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“IF YOU FALL DOWN, GET YOURSELF UP AND KEEP ON GOING”: CENTERING THE PERSPECTIVES OF PEOPLE WHO INJECT DRUGS TO EXPLORE MULTILEVEL RESILIENCE MECHANISMS AND UNMET TREATMENT NEEDS
Full text linkPeople who inject drugs (PWID) are a priority population who face a disproportionate burden of violence and trauma. Resilience has been conceptualized as the ability to bounce back from adversity and is protective in the face of traumatic experiences; yet research on resilience among PWID is limited. This dissertation addresses several gaps in the public health evidence base, including that 1) the majority of research among PWID remains risk and deficit-focused, perpetuating stigmatizing attitudes and limiting opportunities to build upon this population’s unique strengths; 2) the constructs of resilience and coping are often referred to interchangeably, and research on both constructs among people who use drugs has not been well characterized; 3) as the United States contends with the fourth wave of the opioid crisis, improved substance use treatment options are urgently needed. This work includes a comprehensive scoping review (Aim one) on how the constructs of resilience and coping are conceptualized and operationalized within the full body of research on people who use illicit substances. It follows with two qualitative studies conducted with PWID in Baltimore, MD, which characterize multilevel resilience mechanisms operating to support PWID to move forward in the face of stressors (Aim two); and identify unmet treatment needs and opportunities to improve the substance use treatment infrastructure from the perspective of this priority population (Aim three). Findings from the scoping review highlight that research on both resilience and coping focus primarily on individual-level factors, omitting the important role of external mechanisms in supporting individuals to build resilience. Aim two identifies a diverse range of multilevel resilience mechanisms employed by PWID which operate at cognitive, emotional, behavioral, social, community, structural, and place-based levels of influence, visually portraying these in a conceptual framework. Aim three characterizes unmet treatment needs from the perspective of PWID, highlighting integrated mental healthcare, non-stigmatizing treatment, and employment support as key gaps. This dissertation calls for a strengths-based approach to future research among people who use illicit drugs and emphasizes the value of centering the voices of those with lived experience in the design of treatment programs or services targeting members of this population
Greening the Redline: Urban Greening and the Racial Politics of Care in Baltimore
No full textIn recent years, post-industrial American cities like Baltimore have embraced urban greening as a low-cost tactic for revitalizing troubled inner-city communities. The transformation of vacant lots into verdant gardens through these projects acts as a potent symbol of rebirth as well as social and environmental reconnection in contexts of entrenched racial division. However, many new community-managed green spaces in Baltimore have failed to attract long-awaited reinvestment or even endure as green amenities in these communities. Overgrown and abandoned, many now further the territorial stigma they were meant to address. Building on Black feminist theorizations of care, I link the failure of these greening projects to a broader “crisis of care” in American cities. This crisis, rooted in the systemic devaluation, invisibility, and racialization of care labor, is felt most acutely in communities devastated by decades of racialized disinvestment. Challenging narratives of lack, which locate the problem of environmental inequity in impoverished minority communities themselves, I use archival sources to demonstrate how the green environs of affluent communities and the blighted environs of disinvested communities are inextricably linked within histories of racially exclusionary neighborhood protectionism. Drawing on extensive ethnographic fieldwork alongside green space stewards on both sides of West Baltimore’s color line, I trace these legacies to contemporary infrastructural inequities that act as invisible boundaries of care in Baltimore. I highlight the way greening efforts play on moralizing discourses of civic responsibility, rendering urban environmental stewardship into both a precondition for “good citizenship” and an impossible burden for many disinvested Black communities. Following the conversion of four vacant lots into community-managed green spaces, I demonstrate how the long-term viability of greening projects is regularly undermined by short-term funding horizons aimed at engineering quick fixes. Ultimately, I position care and maintenance as an under-recognized concern for environmental equity in American cities and suggest that without a focus on equitable and enduring provision of care in contexts of disinvestment, greening efforts will fail to live up to their potential as tools of repair and healing in racially divided cities like Baltimore
Directed Fluorination and the Functionalization of Selectfluor Radical Dication
Full text linkFluorine has long been an element of peculiar interest to the scientific community at large. From the role it plays in pharmaceuticals to forever chemicals, fluorine has had a profound impact in the world at large. Yet, despite all of these uses and potential, many aspects of fluorine chemistry remain shrouded in mystery, particularly pertaining to aliphatic fluorines. Over the past few years our lab has focused on the idea of directed radical fluorination in order to achieve a mild, selective fluorination of sp3 carbons. Previously this idea was used to achieve fluorination on activated benzylic sites, and highly symmetric substrates. Further work eventually opened the door for carbonyls to direct fluorination on completely unactivated C-H bonds using hydrogen bonding to achieve a highly selective product. Herein, we report further advancements, wherein hydroxy, and pyridyl groups are shown to direct fluorination. Additionally, we report the use of an electrochemically initiated system to provide an alternate pathway to achieve these reactions. Finally, we demonstrate the various unique reactivities of primary epoxides with Selectfluor Radical Dication (SRD). All in all, this assortment of new schemes and pathways to achieve selective fluorination aims to further push the notion that radical based fluorination is a valuable tool in the realm of late-stage functionalization
