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TheSelf, Life, and the Arts of Living: An Approach to Foucault’s History of Subjectivity in Greco-Roman Antiquity
No full textThesis advisor: James BernauerFoucault’s late works examine how we develop relationships with ourselves that involve, at the same time, an ethical approach and a relationship with truth. His historical studies address this problem in Mediterranean antiquity and notably include the last three volumes of his History of Sexuality and the lecture courses Subjectivity and Truth, The Hermeneutics of the Subject, and The Courage of Truth, among others. Within those works, this dissertation analyzes different historical ways to approach the self from a moral perspective and, in particular, the concepts that define the self or its elements. Here, I unearth a crucial, recurrent, and understudied tension in late Foucault’s historical works between two moral emphases on the relationship with oneself. One is an outward focus on our life—what we do and our engagement with others and the world. The other is an inward focus on our soul. This perspective tends to privilege self-knowledge, advocate for converting the self to its right state, and adopt a universalist approach independent of individual circumstances. In his historical studies, Foucault finds that, in the transition from Classical Greece to the first two centuries of the Roman Empire to early Christian thought, there is a shift of focus from life to the soul. However, those opposing emphases are already present in Plato. My dissertation tracks these findings and the evolution of Foucault’s views in some of his major works from 1981 to 1984. I observe that their historical and philosophical sophistication increases in each work.My detailed analysis of Foucault’s historical research also offers a clearer understanding of his own philosophical views. Secondary literature often mentions the importance in his thought of the concept of the care of the self. This approach is too general because it does not consider the difference between the inward and outward focuses on the self. I argue that Foucault prefers an outward focus that emphasizes life. In other words, he advocates for life taking care of itself over the soul taking care of itself. This dissertation also conducts a historical and philosophical analysis of the concept of the arts of living in Foucault’s work. Compared to the related notion of the techniques or practices of the self, secondary literature has not extensively studied the arts of living. However, I argue this notion is crucial in both Foucault’s historical research and his philosophical proposals for the present. Unlike the more general concept of the care of the self, Foucault considers that the art of living is pertinent in his present, including for philosophy, sexual minorities, and general ethical purposes. Finally, this dissertation takes distance from the secondary literature that emphasizes the affinity between Foucault’s thought and Stoicism. I suggest that, in his view, Stoicism takes an inward perspective of the self, which, compared to Classical Greece, increases the universality of morality and the need for individual self-knowledge. In this sense, Stoicism moves Greco-Roman morality in the direction of Christianity. Stoicism also proposes conversion—taking the self to its right state and keeping it there. In contrast, Foucault advocates for a non-universalist morality and, regarding the self, proposes to maintain an outward perspective of it and constantly disturb it.Thesis (PhD) — Boston College, 2024.Submitted to: Boston College. Graduate School of Arts and Sciences.Discipline: Philosophy
Unraveling Transcriptional Regulatory Networks in Toxoplasma gondii: Insights into Cell Division and Extracellular Stress Response
No full textThesis advisor: Marc-Jan GubbelsThesis advisor: Sarah McMenaminToxoplasma gondii, an obligate intracellular parasite, infects nearly one-third of the global population, causing the disease toxoplasmosis. Despite its significant health impact, the molecular mechanisms governing its lytic cycle and stress-induced adaptation remain incompletely understood. The unique asexual cell division mechanism, endodyogeny, used by T. gondii to expand its parasitic biomass in intermediate hosts, including humans, leads to severe pathological consequences through repeated rounds of the lytic cycle, resulting in acute toxoplasmosis. The parasite’s cell cycle is characterized by a prolonged G1 phase, with centrosome duplication marking the onset of the S phase, followed by a transient G2 phase and a near-simultaneous onset of mitosis and cytokinesis. These overlapping division processes, coupled with the challenges of synchronizing T. gondii, obscure the precise molecular mechanisms of its transcriptional programs. To address these challenges, we employed single-cell RNA sequencing (scRNA-seq) and single-cell ATAC sequencing (scATAC-seq), combined with advanced machine learning tools, to reveal ‘transition points’ in gene expression and chromatin accessibility that correspond to shifts in biological activity during the lytic cycle. RNA velocity and time-course clustering analyses uncovered a significant G1a transcriptional burst and identified specific AP2 family transcription factors (TFs) that peak during the C-to-G1a transition, likely driving this burst to regulate G1 progression.
