Digital Commons Network^™

Isolation, Chemical Characterization, And In-Vitro Cytotoxic Evaluation Of Novel Polar Flavonoids From Chromolaena Leivensis, Matthew Tohatsu Tetteh

Electronic Theses and Dissertations

This study focuses on isolation, chemical characterization, and in-vitro cytotoxic evaluation of novel polar flavonoids from chromolaena leivensis. A 95% ethanolic extract of c. leivensis shipped by Prof. Ruben Torrenegra from University of Applied and Environmental Sciences, Bogota, Colombia, was dissolved in 1:1 methanol/chloroform mixture and its purity analyzed by TLC. The sample was eluted with toluene/methanol in an increasing order of polarity on silica gel, resulting in 49 fractions labelled CLA1 to CLA49. Among these fractions, CLA10 (1) and CLA19 (2) obtained yellow and white crystals. They were analyzed by GCMS, IR, and …

Grokking Applied To Chaotic Iterates Of The Logistic Map, Felix Donkoh

Electronic Theses and Dissertations

This thesis investigates grokking, the delayed transition from memorization to generalization in neural networks trained on deterministic chaotic data. Using an integer–arithmetic discretization of the logistic map, yn+1 =( a yn(p − yn))/ p 2 , bounded aperiodic sequences were generated across control parameters α ranging from 3.0 to 4.0. Transformer-based models displayed characteristic grokking curves. In periodic and chaotic regimes, validation accuracy rose suddenly after long plateaus, while at the Feigenbaum boundary (α ≈ 3.57) generalization failed completely. Increasing data diversity restored learning in chaotic domains, and explicit α–conditioning enabled a single network to generalize across all regimes. A …

An Income Subsystem As A Discrete Stochastic Leslie System: A Simulation-Based Approach, Fahd Nii Okantah Cobblah

Electronic Theses and Dissertations

This thesis formulates the household-income engine of an integrated population sim- ulator as a Discrete Stochastic Leslie System (DSLS). The nonnegative state vector nt ∈ Rk + aggregates income, savings, debt, employment, and transfers. (Here, the subscript + denotes the positive cone, i.e., vectors with nonnegative components). Annual evolution is linear in state, stochastic in coefficients: nt+1 = Ttnt + εt, with Tt : Rk + → Rk + cone-preserving. Exogenous macro drivers (inflation, employment, tax, salary inflation, mortgage) are forecast via ARIMA; forecasts multiply entries of Tt, preserving linearity in expectation while introducing realistic temporal correlation. The discrete-event implemented …

Reservoir Characterization Of The Clarksville Formation In Red River County, Texas, Matthew Allen Parker

Electronic Theses and Dissertations

The Upper Jurassic Clarksville Formation in northern Texas and southern Oklahoma is a productive but poorly understood sandstone–conglomerate unit with unresolved questions regarding its depositional environment and sediment provenance. This study evaluates the depositional setting, spatial distribution, and diagenetic controls of the Clarksville Formation using integrated core and well log analyses in Red River County, Texas. Three cores (Lennox Unit #1, Reeder Oil Unit #2, and Reeder Oil Unit #7) were analyzed for lithology, mineralogy, porosity, permeability, and fluid saturation, and correlated with 137 well logs to map formation thickness and regional trends.

Four lithofacies were identified based on core …

World On Fire: The Hunger Games And The Rhetoric Of Revolution, Rachel Olivares

Electronic Theses and Dissertations

In the decade between 2010 and 2020, more people participated in mass protests than at any other point in human history. From the Arab Spring to Occupy Wall Street and Hong Kong’s “umbrella movement,” street demonstrations exploded on a global scale. This period of global unrest coincided with another explosion: the dystopian young adult series The Hunger Games surged in popularity, quickly becoming a cultural phenomenon. Following the release of the book series and its subsequent film adaptations, The Hunger Games became a global symbol of grassroots resistance as social and political movements adopted the language and symbols of its …

