15064 research outputs found
Sort by
Climate Policy at the Crossroads
Get PDFThis dissertation investigates the optimal design of international climate policy. Using Integrated Assessment Models (IAM) where countries differ in income, climate impacts, exposure to energy markets, and international trade, I analyze the optimal design of carbon taxation, climate agreements, and the spillovers of different climate policies, with an emphasis on redistribution motives. I first characterize the optimal taxation of carbon depending on the availability of international transfers. I show that when redistribution is limited, the uniform carbon tax differ from the Pigouvian First Best due to these redistribution considerations and general equilibrium effects on the energy markets. Moreover, optimal carbon pricing should vary across countries, with poorer and hotter countries facing lower carbon taxes than richer, colder ones. Second, I quantify the redistributive effects of unilateral and multilateral climate policies, highlighting the role of international trade in magnifying both the costs and spillovers of climate action. Through a sufficient-statistics approach, I decompose welfare effects across these different channels and map them into observable shares and measurable elasticities. I show that leakage effects from unilateral climate action are an order of magnitude larger than the direct benefits from emission reductions, emphasizing the necessity of global cooperation. Finally, I study the optimal formation of climate agreements, in the spirit of Nordhaus' "climate clubs", navigating a trade-off between carbon reduction at the intensive margin, and an extensive margin when countries can strategically free-ride and participation is endogenous. I find that the optimal climate club includes all countries except major fossil fuel producers such as Russia, Saudi Arabia, Nigeria, and Iran, implements a $110 carbon tax within the club, and imposes a 50% tariff on non-members to deter free-riding. I also explore the role of climate finance transfers, carbon tariffs, and trade retaliation on the feasibility and stability of climate agreements. Together, these results offer new insights into how climate policies can be optimally designed and coordinated across diverse economies to address the global challenge of climate change
Alien Residents: Immigration, Informal Law, and the Limits of Liberalism
No full textAlien Residents uses the history of the obscure “green card commuter status” to rewrite the history of 1960s immigration law, Mexican American political thought, liberal governance, and globalization. It is a socio-legal history of the green card commuter status — an administrative creation devised by the Immigration and Naturalization Service (INS) that allowed foreign nationals to enter the US as “permanent residents” for work on a daily or seasonal basis despite maintaining a permanent domicile in a contiguous foreign territory. Alien Residents shows how the state’s informal governance of the program effectively divided “Mexican commuter aliens” and “Mexican American” labor forces by producing competing, porous, and unstable rights claims while also eroding workers' access to the legal and administrative recourses they needed to defend them. With the advent of the Civil Rights Movement, liberals tried to resolve the entangled problems of Mexican American underemployment, Mexican poverty, and commuter migration by investing in borderland development and promoting tighter immigration controls. I argue that these policies inadvertently enabled agribusiness and borderland developers to evade 1960s racial and economic reforms by transforming commuters into de-facto guest workers and using the promise of cheap labor to entice neoliberal experimentation and private investment to the border, giving way to off-shore factories —maquiladoras. As a socio-legal, labor, and policy history, the project utilizes a wide range of sources, such as confidential state documents, legal cases, gossip, oral histories, economists’ reports, and other materials
Non-Invertible Symmetry in Lower Dimensional Gauge Theory
Get PDFThis thesis explores several applications of anyon condensation as a mechanism to characterize and implement non-invertible symmetries in gauge theories in two and three spacetime dimensions. First, we propose that the concept of level-rank duality can be understood in full generality by considering non-invertible symmetries as gauge symmetries, leading to a broad generalization of examples and a unified understanding of previously known examples. We also study the relation between non-invertible symmetries and the coset construction of 2D CFT. In particular, we describe topological cosets – defined by the case where the coset CFT has a vanishing central charge – and apply the results to find non-invertible symmetries of 2D QCD. In particular, this is used to describe the low-energy regime of 2D QCD and to constrain the energy spectrum of gapped 2D QCD. Finally, we use anyon condensation to argue for the existence of non-invertible one-form symmetry at the transition point of certain Chern-Simons matter RG flows triggered by the Higgs mechanism
Expanding Human and Computer Senses Through Perceptual Engineering
