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The Center Cannot Hold: A Cultural History of the Emergence of the State in Early China
No full textThe development of a centralized and legalistic form of statecraft in the state of Qin is often taken to be representative of the political changes that occurred during the Warring States (475-221 BCE) period, and of the Chinese political tradition as a whole. In order to complicate this view, this dissertation draws on a wide array of received and excavated texts to reconstruct the sociopolitical importance of gift-giving in early China, both as praxis and in terms of the political and social imaginary. Gift-giving rituals were central both to the mutual recognition of sovereign and subject, and the attempt to propose an emic set of norms surrounding gift-giving in terms of ritual li 禮. The social logic of the gift, which demanded reciprocation, situated material goods and services within a decentralized web of ongoing human relationships and promoted a discourse of altruism (which in reality was often driven by self-interest). At the same time, it gave both lords and local communities the power to negotiate and manipulate social and juridical realities. This framework existed in immense tension with the Qin legal order, which sought the rigid classification of people, property, and actions; promoted a discourse involving the direct pursuit of self-interest; and ultimately became a vehicle for the ruler to monopolize all forms of political gift-giving. As the state of Qin expanded, it created an institutional structure to ensure the uniform interpretation of the law and overcome the resistance of intellectuals who tried to assert an independent hermeneutic authority. At the same time, the state of Qin’s broad application of the legal concept of “theft” dao 盜 became important as a means of defining the rights and duties associated with state and private property. As a noun, dao also became the term for rebels, bandits, and other enemies of the state who were excluded from the political community defined in terms of the gift. Qin Shihuang drew on the rhetoric of the gift to justify his rule, but many Han intellectuals criticized the brutal expropriation that characterized his reign. In contrast, Liu Bang, the rebel dao 盜 who established the Han dynasty, was successful in large part because he and his successors restored the centrality of gift-giving to the political order. In reexamining early criticism of the authoritarian political model of the Qin dynasty in relation to the broader political, intellectual, and legal context of early China, this dissertation offers a new perspective for understanding and theorizing both the legitimization and critique of state power in later periods of Chinese history. At the same time, by drawing on Marcel Mauss to explore the centrality of gift-giving to the political order, it complicates understandings of Chinese officialdom rooted in Weberian conceptions of impersonal bureaucracy.East Asian Languages and Civilization
Criticality, fractionalization, and superconductivity in two-dimensional quantum materials.
Get PDFEmergence is a foundational concept in modern condensed matter physics, capturing the idea that interactions between many degrees of freedom can give rise to phenomena that have no analog at the level of individual constituents. Superconductivity stands as one of the most celebrated exam- ples of emergence, where electronic correlations give rise to a macroscopically observable coherent quantum-mechanical state. More recent developments in the field include the study of emergent gauge theories, which describe the highly entangled states of matter that can appear in frustrated and strongly interacting systems. As increasingly exotic phases of matter are discovered, a deeper understanding of how strong correlations give rise to these phases and the transitions between them becomes essential.
In this dissertation, we will explore the concept of emergence in the context of two-dimensional quantum materials. In the first part, we will discuss the exotic phenomenology of high-temperature cuprate superconductors and present a theory for a fractionalized parent state of superconductivity. We will describe how such a parent state can account for several experimental observations made in both the superconducting and charge-ordered phases. We will describe how our normal state can be understood as an emergent gauge theory, with possible applications to the study of deconfined critical points. Furthermore, we will study the critical properties of out theory through a renormal- izationgroupN1 analysis.
We will also explore the strange metallic phase of the cuprate superconductors, presenting a study at large M of a simplified, zero-dimensional model that captures the spin glass phase observed at low doping, the Planckian metal phase near criticality, and the Fermi-liquid-like phase at high doping. Additionally, we will examine the 1/M corrections demonstrate that they always lead to spin glass ordering at low doping.
