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A Study of First-Generation College Student's Career Identity Development
No full textThe purpose of this study was to understand the career identity development of recent college graduates who were first-generation college students. The study sought to understand how individuals made sense of their careers before, during, and after college, and the factors they saw as contributing to their career identity development. It also sought to understand whether, in their experience, recent graduates saw the college classroom as having contributed to their developing thoughts about the career path best fit to their interests, sense of self, and life situations.
The study was informed and guided by four conceptual frameworks: career identity, different ways to relate to one’s choice of career (as job, career, and/or calling), the college classroom, and narrative identity. The study consisted of 20 semi-structured interviews (up to two hours in length) with first-generation graduates within their first year after graduation; it proceeded through two phases. Phase A featured recruitment of two institutions of higher education as well as recruitment of study participants (9) one-year post-receipt of the bachelor’s degree. Phase B was added due to the need for a larger study sample. Design changes in Phase B included the following: 1) reduction of sample size (to 20, reduced from 30), 2) inclusion of an additional cohort of graduates (graduating a year later than those in Phase A, 3) effort to recruit a third institution (this was not viable and thus canceled), 4) offering of a $25 incentive to individuals who completed the interview, 5) use of social media for study participant recruitment, and 6) use of snowball sampling to further fill out the sample. Phase B resulted in the recruitment of an additional 11 participants thereby achieving the desired sample size of 20.
Data analysis yielded four propositions, summarized as follows: First, high school can offer pivotal experiences in the career identity development of first-generation college students. Second, parents can play a significant role in the career identity development of first-generation college students. Third, experiences in college such as coursework, interactions with professors, and internships or jobs can influence a first-generation college student’s career identity development. Finally, upon graduation, first-generation college students may look to advance in their careers, either by immersing themselves in jobs and/or by pursuing advanced degrees. These graduates also cited passion as a key criterion for good career choice.
Selected implications for policy and practice include the following: Implement career guidance as early as high school. Commit resources to the improvement of the content and quality of career guidance in college at all levels. Develop internship offerings, and inform students of the career development benefits of internship participation
Formative Evaluation of a Newly Implemented Global Ophthalmology Residency Program
No full textThere are currently 124 accredited ophthalmology programs in the United States. An internet-based search performed in the spring of 2022 revealed that over 20 of these programs have a global ophthalmology elective as part of their curriculum, and this number is steadily growing.
These programs vary by duration, global partnerships, faculty involvement, and various other factors. Countless studies have shown the critical necessity of students, residents, and faculty being adequately prepared to travel for medical programs overseas as well as the consequences of lack of preparation. However, few medical organizations have any formalized preparation guidelines and standards in place. In 2021, Yale Medical School implemented a new global elective program for their ophthalmology residents.
This study partnered with Yale, along with several different key stakeholder groups, to perform a formative evaluation of their elective program to identify expectations, reservations, challenges, and perceptions about residents working overseas. The study examined key factors such as pre-departure preparation, ethical challenges, and clinical training in low-resource settings, and highlighted best practices for program development. The findings offer guidance towards ensuring residents are well-equipped to contribute meaningfully to global eye care resident elective programs
Tuning Conductance in Single-Molecule Electronics
No full textThis thesis explores approaches to controlling electron transport, which is essential for enabling single-molecule electronics as functional electronic components. The dissertation is structured into five chapters, each exploring a different method for modulating the conductance of single-molecule electronics.
Chapter 1 introduces the fundamentals of single-molecule electronics, including key concepts and theoretical principles for understanding their electronic behavior. It also presents the scanning tunneling microscope-based break-junction (STM-BJ) technique as the experimental platform used in this study.
Chapter 2 investigates temperature-dependent conductance in oligo[n]phenylene molecular wires, where electron tunneling occurs coherently. Conventionally, coherent tunneling is considered temperature-independent process; however, this chapter explains how thermal energy affects dynamic molecular conformation, resulting in conductance variations. Specifically, experimental findings, supported by density functional theory (DFT) calculations, reveal that thermal energy induces enhanced dihedral planarization, leading to an increase in π-orbital coupling and electron tunneling probability.
Chapter 3 explores conductance tunability in redox-active and light-switchable single-molecule electronics using ferrocene-based molecular junctions. STM-BJ measurements show that the oxidized state of ferrocene forms a direct Fe-Au bond with Au electrode, leading to significantly higher conductance compared to junctions with additional chemical linkers such as thioethers.
Chapter 4 further validates the bonding mechanism between the metal center atom (M) of Group VIII metallocenes (M = Fe, Ru, and Os) and the Au electrode. It explores the formation of ferrocene-, ruthenocene- and osmocene-based single-molecule electronics using STM-BJ measurements. Experimental and theoretical results demonstrate that Group VIII metallocenes can directly bind to gold electrodes without chemical linkers, highlighting their potential for fabricating redox-active and high-conducting single-molecule devices.