Further, we conducted an in-depth functional characterization of G1-specific TFs, focusing on AP2XII-8, which plays a critical role in activating a ribosome regulon to promote G1 progression. The study identified combinatorial binding motifs and suggested the existence of a large AP2XII-8 protein complex, involving other TFs and epigenetic factors, that reuglates the intricate processes of T. gondii cell cycle replication. Additionally, we examined stress-responsive AP2 TFs associated with enhanced virulence during in vitro evolution, providing insights into adaptive mechanisms that enable T. gondii to thrive under extracellular stress conditions.
Collectively, these findings enhance our understanding of T. gondii’s complex regulatory networks, offering potential targets for therapeutic intervention against acute toxoplasmosis. This dissertation provides the time-resolved transcriptional and chromatin accessibility landscapes of T. gondii’s lytic cycle, resolves transcriptional programs to DNA motifs, and identifies key regulatory elements involved in its cell cycle progression and stress response.Thesis (PhD) — Boston College, 2024.Submitted to: Boston College. Graduate School of Arts and Sciences.Discipline: Biology
Multilevel Factors Associated with Intent to Leave in U.S. Nursing Home Nurses:
No full textThesis advisor: Karen S. LyonsBackground: Intention to leave (ITL) is a prognostic factor of nurse turnover. High nursing turnover is associated with poor patient outcomes. Declining nursing home nurse retention is at a crisis level and requires immediate solutions especially with the predicted increase in nursing home residents. Registered nurses (RNs) working in the hospital setting are most often studied in ITL research; however, nursing home nurses have received little scholarly attention. Nursing homes differ in population served, nursing licensure type and ratio, and chronic disease management. Thus, it is possible that ITL factors may be different in nursing home nurses. Design: A retrospective cross-sectional design utilized the United States 2020 and 2022 National Nursing Workforce Surveys.
Purpose: To examine nurse factors associated with intent to leave among a population-based sample of United States nursing home nurses.
Method: Nurse respondent inclusion criteria included: (1) currently employed, staff nurse primary nursing practice, and the majority of time providing direct care, (2) age 18-56, and (3) primary setting self-identified as nursing home or extended care. A binary logistic regression model was used to assess the impact of several factors (age, gender, race, ethnicity, highest level of nursing education, tenure, work status (part-time or full- time), opportunity elsewhere, and COVID-19 impact. To examine if nursing home nurse ITL factors are different between licensed practical nurses/licensed vocational nurses (LPN/LVNs) and RNs, the binary logistic regression model was repeated with selected LPN/LVNs and RNs cases. Qualitative content analysis was utilized to examine stress experience in the nursing home workplace during the COVID-19 pandemic.
Results: Nurse factors that were statistical significantly associated with increased likelihood of reporting ITL were age, ethnicity, race, tenure, and salary. Factors with statistically significant associations of less likely to report ITL included gender, race, salary, work status, increased workload, and changed work setting. This study found certain nursing home nurse ITL factors are opposite from previously researched hospital nurse ITL factors. These factors included age, ethnicity, race, tenure, workload, and highest nursing education. There were also unique ITL factors depending on nurse license type. Preliminary evaluation of qualitative comments on workplace stress response in nursing homes indicates that further evaluation is needed in both respondent number and longitudinally.
