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Assessing the Movement Ecology and Habitat Use of the Atlantic Guitarfish (Pseudobatos lentiginosus) in South Florida Using Acoustic Telemetry
No full textGuitarfish are a vulnerable and understudied group of ray species, and Florida is home to one species of guitarfish, the Atlantic Guitarfish (Pseudobatos lentiginosus). To date, fewer than ten studies have been published on Atlantic guitarfish, focused on their reproduction, feeding, mycobacteriosis, and vision. Many of these studies are >25 years old and offer limited information regarding the Atlantic guitarfish ecology. This project aims to fill knowledge gaps about the movement ecology and habitat use of Atlantic guitarfish. Throughout their range, Atlantic guitarfish encounter numerous threats, including commercial trawling, handline fishing, and gillnet fisheries, which target them directly or capture them incidentally as bycatch. Other threats include habitat loss and degradation from coastal development and oil exploration. As fishing effort in the Western Central Atlantic increases and populations of guitarfish face anthropogenic threats, it is important to address our lack of knowledge and expand research on this species. As part of this project, 28 individuals were located and captured via net using a roving diver survey off Palm Beach County and Broward County, FL, and internally implanted with acoustic tags to provide data on their movement patterns. Data were analyzed in R Studio to assess diel patterns, residency, and movement using both a coastal telemetry array and a fine-scale VPS array. Since there is no existing published information about the movement and habitat use of the Atlantic guitarfish, data from this study can inform fisheries management strategies and conservation efforts. </p
Power to the People: A Guide to Community-Based Initiatives
No full textThe term “community-based” has become a buzzword with organizations and individuals using the phrase as a self-proclaimed badge. Oftentimes, initiatives that have the intention of assisting a vulnerable population with a social problem further subject the community to being victims of the "system". Communities replete with social injustices are led to believe that institutions are outside of their influence. The powerlessness induced by this belief promotes the notion that individuals are destined by chance, thereby removing self-agency and initiative from the people. In this thesis, through the exploration of community-based supportive theories, power is found in the people. In order to adopt a community-based philosophy, initiatives must allow organizational operations to be fully guided by the community. Local knowledge and local control are paramount to community-based work. This work begins with communities defining themselves and utilizing individual and community realities to inform the direction of an initiative. Organizations are required to facilitate dialogue that interprets community members in the manner in which they wish to be understood. Dialogue serves as the foundation to understanding the needs and lived experiences of a community. Community-based instruments are explored and a critique of non-governmental organizations (NGOs) addresses the cardinal flaws of NGOs and the fundamental traits of community-based initiatives. This thesis concludes with an action-oriented call to become community-based.</p
TransAfroAmericas: Confronting and Debunking Myths of Whiteness in Brazil, the United States, and Colombia
No full textWith the formal abolition of slavery in the second half of the nineteenth century, white supremacy promoted several forms of racism in different parts of the Americas. In my dissertation, I look at the historical moment between the 1910s and 1950s, interweaving the works of three Black writers: Lima Barreto (1881-1922) from Brazil, Langston Hughes (1901-1967) from the United States, and Manuel Zapata Olivella (1920-2004) from Colombia. Drawing on Maurice Berger’s concept of “myths of whiteness” and Charles Mills’ idea of the racial contract, I examine how these authors used first-person narratives in colonial languages (Portuguese, English, and Spanish, respectively) to develop anti-colonial projects. To do so, I coin and develop the expression “TransAfroAmericas” to name the system of Black individuals that have challenged white supremacy in the “new world” since the sixteenth century. Within this system, I advocate for a multifaceted representation of race, developing the plural notion of “Blacknesses.” Based on an intersectional approach beyond the oft-studied constructions of gender, race, and class, I focus on three less-studied social markers: disability, sexuality, and nationality. In this reading, I consider the racialized components of the medical discourse of sanity and madness in Brazil, the white-based discourse of heteronormativity in the United States, and the exclusionary discourse of the American dream in Colombia. Thus, I analyze Barreto’s "Diário do hospício" written as a Black psychiatric patient institutionalized in an asylum, Hughes’ ambiguous expression of sexuality in his autobiographies "The Big Sea" and "I Wonder as I Wander," and Olivella’s accounts as a Black Colombian traveling in the United States in "He visto la noche.
