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Oral history of S.P.
No full text“S.P.,” a member of the class of 2023, talks with Kristen Diehl about growing up in Spanish Town, Jamaica, and her decision to attend college in the United States. She shares her early interest in medicine, her experience majoring in molecular and cellular biology, and how her career interests have expanded while attending Hopkins. She also discusses her involvement in student organizations, such as International Students at Hopkins, the Black Student Union, and Hopkins Sports Taekwondo. In addition to student groups, she describes numerous jobs and internships she's had while at Hopkins. S.P. also shares her experience adjusting from her community in Jamaica, a predominantly Black country, to living in the United States as a minority and the reality of racism on campus
An Emerging Approach to Health Equity Practice: Exploring the Implementation of Organizational Health Equity Capacity Assessments
Get PDFObjective: Public health organizations play a key role in achieving health equity, but there are significant gaps in the literature related to the assessment of organizations’ health equity capacity. The purpose of this dissertation research was to strengthen the evidence base related to organizational health equity capacity assessments (OCAs). This research benefits health departments by providing strengthened evidence related to OCA selection and implementation, helping departments to better assess their organizational capacity to design, implement, fund, manage, evaluate, and sustain health equity-oriented work.
Methods: This dissertation contains three manuscripts. The first manuscript is a scoping review characterizing the OCAs in the gray and peer-reviewed literature, providing a baseline for researchers and practitioners to find and utilize the OCA that best meets their needs. The second manuscript explores the factors that facilitate or inhibit OCA implementation, and documents the initial organizational impacts of these assessments, through two case studies conducted with the Kitsap Public Health District (KPHD) and the Rhode Island Department of Health (RIDOH). The third manuscript is a white paper exploring the programmatic opportunities for OCA implementation and recommends further research.
Results: The scoping review identified and characterized 17 OCAs that met the inclusion criteria at the time of research. All identified OCAs assess organizational health equity readiness and/or capacity, but differ regarding thematic focus, structure, and intended audience. Implementation evidence is limited. The case study expanded this evidence base, providing implementation evidence drawn from the two health department OCAs that will be useful to other departments interested in assessing their capacity. Considerations for future OCA implementation are highlighted in the results. The white paper highlighted additional research needs to strengthen OCA impact and identified potential programmatic uses of OCAs including to strengthen equitable public health emergency preparedness, develop equity-oriented public health capabilities through accreditation, and facilitate multi-sectoral, collaborative progress towards improved health equity action.
Conclusion: This dissertation advances the evidence base related to organizational health equity capacity assessments and identifies opportunities for OCA utilization and further research. Organizational health equity capacity is a unique type of capacity and should be an ongoing focal area for all health departments
Glycosylation, Trafficking, and Structural Studies in the Sporozoite Stage of the Malaria Parasite
No full textMalaria remains a major public health problem around the world, with an estimated death toll of 619 000 in 2021. Malaria is caused by the Apicomplexa parasite Plasmodium, which is transmitted by female Anopheles mosquitoes. This parasite has a complex life cycle which includes both animal and mosquito hosts. Sporozoites are the infectious stage of the parasite, being inoculated into the skin as the mosquito probes for a blood meal. In the skin, sporozoites move to find a blood vessel to enter the circulatory system to be carried to the liver, where they will develop into the next stage. Circumsporozoite protein (CSP) is a major surface protein of sporozoite. It is composed of three domains: an N-terminal domain, a central repeat region, a thrombospondin repeats type-1 (TSR) domain with a Glycosylphosphatidylinositol (GPI) anchor sequence. The TSR domain was recently found to be O-fucosylated by the enzyme Protein O-Fucosyltransferase 2 (POFUT2). CSP has been shown to be involved in sporozoite development in the oocyst, and in invasion of salivary glands and hepatocytes. Here we investigate how CSP is trafficked to the sporozoite surface, the role of O-fucosylation of its TSR domain, and the structure of sporozoite apical complex which is necessary for its invasion and motile capacity.
We found that O-fucosylation was not essential for infection of both mosquito and mammalian host, and for CSP synthesis. We also found evidence that CSP trafficking is insensitive to the Golgi inhibitor brefeldin-A (BFA), suggesting the CSP trafficking is a Golgi independent process. There are many limitations of studying the structure of the sporozoite which has left one of the most important structural features under studied. In this study, we investigated the structural details of the Plasmodium falciparum apical complex. We found a complex assortment of rings that were interconnected to each other
Oral history of L.A.
