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Investigating Chronic Enterocolitis in Rhesus Macaques (Macaca mulatta) as a Natural Model for Post-Infectious Irritable Bowel Syndrome and the Role of Campylobacter spp. in Disease Development
No full textCampylobacter jejuni and C. coli represent the leading causes of bacterial gastroenteritis in humans worldwide and up to 20% of infections will result in post-infectious irritable bowel syndrome (PI-IBS). Investigations into the pathogenesis of PI-IBS have been hampered by lack of a complete animal model for the syndrome. We aimed to investigate the chronic diarrhea syndrome known as chronic enterocolitis (CE) in rhesus macaques (Macaca mulatta), and the potential contribution of Campylobacter infection to this syndrome, as a naturally occurring model of PI-IBS. We characterized subjective and objective variables in sections of the lower intestinal tract in 16 healthy rhesus macaques and compared these results to a cohort of 37 animals euthanized for CE. Similar to PI-IBS, animals with CE had elevated total leukocyte populations in the large intestine and significantly increased intraepithelial CD3+ T cells in the colon and rectum. Unlike PI-IBS, neutrophils were increased in CE and enteroendocrine cells, enterochromaffin cells, and mast cells displayed no differences between study groups. We then utilized culture, qPCR, and whole genome sequencing (WGS) to characterize the Campylobacter sp. circulating in the study colony. Culture and WGS of 275 samples yielded a non-clonal population of 103 C. coli and 8 C. jejuni isolates, each containing genes for all three subunits of cytolethal distending toxin. Certain MLSTs were found only in animals with intestinal disease and some only in healthy animals. Antimicrobial resistance patterns were similar between these isolates and human reports. qPCR detected a higher prevalence of both bacteria than culture, the quantity of bacteria was significantly higher in animals with intestinal disease, and nearly 1/3 of animals were positive for both C. jejuni and C. coli. Using generalized linear mixed modeling, the only significant risk factor for the presence of Campylobacter sp. or intestinal disease was young age. Ultimately, we added to the understanding of CE, identifying areas where the syndrome overlaps with PI-IBS and areas that warrant further investigation, and advanced our knowledge of Campylobacter sp. circulating in rhesus macaques, allowing honing of future studies to investigate a causal link between the bacteria and CE as exists in PI-IBS
An Exploration of Theoretical and Methodological Typologies of Faith-Based Health Interventions
No full textChronic diseases and conditions continue to pose a significant public health challenge in the United States, affecting a large portion of the population. Unhealthy lifestyle behaviors contribute significantly to chronic disease development, emphasizing the need for effective multi-level health promotion and prevention strategies. Faith communities have emerged as key community partners in addressing health disparities and promoting public health initiatives, particularly concerning chronic diseases. However, despite their commendable efforts, there needs to be more clarity and standardization in defining and operationalizing faith-based health interventions. This conceptual ambiguity hinders the development of evidence-based interventions and limits their effectiveness. This study aims to address the need for more clarity within faith-based health interventions (FBHIs) pertaining to 1) definitions and operationalization, 2) intervention typologies, and 3) conceptual frameworks, guidelines, and models. This systematic review explores the current state of research, implementation, and evaluation of faith-based health intervention typologies and methodologies. Additionally, the theory utilization quality scale (TQS) and methodological utilization quality scale (MQS) were used to assess articles in this review. This review synthesized n=27 articles and highlighted a need for standardized terminology and conceptual frameworks in FBHIs, diverse participant samples, rigorous methodologies, and systematic analyses. While many interventions show promise in improving health outcomes, mixed findings underscore the necessity for robust research designs. The dissertation proposes a faith-based health intervention model and checklist for researchers and practitioners to address current gaps and leverage evidence-based and practice-based approaches
Applying Topology-Based Machine Learning to Risk Stratification in Pulmonary Arterial Hypertension
No full textRisk assessment instruments such as REVEAL Lite 2 can identify patients at high risk for events related to Pulmonary Arterial Hypertension (PAH). However, some patients classified as low or intermediate risk can still experience disease-worsening events, suggesting that these patients are at increased risk beyond that specified by traditional risk stratification tools.
