Association between same-sex experience and prevalence of subclinical cardiovascular disease among U.S. adults, 1999 – 2004

Background: Previous literature has indicated higher levels of cardiometabolic risk factors and cardiometabolic-associated biomarkers among sexual minorities than heterosexuals. It is thus important to examine if there is a corresponding higher prevalence of subclinical cardiovascular disease among sexual minorities. No previous studies have examined the prevalence of subclinical cardiovascular disease among a representative population of adult sexual minorities. We hypothesized that persons reporting any lifetime same-sex experience (SSE) would have higher burden of subclinical cardiovascular disease than heterosexuals. Methods: We conducted a cross-sectional study of 5,938 participants aged 20 to <60 years without cardiovascular disease in the National Health and Nutrition Examination Survey 1999-2004. We used multivariable logistic regression to evaluate the association of any lifetime SSE with elevated high-sensitivity cardiac troponin T (hs-cTnT), high-sensitivity cardiac troponin I (hs-cTnI), and N-terminal B-type natriuretic peptide (NT-proBNP), biomarkers of cardiovascular disease. Results: The prevalence of SSE was 5%. After adjustment for confounders, we found no statistically significant associations between SSE and elevated levels of hs-cTnT, hs-cTnI, or NT-proBNP. Effect estimates for hs-cTnT were attenuated from the unadjusted model after adjusting for demographics (Model 1 OR 95% CI: 0.48 [0.23, 1.00]) and additional behavioral and cardiometabolic risk factors (Model 2 OR 95% CI: 0.48 [0.23, 1.02]). For hs-cTnI and NT-proBNP, respectively, there were no notable patterns from the unadjusted (OR 95% CI: 0.76 [0.34, 1.69]) to the adjusted models (Model 1 OR 95% CI: 0.78 [0.35, 1.73]; Model 2 OR 95% CI: 0.76 [0.33, 1.74]) and from the unadjusted (OR 95% CI: 0.68 [0.40, 1.15]) to the adjusted models (Model 1 OR 95% CI: 0.68 [0.42, 1.09]; Model 2 OR 95% CI: 0.66 [0.41, 1.05]). Conclusion: Counter to our hypothesis, we did not find evidence to suggest that persons reporting SSE had a higher burden of subclinical cardiovascular disease. Future research is needed to characterize the burden of subclinical cardiovascular disease among sexual minorities using contemporary data collected from a sizable sample of older adults

ASSESSING THE PROVISION AND EQUITABILITY OF PRIMARY CARE IN A LOW-RESOURCE SETTING

Introduction: To inform policies to promote well-being and eliminate health inequities in all settings, this dissertation focuses on an often-cited necessity for population health and heath equity—primary care—by pursuing the following aims: 1) conducting a review of the literature on the impact of primary care features on health access inequities 2) investigating the association between primary care experience (PCE) and the likelihood of hospitalization for chronic ambulatory care sensitive conditions (ACSCs) & inequities in the likelihood of hospitalization for chronic ACSCs among adults in rural Bihar, one of India’s socioeconomically backward states; and 3) investigating the association between the quality of local primary care—measured as average provider competence—and an individual’s self-rated health (SRH) & inequities in SRH in rural Bihar, India. Methods: The 1st aim uses the scoping review approach. The 2nd and 3rd aims analyze data collected through household and provider surveys conducted under a parent study set in Bihar, India, using logistic regressions to model the odds of hospitalization and poor SRH as a functions of PCE and average provider competence, respectively, including interactions with markers of inequity. Results: Primary care interventions are largely associated with improvements along the health access continuum for disadvantaged and advantaged populations, oftentimes with greater improvements for disadvantaged populations. Better PCE is associated with reduced likelihood of hospitalization for chronic ACSCs among adults. Individuals in the poorest wealth quintile with better PCE experienced the largest drop in the likelihood of hospitalization, compared to higher wealth quintiles. Better quality of local primary care, beyond a threshold, is associated with better individual-level SRH, although improvements in SRH appear to inequitable by gender and age. Conclusion: This dissertation provides support for the strengthening of primary care systems, particularly in LMICs to tackle the burden of chronic primary care sensitive conditions and health inequities. Findings also highlight the importance of ensuring that the local quality of primary care is of an adequate standard to promote population health. More studies are needed to evaluate the quality of primary care and the reasons behind inequities in access to primary care in lower income countries

Exploring global change impacts on plant-plant and plant-microbe interactions of grassland species

