Digital Commons Network^™

Modeling Vaccination Strategies And Intervention Impacts On Infectious Disease Dynamics, Elizabeth B. Amona

Theses and Dissertations

This dissertation explores how mathematical and statistical modeling can inform vaccination strategies and evaluate the impact of interventions during infectious disease outbreaks. Motivated by the challenges observed during the COVID-19 pandemic, the research integrates compartmental modeling, Bayesian inference, and agent-based simulation to assess policy effectiveness and disease control across varying contexts. The first study develops a SEIRDV model that incorporates government interventions and vaccination rollout to examine COVID-19 dynamics in Qatar. A Bayesian approach is used to estimate parameters and compute time-varying transmission rates. The model captures shifts in transmission following policy changes and quantifies the reduction in deaths attributable …

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 …

Dickkopf1(Dkk1): A Novel Endogenous Ligand To Prime Nlrp3 Inflammasome Via Tlr4, Theingi Aung

Theses and Dissertations

Dickkopf1(DKK1) is a quintessential Wnt antagonist and immunomodulator in various inflammatory diseases. The underlying molecular mechanisms of DKK1-mediated immunomodulation remain elusive. Here, we identified TLR4 as a new receptor for DKK1 to activate NFκΒ pathway-mediated gene expression and pyroptosis via NLRP3 inflammasome in human and mouse macrophages.

DKK1 employed TLR4 to initiate NFκB signaling cascade via MyD88. MyD88-TAK1-NFκΒ pathway activation by DKK1 increased HIF1α, NFκB, and NLRP3 protein expression levels, leading to pyroptosis. Unlike LPS, DKK1 did not induce IRAK4 phosphorylation, while the interaction between MyD88 and IRAK4 was maintained for downstream signaling activation. DKK1 did not induce IRF3 phosphorylation …

Inorganic Arsenite [I-As (Iii)] Represses Human Renal Progenitor Cell Characteristics And Induces Neoplastic-Like Transformation, Md Ehsanul Haque

Theses and Dissertations

Studies on populations exposed to inorganic arsenic (iAs) have shown an association between this particular exposure and the development of chronic kidney disease (CKD) and renal cell carcinoma (RCC). However, there are few studies addressing how acute exposure of the human kidney to iAs might lead to long-term alterations that might lead to CKD or RCC. This study’s hypothesis is that renal exposure to iAs might alter the renal cells responsible for the repair and regeneration of nephrons damaged by iAs exposure or other renal toxicants. The kidney possesses a minority epithelial cell population that co-express PROM1 and CD24 that …

A Study Of The Effect Of Incentives On Police Recruitment And Retention, Taylor R. Wiggins

Theses and Dissertations

This study examines factors contributing to the staffing crisis in police departments, focusing on officers' perceptions of their organizations. It explores their attitudes toward their departments, motivations for joining law enforcement, and reasons for remaining in their positions. Additionally, the research assesses the impact of various incentives on officer retention.

A total of 140 participants were surveyed, with 113 completing the survey in its entirety, ensuring reliable data analysis. Demographic findings revealed a predominantly male sample (85.8%), with most officers aged between 25 and 44. Analysis of the Minnesota Satisfaction Questionnaire (MSQ) indicated that intrinsic satisfaction (M = 3.85; range …

Incarcerated Youth Returning To Society As Adults: An Examination Of Their Lived Experiences And Challenges, Kimberly R. Lawrance

Theses and Dissertations

When children have been incarcerated, they face collateral consequences that make it nearly impossible to recover from when they return home. Collateral consequences are the adverse effects experienced by incarcerated people and their families often causing restrictions or missed opportunities after interaction with the criminal justice system (Moise, Simonsen, & Kearl, 2023). Collateral consequences can be related to housing, employment, and education, to name a few. These lost opportunities are concerning for youth because most have never held a job or finished high school. Collateral consequences often set them up for failure leading to the revolving doors of jails and …

Next Generation Sequencing Based Profiling Of Genes In Patients With Syndromic Forms Of Retinitis Pigmentosa, Harshavardhini G

Theses and Dissertations

India is one of the largest populations in the world and is estimated to have a high prevalence of Retinitis Pigmentosa (RP). RP is clinically and genetically heterogenous, characterized initially as night blindness, leading to complete vision loss due to retinal degeneration. RP can occur in non-syndromic or syndromic forms, affecting other organs as observed in Bardet Biedl Syndrome (BBS) and Usher syndrome (USH).

