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Preparing for the Habitable Worlds Observatory: Spectropolarimetric Radiative Transfer Models of Terrestrial (Exo)planets
No full textThe next major step for the exoplanet community lies in the characterization of terrestrial exoplanets, especially when it comes to identifying biosignatures and determining the habitability of these worlds. In response to this, NASA has proposed the Habitable Worlds Observatory (HWO), with the primary goal of searching for and characterizing Earth-sized planets in the habitable zones (HZ) of their stars. However, current characterization strategies that only rely on the unpolarized flux from the planets lose some of the informational content of the observed light and therefore suffer from degeneracies in the calculated planetary parameters. The sensitivity of polarization to the micro- and macro-physical properties of a planet’s atmosphere and surface makes it an invaluable tool that will enhance the characterizations of these worlds. Having accurate theoretical models of terrestrial exoplanets, validated against observations of solar system planets with known properties, will be vital for assisting in these characterizations. In this dissertation, I explore the power of polarimetry in characterizing terrestrial exoplanets and demonstrate its effectiveness at distinguishing between habitable and non-habitable planetary scenarios. I performed the first benchmarking of two independent polarization-enabled radiative transfer (RT) codes, as well as conducted the first investigations of the changes in the Earth’s spectropolarimetric signatures across all four geologic eons. Additionally, as terrestrial exoplanets are expected to be heterogeneous like the Earth, I analyzed the effects of time-variable features such as diurnal rotation, seasonal weather patterns, and different surface configurations on the resulting spectropolarimetric signatures of Earth and early Mars. With these models, I provided preliminary observing constraints for differentiating the habitable and non-habitable planetary scenarios with the HWO. Finally, as advanced telescopes will soon necessitate distinguishing habitable and non-habitable HZ planets, I used RT models to assist with characterizing new ground based observations of the polarized reflected light from Earth’s non-habitable twin Venus
Supervised Topic Modeling for Scientific Texts: Bayesian Shrinkage Methods and Domain-Specific Applications in Forensics and Online Aggression Sciences
No full textTopic modeling has become a powerful tool for analyzing large-scale textual corpora across scientific domains. However, traditional unsupervised approaches like Latent Dirichlet Allocation (LDA) often produce redundant or weakly informative topics, limiting their interpretability and predictive utility. This dissertation presents a dual-track study that advances the field of interpretable topic modeling and domain-specific text analysis by (1) quantitatively analyzing research trends in Cyber Aggression and Abuse (CAA), and (2) developing a supervised topic selection framework for forensic science literature.
In the first part, we apply LDA to a corpus of 2,309 journal abstracts on CAA sourced from the Web of Science database. This study is among the first to systematically map latent themes in CAA literature, uncovering hot and cold topic clusters, regional publication trends, and temporal shifts in research focus. Key themes include psychological impacts, identity-based harms, detection techniques, and digital interventions. Our findings highlight an evolving interdisciplinary landscape, offering novel insights for scholars, practitioners, and policymakers working on online harm mitigation.
In the second part, we introduce a supervised topic refinement method that integrates LDA with the Mixed-type Multivariate Bayesian Shrinkage Prior (Mt-MBSP) model. We apply this framework to thousands of forensic science abstracts published in the Journal of Forensic Sciences (2009–2022), aiming to identify a sparse, semantically coherent, and domain-relevant set of topics. Mt-MBSP leverages document-category labels to prioritize predictive topics, outperforming unsupervised baselines such as BERTopic in coherence and diversity metrics. We further validate the selected topics through classification experiments and theoretical generalization analysis using VC-dimension bounds, confirming their practical and statistical utility.
