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EVALUATION OF THE IMPACTS OF HURRICANE-RELATED FLOODING ON DELAYS IN INITIAL CANCER-DIRECTED CARE IN NORTH CAROLINA
Get PDFWith the rising intensity and frequency of hurricanes driven by climate change, these events have become critical disruptors of healthcare systems and contributors to health inequities. This dissertation explores how hurricane exposure impacts health outcomes and median time to initial treatment through two complementary studies. In Aim 1, a scoping review synthesized 292 epidemiologic studies on hurricane-related health outcomes, revealing a wide variation in how hurricane exposures were defined and providing a comprehensive summary of the methods, outcomes, and populations examined across studies. Mental and maternal health outcomes were most commonly studied, while cancer and infectious diseases remained underexplored. The review highlighted considerable heterogeneity in exposure assessment methods, with most studies relying on self-reported or administrative exposure measures. Expanding research to include a broader range of health outcomes, alongside validated exposure and outcome measures, is essential to better understand the magnitude and differential impact of hurricanes on population health. Aim 2 applied a controlled interrupted time series design to evaluate whether exposure to Hurricanes Matthew (2016) and Florence (2018) disrupted median time to treatment initiation among patients diagnosed with breast, colorectal, or lung cancer in North Carolina. Using county-level FEMA disaster declarations, no significant overall treatment delays were observed. However, when applying ZIP code-level flood extent data from the North Carolina Flood Extents Archive (FLDEX), we found significant immediate delays in median time to initial treatment among colorectal cancer patients residing in high-flood exposure areas. Subgroup analyses showed more pronounced delays among rural residents, older adults, and non-Hispanic Black patients, suggesting underlying structural inequities that shape vulnerability to disaster-related health disruptions. Together, these studies contribute to the growing body of evidence on the limitations of current hurricane health research. The findings support the need for resilient healthcare infrastructure and targeted preparedness strategies to ensure continuity of care, particularly for cancer patients in high-risk areas. This dissertation provides critical insights for advancing disaster health research, improving hurricane exposure measurement, and guiding equitable policy and public health responses amid a changing climate.Doctor of Philosoph
Quantifying Mortgage Credit Risk Arising from Flooding During Hurricane Florence
Get PDFFloods are the costliest natural hazard in many regions and can be financially devastating for homeowners and mortgage lenders. This research uses a unique dataset composed of consumer credit data and modeled flood damage to investigate relationships between flooding during Hurricane Florence and the odds of deep delinquency and prepayment among impacted households in Eastern North Carolina. Delinquency can lead to default and foreclosure for the homeowner while prepayment can lead to loss of income for lenders. Households exposed to flooding had 2.47 times greater odds of experiencing deep delinquency and 1.73 times greater odds of prepaying a mortgage. Results also explore how these estimates vary depending on time and other relevant covariates. Results demonstrate the magnitude of the financial risk associated with floods. Homeowners, lenders, and governments can use these results to inform risk management strategies to protect mortgage borrowers and the institutions which make mortgage lending possible.Master of Scienc
ON THE MACROSCALE MODELING OF TWO-FLUID FLOW IN POROUS MEDIUM SYSTEMS USING THE THERMODYNAMICALLY CONSTRAINED AVERAGING THEORY
Get PDFTwo-phase fluid flow in porous media is a critical problem with broad applications, including subsurface contaminant transport, global climate models, hydraulic fracturing, and enhanced oil recovery. Traditional models, such as Richards' Equation and the two-phase flow model, rely on phenomenological approaches at the macroscale, which lack precision due to empirical closure relations, assumptions of local equilibrium, and the absence of direct connections to microscale physics. These limitations hinder predictive accuracy, particularly in non-equilibrium scenarios where interfacial dynamics and capillary pressure relaxation play a significant role. This research addresses these challenges by leveraging the Thermodynamically Constrained Averaging Theory (TCAT) framework to develop a more fundamental approach to modeling two-phase fluid flow. TCAT systematically derives