No full text"L.A." is a member of the Johns Hopkins University graduating class of 2023. In this interview with Allison Seyler, she shares the impact the COVID-19 pandemic had on her undergraduate experience. She describes where she was born, her childhood, her parents' immigration from Morocco and their careers in the United States. L.A. speaks about her Muslim identity, the geographic makeup of the town she moved to in Virginia, and the disinvestment she saw in education, particularly for people of color. In the interview, she speaks about becoming a community organizer, adjustments she made living life in Baltimore, and she elaborates on what it's like to be a FLI-first-generation college student at Hopkins. She highlights programs, professors, and courses that had profound impacts on her experience, specifically noting the importance of embracing Baltimore as your community while a student at JHU. L.A. describes her study abroad adventures and highlights a moment her mom was able to visit her in Italy. She shares insights on funding issues FLI-first-gen students face, as well as the realities of students in the same programs with very different socio-economic backgrounds. Lastly, she details what's in store for her future after Hopkins
Searching Alien Skies: On the Characterization of Exoplanet Atmospheres Using Transmission and Emission Spectroscopy
No full textSince the first exoplanet discoveries in the early 1990s, over 5,000 exoplanets have been confirmed. The variety of exoplanets and the population trends that are emerging indicate how much we have to learn about how planetary systems form and the processes that shape their evolution. Of particular interest are exoplanet atmospheres, as these will serve as our windows into the nature of exoplanets for the foreseeable future. In this thesis, we evaluate empirical trends in exoplanet atmospheres as well as techniques to facilitate the investigation of these worlds, with the overarching goal of informing observational science and technology development.
The first chapter addresses the previously-identified relationship between temperature, gravity, and atmospheric cloudiness for hot Jupiters. We perform a spectral analysis of the atmosphere of the hot Jupiter WASP-79b, which offered a prime target by which to refine the temperature/gravity/cloudiness relationship. We construct a transmission spectrum for this hot Jupiter from 0.6 - 1.7 μm and constrain the water abundance to be –2.20 ď log(H2O) ď –1.55. This chapter presents these results along with the results of an atmospheric retrieval analysis. We find the water abundance index to be lower than expected given WASP-79b’s temperature and gravity, implying a need to re-evaluate the relationship between temperature, gravity, and cloudiness for hot Jupiters.
The second chapter investigates the utility of adapting the reflectance color photometric analysis technique for transmission spectra for use in the efficient, coarse categorization of exoplanets as well as for assessing the nature and habitability of these worlds. Given the “Radius Valley” that has been observed in the super-Earth/sub-Neptune transition region, we focus on resolving the bulk composition degeneracy to aid in differentiating between these categories of exoplanets. We find that we are able to accurately constrain the atmospheric mean molecular weight in order to distinguish between super-Earth and sub-Neptune atmospheres with >90% overall accuracy using just a few specific low-resolution filter combinations, assuming noise-free spectra. We also find that increasing the number of filters does not substantially impact this performance. This method could allow for broad characterization of a large number
of planets much more efficiently than current methods permit, enabling population and system-level studies.
