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Clinician-Client Alignment and Collaboration in Youth Psychotherapy
No full textDespite considerable progress in youth mental health research, experts have continued to call for efforts to enhance the effectiveness and acceptability of youth psychotherapy. These efforts may be enhanced by examinations of methods, such as shared decision-making (SDM), that are designed to increase clinician-client alignment and collaboration in youth psychotherapy. Transdiagnostic youth psychotherapies, such as the Modular Approach to Therapy for Children with Anxiety, Depression, Trauma, or Conduct Problems (MATCH), may be particularly strong candidates for these methods, as they involve complex decision-making processes that can influence treatment plans and outcomes. To this end, this dissertation includes a collection of studies that are positioned to advance our understanding of the role of clinician-client alignment and collaboration in youth psychotherapy, with a focus on MATCH. In the first study, I explored SDM as a tool for navigating caregiver-youth-clinician discrepancies in the selection of youth psychotherapy targets, which can serve as a barrier to clinical decision-making, as well as building inclusive transdiagnostic treatment plans that integrate the unique perspectives of clinicians, caregivers, and youths. In the second study, I extended this focus on clinician-client alignment in the selection of youth psychotherapy targets to clinician-client alignment in the selection of an initial MATCH treatment protocol. Specifically, I examined measure-based clinician-client alignment—that is, the extent to which a clinician selected a treatment option that aligned with the “best-fit” for a given youth client, based on the information shared by the youth and their caregiver in surveys—as a predictor of caregiver-reported and youth-reported severity ratings of youth symptoms and psychotherapy top problems across treatment. Overall, improvements in these outcomes were found to be greater when the clinician-selected MATCH protocol aligned with the best-fit protocol of at least one of the clients (i.e., caregiver client and/or youth client), compared to when the clinician-selected MATCH protocol did not align with the best-fit protocol of either client. Finally, in the third study, I complemented this work on measure-based clinician-client alignment with that focusing on a second form of clinician-client alignment in youth psychotherapy: interaction-based. Specifically, I examined interaction-based clinician-client alignment and collaboration—that is, the extent to which a clinician includes clients in decision-making processes during sessions—within the context of MATCH. First, I conducted a comprehensive scoping review of measures designed to capture SDM elements in healthcare and used this information to develop, apply, evaluate, and extract preliminary data from an observational coding system of interaction-based clinician-client collaboration in 222 audio-recorded MATCH sessions. Trained coders were found to achieve high levels of interrater reliability, and we identified challenges in assessing the construct validity of this measure. Overall, clinicians were observed to use at least one SDM element in most sessions with both youth and caregiver clients but to a minimal level. Additionally, clinicians were found to apply SDM elements to a greater extent with caregiver, compared to youth, clients, despite more frequently using SDM elements with youth, relative to caregiver, clients. Taken together, this work is positioned to advance our understanding of how clinicians approach decision-making in youth psychotherapy, as well as how clinicians can leverage multiple forms of clinician-client alignment and collaboration to cultivate more inclusive and responsive approaches to care. This collection of studies has the potential to inform future research, such as that examining the extent to which clinician use of SDM may impact youth psychotherapy outcomes and the potential therapeutic benefits of SDM-focused training for clinicians.Psycholog
Addressing the Extremes of Reactivity in Small-Molecule-Catalyzed Stereoselective Glycosylation
No full textGlycosides play disparate yet essential roles in biology, and as such their study is of great
importance to human health. To perform such studies, the stereocontrolled laboratory synthesis of
glycosides remains a necessary endeavor. Despite this, the development of general methodology
for stereoselective glycosylation is an unmet challenge in organic reaction development. This lack
of generality can be attributed, among other reasons, to the incredible range of reactivities present
across the various glycosyl donors of biological relevance, owing in turn to their diversity of
structures. This is especially problematic for the stereoselective glycosylation of donors that sit at
the extremes of reactivity, both high and low, where methodology for glycosylation with biomass
sugars is typically not applicable. We aim to address these shortcomings through the development
of general catalytic glycosylation protocols that are applicable across donor classes.
In Chapter 1, we discuss the relationship between structure and reactivity in chemical
glycosylation, highlighting key studies that probe this relationship. We will discuss the
stereochemical implications of these structure-reactivity effects, with an emphasis on
glycosylation with highly reactive 2-deoxyglycosyl donors and highly unreactive glucuronyl
donors. We will then discuss current strategies for the stereoselective preparation of 2-
deoxyglycosides and glucuronides, as well as the limitations of these strategies. Finally, we will
summarize our research group’s development of bis-thiourea-catalyzed stereoselective
glycosylation, including key findings, mechanistic studies, and limitations that studies documented
in this dissertation aim to address.