macroscale models from first principles, ensuring thermodynamic consistency across scales. The study focuses on the TCAT Constant Gas-Phase Pressure (CGP) model as an initial step toward implementing the full TCAT model. A suite of test problems was developed to evaluate the limitations of traditional models and validate the TCAT CGP model. The results demonstrate that traditional models struggle to capture essential physics in cases involving primary drainage, main imbibition, non-equilibrium capillary pressure, and complex displacement patterns with hysteresis and entrapment. The TCAT CGP model provides a more accurate and physically consistent alternative, particularly in capturing transient capillary pressure dynamics and interfacial interactions. Comparative analysis highlights TCAT’s potential as a more predictive and robust framework for modeling two-phase fluid flow. This work establishes the foundation for future research aimed at parameterizing the full TCAT model, extending implementations to multidimensional systems, and integrating TCAT into established simulation frameworks. By bridging microscale physics with macroscale applications, TCAT offers a transformative approach to advancing the modeling of two-fluid flow in porous media.Doctor of Philosoph
THE IMPACT OF THE LIFETIME FITNESS PROGRAM ON COLLEGE STUDENTS' FITNESS PROFILES
Get PDFThe transition to college often leads to declining physical activity with ~24% of students experiencing a marked decrease. This quasi-experimental study examined the Lifetime Fitness (LFIT) program’s impact on 1,936 undergraduate students’ fitness profiles at UNC Chapel Hill. Pre-post assessments measured changes in cardiorespiratory fitness, muscular endurance, and flexibility across various LFIT sections over 13-14 weeks. Results showed improvements across all fitness components: cardiorespiratory fitness improved 2.0% in resting heart rate and 3.0% in heart rate recovery, muscular endurance increased 14.3% for regular push-ups, 17.4% for modified push-ups, and 9.5% for sit-ups, while flexibility was enhanced 6.6% in sit-and-reach scores. Baseline fitness levels consistently predicted improvements across all components, with lower initial fitness associated with greater relative gains. These findings demonstrate that mandatory physical activity programs potentially improve multiple fitness components in college students, particularly those with lower baseline fitness, supporting university required physical activity as a public health strategy.Master of Art
Evaporating Exospheres in Young Planetary Systems & Interdisciplinary Outreach Programming in Informal Environments
Get PDFIn this dissertation, we examine two topics related to astronomical spectroscopy - an observationalastrophysics project analyzing spectroscopic data of three planetary systems, and an informal scienceeducation research project discussing the physics of light and photography. Each project is givenits own chapter, included with its own relevant background and introduction, methods, results, andconclusions. The first chapter provides a brief introduction to the overall thesis. In the second chapter, wediscuss our study of young exoplanets. Gaps in the exoplanet population, such as the NeptunianDesert, point to the importance of mass-loss in sculpting the radii of close-in exoplanets. Youngplanets (< 500 Myr) offer the opportunity to detect such mass-loss while it is still strong, andto test models of the underlying physical processes. We search for evidence of an Hα transit inhigh-resolution spectra of three young planets, HD 63433 b (400 Myr), DS Tuc A b (45 Myr), andHIP 67522 b (17 Myr). We validate our method by testing our method on several photospheric linesless impacted by stellar variability. We find no evidence of a transit signal for HD 63433 b andDS Tuc A b. For HIP 67522 b, we detect a significant depth change aligned with the transit time,blueshifted from the stellar rest frame by 21 km/s. Stellar variation in the Hα line over course ofthe observations is comparable in size to the transit signature and the duration is shorter than thephotometric transit, so this detection requires confirmation. Our findings, and other recent results inthe literature, suggest focusing on < 50 Myr systems for the detection of atmospheric escape. Following our discussion of exoplanets, we present our project on informal science educationfocused on science cafe style talks. Science cafes are informal public talks typically held at cafes,pubs, and breweries, offering experiences for the general public to learn more about science whileengaging directly with professional scientists, researchers, or educators. Science cafes aim to promotea greater scientific literacy for the general population by offering these educational talks at