VictorJuiz/thesis huggingface dataset:
Time-resolved Electron and Serial X-Ray Crystallography of PbS Quantum Dots and Biomolecules

This thesis reports on the results of a series of crystallographic studies performed using ultrafast electron diffraction (UED) and serial X-ray crystallography on semiconductor nanocrystal and protein samples. In the first part of the thesis, ultrabright femtosecond electron pulses generated using a radio frequency-compressed photocathode electron source are employed to measure the photoinduced lattice response of lead sulfide (PbS) colloidal quantum dots following the optical generation of above-bandgap excitons. Short-range nonthermal lattice distortions are observed on the picosecond timescale in the form of exaggerated atomic disorder in the (100) crystallographic directions and deviations from a purely thermal response at short distance scales (< 12 Å). These structural changes are found to be related to surface charge trapping through size- and surface-series experiments and a pair distribution function analysis. In the second part of the thesis, a description of a new experimental scheme for serial X-ray crystallography is presented. The recent advent of free-electron lasers (XFEL) in the hard X-ray wavelength range (< 1 Å) has necessitated the use of serial femtosecond crystallography (SFX) for static and time-resolved structure determination. This has driven the innovation of novel sample delivery techniques to meet the stringent demands imposed by the SFX approach. This thesis outlines the development and implementation of a versatile high-speed fixed-target sample delivery technique based on a microfabricated silicon chip and spectroscopic sample mapping capability for use at both XFEL and synchrotron light sources. Application of the “serial crystallography chip” method maximizes hit-rates and minimizes sample consumption, as demonstrated by crystallographic experiments on the proteins: carboxy-myoglobin, lysozyme and fluoroacetate dehalogenase. An extension of the method which combines fixed-target serial crystallography with conventional rotation crystallography is also presented, which allows for X-ray induced damage-free structures to be obtained using serial crystallography at synchrotron light sources.

Keywords: Electron-Phonon Interactions
Fixed-Target Serial Femtosecond Crystallography
Semiconductor Quantum Dots
Ultrafast Electron Diffraction
Advisor: Miller, R. J. Dwayne
Advanced Boundary Element Techniques for Multiregion and Multiscale Electromagnetic Modelling

The rapidly increasing complexity of electronic hardware, such as integrated circuits and advanced electromagnetic surfaces, tends quickly to outgrow the capabilities of existing electromagnetic simulation tools. For example, complex chip- and package-level interconnect networks require broadband full-wave simulations that capture electromagnetic fields both inside and outside each object in the structure, including skin effect in conductors. The boundary element method has emerged as an appealing modelling technique because it allows solving three-dimensional problems using a two-dimensional surface mesh. However, existing boundary element formulations are limited in their robustness, efficiency, and scalability for modelling systems which are multiscale (i.e., extreme variations in size, frequency, and possibly material properties) and multiregion (i.e., structures involving penetrable objects). In particular, key challenges include a limited ability to handle large structures, a poor trade-off between robustness and efficiency, and numerical instability at low frequencies. In this thesis, new surface integral formulations are developed to meet these challenges in a scalable, rigorous, and accurate manner. The new frontier of potential-based integral equations is explored to develop a multiregion boundary element formulation capable of modelling interconnects accurately over an unprecedented frequency range. Realistic numerical examples drawn from various applications demonstrate progress towards alleviating some of the core challenges in multiscale and multiregion electromagnetic modelling.

Keywords: Boundary element method
Computational electromagnetics
Computational science
High-performance computing
Integral equations
Numerical methods
Advisor: Triverio, Piero
The Sword of the Immanent God: Heinrich Heine’s Sensualist Style