Conclusions: Gaining knowledge of ITL factors in U. S. nursing homes informs practice, policy, nursing education, and theory. This study addressed a knowledge gap in nursing home nurse ITL. It is currently the sole study of nursing home nurse ITL utilizing a large nurse population-based sample. Knowledge of factors associated with ITL in nursing home nurses would assist with targeted recruitment and retention strategies.Thesis (PhD) — Boston College, 2024.Submitted to: Boston College. Connell School of Nursing.Discipline: Nursing
Multi-Level Modeling of Complex Systems: Mg-Based Energy Storage, Ribosomal Dynamics, and Beyond
No full textThesis advisor: Udayan MohantyThesis advisor: Junwei BaoThis dissertation presents the development and application of advanced theoretical techniques to address important challenges in complex biological and materials systems. We begin by investigating ion transport in metal-organic frameworks (MOFs), focusing on magnesium ion conduction in Mg-MOF-74 thin films. A novel computational approach is developed to model ion transport in the bulk MOF structure and at grain boundaries in an integrated manner. Through this, we identify strong binding at grain boundaries to be a limiting factor for magnesium ion conductivity in MOF. Next, we explore large-scale conformational rearrangements of the bacterial ribosome during protein synthesis. Molecular dynamics (MD) simulations are utilized to characterize physical pathways and energetic barriers associated with aminoacyl-tRNA accommodation, providing insight into the mechanism of tRNA proofreading by the ribosome. The dissertation also reports on the development of a quantum mechanical implicit solvation model for periodic systems, suitable for applications involving surface chemistry and crystalline materials. The developed model demonstrates significantly improved accuracy over previous methods and successfully predicts solvation effects in a wide range of molecular and surface systems. Finally, high-level theoretical calculations are employed to study the chemistry of polysulfides in magnesium-sulfur batteries. Our effort not only improves the fundamental understanding of magnesium polysulfide behavior but also lays new foundations for optimizing battery system design. Overall, this dissertation provides new tools for the development of next-generation energy storage technologies, sheds light on the elaborate mechanisms underlying fundamental biological processes, and advances the state of the art in solvation modeling for quantum chemistry calculations.Thesis (PhD) — Boston College, 2024.Submitted to: Boston College. Graduate School of Arts and Sciences.Discipline: Chemistry
Geometry Optimization and Modeling of Complex Molecules: Polypeptides, Protein Interactions, and Metal Oxide Surface Models
No full textThesis advisor: Junwei BaoThe mysteries in chemistry could be reveals by utilization of innovative computational methods and the creative application of advanced modeling techniques. The limitation or difficulties of experimental methods sometimes makes it hard to study the mechanism behind the reaction energy, so computational chemistry could play an important role to investigate and analyze the detailed reaction mechanism and elementary reaction pathways behind a complexed, multi-step chemical reaction. Also, it is important to develop robust and accurate theoretical methods to perform computational and simulation works. We applied multiple computational or simulation models to study various chemical systems, which provided us valuable insights to understand the chemical reactions happened in our daily life.
Chapter 1 explores an advanced Gaussian Process (GP)-based optimization approach for the efficient geometry optimization of polypeptides, focusing on reducing computational costs associated with single-point energy (SPE) evaluations in traditional methods. By employing Gaussian Process Regression (GPR) as a surrogate model, the optimization steps are minimized through a surrogate potential energy surface (PES) generated from quantum mechanical data. The study assesses the performance of four kernel types—Matern, squared exponential, rational quadratic, and periodic—within multiple coordinate frameworks, including redundant and non-redundant internal coordinates and Coulombic coordinates. Results indicate that the periodic kernel combined with non-redundant delocalized internal coordinates is the most effective in reducing optimization steps, particularly suited to handle molecular structures with periodic characteristics. Additionally, the rational quadratic kernel shows promise when used with Coulombic coordinates, offering flexibility for functions with varying smoothness. Implemented in the mad-GP framework, this study provides insights into optimizing large biomolecules, such as polypeptides, with significant implications for computational chemistry and biomolecular modeling. We also compared the GP-optimized structures with the AlphaFold-predicted structures to assess their respective effectiveness in accurate structure prediction. This comparison provides insight into the reliability and applicability of each method for modeling polypeptide conformations.
Chapter 2 investigates the interaction energies and energy decomposition of van der Waals (vdW) complexes between N6-methyladenosine (m6A) and tryptophan residues in YTH proteins, the readers of m6A modifications on mRNA. Given the role of m6A in cellular processes, structural insights into its interaction with YTH proteins could facilitate therapeutic advancements. We examined the effects of various chemical modifications on tryptophan residues (W465 and W470) in the YTH binding pocket, with the aim of enhancing the CH-π interactions with m6A through modified electron density. Using Density Functional Theory (DFT) and Symmetry-Adapted Perturbation Theory (SAPT), we explored the vdW interactions into electrostatic, dispersion, induction, and Pauli exchange components and identified London dispersion and electrostatics as dominant stabilizing forces. Correlations of these components with molecular descriptors such as polarizability and multipole moments further highlighted the effects of electronic properties on binding. Our results suggest that optimized tryptophan modifications could strengthen m6A recognition, potentially guiding the design of enhanced m6A-binding proteins for applications in RNA biology.