Chapter 5 introduces an approach to enhancing conductance through enhancing antiaromaticity in thiophene-based one-dimensional topological insulators. Unlike typical molecules with exponential conductance decay, this thiophene-based diradical system exhibits length-enhanced conductance. Furthermore, modulating oxidation states through photochemical and electrochemical methods increases antiaromaticity, significantly enhancing conductance of single-molecule electronics.
This thesis presents diverse methods for modulating conductance in single-molecule electronics by introducing unique electron transport mechanisms, utilizing thermal, optical, chemical, and electrochemical approaches
The modularity of arithmetic generating series of special cycles on ₀()
Get PDFIn the late 1990s, Stephen S. Kudla initiated an influential program to study the special cycles on orthogonal and unitary Shimura varieties. A major conjecture is the modularity of generating series of special cycles. In this thesis we focus on the case of modular curve ₀() where is an arbitrary positive integer. We prove the modularity of the generating series of special cycles values in the arithmetic Chow groups.
For the generating series valued in the codimension 2 arithmetic Chow group, the modularity is proved by establishing the arithmetic Siegel–Weil formula on the modular curve ₀(), i.e., we relate the arithmetic degrees of special cycles on ₀() to the derivatives of Fourier coefficients of a genus 2 Eisenstein series. The identity is proved by combining “difference formulae” on both the geometric and analytic sides. When is odd and square-free, our work gives a different proof of the main results of Sankaran, Shi and Yang. For the generating series valued in the codimension 1 arithmetic Chow group, the modularity is proved by combining the known results in codimension 2 and analyzing the reduction to primes | of cusps of ₀(). This generalizes the previous work of Du and Yang
Pochitas: Mexican American Girlhood in Depression-era Texas
No full textWeaving threads of intellectual, cultural, and political history into a richly textured social history of Mexican American girlhood during the Great Depression, this dissertation offers the first book-length study of pre-WWII Mexican American girls’ history. The project describes how ethnic Mexican girls articulated a unique and heretofore unacknowledged vision of “Mexican American” culture and politics distinct from — and in some cases directly oppositional to — the political cultures of men’s ethnic Mexican leadership in Depression-era Texas.
Pochitas recovers this vision of Mexican American girls’ radical politics from a fragmentary archive of yearbooks, scrapbooks, photographs, receipts, English and Spanish-language newspapers, play scripts, children’s books, oral histories, menus, memoirs, choreography, censuses, city directories, and immigration and vital records, in addition to club organizational records like speeches, conference transcripts, meeting minutes, memos, correspondence, and case files.
The project identifies Mexican American girls’ radical politics expressed not just in the girls’ manifestos, speeches, organized labor actions, and rigorous, self-directed public affairs study programs but also in the choreography of their folk-dance expositions, the planning of their enchilada dinners, their choice of entertainment at their birthday parties, and in the contours of everyday life for working-class Mexican American girls at the height of the Great Depression.
The dissertation not only explores the local social geographies of Texas’s Depression-era “Mexican colonies,” but also tracks Mexican American girls’ broader entanglements with a transnational web of activists, scholars, and political organizations that stretched from New York City to Mexico City and beyond. Particularly when their work and leisure took them beyond the recognized limits of their ethnic communities, the project ultimately argues that girls represented a social and political vanguard of the pre-WWII “Mexican American generation.
Enhancing Adaptation to Sea Level Rise and Coastal Flooding in New York City
Get PDFNew York City, a major seaport and international financial center, has significant economic assets and populations potentially exposed to coastal flooding along its 837-kilometer-long shoreline. The New York Panel on Climate Change (NPCC, 2015, 2019; 2024), initially convened by Mayor Michael Bloomberg in 2008, provides advice to the city in strengthening its resiliency to future coastal storms in the face of globally rising sea level (over 4 mm/yr within the past decade vs a 3 mm/yr global average rise since the 1990s (IPCC, 2021).
Previously, the NPCC found a sea level rise (SLR) of 0.28–0.53 meters by the 2050s, 0.56 m–1.27 meters (25-75 percentile) and up to 1.9 meter (90th percentile), at the Battery, Manhattan by 2100, relative to 2000–2004. SLR could reach nearly 3 m by 2100, in the very low likelihood (<3%), extreme high ARIM (Antarctic Rapid Ice Melt) scenario, which assumes partial destabilization of West Antarctica by 2100 (NPCC, 2019, 2015). Updated sea level projections for New York City now show a mid-range sea level rise of 0.36-0.48 m by the 2050s, 0.64-0.99 m by the 2080s, and up to 1.5 m by 2100, relative to the revised baseline period, 1995-2014 (NPCC, 2024).