In the final part of this dissertation, we will discuss several examples of superconducting and in- sulating phases observed in moiré materials. First, we will investigate the possibility of deconfined criticality in twisted bilayer graphene and identify the potential superconducting pairing states com- patible with a direct second-order transition between the superconductor and insulator. Next, we will present a mean-field analysis of insulating and superconducting instabilities in several stacked van der Waals materials. We will further discuss the consequences of inter-band coherence on ob- servables in the superconducting state.Physic
Toward Personalized Stroke Rehabilitation in the Community With a Mobile FES Neuroprosthesis
No full textAs the field of lower-limb assistive technology advances, there is growing interest in shifting gait rehabilitation from controlled clinical environments to community-based settings, aiming to enhance motor recovery through increased training dosage, intensity, and ecological validity. Functional electrical stimulation (FES) neuroprostheses targeting plantarflexion have emerged as promising tools to support gait rehabilitation by activating biological muscles directly, thus promoting neuroplasticity and yielding improvements that persist beyond active stimulation. However, existing FES systems primarily rely on preset stimulation patterns and controlled clinical conditions, limiting their real-world applicability, adaptability, and long-term effectiveness.
To address these limitations, this thesis presents the development and evaluation of a mobile FES neuroprosthesis designed to provide personalized push-off propulsion and ground clearance assistance, two deficits widely observed in individuals post-stroke. The mobile platform enables adaptive control based on biomechanical responses and user preference, supported by wearable sensing frameworks to enable longitudinal monitoring and tuning in community settings.
The first aim introduces the mobile FES system and demonstrates its capability to provide targeted stimulation during overground walking with stroke survivors. Through a series of technical pilot studies, we highlight critical design considerations for community deployment, including coordinated stimulation of dorsiflexion and plantarflexion, personalized control using biomechanical inputs, and management of physiological phenomena such as electromechanical delay and fatigue. Using this system, we explored the biomechanical effects of overground walking with FES, finding both immediate and short-term retained benefits, highlighting its potential to meaningfully enhance daily function and quality of life. Notably, optimal stimulation timing varied considerably between individuals, underscoring the necessity for personalized tuning to maximize biomechanical improvements and avoid exacerbating gait impairments.
Building on these findings, the second aim investigates strategies for personalizing FES while balancing multiple competing objectives, including biomechanical effectiveness, comfort, and long-term adherence. We developed a multi-perspective personalization framework combining user preferences and biomechanical performance metrics. Interestingly, we observed that clinicians, who are often tasked with tuning and prescribing these devices, largely favored visible kinematic changes over critical kinetic features essential for effective propulsion. This finding suggests that human perception alone may be insufficient for optimal tuning and reinforces the need for objective biomechanical guidance that can ensure better clinical outcomes and more effective gait rehabilitation.
The final aim focuses on addressing this gap by establishing estimation frameworks that use wearable sensing, such as inertial measurement units and pressure insoles, to provide accurate kinetic estimates for populations with neuromotor gait impairments outside laboratory environments. These methods lay the foundation for future expert-informed and automated device tuning, and facilitate comprehensive real-world monitoring of gait biomechanics. Furthermore, we demonstrated the feasibility of integrating these wearable-derived kinetic variables as inputs into adaptive control algorithms for wearable devices, including the mobile FES platform and an ankle exoskeleton, representing a meaningful step toward practical community deployment. Additionally, we investigated methods combining electrical stimulation with ultrasound imaging to reliably track muscle fatigue, offering an initial step toward characterizing muscle states in real-time and providing feedback to enable safe assistance that could respond to the onset of fatigue.