Grassland plants exist in complex environments, where in addition to coping with environmental conditions, they also interact with other plants in their vicinity as well as with microbes in the soil. How these are affected by global environmental changes need to be better characterized to predict ecosystem functions. My dissertation experimentally explores the global change impacts on plant-plant and plant-microbe interactions in grassland species. In my first chapter, I examined how drought and a soil mutualistic microbe, arbuscular mycorrhizal fungi (AMF), affected the relationship between genetic diversity and productivity of a dominant tallgrass species, using a mesocosm experiment. I found that while genetic diversity and AMF had no effect on productivity, drought differentially affected productivity and functional traits of genotypes of a dominant grass, which implies that drought can have variable outcomes for different genotypes within a same species. In my second chapter, I tested the Stress Gradient Hypothesis, which hypothesizes that plant-plant interactions shift from competition to facilitation with increasing environmental stress. I subjected two co-dominant grasses to drought, elevated CO2, and varying levels of plant-plant interactions. My results demonstrated that plant-plant interactions leaned towards facilitation with decreasing stress gradient, contrary to the stress gradient hypothesis. In the third chapter, I investigated the tripartite relationship among a legume, and two mutualistic microbes, AMF, and rhizobial bacteria, under elevated CO2. I tested the hypothesis that the tripartite relationship depends on the cost of carbon to plants and benefit of nutrients from mutualists, and consequently, elevated CO2 should alter this relationship. I conducted a pot experiment under different CO2 and mutualist treatments. My findings suggest that dual inoculation of the legume with AMF and rhizobia comes with carbon costs, which decreases under elevated CO2. The intricate relationships between global change, plant-plant and plant-microbe interactions collectively shape the response of grassland species to global change. In summary, my dissertation advances our understanding of the context dependency of global change impacts on plant-plant and plant-microbe interactions. This research contributes not only to ecological theory but also to the development of strategies for sustainable grassland ecosystems in a changing world

IMPACT OF HIV ANTIRETROVIRAL THERAPY ON THE EUKARYOTIC GUT VIROME AND HOST HEALTH

Antiretroviral therapy (ART) is prescribed to people living with HIV (PLWH) or to individuals taking it as pre-exposure prophylaxis (PrEP). In PLWH, ART can significantly reduce viral loads to undetectable levels and prevent Acquired Immune Deficiency Syndrome (AIDS). Despite ART efficacy, PLWH are still at elevated risk of multiple chronic diseases, including metabolic syndrome (MetS). The microbiome of PLWH has been shown to differ from that of HIV-negative individuals, even when receiving ART, suggesting a potential role for an ART-modulated gut microbiome in chronic disease pathogenesis. However, whether ART itself can directly modulate gut microbiome/virome, and specifically endogenous gut eukaryotic viruses, remains unknown. Here, we raise the hypothesis that ART itself has direct collateral impacts on gut eukaryotic viruses and that this modulation contributes to the increased risk of non-infectious disease. In this thesis work, I assessed the impact of antiretrovirals (ARVs) given individually (abacavir (ABC), dolutegravir (DTG), lamivudine (3TC), emtricitabine (FTC), tenofovir alafenamide (TAF), and tenofovir disoproxil fumarate (TDF)) or in combination (cART, TDF/FTC/DTG) on the metabolic health of HIV-naïve mice. Individual ARVs, as well as cART, exacerbated diet-induced weight gain (3TC, DTG, and TAF) and glucose intolerance (3TC, TAF, and FTC). Preliminary profiling revealed that DTG and FTC altered the gut microbiome while DTG and TDF altered the virome. To explore the mechanisms through which ART alters the virome, specifically eukaryotic viruses, I aimed to determine how different ARVs impact eukaryotic virus-host cell interactions in vitro. A universal concentration of ARVs (ABC, DTG, 3TC, FTC, TAF, and TDF) that does not affect Caco-2 and BHK-21 cell viability was determined. Viral plaque assays were also calibrated and preliminary experiments with ARV treatment was performed. Overall, this work suggests an association between the direct impact of ARVs on the gut microbiome/virome and MetS, and provides a framework to explore the mechanisms of eukaryotic virus modulation by ART

The Transformative Use of Technology to Teach

Although teachers in Singapore, enabled by one-to-one learning, have access to and knowledge of technology tools, most struggle to transform how technology is used for instruction. Transformation refers to a fundamental shift in the way digital technology is used for instruction, which includes moving away from teacher-centred approaches towards higher-order learning and more student-centred and student-initiated learning that may not be possible without technology. A literature review revealed that extrinsic factors such as leadership support and peer influence, as well as intrinsic factors such as technology knowledge, self-efficacy and belief, were critical in influencing teachers' transformative use of technology to teach. A needs assessment involving 21 teachers based on a mixed-methods sequential explanatory approach was conducted. Findings showed that while low levels of knowledge and self-efficacy were largely responsible for teachers’ struggle to transform how they used technology for instruction, peer influence was crucial in helping teachers learn and adopt new approaches to teaching with technology. A 16-hour professional learning intervention over eight weeks was proposed in which teachers learned about new technologies, approaches, and associated pedagogies, documented concrete plans of action and reflected on their learning, designed a classroom activity and received feedback from a colleague who would observe their classroom teaching. To enable the school to adopt elements of the professional learning intervention as part of its regular and on-going professional learning programme, a mobile application (Pedagram) to help teachers conduct lesson observations as well as a video creation template to support teachers create a school-based repository of technology videos were developed. The overarching intent was to empower teachers to take control of their own professional learning

