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The Challenges Of Lesbian Senior Leaders In The Army Branch Of The Department Of Defense, Ella Nunley-Spaights

Dissertations

Purpose: The purpose of this phenomenological study was to explore the perceptions of lesbian senior leaders and the types of challenges they experience while serving in the Army Branch of the Department of Defense. A secondary purpose of this study was to identify strategies lesbian senior leaders employ to overcome perceived challenges while serving in the Army Branch of the Department of Defense.

Methodology: This phenomenological study described the lived experiences of seven lesbian senior leaders serving in the Army who were retired from service within the past five years. Convenience and snowball sampling were utilized to identify women who …

Dames Paving Pathways To Directorships. A Study About Female Leaders In Art Museums In The United States, Mechele Manno

Dissertations

Purpose: The purpose of this qualitative phenomenological study was to examine and describe the career pathways of female art museum directors in the United States

Methodology: This phenomenological study described lived experiences of eight female art museum directors with over five years of directorship experience from museums with operating budgets over $10 million and in states that receive the highest private funding: CA, DC, IL, MA, NY, OH, PA, and TX. Data collection consisted of in-depth interviews using a scripted interview guide in research categories: a) motivation; b) career advancement; c) barriers; and d) support.

Findings: All major findings were …

Feature Augmentation For Improved Topic Modeling Of Youtube Lecture Videos Using Latent Dirichlet Allocation, Nakul Srikumar

Dissertations

Application of Topic Models in text mining of educational data and more specifically, the text data obtained from lecture videos, is an area of research which is largely unexplored yet holds great potential. This work seeks to find empirical evidence for an improvement in Topic Modeling by pre- extracting bigram tokens and adding them as additional features in the Latent Dirichlet Allocation (LDA) algorithm, a widely-recognized topic modeling technique. The dataset considered for analysis is a collection of transcripts of video lectures on Machine Learning scraped from YouTube. Using the cosine similarity distance measure as a metric, the experiment showed …

Behavioral Motivation Of High School Leadership Organizations, Jake Kloeppel

Dissertations

This quantitative research study examined the perceptions of ninth through 12th grade leadership students and facilitators, regarding their motivation to project-based learning scenarios. Electronic surveys requesting approximately 180 participants were sent to five school districts from three counties in Central Missouri. A total of 203 participants chose to respond to the survey, Motivation Questionnaire (MQ; Phillips & Gully, 2013), consisting of 15 Likert-scale items and one optional, open-ended question, which was designed using McClelland’s Human Motivation Theory (1987). The results of this study showed there were only minimal differences in the motivation to projectbased learning scenarios between members of multiple …

Self-Efficacy And Self-Regulation As Predictors Of Academic Motivation Among Undergraduate Students In The United States, Fatimah Aljuaid

Dissertations

Problem

Some undergraduate students demonstrate lack of academic motivation which negatively affects engagement and perseverance in higher education (Busse & Walter, 2017; Rizkallah & Seitz, 2017; Dresel & Grassinger, 2013). Amotivated students are more likely to drop out of school and disengage from learning activities or underachieve (Wang & Pomerantz, 2009). Although the lack of academic motivation is correlated with deficiency in self-regulation and self-efficacy, relatively little studies have been conducted to examine the impact of these factors on academic motivation particularly in the U.S. This study constructed a hypothesized model to investigate the role of self-regulation and self-efficacy in …

Chemical Oxidation And Photoinduced Electron Transfer By Nickel And Copper Complexes, Niharika Krishna Botcha

Dissertations

The energy appetite of our global society is enormous with the need only expected to double by midcentury and triple by 2100. The global energy demand calls for diversifying our energy sources and relying more on sustainable energy resources. Transition metals are ubiquitous in nature and central to many organic and biochemical transformations. Activation and catalytic conversion by multielectron redox reactions are crucial for the production of fuels (e.g., hydrogen) or useful chemicals (e.g., organic compounds). In this dissertation we will present our efforts on finding catalysts that can do organic transformations under ambient conditions. We also investigated different multi-component …

Engineering And Functional Modification Strategies For T Lymphocytes Using Therapeutic Macromolecules, Polymers, Micro And Nanoparticles, Venkata Sesha Sai Abhinav Ayyadevara

