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Examining The Challenges Of Providing Mental Health Treatment In Female Correctional Facilities From The Perspective Of Mental Health Professionals, Lacretia Williams

Walden Dissertations and Doctoral Studies

Women in correctional settings frequently experience significant mental health issues that are linked to histories of trauma, abuse, and victimization. Despite increased attention to trauma-informed and gender-responsive approaches, numerous obstacles continue to affect the delivery of mental health treatment within female correctional facilities. Existing literature focuses on systemic and policy concerns, overlooking mental health professionals' experiences. Guided by general systems theory, this qualitative study examined the challenges encountered by providers, including how organizational, environmental, and institutional factors influence treatment implementation. Data collected through semistructured interviews with 10 mental health professionals revealed multiple barriers to effective service delivery, including the complex …

Developing Field And Spaceflight Microscopy, Nikki Johnston

Dissertations and Theses

Designing for spaceflight favors the reduction of unnecessary features and cost-cutting, whether thisbe computation, hardware, or procedure. Resources are spent toward fortification and mission success over convenience. Such design goals paired with the relatively smaller budgets of academia lead us to do as much as we can in-house and use open-source as much as we can without compromising mission success. We also believe that thoroughly testing technology in extreme environments on earth is necessary for the success of a flight instrument. We focus on microscopy for life detection. I have spent my time here learning methods of hand-building microscopes to …

Viability Assessment Of Bovine Embryos: A Public Dataset And Deep Learning Baselines, Erfan Khayyati

All Graduate Theses and Dissertations, Fall 2023 to Present

Improving the success rates of cattle breeding is essential for sustainable agriculture, global food security, and high-quality livestock production. Currently, determining whether a lab-grown bovine embryo is healthy enough for a successful pregnancy requires highly trained experts to manually evaluate days of continuous time-lapse video footage. This process is not only incredibly time-consuming but also highly subjective; human reviewers often suffer from visual fatigue when tracking subtle, microscopic cellular changes over a seven-day period, leading to significant disagreement among even top experts on an embryo’s true potential. Furthermore, assessing bovine embryos is notoriously difficult due to their dark, lipid-dense cellular …

Modeling Intercellular And Intracellular Organization And Dynamics Of The Bacteria Escherichia Coli : From Population Dynamics In The Gut Microbiome, To Condensate Formation In Starved Cells, Alberto Alonso

Theses

Escherichia coli is a predominantly non-pathogenic species of bacteria present in the gut of most healthy adults. It plays a critical role in the health of the gut microbiome and is also widely used as a model organism in microbiology and synthetic biology studies. This thesis discusses results from two ongoing projects on E. Coli organization and emergent biophysical properties at two very distinct length scales. The first project focuses on using genetically modified engineered E. coli bacteria for early detection and intervention in colorectal cancer (CRC), a significant public health issue in the US. The success of these engineered …

Genetic Regulation Of Uterine Organogenesis, Diana A. Machado

Dissertations and Theses (Open Access)

In eutherian and marsupial mammals, the site of embryo implantation and gestation is the uterus. The precursor tissue of the uterus, oviducts, cervix, and upper vagina is the Müllerian duct epithelium and its adjacent mesenchyme. Morphological uterine variation between species is established during embryogenesis by species-specific differences in Müllerian duct fusion at the midline, growth, and differentiation. For example, laboratory mice have a bipartite uterus with two uterine horns and a single cervix, whereas humans have a simplex uterus with a single chamber and single cervix. In humans, variations in the fusion process can alter typical uterine morphology, correlating with …

Bridging Relational And Institutional Accountability: A Mixed Methods Study Of Implementing Sámi Ethical Research Guidelines In Finland’S Public Health Sector, Anna Charlotta Kihlstrom

Theses and Dissertations

The Ethical Guidelines for Research Involving Sámi People in Finland represent a critical step toward ethical Indigenous research; however, a gap remains between these principles and their implementation. This study responds to a research priority identified by the Sámi Social Affairs and Health Committee and examines how ethical research guidelines can be operationalized in the collaboration between the Sámi Parliament and the Finnish Institute for Health and Welfare (THL).