Spectroscopic Studies Of Metal Containing Molecules Under Jet-Cooled Conditions Using Laster-Induced Fluoresence (Lif) And Dispersed Fluorescence (Df) Techniques., Md Touhidul Islam

Electronic Theses and Dissertations

This dissertation examines the jet-cooled spectroscopy of the calcium propoxide radical (CaOC₃H₇) to understand how increasing molecular complexity reshapes symmetry, electronic degeneracy, and vibronic coupling. Moving from Ca–OCH₃ to Ca–OC₃H₇ lowers symmetry (C₃v → Cs → C₁) and exposes effects such as spin–orbit splitting and both Jahn–Teller and pseudo–Jahn–Teller distortions. These features remodel the excited-state potential surfaces and are directly observable with laser-induced fluorescence (LIF) and dispersed fluorescence (DF). A central goal is to evaluate whether CaOC₃H₇ supports the near-diagonal vibronic branching needed for efficient optical cycling, while also highlighting implications for catalysis and astrochemistry, where precise spectral fingerprints guide …

Preparing Confident Elementary Mathematics Teachers: Addressing Anxiety, Building Fluency, And Strengthening Practice., Amber Diamond Pendleton

Electronic Theses and Dissertations

This dissertation, presented in three articles, examines how elementary preservice teachers (PSTs) experience and develop as mathematics learners and future educators when methods coursework deliberately integrates mathematical reasoning with affective supports. Collectively, the studies investigate how research-informed instructional design may help address mathematics anxiety (MA), mathematics teaching anxiety (MTA), procedural fluency, and instructional practice. The first article, written for practitioners and elementary mathematics teachers, illustrates how well-established instructional routines, such as number talks and student work analysis, can be facilitated to support procedural fluency in multiplication. Using classroom vignettes, this article highlights instructional moves that make structure visible, promote strategy …

Exposure To Pm2.5 And Aging., Daniel Chris Gomes

Electronic Theses and Dissertations

Inhalation of fine airborne particulate matter (PM_2.5) is an environmental risk factor for numerous health disorders, including cardiovascular diseases (CVD). While several studies have shown that PM_2.5 exposure can induce oxidative stress, DNA damage, and inflammation, the underlying mechanisms that translate these effects into systemic pathology remain poorly understood. Some recent studies have shown that PM_2.5 exposure can lead to telomere shortening in leukocytes, but the generality of this outcome and contribution to endothelial dysfunction has not yet been fully explored. We hypothesized that PM_2.5inhalation accelerates cellular aging and senescence in both circulating peripheral …

Controlling Selectivity In Electrocatalytic Co2 Reduction With An External Magnetic Field., Nawaraj Karki

Electronic Theses and Dissertations

My dissertation describes how to alter the speciation and concentration of molecules at the electrode-electrolyte interface, and how those alterations affect reactivity and selectivity. This dissertation presents two distinct approaches to control the mass transport of neutral molecules such as carbon dioxide (CO₂) at the electrode-electrolyte interface by using an external magnetic field. The first finding demonstrates that magnetic fields indirectly affect the mass transport of target analytes such as CO₂ molecules by selectively interacting with charged species, such as hydroxide ions (OH^-). Such interaction induces magnetohydrodynamic (MHD) effects, which generate localized hydrodynamic flow and …

Symmetry, Stability, And Robust Optimization Strategies For Nonorthogonal Multiconfiguration Self-Consistent Field Wavefunctions., Zihui Song

Electronic Theses and Dissertations

The "different orbital different configuration" (DODC) framework is a general formulation of multireference wavefunctions that allows each configuration (determinant) to possess its own set of optimized molecular orbitals, rather than sharing a common orbital basis as in conventional orthogonal configuration interaction (CI) or Complete Active Space Self-Consistent Field (CASSCF) methods. One prominent example of the DODC framework is the Nonorthogonal Configuration Interaction (NOCI) method, which relaxes the orthogonality constraint between the orbitals of different configurations. This relaxation enables a compact yet flexible description of systems exhibiting strong correlation. By employing multiple nonorthogonal reference determinants, NOCI naturally incorporates orbital relaxation and …

