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INVESTIGATING PRECISE MANAGEMENT AND ARRHYTHMOGENIC MECHANISMS IN GENETIC HEART DISEASE USING CLINICAL DATA AND HEART DIGITAL TWINS
No full textArrhythmogenic right ventricular cardiomyopathy (ARVC) is a genetic heart disorder that predisposes individuals, particularly young and athletic populations, to ventricular tachycardia (VT) and sudden cardiac death. Despite advancements in medical technologies, managing ARVC remains a significant challenge in clinical practice. Catheter ablation, a primary treatment for VT in ARVC, is associated with high recurrence rates. Although ARVC encompasses various genetic subtypes, each with distinct disease mechanisms, current management strategies largely adopt a one-size-fits-all approach, reflecting an incomplete understanding of genotype-specific differences. This thesis addresses these challenges by investigating personalized management strategies for ARVC patients and elucidating the underlying arrhythmogenic mechanisms. Through the development of a genotype-specific digital platform that integrates genetic information, clinical data, and biophysical heart models, we successfully predicted VT circuits and optimal ablation sites. Furthermore, this platform revealed critical genotype-specific differences in arrhythmogenic mechanisms. The innovations described in this thesis lay the foundation for advancing precision medicine and enabling more personalized management of cardiac diseases, ultimately improving patient outcomes
Rhythm To Recovery: A Bench-To-Bedside Heart Rate Variability Framework For Neurological Outcome Prediction After Sudden Cardiac Arrest
No full textSudden cardiac arrest (SCA) is a major cause of death and long-term brain injury. For patients who survive the initial event, neurological damage evolves rapidly in the hours following resuscitation. Yet during this critical window, reliable tools to assess brain recovery are often unavailable. Conventional methods such as EEG and neuroimaging are delayed, limited by sedation, or not feasible at the bedside. This creates a gap where fast, physiology-based indicators could guide treatment and improve outcomes.
This thesis explores heart rate variability (HRV), a non-invasive measure of autonomic nervous system activity, as an early marker of neurological recovery after SCA. The central hypothesis is that changes in HRV reflect brain function during early recovery and can support outcome prediction before traditional assessments are available.
The research follows a stepwise, translational approach. In preclinical rodent models, HRV features recorded within the first hour after resuscitation are shown to distinguish recovery trajectories. New feature extraction methods are developed to capture autonomic patterns linked to neurological outcomes. The framework is then expanded to include blood pressure and ECG signals routinely collected in intensive care units. By combining these inputs, the model improves predictive accuracy and reveals distinct physiological recovery patterns. Next, the system is applied to a clinical cohort of patients receiving extracorporeal life support after cardiac arrest. Despite the complexity of ICU conditions, HRV features remain measurable and correlate with neuroimaging findings and discharge outcomes, reducing prediction time by nearly half. To support real-world deployment, a wearable ear-based ECG system is developed, incorporating a modified adaptive filtering method to ensure high-fidelity ECG monitoring in noisy clinical environments, enabling reliable downstream HRV analysis. Finally, a proof-of-concept platform is introduced in which HRV monitoring is paired with non-invasive vagus nerve stimulation to explore real-time, closed-loop intervention strategies.
In summary, this work presents a clinically adaptable approach to early brain monitoring after cardiac arrest. By combining non-invasive signals, interpretable analysis, and wearable technology, it offers a practical solution to bridge the early neuroassessment gap in time-critical and resource-limited settings
Digital Preservation and its Environmental Impact The Effect of Digital Preservation on the Environment and Potential for Organizational Change
Get PDFDigital preservation is a process that inherently contributes to the ongoing climate crisis through its use of electronics and electricity. This paper seeks to answer the following: what is the current environmental impact of digital preservation in the United States? Are cultural heritage organizations (CHOs) aware of the impact of digital preservation on the environment? What adjustments are CHOs willing and able to perform in order to reduce the impact of their digital preservation and how can CHOs be made aware of the need for and techniques to reduce the impact of digital preservation? It achieves this through a review of the literature and a series of interviews with cultural heritage professionals. Findings indicate that the current impact of digital preservation is similar to how it was five years ago. CHOs were found to have minimal awareness of the impacts of digital preservation on an organizational level, but were willing and able to enact a number of changes to reduce their impact, depending on size and location. Finally, it was determined that awareness of the effects of digital preservation and feasible solutions need to be raised more intensely through community channels
ESSAYS IN EMPIRICAL INTERNATIONAL FINANCE
No full textThis dissertation consists of three essays on exchange rates, focusing on the role of unconventional monetary policy, credit risk, and uncertainty across emerging markets and advanced economies.