An exploratory sequential mixed methods design was employed, grounded in an Indigenous research paradigm and relational accountability. Extensive community engagement was carried out as a foundational part of the research methodology. …

Bivariate Current Status Data With Competing Risks Using Frailty Models, Biswadeep Ghosh

Doctoral Theses

Bivariate current status data with competing risks arises in many application areas, for example, carcinogenicity studies, epidemiological studies, reliability studies, etc..As par of our knowledge, bivariate current status data with competing risks has not received much attention in literature. We initiate this research focusing on modeling and estimation of quantities of interest in absence of any covariate. We model bivariate current status data with competing risks through different frailty structures in order to describe different kinds of association. We consider multiplicative frailty effect on different cause-specific baseline hazard functions. One important part of our analysis is to investigate the identifiability …

Synthesis And Evaluation Of Platinum (Iv) Prodrugs And Development Of Localized Drug Delivery Systems, Karla Cisneros Vargas

Electronic Theses and Dissertations Archive

This dissertation outlines the design, synthesis, and characterization of oxaliplatin-derived Pt(IV) prodrugs consisting of biologically active ligands. The stability and coordination behavior of oxaliplatin and a synthesized Pt(IV) derivative are investigated in an aqueous/organic mixed solution. Additionally, cytotoxicity of the compounds was tested using two human osteosarcoma cell lines, MG-63 and SK-ES-1. Notably, the tested drugs exhibited comparable or increased cytotoxicity compared to oxaliplatin. Another aspect of this research outlines the development and optimization of a triple-network hydrogel for the encapsulation and release of the hydrophobic drug Simvastatin. The hydrogel exhibited mechanical stability, biocompatibility, and biodegradability. Furthermore, it details the …

Bio-Inspired Visual Intelligence: Improving Efficiency And Robustness Through Foveal-Peripheral Sampling And Learned Saccades, Jiayang Liu

Dissertations - ALL

Deep neural networks have achieved state-of-the-art performance across a wide range of computer vision tasks, yet their deployment in real-world and safety-critical domains remains limited by two major challenges: vulnerability to adversarial perturbations and high computational cost. While adversarial training can improve robustness under certain threat models, it is computationally expensive and often generalizes poorly to black-box or transferable attacks. At the same time, conventional vision pipelines process uniformly sampled high-resolution images, introducing substantial data redundancy, latency, and energy overhead. In contrast, the human visual system achieves efficient and robust perception through space-variant foveal-peripheral sampling, attention-guided saccadic eye movements, and …

Statistical Methods For Mendelian Randomization Under Nonlinearity And Non-Normality, Mary Appah

ETDs from 2020-2029

Instrumental variable (IV) methods are widely used for estimating causal effects in observational studies where unmeasured confounding may bias traditional regression estimates. The core idea is to use a variable referred to as an instrument that is associated with the exposure of interest, independent of unmeasured confounders, and influences the outcome only through the exposure. While originally developed in econometrics, IV methods have been increasingly adopted in epidemiology and genetic research under the framework of Mendelian Randomization (MR), where genetic variants, most commonly single nucleotide polymorphisms (SNPs), serve as instruments. MR provides a powerful tool for investigating causal relationships between …

Data-Driven Approaches To Investigate Cardiotoxicity Using Hipscs High Throughput Screening, Danny Vu

Theses - ALL

Recent advances in human induced pluripotent stem cell (hiPSC) technology have enabled the development of high-throughput platforms for cardiotoxicity screening. However, conventional analytical approaches remain limited by time-intensive processing, manual annotation requirements, and reduced scalability for large datasets. To address these challenges, calcium fluorescence signals from human induced pluripotent stem cell-derived cardiomyocytes (hiPSC CMs) were analyzed using a high-throughput imaging platform and complementary machine learning frameworks. First, a feature-based supervised learning approach using engineered waveform descriptors and low-dimensional signal embeddings enabled rapid and interpretable screening of large chemical datasets, with combined features improving predictive performance relative to engineered features alone. …

"Respect Is Earned, Not Given": Analyzing Masculine Honor Ideology And Dominance And Prestige-Motivated Outcomes, Norah Rose Schloneger

Undergraduate Honors Thesis Collection

Masculine honor ideology is the idea that men act aggressively or violently toward women and others to achieve a masculine reputation. Previous research shows that men higher in masculine honor seek higher status and use prestige (e.g. respect, honor) or dominance (e.g. aggression, force) to achieve it. Using a variation of the prisoner’s dilemma—a game where participants are assigned to another player that they can choose to compete or cooperate with to maximize a point total—we analyzed behavioral outcomes of said motivations for men higher in masculine honor. We predicted that men higher in masculine honor using honor-dominance motivations would …

Design And Development Of A Perfusable Hydrogel Platform With Bioprinted Human-Endothelialized Microvascular Channels, Calvin A. Chernyatinskiy

All Theses

We developed an integrated bioprinting and perfusion platform to generate vascularized hydrogel constructs that support perfusable microchannel networks. Multiple hydrogel formulations, sacrificial ink systems, device geometries, and perfusion conditions were systematically evaluated to optimize print fidelity, mechanical stability, and cellular compatibility. Internally gelling alginate–calcium carbonate hydrogels were identified as a robust matrix, providing tunable gelation kinetics and structural stability during embedded printing. In parallel, Pluronic F-127 fugitive ink enabled reliable fabrication of continuous hollow channels due to its shear-thinning behavior and efficient post-print removal.