Monthly tidal flooding in low-elevation neighborhoods ringing Jamaica Bay and Queens and elsewhere in the city starting in the 2050s would become more widespread by 2100. By late 21st century, areas that previously experienced monthly tidal flooding in the 90th percentile NPCC (2019) SLR scenario could suffer daily, even permanent high tide flooding under a more extreme SLR scenario, such as ARIM. Future extreme high coastal flooding events upper end SLR scenarios could potentially compromise habitability. Similar flood hazards could affect other low-elevation waterfront communities elsewhere (Fig. 1).
Ongoing and proposed city initiatives tailored to neighborhood needs include engineering solutions such as strengthening raising bulkheads and seawalls, constructing local levees and storm surge barriers, enforcement of stricter building codes to reduce flood risk, and restoring wetlands and beach dunes. Additional recommendations include updating FEMA (Federal Emergency Management Agency) coastal flood zone mapping, continued collaboration with the NPCC to update and refine local climate change projections, and strengthen coastal defenses, while tailoring approaches to specific neighborhood needs. Adaptations include new City resiliency projects designed to augment both hard and soft coastal defenses, increase protection of critical infrastructure, enable more public access to the waterfront, and provide recreational opportunities
The Role of the Retrotransposon Derived Capsid Genes, PNMA1 and PNMA4, in Fertility Maintenance with Age
No full textAlmost half of the human genome consists of retrotransposons, ‘parasitic’ sequences that insert themselves into the host genome via an RNA intermediate. While most of these sequences are silenced or mutationally deactivated, they can present opportunities for evolutionary innovation: mutation of a deteriorating retrotransposon can result in a gene that provides a selective advantage to the host in a process termed domestication.
The PNMA family of gag-like capsid genes, which in humans includes at least eleven full-length genes—eight of which have clear homologs in mice— was domesticated from an ancient vertebrate retrotransposon of the Metaviridae clade at least 100 million years ago. Of this gene family, PNMA1 and PNMA4 are the two most highly expressed in gonads. PNMA1 and PNMA4 are also positively regulated by master germ cell transcription factors and their transcripts are bound by translational regulators in gametogenesis. This developmental regulation of PNMA1 and PNMA4 expression in gonadal tissue suggested to us that they might serve a reproductive function. However, while some retrotransposon derived genes (RDGs) have described roles in reproductive biology, the contribution of PNMA1 and PNMA4 to reproductive fitness and longevity was unknown.In this thesis I explore the role of PNMA1 and PNMA4 in reproduction.
In Chapter 1, I describe transposable element evolution and the domestication of these elements into novel genes with beneficial functions to their host. I investigate the evolution of the PNMA gene family, exploring their conservation, their known biological roles, and begin to describe their expression in gonads. The primary objective of this thesis is to examine the role of PNMA1 and PNMA4 in the gonads, but to do this it is critical to understand how these RDGs are controlled.
In Chapter 2, I focus on the control of PNMA1 and PNMA4 by host factors, exploring the role of DAZL in translational control of RDGs in HEK293T cells. I also investigate the ability of DAZL to control other factors to investigate the specificity of the translational control. I also test if other RNA-binding proteins have the capacity to bind and control PNMA1 and PNMA4 expression.
In Chapter 3, I explore how loss of Pnma1 and Pnma4 in mice could affect fertility with age. By conducting fertility assays, characterizing gonad health, and investigating gamete development in Pnma1-/-, Pnma4-/-, and Pnma1-/-; Pnma4-/- mice, I show that these Pnma knockout mice display a rapid onset of age-related subfertility leading to a lower degree of reproductive fitness versus wild type controls. I also show that these mouse lines show no neurological and behavioral defects, and I also characterize double heterozygous mice, which do not display a fertility defect.
In Chapter 4, I investigate the complex relationship between obesity, endocrine defects, and fertility. Here, I show that Pnma knockout mice have excess adipose accumulation despite not consuming more food than wild type controls. In chapter 5, I describe the capsid forming capacity of PNMA1 and PNMA4 proteins. I show purifications of these capsids from bacteria, with corresponding electron micrographs showing capsid formation and size. I also show purification of capsid-like structures from transfected human cells and from mouse testes.
Lastly, I show that in mouse testes, PNMA4 appears to package its own mRNA. Methods and final conclusions are detailed in Chapters 6 and 7, respectively. Together, the studies described in this thesis support the hypothesis that PNMA1 and PNMA4 support fertility maintenance with age
Interpretable Algorithms for Data Integration: Adaptivity, Contamination, High-dimensionality, and Privacy Constraints
No full textThis dissertation presents several methodological and theoretical contributions addressing modern challenges in data integration, with a focus on interpretable statistical approaches for tackling these issues.
We begin by introducing the motivation for studying data integration, along with illustrative examples. We then outline key challenges encountered by existing methods, including distributional shifts, data contamination and adversarial (Byzantine) attacks, high-dimensional settings, and privacy constraints. The subsequent chapters address these challenges by introducing new methods with provable theoretical guarantees across various contexts.