BRIDGING THE GAP IN ROBOT-ASSISTED SURGICAL TRAINING: A SYSTEMS APPROACH

The central goal of any surgical residency training program is to prepare physicians and surgeons for independent practice within an outcome-based, peer-reviewed system. Despite significant reforms by the American Council of Graduate Medical Education (ACGME) to establish competency-based education (CBE) models, there is severe variability in the quality of robotic-assisted surgery (RAS) training for surgical residents, leading to disparities in their preparedness for independent practice. This dissertation examines urology residents' perceived training and assessment variability, focusing on their confidence and competence in RAS procedures. Using Bronfenbrenner’s Ecological Systems Theory (EST) as the theoretical framework, this study analyzes the multi-layered influences on residents' training experiences within an urban academic medical center. Data were collected from 16 faculty and 16 residents through surveys, revealing three pivotal themes for refining RAS training: enhancing structured training programs, increasing simulation-based training, and integrating early exposure to RAS techniques. Key findings indicate that residents report diverse experiences and varying levels of exposure to RAS procedures, with significant gaps in mentorship and feedback. Both residents and faculty recognize the importance of tailored training programs, but discrepancies exist in perceptions of intraoperative danger, time efficiency, and skill acquisition rates. Identified barriers include limited autonomy for residents, competing institutional priorities, and the need for extra time for effective teaching. The study underscores the need for standardized and comprehensive RAS training programs to ensure consistent, high-quality education. Addressing identified barriers and aligning training approaches with resident and faculty expectations can enhance residents' preparedness, competence, and confidence in robotic surgery, ultimately improving patient outcomes and advancing the field of urology. This dissertation provides actionable recommendations for developing structured training pathways, incorporating diverse educational tools, and fostering a cohesive educational environment. This research aims to equip future surgeons with the necessary skills to excel in advanced minimally invasive procedures by bridging the gap in RAS training

Responses to respiratory virus infection and immunization

Respiratory viruses lead to millions of cases of illness and thousands of admissions to hospitals and fatalities annually, such as measles and SARS-CoV-2. The fundamental preventive measures to reduce the risk of respiratory viruses is immunization, which helps people defend themselves from viruses and severe illnesses. However, safe and effective vaccines for respiratory viruses are still a major challenge to public health. In 2023, the United States reported approximately 900,000 hospital admissions for COVID-19 and 58 measles cases. The measles virus triggers immune suppression, leading to secondary infections like pneumonia and diarrhea, by depleting memory B and T cells. Individuals infected with SARS-CoV-2 may suffer long-term consequences, including Long COVID, a chronic condition that causes health problems that may require extensive care. The aim of this study is exploring the replication tropism of liveattenuated measles virus, evaluating the efficacy of a new measles vaccine, and the impact of convalescent plasma therapy on COVID-19 patients. These studies identified sites of LAMV replication in vivo and determined that a new recombinant measles vaccine could be a potential option for the immunocompromised group. After treatment with convalescence plasma, few COVID-specific antibody-secreting cells were found. The study is crucial in investigating and uncovering aspects of respiratory virus infections and immunization strategies, significantly contributing to public health knowledge and outcomes

TEMPORAL CHANGES IN HIV AND HCV PREVENTION AND HARM REDUCTION EFFORTS AMONG PEOPLE WHO INJECT DRUGS IN BALTIMORE, MARYLAND