The finalized platform integrates stereolithographically fabricated perfusion chambers with extrusion-based bioprinting to produce three-dimensional, perfusable vascular …

Soil Microbial Responses To Artifical Light At Night, Randall L. Walker

Open Access Theses & Dissertations

Global change, driven by both natural processes and human activities, has significantly transformed ecosystems. Urbanization and artificial light at night (ALAN) are key contributors, disrupting natural light cycles and influencing biological rhythms, biodiversity, and ecosystem functions. Thus far, there remains a gap in knowledge of how soil ecosystems are impacted by ALAN. This study uses a laboratory incubation to investigate the effects of ALAN on soil microbial communities and functions across urban and natural ecosystems. Briefly, soil was collected from eight sites around El Paso, Texas and neighboring New Mexico representing urban and rural light exposure. Soil was then subjected …

Bptf-Dependent Regulation Of Vaccine-Induced B Cell Responses, Alexandria Sturtz

Arts & Sciences Graduate Student Theses and Dissertations

Vaccination is a method of safely generating highly specific, long-lived immunological memory that can protect a host upon future exposures to a pathogen. Memory B cells (MBCs) and high-affinity plasma cells (PCs) are pivotal populations generated during vaccine-induced immune responses as they provide rapid secondary immune responses upon antigen re-exposure. MBCs and PCs can both be produced by germinal centers (GCs), which are microanatomical structures where B cells undergo iterative rounds of somatic hypermutation and affinity-based selection. Regulation of the GC is complex and the network of factors that controls the identity, function, and magnitude of the GC B cell …

Organismic Encoding Of Geographic Information In Dna, Hema Siva Gayathri Dalavayi

Electronic Theses and Dissertations Archive

Recent evidence suggests that DNA also encodes information that reflects long-term environmental conditions. This work examines whether an organism’s genome encodes specific environmental information, and if so, what is its nature and origin. Genes from three insect groups, Simuliidae (blackflies), Lepidoptera (butterflies), and Formicidae (ants), were analyzed to address the geographic provenance (latitude, longitude) problem. DNA was converted into numerical signatures using noncrosshybridizing DNA bases and used to train machine learning (ML) models. Predictions achieved errors below the baseline, even for models trained on combined data without region-specific labels, indicating that DNA encodes this information and suggesting that the underlying …

Bio-Payload Senior Design Report, Connor Bishop, Oliver Goodall, Marcus Kirk, Gabby Robles, Anish Shanmuganathan

Interdisciplinary Design Senior Theses

This project focuses on the design and development of an autonomous experimental platform capable of conducting cellular biology experiments in a well plate within a CubeSat environment. The system integrates microfluidics, robotics, and onboard sensors to remotely initiate experiments, monitor them, and collect data without human intervention. The objective is to create a platform for automated biological experimentation in microgravity, while reducing reliance on ground-based control and increasing mission efficiency and reproducibility. The team used Saccharomyces cerevisiae to assess the biocompatibility of the well plate and monitor changes in cell culture, including optical density and cell viability.

Ferroptosis As A Pathological Driver In Niemann-Pick Disease Type C, Kayla Linda Sanchez

Loma Linda University Electronic Theses, Dissertations & Projects

Niemann–Pick Disease Type C (NPC) is a hereditary neurodegenerative disease characterized by selective cell vulnerability, particularly affecting cerebellar anterior Purkinje neurons. These neurons exhibit a distinctive pattern of degeneration due to the loss of NPC1 and/or NPC2 protein function, progressively extending towards posterior cerebellar regions. Historically, research has described NPC as a disorder of intracellular cholesterol handling; however, cholesterol-lowering therapies have not effectively prevented neurological deterioration, and the mechanisms underlying selective neuronal vulnerability remain unclear. Ferroptosis, previously referred to as oxytosis, is a regulated form of cell death driver by iron-induced lipid peroxidation. It has been implicated in several neurodegenerative …

Biomineralization Of Low Temperature Plasma(Ltp) Modified Polymeric Biomaterials And Scaffolds, John Patrick Bradford