Dissertations

T cells are crucial components of the adaptive immune system and are known for secreting various cytokines, which induce the proliferation of many immune cells, including T cells themselves. A subset of T cells, called the CD8+ T cells, are known for their ability to kill infected cells and cancer cells. Naturally, the potential in using T cells for immunotherapy of cancer is tremendous. For this purpose, however, it is often required to engineer T cells specifically to treat a particular type of cancer. For example, the FDA-approved immunotherapies, KymriahTM and YescartaTM, which come under the adoptive T cell therapy, …

The Effects Of Altitude On The Aerodynamic Performance Of Monarch Butterflies, Madhu Kandikere Sridhar

Dissertations

The aerodynamic efficiency behind the annual migration of Monarch butterflies, the longest migration among insects, is an unsolved mystery. Monarchs migrate 4000 km at high altitudes to their overwintering locations in the mountains of Central Mexico at an altitude of 3000 m. The air is thinner at higher altitudes, yielding reduced aerodynamic drag and enhanced range. However, lift is also expected to decrease in lower density conditions. The objective of this research is to test the hypothesis that aerodynamic performance of Monarch wing improves at reduced density conditions at higher altitudes. First, we experimentally measured and documented the wing and …

Solving The Continual Improvement And Innovation Challenge For The Benefit Of Patients: How An Effective Pharmaceutical Quality System (Pqs) And Risk-Based Approach Could Transform Post-Approval Change (Pac) Management, Emabelle Ramnarine

Dissertations

Patients deserve their medicines on time every time. Regulators safeguard public health by ensuring availability of safe, effective, high-quality medicines. Pharmaceutical companies must continually improve and innovate to deliver such medicines. In spite of these patient-centric objectives, drug shortages have continued to grow as a global public health concern. The drug shortage problem has existed for decades though there has been no shortage of effort, recommendations, papers, and expectations to resolve it. During the ongoing COVID-19 pandemic even exceptional measures were rapidly implemented to prevent shortages, yet no long-term solutions have been found.

This research hypothesis was that due to …

Performance Comparison Between A Distributed Particle Swarm Algorithm And A Centralised Algorithm, Ciarán O’Loughlin

Dissertations

Particle Swarm optimisation (PSO) is a particular form of swarm intelligence, which itself is an innovative intelligent paradigm for solving optimization problems. PSO is generally used to find a global optimum in a single optimisation function. This typically occurs on one node(machine) but there has been a significant body of research into creating distributed implementations of the PSO algorithm. Such research has often focused on the creation and performance of the distributed implementation in an isolated manner or compared to different distributed algorithms.

This research piece aims to bridge a gap in the existing literature, by testing a distributed implementation …

Effects Of Altering Variable, Basic Residues Of Ribosomal Proteins Ul4 And Ul22 Facing The Ribosomal Exit Tunnel On Growth, Resistance,And Gene Expression In Escherichia Coli: Focus On Ul22 K90d, Elizabeth A. Franklin

Dissertations

Mutational changes in bacterial ribosomes that confer antibiotic resistance decrease cell fitness. Determining the genetic factors that interconnect antibiotic resistance and cell fitness is critical in the fight against bacterial infections. This study describes gene expression and phenotypic changes presented in Escherichia coli cells carrying a uL22 K90D mutant ribosomal protein, which showed growth defects and resistance to macrolide antibiotics. Other uL4 and uL22 mutation, in basic, non-conserved residues, were examined for phenotypic changes, however the uL22 K90D mutation displayed the most consistent phenotypes when compared to the wild type strain, and thus was the focus of this study. Ribosome …

Coping Skills, Emotional Intelligence, Attachment, And Resilience On Post-Traumatic Stress Disorder In Private Sector Emergency Medical Technicians, Brenda-Joyce Gonzales Orozco Markert-Green

Dissertations

Problem

Private sector Emergency Medical Technicians (EMTs) are first responders who respond to traumatic incident scenes along with firefighters and police officers. However, news agencies and the public do not acknowledge private sector EMTs with the same vigor or accolade as public sector EMTs, nor are the risks to life, health, and mental well-being recognized among this population. Thus, the research literature has been sparse regarding how private sector EMTs experience PTSD, and what unique risk factors and needs may be present.