Net Assessments, Imposing Costs, and Reagan's Strategy to End the Cold War: An Origin Story
No full textAs the United States entered the 1970s, successive presidents spoke of the country as a decaying empire that was in relative decline compared to its Cold War adversary. The Soviet Union had caught the United States in most measures of power and appeared postured to overtake the United States as the most powerful state. Yet, when Ronald Reagan entered office in 1981, he brought with him a renewed sense of optimism. By January 1983, Reagan had signed three policy documents that together formed a strategy designed at least to bring about radical change in the Soviet political system, if not end it entirely. Reagan’s strategy seemed like the natural evolution from Truman’s NSC-68, yet much had changed in the world. What changed from the administrations of Nixon and Carter that led Reagan to adopt an assertive strategy when his predecessors had focused on using cooperation with the Soviet Union to lock in a position of strategic parity?
This thesis attempts to add to our understanding of the origins of Reagan’s cost-imposition strategy as contained in National Security Decision Directives 32, 66, and 75. It will do so by comparing Carter's and Reagan’s net assessments of the balance of power between the United States and the Soviet Union. More importantly, this thesis will compare the resulting strategies. By analyzing these results in the context of the net assessments and strategies of the Truman through Ford administrations, we will be able to identify continuity and change over time that will help identify those key differences in the way each administration defined the contest between the two states, assessed the relative balance of power, and identified a strategy to protect and advance U.S. interests. This analysis will lead to this thesis’ contribution to existing literature, it will provide a framework for strategists to use when developing competitive strategies in the contemporary era
CONTRACEPTIVE-INDUCED SIDE EFFECTS: THE ROLE OF EXPERIENCE, MANAGEMENT, AND INFORMATION ON CONTRACEPTIVE USE DYNAMICS IN KENYA
Full text linkSide effects are one of the most common reasons for contraceptive non-use, particularly in low- and middle-income countries where many women who want to avoid or delay pregnancy do not use contraception. This study investigates women’s side effect experiences, their care-seeking behavior, the information they receive during contraceptive counseling, and how these factors are related to their contraceptive use.
Using longitudinal client-exit-interview data from Performance Monitoring for Action, this study includes 3,566 family planning clients in Kenya using hormonal contraception. Clients were interviewed after receiving family planning services and by phone 4-7 months later. I ran multinomial logistic regression models to assess the association between a broad range of side effects and contraceptive use dynamics. To identify individual, community, and health facility correlates of care-seeking for side effects, I specified a multilevel logistic regression model among those who reported side effects. Additionally, I ran a multinomial model to examine the relationship between care-seeking and contraceptive use dynamics. Finally, I fit a multinomial logistic regression to explore the relationship between information received during contraceptive counseling and contraceptive use and whether this relationship differed by side effects experience.
Side effects from hormonal contraception were common, often leading to switching or stopping contraception, particularly as the number of side effects increased. Care-seeking for these experiences from a provider was mainly driven by individual and community factors rather than facility-based factors. Women who sought care were more likely to switch methods than continue or stop. Too little information during contraceptive counseling increased the likelihood of stopping contraception compared to receiving a self-perceived adequate amount of information. Additionally, the effect of receiving just enough information varied depending on the presence of side effects.
Tailored, high-quality optimal counseling is essential to help clients manage contraceptive side effects, as well-informed clients are more likely to continue contraceptive use. However, side effects still have a significant impact on contraceptive use. Improving strategies for managing side effects and developing new contraceptive options are key to enhancing user experiences and maintaining protection against unintended pregnancies
Measuring structural racism and its association with community firearm violence in New York City
No full textCommunity firearm violence is a public health crisis, especially due to unjust racial and place-based inequities in who is most impacted. Black communities bear the brunt of community firearm violence. Many cities also face endemic violence. This dissertation leveraged a police dataset on shootings to monitor the problem of community firearm violence—both fatal and nonfatal—in New York City (NYC) by giving an account of the epidemiologic patterns by sociodemographic factors. Importantly, it explored spatial patterns and select social determinants of health in the census tracts where shootings occurred. This dissertation then used latent profile analysis to model multidimensional structural racism as a latent construct for NYC census tracts and associated the resultant profiles of structural racism with Black and non-Hispanic White fatal and nonfatal community firearm violence.