Get PDFThis dissertation proposes perceptual engineering as a new solution to longstanding challenges in sensory interface design. Perceptual engineering is a computational approach that systematically modulates human sensory mechanisms (such as thermal receptors, trigeminal nerve endings, and taste buds) to alter perception in controlled and reproducible ways. As computing moves beyond screens and into the body, designers face persistent limitations in engaging the full range of human senses. Modalities like smell, taste, temperature, and subtle touch remain underexplored in interactive systems due to their high power requirements, difficulty of miniaturization, and lack of sensory specificity. Perceptual engineering addresses these issues by targeting the physiological roots of perception, offering precise, low-power methods to create embodied sensory experiences. As the first technical instantiation of this framework, I introduce chemical interfaces: a new class of wearable systems that produce targeted feedback by interacting directly with the body’s chemical pathways. These systems exploit the potency and selectivity of safe chemical compounds to evoke haptic and thermal sensations as well as modulate gustatory sensations with minimal hardware. I demonstrate how chemical interfaces enable diverse applications: from delivering temperature illusions through trigeminal stimulation, to creating multi-sensation haptic feedback with a single actuator, to selectively suppressing or transforming specific tastes to promote healthier eating. Because they operate efficiently and can be miniaturized, chemical interfaces offer a practical path for integrating rich sensory modalities into everyday and immersive technologies. Building on this foundation, I extend perceptual engineering to include non-chemical forms of stimulation that share the same principles of direct, physiological modulation. For instance, I developed a stereo-smell interface that uses electrical stimulation of the nasal septum to generate lateralized chemesthetic sensations (subset of smell sensations), allowing users to localize virtual odors. I also designed a system that applies thermal feedback to the nose during inhalation, creating the illusions of inhaling more or less air—without changing actual airflow. These systems support new applications ranging from gas localization for safety (e.g., detecting odorless carbon monoxide leaks) and smell-based navigation to anxiety regulation and improved mask comfort. Together, these contributions define perceptual engineering as a generalizable foundation for future sensory interfaces. Unlike traditional approaches that simulate perception through audiovisual substitution or mechanical actuation, perceptual engineering enables compact, energy-efficient systems that engage the sensory body directly. This work lays the groundwork for interfaces that not only render sensation but give users agency over it: systems that allow people to actively shape what they feel, taste, or smell in response to context, preference, or need. Ultimately, this dissertation advances a broader vision: a future in which modifying perception (whether to improve health, enhance comfort, or deepen immersion) is as seamless and accessible as adjusting a phone's settings
Understanding the Dynamics of Clostridioides Difficile Infection in Human Gut Microbiomes Using Multi-Omic Approaches
Get PDFC. difficile, a spore-forming anaerobe, is a leading infectious cause of nosocomial diarrhea. The clinical outlook for C. difficile associated disease (CDAD) is highly variable and includes asymptomatic carriage, mild diarrheal illness, and pseudomembranous colitis. Symptomatic CDAD outcomes are associated with antibiotic-induced gut dysbiosis, so understanding the microbial ecology mediating colonization resistance against C. difficile may add valuable clinical context for infection control and treatment. The clinical use of multi-omic approaches, integrating shotgun metagenomic sequencing and metabolomic profiling directly from patient fecal samples, may have the potential to track the spread of and investigate the dynamics of C. difficile in real time. Despite this, the practical application of these tools in the clinic remains limited. As a step towards that goal, we optimized the powerful marker gene-based taxonomic profiling tool, MetaPhlAn4, and developed novel protocols for species level sensitivity tuning and strain-level C. difficile tracking. Using our locally optimized parameters, we investigated significant microbial and metabolic features discriminating CDI across diverse patient backgrounds. We then investigate the metabolic factors driving C. difficile inhibition by competing Clostridia spp. such as C. scindens, C. symbiosum, and C. sporogenes. Through these investigations, we observe strain-level variation in the inhibition of C. difficile by nutritional competition
Multi-Fidelity Active Learning for Efficiently Solving Inverse Problems
Get PDFInverse problems, where the objective is to infer input parameters from observed properties, are common across scientific and engineering disciplines. In the absence of analytical determinations or computationally efficient numerical approximations, solving an inverse problem often requires extensive computational resources to make observations from known input parameters and sufficiently explore the space of possible parameters. This dissertation proposes several novel multi-fidelity active learning approaches to help address this high computational cost while dynamically balancing trade-offs of accuracy and efficiency. The algorithms introduced fall into two broad categories. The first category of algorithms excels at interfacing with other AI-driven models to navigate through a large and complex state space to identify non-unique candidate solutions to inverse problems. The second category of algorithms excels at repeatedly selecting from within a more compact state space with the objective of identifying a unique, or near-unique, solution to an inverse problem. Taken together, we demonstrate that these algorithms can improve the navigation and multi-fidelity measurement capabilities of computational and experimental workflows to accelerate scientific discovery
Scripts and Stories: Collective Memory and Minnesota's HIV treatment landscape from 1990-2012.