Characterizing Hexavalent Chromium Neurotoxicity Across Laboratory Models., Samuel Thomas Vielee

Electronic Theses and Dissertations

Hexavalent chromium [Cr(VI)] is a ubiquitous environmental pollutant and potent toxicant. Exposure to Cr(VI) in drinking water is primarily associated with cancers, inflammation, and hepatotoxicity; however, recent studies have identified Cr(VI) as a neurotoxicant in rodent and cell culture models. The literature suggest chromium accumulates in the brain, induces widespread neurodegeneration, and alters rodent behaviors. Despite these data, we lack a detailed and consistent assessments of Cr(VI) neurotoxicity across models, and interactions between aging and Cr(VI) neurotoxicity are not reported in the literature. In this dissertation, we characterize Cr(VI) neurotoxicity across 3 laboratory models: Sprague-Dawley rats, Caenorhabditis elegans, and …

The Ecology Of Arthropod Rain In A Tropical Forest., Andrew Robert Seiler

Electronic Theses and Dissertations

Tropical forests are structured by complex vertical linkages and nutrient exchanges between canopy and understory habitats. These linkages include the downward flux of organisms, the movement of canopy fauna, and the recycling of nutrients through litter and organic matter deposition. This dissertation investigates arthropod rain and its role in connecting the canopy and forest floor processes in a lowland tropical forest in Panama. Chapter 2 quantifies “arthropod rain”, the fall of canopy arthropods into the understory. Using pan and pole traps, I measured the composition, abundance, and biomass of arthropods falling from the canopy and assessed environmental drivers of the …

Understanding Social And Cognitive Influences In Medical Students' Learning Processes For Step 1: An Interpretivist Case Study., Ashley Elaine Triplett

Electronic Theses and Dissertations

This qualitative interpretivist case study explores, at a singular institution, medical students’ perspectives on the social and cognitive factors influencing the learning process as students prepare for the Step 1 examination. While prior research regarding medical students Step 1 preparation have focused primarily on wellness, stress, and career outcomes, limited studies have examined medical students' lived experiences to navigate what occurs during the learning process while they prepare for this critical exam. Utilizing a qualitative case study approach, this dissertation draws on fourteen student interviews, seven that passed Step 1 on their first attempt, and seven that failed. Findings reveal …

Safety Evaluation Of Epicertin, An Oral Biotherapeutic Candidate For Treating Ulcerative Colitis: A 28-Day Repeated Dose Toxicity Study., Jimmy Fernando Cifuentes Jimenez

Electronic Theses and Dissertations

Ulcerative colitis (UC) is an inflammatory bowel disease characterized by chronic, relapsing inflammation of the colon and rectum with limited treatment options. Among them, immunosuppressive agents have a high rate of adverse side effects and do not cure the disease. EPICERTIN (EPT), a recombinant variant of the cholera toxin B subunit (CTB) with a C-terminal hexapeptide extension consisting of a KDEL endoplasmic reticulum (ER) retention motif, is a promising oral biotherapeutic candidate for the treatment of UC. EPT has demonstrated mucosal healing activity in mouse models of colitis and human colonic explants. EPT's mechanism of action involves binding to GM1 …

Congolese Mothers' Beliefs That Influence Health-Seeking Behaviors For Their Infants., Shawn Meiman

Electronic Theses and Dissertations

In 2024, approximately 100,000 refugees were admitted to the United States, with 20% coming from the DRC, while Kentucky continues to rank fourth in the country for refugee resettlement. The increasing number of Congolese refugee children in the United States and Kentucky necessitates a greater understanding of these beliefs and practices to ensure equitable, quality, and culturally informed health services. The purpose of this study was to explore Congolese refugee mothers’ culturally and socially situated beliefs, perceptions, practices, and resources related to health care that may influence their views and practices of preventive well-child health care for their infants in …

