Digital Commons Network^™

Modeling And Debiasing Feedback Loops In Collaborative Filtering Recommender Systems., Sami Khenissi

Electronic Theses and Dissertations

Artificial Intelligence (AI)-driven recommender systems have been gaining increasing ubiquity and influence in our daily lives, especially during time spent online on the World Wide Web or smart devices. The influence of recommender systems on who and what we can find and discover, our choices, and our behavior, has thus never been more concrete. AI can now predict and anticipate, with varying degrees of accuracy, the news article we will read, the music we will listen to, the movies we will watch, the transactions we will make, the restaurants we will eat in, the online courses we will be interested …

New Debiasing Strategies In Collaborative Filtering Recommender Systems: Modeling User Conformity, Multiple Biases, And Causality., Mariem Boujelbene

Electronic Theses and Dissertations

Recommender Systems are widely used to personalize the user experience in a diverse set of online applications ranging from e-commerce and education to social media and online entertainment. These State of the Art AI systems can suffer from several biases that may occur at different stages of the recommendation life-cycle. For instance, using biased data to train recommendation models may lead to several issues, such as the discrepancy between online and offline evaluation, decreasing the recommendation performance, and hurting the user experience. Bias can occur during the data collection stage where the data inherits the user-item interaction biases, such as …

Protest-Related Tear Gas Exposure And Menstrual Function, Emily Kathleen (Steinmetz) Reece

Electronic Theses and Dissertations

During the racial justice protests of 2020 and 2021, crowd control chemical irritants (referred to as “tear gas”) were deployed against protesters, after which there were anecdotal reports of altered menstrual cycles among exposed individuals. There is only one peer reviewed published study on tear gas exposure and menstrual health. This study examined whether tear gas exposure was associated with menstrual cycle outcomes among women attending the 2020-2021 protests. Data from 103 women who attended racial justice protests in 2020 and 2021 were collected through an online questionnaire. Data included protest attendance, acute symptoms of tear gas exposure, whether medical …

Mission Drift And The Effectiveness Of Resource Dependence Theory In An Internally Resource-Constrained Environment., Kirsten Bullock

Electronic Theses and Dissertations

Why are some organizations able to maintain focus on their mission while others founder? This theoretical and empirical dissertation examines the relationships among funding sources, management practices, and organizational stigma within an internally resource-constrained environment. Using Resource Dependence Theory (RDT) as a basis to manage external resource dependencies, I build a theoretical model and empirically test a research model to understand how funding source affects mission drift, how management practices might help organizations manage that drift, and what effect organizational stigma might have on those relationships within an environment of internal resource constraints. Specifically, this study hypothesizes that nonprofits that …

The Water We Were Swimming In: Transgender And Gender Nonconforming Students' Lived Experiences In Engineering., Natalie Saroff Oliner

Electronic Theses and Dissertations

Few studies address the lived experiences of transgender and gender nonconforming (TGNC) students in engineering. Grounded in critical trans politics (Spade, 2015), this dissertation contributes to the literature on TGNC students in engineering by examining their experiences negotiating their identities while navigating interrelated systems of oppression in a field dominated by White, heterosexual, cisgender men. Using a critical constructivism framework, I conducted a narrative inquiry to explore the lived experiences of five TGNC students in engineering programs. Participants experienced TGNC oppression at their universities, built LGBTQ+ and TGNC communities, and described more welcoming climates in non-engineering contexts compared to engineering. …

The Role Of Accuracy In Children’S Judgments Of Experts’ Knowledge., Allison J. Williams

Electronic Theses and Dissertations

Children prefer to trust people with expertise and people who are accurate. Because experts make mistakes and give incorrect information (e.g., predictions and diagnoses), this dissertation explores children’s judgments of knowledge for experts who provide inaccurate information. Across two studies, 6- to 9-years-olds (N = 160) were introduced to two experts in different domains (doctor and mechanic) and rated how much each expert knows about their relevant domain. Then, over four consecutive trials, participants heard one expert give inaccurate answers to easy questions in their domain. After each trial, children explained why they believed the expert gave inaccurate answers …

Authentically (Un)Real Assessing Vh!'S Basketball Wives And Its Violent & Colorist Portrayals Of Black Women., Wilma Denae Powell