Together, these contributions offer a robust framework for interpretable and predictive topic modeling in applied scientific domains. Our work advances both the methodological landscape of topic selection and the empirical understanding of research trajectories in forensic science and CAA detection
Morphology, Evolution and Host-Driven Convergence in Ichneumonidae (Hymenoptera, Ichneumonoidea)
No full textUnderstanding the functional and evolutionary significance of morphology is fundamental to interpreting the tree of life. In recent years, emerging tools have enabled broad-scale analysis of discrete morphological data and facilitated the study of entire phenomes, helping to re-establish morphology as a central component of evolutionary research. These advances allow us not only to examine individual traits in detail but also to compare them across taxa and explore their evolutionary trajectories. This approach is particularly critical when studying hyperdiverse groups that exhibit both high levels of morphological convergence and complex life cycles intricately tied to host use. A prime example is the Ichneumonidae – the most species-rich family of parasitoid wasps – which presents an ideal model for such investigations due to their extraordinary species diversity, broad range of host associations, diverse life history strategies, and repeated convergent adaptations for host exploitation. However, to draw meaningful inferences about phenome evolution, several foundational components are required: (1) characters must be clearly defined and rigorously reviewed, (2) character statements should be supported by a standardized ontology to ensure consistency and comparability, and (3) a robust, preferably time-calibrated phylogeny must be available. While important advances have been made in each of these areas over the years, key limitations remain for Ichneumonidae – particularly in terms of comprehensive character definitions, standardized terminology, and the availability of a robust, time-calibrated phylogeny. My thesis responds to these limitations with the overarching aim of understanding morphology and its role in the evolution of parasitoid wasps. By addressing key knowledge gaps and developing tools that strengthen the morphological foundation for evolutionary research, this work helps establish a more complete framework for broad-scale evolutionary analyses. To achieve this, I integrate diverse morphological systems and analytical approaches. In Chapter 2, I develop a standardized terminology for male genitalia in Ichneumonoidea, aligning legacy terminology with the Hymenoptera Anatomy Ontology to improve clarity and interoperability. In Chapter 3, I investigate ovipositor morphology and describe a novel steering mechanism for host localization, including the discovery of a sclerite fuctionally equivalent to the furcula in Aculeata. In Chapter 4, I examine multi-trait convergent syndromes associated with parasitoids of wood-boring hosts, providing new insights into the repeated evolution of functionally similar morphologies. In Chapter 5, I assess evolutionary rate variation across a time-calibrated phylogeny to test whether major transitions in host use correlate with shifts in the tempo of morphological evolution. This dissertation deepens our understanding of the morphological innovations and constraints shaping Ichneumonidae evolution by uncovering novel traits, standardizing terminology, and linking host use to evolutionary rate shifts—laying the foundation for comparative phenomic research in parasitoid wasps
Decreasing Administrative Burdens For Promoting Social Equity: Three Essays On Innvations In Public Service Provision
No full textThis dissertation investigates three aspects of administrative burdens in public service delivery and explores how these burdens—which often discourage eligible individuals from accessing needed services—relate to individuals\u27 perceptions of and behaviors toward those burdens and ultimately to user outcomes. The first essay examines whether a shift from in-person to virtual service modalities imposes additional administrative burden—digital administrative burden—for service users. Using the secondary data from the 2022 “Survey of Citizens’ Perceptions of Public Administration” conducted in South Korea, the study applies Coarsened Exact Matching (CEM) to assess the relationship between service modality and digital administrative burden. The findings suggest no significant difference in administrative burden between those who accessed services virtually or those who accessed them in person. The second essay explores whether demographic congruence—specifically gender and race congruence—between service providers and service users reduces psychological burdens during the service process. Focusing on people experiencing homelessness (PEH), this study uses Homeless Management Information System (HMIS) data and responses to the Vulnerability Index-Service Prioritization Decision Assistance Tool (VI-SDPAT). A two-stage least squares (2SLS) estimator reveals that gender congruence unexpectedly increases psychological costs, while race congruence reduces them and fosters users’ cooperation. The third essay analyzes whether task integration across multiple service organizations improves user outcomes. Utilizing secondary data from the Korean Youth Panel (2016-2020), the study evaluates the Employment and Welfare Plus Center (EWPC), a government initiative designed to provide integrated services, using a two-way fixed effects (TWFE) estimator. Contrary to expectations, the analysis finds task integration is negatively associated with users’ outcomes. Together, these studies offer insights into the complex nature of administrative burden in public service delivery. The findings underscore the importance of tailoring interventions to specific populations and service environments and call for continued research to advance equitable and effective service provision
Project Esperanza: A Pilot Study on Isolation, Belonging, and Hope for First-Generation Latinx College Students
No full textThis study is a two-part manuscript dissertation that explores and assesses culturally grounded strategies to best support first-generation Latinx college students (FGLCS), who often face unique academic and psychosocial challenges. The first manuscript is a conceptual exploration of the intersecting constructs of social isolation, belonging, and hope, and their impact on the well-being and academic success of FGLCS. Thematic analysis revealed the importance of mentorship, culturally relevant content, and opportunities for reflection and community-building. These findings informed the development of a psychoeducational intervention, Project Esperanza. The second manuscript introduces the pilot study designed to reduce social isolation and enhance belonging and hope among FGLCS. Using a quasi-experimental single-group pretest-posttest design, 39 participants completed surveys assessing isolation, belonging, and hope before and after the intervention. Results indicated a meaningful reduction in social isolation (d = 0.45), while changes in hope and belonging reflected small effects. Correlational analyses also revealed important associations between isolation, ethnic identity, and mental health indicators. Together, these findings suggest that culturally grounded, community-based interventions like Project Esperanza may effectively reduce isolation and foster connection among FGLCS, which can, in turn, support student retention and academic success. Implications for counselor education, student support services, and future research are discussed
The Association between the Social determinants of health and Shared decision making: An Investigation of the National Survey of Children\u27s Health
No full textObjective: Shared decision-making (SDM) is defined as a clinical approach that allows both physicians and patients to communicate on the best treatment options that will improve the patient\u27s overall health outcomes. Shared decision-making plays a vital role in how parents engage with their physicians regarding the healthcare needs of their children. This dissertation assessed the association between the social determinants of health and shared decision-making regarding children’s health-related issues.