No full textThe 1990s and early 2000s represented a pivotal period in HIV healthcare marked by the introduction of combination therapies which prompted shifts in healthcare infrastructure, expanded access, and new conversations about what it meant to live with the disease. Simultaneously, emergent discourses grappled with earlier legacies and mythologies of earlier HIV narratives while responding to the realities of new treatments, industrialized healthcare, and the continuation of fragmented access to resources. Together, these discourses reveal how HIV care in Minnesota was continuously shaped by the dialectic between sociocultural understandings and developments to healthcare. This thesis examines the production of HIV treatment from 1985-2012 in Minnesota. It focuses predominantly on the development of pharmaceuticals and changing healthcare landscapes, but also public health messaging, educational programs, and media discourse. It argues HIV must be understood as both a biological condition and complex social entity shaped by cultural, political, and economic systems. Focusing on the late twentieth and early twenty-first centuries, this thesis explores changing definitions of the disease and its treatment pathways as they dialoged with collective memories from earlier times of the epidemic
Beneath the Surface: United States Foreign Aid to Indonesia and the Aftermath of the September 30 Movement
Get PDFThis paper examines the decision-making process and motives behind the United States’ foreign aid to Indonesia during the 1960s, focusing on the period before and after the September 30 Movement. It aims to clarify how American foreign aid policies aligned with Hans J. Morgenthau's theoretical framework, which emphasizes political influence, national security, economic development, and ideological goals as the primary objectives of foreign aid. Using qualitative methods to analyze declassified documents, the paper maps the opposing policy considerations and compromises that shaped the United States' foreign aid decisions. Before the September 30 Movement, the United States reduced aid to pressure President Sukarno to end his Confrontation Policy against Malaysia and alignment with the Indonesian Communist Party (PKI). After the movement, United States aid increased to support the Indonesian military against the PKI in a covert manner to avoid negative publicity. The study reveals that the United States’ foreign aid policies were driven by a need to maintain a public image, bilateral relations, and national interests. These findings complement existing literature and demonstrate that United States foreign aid to Indonesia was a strategic tool to advance American interests, consistent with Morgenthau's theory
“Negociando” with New Neighbors: An Ethnography of English Language Instruction for Forced Migrants in Chicago
No full textThis project explores the integration challenges faced by forced migrants in Chicago, focusing on English language acquisition through a “New Neighbors” program. As Chicago experienced a significant influx of migrants, primarily from Venezuela, the city has struggled to provide adequate resources and support for these new arrivals. Using a combination of ethnographic methods and in-depth interviewing to examine the success and challenges of the program, this project documents the gap between program intentions and the realities faced by students and volunteers. I explore key themes including language acquisition, employment struggles, social integration, and the emotional impacts of forced migration. The study reveals that while language proficiency is crucial for employment and social inclusion, migrants face numerous structural and emotional barriers. Success stories, such as Maya securing employment and Daniel overcoming psychological hurdles, demonstrate the potential of culturally responsive education. However, systemic issues like job insecurity and legal barriers persist, emphasizing the need for comprehensive support systems beyond the scope of the program. I underscore the importance of integrating native language instruction with English learning, culturally relevant pedagogy, and community engagement to enhance migrant integration. I advocate for policy reforms to secure multi-year funding commitments and increased support from city, state, and federal agencies to more effectively assist Chicago’s newest residents
Where No Exhibition Has Gone Before: The Impact of the A More Perfect Union Exhibition
No full textA More Perfect Union was a revolutionary exhibition at the National Museum of American History that addressed Japanese American internment. The exhibition was part of the 1987 bicentennial celebration of the Constitution across Smithsonian Institutions. It also opened during the Redress Movement, when Japanese Americans were seeking reparations for internment. This monumental exhibition has been mentioned in multiple books; however, they often disagree about the exhibition and its impact. This is because none of them cited the Smithsonian Institution archives—except for one, who cited only a single accession. Despite this silence, the exhibition was cutting-edge due to its use of full-scale displays and AV technology, which allowed visitors to experience and hear interviews with victims of internment. A More Perfect Union’s impact extended beyond the walls of the museum and transcended time. The exhibition engaged with many movements and understandings of history. It had the same curator as the Enola Gay controversy and shifts our understanding of the “Culture Wars.” The exhibition also engages with our understanding of “prosthetic” memory, as it enabled the creation of a singular narrative of Japanese American identity, facilitated intergenerational bonding within the Japanese American community, and allowed other racial groups to construct their own memory of the incarceration. Interestingly, despite its importance it did not set a precedent leaving questions about our understanding of the shifting museum spaces