Electronic Theses and Dissertations

Does reality television serve as solely a form of entertainment, or could reality television also be maintaining hegemonic beliefs and reinforcing biased views of Black women? Since 2010, Vh1’s Basketball Wives has given audiences the opportunities to entertain themselves by watching women who are/were married to, dating, or are the mothers of children fathered by professional basketball players. Despite the show’s name, few members of the cast are currently married and audiences only get mere glimpses of the cast in motherly or marital interactions. So, what does Basketball Wives offer audiences who tune in to watch Black women for entertainment? …

Characterization Of Fundamental Parameters That Modulate Acoustofluidic-Mediated Molecular Delivery To Cells., Connor Sterling Centner

Electronic Theses and Dissertations

Cell-based therapies represent the latest biotechnological revolution in medicine, but significant limitations exist in non-viral intracellular delivery techniques during manufacturing of cell therapies. To address these limitations, a novel acoustofluidic device was developed to deliver ultrasound waves into a flow chamber for rapid molecular delivery to human cells. Our acoustofluidic device delivers biomolecules by inducing expansion and collapse of exogenous gas-filled microbubbles (“cavitation”), which enhances molecular delivery to nearby cells. Experimental studies were conducted to characterize key parameters that influence acoustofluidic-mediated molecular delivery to human cells. A clinical ultrasound transducer was generally utilized with varying cationic microbubble concentrations. Intracellular delivery …

Materials And Interfaces For Electrocatalytic Hydrogen Production And Utilization., Alexander Jiya Gupta

Electronic Theses and Dissertations

Mass industrialization over the last few centuries has created a global economy which is dependent upon fossil fuels to satisfy an exponentially increasing demand for energy. Aside from the possible depletion of this finite resource, the combustion of fossil fuels releases greenhouse gases into the atmosphere which cause the global temperature to rise – a phenomenon which has already begun to create geologic and geopolitical instability and shows no signs of abatement. One proposed method to rid humanity of its dependence on fossil fuels is to use green hydrogen as an energy carrier. In this scheme, excess electricity from a …

Transformation., Jingshuo Yang

Electronic Theses and Dissertations

My works mainly show my perception of life and my change of thought. The world is full of changes, and the pandemic has disrupted our lives. Many people, including me, are confused about the world. Philosophy and my observation and thinking about the world helped me to have a clearer understanding of the world. My paintings Licia, Butterfly Woman, and Live with Covid reflect my understanding of German philosopher Arthur Schopenhauer's theory of empathy. Within my art, I also use another German Philosopher Theodor W. Adorno's theory of the culture industry to deepen my understanding of some social phenomena. My …

Beyond Accuracy In Machine Learning., Aneseh Alvanpour

Electronic Theses and Dissertations

Machine Learning (ML) algorithms are widely used in our daily lives. The need to increase the accuracy of ML models has led to building increasingly powerful and complex algorithms known as black-box models which do not provide any explanations about the reasons behind their output. On the other hand, there are white-box ML models which are inherently interpretable while having lower accuracy compared to black-box models. To have a productive and practical algorithmic decision system, precise predictions may not be sufficient. The system may need to have transparency and be able to provide explanations, especially in applications with safety-critical contexts …

Aggregatibacter Actinomycetemcomitans Exploits And Modulates The Immune Response By Human Neutrophils For Survival In The Anaerobic Environment., Hazel Ozuna

Electronic Theses and Dissertations

Aggregatibacter actinomycetemcomitans (Aa) is a Gram-negative facultative anaerobe and an opportunistic oral pathogen, strongly associated with localized periodontitis and other inflammatory diseases. Periodontitis is a chronic inflammation of the periodontium resulting from the inflammatory response of the host towards the dysbiotic microbial community present at the gingival crevice. The host immune response creates a hostile environment for microorganisms; therefore, it is important for Aa to be able to regulate the necessary genes to survive and thrive in such an environment. Aaexpresses several virulence factors such as a cytolethal distending toxin (Cdt), lipopolysaccharide (LPS) and leukotoxin A (LtxA), …

Public Health Contagion Of White Supremacy: Examining The Pipeline Of Attitudes About Racism And Racial History Education Among High School Students., Trinidad Jackson

Electronic Theses and Dissertations

We are living in compounded states of upheaval. Violence and exemption from it across socioecological levels have shaped how humans survive, thrive, and die. While different violence typologies exist, the U.S., prioritizes interpersonal violence as its primary target of intervention, often through structural means that foster and reinforce interpersonal violence. The omission of structural and cultural agents and outcomes of violence allows perpetrators to infiltrate and reproduce savage, dehumanizing ideologies in perpetuity. Instead of sustaining societal pillars that oppress and destroy, we must fertilize public health research, practice, and sociopolitical activism with pillars that both inform and activate liberatory consciousness …