The final chapter of this thesis addresses the instrument and telescope specifications needed to study Earth-like planets orbiting M dwarf stars by assessing the detectability of habitability indicators and biosignatures for different aperture sizes, spectral resolutions, and numbers of observations, with a focus on emission spectra. We model atmospheric emission spectra for a TRAPPIST-1e-like planet orbiting a red dwarf star and modify these simulated spectra for different signal-to-noise ratios and resolutions. We then use atmospheric retrievals to analyze these modified spectra and assess the minimum observation parameters to determine habitability and detectability of biosignatures. We find that surface temperature is one of the few parameters that can be constrained with a 2m aperture. CO2 and O3 can be constrained for large apertures, whereas we are able to estimate lower and upper bounds on H2O and CH4, respectively. We find the 5-10 μm range to be consequential to constraining H2O and CH4, even for large telescopes, and that minimizing detector noise is critical to enabling useful observations of terrestrial exoplanets for telescopes smaller than ~2m
Extreme Heat Adaptation in Local Government: A Comparative Case Study of New York City and New Orleans
No full textAs the risk of extreme heat in urban centers is virtually certain to become more frequent and intense in the coming decades, comparing New York City, New York’s and New Orleans, Louisiana’s policy responses to those increasing dangers highlights the standard approach to protecting vulnerable populations, where alterations can be made to best suit local needs, and the numerous areas where solutions may still be implemented. Two cities at the forefront of the climate crisis in the United States, their policy solutions are guided by their history and existing adaptations and behaviors as well as the harsh realities their new climates changes have already wrought. New York City has prioritized cooling centers as a safety measure as the city is regularly seeing hundreds of vulnerable residents die, often in unairconditioned homes; New Orleans has prioritized the installation of back-up energy generation following mass blackouts caused by Hurricane Idea in 2021 and deaths of at least 10 residents in the resulting excessive heat exposure. Comparing both city’s codes, regulations, and policies, reviewing their emergency management communication strategies on social media platforms, and performing GIS analysis on cooling center locations against vulnerability criteria paints a clear picture of where heat policy stands in both cities and where it could potentially expand
Probing Kitaev Behavior in the Cobaltate Honeycomb Lattice
No full textA quantum spin liquid (QSL) is an elusive quantum state that is built upon the superposition of competing, degenerate ground states. A QSL can be produced by geometrically frustrated structures which inhibits long-range magnetic ordering down to T = 0 K and produces a finite number of equally stable ground states. A Kitaev QSL is built upon frustration of magnetic exchange interactions on a honeycomb lattice. A candidate material will have dominating Kitaev interactions, bond-dependent anisotropic exchange processes that prohibit magnetic ordering.
Initial theory promoted the investigation in S = 1/2 low-spin d5 materials with strong spin-orbit coupling, such as Ir4+ and Ru3+. High-spin d7 cobaltate honeycombs were theorized of hosting a QSL ground state with a pseudospin-1/2 stabilized by spin-orbit coupling. The added exchange processes were suggested to yield a Kitaev QSL state. With candidates such as Na3Co2SbO6 and Na2Co2TeO6 for their ideal bonding geometry, related compounds were designed and studied to test the claim of dominating Kitaev interactions.
Chapter 1 introduces important aspects of magnetism critical to understanding the intricacies of a QSL. Experimental measurements to probe structure and magnetic properties are discussed. Chapters 2 and 3 focus on the chemical manipulation of proposed candidates to further understand the underlying physics of cobaltate honeycombs. Both materials were produced via high-temperature solid-state reaction as thermodynamically stable quenching then kinetically trapped at room temperature. After structural characterization, the physical properties were measured and analyzed. Li3Co2SbO6 was developed in an approach of manipulating bonding geometry to study the impact on magnetic properties. This revealed a ferromagnetic ground state that is proximate to the QSL state. NaKCo2TeO6 is derived from an approach of manipulating interlayer distances to probe its’ effect on its magnetic properties. The comparison between its dehydrated and hydrated form displays a decrease in competing interactions, resulting in an antiferromagnetic ground state. Chapter 4 involves reports progress in modifying and improving a mechanical manipulation approach of measuring magnetization of such materials under pressure. Both paths provide insight in probing cobaltate honeycombs
THE ROLE OF PUBLIC HEALTH POLICY IN SUPPORTING STATE AND LOCAL CONTACT TRACING PROGRAMS IN THE UNITED STATES
No full textCase investigation and contact tracing (CI/CT) are fundamental public health strategies that have been used to break chains of infectious disease transmission in a variety of historic outbreaks. It is critical that public health agencies have CI/CT program components in place prior to the detection of an outbreak to ensure that these programs are ready to be leveraged when an outbreak is first detected. The goal of this research is to identify the capacities and capabilities required to implement and sustain effective CI/CT programs in United States (U.S.) state, tribal, local, and territorial public health agencies (herein, public health agencies) and to identify key federal policies and resources needed to support these programs so they can be readily leveraged in future outbreaks.
This research was conducted in three parts. First, a narrative literature review was conducted to identify the capacities, capabilities, outcomes, and impacts of CI/CT programs. Second, semi-structured qualitative interviews were held with ten state and local public health agencies as well as four experts in CI/CT to discuss the capacities and capabilities identified during the literature review and lessons learned around scaling-up and sustaining CI/CT programs during the COVID-19 pandemic and the 2022 mpox outbreak. Finally, a narrative literature review and interviews with six public health policy experts explored federal policies that impacted the scale-up and maintenance of several CI/CT capacities during the COVID-19 pandemic and the 2022 mpox outbreak.