In classified communications surrounding the notorious ban on the junges Deutschland, the officials responsible single out Heinrich Heine’s essay Zur Geschichte der Religion und Philosophie in Deutschland, claiming that it threatens the existing order partly because of the sensualist sociopolitical programme it promotes, which aims at a “Rehabilitiren der Materie” and its “Versöhnung mit dem Geiste,” but primarily because of the text’s style—which, the authorities suggest, somehow reflects its sensualist aims. Following up on this observation and corroborating indications from Heine himself and his readers, the present study explores the hitherto largely unexamined link between sensualism and style in the Essay.In doing so, the study focuses on a practical contribution the Essay is designed to make to its sensualist goals—goals which consist of suppressing two conceptions of God that oppose sensualism (spiritualism and deism), promoting a different notion of the divine that supports the sensualist programme (pantheism), and subsequently executing a sensualist revolution. The analysis of the practical contribution the Essay makes to its goals begins by extracting Heine’s general conception of that contribution, according to which it consists of the use of a material language to embody ideas so that they can move matter—a way of writing which reflects the sensualist aim to reconcile spirit and matter and is therefore termed the sensualist style. I then discuss each element of the sensualist style in detail, formulating a theory and then showing how that theory is reflected in the Essay’s own style: I argue that material language refers to a plastische way of writing consisting primarily of Figuren, the vivid representation of the sensory aspect of human beings; embodiment of thought, to the use of Figuren that constitute visible thoughts, sensory, bodily-material manifestations of ideas; and movement of matter, to the power such embodied ideas possess to affect the reader’s bodily behaviour, either drawing them towards or pushing them away from the embodied thought—which, in the Essay, is used to repel readers from a spiritualist or deist way of life and turn them into an avatar of pantheism.

Keywords: Embodiment
Heinrich Heine
Movement
Pantheism
Sensualism
Style
Advisor: Goetschel, Willi
Policing “Target People”: Crime Control and Political Repression in the People's Republic of China

How are political repression and crime control related in authoritarian states? And why do authoritarian states adapt their control apparatus? To answer these questions, this dissertation focuses on policing in the People’s Republic of China under the Hu Jintao (2002-2012) and Xi Jinping (2012-2022) administrations. Across both administrations, victims of political repression included dissidents, ethnic minorities, and petitioners. Yet, these were not the only targets of state control. China's police also surveilled, harassed, and detained former prisoners, users of drugs, and those with mental illnesses. Instead of dividing targets of political repression from targets of crime control, China’s police categorized a vast array citizens under a common label: “target people.” This dissertation is comprised of four thematically-linked chapters addressing two conceptual questions: how are political repression and crime control related in authoritarian states like China? And why do authoritarian states adapt their control apparatuses? In answering these two questions, this dissertation argues that state repression under the Hu and Xi administrations was defined by three broad trends: the conflation of crime control and political repression; police collaboration with other party-state organs to deepen control in the community; and the growing use of control mechanisms against the general public. By exploring these policing practices, this dissertation contributes to the literature on how authoritarian states govern and how their repressive apparatuses adapt.

Keywords: Authoritarian politics
Chinese politics
Drug policy
Policing
Political repression
Surveillance
Advisor: Fu, Diana
Development of a Prototype High-power Ultrasound Phased-array System for the Treatment of Deep Vein Thrombosis

Deep Vein Thrombosis (DVT) is the formation of thrombus in the deep veins of the body. The most important sequela of DVT, pulmonary embolism, is a major cause of mortality and morbidity due to the occlusion of the blood vessels in the lung. Common clinical treatments can provoke considerable consequences such as bleeding and damage to the vessel wall. It is well established that high-power ultrasound as a potentially non-invasive method can mechanically fragment the thrombus and restore the blood flow in the absence of lytic agents. Using single-element, focused transducers in most of these studies can lead to limitations such as lack of steerability and control of the focus. There is, therefore, a need for the development of high-power 2D phased-array transducers with the ability to electronically steer the beam with substantially shorter time delays to cover the whole target volume before the clot is released. This thesis presents the development of a novel high-pressure amplitude clinical transmit and receive array system for the treatment of DVT. We addressed the challenges associated with 2D fully steerable arrays such as high electrical impedance and element breakdown at high voltages, and then constructed a 64-element (8 × 8) high-power phased-array module operating at 260 kHz. The module elements generated 1.01±0.09 MPa at 2 mm distance while maintaining this pressure level over 10,000 sonication repetitions. Then, we modeled and constructed a 16-module cylindrical array system. The challenges associated with the large focal size of the low frequency ultrasound were surmounted with the design and a FWHM focal size (3.7 × 4.1 × 11.2 mm), and a pressure amplitude (34 MPa) suitable for DVT thrombolysis was achieved. In vitro experiments manifested a partial and complete clot breakdown at 11.5 and 15 MPa pressure at the focus. To complete the array system and qualify it for the clinical applications, we incorporated a receiver array (516 kHz) into the system. Modeling and testing of the receiver array demonstrated acceptable passive acoustic maps at different steering locations. Overall, the developed transmit-receive array system exhibited strong potential to be used in future in vivo and clinical treatments.