morecasual environments, such as breweries, coffee shops, and public libraries. While reaching a diverseaudience is a goal of most science cafe programs, there are few studies aimed at researching audiencediversity. From the studies that do exist, data suggests a lack of diversity at these programs, withattendees consisting primarily of white, college educated people. To test how an interdisciplinaryapproach might have an impact on audience diversity at science cafes, we devised a new program,Light, Cameras, Astronomy, that combines elements of art, history, and science to discuss photographyand its impacts in the arts and sciences. Thanks to its interdisciplinary nature, this program couldbe held a wide variety of locations to include museums, arts centers, and libraries. When we studyattendance at this new program, we find that audiences were typically more racially diverse, andcame from different educational backgrounds. This data suggests an interdisciplinary approach toscience cafe programming may improve audience diversity.Doctor of Philosoph
High Anxiety: The Long, Strange History of a Structure of Feeling
Get PDFWe live in anxious times. Everywhere we look there is something to be anxious about.Anxiety is so prevalent that it carries with it a feeling of inevitability. It feels like it is in the airwe breathe, ambient and inescapable. In this dissertation, I tell a different story about anxiety,one that shifts our perspective from the individualized, medicalized, and psychologized model ofmental health to the social/cultural level, examining anxiety as a structure of feeling. Structuresof feeling are embodied cultural atmospheres that shape how people feel their way through theworld. I work against what we think we know about anxiety and its history and relocate us withina long, strange history of discourses and struggles that articulate contemporary anxiety. Throughout history, anxiety and its articulations place me on significant moments ofhistorical transformation, moments in which the old is dying and the new cannot yet be born.Within these moments, we struggle over our taken for granted realities. These conjuncturalmoments organize my dissertation, taking me from the rise of “neurasthenia” to what I callpopular disaffection, self-regulating masochism, and precarity. Along the way, I argue thatanxiety as a structure of feeling exists within particular affective landscapes (grief, optimism,pessimism) and subsumes/articulates and is articulated by several other structures of feeling thatproduce a historically specific experiences of anxiety. These other structures of feeling, which Igenerally call individuation/narcissism, disaffection, and insecurity, articulate any number ofrelations and struggles in different conjunctural moments, allowing me to tease apart thespecificities of particular conjunctures and the articulations of anxiety as a structure of feeling.By bringing together the specificities of conjunctural formations and the political, economic,cultural, and intellectual contexts that shape those conjunctures, I argue that we can gain insightinto our histories so that we might once again begin to welcome the future and articulatestruggles that can bring about the more just and caring world for which so many of us long.Doctor of Philosoph
Active Objects, Imagination, and Devotional Practice in Late Medieval England
Get PDF“Active Objects, Imagination, and Devotional Practice” examines how objects exercised agency over humans in the late medieval period. By studying the contexts of the Sarum mass, the York Corpus Christi cycle, the Paris and London danse macabre, and books of hours, nonhuman agency is revealed through the ways that objects, spaces, and bodies prompt responses in human subjects. These responses take the form of physical actions, as well as imaginative experiences. From these imaginative experiences, late medieval people were moved to devotional acts, developing devotional practices that structured their ways of living in the world. Building on the material turn in anthropology and literary studies, my project argues that the late medieval period was acutely aware of material agency, an awareness that was leveraged to enhance Christian religious devotion by uncovering material networks of connection between objects, humans, and the divine. My work argues for a recovery of the lived religious experiences of late medieval people by turning to the material world that acted upon them as revealed through literature, art objects, and archival material. Ultimately, by understanding these medieval material connections, the active nonhuman agency of the world around us is revealed, opening up new possibilities of connection and how we define agency.Doctor of Philosoph
How Often Do Planetary Systems Form Misaligned?