The Role Of Organizational Culture And Relationship Marketing In Disability Sport Sponsorship: An Exemplar Case Study., Nina Siegfried

Electronic Theses and Dissertations

Worldwide, disability sport faces funding challenges. Sponsorship offers a viable alternative to combat the lack of sustainable funding in disability sport. Exploring how organizational culture can be leveraged to increase strategic partnerships, the purposes of this multiple manuscript dissertation were to (a) examine the elements of the organizational culture that make a successful international wheelchair basketball sport club attractive to external partners and (b) determine what role those organizational cultural elements play in leveraging relationship marketing (RM) for sponsorship acquisition and retention. Utilizing an exemplar case study methodology, the focus of this study was the RSV Lahn-Dill, an international wheelchair …

Etracellular Vesicles From Lactobacillus Rhamnosus Gg Protect Against Alcohol-Induced Liver Injury Through Suppression Of Intestinal Mir 194 And Subsequent Activation Of Fxr In Mice., Mengwei Jiang

Electronic Theses and Dissertations

Numerous studies have reported the efficacy of probiotics for alcohol-associated liver disease (ALD). These studies indicate a strong interest among the scientific and medical communities in identifying alternative or adjunctive approaches for ALD, for which there is no effective or widely accepted therapeutic option. However, in-depth molecular knowledge on how probiotics render their effects is lacking. Patients with ALD often have increased hepatic bile acids (BAs), which can be toxic and are an important causative factor in liver injury and hepatocyte death. BAs are released into the intestines and serve not only as a “detergent” to promote fat absorption, but …

Porphyromonas Gingivalis, Ethanol, And Chronic Diseases., Nicholas Alan Short

Electronic Theses and Dissertations

This dissertation is an investigation into the relationships among Porphyromonas gingivalis, ethanol, and a series of chronic diseases, focusing primarily on atherosclerosis. It uses evolutionary theory to understand clinical parameters related to chronic disease biology. The initial research question was, "If people who drink a glass of wine each day have a lower risk for atherosclerosis, could one explanation involve antibacterial effects on pathogens associated with causing atherosclerosis, namely, Porphyromonas gingivalis?". This dissertation is divided into four chapters. Chapter One provides the foundational information pertinent to the dissertation. Chapter Two describes an in- vitro experiment aimed at understanding …

Understanding Public Emergency Preparedness Before And During The Coronavirus Outbreak: Implications For Effective Public Health And Risk Communication., Raphael Adjetey Fumey

Electronic Theses and Dissertations

The COVID-19 pandemic has resulted in a dramatic loss of human lives globally and presents an unprecedented challenge to public health, the world of work, and our food systems. The social and economic disruption caused by the COVID-19 pandemic is devastating, putting several millions of people at risk of falling into extreme poverty, with over 500 million people being undernourished. It is evident from the data on COVID-19 cases, deaths, and hospitalizations that the United States is the worse hit country, which can be attributed to the lack of preparedness at the individual, environmental, and government levels. This study applied …

Structural, Charge Transport, Gas Sensing, Magnetic, Pseudocapacitive, And Electrocatalytic Properties Of Perovskite Oxides., Surendra Bahadur Karki

Electronic Theses and Dissertations

Perovskites are functional materials with the general formula ABO₃ (A = alkali, alkaline earth or lanthanoid cations and B = transition metal or main group cations). These materials are marked by a variety of crystal structures and interesting properties such as colossal magnetoresistance, ferroelectricity, multiferroicity, superconductivity, pseudocapacitance, gas sensing, charge transport, and electrocatalytic properties. The formula of perovskite can be written as AA’BB’O₆, when there is ordering between two cations over A and B-sites. Such compounds are called double perovskite oxides. Some amount of oxygen could be lost from crystal structure without decomposition of the phase. Such …

Particulate Hexavalent Chromium Inhibits Homologous Recombination Repair By Targeting Rad51 Paralogs In Human Lung Fibroblasts., Aggie R. Williams