We utilized a dataset of 109 consecutive PAH patients seen between January 2016 and December 2019. PAH-related worsening events occurred in 22 patients. An event was defined as the initiation of parenteral prostacyclin, lung transplantation referral, or death. The 87 patients without an event were used as controls. Echocardiography and REVEAL Lite 2 variables were obtained 4-8 months prior to an event. Topological Data Analysis (TDA), a machine-learning method well-suited to finding hidden patterns in high-dimensional datasets, was used to analyze the dataset. The TDA results then guided Kolmogorov-Smirnov Two-Sample Tests to identify variables differentiating event-prone patients from low-event patients.
Kolmogorov-Smirnov Two Sample Testing of event-prone and low-event patients across all three risk levels showed REVEAL Lite 2 had a KS-Score of 0.303, putting it below echocardiographic variables such as end-systolic eccentricity index (0.625) in terms of differentiating between the two groups.
In this single center machine learning-based study, TDA was able to identify a unique phenotype of patients defined by worsened echocardiographic parameters who were at high-risk of PAH-related events even when deemed low-risk by traditional risk assessment scoring methods. Future risk stratification studies should consider TDA and other machine learning methods
Latinx Individuals in US Sport
No full textThe dissertation central objective is to critically examine the underrepresentation of Latinx individuals in the realm of the United States (US) sport landscape. Commencing with Study 1, a meticulous scoping review of literature was undertaken, revealing a conspicuous research gap spanning four decades, particularly in the context of Latinas in sport. Significantly, 74.1% of the studies surveyed relied on quantitative methodologies, shedding light on the imperative for broader research methods to unravel the intricate dimensions of experiences within this population.
Study 2, grounded in Latin Critical Race Theory (LatCrit), investigated micro and meso-level factors affecting Latinx student-athletes in Predominantly White Institutions (PWI). Despite Diversity, Equity, and Inclusion (DEI) interventions, participants reported encountering racial biases from athletic staff and peers, relying on familial support and campus resources to address these issues. The outcomes underscore the urgent need for initiatives to mitigate disparities faced by Latinx student-athletes.
Subsequently, Study 3 sought to comprehend macro-level experiences of Latinx individuals, undocumented populations, and DACA recipients in the US, with a specific focus on sports participation and community engagement. Grounded in Critical Race Theory (CRT) and Sport for Development and Peace Theory (SFDT), the data collection phase extended over 13 weeks within a Houston, Texas community. Findings illuminated the challenges confronting DACA holders and undocumented individuals in assimilating into new communities, with community-oriented programs identified as pivotal catalysts for positive change.
In conclusion, the dissertation rigorously examines the limitations, theoretical contributions, practical implications, and future trajectories emanating from the tripartite studies. Emphasizing the imperative for diverse research methodologies, it underscores the urgency of addressing racial biases in PWIs and accentuates the pivotal role of community programs in facilitating integration for Latinx individuals, DACA recipients, and undocumented populations within the sporting milieu
Evaluation of the Interaction of an Insecticidal Peptide and Bt Proteins or a Baculovirus for Managing Helicoverpa zea in Bt Cotton
No full textThe cotton bollworm, Helicoverpa zea (Bobbie), is a major and damaging pest of cotton, corn, sorghum, and other crops. This pest has developed field-evolved resistance to the Cry1 and Cry2 Bt proteins, and there are early warning signs for resistance to Vip3Aa. Chlorantraniliprole is the primary insecticide used to manage H. zea in sorghum and Bt-resistant H. zea in cotton. There is concern that overutilization of chlorantraniliprole may lead to resistance. Utilizing IPM-friendly biopesticides may be an alternative means for managing H. zea in cotton and sorghum. Spear RC (HXTX) is a new biopesticide derived from spider venom, but because this product requires aid from Bt to penetrate the mid-gut, its utility is diminished. However, cotton expressing Bt proteins may be able to serve as facilitators although it is uncertain if they will function for Bt resistant H. zea. Alternatively, Heligen (HearHPV), a Heliothine-specific virus, may also act as a facilitator for HXTX.
