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Aligning strategy with school finance: A K12 district's organizational decision-making process for ESSER allocation
No full textThe financial decisions that central office administrators make in public school districts have far reaching implications for the entire school system. This qualitative case study examined how leaders in a mid-to-large Texas public school district made financial decisions regarding Elementary and Secondary School Emergency Relief (ESSER) funds. Using a grounded theory approach with an organizational decision-making lens, the study explored the district’s decision-making process through perceived alignments between spending and district strategic improvement goals and how goals shaped allocation decisions. Findings revealed that alignment among leaders rather than alignment to goals alone most strongly influenced decision-making. Given the district’s decentralized structure, recommendations for stronger decision-making standardization and communication to promote goal achievement are provided. A two-step framework is proposed to guide future district allocation practice. This study contributes to understanding how organizational decision-making influences education finance and offers practical frameworks to strengthen district-level fiscal decision-making processes
When danger strikes: The conceptual linkage between threat and sexual openness in women
No full textPrevious literature has suggested that women’s mating psychology may adaptively shift during times of environmental harshness. However, there is limited quantitative evidence examining associations between gender, environmental harshness, and sexual openness. Therefore, the current research sought to examine (a) perceptions of men’s and women’s frequency of using sex as a tool, (b) associations between gender, levels of environmental harshness, anxiety, and sexual openness, and (c) associations between environmental hardship primes, gender, anxiety levels, and sexual openness. Results revealed that participants believed women used sex as a tool to garner resources more frequently than men. However, this perception was not necessarily supported by the data. The findings, while inconsistent, indicated that for women with low levels of anxiety, feelings of resource scarcity were associated with lower levels of sexual openness. Future research should examine other environmental factors (e.g., living in a dangerous environment) that may influence women’s mating strategies
Effect of HEPES on phase diagram & yield of protein crystallization from metastable liquid-liquid phase separation
No full textPreparative protein crystallization is regarded as an economically sustainable alternative to chromatography for protein purification in biotechnological downstream processing. However, protein crystallization remains a poorly understood process that is often slow and difficult to reproduce. A promising strategy to enhance crystallization efficiency involves exploiting the metastable liquid–liquid phase separation (LLPS) of protein solutions. In this dissertation, it is experimentally shown that a significant enhancement of lysozyme crystallization yield occurs when employing a combination of two additives under LLPS conditions. The first additive, NaCl (0.15 M), promotes protein–protein attractive interactions and induces LLPS upon cooling. The second additive, 4-(2-hydroxyethyl)-1-piperazineethanesulfonate (HEPES, 0.10 M, pH 7.4), accumulates in the metastable protein-rich phase and thermodynamically stabilizes lysozyme crystals. HEPES was demonstrated to cause opposite effects on solubility and LLPS boundaries in the protein phase diagram leading to broadening of metastability gap. A colloid model based on Bark-Henderson perturbation theory was then developed and applied to theoretically and quantitatively examine the salting-out effect of HEPES on lysozyme crystal solubility and the salting-in effect of this additive on LLPS boundary. For the crystalline phase, a model based on cell theory is applied to solubility data to determine that HEPES increases protein-protein attraction energy by 2.7%. The observed decrease in LLPS temperature due to HEPES, is explained by considering that this molecule also increases the anisotropic character of protein-protein interactions.
The employment of these two additives produces crystallization yields exceeding 90% under LLPS conditions at a lysozyme concentration of 5% (w/v) and a total ionic strength of approximately 0.2 M, within an operational time of about one hour. The obtained crystallization yield is more than threefold higher than that achieved in samples containing NaCl alone under identical pH and ionic strength conditions. Furthermore, by examining crystallization yield as a function of incubation time and temperature, both below and above the LLPS boundary, a marked increase in yield was observed when the crystallization temperature intersected the LLPS temperature. This behavior demonstrates that LLPS promotes protein crystallization. Overall, these findings propose a practical and efficient strategy to enhance protein crystallization for other proteins, with applications in protein purification
Income-driven differences between urban neighborhoods shape prey availability and bat foraging activity.
