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IMPROVING THE SUSTAINABILITY OF EV BATTERY SUPPLY CHAINS: PROSPECTS FOR SOURCING AND RECYCLING IN THE UNITED STATES
Get PDFAs the United States sets ambitious EV deployment priorities to reduce emissions and improve transportation sector sustainability, the supply chain on which EV batteries relies poses challenges to overall decarbonization and environmental goals. The mining and processing procedures required to produce EV batteries are energy-intensive and pose significant environmental liabilities. Likewise, established hydrometallurgical and pyrometallurgical recycling relies on thermal processes and chemical agents that often require fossil fuels or toxins that contaminate water, land, and air resources. This research paper thus evaluates the energy intensity and environmental liabilities of key mining and recycling processes for EV batteries in light of the transition from lithium nickel manganese cobalt (NMC) to lithium iron phosphate (LFP) chemistries in the United States. It ultimately aims to use this literature and technology review of existing sourcing processes (for lithium, nickel, manganese, and cobalt), existing recycling methods (hydrometallurgical, pyrometallurgical, and direct), and evolving trends at both supply chain nodes to address how and why an integrated approach to sourcing and recycling can drive overall EV battery supply chain sustainability
Generative Model Assisted Sampling of Multiscale Dynamical Systems
Get PDFFor complex dynamical systems effectively modeled by either stochastic or deterministic differential equations, sampling the phase space of the system is a crucial modeling step in many applications, from modeling protein folding to the design of a chemical reactor. These problems are often multiscale in nature and can often be described in terms of low-dimensional effective “slow'' reaction coordinates; the remaining “fast'' degrees of freedom populate an equilibrium measure on the reaction coordinate values. Over the years, enhanced sampling techniques coupled with molecular simulation have been developed. An intriguing analogy arises with the field of Machine Learning (ML), where generative models such as Score-Based Diffusion Models (SGMs) and Generative Adversarial Networks (GANs) can produce high dimensional samples from probability distributions parameterized by a relatively small number of degrees of freedom. This sample generation returns plausible high dimensional space realizations of a model state, from information about its low-dimensional representation. In this dissertation, I present an approach that couples physics-based simulations and biasing methods with ML-based conditional generative models for sampling conditional distributions of stochastic dynamical systems and initializing on low-dimensional manifolds in deterministic dynamical systems. The “coarse descriptors'' on which we condition the fine scale realizations can either be known a priori or learned through nonlinear dimensionality reduction such as diffusion maps
SEX IN THE TIME OF COVID: IMPACT OF COVID-19 ON AN HIV PRE-EXPOSURE PROPHYLAXIS INTERVENTION FOR MALE AND TRANSGENDER FEMALE SEX WORKERS WHO HAVE SEX WITH MEN IN THAILAND
Get PDFThe purpose of this study is to investigate the impacts of COVID-19 on sexual behaviors and adherence to PrEP and other condom usage among participants enrolled in the COPE study. Another goal of this dissertation is to review existing literature of PrEP delivery models focused on key-population driven and community-based organizations.
A web-based literature search was conducted to filter 513 articles down to 5 eligible studies to review. Statistical analysis was conducted comparing a period before COVID-19 restrictions were implemented in Thailand, to the same period in the height of the pandemic. Descriptive statistics were conducted utilizing two-sample t-tests and Pearson’s chi-squared tests. A negative binomial regression to see if those who had a sexual partner in the last 30 days and had met at a venue were more likely to have more partners pre versus during the COVID study period. Pearson’s Chi-Squared tests and a logistic regression were completed to look at adherence and condom usage at last occurrence of sex.
There is limited published literature analyzing PrEP delivery models within key-population driven and community-based organizations. The available published literature shows high levels of PrEP initiation and adherence among priority populations when programming is implemented in these settings. When looking at the impacts of COVID-19, individuals who identified transactional sex as their primary source of income reported a lower likelihood of having met a partner at a venue, dropping from 40.4% pre-COVID to 37.5% during COVID (p= <0.01). A decrease was observed in the average number of partners during the past 7 days for the COVID study period. There was a correlation between finding a transactional partner at a venue and decreased likelihood of having had protected sex. Many of the differences between the two time periods were found not to be statistically significant.