Aim 1 found, on average, from 2006 to 2022, there were 1,607 shooting victims in NYC. Shootings doubled from 2019 to 2020, remained high in 2021, and trended downward in 2022. The average case fatality rate from 2006 to 2022 was nearly 20 percent, highlighting the importance of capturing nonfatal injuries. Census tracts with a high percentage of low educational attainment, unemployment, and poverty, also had a high prevalence of shootings. Next, this dissertation identified a model with acceptable fit that represented five profiles of multidimensional structural racism (Aim 2). Three of the five profiles were disadvantaged due to structural racism while the remaining two were more advantaged. The five profiles were associated with fatal and nonfatal community firearm violence such that census tracts in the profiles with higher disadvantage also had higher prevalence of violence (Aim 3).
The findings demonstrate that structural racism is an important root cause of violence. The solutions to undo the impacts of structural racism and barriers to health equity must be as multidimensional as structural racism is itself. Violence prevention efforts must be multipronged and require collaboration with marginalized communities and across many sectors. The application of the census tract-level multidimensional structural racism measure goes beyond contextualizing the outcome of violence—it can be tested with other outcomes as well as over time
CONTESTED KNOWLEDGE: “SCIENCE TALK” AND THE PURSUIT OF POLITICAL LEGITIMACY IN COLONIAL FREETOWN
Full text linkThe dissertation examines “science talk” in independent, African-owned newspapers in colonial Freetown, Sierra Leone as a lens for exploring the intersection between scientific discourse and assertions of political legitimacy in the late nineteenth and early twentieth centuries. It investigates how West Africans, through commentary and opinion pieces in these newspapers, reimagined a range of contemporary scientific topics—including eugenics, racial psychology, and occult science— to criticize colonial policies, combat colonialist tropes of African irrationality, and assert their own political authority through “rational” intellectual discourse. Science talk acted as a shield with which African intellectuals pushed for greater political self-rule, while cautiously navigating potential charges of sedition—charges that, although rarely successful, cultivated a climate of caution. Through newspapers, West Africans promoted the construction of rational publics that could appeal to the ideal of British liberalism through science talk. In doing so, West African contributors envisioned new political futures and addressed the challenges of political and professional marginalization.
Additionally, I demonstrate how newspapers operated as dynamic spaces that facilitated dialogue between political discussions and commercial interests, and how these interests blended. Newspaper writing fostered a vibrant interplay between nationalist rhetoric—often focused on concerns about racial degeneration—and the burgeoning pharmaceutical market that sought to address pressing health issues, such as infant mortality and male impotence, which contributors, using science talk, linked to being colonized. By using "science talk" as a lens, my methodology situates newspaper content within broader debates about scientific and political knowledge, thereby challenging traditional divides between different kinds of content within print media (e.g., political editorials vs. commercial advertising). Newspapers not only served as platforms for discourse but also as sites of cultural negotiation where political, commercial, and social interests converged, influencing the trajectory of political thought. This framework allows for a historically grounded understanding of the transient nature of science as an epistemological construct and discourse in colonial West Africa
SOCIAL ISOLATION AND SOCIAL STRATEGIES AMONG DISADVANTAGED YOUTH
Full text linkWhile social isolation and exclusion have long been central topics in Sociology, the study of interpersonal isolation and social strategies has been more limited. I use three sources of qualitative data to explore the role of social isolation and social strategies in the lives of young people. All three sources provide data from youth facing considerable disadvantage, but the diversity of contexts and study populations allow a deep exploration of the role of social strategies in different environments.
Drawing from interviews with 150 youth born into Baltimore’s poorest neighborhoods, I find that social isolation is a prominent theme in the narratives of these youth, and many of the youth describe deliberate strategies regarding friendships. Having a selective social strategy, such as seeking positive associates or avoiding negative ones, appears to be beneficial in maintaining employment or school enrollment. Conversely, a more isolationist strategy does not appear to be beneficial. Having no social strategy is more common among those disengaged from both work and school.
In exploring the friendship strategies of 28 migrants from Karamoja, Uganda, I find that these youth feel considerable pressure to achieve economic success as migrants while maintaining their reputations. Many intentionally seek friends whom they consider to have good character, and many avoid those considered to have bad character. They also value and seek friends who are generous with both intangible and tangible support. Some strategically limit their friendships.
