Hafnium Oxide-Based Nanoheterostructures For Catalytic Radiosensitization And Enhanced X-Ray Radiotherapy, Marlen Dariela Calix Quezada

Theses and Dissertations

Orthovoltage X-ray beams are attractive for surface and intra-operative radiotherapy. Yet, their clinical utility is constrained by rapid attenuation and the limited dose that can be delivered without harming healthy tissue. High-Z hafnium oxide (HfO₂) nanoparticles can boost local energy deposition through the photoelectric effect, while catalytic surface defects accelerate water radiolysis. Harnessing both mechanisms in a single nano-heterostructure could enable potent radiosensitization at diagnostic-range energies.

This thesis develops and evaluates HfO₂-based nanoheterostructures, both bare and Au-decorated, as catalytic radiosensitizers.

Two types of HfO₂ were evaluated, one was synthesized following a specific route and the …

Targeting The Achilles’ Heel Of Lung Cancer Induced By Oncogenic P53, Brandon G. Velasco

Theses and Dissertations

Mutations of the tumor suppressor gene, TP53, are the most prevalent oncogenic mutations in lung cancer, occurring in up to 70% of human non-small cell lung cancer (NSCLC). The majority of mutations in p53 are missense mutations that cause not only a loss of tumor suppressor function, but also gain of oncogenic functions, like tumorigenicity, immune suppression, and chemoresistance. Previous studies have shown that the depletion of gain-of-function (GOF) p53 or disruption of its ability to transactivate the expression of genes related to oncogenesis eliminates its tumorigenic properties indicating a dependency of human lung cancer cells expressing GOF p53 …

Enhancing Clinical Trial Matching In Molecular Diagnostics: Using Natural Language Processing And Clustering Approaches In Hematological Malignancies, Gillian Fanning

Theses and Dissertations

Clinical trial matching is a critical component of personalized medicine, particularly in the management of hematologic malignancies. At Virginia Commonwealth University (VCU) Health, the Molecular Diagnostics (MDX) Lab produces somatic variant reports and recommends clinical trials based on the presence of clinically significant mutations. However, the current manual trial recommendation process is time-intensive and lacks scalability.

This study introduces a computational framework to streamline and standardize clinical trial matching using natural language processing (NLP) and unsupervised clustering. Trial brief descriptions were analyzed to extract frequent terms, and trials were grouped based on term similarity using joint dimensionality reduction and clustering. …

Developing Bioinformatics Expertise Through The Annotation Of The Gut Microbiome Of Odontotaenius Disjunctus, Keidra E. Carter

Theses and Dissertations

Next-generation sequencing (NGS) technologies have revolutionized biological research by generating unprecedented volumes of genomic data, necessitating advanced bioinformatics tools and specialized expertise to fully interpret complex microbial communities. This study outlines an integrated workflow to characterize the gut microbiome of the wood-feeding beetle Odontotaenius disjunctus. Prokka is employed for functional annotation to identify protein-coding genes and other genomic features, while Kaiju is used for taxonomic classification. DIAMOND is then applied to locate and validate the taxonomic assignments generated by Kaiju by aligning sequences within the contigs to a comprehensive protein database, proGenomes. Functional analysis revealed that the contigs encode proteins …

Health Equity In Times Of Crisis: The Impact Of Economic And Public Health Shocks On Access To Care Among Women In Zimbabwe And The United States, Vimbainashe Dihwa

Theses and Dissertations

Abstract

This dissertation examines health equity during times of national public health and economic crises by examining access to care among women of reproductive age. Papers 1 and 2 estimate the effects of the 2020 Covid-19 pandemic in the United States (US). Paper 3 examines the potential effects of the 2008 hyperinflation and subsequent economic crisis in Zimbabwe.

Paper 1 assessed the role of health professional shortage areas (HPSAs) in the Covid-19 pandemic-related temporal trends in mental health access among women in the 18 to 44 years age group with self-reported anxiety and/or depression. The findings suggest decreased unmet prescription …

Climate Change-Induced Shifts In Mediterranean Fungal Fruiting Phenology And Productivity, Rachel Demay

Theses and Dissertations

We used a 29-year dataset of mushroom fruiting from the Pinar Grande forest in northern Spain to investigate the effects of climate change on the phenology, productivity, and diversity of mycorrhizal and saprotrophic mushrooms. We investigated the long-term trends in fruiting season length, yield (by count, total weight, and average weight), and genus richness. Additionally, we identified associations between monthly temperature and monthly precipitation with these fungal responses across functional groups: mycorrhizal, saprotrophic, litter-decaying saprotrophic, and wood-decaying saprotrophic mushrooms, and the economically-important edible genera Boletus and Lactarius. We found that autumnal season length in the Pinar Grande has shortened over …