Chapter 3 presents a computational analysis of reaction pathways and energy barriers on LiCoO₂ and TiO₂ surface models, exploring their role in promoting reactions critical to lithium-ion battery (LIB) performance and catalytic applications. For LiCoO₂, we examine the dissociation of H₂O₂. Using density functional theory (DFT) and climbing-image nudged elastic band (CI-NEB) calculations, we identified and characterized the elementary steps in the dissociation mechanism, and indicated that the reaction barriers are reduced in the presence of organic species. For TiO₂, we model the adsorption and dissociation of a Li(DME)₃ complex, exploring solvent dissociation and solvent exchange mechanisms in the context of DME ligands. Results show that the TiO₂ surface aids in stabilizing Li⁺ ions after solvent dissociation, and it favors a solvent-exchange pathway with a lower reaction barrier. These insights provide valuable mechanistic detail that help the design of materials.Thesis (MS) — Boston College, 2024.Submitted to: Boston College. Graduate School of Arts and Sciences.Discipline: Chemistry
Social Determinants and Biosocial Consequences of Depressive Symptoms: Analyzing Social Capital, Depression, and Cognition in Later Life
No full textThesis advisor: Sara M. MoormanThis dissertation explores the complex relationship between social capital and depressive symptoms across the life course, focusing particularly on the increasing prevalence of depression from mid-to-late life. Using a life course perspective, this research investigates how social determinants, such as social capital, shape the emergence, increase, and decrease of depressive symptoms as individuals age. Drawing from both the tangible and psychological dimensions of social capital, this dissertation examines how changes in social connections and networks influence depressive symptom outcomes, including the biosocial consequences of depression on cognitive function in later life. The research is divided into three analytical papers. The first paper analyzes longitudinal data to assess the association between social capital and depressive symptoms, distinguishing between within- and between-person effects. The second paper explores how depressive symptom subtypes evolve from midlife to later life, identifying distinct subtypes and examining the stability and transitions between them over time. The third paper investigates the relationship between depressive symptom subtypes, social capital, and cognitive function, exploring how depressive symptom subtypes may mediate this association. Findings across these studies emphasize the pivotal role of social capital in shaping depression outcomes, highlighting how social isolation and disconnection may exacerbate depressive symptoms in later life. This dissertation contributes to the sociology of mental health and aging by offering new insights into the social mechanisms underlying depression and its long-term impacts on cognitive function. Through this work, policymakers and health professionals may gain a deeper understanding of how targeted interventions aimed at enhancing social capital could mitigate the global burden of depression in aging populations.Thesis (PhD) — Boston College, 2024.Submitted to: Boston College. Graduate School of Arts and Sciences.Discipline: Sociology
Enantioselective Synthesis of Tertiary Boronic Esters Through Conjunctive Cross-Coupling and Cyclobutene Diboration:
No full textThesis advisor: Marc M. SnapperThesis advisor: James J. MorkenThis dissertation will present three main projects focusing on the catalytic enantioselective synthesis and stereospecific functionalization of tertiary alkylboronates. In the first project, acyl chlorides were incorporated as a new class of electrophile in conjunctive cross-coupling, from which, a variety of tertiary β-boryl amides were successfully synthesized with high enantioselectivity. The utility of the tertiary alkylboronates products was also demonstrated through several orthogonal functionalizations of the boronic ester group and amide groups. The project culminated in the enantioselective total synthesis of natural product (+)-adalinine that leveraged this newly developed methodology. In the second project, a conjunctive cross-coupling enabled ring closure was developed to synthesize tertiary alkylboronates residing on carbocyclic and heterocyclic scaffolds. A Phosphinooxazoline (Phox) ligand was identified as a non-expensive ligand that catalyzed the conjunctive cyclization reaction with high enantioselectivity. A Series of synthetically challenging enantimerically enriched spirocyclic and aryl bicyclic tertiary alkylboronates were efficiently generated using this method, and several cyclopentyl boronic esters with two continuous stereogenic centers were synthesized with high diastereoselectivity. In the third project, a Rh-catalyzed diboration reaction was successfully employed to diborate monosubstituted cyclobutenes with excellent enantioselectivity. The less sterically hindered secondary boronic ester units in the diboron products can be regioselectively functionalized using the newly developed tert-butyllithium activation-transmetallation strategy. As a result, a variety of stereochemically defined β-substituted cyclobutyl tertiary boronic esters were synthesized with high efficiency.Thesis (PhD) — Boston College, 2024.Submitted to: Boston College. Graduate School of Arts and Sciences.Discipline: Chemistry
"May This Mass Have Us Dream": Liturgical In(ter)culturation and the NuestrAmerican Reception of Sacrosanctum Concilium
No full textThesis advisor: Carlos Mendoza-ÁlvarezA lo largo de NuestrAmérica, comunidades eclesiales —algunas dentro y otras al margen de la iglesia católica romana— están creando nuevos rituales para sus celebraciones litúrgicas, ejerciendo una creatividad que se basa en y sobrepasa la interpretación normativa de la teología litúrgica que se ha desarrollado a raíz del Concilio Vaticano II. El presente trabajo explora, por un lado, cómo la recepción de tal teología conciliar por parte del magisterio episcopal latinoamericano y caribeño no ha madurado lo suficiente para atender las necesidades celebrativas de estas comunidades eclesiales y, por otro lado, cómo las comunidades mismas han retomado su propio protagonismo y creatividad litúrgica para celebrar de una manera que motive y alimente su praxis cristiana. A través de un proceso de investigación cualitativa sobre las celebraciones extra-ordinarias de las Comunidades Eclesiales de Base (CEBs) de El Salvador, como ejemplo y referente para la región, concluimos que la teología litúrgica expresada puede considerarse como fiel al Concilio y como desafío para la teología litúrgica normativa. En la primera parte de la tesis, abordamos la reflexión teológica y la enseñanza magisterial episcopal. El primer capítulo compara diferentes líneas teológicas que han influido en la recepción de la teología litúrgica del Concilio Vaticano II en NuestrAmérica, identificando un conjunto de reflexiones de(s)coloniales pendientes de incorporarse más plenamente a la tradición. El segundo capítulo traza la recepción de la teología litúrgica conciliar a lo largo de las cuatro Conferencias Generales posconciliares del Consejo Episcopal Latinoamericano y Caribeño (CELAM), concluyendo que la teología litúrgica resultante carecía de la profundidad y la madurez necesarias para que la liturgia cristiana fuera «cumbre y fuente» de la vida cristiana para muchas comunidades del subcontinente. El tercer capítulo analiza de cerca la recepción magisterial episcopal del Concilio en El Salvador, mostrando cómo una «eclesiología dual» propia del periodo posconciliar inmediato ha dado paso hoy en día a diferencias más extensas entre las CEBs y la institución eclesiástica. Tales diferencias han dado lugar a que las CEBs retomen su protagonismo y creatividad litúrgica para buscar celebrar su fe de manera coherente con su vida y praxis cristiana.