Scalable Carbon-Based Electrodes For Hole-Transport Layer-Free Perovskite Solar Cells., Sharmin Akter

Electronic Theses and Dissertations

Perovskite solar cells (PSCs) have rapidly reached certified single-junction efficiencies near 26%, but deployment is still limited by operational instability, scale-up challenges, and the cost and complexity of typical device stacks. This dissertation explores a simpler, scalable approach: HTL-free PSCs using low-cost, chemically robust carbon (e.g., carbon black) counter electrodes compatible with low-temperature, solution processing. This work demonstrates how carbon-ink formulation, scalable deposition (blade vs. slot-die), and work-function-tuning additives control film quality, interfacial energetics, and device performance. Carbon inks were developed for both coating methods by systematically varying carbon-to-binder ratio, polymer chemistry, and solvent system. Among the binders screened, ethyl …

“Starlight Suite”: A Compositional Exploration Of The Argo Navis Constellations In Three Movements, Adam Miller

Electronic Theses and Dissertations

This thesis explores a compositional technique in which stellar constellations are arranged upon musical staves in a variety of iterations to create a basis from which to draw melodic, harmonic, and rhythmic material. These raw extrapolations of unaltered notes are then arranged and orchestrated into thematic music for full orchestra, centered around elements from the mythological background behind the constellations used. An accompanying analysis explains the specific applications of this technique within each movement of the work, the significance of each, and the variety of ways in which musical inspiration was drawn from the raw materials. The objective of this …

Discovering Eternal Sunshine: Storytelling Functions Of Vocal Timbre And Layering In Ariana Grande’S 2024 Album, Emily Mcquaid

Electronic Theses and Dissertations

This thesis analyzes the narrative of Ariana Grande’s 2024 concept album eternal sunshine in relation to the 2004 film Eternal Sunshine of the Spotless Mind. Chapter 1 contextualizes the album and its related media, including music videos, additional album releases, a short film, and interviews with insights from Grande. Chapter 2 realizes Peaches as the narrator of the album, demonstrates how the lyrics of each track of the album connect to the film Eternal Sunshine of the Spotless Mind, and establishes the framework for vocal timbre analysis in the rest of the paper. Chapters 3 through 5 analyze how …

Avaren-Fc's Effects On Lymphoma Cells., Jacob Hahn

Electronic Theses and Dissertations

This thesis investigates the therapeutic potential of Avaren-Fc (AvFc), a novel lectin fusion protein that integrates the Fc region of human IgG1 with the engineered lectin Avaren, specifically targeting lymphoma. The study delineates the in vitro binding capabilities of Avaren-Fc with a human B-cell lymphoma cell line, a canine B-cell lymphoma cell line, healthy canine peripheral blood mononuclear cells (PBMCs), and healthy human PBMCs. AvFc was shown to exhibit significant binding to human lymphoma cells. Furthermore, the direct cytotoxicity of Avaren-Fc against canine lymphoma cells, canine lymphoma cells and healthy canine PBMCs was assessed. It was found that there is …

“The Moment You Are Disabled; You Are Cut Off From Society.” Assessing The Experiences Of Disabled Ghanaians And The Rights Enshrined In The United Nations Convention On The Rights Of Persons With Disabilities (Crpd)., Solomon Sackey Amoatey

Electronic Theses and Dissertations

As Ghana continues to pursue inclusion and equality for disabled citizens, considerable tension remains between international human rights frameworks and local social, legal, and cultural practices. Guided by social constructionism and Critical Disability Theory (CDT), this qualitative, chapter-based study examined how disability is constructed through law, policy, and culture in Ghana. It also explored how these constructions influence the interpretation and implementation of disability rights. To achieve this, the study employed semi-structured interviews and document analysis to examine how law, policy, and cultural beliefs intersect to influence the implementation of the CRPD and lived experience of disabled Ghanaians.