In Chapter 2, we document the development of bis-thiourea-catalyzed methods for βselective 2-deoxy- and 2,6-dideoxyglucosylations of natural products, carbohydrates, and amino
acids. Disarming ester protecting groups were necessary to counter the high reactivity of 2-
deoxyglycosyl electrophiles toward non-stereospecific SN1 pathways. Differing catalyst structures
were found to be optimal for use of 2-deoxy- and 2,6-dideoxyglycosyl donors. Alcohol and phenol
nucleophiles with both base- and acid-sensitive functionalities were compatible with the catalytic
protocol, enabling access to a wide array of 2-deoxy-β-O-glucosides.
In Chapter 3, we document the successful application of metal–salen catalysis towards β-glucuronidation of alcohols, phenols, and anilines via stereospecific opening of 1,2-
anhydroglucuronate electrophiles. The optimized protocol is mild and pH-neutral, enabling β-glucuronidation of complex pharmaceuticals and natural products bearing acid-sensitive and
Lewis-basic functionality. Kinetic studies are consistent with a transformation that is overall first order in catalyst, which contrasts previous metal–salen-catalyzed epoxide opening reactions where
second-order rate dependence on catalyst is observed.Chemistry and Chemical Biolog
How Feedback Shapes Galaxies and the Stories We Tell About Science
No full textGalaxies evolve through a continuous exchange of mass and energy with their surroundings, a process known as the baryon cycle. ``Feedback" from stars and supermassive black holes, in the form of radiation and winds, is predicted to regulate this cycle by modulating how gas cools, forms stars, and is reheated and/or expelled. This dissertation explores how feedback operates across a range of environments and mass scales, using a combination of multi-wavelength observations and theoretical modeling.
The first two chapters examine the impact of supermassive black hole / active galactic nuclei (AGN) feedback in the Universe's most massive galaxies through multi-wavelength observational studies of the SDSS J1531+3414 () and Abell 2597 () clusters of galaxies. In SDSS J1531+3414, I identify one of the most powerful AGN outbursts known, releasing over of energy. This outburst is traced by a giant X-ray cavity and steep-spectrum fossil radio lobes, with a reservoir of of molecular gas tangentially connected to it. The gas appears to have been uplifted by the powerful outburst, and is now spatially offset from a striking 28 kpc-long chain of 19 stellar superclusters. Together, these features suggest that a recent major merger has disrupted the feedback loop in the cluster's central massive galaxy, decoupling star formation from the cold gas that fuels it.
In contrast, Abell 2597 hosts a more stable, long-lived feedback loop. Deep \textit{Chandra} X-ray observations reveal multiple generations of AGN feedback-driven cavities and potential 150 kpc-scale shocks, consistent with recurrent AGN outbursts on 10 year timescales. Although the AGN injects mechanical energy at a rate of erg s, sufficient to prevent overcooling, infrared and millimeter observations reveal that residual cooling persists at 15 \msun\ yr, maintaining a \msun\ cold gas reservoir draped around the cavities in the central galaxy. These features point to ongoing condensation from the intracluster medium, likely aided by AGN-driven uplift, and suggest that cold gas accretion—not hot-mode Bondi flow—sustains the central AGN.
To extend this analysis beyond the massive galaxies at the centers of clusters and into the lower-mass regime where stellar feedback dominates, Chapter 3 introduces the TNG SAM, a new semi-analytic model of galaxy formation. Built on the Santa Cruz SAM framework and calibrated to baryon flows measured in the IllustrisTNG-100 simulation, the TNG SAM captures key physical processes shaping galaxies in halos from to . Several major updates distinguish the model: a cooling time-based prescription for gas accretion that replaces the classic hot/cold mode dichotomy; revised treatments of halo gas re-accretion and cooling; explicit modeling of both galaxy- and halo-scale outflows; and metallicity-dependent mass loading and metal enrichment prescriptions that track the circulation of gas and metals between galaxies and their environments. These changes allow the TNG SAM to reproduce IllustrisTNG predictions for stellar mass, cold and hot gas mass fractions, and gas and stellar metallicities to within , out to . As a result, the model offers a powerful, computationally efficient tool for interpreting the baryon cycle in galaxies where direct observations of the CGM remain limited.
