Digital Commons Network^™

Development And Evaluation Of A Modeling Platform For Evaluating Immunotherapeutic Efficacy In The Tumor Microenvironment., Dylan Andrew Goodin

Electronic Theses and Dissertations

The tumor microenvironment (TME) represents the complex outcome of numerous tumor, stromal, and immune interactions, and whose composition can significantly affect treatment response. Particularly, immunotherapeutic efficacy is subject to multiple tumor-specific TME interactions that may be difficult to evaluate/predict clinically. Mathematical modelling has been formulated to evaluate specific aspects of the TME, including vasculature, ECM deposition, and immune-tumor interactions. However, the computational challenge of simulating multiple TME interactions has led to sacrificing varying degrees of model generalizability and clinical relevance. This work describes increased computational performance of a 3D continuum model that simulates tumor tissue, ECM, and vasculature using a …

Strategy-Proof Social Choice Functions On Condorcet Domains., Flannery Marie Musk Wells

Electronic Theses and Dissertations

A social choice function is said to be strategy-proof if no voter has any motivation to lie about their true preference. Strategy-proofness is a desirable property of social choice functions so we consider here functions that always satisfy this property. We add to this property the additional desirable conditions of anonymity and neutrality and present domains on which we can get a characterization of majority rule as the only social choice function that satisfies these three properties. Furthermore, we consider what functions look like when we drop the condition of anonymity.

Sustainable Methodologies For Synthesis Of Small Organic Molecules Using Micellar Catalysis., Deborah Sam Ogulu

Electronic Theses and Dissertations

Organic synthesis is a critical process in the creation of small molecule pharmaceuticals and agrochemicals. However, most methods for synthesizing these small molecules rely on toxic organic solvents as the reaction medium which account for approximately 80% of pharmaceutical waste. Moreover, many catalytic reactions require expensive endangered precious metals like palladium and costly metals. This dissertation presents research that aims to develop sustainable, eco-friendly reaction conditions to address these issues. We developed a ligand-free bimetallic nanocatalyst for the hydrogenation of unsaturated enones. This ligand-free nanocatalyst was prepared from nickel and ppm loading of palladium and was stabilized by harnessing the …

Ligand-Stabilized Sno2 As A High-Performance And Scalable Electron Transport Material For Inverted Perovskite Solar Cells., Sashil Chapagain

Electronic Theses and Dissertations

Over the past decade, perovskite solar cell (PSC) technology has attracted significant attention for its low material costs, simple fabrication processes, and impressive photovoltaic performance, with recent power conversion efficiencies (PCEs) surpassing 26%. This advancement marks PSCs as strong competitors to traditional silicon-based photovoltaics. Despite the high efficiency of PSCs, the path to commercialization is hindered by challenges in stability, scalability, and module efficiency. The stability and scalability of PSCs are primarily dependent on the successive charge transfer layers (CTLs) that are interfaced with the perovskite layer. Among CTLs, metal oxide (MO_x) CTLs are preferred for their cost-effectiveness, …

Evaluating The Effectiveness Of Computer-Based Instruction For Training Pre-Service Teachers In Simultaneous Prompting., Mary P. Elliott

Electronic Theses and Dissertations

There has been a significant increase in the use of distance education (DE) in institutions of higher education (IHEs) that is leading to a shift in pedagogy and practices. In the fall of 2021, approximately 61% of undergraduate students nationally were enrolled in at least one online course. A growing number of teacher preparation programs, including special education programs, are utilizing asynchronous course and program designs to combat the critical shortage of certified teachers, yet little research has examined which asynchronous teaching methods are effective for the development of critical teaching skills such as evidence-based practices. One asynchronous teaching method …

Assessing Sustainability Within The Brewing Industry: A Literature Review And Benchmarking Analysis., Elijah Thomas Miller

Electronic Theses and Dissertations

The goals of this study were twofold: to further examine sustainability within the brewing industry through a literature analysis across four academic journals, and a benchmarking analysis of a Louisville, Kentucky brewery’s resource consumption and emissions production. Publications related to the brewing industry were examined for the presence of sustainability keywords: “efficiency, sustainability, carbon footprint, climate change and greenhouse gas”. Benchmarking examined the local brewery’s primary production facility to determine their performance compared to other surveyed breweries pursuing sustainability across the country. Literature examination found noticeable discrepancies between the appearance of sustainability topics within article abstracts and their discussion within …