Our first contribution is a transfer learning algorithm tailored for high-dimensional generalized linear models, incorporating an aggregation step followed by a debiasing step. Building on this, we develop an inference procedure based on the debiased Lasso. We establish both finite-sample guarantees and asymptotic normality. In addition, we propose a transferable source detection method designed to identify and remove contaminated or anomalous datasets.
Next, we propose a federated Gradient-EM algorithm for parameter estimation in general mixture models. The method is designed to be privacy-preserving, computationally efficient, and adaptive to model similarity. We show that, under certain conditions, the algorithm achieves nearly minimax-optimal estimation error rates within polynomial time. Our theoretical results also extend to mis-clustering error bounds in specific mixture model settings, and offer insight into the empirical success of related EM algorithms proposed in the literature.
Finally, we introduce a representation learning framework for multi-task learning. Unlike prior work, our setting allows each task to have a distinct linear representation. We develop two algorithms for fitting this model via data integration, accommodating the presence of contaminated sources. One method is based on empirical risk minimization with a novel maximum principal angle penalty; the other leverages spectral methods. We derive both upper and lower bounds in finite samples, demonstrating near-optimal performance. The proposed framework generalizes prior models of linear representation and contributes several new theoretical and methodological insights
Thermoswitchable Hydrophilicity Solvents for Selective Mineral Recovery from Brines
No full textMany critical minerals for clean energy systems, such as lithium and rare earth elements, are present in industrial “waste” brines, including reverse osmosis concentrate and postflash geothermal brines. The selective extraction of minerals from these saline resources is critical for developing a sustainable supply chain.
This dissertation proposes a novel technology for selective ion separations using thermally switchable hydrophilicity solvents. Chapter 2 provides an overview of solvent-driven extraction processes, detailing state-of-the-art applications in desalination and zero liquid discharge. Gaps in our understanding of salt transport motivate further research into the behavior of ions in these systems. Chapter 3 combines computational chemistry with experimental studies to probe the molecular-level differences in salt partitioning between common monovalent cations and anions. Molecular dynamics simulations agree with experimental insightsinto water and solvent mutual solubility. However, simulations face limitations in capturing the partitioning of salt into switchable solvents, likely due to polarization and charge transfer effects.
Chapter 4 delves deeper into behavior of ions in water-solvent-salt ternary systems. The chapter investigates the properties of ions that govern partitioning into switchable solvents. Salt partitioning is shown to be highly ion-specific and its dependence on water co-extraction is quantitatively described by ion properties, most notable polarizability and charge density. Chapters 5 and 6 demonstrate that ion-specific partitioning persists in mixed electrolyte systems, enabling ion-selective separations. We establish a proof-of-concept for switchable solvent selective extraction (S3E) as a direct lithium extraction technology, achieving robust lithium/sodium and lithium/potassium selectivity and practical lithium recoveries.
Finally, Chapter 7 highlights the role of solvent structure in thermally switchable hydrophilicity. Trends in the temperature- and water-dependence of switchable solvents’ polarity are compared to macroscopic phase behavior, and comparative analysis of structurally isomeric solvents reveals significant performance differences. Overall, this dissertation advances the mechanistic understanding of salt transport in aqueous-organic biphasic systems and provides a foundation for the rational design of next-generation lithium extraction processes to promote a sustainable, circular economy for critical minerals
Costs analysis of integrating group interpersonal therapy into HIV care services in Senegal
Get PDFIntroduction
Group Interpersonal Therapy (IPT), an evidence-based treatment of depression recommended by the WHO mhGAP Intervention Guide, was implemented through a task-shifting approach in Senegal, as a treatment for depressed people living with HIV (PLWH). Since a description of the resources used and the implementation costs incurred is necessary to inform policymakers better, this study aimed to estimate the costs associated with its implementation.
Methods
Intervention costs were analyzed using an “ingredients-based costing approach” from the provider’s perspective. We identified and described the start-up and implementation costs for the initial phase and a projection over 5 years (implementation at capacity). We estimated total annual costs and cost per beneficiary. We conducted a scenario analysis to highlight some cost uncertainties and their impacts.
Results
The total annual costs were estimated at 8161 for the implementation at capacity. The training was the main cost driver representing approximately 60% of the total annual costs. The cost per beneficiary receiving group IPT was estimated at $65 for the implementation at capacity. The scenario analysis also illustrated the importance of parameters like the screening strategy, training activities, and allocation to cover transport costs mobilized by participants.
Conclusion
This cost analysis highlighted the costs and cost allocations required to implement group IPT in Senegal to treat depression in PLWH. This preliminary work should enable policymakers to identify the optimal resources to be mobilized to implement and ensure the sustainability of this therapy in HIV at a country-level program