No full textIncome-driven differences across urban neighborhoods have the potential to impact habitat quality and influence both invertebrate and bat communities. In this study we assessed whether income-driven differences in Fort Worth, Texas, shape invertebrate prey availability and bat foraging activity. We found that total invertebrate abundance was greater in low-income neighborhoods, while invertebrate diversity was greater in high-income neighborhoods. Bat activity and foraging, however, potentially did not vary with income. These results indicate that income-driven landscape practices affect prey communities, but this, in turn, did not directly influence bat activity. Instead, factors such as habitat connectivity, roost availability, and other anthropogenic disturbances may affect bat abundance and distribution in urban areas. Therefore, further research is needed to determine what factors in urban areas influence bat activity
Enlightenment ideas and American process: Creating the southern boundary, 1796-1800
No full textThis dissertation uses Enlightenment ideas to investigate how Americans created boundaries in the late eighteenth century. The lens through which this examination occurs is the expedition to delimit the Southern Boundary between the United States and Spanish Florida between 1796-1800. This boundary represented the first boundary demarcated on the ground between a European power and the United States. Andrew Ellicott, the U.S. Boundary Commissioner, utilized a multi-phased process of enlightenment influenced activity to create this boundary. The four categories which exemplify the phases of American boundary creation are the use of diplomacy, expressions of sovereignty, investigations of Natural History, and the practice of and inquiries into Natural Philosophy. Taken together, these phases of activity encompassed an early method of American boundary making.
Enlightenment ideas represent beneficial models through which to examine eighteenth-century boundary creation. While diplomacy in Europe resulted in Pinckney’s Treaty, implementing the treaty on the ground required additional interpersonal “borderland diplomacy.” A second Enlightenment influenced idea which helps frame boundaries are expressions of sovereignty. Americans articulated sovereignty and claimed land in ways that Europeans would recognize, but Native Americans distrusted writing, an important aspect in American notions of sovereignty. Nevertheless, the indigenous peoples of the Gulf South still understood sovereignty, despite communicating it in different forms.
The last two segments of Enlightenment influenced activity are investigations in Natural History and the use of Natural Philosophy. Observing, writing, and publishing about Natural History enabled the American boundary commissioner to interrogate the world around him through narrative discussions of zoology, history, politics, geography, and botany. These writings helped to figuratively impose order over the areas he traversed and claimed for the United States. A closely related field to Natural History, the practice of and inquiries into Natural Philosophy, comprise the last phase of Enlightenment informed activity. The use of the astronomy, whether through discussion of astronomical observations, using celestial bodies to find longitude and latitude, and the process of surveying, combined to delimit the boundary in conceptual and tangible ways. Taken together, these Enlightenment influenced processes, evidenced an American way of creating boundaries
Describing How Scenario Topic, Situation Urgency and Complexity Level Impacts Simulation Observers’ Clinical Judgment: A Secondary Analysis
No full textNurses use clinical judgment (CJ) in nearly every nursing task to make safe patient care decisions (Dickison et al., 2019). CJ, a complex cognitive skill, involves thinking through patient care situations to notice salient cues, interpret meaning, respond appropriately, and reflect on clinical decisions (Klenke-Borgmann et al., 2020; Tanner, 2006). However, novice nurses demonstrate inadequate CJ (Kavanagh & Sharpnack, 2021). Consequently, newly graduated nurses have trouble applying theoretical knowledge, which negatively impacts their clinical judgment and leads to medication errors (Murray et al., 2020) as well as unsafe hospital conditions (Chaboyer et al., 2021; Jessee, 2021; Treacy & Caroline Stayt, 2019). Nurse educators must find ways to improve learners’ CJ to meet essential nursing education requirements (American Association of Colleges of Nursing, 2021)
Total Mercury Concentrations in Tricolored Bats (Pipistrellus subflavus) from East Central Texas