Using Dynamic Schemas For Query Optimization Over Json Data., Tomas Felipe Llano-Rios

Electronic Theses and Dissertations

Query optimization in document stores has traditionally relied on rule-based approaches, but recent research advocates for a shift towards cost-based optimization. However, this transition is hindered by the fragmented nature of existing approaches, stemming from the early development stage of cost-based query optimization for document databases. A key challenge lies in the absence of a standardized query language and semantics, exacerbated by the diverse and schema-less nature of JSON document collections. To tackle these challenges, the literature has proposed dynamic schemas, primarily utilized at parsing time. However, these schemas lack a formal foundation that describes meaningful semantics for query optimization. …

Predicting The Effects Of Precipitation On Groundwater Contamination Near Capped And Uncapped Coal Ash Storage Facilities In Louisville, Kentucky., Daryl Jialiang Chen

Electronic Theses and Dissertations

This study examines the impact of rainfall event characteristics and water table elevations on arsenic and boron contamination in groundwater near two coal ash ponds in Louisville, Kentucky. Utilizing data from 2011 to 2019, the research focuses on both capped and uncapped ponds at Mill Creek and Cane Run sites, employing Threshold Analysis, Regularized Discriminant Analysis (RDA) and Random Forest (RF) to assess contamination levels in groundwater. Analysis shows that capped ponds generally exhibit reduced arsenic levels, though variations exist depending on the contaminant and site. Key predictors such as maximum precipitation and river height were identified, highlighting their significant …

Educating For Diversity Through A Global Citizenship Education Framework: A Phenomenological Investigation Of Practice., Andrew Alexander Terry

Electronic Theses and Dissertations

With 7.8 billion people in the world, there is a vast array of races, cultures, and languages creating an incredibly diverse globe. Along with the diverse population, we have a world that is also incredibly interconnected. As businesses begin crisscrossing the globe due to global corporations, and advancements in technology we find it more important than ever before to understand all people groups across the globe. So, what does this mean for education in the United States as we become more interconnected with countries all over? Our students need to be better prepared with global competencies that will allow them …

Cybersecurity Education Praxis And Broadening Participation In Cybersecurity: Pieces Of The Same Puzzle., Cynthia N. Thomas

Electronic Theses and Dissertations

This dissertation study examined cybersecurity education praxis and broadening participation in cybersecurity in response to calls of action made by the government-funded National Science Foundation. The cybersecurity education domain has a literature base investigating pedagogical practices that foster cybersecurity learning. However, a gap in the literature is reports of cybersecurity learner perceptions regarding implemented pedagogical practices. Authentic research centering on the experiences of the marginalized and underrepresented identity holders targeted in broadening participation calls is also limited in the cybersecurity education research domain. As such, this study is positioned as a response to the traditionally compartmentalized approaches of praxis and …

Synthesis, Electrical Conductivity, Electrocatalytic Activity For Water Splitting, And Pseudocapacitive Properties Of Perovskite Oxide Derivatives., Kinithi Meththa Kumari Wickramaratne

Electronic Theses and Dissertations

Developing green and sustainable energy solutions is crucial to addressing the energy and environmental challenges. Hydrogen is an attractive candidate given its high energy density and low carbon emission compared to gasoline and coal. Electrochemical water splitting through a water electrolyzer is recognized as a green method for generating hydrogen and oxygen gases. Developing cost-effective electrocatalysts to reduce overpotential in hydrogen and oxygen generation is essential for the overall process. The growing interest in perovskite oxides as versatile and sustainable catalysts is driven by their compositional flexibility, tunable electronic structure, earth abundance, and inherent catalytic performance. In our research, we …

Understanding Land Uses And Their Manifestations Across The Rural-Urban Continua Of Rangpu, Bangladesh And Louisville, Kentucky., Md Jakirul Islam Jony Prothan

Electronic Theses and Dissertations

Rapid urban growth accelerates various features characteristic of rural-urban environments as they change from urban cores to rural areas. This study examines land use change along a rural-urban continuum for two different cities: Louisville, USA, and Rangpur, Bangladesh. Different key land use patterns are compared within and across these different city contexts from 2000 to 2020. Land use change and comparing its spatiotemporal factors are useful metrics to better understand the patterns of development, socio-demographic change, and the uniqueness of cities. Spatial and temporal patterns of sociodemographic and biophysical components of land use provide important information for identifying transition zones …