More research must be conducted exploring existing models of PrEP delivery and their impact within key-population driven and community-based organizations. There seems to be some impact of COVID-19 on sexual behavior of participants enrolled in COPE. Additional analysis is needed to assess the impacts of COVID-19 in a more holistic manner due to study limitations
THE CURRENT STATE OF DIGITAL HEALTH ACCESS FOR PATIENTS WITH CHRONIC DISEASES IN RURAL INDIA: A SCOPING REVIEW
Get PDFAbstract
Background
Chronic diseases are on the rise in India, especially in rural areas where access to healthcare is limited. Health information technology (health IT), such as telemedicine and mHealth, hold promise in improving healthcare access in rural settings.
Objective
To summarize the types of health IT tools and their effectiveness in improving healthcare access for patients with chronic diseases in rural India.
Methods
We followed the scoping review framework developed by Arksey and O'Malley. We conducted a search in PubMed, Scopus, Google Scholar, and the Indian Journal of Medical Research. We retrieved studies of health IT interventions in chronic disease patients conducted in rural settings in India.
Results
We found 16 articles that were relevant to our search. Most of the studies found health IT tools were feasible to use in rural settings (n=12, 75%). Telemedicine and mHealth were the most used health IT tools (n=6, 37.5% & n=10, 62.5%, accordingly). When compared to standard care and baseline data, health IT solutions, both telemedicine and mHealth, resulted in statistically significant control of chronic diseases such as hypertension and diabetes (n=4, 25% & n=5, 31.25%). Health IT also proved to be an extremely useful tool in chronic disease screening and diagnosis using telemedicine and mHealth (n=6, 37.5% & n=3, 18.75%), improving treatment adherence using mHealth (n=2, 12.0%), participant acceptability of telemedicine (n=1, 6.25%), raising awareness about chronic diseases (n=1, 6.25%), and improving health behavior and attitude (n=1, 6.25%).
Conclusion
Our findings indicate that health IT tools such as telemedicine and mHealth could be useful in improving healthcare access in rural settings in India. Health IT solutions should also be prioritized by policymakers and incorporated into the Indian health system and national initiatives
Investigation of a primate-specific receptor in histamine-independent pruritus
No full textMas-related G protein-coupled receptors (Mrgprs), a GPCR family cloned at the turn of the millennium, have emerged as important receptors mediating histamine-independent pruritus. Using unbiased high-throughput drug screens, we identified MRGPRX4, a primate-specific, sensory neuron receptor, as a potential target for phosphate-modified compounds. A humanized mouse model expressing MRGPRX4 in sensory neurons exhibited robust phosphomonoester prodrug-evoked itch. Single-particle cryogenic electron microscopy (cryo-EM) elucidated the binding mode of MRGPRX4 in complex with a phosphate-modified compound and identified critical amino acids residues responsible for the binding
DESIGN AND ANALYSIS OF A METAMATERIAL ABSORBER FOR ELECTROMAGNETIC APPLICATIONS
Get PDFThis thesis explores the design and characterization of metamaterials for enhancing electromagnetic absorbance in the context of electromagnetic compatibility (EMC). Electromagnetic radiation is a pervasive concern in various industries, with potential interference and unwanted emissions impacting the performance of electronic devices. Metamaterials offer a promising solution for controlling and manipulating electromagnetic waves through their unique electromagnetic properties.
The research focuses on the design and optimization of a metamaterial structure that is tailored for efficient electromagnetic absorbance. By tailoring the geometric and electromagnetic properties of the metamaterial, the absorption of specific frequencies or a broad range of frequencies can be achieved. The proposed metamaterial structures are analyzed using various numerical simulations and electromagnetic solver tools.
The thesis investigates various aspects of metamaterial design, including the selection of appropriate materials, geometric configurations, and fabrication techniques. The influence of key parameters on the absorbance performance is explored to optimize the design for desired EMC applications. Furthermore, the impact of incident angle, polarization, and environmental factors on the absorbance capabilities of the metamaterials is studied.