BBS is characterized by RP, polydactyly, obesity, renal anomalies and learning difficulties. USH is characterized by RP and sensorineural hearing loss (SNHL), with variable presence of vestibular dysfunction. Nextgeneration sequencing (NGS) has become a cost-effective technology …

Engineering Functionalized Nanomaterials For Targeting And Ablating Biofilms On Surfaces, Dhanush Lakmal Yapa Amarasekara

Theses and Dissertations

Biofilms on both the surface and interior of medical devices pose major challenges, including hindering device performance and serving as infection sources. These biofilms form a protective layer around bacteria, shielding them from the body’s immune system and antibiotics. This makes infections difficult to treat, as the bacteria within the biofilm are resistant to both antibiotics and immune defenses. Additionally, biofilms can induce inflammation and irritation in nearby tissues, leading to further health complications. Antibiotic resistance raises concerns about the emergence of multi-drug resistant (MDR) pathogens. MDR infections are difficult to treat, leading to prolonged hospital stays and the need …

Fisheries Management In Mississippi State-Operated Fishing Lakes: A Review And Look To The Future, Hayden Gregory Funk

Theses and Dissertations

The Mississippi Department of Wildlife, Fisheries and Parks currently manages 18 State Lakes and 17 State Park Lakes to provide public fishing opportunities. My goal was to conduct a comprehensive analysis of monitoring and management activities in State Lakes to enhance understanding of lake dynamics, further develop existing management initiatives, and identify alternative avenues for effective management. To achieve this objective, I have undertaken a comprehensive examination and synthesis of the historical background pertaining to State Lakes and conducted an analysis of pertinent data regarding lake characteristics such as the physical and chemical attributes of the lakes, the features of …

Evaluation Of Current Management Strategies For The Tarnished Plant Bug And Tobacco Thrips In Midsouthern Cotton, Hunter Lane Lipsey

Theses and Dissertations

The tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), is an important economic pest of cotton, Gossypium hirsutum (L.), in the Midsouth region of the United States. An experiment was conducted to determine the impact of insecticide class loss on yield and Lygus populations in the recently commercialized ThryvOn cotton technology. Data indicated no significant yield loss when excluding any currently utilized insecticide class for tarnished plant bug management. An additional objective was to reevaluate the sampling interval necessary to scout ThryvOn cotton for Lygus. No significant differences were observed between a 3 or 7-day sample interval compared to plots …

Description And Influence Of Diseases On The East Mississippi Catfish Industry, And The Role Of Clay Minerals, Iron, And Aluminum Salts In The Susceptibility Of Channel Catfish To Aeromonas Hydrophila And Edwardsiella Ictaluri, Mark Alan Peterman

Theses and Dissertations

In 2014, a virulent clonal group of Aeromonas hydrophila (VAH) was the predominant disease impacting the east Mississippi (EMS) commercial catfish industry. The EMS aquatic ambulatory service observed an area not prone to VAH outbreaks. In addition, frequent underestimations of the scope and economic impact of the EMS catfish industry and its diseases warranted a descriptive effort. Therefore, the EMS catfish industry, its economic impact, the diseases of this region and their economic impact were described. Further, differences in water and geological chemistry of the area not prone to VAH outbreaks, and the sensitivity of VAH and Edwardsiella ictaluri to …

The Long Shadow Of Infection: The Long-Term Implications Of Herpes Simplex Virus And M. Tuberculosis Infection, Lydia Howell

Theses and Dissertations

Infectious diseases and autoimmune diseases, such as multiple sclerosis (MS) and type 1 diabetes (T1D), have traditionally been seen as distinct, with separate etiologies and courses of disease. Recent research has shown that infection and autoimmune disease are more closely woven together than previously thought; certain pathogens like Epstein-Barr virus and M. tuberculosis have been shown to cause long-term disruption to the immune system, for example (Bordignon et al 2011, #1) (Zhang et al 2023, #2) (Bjornevik et al 2023, #3). Conversely, a distinct pattern has emerged in developed countries where as rates of infection fall, rates of autoimmune disease …

A Comparative Study Of Toxicity Propagation Using Epidemiological Models, Niloofar Yousefi