Electrochemical Modulation Of Surface Plasmon Wave To Investigate Dna-Based Sensing Platforms And Detection Of Sars-Cov2., Anil Sharma

Electronic Theses and Dissertations

This study offers a thorough comparative analysis of optical and electrical signaling strategies for assessing the electrochemical properties of different redox-labeled DNA-based biosensing platforms. In addition, it illustrates the development of an optical interrogation technique with electrochemical modulation of surface plasmon waves (ECM-SPW) as a route for analyzing and implementing DNA-based hybridization sensors. For those quantitative analyses, we chose a model sensing platform composed of a methylene blue (MB)-modified single-stranded DNA (ssDNA) signaling probe and an unlabeled capture ssDNA probe that complements the signaling probe. Two types of signaling probes were employed in this work: one with MB attached to …

Teacher Perceptions Of Principal Impact On School Culture And Teacher Retention In Title 1 Schools., Erika Walker

Electronic Theses and Dissertations

School districts across the United States are grappling to fill, and to keep, their classrooms operating with qualified teachers, especially in Title 1 certified schools. To ensure a quality education for the millions of students in the nation in the coming years, educational leaders and government officials need to evaluate what can be done to increase the number of teachers staying in their positions. Schools must be better equipped to understand teachers’ sense of belonging and teacher retain and how principal impact contributes to high turnover rates. The purpose of this phenomenological qualitative study was to examine teachers’ perception on …

Barocaloric Heat Pumps Based On Soft Materials., Naveen Weerasekera

Electronic Theses and Dissertations

Solid-state refrigeration offers a promising alternative to traditional vapor compression systems that are relatively inefficient, unreliable, and have a high global warming potential. Various solid-state cooling technologies, including those based on electrocaloric, magnetocaloric, and elastocaloric effects have been investigated in the recent past. However, concerns regarding their efficiency, scalability and cost remain. Refrigeration and heat pump technologies based on the barocaloric effect (temperature/entropy change due to hydrostatic pressure) hold great promise but have received comparatively less attention. Barocaloric heating/cooling based on low cost, compressible soft materials with large barocaloric response have the potential to pave the way for efficient, scalable, …

Multimodal Stylometry: A Novel Approach For Authorship Identification., Glory O. Adebayo

Electronic Theses and Dissertations

This dissertation introduces multimodal stylometry, a novel approach to authorship identification that integrates text and source code features for a comprehensive understanding of an author's unique style. Traditional stylometric methods have primarily focused on either text stylometry or source code stylometry, thereby neglecting the potential insights that multimodality may provide. This research aims to bridge this gap by proposing a framework that combines textual and source code data to enhance the accuracy and reliability of authorship identification. The study begins by reviewing existing literature on authorship identification and stylometry, highlighting the limitations of unimodal approaches. Leveraging recent advancements in multimodal …

Utilizing Metal Ligand Cooperativity To Activate Small Molecules., Christine Burgan

Electronic Theses and Dissertations

The problems created from the excessive use of fossil fuels can be approached from two directions: capture the CO₂ from the atmosphere or develop alternative energy sources. The current industrial standards for these are environmental and/or health hazards and utilize precious metals, respectively. Metal ligand cooperativity (MLC) has emerged as a promising alternative to using precious metals to activate small molecules. In this dissertation, we focus on a series of metal complexes based on the ligand diacetyl-2-(4-methyl-thiosemicarbazone)-3-(2-hydrazinopyridine) (H₂L¹) for either hydrogen evolution or CO₂ capture. The novel complexes were characterized by ¹H NMR, …

Multithreaded Applications On The Heterogeneous Research Computing Environment., Sungbo Jung

Electronic Theses and Dissertations

Bioinformatics is a domain that has experienced rapid research growth in recent years, as evidenced by the increasing number of articles in biomedical databases such as PubMed, which adds over a million publications every year. However, this also poses a challenge for researchers who need to find relevant citations for their work. Therefore, developing efficient indexing and searching methods for text data is crucial for Bioinformatics. One key technique for information retrieval is document inversion, which involves creating an inverted index to enable efficient searching through vast collections of text or documents. This Ph.D. research aims to design the research …

Investigations Of Physical Properties Of Novel Magnetic And Non- Magnetic Two-Dimensional (2d) Alloys., Mohammed Ameen Irziqat