En la segunda parte de la tesis, trabajamos las experiencias vitales y litúrgicas de las CEBs de El Salvador. El cuarto capítulo justifica el uso de métodos cualitativos de investigación para la teología, reconociéndolos como herramienta importante para las actuales teologías de la liberación y de las culturas. Identificamos aquí el papel y la actividad de un «sujeto teológico descolonial», como una «telaraña» de subjetividades que resiste y re-existe a pesar de la persistente colonialidad de la religión sacrificial. Es a un nudo de esta telaraña que giramos en el capítulo 5 para concentrar la mirada y el análisis en la práctica litúrgica de las CEBs de El Salvador con la teología que las anima, reconociendo específicamente en sus altares y en los momentos eucarísticos de sus celebraciones el espíritu de la teología litúrgica conciliar. Al final, las celebraciones litúrgicas y reflexiones teológicas de las CEBs representan una expresión de la tradición viva de la fe que sigue abriendo nuevos desafíos para la vida cristiana.Thesis (PhD) — Boston College, 2024.Submitted to: Boston College. Graduate School of Arts and Sciences.Discipline: Theology
Counting differentials with fixed residues:
Full text linkThesis advisor: Dawei ChenWe investigate the count of meromorphic differentials on the Riemann sphere pos-sessing a single zero, multiple poles with prescribed orders, and fixed residues at each pole. Gendron and Tahar previously examined this problem with respect to general residues using flat geometry, while Sugiyama approached it from the perspective of fixed-point multipliers of polynomial maps in the case of simple poles. In our study, we employ intersection theory on compactified moduli spaces of differentials, enabling us to handle arbitrary residues and pole orders, which provides a complete solution to
this problem. We also determine interesting combinatorial properties of the solution formula. This thesis is organized as follows: In Chapter 1 we give an introduction to the problem and summarize the main results obtained. In Chapter 2 we review the compactification of moduli spaces of differentials and introduce various divisor classes. In Section 2.3 we explain how to identify the universal line bundle class with the divisor class of the locus of differentials satisfying a general given residue tuple and prove Theorem 1.0.1 (i). In Section 2.4 we impose exactly one independent partial sum vanishing condition to the residues and prove Theorem 1.0.1 (ii). In Section 2.5 we give a polynomial expression in terms of the zero order for the degree of mixed products between powers of the dual tautological class and the psi-class of the zero. Finally in Chapter 3 we prove Theorem 1.0.2 for arbitrary residues and investigate combinatorial properties of the solution formula. We have also verified our formula numerically for a number of cases by using the software package [CMZ2].Thesis (PhD) — Boston College, 2024.Submitted to: Boston College. Graduate School of Arts and Sciences.Discipline: Mathematics
Three Essays in the Economics of Education:
Full text linkThesis advisor: Christopher BaumThis dissertation consists of three chapters studying topics in the economics of education. Chapter 1 investigates how changes in pension policies affect households' investments in their children's education. In China, elderly individuals receive financial support from their children, in addition to pension benefits and personal savings. The researchers used a difference-in-differences (DID) analysis to compare the investment behavior of households with enterprise employees (who were affected by the 1997 pension reform) and public sector employees (who were not affected) on household investments in human capital and savings. The results showed that households expecting lower pension benefits increased their investments in education by around 2%. Additionally, a 10% decrease in the pension replacement rate corresponded to a 1.1% rise in households' investments in human capital. The study also looked at the 2015 pension reform, which aimed to reduce pensions for public sector employees, but the increase in education investment among these employees was not statistically significant, possibly due to the gradual 10-year transition period. The findings suggest that when pension income is expected to decrease, households invest more in their children's human capital development to compensate. Chapter 2 studies how being admitted via affirmative action affects minority students in universities. This paper provides evidence on the effects of college admission preferential policy on students' self-perceptions, academic performance, and career intentions. We use regression discontinuity approach to compare students just below and above the cutoff with the same type of bonus points - ethnicity-based bonus points. Because of the bonus, students just below the cutoff may study in the same university as students above the cutoff. Therefore, we are able to eliminate the “peer effect”. Actual beneficiaries report negative self-perception compared with their peers, have lower college English test scores, and are less likely to get academic awards. As for their life plans, ethnicity-based beneficiaries are more inclined to find stable jobs and hope to get married sooner. Additionally, the placebo group in which students receive bonus points for academic achievements like math or physics Olympiad shows no impostor effects. These findings demonstrate that different categories of preferential policy have different effects on beneficiaries and provide insight into studying the impact of affirmative action in psychological aspect. Chapter 3 utilizes data from the China Family Panel Studies (CFPS) to investigate the effect of having a brother on women's educational attainment. The results indicate that gender discrimination persists in Chinese households' investment in human capital, with a significant negative impact of having a brother on women's education. The one-child policy, which limits family size and creates families without male offspring, has increased women's access to education by reducing competition with preferred siblings and decreasing opportunities for gender discrimination. The increase in women's average level of access to education since 1980s is the result of the combined effects of the reduction in the dilution of family resources and the reduction in opportunities for gender discrimination.Thesis (PhD) — Boston College, 2024.Submitted to: Boston College. Graduate School of Arts and Sciences.Discipline: Economics