Collectively, this thesis lays important groundwork toward achieving scalable, personalized, and clinically impactful gait rehabilitation in everyday community environments through a multifaceted approach that combines portability, user-specific adaptation, and biomechanics-informed control.Engineering and Applied Sciences - Engineering Science
Born-Frees, the Matric Exam, and the Battle Royale for Opportunity in South Africa
Get PDFEvery year, around a million South African grade twelve learners sit for the National Senior Certificate Examination, colloquially called “matric.” Widely understood as a significant determinant of a young person’s future, it acts both as a school exit exam and a university admissions test. Rooted in the colonial bureaucracy of the mid-1800s, the matric exam has evolved into a national obsession and a central mechanism through which the postapartheid state has sought to signal equality of opportunity. In principle, everyone answers the same questions under the same conditions. Yet, despite the steady rise in candidates and the national pass rate, the exam increasingly functions as a high-stakes selection apparatus in a context of deep inequality and widespread exclusion. As youth unemployment reaches staggering levels, and university spaces remain limited, passing the exam no longer guarantees access to work or further study. The competition for scarce, desirable futures has
become fiercer than ever.
In this dissertation, I explore how competitive stratification has come to coexist with an ethos of equality, and what that means for a generation of born-frees coming of age after apartheid. I draw on thirteen months of ethnographic fieldwork in a Western Cape town, where I followed learners at three public high schools as they prepared for the 2021 exam. The matric exam produces both aspiration and anxiety. While some learners remain committed to the belief that education offers a pathway to a better future,
others express doubt, ambivalence, or quiet withdrawal. For many, schooling retains a near-salvific promise—even as the prospects of social mobility diminish. I argue that the exam has come to encapsulate what it means to be young in South Africa
today: it marks a broader shift in which collective visions of liberation are being displaced by individual strategies of advancement. For born-frees still waiting for their share of democracy’s rewards, opportunity is not assured—it is conditional,
competitive, and increasingly out of reach.African and African American Studie
GeopoliticalStrength in Religious Ties: How Diplomatic Relations Between the Vatican and Post-Revolutionary Iran have Bolstered Iranian Resilience
Get PDFNumerous players influence those at the helm of the global political stage. Yet dominant state powers, especially democratic ones, remain at the forefront. They set the tone, reshape borders, dictate trade, and attempt to instill peace in times of instability and turmoil. In the today’s world, where information is immediate and no global event is “unsearchable,” traditional rules are no longer uniplanar as to what international relations and diplomatic means may drive intrastate dialogue and change. Unlikely players can hold immense power.
This thesis outlines one salient example of significant impact relating to relations between two unique, noncentral players: the Islamic Republic of Iran, and the Holy See (herein referred to as “the Vatican”). At face value, most would not think that these two bodies share much in common. Beliefs, social norms, and political disposition vis-à-vis the rest of the world, are vastly different. Yet, upon deeper inspection we find many similarities, shared beliefs, common causes, and appreciation for what each represents. Importantly, both entities hold significant political and spiritual power over their citizens and adherents.
Contrast this with the most powerful political authority on Earth, the United States. Hailed for democracy and freedom fighting, feared for its mighty military, and envied for its development and wealth, the U.S. sits at the top of all global powers. But this position comes with immense responsibility and expectations. Not only is the U.S. expected to assist in maintaining global stability, but the democratic values of the country’s leadership and its citizens empower it to export democracy to all who will listen and even to those who will not. While sentiments had been building for decades, the terror attacks of September 11 exacerbated intolerance for dissimilar players. If you are not democratic, it is difficult to be viewed positively by the U.S., however it is the right of individual nations to determine what political structure will bind them and that democracy is not always the choice. Some nondemocratic entities are benign, such as the Vatican, while others present an adversarial threat to democracy, for example, postrevolutionary Iran. Ironically, these two are similar politically in that they both follow theocratic principles. But one heads a list of top five foreign policy priorities and threats to the U.S., and the other heads a list of friends, eager to be engaged in times of needed counsel.
Through this thesis, I will show how the U.S. and the Western world find relations with the Vatican useful when convenient. On the other hand, I will outline how a deeper, religious bond between the Vatican and Iran has come to supersede the mere diplomatic relationship between the U.S. and the Vatican. I will explain how Vatican– Iranian relations have yielded unexpected gains for Iran and have bolstered their political body when most of the world has stood against them.Extension Studie
Listening to Andean Idolatry Trials: 1650-1680
No full textIn this dissertation, I read with open ears the witness testimonies of the seventeenth-century idolatry trials filed under the section "Visitas de Hechicerías e Idolatrías" at the Archive of the Archbishopric of Lima, attending to the vibrant traces murmuring between the lines, engaging in exercises of reconstruction that build sound from silence.