Electronic Theses and Dissertations

This research work reports investigations of structural and physical properties of novel magnetic and non-magnetic 2D alloys. Three techniques were utilized in this investigation: Angle-resolved polarized Raman spectroscopy (ARPRS), Electrical &Thermoelectric power measurements, Magneto-optic Kerr effect (MOKE) spectroscopy. ARPRS and MOKE experiments were constructed during the course of this work. ARPRS was used to study the anisotropy of 2-dimensional black-arsenic phosphors (b-AsxP1-x) as a function of arsenic concentration (x). It was observed experimentally that all Raman modes of the studied samples with x=0, 0.4, 0.8 exhibit polarization dependence. More interestingly, the polarization dependence of Raman modes due to the vibrations …

Advancement Of Iterative Optimization Technology Algorithms Toward Calibration-Free Process Analytical Technology Applications, Adam Rish

Electronic Theses and Dissertations

The expansion of spectroscopic process analytical technology (PAT) tools within the pharmaceutical industry has the potential to elevate the current state-of-the-art of pharmaceutical manufacturing by offering opportunities for reduced quality testing times, enhanced process control, and greater production flexibility. Spectroscopic PAT tools are dependent on multivariate models to extract the relevant information from the spectral outputs. However, there is a substantial calibration burden for developing and maintaining these multivariate models that discourages the application of PAT, despite the encouragement from regulators. This has led to an interest in calibration-free methods such as iterative optimization technology (IOT) for spectroscopic PAT that …

Magnetic Properties Of Zgnrs With Nitrogen And Fluorine Adsorbates, A Computational Study, Justin Petit

Electronic Theses and Dissertations

Imposing dimensional restrictions on graphene sheets and adding impurities can give rise to carbon nanostructures with magnetic properties. In this work, zigzag graphene nanoribbons, zGNRs, with nitrogen and fluorine adatoms are investigated for magnetic properties of interest for spin devices. Geometry optimizations were done determining which position along a zGNR electrode that N and F would favorably attach to. Edge positions were determined as the most stable attachment site. M-cell zGNR electrodes (M = 1-3) edge-functionalized by N and F adatoms were investigated with respect to their band structures and spin densities in antiferromagnetic and ferromagnetic, AFM and FM, configurations. …

Coastal-Ocean And Estuarine Acidification In Long Bay, South Carolina: A Comparison Of In-Situ Water Quality Monitoring With Measured Carbonate System Parameters, Mary Olsen

Electronic Theses and Dissertations

One of the major water-quality issues impacting our coast and estuaries is coastal-ocean and estuarine acidification. Due to a relative dearth of data in the southeastern United States it is increasingly difficult to determine the full extent and intensity of this problem. This study provides the first characterization of coastal-ocean and estuarine acidification in Long Bay, SC by attempting to leverage long-term water quality data sets at two coastal-ocean pier sites using in-situ YSI EXO sondes deployed at both the surface and bottom waters along with two estuarine sites sampled by volunteer monitors using Orion star multi-meters. Discrete samples (120) …

Gifted And…: Teacher Reflection And Transformation In Response To Teaching Gifted Students, Patrick Gene Rabon

Electronic Theses and Dissertations

12 teachers, representing five schools in a district, shared via individual interviews their insights regarding giftedness and the needs of gifted students. These interviews explored the characteristics of giftedness and gifted education, the needs participants identified through their experiences with their students, the choices participants made regarding these needs, and the various ways participants reflected on these choices. This study used reflexive thematic analysis and transformative learning theory to make sense of the data, and a reparative approach shaped the study’s approach to the collection and analysis of the data. This study found that participants tended to think in terms …

The Elephant In The Classroom: Understanding Teachers’ Implicit Biases In Grading Student Work In A Mathematics Classroom, Tina Marie Medina

Electronic Theses and Dissertations

This study focused on automaticity or the choices we make without conscious thought. Specifically, the study examined how math teachers improved their understanding of the practice and evolution of culturally responsive teaching by analyzing the lived experiences and metacognition of practicing middle school teachers as they assess student work in mathematics. The potential impact of implicit stereotypes, instructor expectations, assessment design, cultural considerations, and other variables on the grading process was investigated. The purpose of this case study was to uncover teachers’ implicit biases as it relates to grading student work in a middle school math class.

