UARK (University of Arkansas )
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A Town Divided: Leadership at Hoxie
No full textFive elected School Board members, a School Superintendent, and local leaders in rural Hoxie, Arkansas, were people of strong beliefs who in 1955 desegregated their school district. In this article, I argue that a combination of moral leadership and pocketbook concerns drove these men to oppose outside forces intervening in Hoxie, Arkansas, and that by doing so these men created a precedence of using the federal courts to uphold integration
The One Bright Spot Where All Else is Dark and Hopeless. Images of Class, Race and Culture in Britain\u27s Imperial Education System During the Nineteenth Century
No full textThis paper outlines the ideologies that underpin the language of education, and the relationship between this language and educational policy in Britain and abroad. These topics illustrate that the abstraction of ‘civilization,’ and the themes of ‘darkness’ and ‘light’ that surround it, are an essential part of how nineteenth century sociocultural relations should be studied
Using Interpersonal Motives to Identify Latent Profiles of Borderline Personality Pathology: Implications for an Overcontrolled Style of BPD
No full textBorderline personality disorder (BPD) is conceptualized as a disorder of undercontrol (i.e., behaviorally impulsive, emotionally expressive), with affective, interpersonal, and identity instability. BPD related impairment is high, yet diagnostic accuracy remains a problem for individuals who present with greater overcontrol (i.e., behavioral inhibition, expressive suppression), which occurs in some BPD subtypes. The current study used ecological momentary assessment (EMA) to expand on prior research by identifying latent profiles based on interpersonal motives for agency and relatedness, desire for predictability, perceived dependency, and self-efficacy in a sample of people with elevated BPD features (n = 136). Individual differences in overcontrol, undercontrol, and BPD features were used to identify patterns among latent classes of people, and to explore how trait overcontrol and undercontrol mapped onto momentary interpersonal styles. Multilevel modeling examined latent classes as moderators for the relationship between affective variability predicting emotion regulation. Five momentary interpersonal BPD profiles emerged, with one identified as overcontrolled, and none presenting as undercontrolled. Four latent classes of people emerged and individuals with the lowest overcontrol, undercontrol, and BPD features (GClass3) were most likely to exhibit an interpersonally overcontrolled profile (Profile 3). Compared to latent classes of people with higher levels of overcontrol, undercontrol, and BPD features, when feeling less positive than usual people in the lowest personality pathology group tended to use more intrapersonal emotion regulation, less interpersonal response seeking and responding, and more isolation. When feeling more negative than usual, they used more intrapersonal emotion regulation, more interpersonal response seeking and responding, and more isolation
The Black Bombers Of Ghana: Sport, Nation-Building And Pan-Africanism, 1958 To The 21st Century
No full textGhana’s Amateur Boxing Team, known as the Black Bombers, has impacted the country’s political and socio-economic development since its formation in 1958. This thesis argues that amateur boxing was one of the sports that Kwame Nkrumah, Ghana’s first president, used to promote nation-building and, more broadly, a Pan-African agenda. The team’s success in international competitions has widely projected Ghana\u27s sporting reputation and reinforced the Pan-African principles of Black pride and excellence in the global athletics arena, and beyond. This thesis traces the origins of amateur boxing and the formation of the Black Bombers, the squad’s participation in international athletics events in Africa and globally, and the sporting and other outcomes of such engagements. It also contends that the Black Bombers have helped to nurture world-class boxers, promoted nation-building and Pan-Africanism, and attracted local and foreign investment to assist in the socio-economic development of the country. This thesis also argues that young Ghanaian boxers looking to attain income, international moblity, and public recognition have considered joining the Black Bombers an economically appealing option
Hepatic Lipid Metabolism of High and Low Water-Efficient Broiler Lines Under Heat Stress
No full textHeat stress (HS) is one of the most critical environmental challenges negatively impacting global poultry production, significantly compromising broiler performance, welfare, and economic viability. Specifically, heat stress profoundly disrupts physiological and metabolic processes, including hepatic lipid metabolism. Two broiler lines were divergently selected for high (HWE) or low (LWE) water efficiency. Heat-stressed HWE birds showed reduced fat content compared to their LWE counterparts, and HS reduced abdominal fat content in both lines. The purpose of this study was to determine the difference in underlying molecular mechanisms involved in this divergent fat content between the lines. Day-old chicks were placed in 12 environmentally controlled chambers (2 pens/chamber, 20 birds/pen). On day 29, daily cyclic heat stress (36°C, 9h/day) was applied to half of the chambers, while the others remained at 25°C, in a 2x2 factorial design. On day 49, liver samples were collected for lipid metabolism-associated gene and protein expression analyses. Data were analyzed by Two-Way ANOVA and Tukey’s HSD test using Graph Pad Prism. Data are expressed as mean ± SEM and were considered significant at P≤0.05. HWE birds exhibited higher fatty acid synthase FASN protein levels under thermoneutral (TN) conditions (P=0.0011), with both lines showing decreased FASN protein levels under HS. Malic enzyme (ME) protein expression was also significantly higher in HWE compared to LWE birds under both TN and HS conditions. LWE birds showed higher ATP citrate lyase (ACLY) gene expression under HS. The findings of this study showed that the main transcription factors are also upregulated, suggesting whether there is other main lipogenic protein effectors or high hepatic lipolysis rate in HWE birds that merit further in-depth investigations
