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2D ZEOLITE-BASED CATALYSTS FOR THE PRODUCTION OF BIOFUELS AND BIOCHEMICALS
No full textThe growing need for sustainable alternatives to fossil fuels has intensified interest in the catalytic conversion of lignocellulosic biomass, particularly lignin, into liquid transportation fuels. This research explores the development and application of bifunctional nickel-supported 2D ZSM-5 zeolite catalysts for the hydrodeoxygenation (HDO) and 2D ZSM-5 for hydropyrolysis of lignin A range of zeolite morphologies—including conventional and flower-like nanosheets—were synthesized with varying Si/Al ratios to tailor acidity and metal–acid synergy. Nickel was introduced via wet impregnation at loadings of 3–10 wt%, and catalysts were extensively characterized using SEM and EDS techniques. In addition, hydropyrolysis and HDO experiments were conducted under controlled hydrogen pressure and temperature conditions. Results demonstrated that increasing nickel loading significantly enhanced oxygen removal and shifted product selectivity toward lighter hydrocarbons. Catalysts with lower Si/Al ratios exhibited higher deoxygenation efficiency and favored the production of C6–C8 fuel-range hydrocarbons. 2D ZSM-5 zeolites improved cycloalkane yields and oxygen removal due to greater molecular accessibility. Product distribution analyses showed a clear transition from phenolic intermediates to aromatic and polycyclic hydrocarbons with increasing catalyst-to-lignin ratio for hydropyrolysis
Electrostatic Effects on the Transport and Dispersion of Micro-Nano Pharmaceutical Powders
No full textA predetermined amount of micro-nano powder particles contributes to the treatment during a patient’s inhalation of the bolus of respiratory micro-nano pharmaceutical powders in an aerosolized state from commercially available inhalers. The most popular inhalers are the metered dose inhalers (MDIs) and dry powder inhalers (DPIs). While inhaling, the complicated inlet velocity profile and turbulent flow in the mouth-throat significantly impact the gaining of electrostatic charge through triboelectric charging. The inhaled particles are not only varying sizes but also polarities of charges. However, few studies have been conducted to investigate electrostatic charge force effects on particle losses in the oral, pharyngeal, and laryngeal (OPL) regions before inhaling into the trachea and subsequent deeper lung. This research, however, has shed light on the integrated impact of powder particles’ size and electrostatic charge on the deposition of inhaled pharmaceutical particles in a polyester resin cast of a cadaver-based mouth-throat, a replicate of human OPL regions. Each powder aerosol particle was characterized for its aerodynamic diameter (size) and charge by an electronic single-particle aerodynamic relaxation time analyzer before and after passing through the mouth-throat cast. The study findings show that particles’ charge-to-mass ratio and electrical mobility varied with size. Electrostatic properties played a significant and enlightening role in particle losses in the mouth-throat cast. Deposition fraction or losses of powder particles were comparatively higher for DPIs than for MDIs
TESTING TOCQUEVILLE’S TROOPS: AMERICAN DEMOCRACY AT WAR IN MEXICO
No full textThis thesis explores Alexis de Tocqueville\u27s theory of democratic armies through the lens of the Mexican-American War (1846-1848), testing his predictions about how democratic social conditions influence military institutions and performance. Tocqueville argued that armies in democratic societies would face tensions between egalitarian ideals and military discipline, with citizen-soldiers resisting hierarchy while professional officers, often isolated from civil society, grew dangerously ambitious for war. He predicted that democratic armies would show energetic initiative but struggle with weak formal discipline, and that equality would fundamentally change the relationship between the military and the broader society. The Mexican-American War serves as an ideal case study, occurring just a decade after Democracy in America and representing the U.S.\u27s first major conflict since Tocqueville\u27s insights. Using soldiers\u27 letters, diaries, and memoirs, this study examines both the volunteer forces, which most closely embodied the citizen-soldier ideal, and the developing professional regular army. The findings reveal a complex reality. Predictably, according to Tocqueville, volunteers showed patriotic enthusiasm and also faced serious disciplinary issues and committed atrocities against civilians. However, regular army officers formed an unexpected professional identity rooted not in aristocratic separation but in humble, self-reflective, politically neutral service to democratic institutions. The thesis argues that while Tocqueville correctly identified key tensions in democratic military culture, he underestimated the disruptive effects of partisan politics and the capacity of democracy to foster new forms of military professionalism. The Mexican-American War sparked the rise of a uniquely American military ethos that blends professional expertise with democratic responsibility. This research enhances understanding of civil-military relations by showing how social conditions shape military institutions and highlights democracy\u27s capacity to adapt and create innovative solutions to its inherent contradictions
IMPROVING THE EFFECTIVENESS OF THE TEACHER PROFESSIONAL LEARNING COMMUNITIES IN SECONDARY EDUCATION