The first chapter evaluates the impact of COVID-era asset purchase programs (APPs) on the dollar exchange rate in both emerging markets (EMs) and ex-U.S. advanced economies (AEs). Using an event study framework with APP announcements from 23 EMs and seven AEs, I find that APPs lead to an appreciation of EM currencies, even after accounting for U.S. Federal Reserve policy actions, swap lines, and domestic policy measures. These results suggest that APPs might help EMs stabilize exchange rates during episodes of distress without necessarily intervening in the foreign exchange market.
The second chapter examines the validity of long-run uncovered interest rate parity (LRUIP) in EMs. While LRUIP is often found to hold for G10 currencies, we show that it fails for EM currencies. However, when controlling for credit risk, LRUIP cannot be statistically rejected for the most freely floating EM currencies, highlighting the role of sovereign risk in driving interest rate differentials and exchange rate dynamics in EMs.
The third chapter studies the effects of geopolitical risk (GPR) and trade policy uncertainty (TPU) shocks on bilateral exchange rates against the U.S. dollar using a panel local projection framework from 1985 to 2025. We document strong threshold effects, where large global GPR shocks cause AE currencies to depreciate and country-specific GPR shocks and TPU shocks result in sharper and more persistent depreciations in EM currencies. These findings highlight the non-linearity of GPR and TPU shocks and their differential impacts across country groups
ESSAYS ON MICROECONOMIC THEORY
No full textThis dissertation presents three essays on consumer and firm behavior, with a particular focus on integrating bounded rationality. The first paper develops a list-based random attention model to study how stochastic limited attention affects decision-making when an agent selects one item from an ordered list of alternatives. The model attributes stochastic choice to variations in the number of items considered by the agent, which may differ across lists. I show that a finite dataset of lists’ choice distributions can be rationalized by the model if and only if these distributions satisfy two testable conditions. When the choice distributions are rationalizable, both conditions convey information on the agent’s unobserved attention behavior and preference. As an application, I explore how a list designer can construct a list of alternatives that maximizes worst-case profit, given partial information (extracted from the data set) on the agent’s attention behavior and preference. The second paper introduces revealed preference tests for the profit-maximizing behavior of a monopolist producing either a single good or multiple goods. The tests impose no parametric assumptions on the firm’s production or demand functions. I characterize when observed market outcomes are consistent with profit maximization, allowing for both time-invariant and time-varying demand functions, whether known or unknown to the modeler. I then propose a revealed preference test for Bertrand-Nash equilibriua among firms producing differentiated goods. The third paper presents a model where some consumers pay only limited attention to the good on offer and may choose not to consider a product for purchase simply because of its price, without considering its net utility. We study the implications of this type of bounded rationality on firm behavior in both a monopoly market and a duopoly market
“A SURVIVAL ISSUE”: TRANSATLANTIC CITIZEN OPPOSITION TO URBAN TRANSPORTATION PLANNING, 1960s-1980s
No full textThis dissertation examines citizen opposition to urban transportation planning from a transatlantic perspective. From the 1960s to the 1980s, activists in Western European and North American cities organized to stop the construction of new transportation infrastructure—initially freeways and other automotive infrastructure, but subsequently also rapid transit lines. The dissertation analyzes these waves of activism as a semi-coherent, transatlantic social movement—one that emerged against the backdrop of the urban issues that plagued American and European cities in these decades. In both Western Europe and the United States, journalists and historians tend to celebrate the ‘freeway revolts’ and, later, the anti-transit activism of the 1960s and 1970s as heroic, grassroots fights to promote more democratic urban planning mechanisms, to protect the environment, and to preserve historic architecture. With examples from cities across the United States and Western Europe, I show, in contrast, that these activists were not merely idealists. Often, they were first and foremost concerned with their own financial security and the stability of their communities. Resistance to freeways—and later to rapid transit infrastructure—was a struggle, not for idealistic principles, but for survival.