From my analysis of open-ended survey responses from 308 Ugandan sex workers, I find an emphasis on the stigma experienced by sex workers, and relatedly, the need for friends who are trustworthy and amenable to emotional intimacy. These youth also seek friends who are generous with support of various kinds. Many youth value friendships with fellow sex workers, particularly for the industry-specific advice and client referrals given by their peers. Some limit their friendships.
Drawing from all three data sources, this dissertation argues that context is of central importance in the development of friendships in disadvantaged environments and that youth deploy social strategy in response to the pressures specific to the context in which they operate
Connecting Topology Optimization to Applied Workflows
No full textTopology optimization is a computational design method that has been embraced by the academic engineering research community. Yet despite its acceptance by the academic community, it sees comparatively little use by industry engineers for real-world design projects. This work seeks to facilitate the use of topology optimization for solving for real-world applications.
The second chapter of this work discusses methods of developing utilities for building irregular topology optimization domains, generating databases of micro-lattice architected materials, and methods for modelling architected materials based on triply periodic minimal surfaces. Methods of accelerating physics-based analysis of architected materials are briefly discussed.
The third chapter of this work discusses topology optimization with surrogate material models. Existing methods are discussed at length and shortcomings are identified. A new surrogate modeling method is presented, and numerical examples are used to demonstrate the proposed methods.
The fourth and fifth chapters explore the use of computational geometry to facilitate information transfer between topology optimization and computer aided design (CAD) software, including through the use of non uniform rational basis splines (NURBS). This approach stands to remove or, at least, minimize the amount of post processing needed to use topology optimization with CAD in real-world engineering workflows. This chapter provides a theoretical background on NURBS and identifies shortcoming in existing NURBS topology optimization methods. A Heaviside projection method is proposed to address these shortcomings. A range of numerical examples demonstrate the feasibility and benefits of the proposed method. Finally, the chapter ends with a prototype demonstration of how the proposed method might be incorporated in a real-world engineering workflow
Therapeutic Myeloid Cell Targets in the Immune Microenvironment of Bone and Soft Tissue Sarcomas
No full textCancer immunotherapy has become a pillar of treatment, but remains ineffective for many malignancies. Pediatric sarcomas have overall responded poorly to T cell-targeted immunotherapy, due to multifactorial challenges including a heavily immunosuppressed tumor microenvironment. Despite the failure of immunotherapy to-date, these approaches overall are an attractive alternative to cytotoxic chemotherapy, as their long-term side effects tend to be fewer and less severe compared to the risks to growth, development, fertility, and long-term cancer risk of traditional chemotherapeutic agents. Outcomes for pediatric sarcoma patients have plateaued in the last decades and new therapy approaches are desperately needed for these children.
This body of work addresses the potential of therapeutically targeting immunosuppressive innate immune cells in the microenvironment of pediatric sarcomas in combination with cytotoxic chemotherapy to improve treatment outcomes for patients affected by these cancers. We first assess the effects of delivering ADU-S100, a stimulator of interferon genes (STING) pathway agonist, on remodeling the immune microenvironment of osteosarcoma in syngeneic mouse models via analysis of gene expression, chemokine/cytokine production, and immune cell proportions in the tumor microenvironment. We demonstrate that ADU-S100 remodels the immunosuppressive macrophages in the tumor microenvironment to allow longer-term improved infiltration with cytotoxic T lymphocytes. When combined with carboplatin chemotherapy, ADU-S100 is able to induce complete tumor regression and long-term relapse-free survival in survival studies of syngeneic murine osteosarcoma models. This response is lymphocyte-dependent and dependent on STING pathway activation in the immune microenvironment.
We also identify novel innate immune targets in the microenvironment of rhabdomyosarcoma, another canonically immunosuppressed tumor. We use spatial transcriptome sequencing to assess gene expression in fusion-positive and fusion-negative murine rhabdomyosarcoma tumors. By examining gene expression in the tumor and at the tumor border with normal tissue, we identify three innate immune genes – Mif, Ccl8, and Cxcl14 – that are differentially expressed in these regions and are potential therapeutic targets to alter the immunosuppressed microenvironment of these tumors.
This work demonstrates the therapeutic power of targeting immunosuppressive myeloid cells in the microenvironment of pediatric sarcomas and proposes novel targets to manipulate these cells. Our results suggest that combination immunotherapy approaches are essential to the success of immunotherapy in some immune-excluded solid tumors and provides a foundation to design novel combination therapy approaches for pediatric sarcomas