Purpose Statement

The purpose of this study was to examine the relationship between PTSD symptoms and coping skills, …

An Exploratory Study Of Mathematics Anxiety In Caribbean Preservice Teachers, Franka Atwell-Chin Hong

Dissertations

The Problem

Correlational studies suggest that gender, attitudes to mathematics, mathematics performance, the number of college mathematics courses taken, and mathematics teacher efficacy beliefs may be related to mathematics anxiety among preservice teachers (Boyd et al., 2014; Gresham, 2018; Jaggernauth & Jameson-Charles, 2015). Exploratory studies of mathematics anxiety and teacher self-efficacy among elementary teachers exist in Trinidad and Tobago (Jaggernauth 2012; Jaggernauth & Jameson-Charles, 2015). However, the differences in samples, and weakness in methodology, may make it challenging to generalize the results to the preservice teacher population. In addition, no studies have found which variable or combination of variables is …

Characterizing Galectin And Lysosomal Rupture's Role In Spreading Parkinson Disease Pathology, Kevin Burbidge

Dissertations

The misfolding and subsequent accumulation of alpha-synuclein (α-syn) is central to the pathogenesis of Parkinson's disease (PD). Several lines of evidence suggest pathological α-syn spread cell-to-cell via a "prion-like" mechanism. Furthermore, this pathological α-syn is capable of "seeding" further misfolding of non-pathological α-syn, converting them to the pathological form. While a vast body of both genetic and experimental evidence indicates that α-syn is critical to PD development, how α-syn induces progressive neuronal dysfunction and cell death remains unclear.Autophagy, conventional for macroautophagy, is the primary degradation pathway for α-syn aggregates. Autophagy also influences the unconventional secretion of both pathological and non-pathological …

Molecular Determinants Of Fetal Tolerance And The Transition To Adult Immunity, Yi Wei Lim

Dissertations

The perinatal immune system is highly tolerogenic and is phenotypically and functionally distinct from the adult immune system. This tolerogenic nature is a double-edged sword for newborns. While it is beneficial to prevent excessive inflammation against the vast array of foreign antigens encountered after birth, it also causes a lack of immune responses to life-threatening infections. My dissertation research aims to investigate the mechanisms by which perinatal T cells contribute to immune tolerance in infants. A deeper understanding of the nature of the perinatal immune system will provide pivotal knowledge to develop safe and effective strategies to protect infants from …

Time Wavelength Optical Sampling Spectroscopy, Srikamal Jaganraj Soundararajan

Dissertations

Real-time optical spectroscopy capable of tracking fast and rare events has attracted considerable interest in recent years due to its potential to significantly impact the study of chemical and biological reaction dynamics. However, the development of such capabilities faces major challenges in terms of instrument response time, spectral resolution, and power sensitivity. In this dissertation, a new spectroscopy method called time-wavelength optical sampling (TWOS) spectroscopy is proposed, analyzed, and experimentally demonstrated. This method combines the advantages of time-stretch spectroscopy (TSS) and ultrafast optical sampling, and offers several key benefits over conventional TSS based on direct power measurement. By developing a …

Il-27 Signaling In The Maintenance Of Intestinal Barrier Following Ethanol Intoxication And Burn Injury, Marisa Luck

Dissertations

Roughly half of burn patients that are hospitalized in the United States each year have detectable blood alcohol levels. Alcohol intoxication at the time of burn injury leads to worse outcomes, including longer hospital stays, increased rates of infection, and death. One of the severe consequences of intoxication and burn injury is the disruption of the gastrointestinal (GI) tract, which houses the largest reservoir of bacteria in the human body. Leakiness of the gut barrier can contribute to inflammation, infection, or sepsis from gut-derived microbes. Interleukin-27 (IL-27) is a cytokine that has shown some beneficial effects in other models of …

Comparative Studies On Biochemical And Pharmacological Profiles Of Unfractionated Heparins & Their Depolymerized Derivatives From Bovine, Ovine And Porcine Origins, Ahmed Kouta

Dissertations

Heparin and heparin related drugs have remained the anticoagulant of choice for medical and surgical indications. These drugs are comprised of poly-component sulfated chains of varying length and biophysical structure with direct and indirect pharmacological effects. Heparins produce their therapeutic effects by multiple mechanisms involving both the cellular and humoral targets. These drugs represent natural products which are isolated from mammalian tissue rich in mast cells. Currently used heparin and LMWHs are obtained from porcine mucosal tissue. Other animal sources including bovine and ovine tissues also provide additional sources for the manufacturing of heparins. While there may be microchemical and …