An Exploration Of The Relationship Between School Counselor Access And Latine Students’ College-Going Behaviors, Kristen Tuxbury

Theses and Dissertations

This study examined the relationships between school counselor access and Latine students’ college-going behaviors using data from the High School Longitudinal Study of 2009 (HSLS:09). The study was guided by critical race theory and Yosso’s community cultural wealth model (2005). Binary logistic regression models, Chi-square tests of independence, and descriptive statistics were used to explore the associations between school counselor access, Latine student college-going behaviors, and caregiver expectations. The findings show stronger associations between caregiver expectations and Latine student college-going behaviors than school counselor access. Additionally, findings provide evidence that experiences of oppression are likely barriers to Bachelor’s degree programs …

Integration Of Phenotyping Into A Preliminary Investigation Of Stand-Alone Web-Based Cognitive Behavioral Therapy Among A Non-Treatment Seeking Sample, Anna B. Parlier-Ahmad

Theses and Dissertations

Alcohol use disorder (AUD) is the most common substance use disorder. However, most people with AUD do not receive treatment. Among those who do, it is only moderately effective largely due to the heterogeneity of people with AUD. Many of these individuals, particularly those with mild AUD, can reduce or cease alcohol use without specialized treatment. However, efforts to refer those with more severe AUD to community residential or outpatient programs have been largely unsuccessful, especially among women who often face practical barriers like lack of transportation and childcare. Technology offers innovative opportunities to make treatment more readily accessible to …

Rehabilitation In Stroke-Related Flexor Synergy, Shawn J. Dirocco

Theses and Dissertations

Upper extremity abnormal flexor synergy caused by stroke can impair individuals by coupling upper extremity muscles with deltoid activation. Previous studies have shown that reduction in deltoid loading can decrease flexor synergy. Robotic rehabilitation has the ability to allow for reduced deltoid loading while assisting or constraining joints along the arm to increase rehabilitation outcomes. The effects of higher degree of freedom low impedance robotics needs to be tested to learn how various parameters affect flexor synergy in comparison to end point robotics. During the first experiment, we tested 16 chronic stroke patients with flexor synergy problems in 3 tasks. …

Trauma-Informed Beliefs And Our Child Welfare System, Gabriela Ana Aisenberg

Theses and Dissertations

The integration of trauma-informed care (TIC) into behavioral health and child welfare systems has garnered increasing attention, reflecting a growing acknowledgment of the pervasive and multifaceted impacts of trauma on individuals, families, and service delivery structures (Barnett et al., 2019; Bartlett et al., 2018; Bassuk et al., 2017; Substance Abuse and Mental Health Services Administration [SAMHSA], 2014). Legislation such as the Family First Prevention Services Act (FFPSA) has led to increased adoption of trauma-informed practices through increased funding for training and services (Bowen & Murshid, 2016; Brown et al., 2023). Research shows that providers’ understanding and implementation of TIC is …

Machine Learning Models Leveraging Patient-Similarity And Clinical Temporality For Disease Prognoses, Ahmad F. Al Musawi

Theses and Dissertations

Electronic Health Records (EHRs) constitute a comprehensive and high-dimensional repository of clinical data, encompassing a wide array of patient-level information such as diagnoses, procedures, medications, laboratory results, and unstructured clinical narratives. These data hold immense potential for advancing predictive modeling in healthcare, including tasks such as disease progression modeling, hospital readmission prediction, and length of stay (LoS) estimation. However, the intrinsic complexity of EHR data—manifested in its heterogeneity, sparsity, and temporal dynamics—poses significant analytical challenges that limit the generalizability and interpretability of conventional machine learning models. Recent methodological advancements in deep learning and graph-based learning, particularly Graph Neural Networks (GNNs), …

Treatment Resistant Obesity Among Midlife Women Receiving Care From A Specialized Weight Management Clinic, Emily C. Stevens

Theses and Dissertations

Background: Obesity is a complex chronic disease that conveys significant health risk. Women with obesity are at greater risk for associated conditions including heart disease, hypertension, ischemic stroke, and sex-specific cancers compared to their male counterparts. Midlife may present unique challenges for women as it is during this life phase that they experience an increase in their overall obesity prevalence and severity. Some midlife women experience treatment resistant obesity (TRO), a phenomenon not previously explored in the research literature, conceptualized as failure to achieve clinically meaningful weight loss of ≥ 5% after having received medically specialized obesity care for one …