ETDs from 2020-2029

Bio-integration, specifically osseo-integration of bone implants and scaffolds, are vital for the success of implants and bone tissue engineering (BTE). Calcification can be defined as the deposition of calcium compounds as either calcium phosphate(CaP) minerals consisting of hydroxyapatite(HAP) or CaP salts. The significance of the variety of phases of CaP is that mature bone matrix is composed of 65% CaP mineral. Many investigators have attempted to model the natural matrix by producing materials containing calcium phosphate in both amorphous CaP or in the more crystalline HAP form, with biomaterials (both synthetic and biological). Biomimetic CaP formation is a sign of …

Modulation Of The Cgas-Sting Inflammation Pathway In Mouse Models Of Accelerated And Slowed Aging, Benjamin David Heckman

ETDs from 2020-2029

Chronic sterile inflammation (inflammaging) is a core pillar of aging, and the cGAS-STING innate immune pathway has emerged as a key driver of this process. However, how this pathway intersects with systemic endocrine signaling remains poorly understood. Here, we investigated the intersection of endocrine signaling and cGAS-STING activation using two complementary mouse models with opposing lifespan phenotypes: a short-lived, liver-specific glucagon receptor knockout (LKO) mouse and a long-lived growth hormone-releasing hormone knockout (GHRH-KO) mouse. We demonstrate that despite presenting with a metabolically healthy phenotype, female LKO mice exhibited a significantly reduced lifespan. We link this premature mortality to a sex …

Development And Validation Of An Analytical Method For Quantitative Determination Of Small Aldehydes In Plasma, Stephanie T. Clark

Chemistry & Biochemistry Theses - Archive

Small aldehydes such as formaldehyde and acetaldehyde are highly reactive metabolites that play important roles in biological processes related to oxidative stress, metabolism, and DNA damage. Because of their chemical reactivity, volatility, and low endogenous concentrations, accurate measurement of these compounds in biological samples remains analytically challenging. The goal was to develop and evaluate a practical analytical method for detecting small aldehydes in biologically relevant matrices using headspace gas chromatography mass spectrometry (HS-GC-MS). The method combined chemical derivatization with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine (PFBHA) and headspace sampling to stabilize aldehydes and enable selective detection by mass spectrometry. Method development focused on optimizing derivatization …

Investigations Into Why Human (But Not Mouse) Ku70/80 Is Essential Reveal A Role For Human Ku70/80 In Ribosome Biogenesis, George Zakusilo

Student Theses and Dissertations

The requirement of Ku70/80 for ribosome biogenesis in higher primates explains otherwise perplexing essential nature of this double-strand break (DSB) repair factor. We have ruled out telomere protection or DSB repair as the essential function ofKu70/80. Instead, unbiased genome-wide analyses pointed to a role in ribosome biogenesis. Human Ku70/80, but not mouse Ku70/80 is enriched in the nucleolus at the Dense Fibrillar Component (DFC) periphery, likely via co-evolved protein-protein interactions with nucleolar factors. Consistent with its localization in the nucleolus, human Ku70/80 null cells exhibit ribosomal RNA (rRNA) processing defect and consequent shutdown of protein synthesis offer a direct explanation …

Loan-Heavy Aid: Consequences On Academic And Early-Career Outcomes, April Zhang

CMC Senior Theses

This study examines how the composition of financial aid, specifically the balance between loans and grants, shapes students’ academic performance, major selection, and early career outcomes. Using administrative data from the University of California system (2007-2019) and post-graduation records from UC Irvine, I analyze how loan reliance influences both educational trajectories and labor-market results. The key measure, loanshare, captures the fraction of total aid financed through loans rather than grants. This allows for comparisons among students with similar financial need, expected family contribution, and total aid levels. Results show that students with more loan-heavy aid packages earn significantly lower …

Commissioning & Daily Qa Of Converted Linac For Electron Flash, Tomaj Javidtash

Theses and Dissertations

Ultra-high dose rate (FLASH) radiotherapy has demonstrated promising normal tissue sparing in preclinical studies; however, the lack of standardized dosimetry, commissioning, and quality assurance (QA) methodologies remains a major barrier to its reproducible and safe implementation. In particular, conventional clinical commissioning and QA protocols are not directly applicable at FLASH dose rates due to challenges associated with detector response, dose-per-pulse effects, and beam control limitations.