Experiments were conducted to determine the interaction between Bt proteins and HXTX on Bt-susceptible, Cry-resistant, and Vip-resistant H. zea. In diet-based bioassays in the absence of any Bt proteins, HXTX alone exhibited marginal activity on susceptible, Cry-resistant, and Vip-resistant H. zea, but when combined with overlays of 10��g/cm�� of Cry1Ac, toxicity to Cry-resistant H. zea was higher. However, the addition of 5��g/cm�� of Vip3Aa39 did not enhance HXTX toxicity to Vip-resistant H. zea. This suggests that Vip3Aa resistance probably involves binding site resistance, while Cry-resistance probably allows binding and some pore formation. Thus, Cry1Ac Bt protein expressed in cotton will serve as an effective facilitator toward H. zea that are resistant to Cry1Ac.
Diet-based bioassays were used to determine if HearNPV may serve as a facilitator for HXTX targeting Bt-susceptible and Cry-resistant H. zea. Neither HXTX alone nor HearNPV alone at LC������ and LC������ dosages had great activity towards H. zea. Against Bt-susceptible H. zea, when HXTX was combined with HearNPV there was a significant interaction and synergistic effect, but this relationship was not as pronounced with the Cry-resistant H. zea strain. Thus, HearNPV may serve as facilitator for HXTX, but it appears to be less consistent than Bt proteins.
In 2022-2023, field tests were conducted to field validate laboratory findings demonstrating the potential of utilizing HXTX for H. zea management in non-Bt and Bt cotton. Despite laboratory assays suggesting that HXTX has activity on H. zea when used in conjunction with Bt proteins, we were unable to demonstrate significant activity in cotton in the field. This was mostly likely due to inadequate spray coverage, residual persistence, and the lack of translaminar activity for HXTX
The Hepatic Biotransformation Capability and Occurrence of Emerging Contaminants in American Alligators (Alligator Mississippiensis)
No full textRecently, emerging contaminants (ECs) have been drawing more attention due to health concerns in exposed organisms. Pharmaceuticals and per- and polyfluorinated substances (PFAS) are representative ECs that are ubiquitous and persistent in aquatic environments. American alligators (Alligator mississippiensis) are often considered a sentinel species in coastal aquatic ecosystems along the Gulf of Mexico as they are susceptible to the bioaccumulation of contaminants due to their high trophic position and longevity. However, the biotransformation capability of alligators for ECs and EC exposure impact in wild alligators are yet to be understood. Therefore, this study aimed to address these knowledge gaps.
For the evaluation of biotransformation capability, a novel in situ liver perfusion system was developed using juvenile alligators. The operativity of perfused livers was tested with normoxic and hypoxic treatments. Under normoxia, the aspartate transferase (AST) and lactate/pyruvate ratio in effluent perfusate remained stable for 6 hours whereas hypoxia significantly increased the lactate/pyruvate ratio after 2 hours. The elevation of lactate suggests the induction of anaerobic metabolism indicating the viability of the organ. With the establishment of operable perfused livers, alligator biotransformation capability for carbamazepine (CBZ) and nicotine (NCT) was investigated by measuring the formation of their primary metabolites. Additionally, the in vitro S9 assay was performed to compare its metabolic potential with perfused livers. For CBZ, perfused livers exhibited only 30% intrinsic formation clearance (CLf,int) relative to the S9 assay. The NCT metabolism was only observed in perfused livers. Compared to the corresponding rat models (S9 or perfused livers), alligators��� CLf,int was 20-60% for CBZ and 50% for NCT of rats. Lastly, wild alligator plasma was analyzed for select ECs and biochemistry parameters. The detected ECs included amphetamine, atenolol, ketoprofen, naproxen, nicotine, and perfluorooctane sulfonic acid. Statistical analyses showed positive correlations between the plasma EC levels and biochemistry indicating potential physiological stress associated with organ injury and endocrine disruption. While this study provides invaluable insight into the metabolic capability and vulnerability to EC exposure in alligators, the methods developed in this study can also serve as an effective toolbox for future studies to protect this ecologically important species
OSHA Citations and Beyond: Strategies for Ensuring Combustible Dust Compliance