Finally, this dissertation turns from the physical processes shaping feedback to the infrastructures, labor systems, and politics that shape the production of astronomical knowledge. Drawing on archival and historical records, I examine the role of Black South African workers in building and maintaining early 20th-century American observatories in South Africa. These workers, whose contributions have been largely excluded from the scientific narrative, laid the physical foundations that enabled U.S. institutions to extend their scientific reach into the Southern Hemisphere. By recovering these histories, I trace how systems of racial capitalism and settler colonialism materially structured the development of modern astrophysics—not only through the land and labor they extracted, but also through the epistemologies they reinforced. Just as feedback governs the cycling of matter and energy in galaxies, it offers a lens for understanding how knowledge itself is generated, sustained, and challenged within scientific institutions.Astronom
Complete Community Control: A Historical Ethnography of Educational Self-Determination at St. Joseph’s Community School (1969-1985)
No full textWhat educational models have African American educators and families developed to combat the pervasive impacts of antiblackness in education? This study explores the practice of self-determined education through a historical ethnography of St. Joseph’s Community School, a women-led, community-controlled institution formerly located in Roxbury, a predominantly Black neighborhood in Boston, Massachusetts. Foregrounding the voices of Black women, I pair the historical methods of archival analysis and oral history collection to explore St. Joseph’s social and historical context, as well as the school’s leadership model, political philosophies, partnerships, pedagogy, and curriculum. As both an institutional history and a social history of Black women and families’ educational activism, the study departs from traditional historical narratives that frame desegregation era Boston as a site of antiblack violence – a discursive practice that overlooks the city as a site of African American agency and organizing. Instead, I draw upon Black feminist theory to argue that Black Bostonian educators, mothers, and perhaps most surprisingly, politically active nuns, engaged in educational leadership as an act of Black Power. In doing so, the school community constructed their own definitions of Black Power that diverged from dominant historical frames of patriarchal and militaristic ideology and centered the development of a rigorous, culturally relevant educational alternative for Black children. This study provides readers the opportunity to rethink the key actors, sites, and practices of the Black Power Movement and to better understand educational practices that foster Black students’ academic achievement and holistic well-being. Ultimately, this study aims to engage the past educational pursuits of Black women and families to inform a justice-based vision for the future of education.Educatio
Robust Inference in Financial Markets
No full textThis thesis studies thick tails, found across financial markets, which present challenges for modern financial theory. Notably, traditional tools in financial econometrics deteriorate in the presence of thick-tailed predictors. The standard Koenker-Basset estimator of linear quantile regression is an example of a model with an unbounded influence function and is thus vulnerable to those predictors. To address thick tails, this thesis proposes a robust estimator of the linear quantile that is computable using existing software and has a bounded influence function, making it less vulnerable to non-Gaussian conditions frequently found in financial markets. Statistical properties of this estimator and empirical results when this estimator is used on market data are also described. Bounded influence functions are useful outside of purely financial econometric applications. This thesis connects the robust properties of the estimator developed to differential privacy, a mathematical privacy tool that protects individuals from identification under data analysis, and proposes differentially private and pseudo-private estimators. This estimator works well in comparison with existing private and pseudo-private regression methods, reducing noise under the same privacy budget constraints. Specifically, this paper presents three separate differentially private algorithms, and shows their utility in simulated experiments and real world data. In addition, this paper presents a pseudo-private algorithm for use in cases with small sample size where differential privacy is not feasible. Using the motivating example of Opportunity Atlas data, the estimator decreases noise significantly.Applied Mathematic
Functional & Taxonomic Identification of Microbial Inflammation in COVID-19 & Parkinson’s Disease: A Metagenomic Analysis
No full textPast metagenomic research links disruptions in the gut microbiome to various inflammatory and neurological conditions, including Parkinson’s disease (PD). Recent studies show that PD and SARS-CoV-2 (COVID-19) infections are associated with decreased microbial diversity, altered renin-angiotensin system (RAS) signaling, and increased oxidative stress. This thesis hypothesized a shared dysbiotic signature between these conditions and sought to identify overlaps relative to neurologically healthy controls (NHC). A metagenomic analysis of publicly available datasets from Wallen et al., 2022 (PRJNA834801), and Nguyen et al., 2023 (PRJNA976404) was performed to characterize microbial taxonomy (MetaPhlAn2), functional pathways (HUMAnN2), and to identify statistical biomarkers (QIIME2, MaAsLin2). The goal was to compare PD and COVID-19 metagenomes. Contrary to the initial hypothesis, results revealed distinct, independent microbial signatures. The COVID-19 group showed significant taxonomic imbalance, with increased alpha diversity, lower levels of beneficial bacteria, and higher levels of opportunistic bacteria. In contrast, the PD group's microbiome was similar to that of the NHC group, both taxonomically and functionally. Despite notable taxonomic shifts in COVID-19, functional diversity remained stable across all groups, indicating high functional redundancy. Although no standard inflammatory profile was identified, this study provides a robust workflow for the computational analysis of metagenomic data.Extension Studie
Application of Lipid Nanoparticle (LNP) Design and Optimization Concepts to the Emerging Field of Protein-Based Virus-Like Particles (VLPs)
No full textLipid nanoparticles have emerged as the dominant delivery technology for genetic
medicines, reaching global use and attention with the success of mRNA-based COVID
vaccines. However, LNPs face notable challenges related to biodegradability,
extrahepatic targeting, and immunogenicity. VLPs, a newer class of protein-based
nanocarriers, present a compelling alternative with distinct advantages including inherent
biodegradability due to non-synthetic components, cellular targeting capability by
leveraging viral surface proteins, and reduced immunogenicity enabling repeat-dose
therapeutics.