Electronic Theses and Dissertations

Hexavalent Chromium [Cr(VI)] is a known human lung carcinogen and general health hazard. The mechanism of carcinogenesis remains poorly understood, but chromosome instability (CIN) is the major theory in its carcinogenic mechanism. Homologous recombination (HR) repair is a DNA repair pathway that prevents CIN by repairing DNA double-strand breaks. RAD51, a key mediator protein of HR repair, along with the RAD51 paralogs (RAD51B, C, D, XRCC2, and 3) are required for HR repair. During HR, RAD51 loads and forms a helical nucleoprotein filament structure to promote DNA strand exchange and stimulate pairing activity of DNA. Cr(VI) exposures have been shown …

The Reading Of Sir Toby Belch: A Queer And Black Exploration Of William Shakespeare's Twelfth Night., Jahi E Bogard

Electronic Theses and Dissertations

This MFA thesis explores queer, black representation in William Shakespeare’s drama and in the University of Louisville’s Department of Theatre Arts Fall 2021 production of an adaption of Twelfth Night (1601). Directed by Jennifer Pennington, the repurposed script and non-traditional casting targeted a modern audience. Cast as Olivia’s drunk uncle, Sir Toby Belch, I aimed to discover if my identify as a black, queer, cis man could be incorporated into Shakespeare’s text. Sir Toby Belch’s raucous, heterosexual, and sometimes violent, traits are often imagined today as innately masculine. I argue that Shakespeare’s plays can be appropriated by queer, black actors …

Fabrication And Characterization Of Lactobacillus Crispatus Containing Bioprints For Bacterial Vaginosis Application., Anthony J. Kyser

Electronic Theses and Dissertations

Bacterial vaginosis (BV) is a condition in which healthy lactobacilli are replaced by an overabundance of pathogenic bacteria in the female reproductive tract. Current antibiotic treatments often fail to “cure” infection, resulting in recurrence in more than 50% of women, 6 months post-treatment. Recently, probiotics have demonstrated promise to restore vaginal health; however, as with other active agents, delivery requires once-to-twice daily administration. Recently, three-dimensional (3D)-bioprinting has enabled the fabrication of well-defined cell-laden architectures with tunable agent release, thereby presenting a novel approach with which to deliver probiotics. One promising bioink, gelatin alginate, was selected for study, due to its …

Di•As•Po•Ra: Displaced, Not Erased., Betty Álvarez

Electronic Theses and Dissertations

This thesis is based on my artistic endeavors and research founded in my culture, family, the history of the United States government’s intervention in El Salvador, and the current political climate Latin Americans face today in the United States. I work within multiple mediums to resurrect pieces of my culture that are being forgotten or left behind due to assimilation. I accomplish this through revisiting and reinterpreting traditions. I aim to bring awareness of the Latin experience in a racially divided United States through artistic expression and my own personal experiences. My works are made to feel whimsical and playful, …

Hybrid Machine And Deep Learning-Based Cyberattack Detection And Classification In Smart Grid Networks, Adedayo Aribisala

Electronic Theses and Dissertations

Power grids have rapidly evolved into Smart grids and are heavily dependent on Supervisory Control and Data Acquisition (SCADA) systems for monitoring and control. However, this evolution increases the susceptibility of the remote (VMs, VPNs) and physical interfaces (sensors, PMUs LAN, WAN, sub-stations power lines, and smart meters) to sophisticated cyberattacks. The continuous supply of power is critical to power generation plants, power grids, industrial grids, and nuclear grids; the halt to global power could have a devastating effect on the economy's critical infrastructures and human life.

Machine Learning and Deep Learning-based cyberattack detection modeling have yielded promising results when …

Examining Adolescent Voices In Urban Montessorianism Within The Third Plane Of Development., Raymond Edward Green

Electronic Theses and Dissertations

Although there is a significant body of research surrounding Montessori education, little research has sought to capture the voices of adolescents, specifically high school students in urban settings (Dr. Montessori’s third plane of development) learning through the Montessori Method. Problem: Legislators, policy writers, district and school-level leaders mandate and implement reforms with minimal to no adolescent input. Further, adolescents are not part of the reform implementation process or identifying desired outcomes of said reform initiatives. Purpose: The purpose of this study was to examine adolescent’s perspective of their urban high school Montessori education, and their role in helping to develop …

Adipose-Derived Stromal Vascular Fraction Therapy Improves Age-Related Adrenergic Mediated Microvascular Dysfunction And Increases Revascularization Potential Following Injury., Gabrielle Brown