Understanding Barriers and Decision-Making Pathways in Drug Addiction Treatment: A Community-Based Study on Black/African Americans in Miami-Dade County
No full textDrug addiction remains a significant public health concern, especially within Black communities in Miami-Dade County. Yet limited understanding of how individuals recognize addiction and decide to seek treatment restricts the development of culturally relevant interventions. This dissertation examines how Black adults in Miami-Dade County understand addiction, interpret their treatment experiences, and navigate pathways to recovery. Using a community-based and interpretive phenomenological approach, twenty-five participants were recruited through community and faith-based organizations in Liberty City and completed in-depth narrative interviews.Findings show that decisions to seek help were shaped by identity, family influence, spirituality, and experiences of stigma. Participants described addiction recognition as a personal and relational process that involved shifts in self-perception rather than clinical diagnoses. Treatment experiences varied widely. Some found support through compassionate, nonjudgmental relationships, while others encountered systems that felt impersonal, inflexible, or focused on insurance rather than care. Seven themes highlight the importance of belonging, trust, dignity, and active listening in supporting recovery.This study contributes to medical sociology by situating addiction within cultural and community contexts rather than viewing it solely as an individual or biomedical issue. It underscores the need for culturally responsive and community-driven approaches that center Black voices and experiences. By framing recovery as a lifelong and relational process, the study offers insight into how empathy, cultural understanding, and meaningful connections can strengthen pathways to treatment for marginalized populations.</p
The Story of Sickness: Improving Children’s Sick Face Perception
No full textChildren are vulnerable to disease, yet are poor at recognizing and avoiding sickness. We recruited 5- to 9-year-olds (N=120, 38% female, 60% White, 48% Hispanic/Latine) to test whether children’s sickness sensitivity is malleable and can be improved through training. Children randomly assigned to engage in a game-based disease training, compared to a control group, when trying to determine facial health, looked more equally at sick and healthy faces and reported using facial features of lassitude (e.g., drooping eyelids) more. The trained children also had higher disgust sensitivity and showed stronger sickness avoidance accuracy. However, we did not find strong evidence of younger children benefiting more from training than older children, as we hypothesized. These findings suggest that children’s sickness sensitivity may be malleable. Developing interventions for children’s pathogen avoidance, that account for the flexibility of children’s disease detection system, may reduce disease transmission and improve public health. </p
Leveraging Machine Learning Techniques to Accelerate Material Innovation in Civil Engineering Applications
No full textMany persistent challenges in civil and environmental engineering require innovative materials—such as creep-resistant cement for structural durability, materials that incorporate CO₂ into building components, and low-cost catalysts for water treatment. Traditional materials discovery is slow and costly, relying on trial-and-error. While physics-based computational methods improve understanding, they are resource-intensive and unsuited for high-throughput screening. Machine learning (ML) offers a powerful alternative, enabling efficient exploration of material properties and recognition of patterns beyond human capability.This thesis applies ML techniques to accelerate material innovation across three key areas:I. Creep Prediction in Disordered Solids: Using molecular dynamics and ML classification, we identify "looseness", a structural descriptor strongly correlated with early-stage creep in calcium-silicate-hydrate (C-S-H), guiding microstructural design.II. High-Entropy Alloy (HEA) Electrocatalysts: ML regression models trained on DFT data predict O* and HO* adsorption on CoFeNi-X (X = Mo, Mn, Cr) HEAs, enabling rapid screening and design for water treatment catalysts.III. Earth-Abundant Oxides for CO₂ Mineralization: Pre-trained ML models from the Open Catalyst Project are used to screen CO₂ adsorption on 21 metal oxides. MnO (2, -1, 2) and Ti₂O (1, 1, 0) with oxygen vacancies emerge as promising catalysts.By integrating ML with simulations and open databases, this thesis establishes predictive frameworks for rational material design, supporting advances in civil engineering and sustainable technologies.</p
ABCDs: Argentina, Bolivia, Courts, and Democracy
No full textThis research considers Argentina and Bolivia as exemplary case studies of how political court-packing, and the subsequently diminished rule of law, have eroded democratic safeguards.The purpose of an independent judiciary is not to be redundant on the legislative or the executive, but to be a guardrail. A democratized judiciary that is highly responsive to political whims is vulnerable to the institutional deterioration of unchecked populism, not a check on it. If we care about protecting democracy, we should also protect the independence of our courts to uphold the rule of law (at home, and throughout our hemisphere). Systemic attacks, including assaults on the integrity and personal safety of jurists, undercut judiciaries throughout our hemisphere and threaten critical norms and safeguards of liberal democracy.Sadly, the plague of this dangerous and erosive politics is not only limited to solely deteriorating the tissue of judicial integrity, but it also breeds corruption and enables political unaccountability. Efforts by dictators (and their authoritarian aspirants, alike) to weaken institutional norms and disable anti-authoritarian mechanisms have included coercion, threats, and court-packing — all to stifle the rule of law. Argentina’s Cristina Fernández de Kirchner and Bolivia’s Evo Morales have made these (and other) attacks against their national judiciaries; they have sought to reshape their judiciaries in Argentina and Bolivia into “kangarooed” rubber-stamps favoring their personal and partisan interests. Courts have been incapacitated to check or balance the authority of the other branches and have been contorted into complicity in abuses of power, infringing on due process and fundamental rights, and legislating from the bench.Kirchner’s and Morales’ forays into “court-packing” and other so-called judicial “reforms” provide case-studies and warnings of the potential consequences to democratic stability in our hemisphere if similar efforts to politicize, or otherwise erode, judicial independence are adopted.</p