F Plasmids In Escherichia Coli Decrease Permissivity To Coliphage, Cesar Eber Montelongo Hernandez

Dissertations

The urinary tract contains a community of bacteria called the urinary microbiota (urobiota) thatmay be relevant to health; the genomic component of the urobiota is the urinary microbiome (urobiome). Urinary bacteria have been associated with both asymptomatic states and disease conditions, such as urinary tract infection (UTI), overactive bladder (OAB), and urge urinary incontinence (UUI). Some bacteria, such as E. coli, are considered urinary pathogens (uropathogens) but also can be commensals. Bacteriophage (phage) are ubiquitous in nature and likely shape bacterial populations in every niche; thus, phage may be one factor that modulates the urobiota. Phages have a specific host …

Equity In Secondary Schools: Building A Strong Sense Of Belonging For Students Of Color As A Foundation For Academic Success, Joaquin Stephenson

Dissertations

The problem of practice I am investigating are students who identify as Black and Latinx who are experiencing a statistically significant low sense of belonging at Riverview High School in comparison to their White and Asian counterparts, based on survey data for the past two years. Research has shown that students’ sense of belonging stem from four major factors (1) friendship nominations, (2) time on extracurricular activities, (3) bonding with teacher, and (4) perceived discrimination. By focusing on targeted programming, this study aims to determine the two solutions that can target low sense of belonging for Black and Latinx students. …

Emancipatory And Controlling: Examining The Negotiation Of Masculinity-Centered Practices By Women's And Gender Equity Center Practitioners, Ashley M. Brown

Dissertations

Initiatives to understand and transform masculinity have increasingly emerged in higher education, calling attention to the consequences of dominant, masculine gender expectations that permeate throughout college campuses. These masculinity-centered practices in higher education encompass formalized, departmental initiatives for students, faculty, and/or staff that examine topics related to masculinity through educational workshops, speaker events, professional development sessions, dialogue spaces, and other efforts. While it is often assumed that these practices support the advancement of gender equity, scholars have theorized the ways in which this work can also lead to depoliticized efforts that may, in fact, reify patriarchal and other systems of …

Peace Bodies: Women, Encampments, And The Struggle Against Nuclear Weapons During The Cold War, 1979-1992, Janette Clay

Dissertations

"Peace Bodies: Women, Encampments, and the Struggle against Nuclear Weapons during the Cold War, 1972-1992" examines the global 1980s women's peace camping movement. This study aims to explore and comprehend peace in new ways. It is specifically targeted to define peace campers' fundamental peace principles and to discover how they embodied them. This research interrogates the ways in which the peace camping movement influenced the political and cultural developments that led to nuclear de-escalation in the final years of the Cold War. The sources for this research include women's peace camp archival records, film footage and photographs, interviews, and oral …

Examining The Interplay Of Mental Health, Family Conflict, And Body Mass Index Among Mexican Origin Families: A Cross-Lagged Model, Laura Margaret Lehman Distel

Dissertations

Mexican-origin youth in the U.S. are at risk for obesity (Fryar et al., 2018) and mental health concerns (McLaughlin, Hilt, & Nolen-Hoeksema, 2007). One key psychosocial process implicated in this health inequity is family conflict (Conger et al., 1999), which has been associated with both poor mental health outcomes (e.g. Santiago & Wadsworth, 2009) and overweight and obesity (Halliday et al., 2013). However, no research to date has examined the complex interplay of family conflict, mental health problems and body mass indices (BMI) over time. The present study examined cross-lagged associations among child z-scored BMI (zBMI), mental health problems (internalizing …

Impact Of Violence Exposure On Children's Mental Health And Family Functioning: An Ecological-Transactional Approach, Rice Mary Dusing

Dissertations

N/A

Development Of Small Molecule Inhibitors Of Therapeutic Target Enzymes: Paths To Discover Novel Antimicrobials, Thahani Shifna Habeeb Mohammad