This thesis systematically evaluates the applicability of LNP design and
optimization concepts to VLPs to help explore parallels and potential divergences to
investigate if VLPs should be considered the superior delivery technology. The concepts
explored include mechanisms of nanoparticle formulation, cargo encapsulation,
biodegradability, cellular uptake, endosomal escape, and immune system evasion. While
significant design parallels exist, the primary challenge limiting VLPs is their slower
manufacturing speed due to reliance on cellular expression systems. The conclusion of
this document proposes a future usage of VLPs as a modular technology to help increase
the speed of discovery and help bring VLPs into the mainstream.Extension Studie
The Endurance of Fiqh in an Age of Sharīʿa: Islamic Law in Late Colonial Sudan
No full textThis dissertation explores Islamic law and reform in colonial Sudan. It relocates study of the period from state judiciaries and reformist polemics, both well attested to in the literature, to the learning circles of Sudan’s Mālikī school of law (madhhab). It focuses on three scholars active in that country’s mid-twentieth century: ʿUthmān b. Ḥasanayn Barrī al-Jaʿalī (d. 1960), Muḥammad al-Amīn al-Shinqīṭī (d. 1974), and Abū Ṭāhir Ḥasan Fāy al-Bijāwī (d. 1984). Through a close reading of their work, oral accounts of their lives, and unstudied biographical notes, this dissertation examines the ways that each attempted to resuscitate a Mālikī tradition beset by colonial reforms from above and revisionist critiques from below. The following chapters contend that their doing so problematizes a number of assumptions common to the study of Islamic law and Africa. Rather than a Sudan indifferent to the legal debates more often associated with Islamic scholarship elsewhere, al-Jaʿalī, al-Shinqīṭī, and al-Bijāwī were deeply invested in contests over law and authority circulating throughout the Islamic World. Their preoccupation with law and particularly legal methodology was not unique. It built on a tradition of Mālikī teaching, scholarship, and jurisprudence (fiqh) in Sudan that stretched back some four centuries. Their scholarship also calls for revisiting Islamic law today. Al-Jaʿalī’s revision of imitation (taqlīd) and al-Shinqīṭī and al-Bijāwī’s use of proof texts (dalīl) present a vision of traditionalism and reform in which neither was exclusive of the other. Their efforts to transform Islamic law from within the madhhab rather than from outside it suggest that the postformative legal tradition was perhaps more resilient – and elastic – than is often supposed. Together they present the case of a madhhab in modernity deeply involved in its own tradition of reform.Near Eastern Languages and Civilization
Understanding Peripheral Biological Variability in Posttraumatic Stress Disorder: Omics and Causal Approaches
No full textPosttraumatic stress disorder (PTSD) is the quintessential trauma-related psychiatric disorder that profoundly impacts long-term health. A growing body of literature links PTSD to elevated risks for cardiometabolic diseases and premature mortality, with stress-activated biological processes in both central and peripheral systems discussed as potential mechanisms. Recent studies assessing associations between PTSD and biological differences in markers obtained from peripheral tissues (e.g., inflammatory markers) have highlighted promising directions for improving our understanding of PTSD pathophysiology and health consequences. However, current knowledge remains limited regarding the relevance of different types of biological data and the utility of various methodological approaches. This dissertation examines links between PTSD symptoms and three types of biological data derived from peripheral blood samples: metabolomics, DNA methylation (DNAm), and triglycerides. Applying novel approaches in our investigations, we aimed to improve the characterization of PTSD-related biological differences and explore their implications for long-term health.
