \u3c 0.15), and greater springiness was observed in patties from the multideck and closed-door cases (P \u3c 0.06). Volatile compound analysis revealed higher concentrations of carbon disulfide and butyrolactone in cooked patties compared to raw samples (P \u3c 0.01). In Study 2, the closed-door case maintained higher L* values compared to the multideck case (P \u3c 0.01), and greater a* values were observed on day 3 of display (P \u3c 0.01). Among subprimals, the chuck exhibited the highest L*, a*, b*, and chroma values at the start of display (P \u3c 0.01), while hue values did not differ among subprimals (P \u3c 0.62). The TBARS values, indicative of lipid oxidation, increased daily in both cases (P \u3c 0.01), with no significant difference between case types (P \u3c 0.98). Tenderness analysis calculated from slice shear force showed that the chuck was less tender than both the round and sirloin (P \u3c 0.04), while no difference was detected between the latter two (P \u3c 0.58). Texture profile results varied primarily by subprimal, with fewer differences attributed to case type. The economic analysis did not identify a superior case type in terms of value retention or cost savings. Instead, meat value was more closely related to the initial a* color score at the beginning of display. Patties entering display at a color score of 4 or greater retained value for longer, resulting in fewer discounts and reduced product loss. Further research is warranted to better understand textural differences between subprimal types in ground beef, as well as their effects on palatability. Additional studies incorporating variations in case type, lighting, temperature, and packaging methods are recommended to optimize meat quality, extend color stability, and minimize retail loss due to discoloration
Farmers’ Perceptions About Drivers of Poverty: A Case Study of Cocoa Farmers in Ghana
No full textCocoa farmers in Ghana face numerous challenges that undermine their incomes and living standards, including high labor costs, fluctuating cocoa prices, high cost and limited access to inputs, lack of credit, illegal mining, weather risks, small farm sizes, outdated farming and drying technologies, and inadequate extension services. These issues reduce productivity, lower incomes, and perpetuate poverty. This study examined farmers’ perceptions about the importance of these challenges and assessed possible differences across regions and farm households’ socioeconomic status. In the summer of 2024, data were collected from 400 cocoa farmers in major cocoa-producing areas of Ghana’s Eastern and Ashanti regions. The Best-Worst Scaling (BWS) approach was used to rank the challenges and, thus, identify key poverty drivers. The analysis revealed that farmers perceive labor cost, low cocoa prices, high cost and limited access to inputs, lack of credit, and illegal mining as the top five drivers of poverty. Differences in the ranking of poverty drivers were observed across regions and farm sizes
The Connection Between Workplace Wellness Activities and Job Satisfaction in Manufacturing
No full textEmployers in all industries are concerned with creating and maintaining a workplace where their employees are engaged in their work. Job dissatisfaction is shown to lead to higher levels of turnover, absenteeism, and presenteeism. The purpose of this quantitative study will be to examine the connection between workplace wellness activity participation and job satisfaction, specifically for manufacturers in Southwest Missouri, Southeast Kansas, and Northeast Oklahoma. Manufacturers have experienced increased global competition in the last three decades, not just for their products or services but for quality talent. The value of this study is to show manufacturing employers that by providing workplace wellness activities to encourage healthier behaviors for their employee population, it could lead to higher job satisfaction (Richemond, 2016). By providing workplace wellness programs and activities that are aligned with the employee population to create healthier behaviors, employers have an opportunity to attract and retain employees (Diestel et al., 2014). Higher job satisfaction may lead to higher productivity and profitability as well as a reduction in turnover, absenteeism, and presenteeism