I offer the earliest reconstruction of a non-notated Quechua song, overviews of funerary sound practices, rethatching ceremonies, dancing rituals, sacred landscapes and ancestral journeys, as well as the first known historical documentation of the usage of whistling bottles.
I reflect on the impossibility of communicating vibrancy through the written word, on the foolery of trusting archival sources as pillars of truth, and on the fruits of engaging with the fiction of the native perspective—a naïve intention of understanding history outside of colonial agendas and systems of signification, embracing instead questions and worldviews I perceive as relevant in the long history of Andean ritual.
I construct historical narratives using a variety of vocabularies, materials, and approaches to the archive, seeking to challenge the seeming transparency and authority of archival constructs of truth and disciplinary objects of study. I mold clay to study history, circumventing the colonialist silence imposed by the symbolic systems of signification in which archival sources are inscribed. My listening rests on a site of impossibility, which I challenge by foolishly opening my ears to the ancestral voices that enlightened faculties of truth deem impossible and colonial powers sought to demonize and silence.Musi
Ecological Activities in Childcare Microbiome
No full textThe field of human and environmental microbiome research has undergone remarkable growth over the past two decades, driven by technological innovations that allow us to characterize complex microbial communities without traditional culture-based approaches. Despite these advances, several fundamental challenges persist: terminology inconsistencies that hinder communication among microbiome researchers, incomplete characterization of microbial transmission dynamics in key developmental settings like childcare centers, and difficulty distinguishing viable from non-viable microorganisms in community samples. This dissertation addresses these interconnected challenges through three distinct yet complementary investigations that collectively advance both the technical foundations and applied aspects of microbiome science, with particular attention to early-life exposures in built environments where children spend significant portions of their developmental years.
Chapter 1 examines the evolving lexicon of microbiome research, highlighting how inconsistent terminology has created confusion in the field. Through critical analysis of common terms like "microflora" and "metagenomics," we demonstrate how shifting definitions and misapplications have complicated research interpretation. The chapter provides a structured review of computational strategies for microbiome data analysis, distinguishing between taxonomic and functional approaches derived from various meta'omic methods. By organizing and clarifying vocabulary for major classes of microbiome analysis and their resulting feature tables, this work establishes a framework for more precise communication, enhancing the field's ability to address specific questions about microbial community composition and function with appropriate methodological alignment.
Chapter 2 applies advanced multi-omic techniques to investigate microbial transmission in childcare facilities—critical environments where young children experience formative microbial exposures during immune development. This represents the first comprehensive study integrating microbiome samples from childcare environments and children using full-length amplicon sequencing and both short-read and long-read metagenomic approaches. The findings reveal distinct environmental microbial signatures, with human-associated microorganisms predominating on high-touch surfaces while greater taxonomic diversity characterizes low-touch areas. The identification of transmission pathways between children and their environment, including food-associated microbes like Lactococcus lactis and Streptococcus thermophilus, provides insights into microbial exposure routes during early development. Additionally, the improved genomic resolution afforded by paired sequencing technologies enabled detection of lateral gene transfer events and characterization of bacteriophage ecology, highlighting how enhanced methodological approaches can reveal previously understudied aspects of environmental microbiomes.
Chapter 3 addresses the fundamental challenge of distinguishing viable from non-viable microorganisms in complex communities. This work develops a novel, high-throughput approach based on sequencing multiple optimized marker gene transcripts to identify actively transcribing microbes. Through rational marker gene selection, in silico primer design, and optimized amplification protocols validated against paired metagenomic and metatranscriptomic datasets, the method provides an accessible alternative to more costly and technically demanding techniques. The resulting protocol demonstrated effectiveness in distinguishing viable microbes across synthetic, human, and built environment samples, offering a scalable solution for identifying and quantifying functional community members in diverse microbiome samples.