No full textMercury (Hg) is a trace element metal with toxic effects on wildlife, including bats. Texas is the largest producer of mercury pollution in the United States, yet only two other studies have measured mercury concentration in bats in the state. We measured total mercury (THg) concentrations in fur (n=57) in endangered Tricolored bats (Pipistrellus subflavus) collected from two culverts in Leon County in East Central Texas. Fur THg concentrations were compared between sex, culvert collection site, and to concentrations observed in previous studies. There was no significant difference in THg between sex or culvert. There was a difference in the mean THg concentration with Tricolored bats collected in this study compared to those collected from the Northeastern U.S, but not from previous studies in Texas. Additionally, the THg concentrations were compared with the 10 ug/g toxicity threshold levels commonly used to assess ris,k and 5.2% of Tricolored bats in this study exceeded the toxicity threshold. This suggests that THg may pose a risk to the health of bats in East Central Texas, and protective measures need to be implemented to protect this species
Role of medical students in a pediatric oncology precision medicine clinic
No full textPrecision Medicine (PM) is revolutionizing patient care by integrating biomedical data, lifestyle factors, and environmental influences to guide treatment plans, particularly in the field of oncology. With its growing utility, there is a pressing need to ensure that recent medical graduates are competent in this field. This study examines the impact that involvement in a Precision Medicine Clinic (PMC) has on medical students' education and career plans. Surveys were distributed to medical students who presented at PMC meetings with the goal of assessing comfort, confidence, and perceived benefit of involvement, along with qualitative feedback. Results indicated increased comfort and confidence in PM and in the interpretation of Next Generation Sequencing (NGS) following involvement in PMC and a positive influence on future career plans. Qualitative responses highlighted enhanced critical thinking skills and career exploration. These findings underscore the significance of integrating hands-on PM experiences into medical education to effectively prepare future healthcare professionals for the medical landscape in which they will be working. Limitations include potential biases from retrospective survey responses, revealing an opportunity for future prospective surveys. This study offers a valuable framework for institutions seeking to incorporate PM into medical education curricula
SYNTHESIS AND CHARACTERIZATION OF MICRO- AND NANOCRYSTALLINE IRON-DOPED ZINC OXIDE AS A PLATFORM FOR INVESTIGATION OF ANTIBACTERIAL MECHANISMS
No full textIron-doped zinc oxide (Fe:ZnO) is a multifunctional material with applications in luminescent devices, catalysis, spintronics, and gas sensors. Specifically, iron-doped zinc oxide (FeZnO) combines magnetic and chemical stability properties, making it suitable for technological and environmental applications. This study explores how synthesis parameters, specically pH and dopant concentration, influence the morphology and properties of FeZnO micro- and nanoparticles. Hydrothermal synthesis was employed to prepare Fe:ZnO with doping concentrations ranging between one and ten percent. Morphological and compositional analyses were performed using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). We also observed ZnO antibacterial action for some of the synthesized samples in Staphylococcus Aureus cultures. Future work will focus on improving dopant distribution, exploring antibacterial activity, and leveraging computational tools to refine material design for specific applications
Economic Sanctions and Export Margins
No full textAs global integration has increased over time, so too has the use of economic sanctions as a policy tool. Sanctions have the potential to affect trade flows regardless of other intended objectives. We use a gravity model framework and the updated Global Sanctions Data Base to characterize the heterogeneous response of exports to various types of sanctions. Specifically, we use disaggregated product†level trade flows for 247 countries over the period 1962–2019 and focus primarily on exporter and importer sanctions. We extend the literature by showing that, when looking separately at the extensive and intensive margins of trade, complete sanctions have the strongest impact on the extensive margin, while partial sanctions matter most for the intensive margin. We also explore whether the effects of sanctions are anticipated and/or persist over time, and we find some evidence of both effects. We further add to the existing literature by using quantile regression in a panel data context with fixed effects to allow for heterogeneity in the impact of sanctions on trade margins. We find that complete sanctions disproportionately reduce exports for countries with low initial export volume, while partial sanctions are more likely to reduce exports in countries with high initial export volume