No full textManaging dust in the ever-changing world of industrial operations cannot be emphasized enough. Dust, frequently observed due to numerous industrial processes, poses several complex challenges that require careful consideration and proactive control. The appropriate handling of dust emerges as a crucial component of industrial processes, from the standpoints of safety and health to the optimization of operational efficiency. This project outlines the OSHA (Occupational Safety & Health Administration) citation data that was gathered against the citations obtained in response to the "dust" query from 2019 to 2023. The data from the citations was studied to understand which type of industries had received the most citations from OSHA. Furthermore, the equipment of concern was studied and analyzed, and the citations received from 2019 to 2023 were then compared with 2018, explaining the relevance of the shifting industries, citations, and industrywide concerns about handling dust within the above-mentioned timeframe. In total, there were 45 citations related to dust in 2018, which decreased over the years. In 2023, 42 citations were found under the general duty clause in the term "dust." There were also some citations where NFPA (National Fire Protection Association) standards were outlined, referred to, and explained. In the years considered in the project, over 95 percent of citations were classified as ' serious, ' with scarce instances of 'failure to abate' and ���willful��� violations. All penalties were compared case-wise, industry-wise, and year-wise to understand the cost relationships with incidents. New citations after the year 2018 were also assessed and evaluated. Further measures and standard requirements to ensure safety compliance against dust hazards were discussed in detail. This project emphasizes the critical significance of managing dust in industrial operations, highlighting its multifaceted challenges and pivotal role in safety, health, and operational efficiency. Through a detailed analysis of OSHA citation data from 2019 to 2023, industry trends, equipment concerns, and penalty assessments were investigated, providing a comprehensive understanding of the evolving landscape and imperative measures for ensuring safety compliance in handling dust hazards
Structural Analysis of Irregular Cracking in Continuously Reinforced Concrete Pavements
No full textThis research study explores the analysis of irregular cracking in continuously reinforced concrete pavements (CRC) using a synergized approach of analytical and numerical methods. A Python script was developed to execute linearized finite difference analysis, assessing temperature and moisture profiles to compute environmental stresses, including thermal and shrinkage effects. This script integrates these stresses with user inputs to run finite element analysis using the ABAQUS solver. Concurrently, the study provides a revision of the AASHTO crack spacing formula presented in the Mechanistic-Empirical Pavement Design Guide (MEPDG) for CRC pavements. The modified formula addresses the limitations of the previous version, providing insight into the depth of crack initiation. The study uncovers several key insights into early-age cracking in continuously reinforced concrete pavements including -but not limited to- variations in temperature and moisture profiles across different locations and seasons that significantly impact the cracking mechanism. Longitudinal steel cover is found to be a critical factor, with smaller cover increasing the likelihood of top-down. The study also reveals that while active cracking control is effective in determining crack locations, its efficiency is compromised when the bonding to the underlying layer is weak. Ultimately, the high bonding strength between PCC slabs and the underlying layer not only increases the possibility of bottom-up cracking but also decreases crack spacing
Supplementation of Oral Probiotics to Freshly Weaned Lambs When Transitioning to a High Concentrate Diet in Conjunction with Parasite Resiliency to Copper Wire Boluses
No full textRumen health is vital to post weaning health and performance in all ruminant species. Sheep are fed high concentrate diets to improve growth rate, however, these high concentrate diets can lead to acidosis, or even mortality, if not fed correctly. Acidosis is caused by the increased consumption of grain and a drop in pH. The hypothesis that administering a probiotic supplement to lambs prior to and during the feeding period would improve the post-weaning gain as well as decrease mortality. For this study, 93 finewool lambs (n=93; females, n=45, males, n=48) were weaned at approximately 90 days of age and had an average body weight (BW) of 24.7 Kg. Each lamb was assigned randomly to one of the three treatment groups: Control (CON), Treatment 1 (TRT 1), and Treatment 2 (TRT 2). Lambs assigned to TRT 1 and TRT 2 received an oral dose of probiotics (ProBios, Menomonie, WI), which contained four lactic acid producing bacteria: Enterococcus faecium, Lactobacillus acidophilus, Lactobacillus casei, and Lactobacillus plantarum. Lambs in CON received 0g of Probios (n=31, females, n=15; males, n=16), lambs in TRT 1 were administered 10g of Probios on Day 0 (n=31, females, n=15; males, n=16), and lambs in TRT 2 were administered 10g of Probios on Day 0 and Day 7 (n=31, females, n=15; males, n=16). Lambs were housed in groups of three in a fully covered barn with automatic waters. Lambs were sorted into groups by treatment, sex, and initial weight. Lambs were limit fed for 12 days with hay to aid in transition to the high concentrate diet; after the 12 days, they were then fed ad libitum. For six weeks, body weight (BW) and FAMANCHA (FAM) scores were collected. Blood was also collected for the first four weeks and fecal egg counts (FEC) were collected on weeks 1, 4, 5, and 6. There was no interaction between treatment group and weight gain, however, female lambs were statistically lighter when compared to male lambs. Female lambs had a lower FAM score when compared to males.