Dissertations

The rising antimicrobial resistance to antibiotics is a major global problem, which has been exacerbated by the inappropriate use of antibiotics. The effectiveness of frequently prescribed penicillin derivatives and β-lactamase inhibitors are compromised by the evolution of bacterial β-lactamases and antibiotic-resistant bacteria. Consequently, design and synthesis of small-molecule inhibitors of identified novel antibiotic targets is an urgent unmet medical need. We previously demonstrated that N-functionalized α-aminocyclobutanones can act as peptidomimetic enzyme inhibitors, including inhibition of a key esterase in Francisella Tularensis. The carbonyl of a cyclobutanone is electrophilic due to ring strain, therefore cyclobutanone derivatives can serve as transition state …

The Role Of The Co-Chaperone Protein Bcl-2-Associated Athanogene 3 (Bag3) At The Cardiomyocyte Sarcomere, Thomas Gwynn Martin

Dissertations

The co-chaperone protein Bcl-2-associated athanogene-3 (BAG3) is a central mediator of cellular protein quality control through autophagy. In the heart, decreased BAG3 activity through mutation or decreased expression are linked to dilated cardiomyopathy (DCM). Unfortunately, though clinical data indicates BAG3 mutations are a definitive cause of DCM, few mechanistic studies had been performed to decipher the fundamental role of BAG3 in cardiomyocytes. However, several studies suggested BAG3 was involved in maintenance of the sarcomere, the molecular contractile structure in muscle cells. The goals of this dissertation were to: 1. Determine the functional significance of BAG3 for the sarcomere, 2. Identify …

Cardioprotective Extracellular Vesicles Derived-Micrornas: Sorting Mechanisms And Functions, Anh P. Phan

Dissertations

Extracellular vesicles (EVs) are nano-size membrane bound vesicles that are derived from the fusion of multivesicular endosomes with the plasma membranes. EVs have important roles in intercellular communication through the transfer of their unique cargoes including RNA, DNA and protein molecules to recipient cells. Mesenchymal stem cell (MSC)-derived EVs have been shown to reduce infarct size and reduce the progress of heart failure after cardiac ischemia/reperfusion (I/R) injury in animal models. Small non-coding RNAs such as microRNA (miRNA) have been indicated as one of the active components that mediate the beneficial effects of MSC-derived EVs. However, the selective packaging mechanisms …

Synthesis And Characterization Of Redox Non-Innocent Ligand Supported Transition Metal Complexes, Adriana Marie Lugosan

Dissertations

Catalysis is an integral part of society, which is often taken for granted. Over the past few years, there has been an increased effort to develop catalysts that are more environmentally friendly, selective, and energy efficient. This work focuses on the development of novel complexes made from a carefully designed non-innocent ligand together with earth-abundant and cost-effective transition metals that can be used to understand fundamental inorganic chemistry principles and serve as model systems. The work reported within validates the utility of this novel class of redox non-innocent ligand to form metal complexes with interesting properties, such as a non-porphyrin …

Identification And Characterization Of Calcium As A Biofilm Promoting Signal By Vibrio Fischeri, Alice Hannah Tischler

Dissertations

The marine bacterium, V. fischeri actively engages in an exclusive partnership in the light organ of its squid host, Euprymna scolopes. A critical step in this colonization process is the formation of a bacterial aggregate, or biofilm, which is a community of bacteria embedded within a protective extracellular matrix. While V. fischeri readily forms biofilms in nature, genetic overexpression must be utilized to achieve biofilm formation in the laboratory. Recent work investigating media composition led myself and others to evaluate how seawater salts impacted growth and biofilm formation in a number of mutant backgrounds, leading to the identification of calcium …

Analysis Of Regulatory Mechanisms For T Cell Activation, Aleksandra Vuchkovska

Dissertations

The primary function of the immune system is to seek and eliminate altered or unhealthy cells. T cells are a major component of the immune response and mediate their functions by recognizing specific antigens that allow elimination of infected or neoplastic cells. To avoid inappropriate activation and subsequent immune injuries, T cells have evolved strategies to discriminate self from non-self, or healthy from altered and infected. These strategies rely on the activation of receptors that restrict the T cell response. CD33rSiglecs are a family of mostly inhibitory receptors that bind to sialic acids. Siglecs respond to specific sialic acid patterns …