No full textThis Improvement Science Dissertation in Practice investigated how to enhance the relevance, effectiveness, and teacher ownership of grade-level Professional Learning Communities (PLCs) at a university-affiliated charter school in East Texas. Despite the district’s strong STEM and Project-Based Learning (PBL) emphasis, 60% of high school teachers reported that PLCs felt irrelevant, administratively driven, or misaligned with their daily instructional needs. Using Improvement Science methodologies, including Plan-Do-Study-Act (PDSA) cycles, root-cause analysis, a driver diagram, and embedded collaborative structures, this study implemented targeted interventions aimed at shifting teacher perceptions and strengthening PLC practices. Interventions centered on aligning PLC agendas with PBL, implementing structured peer-feedback routines such as the Critical Friends Protocol, and supporting PLC facilitators through explicit training. Data from teacher surveys, PLC artifacts, and qualitative reflections indicated that teachers valued increased collaboration, more purposeful agenda alignment, and opportunities for authentic instructional dialogue. Through iterative cycles, teachers demonstrated increased engagement, ownership, and relevance of PLC work, contributing to improved instructional alignment and collaborative culture. Recommendations for further research include expanding implementation across campuses, examining leadership transitions, and exploring additional PLC structures such as vertical and cross-campus PLCs
Enhancing Microgrid Protection Through Adaptive Decentralized Relay Coordination: A Solution to Blinding and Sympathetic Tripping
No full textIntegrating Distributed Energy Resources into microgrids modifies the network’s system parameters and causes it to exhibit behaviour, particularly during fault conditions. This is due to the greater variations in current direction and magnitude. When a microgrid runs in autonomous mode, Distributed Generators result in a reduced short circuit current compared to a system working in grid-connected mode. Microgrid protection issues, namely, blinding of protection, sympathetic tripping, and bidirectional power flow, occur in the power network under such circumstances. The impact of microgrid protection issues and changes in fault current leads to variations of overcurrent relay settings, their operating time and relay pair coordination. This paper presents an adaptive decentralized protection technique for ensuring the coordination of overcurrent relays in a microgrid network, even under situations of uncertainty. This method involves estimating the relay settings in the microgrid without considering DG and establishing relay coordination. The fault currents of the system, including DG, are calculated using the Thevenin equivalent circuit. These currents are derived from the perspective of the relay by analyzing the current and voltage measured at relay position before system fault. The proposed adaptive decentralized protection is developed and implemented in an IEEE-modified 9-bus and 14-bus system. The proposed method of coordination is compared against the conventional relay coordination method. The simulation studies are carried out in the MATLAB simulation and Digsilent Powerfactory 2023 version. The simulation results demonstrate effectiveness of proposed decentralized adaptive protection strategy in addressing all protection issues in the DG-integrated microgrid network
Pandemic-driven healthcare disruptions and their disproportionate impact on patients with diabetes: evidence from Texas
No full textBackground: Diabetic Ketoacidosis (DKA) is a life-threatening complication of uncontrolled diabetes. The COVID-19 pandemic may have increased DKA incidences and worsened outcomes both through the potential diabetogenic effects of SARS-CoV-2 infection (direct effect) and through pandemic-related disruptions in healthcare (indirect effects,) including delays in seeking or receiving care, reduced access to routine outpatient services, and strains on hospital capacity. The objective of this study is to examine changes in the frequency and outcomes of hospitalizations with DKA in Texas hospitals following the COVID-19 pandemic and to quantify the contributions of pandemic-related healthcare disruptions and SARS-CoV-2 infection. Comparisons to patients with Acute Myocardial Infarction (AMI) and Acute Kidney Injury (AKI) were made to assess the disproportionate impacts of healthcare system disruptions on DKA patients.
Methods: This retrospective observational study uses regression analyses to evaluate the relative contributions of healthcare disruptions and viral infection on DKA frequency, in-hospital mortality, and length of stay. Event study and difference-in-differences models are employed to analyze whether DKA cases were disproportionately affected compared to patients with AMI or AKI. Quarterly inpatient discharge records from 2018 to 2021 are obtained from the Texas Department of State Health Services. Over 8 million discharge records are examined.
Results: DKA hospitalizations increased by 8% post-pandemic, with half of the increase attributable to pandemic-induced healthcare disruptions (indirect effects.) The average mortality of patients with DKA increased by 44% compared to the pre-pandemic average. Non-COVID channels contributed to a 30% increase in mortality. Compared to AMI and AKI patients, DKA patients were disproportionately affected by pandemic-induced disruptions.