In the 1960s and 1970s, cities in Western Europe and America faced population decline, deindustrialization, political tensions, and physical decay. Urban housing markets were volatile, and demographic changes and their associated racialized fears further contributed to a widespread sense of neighborhood instability. Activists mobilized against transportation infrastructure because they symbolized the very real threat of neighborhood collapse and community disintegration. For these residents, moralistic arguments steeped in environmental science and opposition to technocratic governance and modernist architecture became a potent political and rhetorical tool—an instrument rather than a primary motivation. In several cities, activists also produced a narrative about citywide racial and class harmony in opposition to freeway and transit plans and government writ large—a narrative that has similarly come to characterize popular and scholarly accounts. The reality was more complex; when interests converged, activist coalitions across race, class, and neighborhood did form in certain cities. More commonly, however, urban transportation infrastructure plans pitted political districts, neighborhoods, and groups against each other
HETEROGENEOUS DEPOSITION OF CHARGED PARTICLES VIA PARTICLE-TURBULENCE INTERACTIONS
No full textParticle deposition through turbulent boundary layers onto substrates is a fundamental process relevant to diverse applications such as aerosol drug delivery in the respiratory tract, particulate removal in air filtration systems, and fouling in gas turbines. Despite decades of research, critical gaps remain in our understanding of how inertial particles deposit, redistribute, and accumulate over time—particularly under the influence of electrostatic forces and turbulent flow structures. To address these unresolved issues, we performed deposition experiments in a vertical electrostatic turbulent channel equipped with a particle charger and a custom measurement section featuring transparent conductive walls. This setup enabled control over the electrostatic attraction of particles to the wall. A suite of synchronized diagnostics was employed to obtain a comprehensive view of the deposition process: Lagrangian particle tracking in both wall-parallel and wall-normal planes captured particle transport and impact dynamics, a projected image distortion technique reconstructed deposit topography in situ, and Faraday cup sensors provided direct, quantitative measurements of particle charge. The deposition process exhibits three distinct regimes. Initially, sparse deposits nucleate along low-speed streaks near the wall, guided by the spatial organization of coherent turbulent structures and enhanced by electrostatic attraction. In the subsequent expansion phase, these deposits grow laterally across the wall, increasing in area while maintaining relatively low and uniform height, indicating that particles continue to deposit primarily along the edges. In the final regime, adjacent deposits coalesce into continuous band-like structures, interspersed with clean regions. These persistent gaps arise due to aerodynamic shadowing, where existing deposits alter the near-wall flow and deflect incoming particles, suppressing further deposition downstream. This study presents a detailed, experimentally grounded picture of charged inertial particle deposition in turbulent boundary layers. By resolving the growth dynamics, spatial heterogeneity, and coupling between turbulence, particle inertia, and electrostatics, this work provides new insights into long-standing questions about deposition behavior in realistic flow environments
FROM CLASSROOM DESIGN TO PEDAGOGICAL SUCCESS: ENHANCING TEACHERS’ ENVIRONMENTAL COMPETENCE AND EFFECTIVE TEACHING PRACTICES
Get PDFThe physical learning environment (PLE) is a valuable yet often overlooked educational resource that can shape student learning outcomes and pedagogical goals. Despite a growing body of research that affirms the impact of PLEs on student engagement and academic performance, many teachers lack the knowledge, confidence, and support to fully leverage their PLEs. This dissertation explores the concept of teacher environmental competence, a teacher’s ability and confidence to maximize the PLE for pedagogical effectiveness.
Anchored by Bronfenbrenner and Morris’s (2007) PPCT model, a comprehensive literature review explores the interaction between teachers and their PLEs, uncovering factors that influence the teachers’ environmental competence, including: culture, competition, historical design constraints, and teacher knowledge and beliefs about PLEs. Based on the literature review, a needs assessment conducted at an independent school employed a mixed-methods approach to assess teachers’ environmental competence. Findings from a facilities survey, focus group discussion, open-ended questionnaire, and Likert-scale question indicated that while teachers articulate the importance of PLE design, constraints such as limited training, funding, time, space limitations, and lack of institutional policies impede their ability to implement best practices. The needs assessment findings and a second, targeted literature review on teacher professional growth, broadly, and teacher use of learning spaces, specifically, informed development of a professional development (PD) proto address the gap between what teachers say and what they do with regard to their learning environments.