Theses and Dissertations

This dissertation explores the spread and intensity of toxic content on social media, with a particular focus on platform X (formerly known as Twitter). The growing presence of toxic interactions has sparked concerns about their effects on public discourse. Utilizing epidemiological models such as SIR (Susceptible, Infected, Recovered), SIS (Susceptible, Infected, Susceptible), SIRS (Susceptible, Infected, Recovered, Susceptible), SEIRS (Susceptible, Exposed, Infected, Recovered, Susceptible), and the novel SEImIhRS model (Susceptible, Exposed, Moderate Infected, High Infected, Recovered, Susceptible), which are traditionally used to study infectious disease dynamics, this dissertation examines toxicity in platform X discussions. A key contribution of this work is …

Population Genetics Of Deer In The Northern Great Plains, Usa, Sarah Elizabeth Daman

Theses and Dissertations

Deer are currently under threat of chronic wasting disease (CWD) throughout North America. With CWD distribution increasing globally, understanding the spread of the disease is paramount for the effective management and conservation of deer populations. Conservation genomics has been shown as an effective method to study the behavior and movement of individuals on the landscape at a broad spatial scale. This approach allows for a multi-state evaluation of habitat and landscape features that may influence the dispersals and subsequent gene flow between populations. This study was designed to assess the genetic population structuring of deer within North Dakota and surrounding …

Risk Factor Patterns For Elder Abuse Among United States Indigenous Peoples: Native Elder Maltreatment Survey Secondary Data Analysis, Maylynn Riding In

Theses and Dissertations

Elder abuse is a significant public health issue, with findings indicating that 9% to 10% of older adults in the United States experience abuse. This figure is likely mirrored among Indigenous Peoples residing within tribal boundaries, although specific data is scarce. This study aims to fill the gap in understanding the prevalence and risk factors associated with elder abuse among United States Indigenous Peoples (USIP) through a secondary data analysis of the Native Elder Maltreatment Survey (NEMS). The NEMS employs two key instruments: the Hwalek-Sengstock Elder Abuse Screening Test (HS EAST), which is validated for community use, and the Native …

The Effects Of Livestock On Mosquito Diversity And Abundance In Hidalgo County, Taylor Nicole Moya

Theses and Dissertations

Mosquitoes are detrimental to animals and threaten humans. More information is needed on how farm animal presence may impact mosquito abundance and diversity at farms. My goal in this study is to determine if there is any correlation between animal abundance or diversity on a farm and the abundance and diversity of mosquitoes collected. Hidalgo County, Texas, has a subtropical desert climate, ideal for mosquitoes. I hypothesized that the mosquito abundance and diversity indices would increase as the livestock abundance or diversity increases. Adult mosquitoes were collected using two CO2-baited light traps per farm from Spring 2022 to Fall 2022. …

Assessing The Influence Of Native And Invasive Grasses On The Behavior Of Aedes Aegypti In South Texas, Emily Medelez

Theses and Dissertations

Invasive grasses in South Texas can have widespread negative effects, displacing native species, reducing biodiversity, and posing risks to public health. These grasses may flourish in moist, shaded environments, which not only support their growth but also creates habitats favorable for mosquito activity. This can increase the population and alter the behavior of mosquitoes, potentially raising the risk of disease transmission. In this thesis, I look at the behavior of mosquito species Aedes aegypti, primary vector of the yellow fever virus. I analyzed the influence of oviposition, flight and resting behaviors. I tested the relative attraction of Aedes mosquitoes …

Investigating Secondary Metabolites Of Streptomyces And Bacillus Bacteria That Inhibit Colony Growth Of Pathogenic Potato Fungi (Colletotrichum Coccodes, Pythium Ultimum), Jacob R. Henrie

Theses and Dissertations

Potato (Solanum tuberosum) is a crucial global food crop, yet its production is threatened by fungal pathogens such as Pythium ultimum and Colletotrichum coccodes, which cause significant yield losses and impact tuber quality. In this study, we investigated the antifungal properties of various Streptomyces and Bacillus isolates against these pathogens. The Streptomyces isolates, known for their prolific secondary metabolite production, were selected for their varying efficacy against these fungi. Despite the anticipated potential, Streptomyces isolates exhibited limited antifungal activity against Pythium ultimum and only moderate activity against Colletotrichum coccodes. In contrast, Bacillus isolates, particularly B1, demonstrated strong inhibition of C. …

