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Working Alongside People with Disabilities: Their Impact and Value
Get PDFU.S. policies such as the Workforce Innovation and Opportunity Act of 2014 and the Americans with Disabilities Act support the inclusion of adults with disabilities in all areas of employment. Through WIOA, the federal government required public entities to provide training and help job seekers with disabilities access high-quality, competitive, integrated employment in the labor market. Nevertheless, two-thirds of unemployed PWDs report wanting employment but cannot find a job. Negative perceptions held by employers and hiring managers and their views that PWDs lack abilities create barriers to employment. In contrast, research has also shown that coworkers can greatly influence successful workplace integration. This suggests the importance of understanding coworkers’ perceptions to allow them to accept PWDs as coworkers. This qualitative study aims to explore coworkers\u27 perceptions of working alongside People with Disabilities in a large hospital located in a large metropolitan area
Proton-Coupled Electron Transfer to Drive Biomass Conversion
No full textMeeting rising demands for commodity chemicals while simultaneously easing reliance on fossil fuels presents one of the most substantial challenges for chemistry to date. Biomass has emerged as a sustainable precursor to commodity chemicals but requires substantial deoxygenation to displace petrochemicals. Development of efficient catalysts to achieve these transformations remains one of the central goals of inorganic and organometallic chemistry. Electrochemical strategies to propel biomass conversion are attractive, providing the driving force for reactivity and insights into catalyst mechanism. This work focuses on proton-coupled electron transfer (PCET) to facilitate redox catalysis in biomass up conversion and homolytic bond cleavage in small organic molecules. For the first time, the deoxydehydration of vicinal diols to alkenes has been achieved without the use of sacrificial reductants. Reactivity is enabled by the electrochemical reduction of a Mo dioxo complex via PCET. Electrochemical PCET is also used to characterize the redox reactivity of a V dioxo complex. Understanding these redox properties uncovered the ability of the V dioxo complex to activate weak C-H bonds. Encouraged by the potent oxidizing power of metal oxo bonds, the electrochemical oxidative depolymerization of lignin to access valuable aromatics was targeted. The oxidation of lignin models was studied utilizing PCET to generate highly oxidizing Ru oxo complexes. Seeking to understand possible C-H activation pathways that enabled depolymerization of lignin generated interest in organic bond activation and functionalization. To achieve these oxidations electrochemically, a series of Ru complexes with distal basic sites were employed and their multisite PCET behavior was studied using electrochemical methods
Molecular Beam Epitaxy of GeSn on III-V Substrates for Photonic Applications
Get PDFThis dissertation explores the advancement of germanium-tin (GeSn) as a tuneable narrow bandgap material, crucial for the development of high-efficiency photodetectors and laser devices in near- and mid-infrared technologies. We investigate the synthesis challenges, particularly the lattice mismatch between GeSn alloys and substrates, which significantly affects their crystalline and optical qualities. Through molecular beam epitaxy, we examine the growth of Ge and GeSn on GaAs (001) substrates, employing Ge/GaAs and Ge/AlAs buffer layers to investigate these challenges. Our findings, characterized by X-ray diffraction, atomic force microscopy, reflection high-energy electron diffraction, and photoluminescence, demonstrate the production of high-quality Ge layers, achieving atomic steps and photoluminescence comparable to bulk Ge at growth temperatures between 500–600 °C. Subsequently, we grew GeSn films using a Sn compositional exponentially changing gradients and a substrate gradient approach to achieve films with 8 to 10 % Sn composition. Additionally, we introduce a novel algorithmic approach to control the Sn cell temperature logarithmically, allowing us to target and achieve linearly graded Ge1-xSnx compositions. One of such linear Ge1-xSnx gradient growths achieved a pseudomorphic graded composition up to 10 % before a partial relaxation gradient up to 16 %. The combination of experimental and algorithm-driven methodologies not only advances the understanding of GeSn film growth but also marks a major step forward in the synthesis of high-composition, and high-quality GeSn films. This work signifies the first demonstration of algorithmically driven, linearly graded GeSn films in the world, showcasing an advancement in the field of semiconductor technology
Quantifying Physical Function: Moving Towards A New Definition And Better Assessment
Get PDFThough 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 an independent research study, and each study recruited a sample of adults over the age of 50. The first study utilized Bayesian exploratory factor analysis (EFA) to construct a measurement model for PF which was determined to have a single-factor structure with all examined activity of daily living (ADL) movement task indicators loading on the PF latent factor (n = 41, p(θ|X) = 99.96%). A confirmatory factor analysis (CFA) model using the extracted factor structure implied by the EFA had excellent data-model fit (n = 42, PPP = .124, BRMSEA \u3c .001, BCFI = .952, BTLI = 1.190) and performed well in all posterior model diagnostics. Taken together, the EFA and CFA results indicate that PF can be indirectly approximated via factor analysis using measurements of the ADL movement tasks affected by PF. Factor scores were extracted for all participants and this score was termed the Physical Function Quotient (PFQ). Study two assessed the ability of lower-body muscular