In addition to the design and characterization, the thesis also examines the potential applications of the metamaterial absorbers in real-world EMC scenarios. The effectiveness of the metamaterials in suppressing electromagnetic interference and reducing unwanted reflections is assessed. Practical considerations such as scalability, cost-effectiveness, and compatibility with existing systems are also addressed.
The results of this research contribute to the understanding and advancement of metamaterial-based electromagnetic absorbance for EMC purposes. The findings have implications for various industries where electromagnetic compatibility is crucial, including telecommunications, aerospace, automotive, and consumer electronics. By leveraging the unique properties of metamaterials, this work seeks to enhance EMC performance and pave the way for improved electromagnetic radiation management in modern technology systems
Modern Divorce under Patriarchy: Family, Law, and Gender Inequality in Chinese Courts
No full textThis dissertation examines the relationship between family and state, focusing on how the intimate sphere of family, a primary site of gender and power dynamics, is deeply influenced by state intervention. Traditionally, sociological and demographic studies of the family have centered on the framework of the public-private dichotomy, which views the family as a private realm shielded from state intrusion. This dissertation addresses this oversight by exploring how the state impacts family life, particularly through the lens of divorce—a legal process heavily influenced by state policies. China provides a unique context for this investigation due to the state's historical and ongoing involvement in the family. Using a novel database of over three million divorce cases from 2007 to 2021, the dissertation analyzes three key areas of contention in divorce proceedings: brideprice repayment, child custody, and property distribution.
The first essay highlights the role of brideprice in Chinese marriages. On the one hand, the practice of brideprice has retained its traditional meaning as an interfamily compensation for female labor and fertility. On the other hand, the old practice of brideprice has evolved into an intergenerational endowment for the newlyweds. Focusing on the two frames of brideprice, this essay asks how the meanings attributed to brideprice payments at the time of marriage shape brideprice repayments at the time of divorce.
The second essay considers how stereotypical gender roles and patrilineal traditions influence the outcome of child custody. A puzzling contradiction was observed in contested divorce cases: although fathers were the primary caregivers in only about three percent of these custody cases, they won custody in more than half of them. This essay explains this contradiction by integrating two mechanisms: the significant role of paternal grandparents who often act as representatives for fathers in childrearing, and the common scenario where fathers are the sole owners of the family home in custody disputes.
The third essay studies the implications of a radical change in property distribution rules that redefined economic justice at divorce by transforming what was previously considered joint marital property into individual property. Prior to this change, property distribution at divorce in China emphasized "equitable distribution," taking into account various forms of contributions to the marriage as part of a joint enterprise. In August 2011, a significant shift in property distribution rules placed greater emphasis on legal titles and financial contributions. While the law on the books does not discriminate between men and women, it tends to benefit property owners. However, in practice, the law disadvantages women, who often bear the burden of unpaid domestic work, rendering their non-monetary contributions increasingly trivial in the division of marital property. This essay also examines the unintended consequences of these legal changes, which extend beyond property rights to include issues related to child custody
Die Like Chamran: Iran and the Art of Proxy Warfare
No full textThis study examines how the Islamic Republic of Iran established a network of non-state Shia Islamist militant clients across the Middle East and how those proxies serve Iran’s national security interests. It assesses the extent social links, in particular clerical networks, familial connections, and personal relationships explain Iran’s success in creating and sustaining loyal non-state clients over time. And further, it seeks to explain what imprints Iranian support leaves on its clients’ organizations that make these proxy relationships durable and successful. It argues that Iran’s success in creating and sustaining loyal non-state clients is best attributed to a combination of personal connections between Iranian officials and foreign militants, shared ideological worldviews, and institutional bonds. These factors are mutually reinforcing and foster lasting ties at the network, organizational, and strategic levels between Iran and its proxies that advance Iran’s military, political, cultural, and economic influence in the region. To demonstrate the argument, this thesis considers three primary cases: Lebanese Hizballah, the Badr Organization, and Asa’ib Ahl al-Haqq and three lesser cases, the Fatemiyun Division, the Houthis in Yemen, and HAMAS. It evaluates Iran’s role in the formation and development of each of these groups and pays particular attention to the social, ideological, and organizational foundations of Iran’s relationships with its proxies. It finds that Iran’s most successful proxies are part of a transnational network of Shia Islamist clerics and militants that share the Iranian regime’s revolutionary worldview and have institutional ties to Iran’s bureaucratic capacities dedicated to proxy warfare, most notably the Islamic Revolutionary Guard Corps Qods Force