This qualitative study …

Exploring The Mathematics Identities Of Urban Teacher Residents Using A Trauma-Informed Framework., Samantha Morris

Electronic Theses and Dissertations

Urban Teacher Residency (UTR) models prepare teachers to specialize in urban education. All teacher candidates, including those in UTR programs, have experiences and emotions that shape their mathematics identities. These identities can impact both the residents’ mathematics instruction and the experiences of their students. This study examines how residents’ mathematics identities developed as they participated in a Mathematics for Elementary Teachers (MET) course. To support this development, trauma-informed care (TIC) practices were embedded within the course. Such practices were designed to help residents process and heal from any potential mathematics trauma as they prepared to be teachers. This dissertation study …

Smart Manufacturing Of Cement: From Lab-Scale Simulation And Testing To Industry-Scale Deployment., Juan David Tabares Tamayo

Electronic Theses and Dissertations

Cement kilns are controlled by experienced process operators who follow experience-based industry guidelines using data collected and fundamental knowledge. The manufacturing process, which is equipped with sensors and equipment, transfers data/information to the operators to aid standardized decision-making operations. In contrast, companies have used such data to develop and implement digital solutions for predictive control systems; in effect, FLSmidth and Rockwell Automation. However, despite the availability of automated control systems and investigation in automation for process monitoring and optimization, opportunities to radically optimize cement manufacturing are still abundant and in need of implementation. Therefore, this research developed simulation models and …

Phenomenological Study Of The Impact Of Stress And Burnout After Covid-19 On Educators: Supporting Teachers In Resiliency And Facilitating Adversarial Growth Post-Pandemic., Rebecca Hicks-Hawkins

Electronic Theses and Dissertations

COVID-19 has not only caused anxiety and fears among teachers for their own health and that of their families; they are also facing increased responsibility. Planning periods had been replaced with coverage periods, where teachers must teach other classes when their colleagues are out—often due to illness—because the supply of substitute teachers cannot meet the demand (Barton & Dickason, 2022). Teaching is a demanding profession, and there will always be stress associated with a job where so many external factors come into play (Hansen, 2013). However, in the face of adversity some teachers were thriving. They are showing up and …

Development Of A High-Resolution Mid-Infrared Spectroscopy Apparatus For The Study Of Methane And Other Astrochemical Molecules., S M Shah Riyadh

Electronic Theses and Dissertations

This research documents steps towards building a novel spectroscopic technique, namely, cavity-enhanced double-resonance (CEDR) spectroscopy, for investigating methane (CH₄) and other molecules with significance in astrochemistry. These efforts focus on tackling the complexities of their ro-vibrational energy levels and the inefficiencies in analyzing vibrational spectra, particularly for molecules with high symmetry and strong intramolecular interactions. In the CEDR spectroscopy, the first photon, generated by a continuous-wave optical parametric oscillator (CW-OPO) locked to a Doppler-free saturation absorption line, excites the molecule from its ground level to a selected excited ro-vibrational (rotational-vibrational) level, e.g., that of the asymmetric CH-stretch mode. …

A Qualitative Inquiry Into The Intersectionality Of Race, Gender, And Social Networks In Stem Education., La'ree Alexandria Shontee

Electronic Theses and Dissertations

This study explores the intersectional experiences of Black women in Science, Technology, Engineering, and Mathematics (STEM) education by focusing on the strategic utilization of social capital to navigate systemic barriers and challenges. The unique struggles faced by Black women within predominantly white and male-dominated STEM programs are addressed in this study. Drawing on a growing body of literature, this research diverges from prevailing narratives of disinterest in or departure from STEM programs and instead illuminates proactive strategies employed by Black women. Through an exploration of social capital - encompassing networks, resources, and support systems - this study offers a comprehensive …

Synthesis And Characterization Of Indole-Based Zinc Dipyrrin Photosensitizers, Jean-Pierre Sanza

Electronic Theses and Dissertations

Metal complexes of dipyrromethene (dipyrrins) used as sensitizers in photocatalysis offer a way to harness solar energy in chemical bonds to create new fuels. This offers the dual role of reducing fossil fuel dependence and atmospheric CO₂ levels. Traditionally, metal dipyrrin complexes are synthesized using substituted pyrroles, aldehydes, and transition metals. Indoles have a more expanded pi-electron system and their dipyrrin-type complex may exhibit visible light absorption, suggesting that they can act as photosensitizers for CO₂ reduction processes. A novel indoledipyrromethene was synthesized using unsubstituted indole and mesitaldehyde. The complex exhibits visible light absorption at 422 nm. Its …