power to predict the PFQ scores extracted in study one and the Physical Performance Test (PPT-7) score. Generally, muscular power was a very poor predictor of both scores (n = 42, R2 ≤ .042, p ≥ .327). The final study, used exploratory regression to assess which commonly used PF assessments, taken together, creates the best predictive model for PFQ and PPT-7 in an effort to produce an optimized PF testing battery. Nine biomotor assessments and four ADL movement assessments were chosen for inclusion based on their validated and common use in PF research. Models including biomotor assessment predictors were generally poor predictors of PFQ, explaining less that 30% of the variance (R2 ≤ .294, p \u3c .001), but 8-foot up-and-go (8UG) on its own explained almost 100% of the variance in PFQ (R2 \u3e .999, p \u3c .001). On the other hand, neither biomotor nor ADL movement assessment performance generated models that predicted PPT-7 well (R2 ≤ .364, p \u3c .001). Cumulatively, these results demonstrate the utility of measuring PF indirectly with a latent variable modeling approach, biomotor assessments are not good real-time assessments of overall PF in healthy adults over 50 years of age, and 8UG is indicated for use as a simple assessment to approximate total PF
Motives for and Consequences of Deception in Romantic Relationships
Get PDFThe goals of this study are twofold. First, I examined the influence of sex, relational intimacy, and face concerns on deploying deceptive communication within romantic relationships. Second, I investigated the impact of deceptive communication on relational commitment and relationship satisfaction. Two hundred twenty-two college-aged students completed self-report measures assessing the variables of interest. Results demonstrated that men and women deceive their romantic relationship partners at similar rates; however, deception is differentially motivated across the sexes. In addition, results indicated that relational intimacy was negatively associated with the frequency of deceit, although relational intimacy was not significantly associated with specific motives for deception. While self-face concerns were positively associated with the frequency of deceit, other-face concerns were not significantly associated with the frequency of deceit. Finally, the frequency of deploying deceptive strategies was negatively associated with both relational commitment and relationship satisfaction
Communication Protocols against Attack Vectors
Get PDFCommunication Protocols against Attack Vectors
Presented at UA Power Group Undergraduate and REU Summer Research Poster Session on July 18, 2024.https://scholarworks.uark.edu/elegreu/1006/thumbnail.jp
Blend Feeding Broilers to Daily Nutrient Requirements
Get PDFBroiler producers and nutritionists have used phase feeding as a practical means to define broiler feeding programs. Each feed phase has discreet nutrient definitions intended to be fed for a defined number of days based on a feed mass delivered per broiler. A typical broiler feeding program would consist of three to five feed phases over the production cycle that intend to address the changing nutrient requirements as broilers age. Phase feeding programs are easily defined, practical to manage, and provide a predictable cost structure for broiler producers. Despite the practicality of phase feeding, there are inherent flaws that will be discussed and alternatives will be investigated
Associations Between Parenting Stress and Quality Time in Families of Youth with Autism Spectrum Disorder
Get PDFIncreased stress among parents of youth with ASD has been well-documented. However, research on aspects of the parent-child relationship and subsequent links to parenting stress is limited. We assessed parents (N = 511) of youth with ASD to examine relations between parenting stress and parent-child quality time (amount of quality time, shared enjoyment, synchronicity). Elevated parenting stress was associated with less time spent engaging with youth in shared activities and decreased parent and child enjoyment during shared interactions. Parents with elevated stress reported engaging in shared activities and experiencing synchronicity with their child less often than parents below the clinical threshold. Future research should emphasize longitudinal efforts examining the directionality of this relationship to better inform family-focused intervention
Understanding the Impact of Food Insecurity Among First-Generation College Students on the University of Arkansas Campus
Get PDFThe purpose of this study was to: 1) better understand food insecurity among first-generation college students and how it might differ from that of other college students, and 2) gather opinions from students that may serve as solutions to alleviate food insecurity. This study was conducted with a mixed-methods survey that included both open-ended and closed-ended questions. This survey had 670 responses. Nearly 10% of respondents stated that they were experiencing food insecurity. Almost 18% stated they were first-generation college students. A greater percentage of African American (P = 0.0022) and Hispanic Latino (P \u3c 0.0001) students were first-generation compared to all other students, while a lower percentage (P \u3c 0.0001) of Caucasian students were first-generation compared to other students. The results suggested that first-generation students were more likely to experience nine food insecurity impacts than non first-generation students. Further, both first-generation and non first-generation students indicated low levels of knowledge and/or use of existing resources on the University of Arkansas campus that can help address food insecurity needs. Finally, both first-generation and non first-generation respondents overwhelmingly favored food insecurity solutions centered around expanding access to campus food programs through lower costs and increased awareness of existing campus resources via improved advertising