Explaining Jordan's Relative Success in U.S. Security Cooperation: The Development of the Jordanian Armed Forces-Arab Army and U.S. Security Cooperation Partnership
No full textTo understand Jordan’s relative success in U.S. security cooperation, I assessed the major factors that contributed to the political-military development of the Jordanian Armed Forces-Arab Army (JAF) and U.S. security cooperation partnership to provide a better understanding of how the U.S. might improve security cooperation partnerships to achieve “mutual security goals consistent with U.S. national security objectives” in a complex security environment (DSCA n.d.), as the Middle East continues to remain strategically vital to the U.S. My thesis answers the question: What explains the relative success of the JAF and U.S. security cooperation partnership over time? I employed process tracing methodology to determine which variables, generalizable beyond this individual case, explain the relative success of the JAF and U.S. security cooperation partnership. By analyzing the political-military development of the JAF and U.S. security cooperation partnership from the JAF’s pre-colonial foundations in 1918 to the 2022 U.S.-Jordan Memorandum of Understanding (MOU), this thesis reveals the political-military factors that contributed to and distinguished the development of the JAF in relation to U.S. security cooperation and what relative success in U.S. security cooperation partnership looked like. This thesis demonstrates that the JAF’s establishment through effective state building, which produced a competent military for the U.S. to work with, and the nature of the U.S. partnership, namely the alignment of U.S. and Jordanian strategic interests and the U.S. implementing security cooperation programs, activities, and initiatives determined as valuable by Jordan, resulted in the relative success of the JAF and U.S. security cooperation partnership over time
EXAMINING SOUTH KOREA’S HEALTH CARE UTILIZATION AND EXPENDITURE IN RESPONSE TO COVID-19 CRISIS: NAVIGATING WHAT'S NEXT
Get PDFThis dissertation presents a comprehensive analysis of healthcare utilization and expenditure in South Korea, examining the systemic transformations spurred by demographic shifts, economic changes, and the unprecedented COVID-19 pandemic. Through a tripartite framework derived from Donald Berwick's Triple Aim—improving the health of populations, reducing per capita healthcare costs, and enhancing the care experience—this work elucidates strategies for sustainable healthcare development amidst rising costs and shifting patient demographics.
The first study assesses the resilience of the healthcare system during the COVID-19 crisis through an interrupted time-series analysis. It investigates the variations in healthcare utilization patterns, particularly for vulnerable cohorts, and evaluates the effectiveness of pandemic management strategies in maintaining service levels. This manuscript not only highlights the adaptability of South Korea’s healthcare system but also underscores its capability to sustain essential healthcare delivery during global disruptions.
In the second study, the focus shifts to healthcare expenditures, analyzing both public and OOP spending. This manuscript offers a detailed exploration of expenditure dynamics across different demographics, diseases, types of payers and services, revealing increasing trends influenced predominantly by an aging population and a greater reliance on private insurance. The findings suggest critical areas for policy intervention, aimed at optimizing healthcare spending and potentially easing the financial burdens on both the system and its beneficiaries.
The final study proposes actionable strategies to manage escalating healthcare costs, influenced by demographic trends and the prevailing fee-for-service payment model. It advocates for significant system reforms, including changes to provider payment mechanisms and the enhancement of preventive care, aimed at improving financial sustainability and patient outcomes.
Overall, the dissertation provides a nuanced understanding of the complexities involved in healthcare management in South Korea, offering evidence-based recommendations for policymakers. The synthesis of these studies forms a robust foundation for enhancing healthcare efficiency, equity, and sustainability, guiding future strategic decisions in the face of ongoing and future challenges