An additional study of Copper Oxide Wire Particle Boluses (COPWs) was conducted to determine the effectiveness when compared to regularly used anthelmintics. Lambs received an oral drench of Valbazen, Cydectin, and Prohibit (n=44) or a COWP Bolus (n=41). After week one lambs who received oral anthelmintics had a statistically lower FEC when compared to lambs who received COPWs. There was not a significant difference between COPWs and dewormer by Week 2
Essays in Monetary Policy and Household Expectations
No full textThis dissertation focuses on the formation and implications of household beliefs and expectations with respect to monetary policy.
In the first chapter, I investigate whether consumer sentiment (analogously referred to as confidence) matters for monetary policy. Specifically, I consider whether consumer sentiment responds to monetary policy shocks, as well as whether the responses of output, inflation, and unemployment depend on the state of consumer sentiment. Although various methods of measuring confidence/sentiment exist, the underlying goal of each is to gauge how the normative economic attitudes of households change over time. As such, asking whether consumer sentiment responds to monetary policy shocks can alternatively be viewed as whether monetary policy shocks change households��� perceptions of the current/future state of the economy. Additionally, while some of the variation in sentiment reflects movement in aggregate fundamentals, a number of papers have established that the unaccounted for portion has predictive power for a variety of macroeconomic variables. This observation motivates considering whether the state of consumer sentiment suggests different macroeconomic impacts of monetary policy shocks.
Using an external identification scheme in a local projections (LP) approach, I find that contractionary monetary policy shocks have only minor negative effects on consumer sentiment. Consumer sentiment is measured by the headline index published by the Michigan Survey of Consumers. Further, I find that this minor response persists across various states of inflation, business cycles, and interest rates. In contrast, I do find evidence that the state of consumer sentiment matters for how output, inflation, and unemployment respond to these shocks. Specifically, positive interest rate shocks during periods of depressed consumer sentiment have quicker and more contractionary effects on output and unemployment, while inflation is not responsive over short nor long term horizons.
In the second chapter, I utilize a novel feature of the Michigan Survey of Consumers (MSC) to identify whether respondent expectations change within tight windows around macroeconomic data releases. This feature of the data is the interview dates of respondents between June 1979 ��� May 2019. Over this period, I include releases of the Employment Situation Summary (ESS), Consumer Price Index (CPI), Industrial Production (IP), and Gross Domestic Product (GDP), as well as Federal Open Market Committee (FOMC) meetings and calls. Incorporating the interview dates of each respondent alleviates a major identification problem that has prevented previous empirical work from using the MSC data to address such a question. Without them, one would only know which survey the person was interviewed for, but not when it was conducted. Thus, it was not possible to discriminate between the different information sets of the respondents, thereby preventing identification of the change in inflation expectations in response to a particular release.
My work in this paper furthers our understanding of household inflation expectations along a number of dimensions. First, I find that expectations significantly respond to information about the unemployment rate and CPI inflation, indicating that these are more salient to households than the other releases. I measure the information being conveyed by the releases by using the size and sign of changes in the release relative to the previous periods value. Second, I consider whether the relevance of these releases differs during recessions, the first paper to empirically address such a question. I find that information about the unemployment rate is particularly salient preceding, during, and following recessions. The final contribution I make in this paper is the finding that, over a shorter subsample, unanticipated changes in output growth prompt households to adjust their inflation expectations. Here, unanticipated refers to the difference between the realized value and Bloomberg consensus forecast value for each release, wherein inflation expectations respond to such deviations in IP and real GDP growth