This thesis presents the commissioning of a converted Varian 21EX linear accelerator for electron FLASH operation within the Division of Medical Physics at the Virginia Commonwealth University (VCU) Department of Radiation Oncology. Comprehensive beam characterization …

Application Of Paper Spray Mass Spectrometry For Screening Acetylcholinesterase Inhibitors, Diksha Gautam

Graduate Research Theses & Dissertations

Paper spray mass spectrometry (PS-MS) is a novel ambient ionization method that allows chemical and biological samples to be rapidly analyzed with little preparation being required. In this paper, PS-MS was set up and streamlined as an acetylcholinesterase (AChE)-monitoring platform in addition to screening an existing and newly produced AChE-inhibitors. The detection of the substrate, acetylcholine (m/z 146), and the AChE catalysis product, choline (m/z 104) was performed without applying chromatographic separation or derivatization to the dried paper substrates. Assay conditions were optimized in a systematic way, to develop a robust MS-compatible enzymatic workflow.

Calibration curves for both, acetylcholine and …

Semantic Discovery Of Genomic Datasets With Ai, Lawrence Allibah

Electronic Theses and Dissertations

Traditional keyword-based search in genomic databases often fails to capture the latent semantic context of biological studies, leading to a ``Lexical Gap" in research discovery. This thesis presents a high-performance dual-engine discovery system built upon 10,000 studies. By utilizing 1,536-dimensional vector embeddings, with large language models (LLMs) we implement a search engine coupled with a novel Hybrid Boosting layer that integrates semantic intent with factual metadata. Furthermore, we apply a high-dimensional K-Means clustering algorithm for unsupervised topic discovery. Empirical benchmarking demonstrates that the Hybrid Boosting engine achieves a 38.1% gain in precision and a 41.2% increase in Mean Reciprocal Rank …

Ecological And Evolutionary Divergence Of A Shared Sympatric Color Polymorphism In Paracirrhites Hawkfish, Samuel Greaves

Graduate Studies Theses and Dissertations 2026

Color polymorphism provides a tractable window into how selection, gene flow, and ecology interact to maintain phenotypic diversity and initiate divergence. I investigate the ecological and genomic basis of sympatric light and melanistic morphs in two reef hawkfishes, Paracirrhites arcatus and P. hemistictus, across Guam and Hawai‘i. This study aims to determine whether the color morphs of these hawkfishes are a stable polymorphism or have begun the process of ecological speciation. For P. arcatus revealed substantially lower density on Guam (0.086 ind/m²) than reported for Hawai‘i (0.292 ind/m²) and a strong skew away from the melanistic morph on Guam …

Volumetric Fluorescence Microscopy For High-Throughput And High-Sensitivity Imaging: From Single Molecules To Tissues, Le-Mei Wang

Graduate Studies Theses and Dissertations 2026

Fluorescence microscopy is an indispensable tool in the biological sciences, enabling researchers to investigate intricate subcellular structures, particularly for volumetric studies. However, conventional optical microscopy for volumetric imaging remains fundamentally constrained by imaging speed and throughput. To bypass traditional serial z-scanning, we introduce an axially scan-free method using a phase layer cake to modulate the system's point spread function. This approach projects volumetric information onto a 2D plane in a single shot, offering high flexibility in tuning axial depth alongside simultaneous multicolor imaging with high spatial resolution and sensitivity. This dissertation divides these technical advancements into cellular and tissue imaging …

Essays On Accelerated Failure Time Models For Recurrent Event Data, Emmanuel Masavo Djegou

Doctoral Dissertations

Recurrent event data arise in many fields such as medicine, reliability, insurance, and economics, where the same event may occur repeatedly for a subject. Accelerated Failure Time (AFT) models provide an intuitive framework for relating covariates to event times and offer a useful alternative to proportional hazards models, allowing direct prediction of event timing under right censoring. However, existing AFT extensions for recurrent events, such as accelerated gap time (AGT) models, often fail to account for interventions between events and may not capture complex temporal patterns.

In this work, we first propose a class of semiparametric AGT models incorporating an …

Semi-Supervised Learning For Annotation And Representation Of Single-Cell Rna Sequencing And Spatial Transcriptomics Data, Haoran Liu

Dissertations

Semi-supervised learning has emerged as a powerful paradigm for analyzing single-cell RNA sequencing (scRNA-seq) and spatial transcriptomics (ST) data, where full annotation is often costly or impractical. scRNA-seq technologies measure the expression of thousands of genes across tens of thousands of cells, whereas ST additionally captures the spatial coordinates of gene expression within intact tissue sections. Annotation is a key step in both scRNA-seq and ST analysis pipelines, aiming to identify cell types, spatial domains, and latent biological structures. However, most existing annotation approaches rely on separate clustering methods that are typically fully unsupervised and fail to leverage side information …