Visible Modulation Of Epsilon Near Zero Materials, Jonathan M. Weber

Theses and Dissertations

While Epsilon-Near-Zero materials have offered many benefits from their introduction to the field of nonlinear optics, those materials have also narrowed the range of wavelengths often studied. With reliable and proven enhancements to light-matter interaction in the ENZ region, many researchers have had little reason to extend the spectrum measured in experiments. The purpose of this work is to measure the intensity dependent refractive index of Indium Tin Oxide across a broad spectral range, from ultraviolet to near infrared, to improve the understanding of semiconductor nonlinearities far from Lorentz and Drude resonances. Furthermore, the visible region is naturally low-loss in …

Characterization Of Nanoplastic-Induced Exacerbation Of Asthmatic Pathophysiology In A Murine In Vivo Model, Keith Li

Theses and Dissertations

As global plastic production increases, so does the environmental and biological presence of nanoplastics (NPs), raising growing concerns about their potential impact on human health. These particles have been detected in various organs, including the lungs, yet their role in respiratory inflammation remains largely unexplored. Emerging evidence suggests that NP exposure may influence immune responses in the lungs, particularly in individuals with preexisting conditions such as asthma. However, the specific ways in which these particles interact with allergen driven inflammation are still unclear.

In this study, a murine model of allergic airway inflammation was used to investigate how surface modified …

Rare Variant Analysis Of Electronic Health Record-Defined Major Depressive Disorder In The All Of Us Research Program, Stephen Emil Vieno

Theses and Dissertations

The underlying pathogenesis of MDD remains poorly understood, with multiple competing hypotheses regarding its exact etiology. As a heterogeneous disorder with relatively low heritability, large-scale genome-wide association studies of MDD have relied on increasingly large sample sizes to identify common genetic variants associated with the disorder. However, the rare variant genetic architecture of MDD is still largely unknown. The aim of the present analysis was to use the AoU—a United States-based biobank that integrates healthcare records from over 50 healthcare systems and possesses whole genome sequencing data for participants—to perform a gene set–based analysis of MDD. This analysis presented several …

Bugs In The Flux: Links Between Arthropod Diversity And Spatial Variation Of Soil Respiration In A Temperate Forest, Erin-Darby H. Mcclain

Theses and Dissertations

Soil respiration (Rs) is the largest terrestrial flux of carbon (C) to the atmosphere, with heterotrophic contributions to Rs varying spatially and temporally. While microbes are the primary and most thoroughly studied source of soil heterotrophic respiration (Rh), contributions from higher trophic organisms, including arthropods, are rarely quantified and poorly understood. Arthropod abundance and diversity correspond with variation in soil microclimate, which is influenced by site factors including canopy structure, site productivity, and disturbance. However, the extent to which these site factors influence arthropod abundance and diversity, and consequently, spatial variation in Rs is not known. The objective of our …

Associations Between Community Violence Exposure And Internalizing Outcomes: The Moderating Role Of Racial Identity, Kimberly S. Lazarus

Theses and Dissertations

Community violence continues to be an ongoing public health crisis, driven by structural inequities and systemic disinvestment. Due to historical discriminatory policies and ongoing systemic barriers, Black adolescents are disproportionately affected, placing them at heightened risk for adverse mental health outcomes, particularly post-traumatic stress symptoms (PTSS) and depressive symptoms. While existing literature highlights racial identity as a promotive factor linked to a lower likelihood of negative health outcomes, less is known about its protective role in buffering the mental health effects of adversity. There is an increasing call for public health researchers to consider racial-ethnic factors as potential moderators in …

Hyperreality Ain’T Really Real: Postmodernity, Social Media, & Blackness, Micah White

Theses and Dissertations

This qualitative study examines the interplay between postmodernity, social media, and African American identity formation through focus group analysis and Grounded Theory methodology. The research investigates how social media’s postmodern features—fragmentation, hyperreality, commodification, and context collapse—shape identity development among African Americans, who historically navigate cultural disruption and systemic racism. Data from semi-structured interviews with two generational focus groups revealed that participants engaged in sophisticated identity curation to balance authenticity and protection in racially charged digital spaces. Key findings highlight the tension between empowerment and marginalization, as social media served as both a platform for racial affirmation and a source of …

A Multimethod Approach To Examining Racial Coping Socialization Among Black Adolescents, Rachel J. Davis