Together, these chapters represent a comprehensive contribution to microbiome research methodology and application. By addressing terminological precision, environmental context, and viability assessment, this work provides a foundation for more rigorous and biologically meaningful microbiome studies with applications spanning environmental monitoring, clinical diagnostics, and public health interventions.Population Health Science
Investigating Differential Binding Stabilities of MHC-E Restricted Epitopes in SIV Vaccination
No full textHIV continues to pose a global health challenge and has prompted extensive research into exploring effective vaccine strategies. Previous breakthroughs in simian immunodeficiency virus (SIV) vaccine development using a rhesus CMV vector recombinant for SIV antigen (RhCMV 68-1/SIV) showed unprecedented sterile immune clearance against SIV challenge.
Subsequent studies sought to determine the underlying mechanism of protection in this promising prophylactic vaccine strategy. An unconventional, MHC-E-restricted subset of CD8+ T cells was identified and shown to be necessary for protection. However, RhCMV 68-1/SIV vaccine-identified SIV epitopes identified by Hansen et al. lack canonical primary anchor residues, present low or negligible binding to human HLA-E, and thus do not support stable HLA-E/B2M complex formation. This inconsistency raises questions about their role and functionality in RhCMV 68-1/SIV vaccination. We therefore performed a comprehensive and direct comparison of SIV peptide binding to human and rhesus MHC-E. This thesis study aims to evaluate the binding characteristics and stability of RhCMV 68-1/SIV vaccine-identified SIV epitopes in complex with a panel of rhesus macaque and human MHC-E orthologs, specifically Mamu-E*02:04, Mamu-E*02:11, and HLA-E*01:03. The objective is to validate whether these SIV epitopes demonstrate comparable binding to Mamu-E and HLA-E, or if there is enhanced stability for Mamu-E as opposed to HLA-E. If the latter holds true, with Mamu-E exhibiting superior stability in complex with vaccine-identified SIV epitopes, it could explain the mechanism of vaccine efficacy but indicate challenges in translating this vaccine success to human clinical applications. If Mamu-E and HLA-E show similar binding to RhCMV 68-1/SIV vaccine-identified SIV epitopes, then alternative mechanisms of vaccine-mediated protection should be explored. To accomplish these goals, Mamu-E and HLA-E were recombinantly expressed in prokaryotic expression systems and refolded to form MHC-E/B2-microglobulin complexes prior to performing in vitro SIV peptide loading reactions. Thermostability assays using Differential Scanning Fluorimetry were conducted to compare the stability of Mamu-E and HLA-E complexes in the presence of excess SIV peptides. By examining the interactions between the vaccine-identified SIV epitopes and MHC-E molecules, this study aims to clarify the underlying mechanisms of the observed vaccine efficacy thereby facilitating its translation into the human clinic. Our findings reveal that the majority of vaccine-identified SIV epitopes do not stabilize either Mamu-E or HLA-E alleles. Given this weak or insignificant stabilization, it is likely that direct presentation of vaccine-identified SIV epitopes by MHC-E is not the primary mechanism of protection introduced by RhCMV68-1/SIV vaccination.Graduate Educatio
Novel drivers of eukaryotic protein biogenesis and complex assembly
Get PDFThe cell’s capacity for protein folding can be controlled by transcriptional regulation of genes encoding chaperones. These factors recognize unfolded proteins to shield them from aggregation or actively assist their folding process. Protein synthesis is an intrinsic folding burden on the cell that is monitored by the heat shock (transcription) factor 1 (Hsf1) to maintain the appropriate expression of a small number of essential chaperones for general protein folding. The starting point for my first body of work was the lab’s observation that Hsf1 in the yeast S. cerevisiae additionally controls expression of Zpr1, a protein that bears no homology to other chaperones but is essential and conserved across eukaryotes and archaea. Using complementary approaches, including biochemical reconstitution and structure-guided mutagenesis, we found that Zpr1 is a chaperone tailored to the final steps in the biogenesis of eukaryotic translation elongation factor 1A (eEF1A), a highly abundant GTP-binding (G) protein comprising ~5% of the proteome. The extreme fragility of eEF1A’s tertiary structure had been historically appreciated since the 1970s, when eEF1A’s biochemical activity was first characterized. Our work explained how cells efficiently solve this problem to enable rapid growth while staving off the inherent potential of abundant eEF1A folding intermediates to disrupt global protein folding in the cell.