Electronic Theses and Dissertations

The role of the microcirculation is to balance blood flow and oxygen delivery to meet local metabolic and oxygen demands. With advancing age, the health of the endothelium declines leading to improper augmentation of the microcirculation; decreasing vasoreactivity and angiogenic potential which can further increase the risk of ischemia. The multiple contributing factors that drive the decline in endothelial health with age make traditional pharmacological interventions challenging whereas cell-based therapies can exert multifactorial gains. Adipose-derived stromal vascular fraction (SVF) is an emerging therapeutic for its easily accessible, autologous, anti-inflammatory, and angiogenic properties. It is a heterogenous population comprised of leukocyte …

Lysosomal Evasion Of Legionella Pneumophilia The Effector., Bethany Vaughn

Electronic Theses and Dissertations

Legionella pneumophila is a Gram-negative facultative intracellular bacterium found in freshwater environments that has co-evolved to survive and proliferate in various amoeba and protozoan species, which serve as the natural host for the bacterium. Humans are an accidental host of L. pneumophila, where infection occurs upon inhalation of aerosolized water droplets that contain the bacteria. Intracellular proliferation of L. pneumophila in alveolar macrophages is essential for manifestation of pneumonia, designated as Legionnaires’ Disease. Biogenesis of the legionella containing vacuole (LCV) occurs via interception of ER-Golgi vesicle trafficking and avoids the default endosomal/lysosomal degradation pathway. Intracellular proliferation of L. pneumophila …

“I Think It's Male Privilege”: A Qualitative Study Of Personal, Behavioral, And Socio-Environmental Factors Influencing High Risk Sexual Behavior And Hiv Transmission Among Heterosexual Adult Males In Ghana., Nana Ama Aya Erzuah Bullock

Electronic Theses and Dissertations

There are roughly 340,000 adults and children living with HIV. Despite the progress in the global response and the lowing of infections, HIV rates in Ghana remain stable. Cultural and societal norms that exist at a given time and place influence masculine socialization and behavior. These norms promote heterosexual men’s engagement in high-risk sexual behaviors which result in HIV infections. Factors such as HIV knowledge, risk perception, male condom use, HIV testing, and counseling which minimize the risk of HIV, are also influenced by these norms. Men have been identified as assets and advocates for behavior change and social responsibility …

The Role Of Obesity In Macrophage-Mediated Mechanisms Promoting Early-Onset Colon Cancer., Katharina Marietta Scheurlen

Electronic Theses and Dissertations

Early-onset colon cancer (EOCC) is a leading cause of cancer death among people younger than 50 years of age in the United States and is associated with metabolic dysfunction and obesity. Anti-inflammatory tumor-associated macrophages (TAM) and low Peroxisome Proliferator Activated Receptor Gamma (PPARγ) gene expression in colon cancer (CC) tissue promote tumor progression and decreased patient survival. Obesity-related hormones, such as leptin and adiponectin, have the potential to affect gene expression in TAM to promote CC progression and thereby link obesity and EOCC. The aim of this project was to identify target genes in human CC and to investigate the …

"Death Can't Touch Them Now": Aids Response And Memorialization In Louisville, Kentucky, 1982-1992., Olivia A. Beutel

Electronic Theses and Dissertations

This thesis aims to address the role of the queer community in Louisville, Kentucky during the AIDS epidemic. Beginning with the first reported AIDS death in the city in 1983 throughout the 1980s, dialogue focused on those living with AIDS, specifically on education for prevention and aid to those afflicted by the disease. Individuals in the queer community—gay men, lesbians, bisexual men and women, transgender men and women, and others—created resources that were not being provided by the larger city government. Then, in the 1990s, national attention to the AIDS Memorial Quilt encouraged people to participate in rituals of commemoration, …

Black Ads Matter: An Analysis Of Black Representation In Advertising., Elyssa Quinn Smith

Electronic Theses and Dissertations

During the summer of 2020 Black Lives Matter (BLM) became a rallying cry throughout the United States and the world. At that time, many individuals and organizations reflected on how they could better support the movement for equality, equity, and inclusion, but some of the results were ingenuine, perceived as virtue signaling or woke washing. In this thesis I explore the Black representation in advertising from three prominent car brands from both pre- and post-summer 2020. I analyze ads from Acura, Buick, and Lincoln to determine if they are synergistic and include multi-dimensional Black representation, criteria Burgess et al.’s (2020) …