Preparation And Efficacy Evaluation Of Chicken Egg Yolk Sourced Igy Against The Venoms Of Cobra, Krait, Russell’S Viper, And Saw-Scaled Viper, Gayathri G

Theses and Dissertations

Envenomation resulting from snakebites is widely recognized as an alarming health risk in tropical and sub-tropical areas. The big four snakes including Naja naja, Bungarus caeruleus, Daboia russelli, Echis carinatus are responsible for most of the envenomation in India. The current therapy for snake envenomation is immunoglobulins, produced from serum or plasma of horses or sheep. To overcome the drawbacks of current antivenom, chicken egg yolk (IgY) antibodies have recently emerged as one of the most promising research avenues.

In this study, the efficacy of chicken egg yolk sourced antisnake venom (ASV) IgY against the big four venoms was evaluated …

The Relationship Between Health Anxiety, Health Information Seeking Behaviors, And Healthcare Outcomes, Rima Malkan

Theses and Dissertations

The relationship between health anxiety and health information-seeking behaviors (HISB) suggests a possible bidirectional or reciprocal relationship, suggesting that health anxiety leads to HISB and HISB exacerbates health anxiety. The motivations for individuals seeking different types of health information vary and may be impacted by numerous factors that lead to particular health outcomes. However, the impact of these collective variables on healthcare outcomes has not been extensively investigated. The current study aimed to bridge this gap in the literature. The study sample consisted of 133 individuals ages 20-77 years who had varying levels of health anxiety. Results suggested that those …

Bayesian Nonparametric Models For Pooled Data, Yizeng Li

Theses and Dissertations

This work examines two applications of pooling: group testing and pooled biomonitoring. Group testing, introduced by Dorfman in the early 1940s, was initially developed to screen for syphilis among U.S. inductees during World War II. Since then, the approach has demonstrated cost-saving benefits in diverse fields, including drug discovery, genetics, and infectious disease testing. While various regression methods—parametric, nonparametric, and semiparametric—have been proposed to analyze group testing data, they fall short in addressing age-related disparities in disease presence if such variations exist. In Chapter 2, we address this gap by expanding varying coefficient regression within a Bayesian framework to accommodate …

Reaction Toward Potential Resurgent Multiple Risks: Understanding Risk Information Seeking And Behavior In The Post-Pandemic Era, Shudan Huang

Theses and Dissertations

This study applies the Risk Information Seeking and Processing (RISP) model to understand how individuals seek and process information related to overlapping pandemics, including COVID-19, flu, monkeypox, and polio. These overlapping health crises have created a complex media environment, contributing to pandemic fatigue, information overload, and varied preventive behaviors. The research explores how pandemic fatigue influences informational behaviors—such as information seeking, processing, and avoidance—and how these behaviors, in turn, predict preventive behavioral intentions.

Using an online survey of 443 participants, structural equation modeling was employed to test the hypotheses. Results indicate that information insufficiency positively predicts both information seeking and …

Using Machine Learning And Deep Learning Algorithms To Improve Low Birthweight Prediction, Yang Ren

Theses and Dissertations

Low birthweight (LBW) is a major public health issue resulting in increased neonatal mortality and long-term health complications. Traditional LBW analysis methods, focusing on incidence rates and risk factors through statistical models, often struggle with complex unseen data, and thus, their effectiveness is limited in early prevention of LBW, requiring more advanced LBW prediction models. Therefore, this dissertation delves into this important research area by proposing and examining novel machine learning (ML) and deep learning (DL) algorithms, aiming to predict LBW more accurately during the early stage of pregnancy. This dissertation consists of three studies, strategically designed to build upon …

Systemic Inflammation And Neurocognitive Deficits In School-Age Children With Sickle Cell Disease., Elizabeth A. Gillooly

Theses and Dissertations

Sickle cell disease (SCD) causes inflammation that contributes to poor clinical outcomes, including cerebrovascular disease (CVD). CVD can take several forms in SCD, including neurocognitive deficits without visible cerebral infarction. The role of chronic inflammation in cognitive development in SCD has received little attention to-date. We aimed to study novel markers of systemic inflammation: neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and the systemic inflammation index (SII) to describe developmental trends and relationships to cognitive outcomes in SCD at early elementary school-age. Sixty-one children with SCD and no history of stroke were identified who completed an early elementary school age cognitive …