My subsequent work was centered on the identification of two additional factors in yeast, both conserved but uncharacterized, that support eEF1A biogenesis. First, we identified Aim29 by forward genetic screening as a factor that promotes Zpr1’s essential function in the cell. Follow-up work by other lab members showed that Aim29 is a co-chaperone for Zpr1 that facilitates substrate release once eEF1A has acquired the ability to hydrolyze GTP. Second, using an AlphaFold-guided computational screen, we predicted the function of Ypl225w as a chaperone dedicated to folding eEF1A’s N-terminal G domain. Using a myriad of assays, we found that Ypl225w associates with ribosomes in the act of synthesizing short eEF1A nascent chains. Ypl225w then remains stably bound to translating ribosomes until the emergence of the full complement of GTP-binding sequence elements within the G domain of eEF1A. Lastly, GTP binding to nascent eEF1A drives G domain folding while triggering release of Ypl225w, thereby allowing chaperone recycling. Together, this body of my thesis work revealed that cells use a dedicated team of folding factors to guide eEF1A’s biogenesis beginning with its nascency on the ribosome. By contrast to general chaperone ATPases, eEF1A ATP-independent chaperones receive cues about biochemical directionality and folding product quality via GTP binding and hydrolysis of their sole client.
Next, we focused on identification of an assembly factor for the eukaryotic chaperonin TRiC/CCT. Chaperonins are large, ring-shaped complexes that mediate folding of proteins inside their nanocages. The cytoskeletal protein tubulin is an obligate CCT folding substrate that undergoes a series of sequential folding steps while being encapsulated. Each of these steps comprises a stereotypical interaction with one of eight paralogous CCT subunits that exist in a defined spatial arrangement relative to one another. Since individual CCT subunits lack inherent information for correct self-assembly, we used AlphaFold-guided computational screening to identify the missing assembly factor(s). We show that a conserved tubulin-like protein (Dml1 in yeast) functions as a CCT substrate mimic to guide the association of the positively-charged half-ring of subunits, namely Cct6, Cct3, and Cct1. Using an electrostatic hook, Dml1 next links Cct1 to the negatively-charged half-ring of subunits via Cct4, which arrives at this junction associated with subunits Cct2, Cct5, and Cct7. Finally, we show that Dml1 is required for the association of Cct8 to Cct6, marking the closing of the chaperonin rings en route to CCT complex maturation.Biology, Molecular and Cellula
Smart Glasses to Monitor Intermittent Exotropia
Get PDFAcross the world, an estimated one percent of the population experiences intermittent exotropia, a condition in which one eye occasionally drifts outwards independent of the other eye, which often unknowingly occurs while tired, sick, or daydreaming. In this thesis, a pair of smart glasses are presented which allows for accurate and quantitative monitoring of the angle of deviation of both eyes. This pair of smart glasses preserves the look and feel of a conventional set of glasses, making efforts to minimize size and weight, but also enabling angular eye tracking. This solution is unique in that it takes advantage of edge computing to perform angular inferencing onboard the frames of the glasses themselves, allowing for an all-in-one solution that does not require being connected to a separate phone or computer for computational inferencing. This project also has possible future applications in virtual reality control, computer input, marketing research, and accessibility improvement.Engineering Sciences A