Methods: The data for the current research were the National Survey of Children’s Health (NSCH), combined 2017-2020. The dependent variable was shared decision-making and included discussing treatment options, raising concerns regarding recommendations for care, and working together on choices for treatment. The main independent variable was social determinants of health and included economic stability, neighborhood built and environment, educational access and quality, health care access and quality. The researcher analyzed sample characteristics, and estimated logistic regression to make valid conclusions in answering the research question, how are various social determinants of health associated with different types of shared decision-making regarding children’s health related issue?
Results: Approximately 70% of respondents engaged in at least one type of shared decision making. Several social determinants of health such as family resilience, safe neighborhoods, English language, higher education, private health insurance, health care visits, and alternative health care visit were associated with more shared decision making, compared to economic instability, adverse childhood experience, trouble paying medical bills, health insurance type, and special education associated with less shared decision makin
Making Sense of the Role of ChatGPT in Education: An Examination of Student Views in China, Italy, Kenya, Uruguay, and the U.S.
No full textThis article investigates the diffusion and adoption of ChatGPT among college students from a multinational convenience sample, informed by the scholarly literature on the diffusion and progressive appropriation of ChatGPT by students and teachers within the education sector and the strategies adopted by academic institutions. We applied a figurational approach to this study, offering two theses that try to understand the societal meaning of ChatGPT diffusion in the educational sector. Operationally, we explored university students’ behavioral intentions, practices of use, and opinions toward ChatGPT in five countries (China, Italy, Kenya, Uruguay, and the United States of America) through an online survey. Results indicated that: (1) students seem to be cautious or resist the hype of generative intelligence; (2) an essential cultural pattern emerges: American and Italian students are more pessimistic toward ChatGPT, whereas Chinese students, sometimes accompanied by Kenyan and Uruguayans students, are more optimistic; (3) men and techno-scientific students are more positive toward ChatGPT than women and socio-humanistic students
Disentangling (Hybrid) Trustworthiness of Communicative Generative AI as Intermediary for Science-related Information—Results from a Qualitative Interview Study
No full textThe increasing prevalence of communicative Generative AI, such as ChatGPT, highlights their transformative potential for science communication while raising critical questions about users’ trust in these systems conveying science-related information. As perceptual hybrids these agents challenge traditional notions of trustworthiness, and it remains unclear to whom or what users refer to as the object of trust. This qualitative interview study integrates dimensions from human-machine and epistemic trustworthiness within a hybrid framework, complemented by a descriptive source orientation model. It highlights that trustworthiness assessments can extend beyond a chatbot’s interface, emphasizing the perceived salience of its underlying infrastructure, developers, and organizations. By exploring the multifaceted nature of trustworthiness, the study offers a theoretical and empirical contribution to understand how diverse layers contribute to users’ trustworthiness perceptions, particularly in the context of science-related information seeking
Episode 72: Liliana Ramos - TEFL Certificate, Fulbright ETA Spain & EPIK Program
No full textIn this episode, we catch up with Liliana Ramos after her Fulbright ETAship in Logroño, Spain. Liliana is a returning podcast guest who finished a TEFL certificate in our department while completing her undergraduate degree in International Relations. Hear her share takeaways from her time in Spain and talk about her transition to her latest adventure: teaching with the EPIK program in Wonju, South Korea. Liliana highlights the cultural immersion, personal growth, and the supportive community in both programs. She talks about how to prepare for working abroad and about the transformative education which is a part of these experiences.
This episode was recorded in summer 2025
Love Serving Autism
No full textThe organization we chose for our project is Love Serving Autism, a nonprofit dedicated to empowering individuals with autism and other developmental disabilities through the sport of tennis. This program helps participants grow both physically and mentally while fostering social interaction and inclusion. Many of these children may not otherwise have the opportunity to participate in sports or engage in consistent physical activity.
Through Love Serving Autism, they can play tennis and connect with volunteers in a supportive, welcoming environment each week with no charge of cost.
Our team worked with about twenty kids weekly, and the experience was truly eye-opening— reminding us how powerful sports can be in creating equal opportunities and bringing people together.https://stars.library.ucf.edu/hip-2025fall/1012/thumbnail.jp