Background: The opioid epidemic and the COVID-19 pandemic induced structural and social changes that may jeopardize efforts to eliminate HIV and HCV infection. This dissertation examines temporal changes in HIV and HCV prevention and harm reduction efforts as well as HIV and HCV seroincidence among people who inject drugs (PWID), both before and during the opioid epidemic, and assesses changes in the use of medications for opioid use disorder (MOUD) and support services among PWID before and during the COVID-19 pandemic. Methods: This multi-method study was conducted among community-recruited PWID in Baltimore, Maryland that were enrolled in the AIDS Linked to the IntraVenous Experience (ALIVE) cohort study. Temporal trends in combination HIV and HCV prevention efforts and seroincidence were examined between January 1988 to December 2019 using semi-annual ALIVE survey visit data collected from 5,506 participants. Qualitative data from the Covid Health And Network Group Experience Study (CHANGES) nested within the ALIVE cohort, which included data from 28 in-depth interviews conducted between July 2021 and February 2022 with PWID, explored how structural and social changes due to the COVID-19 pandemic influenced individual-level experiences with MOUD and support service utilization. Finally, temporal changes in engagement in treatment with MOUD and support services were examined before versus during the COVID-19 pandemic using an interrupted-time series approach among 780 PWID in the ALIVE study between December 2015 to November 2022. Results: Before the COVID-19 pandemic, we observed substantial increases in the combination HIV and HCV prevention efforts, including increases in methadone use from 14% in 1993 to 44% in 2019, but gaps in service coverage still remained in 2019. Between 1988-1992 and 2017-2019, there was a 97% reduction in HIV seroincidence. While HCV seroincidence also initially declined, HCV seroincidence in 2017-2019 was similar to levels in 1988-1992 after adjustment for demographic characteristics (IRR=1.25 [95%CI=0.64-2.45]). Following the onset of the COVID-19 pandemic, there were many structural and social changes that created new barriers and facilitators to engagement in methadone use and related support services. Namely, pandemic-related changes in methadone dispensation policies and practices, such as increased flexibilities for take-home methadone doses, temporarily served as facilitators of methadone engagement. Some drug treatment programs were closed because of the pandemic and others newly offered telehealth services, such as for support group meetings. However, the quality of both in-person and virtual support group meetings during the pandemic were not favorably viewed by participants, further hindering their engagement in support services. At a population-level, the onset of the COVID-19 pandemic was associated with an immediate reduction in attending group counseling/support services (13.1% [95%CI=17.4%,8.6%]) as well as a negative impact on the trajectory of attending them. In contrast, there were limited changes in buprenorphine use or methadone use associated with the pandemic; however, methadone use declined over time, starting just before the pandemic. Conclusions: Before the COVID-19 pandemic, there were substantial gains in the control of the HIV epidemic among PWID in Baltimore, whereas HCV transmission was rampant in this population. The COVID-19 pandemic disrupted engagement in drug treatment and related services; however, structural adaptations including to service delivery helped mitigate its impact on the use of MOUD. This highlights the resiliency of the health system to a large societal disruption and that positive structural changes can protect the health of PWID during societal disruptions and in everyday practice. Programs should focus on expanding the coverage of combination HIV and HCV prevention efforts among PWID, with special emphasis on MOUD as it also has implications for mitigating other drug-related harms (i.e., the overdose crisis)

Self-Regulation in Addressing Math Anxiety in High-Achieving Students in an Affluent Asian American Community

Adolescent learners in a high-achieving school in an affluent, predominantly Asian, and Asian American community in a suburb of Silicon Valley, California, face a myriad of stressors and challenges impacting their math achievement. Existing literature suggests parenting styles, ability-grouping practices, and self-beliefs including math anxiety are a few of the salient factors impacting adolescents’ math achievement. A mixed methods needs assessment was conducted to understand the portrait of a struggling math student through the lens of 16 teachers using a mixed methods design. Results indicated divergent beliefs surrounding math education and a sense of pressure for children to take advanced math classes. Self-regulatory interventions such as mindfulness exercises have been shown to reduce math anxiety. Expressive writing was used as an intervention on math anxiety in 69 7th-grade students in a mixed methods convergent parallel intermittent time series design. Parents (N=16) were interviewed to provide insight on their children’s math learning experiences. Students’ math anxiety levels were not significantly related to the expressive writing. Students’ writing content included themes of parents’ expectations, peer relations, perceptions of math teachers and classrooms, and reflections around math anxiety. A range of themes also appeared in parent interviews including parents’ experiences with schooling in other countries, navigating their children’s school system, and emphasizing performance, well-being, and/or effort in their children. Further research examining antecedents to math anxiety and additional interventions to reduce math anxiety are suggested

Institutional Barriers to Innovation in Public Education: A Case Study in Innovation in Public Education in Washington State

Innovation in public education is restricted by the forces of institutionalism, namely mimetic, normative, and coercive isomorphism. As a result, school leaders struggle to find ways to innovative to meet the unique demands of their students, often conforming to district, state, and federal policies that prevent them from designing new school systems and practices. In Tacoma, WA a school leader acted as an educational entrepreneur, designing and opening three high schools inside the third-largest public school district in Washington State over the course of two decades. Using a theory of strong ties, this case study explores the case from its inception in a large comprehensive high school in the mid-1990s to the present day, where the three high schools operate under a school board policy that allows them more freedom to innovate and change. The case study uses qualitative interviews and documents to develop a narrative, social network analysis, and critical event analysis to develop the story of how this school leader was able to create three new high schools inside a large public institution