Safety and Efficacy of a Pan-Caspase Inhibitor Combined with Therapeutic Hypothermia for Noise-Induced Inner Ear Injury
No full textNoise-induced hearing loss (NIHL) and noise-induced vestibular loss (NIVL) are major public health concerns that arise from a complex interplay of oxidative stress, glutamateexcitotoxicity, and apoptotic cell death, ultimately leading to irreversible damage to cochlear and vestibular structures. The basal turn of the cochlea and the saccule of the vestibular system are particularly susceptible to acoustic trauma due to their anatomical and embryological characteristics. Despite the growing incidence and life-altering consequences of NIHL and NIVL, there are currently no FDA-approved pharmacological treatments to prevent or mitigate this form of sensory degeneration. This study explores a novel therapeutic strategy centered on the post-exposure administration of Z-VAD-FMK, a broad-spectrum pan-caspase inhibitor known for its ability to block apoptotic pathways, and evaluates its potential alone and in combination with mild therapeutic hypothermia (MTH), a non-invasive intervention that reduces inflammation, oxidative stress, and synaptic degradation. We hypothesize that Z-VAD-FMK will preserve inner ear function by preventing cellular degeneration and that its combination with MTH will produce additive neuroprotective effects. To test this hypothesis, we conducted three specific aims: (1) evaluate the safety and efficacy of Z-VAD-FMK in preserving auditory and vestibular function in a rat model of noise trauma through ABRs, cVEMPs, immunohistochemistry, and protein analysis; (2) assess the additive benefit of combining Z-VAD-FMK with noninvasive, precisely controlled localized hypothermia, using a custom-designed fluorocarbon cooling system; and (3) determine the feasibility of delivering targeted cooling to human inner ear structures using non-invasive external devices in cadaveric specimens, with real-time temperature measurements validated by computational modeling. </p
Psychedelics, Cannabis, and Cancer: Prevalence, Association, and Trends from 2015-2022, Using a Nationally Representative Dataset of United States Older Adults
No full textClassic psychedelics and cannabis are at the forefront of emerging alternative therapies to mitigate cancer symptoms and comorbidities, yet their prevalence, patterns, and long-term effects among older adults remain unclear. This dissertation utilizes 2015–2022 National Survey on Drug Use and Health data to 1) examine trends in lifetime cannabis and psychedelic use among US adults aged ≥50 years, 2) assess variations by cancer history and type, and 3) investigate potential associations with prostate cancer.The first study estimates prevalence and trends in classic psychedelic, cannabis, and combined use (co-use) among adults with past, recent, or no cancer history, considering socio-demographics. Findings show increasing use, particularly among adults ≥65 and males, highlighting the need for further research into therapeutic intent, usage patterns, and integration into cancer care. The second study examines the prevalence of cannabis, classic psychedelic, and co-use among cancer patients by cancer type. Findings show similar cannabis use in cancer survivors (41.6%) and non-cancer individuals (42.6%, p=0.21), but lower psychedelic (11.6% vs. 12.9%, pThis dissertation is the first in the literature to report rising cannabis and psychedelic use among a population-based sample of older US cancer patients, highlighting type-specific trends and links to prostate cancer.</p
Vascular Contributions and Cerebral Microstructure in Ethnically Diverse Individuals with Varying Cognitive Status using Advanced Diffusion Magnetic Resonance Imaging
No full textDementia is a significant public health challenge, with research indicating greater risk in Hispanic adults. Macrostructural MRI studies suggest the vascular contribution to dementia may be more pronounced within the Hispanic population than the neurodegenerative. However, advanced diffusion MRI is sensitive and specific to brain microstructural integrity associated with cognitive decline and may better detect and characterize ethnic variation in MRI biomarkers of dementia. While advanced diffusion MRI has recently become implemented in clinical studies of brain health and dementia, there is insufficient representation of Hispanic individuals. This dissertation addresses this gap in literatures by using advanced diffusion MRI to better characterize brain microstructural integrity in an ethnically diverse cohort. We report ethnic variation in the relationship between brain microstructure and cognition and found the importance of these relationships varied by ethnicity within each sex group. A stronger association was found for advanced diffusion MRI metrics in the hippocampus in non-Hispanic adults, while the vascular contribution was suggested to be stronger in Hispanic participants. Furthermore, sex-specific analysis revealed microstructural integrity in the hippocampal, amygdala, and cerebral cortex were strongest in non-Hispanic women and Hispanic men, while the vascular contribution was more pronounced in Hispanic women. We also found advanced diffusion MRI models were sensitive and specific to detecting and characterizing this variation. This study adds to the literature by presenting a precision medicine approach to characterizing potential interventional biomarkers of dementia. Further research is encouraged to study these advanced diffusion MRI models in larger and more ethnically diverse cohorts for better outcomes for people of all backgrounds. </p