A Study To Explore How People Evaluate The Quality Of Their Medical Information From The Social Media For Celiac Disease, Phillip Arnold

Theses and Dissertations

Every day, millions of people visit various social media platforms to post updates on their daily lives, to search for information, and to repost and/or potentially like posts on social media. This has led to scores of pieces of misinformation appearing on these social media posts. While some misinformation can be harmless and disregarded by the general public, there are various subject matters, including medical treatments and diseases, where misinformation on the treatment and other various subjects involving the disease can lead to dire consequences. This research proposes to investigate how social media users vet their data on two different …

A Novel Perfused Contusion Spinal Cord Injury Model To Assess Rapid Mechanical Properties Changes After Blood Spinal Cord Barrier Breakdown, Laura De Marchi

Theses and Dissertations

Blood-spinal cord barrier (BSCB) disruption exacerbates the tissue damage caused by spinal cord injury (SCI), but the mechanisms and dynamics of how the barrier breakdown affects the mechanical properties of the tissue remain unclear. The perfused bovine ex vivo indentation injury model described here represents a new platform to investigate the short-term effects of altered blood flow and vascular permeability following traumatic spinal cord injury. Our results indicate that injured cords exhibit changes to bulk perfusion, as evidenced by laser speckle contrast imaging, in addition to decreased barrier function shortly after injury. Indentation tests that simultaneously simulate a crush injury …

The Crucial Role Of The Ahr-Ilc3-Il22 Pathway In I3c-Mediated Protection Against Colitis And Associated Microbial Dysbiosis, Chandani Mitchell

Theses and Dissertations

Colitis is an inflammatory bowel disease characterized by dysregulation of the immune system that results in chronic inflammation and dysbiosis. Previously we showed that a naturally sourced aryl hydrocarbon receptor (AhR) ligand, indole-3-carbinol (I3C), was effective in the reduction of colitis-associated disease severity through innate lymphoid type 3 cells (ILC3s) in an interleukin-22 (IL-22) dependent manner. In one of our studies, we used single cell RNA sequencing (scRNAseq) analysis of colonic lamina propria cells from colitis models treated with I3C. Our results indicated that there were changes in the expressions of genes integral to IL-22 signaling when I3C was used …

Histories Of Stress: A Life Course Approach To Population Health In Late Medieval And Early Modern Berlin, Emily Brennan

Theses and Dissertations

Given our current climate crisis and urban population increases, researchers are increasingly interested in the health outcomes at the intersection of climate change and urbanization. Since climate change and urbanization affects human health in a variety of ways, more work is needed in diverse cultural contexts to understand temporal and geographic variations of such phenomena more fully. Using skeletal individuals from 13^th – 18^th century Berlin (n = 387), this project analyses demographic and health trends from the founding of the city in the late medieval period (c. 1200 – 1500) to the early modern period, when the …

Impacts Of Covid-19 And Taliban Takeover On U.S. Afghan Refugee Women’S Mental Health: A Socio-Ecological Approach To Resilience Resources, Atefeh Aghaei

Theses and Dissertations

In response to the escalating global refugee crisis, intensified by ongoing conflicts and environmental changes, this dissertation research focuses on the mental health of Afghan refugee women in the United States (U.S.), particularly in the context of the COVID-19 pandemic and the 2021 Taliban takeover. With over 114 million people displaced globally, Afghan refugees, notably women, encounter heightened mental health risks due to violence, deprivation, systemic persecution, and the challenges of migration. This vulnerability is exacerbated by recent mass traumatic events, including the pandemic and political upheaval in Afghanistan. Our study, conducted through semi-structured interviews with Afghan refugee women and …

Erlang-Distributed Seir Epidemic Models With Cross-Diffusion, Victoria Chebotaeva

Theses and Dissertations

We examine the effects of cross-diffusion dynamics in epidemiological models. Using reaction-diffusion dynamics to model the spread of infectious diseases, we focus on situations in which the movement of individuals is affected by the concentration of individuals of other categories. In particular, we present a model where susceptible individuals move away from large concentrations of infected and infectious individuals.

Our results show that accounting for this cross-diffusion dynamics leads to a noticeable effect on epidemic dynamics. It is noteworthy that this leads to a delay in the onset of epidemics and an increase in the total number of people infected. …