Get PDFThere have been many recent discoveries of exoplanets whose orbital axes are significantly offset from the spin axes of their host stars. The existence of these misaligned planetary systems can generally be explained by one of two main mechanisms: either a planet forms from a misaligned protoplanetary disk, or the planetary orbit is perturbed by dynamical processes that occur after the planet has already formed. Traditionally, astronomers favored the second scenario, where planetary systems were predicted to form well-aligned like our Solar System, and any misalignments occurred post-formation. However, recent hydrodynamical simulations and sub-mm observations have shown that it is possible for disks to become misaligned from their hosts, and that the scenario of "primordial" misalignments of planetary systems may be more common than traditionally expected. In this dissertation, I present my work to measure the disk-star alignment distribution for a large population of systems with protoplanetary disks. Such work is challenging due to the difficulty in measuring the properties of young disk-bearing stars and the biases in the methods used to combine them for population analysis. I describe my efforts to measure precise properties of a wide range of young stars, including stars with protoplanetary disks. I present a methodology to combine star and disk properties to determine the statistical disk-star alignment distribution for a large population of systems. Lastly, I apply this methodology to a population of systems within the Ophiuchus molecular cloud and the Upper Scorpius OB association to determine how often primordial misalignments may occur in those regions.Doctor of Philosoph
RECRUITMENT COSTS AND WOMEN’S PERCEPTIONS OF CERVICAL CANCER SCREENING COSTS IN A TRIAL OF LOW-INCOME, UNDER-SCREENED WOMEN
Get PDFBoth in the US and globally, cervical cancer incidence and mortality occurs disproportionately in underserved populations. Women at the highest risk of cervical cancer, however, are frequently missed by screening programs. Mailed at-home HPV testing creates opportunities to increase screening access. Best practices to reach under-screened populations and overcome traditional screening barriers are needed to maximize utility of self-collected HPV-based screening. The objective of this dissertation was to provide essential information for interventions targeting high-risk populations, using MBMT-3 trial data. In Aim 1, we tallied trial recruitment methods material and staffing costs and calculated the cost per person eligible, enrolled, and screened in the trial. Of 898 eligible women, the majority (65%, n=579) heard about the trial through Craigslist, which had the lowest cost per eligible woman (34). Postcards/posters/ flyers (124) were also successful. In contrast, costs per enrollee were highest for email broadcast (1,275), and radio ads (10,400) and self-identifying as Black (postcards: 62%, bus: 76%). In Aim 2, we examined expected in-clinic screening costs as a potential screening barrier and compared expected to actual costs for control group participants. We explored differences between costs for Black and White participants to examine whether perceived financial barriers contribute to disparities. We found participants consistently overestimated screening costs; the median expected costs for participants completing screening was 5 for actual costs. While expected costs were higher for Black versus White participants (median 205, respectively), actual costs were similar. We find that Craigslist can be an effective and affordable outreach method for low-income, under-screened women, but using additional methods is important to ensure women of different socio-demographic backgrounds are reached. Outreach and educational interventions for existing affordable screening services may alleviate the impact of perceived costs as a barrier to cervical cancer screening, particularly for historically marginalized populations.Doctor of Public Healt
Low-metallicity Nova Explosions: A Site for Weak rp-process Nucleosynthesis
Get PDFClassical novae are common cataclysmic events involving a binary system of a white dwarf and a main-sequence or red giant companion star. In metal-poor environments, these explosions produce ejecta differently from their solar counterparts due to the accretion of subsolar-metallicity material onto the white dwarf. In particular, it has been suggested that the nucleosynthesis flow in such low-metallicity nova explosions extends up to the Cu–Zn region, much beyond the expected endpoint, around Ca, predicted for solar-metallicity classical novae. This behavior resembles a weak rp-process, and such nuclear activity has never been observed in accreting white dwarf binaries with typical accretion flows. In this work, we study the characteristics of the weak rp-process for four nova models with metallicities Z = 2 × 10−9, 10−7, 2 × 10−6, and 2 × 10−5, and explore the impact of the nuclear physics uncertainties via a Monte Carlo sensitivity study. We identify nuclear reactions whose uncertainties affect the production of intermediate-mass nuclei under these conditions. These reactions and relevant nuclear quantities are targets for measurements at stable or radioactive beam facilities to reduce their rate uncertainties