Findings show …

Experiences Of Title Ix Hearing Panel Members., Amanda Gage Stonecipher

Electronic Theses and Dissertations

The number of allegations of sexual misconduct on college campuses has been increasing over the past decade and higher education institutions are charged with addressing the misconduct. Addressing student behavior on college campuses through a conduct process is woven into the fabric of higher education, and many institutions use a hearing panel model to determine if institutional policies were violated. My research aims to explore how student conduct hearing panel members process the tension between the emotional management required when hearing intimate and traumatic details of a sexual misconduct case. The data for this research were collected via semi structured …

Impacts Of Biology Modeling Pedagogy On Student Cogitive And Non-Cognitive Elements Of Learning., Jessie K. Newhouse

Electronic Theses and Dissertations

This dissertation employed a quasi-experimental design used to investigate the use of a modeling pedagogy in high school biology. Modeling is a key element of the Science and Engineering Practices of the Next Generation Science Standards. While research of Model Based Pedagogy (MBP) in physics and chemistry is well established, the influence on biology instruction remains less understood. This research examined how MBP affected both cognitive and non-cognitive components of student learning compared to traditional biology instruction. Existing data collected by Dr. Kathy Malone in collaboration with Ohio State University (2016) were analyzed to study the effectiveness of the MBP. …

Optical, Mechanical, And Transport Characterization Of Two-Dimensional Magnetic Materials., Hiruni Weerahennedige

Electronic Theses and Dissertations

This work investigates the structural, magnetic, thermoelectric, and optoelectronic behavior of layered two-dimensional (2D) materials, with emphasis on Fe₃GeTe₂, Ni-substituted Fe₃GeTe₂ alloys, and GeSe. The study aims to clarify how dimensionality, alloying, and external perturbations influence charge transport, magnetic ordering, and light-matter interactions in van der Waals crystals. Single crystals of Fe₃GeTe₂ and (Ni_xFe_1-x)₃GeTe₂ (x = 0-1) were synthesized by chemical vapor transport and characterized using X-ray diffraction, Raman spectroscopy, and transmission electron microscopy. Angle-resolved polarized Raman spectroscopy resolved symmetry-dependent phonon modes and …

Direct And Satellite-Based Quantification Of Greenhouse Gas Fluxes In Small Ponds., Mark Christopher Tierney

Electronic Theses and Dissertations

As evidenced by their historic losses due to anthropogenic activities, wetlands are undervalued ecosystems that provide numerous ecosystem services, from recreational opportunities to carbon (C) storage. However, these wetlands are also the largest natural source of atmospheric methane (CH₄). Additionally, small water bodies (< 10,000 m²) are disproportionately large emitters relative to larger lakes and reservoirs. As construction and restoration efforts proceed, it is crucial to identify wetlands that need restoration and to understand the factors driving both greenhouse gas (GHG) fluxes and the C balance of these systems. This dissertation investigates the drivers of greenhouse gas fluxes …

Plasma-Enhanced Carbon Nanomaterial Synthesis: A Pathway To Reducing Greenhouse Gasses And Carbon-Based Waste., Zane Ronau

Electronic Theses and Dissertations

This research leveraged incorporation of capacitively coupled radio frequency plasma into chemical vapor deposition (CVD) for a reduction in the temperature requirements [a reduction of energy barrier] needed for the conversion of methane (CH₄), carbon dioxide (CO₂), and various carbon-based-waste to produce value-added carbon nanomaterials. An array of catalysts and catalyst supports were employed to optimize the synthesis of graphitic carbon under various gas environments, temperatures and pressures. The nanomaterials synthesized after fine tuning the growth parameters included graphene, carbon nanotubes (CNT), carbon microtubes and carbon nanocages with a variety of properties. Raman Spectroscopy was used …

Synthesis, Characterization, And Chemical Reactivity Of Calcium-Alginate Hydrogel Beads Containing Metal Nanoparticles And Nanoclusters., Rajiv Kumar Singh