Theses and Dissertations

Experiences of racial discrimination are pervasive in the lives of Black youth and result in race-related stress. Racial coping has been found to mitigate the negative physical and mental health effects of racial discrimination; thus, it is imperative that we understand the process that Black youth undertake to navigate racialized experiences by utilizing a person-centered approach. Additionally, parents socialize their Black youth to navigate racialized experiences, indeed, previous research has investigated racial and emotion socialization as separate phenomena, however, this does not reflect the integrated nature by which racial and emotion socialization processes are interconnected during parents’ and youths’ discussions …

Using Habituation And Affective Forecasting To Distinguish When The Passive Enjoyment Of Harm Begets The Active Pursuit Of Aggression, Drew M. Parton

Theses and Dissertations

Understanding the antecedents and impellers of aggression is key to preventing violence, and individual differences have been identified as some of the key factors of interest in the study of aggression. Antisocial personality traits such as psychopathy, Machiavellianism, Narcissism, and Sadism have received considerable focus from researchers. Among these traits, Sadism stands above them all as arguably the most malevolent of all trait constructs in psychology. Sadism shows the strongest correlations with aggression among malevolent traits and is uniquely linked to unprovoked aggression, even when it is costly. Sadism thus represents an extreme risk factor for aggression, and studying its …

Is Sex Necessary? Or Why You Feel The Way You Do, James Thurber, E. B. White

Zea E-Books Collection

Contents: The Nature of the American Male : A Study of Pedestalism • How to Tell Love From Passion • A Discussion of Feminine Types • The Sexual Revolution : Being a Rather Complete Survey of the Entire Sexual Scene • The Lilies-and-Bluebird Delusion • What Should Children Tell Parents? • Claustrophobia, or What Every Young Wife Should Know • Frigidity in Men • Answers to Hard Questions • Glossary

The year was 1929, the height of the Roaring Twenties and the eve of the Crash and Great Depression. A “Sexual Revolution” was in progress, and two writers from The …

Major Adverse Cardiovascular Events Are Less Frequent In Psoriasis Patients Starting Glp-1ra Compared To Controls: An Observable Retrospective Cohort Study, Ana Ormaza Vera, Marla F. Osorlo, Madison Olexson, June Choi, Chunghwan Ro, Clinton Enos

Department Dermatology Faculty Publications

Background: Psoriasis is an independent risk factor for major adverse cardiovascular events (MACE). We have previously shown that psoriasis patients with dyslipidemia have an increased incidence of MACE despite treatment with a biologic and a statin. Glucagon-like peptide-1 receptor agonists (GLP-1RA) have shown to reduce MACE in patients with type 2 diabetes and obesity, comorbidities that commonly co-occur with psoriasis. However, the association between GLP-1RA and the incidence of MACE among patients with psoriasis remains unknown.

Methods: We conducted a retrospective cohort study from 2014-2024 using a large, multi-center, electronic health record network (TriNetX). Patients aged 18-90 who started GLP-1RA …

Irritable Bowel Syndrome Risk In Acne Patients: Implications For Dermatologic Care, Alex Y. Liu, Ana Ormaza Vera, Clinton W. Enos

Department Dermatology Faculty Publications

[Practice points]

• Clinicians should consider monitoring for early signs of irritable bowel syndrome (IBS) in adult patients with acne to facilitate prompt diagnosis and intervention.
• Clinicians should remain judicious when prescribing antibiotics for acne management to minimize potential disruptions to the gut microbiota and the risk for IBS.
• Isotretinoin may serve as a safer alternative to antibiotics in patients with acne, particularly those with gastrointestinal concerns.

Scopolamine-Induced Modulation Of Serotonin And Dopamine Transporters Activity: Behavioral And Molecular Insights Into Rapid Antidepressant Action, Deepak Karunakaran

Theses and Dissertations

Major depressive disorder (MDD) affects over 350 million individuals worldwide and is characterized by profound dysregulation of serotonin (5-HT) and dopamine (DA) systems that govern mood, reward processing, and motivation. The serotonin transporter (SERT) and dopamine transporter (DAT), both dynamically regulated through phosphorylation, serve as critical determinants of synaptic monoamine signaling. Despite decades of therapeutic development, current antidepressants require 4-6 weeks to achieve efficacy, and approximately one-third to half of patients develop treatment-resistant depression. The emergence of rapid-acting antidepressants like ketamine represents a paradigmatic shift, demonstrating symptom relief within hours; however, ketamine's therapeutic potential remains constrained by abuse liability, dissociative …

Therapy-Induced Senescence In Cancer: Developing Senolytic-Based Combination Strategies To Delay Re-Emergence Of Triple-Negative Breast Cancer, Eesha Chakraborty