Heterogeneous Yield Effects of Cover Crop Adoption in U.S. Corn and Soybean Systems
No full textIdentifying the conditions where cover crops will succeed or fail is crucial for advancing conservation agriculture. Cover crops have been widely accepted as a conservation practice that can improve soil health and might improve or stabilize crop yields, though these benefits are not consistent across different regions. This study examines how heterogeneous factors can shape the effectiveness of cover crops on corn and soybean yields across the United States. Using the National Commodity Crop Productivity Index (Index) to measure soil productivity, this study examines how cover crop impacts vary across different levels of soil quality. A county level, 16- year panel dataset consisting of yields from the USDA-RMA, cover crop adoption rates from OpTIS, climate data from PRISM, and Index values from NRCS served as the basis for modeling. The models that were used in this study included fixed effects regressions, quantile regression, and Lewbel IV to identify any heterogeneous and non-linear effects of cover crop adoption on yields and soil productivity. The results show that for corn yields, in areas with low quality soil, the yields improve significantly, while diminishing in areas that had higher productivity to begin with. Conversely, soybeans had more consistent yield gain across the soil quality spectrum, though the area with the most beneficial gain was in the low Index regions. These finding carry significant policy implication, highlighting the need to account for heterogeneous factors when designing conservation policy
Advancing Point-of-Care Diagnosis of Joint Infection Using a Diffuse Reflectance Spectroscopy (DRS) System
No full textSeptic arthritis is a severe joint infection that can rapidly destroy cartilage and cause lifelong disability if not diagnosed and treated promptly. Faster, bedside diagnostic tools are needed to reduce delays and support timely treatment decisions while preserving standard laboratory workflows. A syringe-mounted diffuse reflectance spectroscopy (DRS) system was developed for rapid, sterile, point-of-care measurement of synovial fluid optical properties. Broadband light (400–650 nm) was delivered and collected through the syringe barrel without contaminating the sample. An empirical lookup table (LUT) and a boundary-aware Monte Carlo (MC) model were implemented to extract absorption (μₐ) and reduced scattering (μs′) coefficients from the measured spectra. Optical phantom studies confirmed that the system retrieves optical properties within 5–15% of known reference values and achieves signal-to-noise ratios exceeding 50 dB. Prospective patient samples (n = 19) demonstrated that scattering amplitude and reflectance band ratios (e.g., R₄₉₀/R₆₀₀) distinguish infected from non-infected fluid with ≥85% sensitivity and ≥90% specificity in under five minutes. The non-contact design preserves fluid sterility for culture confirmation. This work demonstrates a practical path from proof-of-concept to deployable point-of-care optical screening for septic arthritis, supporting faster treatment decisions and improved patient outcomes
High-Resolution Energy Efficient Selective Laser Sintering of Copper Nanoparticles
No full textCopper (Cu) is widely utilized in electronics and photonics applications due to its outstanding electrical and thermal conductivity. With increasing demand for miniaturization and higher precision in modern manufacturing, traditional selective laser sintering (SLS) techniques designed primarily for high-throughput production are becoming insufficient. These conventional methods struggle to deliver the resolution required for micro-scale fabrication and often cause thermal damage to sensitive substrates. Therefore, there is a growing necessity to develop compact and high-resolution laser sintering systems capable of precise microfabrication with minimal thermal influence. This study addresses this challenge by investigating nanosecond pulsed laser sintering as a method to achieve precise and energy-efficient fabrication of copper nanoparticles (Cu NPs) structures. Specifically, 70 nm Cu NPs were uniformly deposited onto aluminum foil substrates using a dry electrostatic powder coating method, avoiding solvent-related complications common in ink-based printing. A UV laser with a fixed wavelength of 355 nm was employed, and systematic experiments were conducted by exploring multiple key variables, including laser average power, repetition rate, scanning speed, focal spot location, and powder packaging density. Through careful optimization of these parameters, appropriate laser fluence conditions were identified, enabling effective sintering with minimal thermal damage and improved control over the morphology and quality of the fabricated microstructures. Experiments were conducted to selectively sinter Cu NPs into 2D microstructure. The sintered samples were thoroughly analyzed using scanning electron microscopy (SEM) to evaluate their microstructure and porosity. Results indicated that optimized parameter control enabled the formation of dense, smooth copper features with linewidths below 20 µm and minimal thermal impact on surrounding areas. Furthermore, short-wavelength UV laser processing showed significantly enhanced absorption by copper nanoparticles compared to conventional infrared lasers commonly used in commercial metal 3D printing, thereby improving overall energy efficiency. This work provides insights into the fundamental mechanisms underlying UV nanosecond laser-matter interactions during metallic nanoparticle sintering. By establishing optimized processing conditions, our findings support the advancement of precise and energy-efficient additive manufacturing techniques for copper and other metal nanopowders. The outcomes hold promises for broad applications, including flexible electronics, biomedical sensors, aerospace components, and microscale devices, ultimately contributing to innovation in precision manufacturing