Findings from the narrative literature review and interviews resulted in the first comprehensive documentation of CI/CT capacities, capabilities, outcomes, and impacts of CI/CT programs and a conceptual framework that illustrates the relationships between these components. The interviews explored the CI/CT capacities that should be maintained as baseline functions in public health agencies on a continuous basis to ensure preparedness to conduct CI/CT in future outbreaks, and identified lessons learned around scaling-up CI/CT during the COVID-19 pandemic and the 2022 mpox outbreak. The second narrative literature review and interviews with public health policy experts resulted in federal policy recommendations to ensure public health agency preparedness to conduct CI/CT during future outbreaks and pandemics
ADDRESSING STRESS AND THE RETENTION OF TEACHERS IN TRANSFORMATION SCHOOLS USING MINDFULNESS STRESS REDUCTION AS AN INTERVENTION
No full textTeacher turnover has been a long-standing problem in education. Turnover includes both teacher attrition and teacher migration. According to National Council for Education Statistics, the national average for teacher turnover in K-12 education for 2008-9 was 15.6%. Low-performing schools (transformation schools) experience an even higher rate of turnover. According to the Massachusetts Department of Elementary and Secondary Education (DESE) data from 2019, transformation schools can experience teacher migrations and attritions double the national average. Teacher turnover concerns school communities as it disrupts school staffing, increases school and district staffing expenditures, and impacts student outcomes and success. Empirical research, national data, and needs assessment data revealed several factors that play a role in teacher turnover ideations, including school climate, teacher-administration relationship, role requirements, professional learning opportunities, and stress. Stress became a focused construct (from needs assessment data) for this research. Made clear from data collection was a more extensive social justice issue of the cause of teacher stress dealt with systemic issues in the education system. A multi-methods study examined how the identified factors impacted five teachers in transformation high schools. Five additional teachers participated in an intervention study using and reviewing a stress reduction website designed for teachers. The intervention used a Mindfulness-Based Stress Reduction pilot program to mitigate teacher stress to decrease teacher turnover ideations. The DASS-21 (Depression, Anxiety, and Stress Score) pre- and post-intervention data indicated that the average teacher stress score decreased by 3.2 points after participating in the pilot program. The research provides a window towards identifying programming that supports teachers dealing with workplace stress but also recognizes that an intervention at the teacher level cannot change the systemic source of stress
DEVELOPING ROBUST COMPUTER PROGRAM AND ADVANCED ALGORITHMS FOR ENHANCED SOLUBILITY AND STABILITY PREDICTION IN PHARMACEUTICAL MEDIA
No full textThe evolution of the biopharmaceutical industry has predominantly concentrated on process intensification through experimental development. However, a notable gap exists in the advancement of pharmaceutical media development via computational modeling. Conventional methods of media development rely heavily on trial and error procedures, with the evaluation process for the inclusion or exclusion of components typically exceeding seven months. This thesis proposes a comprehensive approach that leverages thermodynamic and kinetic principles integrated with machine learning algorithms to improve the efficiency and accuracy of pharmaceutical media development. With this approach, a software program is developed, far surpassing traditional methods in speed and efficiency. While the primary focus of the study is on systems modeling, it also encompasses fundamental experimental techniques employed in data generation for in vitro biological systems modeling, emphasizing the critical role of a robust database. Thermodynamically, integrating short-range UNIFAC interactions with long-range ionic interactions enables the prediction of the solubility of complex pharmaceutical media, including potential precipitation phenomena. Kinetic analysis helps understand the rate of chemical reactions in the media, thereby facilitating the prediction of media stability and informing guidelines for media storage. The successful implementation of a robust computational program can direct the quantity and selection of components to be added to the media, significantly reducing manual labor and time invested, thus providing immense benefits to the pharmaceutical industry. Moreover, the study introduces a novel aspect of media development: an algorithm that dictates the order of amino acid addition, preventing precipitation issues encountered when components are simultaneously introduced. In summary, the integration of sophisticated algorithms and a graphical user interface, specifically designed to enhance the prediction of solubility and stability in pharmaceutical media, holds significant potential to streamline and optimize upstream pharmaceutical process development