Electronic Theses and Dissertations

This dissertation explores the synthesis, stability, and reactivity of various metal nanoparticles (NPs) and nanoclusters (NCs) of varied size and stabilizers contained within millimeter-sized calcium alginate (Ca-Alg) hydrogel polymer beads. Hydrogel beads synthesized by combining sodium alginate with Au or Ag NPs stabilized with trisodium citrate (Cit) and adding dropwise into a 4.0 M Ca²⁺ solution remained stable and contained within the beads. Those synthesized Au, Pd and AuPd NCs stabilized with glutathione (SG) became partially released from the hydrogel within a day. The synthesis of beads containing aggregated Cit Au NPs occurs by inducing aggregation with tetrakis(hydroxymethyl) phosphonium …

Building Bridges: An Appreciative Inquiry Approach To The Development Of Professional Learning To Enhance Teacher–Student Relationships For Students With Emotional Behavioral Disorders., Renee Renz

Electronic Theses and Dissertations

Positive teacher-student relationships are essential to student success yet are often difficult to create and maintain with students identified with Emotional Behavioral Disorders (EBD). Students with EBD frequently struggle with emotional regulation and disruptive behaviors, making relationships and trust both essential and challenging. This study addressed the need for professional learning that equipped educators with strategies to build and maintain positive relationships with students with EBD in secondary school settings. Guided by a participatory action research design, this study used Appreciative Inquiry as a framework for engaging expert secondary teachers from Kentucky in co-constructing professional learning. Appreciative Inquiry focused on …

Artificial Intelligence For Cancer Imaging: Integrated Frameworks For Hepatocellular Carcinoma And Pulmonary Nodules., Ahmed Muhammed Sherif Mostafa Alksas

Electronic Theses and Dissertations

Reliable, reproducible, and clinically useful artificial intelligence (AI) for oncologic imaging requires more than high headline metrics: it demands principled pipelines, calibrated predictions, and designs that generalize across anatomy, scanners, and institutions. This dissertation develops such pipelines in two complementary domains— hepatocellular carcinoma (HCC) on multiphase CT/MRI and indeterminate pulmonary nodules on thin-slice CT—while articulating evaluation and reporting practices that support credible clinical translation. The work proceeds in six core chapters. Two focused reviews synthesize the state of the art in (i) radiomics/AI for HCC and (ii) early assessment of lung nodules, mapping common pitfalls (data leakage, class imbalance, kernel …

Molecular Dynamics Simulations Of Biologically Relevant Interfaces: From Tear Film Lipid Layers To Rna Adsorption On Silica Surfaces., Mahbuba Khanom

Electronic Theses and Dissertations

Molecular dynamics (MD) simulation is an important tool in biochemical sciences for studying complex molecular processes and interfacial interactions at the molecular level. Biological interfaces play key roles in processes such as ocular lubrication and biomolecular adsorption. This dissertation studies interfacial phenomena involving two distinct yet conceptually related systems: the tear film lipid layer (TFLL) at the air–water interface at the surface of the human eye, and RNA adsorption on silica surfaces. These studies provide insight into how interfacial composition, structure, and environmental conditions affect larger-scale behavior. Atomistic MD simulations were used to model the TFLL. The TFLL is essential …

Be Yourself: Life History Of Gay K-12 Educators In Kentucky And Their Lived Experiences., Kevin L. Garner

Electronic Theses and Dissertations

This qualitative life history study explored the lived experiences of gay male educators navigating authenticity, visibility, and advocacy in K–12 schools across Kentucky. Using Queer Theory as the primary framework, complemented by Queer Pedagogy, Culturally Relevant Pedagogy, and Minority Stress Theory, the research examines how social, institutional, and political contexts shape the professional lives and identity expression of gay men working in educational settings. Semi-structured, in-depth interviews were conducted with ten participants, each sharing life narratives that illuminated the intersection between personal authenticity and professional identity within politically and religiously conservative environments. Through reductive analysis and thematic …