Discussion: The COVID-19 pandemic significantly impacted DKA outcomes through the direct effects of SARS-CoV-2 infection and through various healthcare system disruptions—such as reduced access to routine diabetes care, delays in seeking treatment, and hospital resource constraints. Policies supporting uninterrupted diabetes management, such as telemedicine and medication access programs may reduce adverse outcomes in future health crises
Population Health and Systems Science: Medical Student Feedback on a Novel Approach That Follows a National Curricular Framework
No full textIntroduction: Population Health and System Science, a longitudinal course at a new medical school in northeast Texas, incorporates case-based learning and experiential field visits during an 18-month pre-clerkship phase. The course integrates content from public and population health, preventive medicine disciplines, and health administration and leadership. Materials and Methods: A cross-sectional survey assessed student self-reports on achievement of session objectives and introduction to national core curricular, cross-cutting, and systems thinking domains. Results: Of 36 students, 33 responded. Most rated objectives favorably. Open-ended responses highlighted relevance to future practice and requested more content on biostatistics, epidemiology, health equity, and healthcare economics, financing, and policy. Discussion: Findings suggest the course effectively introduces key concepts, with opportunities to enhance foundational content in measurement, policy, and financial aspects of healthcare. Future studies should investigate application during required clinical rotations
EXPLORING VETERAN AND NON-VETERAN NURSING STUDENT SATISFACTION UTILIZING MARGINALITY AND FINANCIAL STRESS
Full text linkIt is widely recognized that there is a nursing shortage in the U.S. due to a growing aging population, nurses retiring, and a low nursing school capacity. Nursing schools can ameliorate part of this shortage by devising ways to increase nursing student success and graduation rates. This three-manuscript paper aims to present various ideas to help nursing schools in this endeavor. A relatively unstudied population is the veteran nursing student (VNS), the focus of this paper. The first chapter, Chapter 2: A Concept Analysis of Overload: Implications for Undergraduate Nursing Students Success, discusses the concept of overload so the reader can gain an in-depth understanding of overload as a precursor for potential failure in nursing students. The second chapter, Chapter 3: Marginality and Other Barriers to Progression in Undergraduate Veteran Nursing Students: A Scoping Review, is a scoping review exploring research articles that targeted specifically VNS and gives a glimpse into the barriers that VNS experience during nursing school. The third chapter is an original research study, Chapter 4: Exploring Veteran and Non-Veteran Nursing Student Satisfaction Utilizing Marginality and Financial Stress. This study explored financial stress, marginality, and satisfaction with life in 261 veteran and non-veteran nursing students (NVNS) utilizing a Qualtrics survey with demographic questions, the Financial Stress Scale College Version, Englund Marginality Index, and Satisfaction with Life Scale. Analysis was conducted in SPSS utilizing multiple linear regression and Mann-Whitney U tests, and demographic comparisons were conducted to discover differences and similarities between VNS and NVNS
EMERGENCY NURSES’ PERCEPTIONS OF A TRAUMA-INFORMED ORGANIZATIONAL CLIMATE: A CROSS-SECTIONAL STUDY
Full text linkHealthcare leaders face numerous challenges in today’s complex healthcare environment. The most pressing issues are staffing shortages and burnout among healthcare workers. By 2025, the U.S. healthcare system could experience a shortfall of up to 450,000 nurses, or 20% fewer nurses than needed to provide adequate patient care. High job dissatisfaction and burnout levels are significant factors driving many nurses away from the profession. This three-paper dissertation portfolio addressed how trauma-informed approaches and practices can enhance the work environment by establishing trauma-informed organizational climates to mitigate burnout. Understanding the impact of trauma-informed practices within healthcare systems supports the nursing workforce. This dissertation is composed of five chapters. The first chapter provides an overview of the dissertation research and explains the importance of a trauma-informed organizational climate for healthcare systems. The second chapter presents a concept analysis of trauma-informed professional development, which involves integrating trauma-informed practices into healthcare education. The third chapter consists of a scoping review of the impact of trauma-informed approaches on the healthcare workforce. The fourth chapter contains a report of original research that addressed emergency nurses’ perceptions of a trauma-informed organizational climate and the relationship of nurses’ perceptions of a trauma-informed organizational climate with role stress and burnout. The fifth and final chapter provides an overview and synthesis of the portfolio which concludes with suggestions for employing trauma informed principles to positively influence the future of nursing
A mechanistic understanding of the effect of Staphylococcus aureus VraS histidine kinase single-point mutation on antibiotic resistance
Full text linkBacterial genomic mutations in Staphylococcus aureus have been detected in isolated resistant clinical strains, yet their mechanistic effect on the development of antimicrobial resistance remains unclear. Resistance-associated regulatory systems acquire adaptive mutations under stress conditions that may lead to a gain-of-function effect and contribute to the resistance phenotype. Here, we investigate the effect of a single-point mutation (T331I) in VraS histidine kinase, part of the VraSR two-component system in S. aureus. VraSR senses and responds to environmental stress signals by upregulating gene expression for cell wall synthesis. A combination of enzyme kinetics, microbiological, and transcriptomic analyses revealed the mechanistic effect of the mutation on VraS and S. aureus. Michaelis-Menten kinetics show that the VraS mutation caused an increase in the autophosphorylation rate of VraS and enhanced its catalytic efficiency. The introduction of the mutation through recombineering coupled with CRISPR-Cas9 counterselection to the Newman strain wild-type (WT) genome doubled the minimum inhibitory concentration of three cell wall-targeting antibiotics. The mutation caused an enhanced S. aureus growth rate at sub-lethal doses of the antibiotics, confirming the causative effect of the mutation on bacterial persistence. Transcriptomic analysis showed a genome-wide alteration in gene expression levels and protein-protein interaction network of the mutant compared to the WT strain after exposure to vancomycin. The results suggest that the vraS mutation causes several mechanistic changes at the protein and cellular levels that favor bacterial survival under antibiotic stress and cause the mutation-harboring strains to become the dominant population during infection