Drawing on research suggesting the inclusion of key design components critical for professional development to have a lasting impact on teachers’ professional practice, a year-long, cohort-based professional development program was designed with the focus of increasing teacher environmental competence. Key components of the program, illustrated in full, include action research, peer collaboration, one-on-one coaching, and structured reflection. The dissertation provides a detailed overview of the PD exemplar, including session outlines, learning activities, accompanying materials, video resources, and assessment tools. In the final section, a personal reflection on the product and process describes key insights that emerged during the design, including the role of teacher agency, contextual relevance, and inquiry as critical drivers of meaningful change in teacher environmental competence
A DEAD-BOX RNA CHAPERONE AND LIQUID-LIQUID PHASE SEPARATION COORDINATE RIBOSOME ASSEMBLY
No full textRibosome assembly is coupled with transcription of the pre-rRNA. In vitro, co-transcriptional ribosome assembly is hampered due to the misfolding of nascent rRNA. However, RNA misfolding in general was shown to be resolved by RNA chaperones such as DEAD-box proteins. Using single molecule fluorescence microscopy, I show that the E. coli DEAD-box protein CsdA (DeaD) strongly accelerates ribosomal protein uS4 binding by facilitating proper folding of the nascent rRNA. Unstable RNA structures are unfolded by CsdA, whereas stable RNA structures resist unwinding. Consequently, CsdA unfolding becomes less frequent as more ribosomal proteins add to the complex. The results demonstrate that disassembly of unstable, nascent RNA-protein complexes by chaperones fuels the search for native structure. I propose that general chaperones create a gradient of disassembly that steepens the hierarchy of proper protein addition until late assembly intermediates escape unwinding and commit to 30S maturation.
Eukaryotic ribosome assembly requires many DEAD-box chaperones, yet it is also affected by the liquid-liquid phase-separated environment in nucleoli. It is thought that the dense environment of the nucleolus is beneficial for ribosome assembly because it chaperones rRNA folding and spatially sorts ribosome assembly factors. I developed a smTIRF assay to monitor the docking of the Tetrahymena ribozyme P1 helix in fibrillarin/Nop1 droplets. Nop1 is the yeast homolog of fibrillarin, which is a major constituent of the dense fibrillar component (DFC) in the nucleolus, the site of early steps of ribosomal assembly. I found that Nop1 destabilizes the docked conformation of the ribozyme equally well in both dilute and condensed phases, without any appreciable difference. My results show that RNA folding is affected by the microscopic and non-specific interactions between Nop1 and RNA but not the dense environment inside fibrillarin/Nop1 droplets. Nop1 binding also inhibits rRNA unwinding by CsdA, suggesting that intricate competitions between rRNA-binding proteins occur in the nucleolus. Conversely, transient, non-specific interactions between the rRNA and Nop1 can be replaced by specific interactions with ribosomal proteins. The gradual loss of non-specific nucleolar protein binding during ribosome maturation may help drive the exit of assembled pre-ribosomal particles from the nucleolus and into the nucleoplasm. Altogether, this work shows how rRNA interactions, non-specific interactions with nucleolar proteins, unwinding by RNA helicases, and specific assembly with ribosome proteins all contribute to the landscape for ribosome assembly
Link Homologies, Bott-Samelson Spaces and Twisted Cohomology
Get PDFThis thesis studies categorified invariants of links, that is, embeddings of one or more circles into three-dimensional space. Such invariants take the form of link homologies, which associate chain complexes to links so that their homology groups provide richer information than the polynomial invariants they categorify. Among them, we have HOMFLY-PT link homology and sl(n)-link homology, which are categorifications of the corresponding HOMFLY-PT and sl(n)-link polynomials.
Our work explains and builds upon Khovanov's formulation of HOMFLY-PT homology in terms of the Hochschild homology of Soergel bimodules, aiming to incorporate integral sl(n)-link homology into that framework. This is done through an algebro-topological approach, applying Borel equivariant cohomology to Bott-Samelson spaces--topological counterparts of Soergel bimodules.
This perspective illuminates interesting relationships between link homologies. Specifically, we demonstrate how an integral version of the Rasmussen spectral sequence, which relates HOMFLY-PT and sl(n)-homologies, can be expressed entirely in terms of the Hochschild homology of Soergel bimodules.
Furthermore, we compare different flavors of sl(n)-link homology with the link invariants constructed by Kitchloo through twisted Borel equivariant cohomology. In particular, we show that these geometric constructions based on Bott-Samelson varieties yield not only integral sl(n)-link homology but also a `universal equivariant' sl(n)-link homology, from which all other flavors can be derived