Theses and Dissertations

Therapy-induce senescence (TIS) represents a major biological outcome of many anticancer treatments and is increasingly recognized as a strategic vulnerability in triple negative breast cancer, which is a highly aggressive subtype with limited therapeutic options and frequent relapse. Here, we probed TIS as a primary cellular response that may ultimately compromise long-term outcomes using standard chemotherapeutic agents in TNBC as well as the antibody-drug conjugate sacituzumab govitecan (SG). Both chemotherapy and SG reliably induced pronounced senescence across TNBC models, yielding durable growth arrest, however, also generating a persistent reservoir of viable tumor cells capable of eventual proliferative recovery, a hallmark …

Linking Disturbance & Macrophyte Colonization–Extinction Dynamics To Invasion Success & Community Assembly: Integrating Population, Community, & Landscape Perspectives, Joshua T. Armstrong

Theses and Dissertations

Aquatic plants, macrophytes, are foundational components of freshwater ecosystems, influencing abiotic conditions, providing habitat structure, and shaping biodiversity and community assembly processes. Their role is particularly critical in dynamic systems where disturbance regimes and colonization processes interact to shape community patterns and species distributions. Despite their ecological importance, macrophytes remain underrepresented in theoretical and applied studies of metacommunity dynamics and invasion ecology, especially in natural systems experiencing frequent environmental fluctuations. Here we aim to elucidate how macrophytes influence and respond to spatial and temporal variation in aquatic ecosystems, with a particular focus on colonization-extinction dynamics, invasion success, and community assembly. …

Place, Culture, And Care: A Socioecological Examination Of Type 2 Diabetes Among Hispanics In The U.S., Danielle Montoya

Theses and Dissertations

Introduction: Type 2 diabetes (T2D) disproportionately affects U.S. Hispanic populations. This dissertation examined whether structural determinants fundamentally drive T2D disparities among Hispanics, with attention to within-group racial heterogeneity.

Methods: Three studies utilized nationally representative data. Study 1 examined neighborhood segregation and ethnic enclave residence associations with T2D using restricted NHANES data (2011-2018, n=5,056). Study 2 investigated acculturation and T2D associations using restricted NHANES data (2011-2018, n=4,540). Study 3 analyzed patient-provider racial/ethnic concordance and adequate diabetes care using MEPS data (2008-2021, n=17,138).

Results: Structural factors demonstrated primacy across all studies. Neighborhood segregation (aOR=1.17, p>0.05) and ethnic enclave residence showed no …

Exploring The Role Of Host Immune Responses And Bacterial Sensory Pathways In The Development Of Treponema Denticola-Mediated Periodontal Disease, Annie N. Hinson

Theses and Dissertations

Periodontitis is a chronic inflammatory disease driven by dysbiotic microbial communities and maladaptive host responses. Treponema denticola, a spirochete pathobiont, is strongly associated with disease severity. However, the molecular mechanisms underlying its interaction with host tissues and regulation of virulence remain incompletely understood. This work examines both the epithelial immune responses and bacterial transduction systems that shape T. denticola pathogenesis. Transcriptomic analysis of gingival keratinocytes revealed IL-36γ as the most highly induced cytokine following infection with T. denticola. Functional studies demonstrated that IL-36γ induction occurs in a dose- and time-dependent manner through TLR2/6 signaling, requiring the NF-κB, PI3K/Akt, and …

Relationship Extraction Using Retrieval Augmented Generation For Biomedical Dataset, Jannat .

Theses and Dissertations

With the increasing number of structured and unstructured data, obtaining reliable information effectively has become crucial. In the biomedical domain, extracting information from the scientific papers is crucial in order to stay up-to-date with accurate information, given the increased pace by which new research studies are published. This work focuses on identifying relationships between entities that are extracted from the abstracts and titles of biomedical research papers. In this work, we developed a Retrieval Augmented Generation (RAG) based system to automatically identify relations between biomedical entities. We evaluate multiple open source Large Language Models (LLMs) and the number of examples …

Characterization Of Outer Surface Protein C Of Borreliella Role In Host Tropism, Kathryn Mf Chambers

Theses and Dissertations

The Lyme disease spirochetes, Borreliella spp., are maintained in nature through a complex enzootic cycle involving Ixodes ticks and a diverse set of reservoir hosts. The outer surface protein C (OspC) of the bacterium is an essential virulence factor required for transmission from ticks and early infection of mammals. Deletion of ospC abolishes infectivity, yet the precise molecular mechanisms underlying OspC function remain incompletely defined. In this dissertation, I examined the contribution of OspC type identity to host specificity. OspC is highly diverse, with over 30 genetically stable types described. While intra-type sequences are conserved (>95% amino acid …