In Chapter 1, we pursued the first large-scale, population-based metabolome-wide investigation of PTSD, using plasma metabolomics data from three subsamples (total N=2,835 women) nested within the Nurses’ Health Study II (NHSII). Building on prior metabolomic analyses of depression and anxiety, our results revealed shared and distinct metabolic alterations linked to PTSD versus depression or anxiety. Notably, we identified 29 metabolites (primarily elevated glycerophospholipids and glycerolipids) associated with persistent PTSD symptoms but not with remitted PTSD. Our findings highlight the considerable metabolic impact of chronic, non-remitted PTSD symptoms and provide insights into mechanisms that may underlie elevated cardiometabolic disease risk in individuals experiencing PTSD symptoms.
In Chapter 2, we offered a proof-of-principle for using DNA methylation data from peripheral blood samples to identify subtypes of trauma-exposed civilians with meaningful differences in PTSD symptoms and health. Exploratory analyses were performed in a subsample of women in NHSII (N=707), with external validation in the Detroit Neighborhood Health Study (N=324), a longitudinal cohort of predominantly non-Hispanic African American men and women. While specific subtype classifications remain preliminary, our study demonstrated that peripheral DNAm profiles may capture both short-term and long-term information about PTSD symptom severity and physical health. This work supports the utility of a multivariate approach linking biological variation to symptom and health heterogeneity.
In Chapter 3, we examined the bidirectional relationship between PTSD and circulating triglycerides, triangulating evidence from a summary data-based two-sample Mendelian randomization study and observational analyses in NHSII. Our findings supported an effect of PTSD on elevated triglyceride levels, whereas the impact of triglycerides on PTSD risk appeared limited. By carefully considering potential biases in each design and performing a series of sensitivity analyses to address these concerns, this study improved our understanding of the causal relationship between PTSD and triglycerides.
Taken together, findings from these three studies highlight the importance of understanding peripheral biological differences linked to trauma and PTSD. Both broad, hypothesis-generating strategies and focused, hypothesis-testing investigations can offer valuable insights. A key direction for future work is to assess the extent to which these biological differences may mediate long-term health risks related to PTSD.Population Health Science
Essays in Behavioral Development Economics: Social Frictions in Labor and Learning
No full textThis dissertation presents three essays in behavioral development economics that study how social and psychological frictions shape the effectiveness of development policies and programs. While large-scale investments in development have contributed to substantial reductions in global poverty, interventions can generate muted or heterogeneous impacts.
The essays examine how emotions, social norms, stigma, and interpersonal relationships influence behavioral responses to policies aimed at improving well-being, productivity, and aid allocation.
The first chapter studies the role of peer group structure in shaping the effectiveness of a school-based trauma intervention in Zimbabwe. Using a randomized controlled trial across lower-secondary schools, I evaluate a program that combines teacher training with a student-facing, peer-based intervention known as Freedom Clubs. I develop a simple model in which participation in group-based trauma programming entails social image costs that vary with relational closeness. Consistent with this framework, I find that treatment effects on trauma-related outcomes are heterogeneous: impacts are strongest when students are grouped with either very close peers or relative strangers, and weakest at moderate levels of closeness. Given the limited number of schools and clusters, statistical power is constrained and the resulting estimates should be interpreted cautiously. Noticeably, average effects are small and imprecisely estimated. Teacher training alone also yields few consistent benefits, with point estimates that, while imprecisely estimated, tend to move in negative directions.
The second chapter examines how inequality generates behavioral responses in low-income labor markets and how informal redistributive institutions may mitigate these responses. Using original survey data from rural western Kenya, I document strongly egalitarian fairness preferences, widespread expectations of envy and sanctioning following unequal gains, and the ubiquity of social and kinship taxation. Experimentally varied hypothetical scenarios show that inequality is expected to substantially increase harmful sanctioning behaviors, but that these effects are attenuated when advantaged individuals are embedded in resource-sharing relationships, particularly when inequality arises through luck rather than favoritism. The chapter also presents a pre-analysis plan for a lab-in-the-field experiment with sugarcane factory workers to test these mechanisms under real incentives.
The third chapter studies the political economy of development assistance by examining how U.S. cargo preference regulations affect the allocation of food aid. Using historical data on U.S. food aid shipments and freight rates, I show that cargo preference requirements raise transportation costs and distort aid allocations.Public Polic