Keywords: High Intensity Focused Ultrasound
Sonothrombolysis
Ultrasound Transducers
Advisor: Hynynen, Kullervo
South Asian Women Together in a Health Initiative (SATHI): A Pilot Randomized Controlled Trial

Background. Canadian South Asian women have high rates of cardiovascular disease and low rates of physical activity. The primary objective of this study was to assess feasibility (recruitment, retention, engagement, acceptability) of the South Asian women Together in a Health Initiative (SATHI) using the Medical Research Council’s guidance framework. The secondary objectives were to determine potential effects of SATHI on physical activity, anthropometric risk, and self efficacy. Exploratory analysis of the relationship of self-efficacy and step count was also undertaken. Methods. SATHI was a 12-week pilot randomized controlled trial of South Asian women, ages 24-39, in the Greater Toronto Area, with no previous medical history. The control group received a pedometer, the Canadian 24-Hour Movement Guidelines for Adults 18-64, and a physical activity logbook. The intervention group received a pedometer, a physical activity logbook, and the SATHI intervention consisting of a culturally tailored physical activity education with peer support program based on Bandura’s theory of self-efficacy. Physical activity and anthropometric data were collected pre- and post-intervention. Data were analyzed using descriptive statistics and linear mixed models for repeated measures. Results. Of the 467 South Asian women screened, 67.7% (n=316) were deemed eligible but only 15.2% consented to participate in the study. No participants were lost to follow up. All predefined engagement criteria were met (reading/watching education materials, peer interactions, submitting step counts, documenting physical activity). However, fewer participants completed the recommended physical activity for South Asians than anticipated. Acceptability of the SATHI intervention was 100%. Compared to the control group, the intervention group had significantly increased their self efficacy (SE, 106.9; 95% CI, 62.6-487.5) and step count (SE, 1151.7; 95% CI, 760.1-5340.0). However, there were no significant between group differences in anthropometric measures. Self-efficacy was also positively related to step count, r(46)=0.56, p<0.001, indicating a large effect size. Conclusions. It is feasible to conduct the SATHI trial in a South Asian community. It has the potential to improve physical activity among this at-risk population. A larger trial should be undertaken to further investigate the effectiveness of SATHI on anthropometric and cardiovascular disease risk reduction. The trial was registered at clinicaltrials.gov (NCT03667976).

Keywords: Cardiovascular Disease
Peer Support
Physical Activity
Self Efficacy
South Asian
Women
Advisor: Parry, Monica
Filling the Gaps: How Attentional States Influence Memory Formation in Children and Adults

To understand the complex world around them, children critically depend on the ability to form memories. But in many moments, children struggle to form memories and often remember qualitatively different (and less goal-relevant) information than adults. Although these findings could reflect immature memory processes, another possibility is that worse memory in childhood reflects the slow development of attention. In adults, successful memory depends on the ability to endogenously sustain and selectively attend to task relevant content–abilities that are immature in childhood. In this dissertation I report 4 experiments that explore the relationship between attention and memory formation in children and adults. In Chapter 2, I describe a study examining how endogenous fluctuations in attention influence the ability to form memories in each moment. I find that endogenous fluctuations in attention closely correlate with the ability to form memories in children and adults, but covary with memory formation more closely in children. In Chapter 3, I turn to exploring how reactive shifts in attention, elicited by errors, shape memory formation in adults. I find that making an error increases arousal and captures attention leading to immediate memory decrements. Finally, in Chapter 4, I ask why children tend to be more likely to remember goal-irrelevant information than adults. I find that children have reduced memory for target information but enhanced memory for goal-irrelevant information relative to adults. Moreover, lower memory selectivity is closely related to poorer performance on an attentionally demanding task which mediates age-differences in memory selectivity. Overall, I argue that these data illustrate that the slow development of attention (rather than memory per se) may in large part explain age differences in memory performance after middle childhood.

Advisor: Finn, Amy S
Duncan, Katherine
Where Sickness Comes From: Reading and Unsettling Medicine in the Canadian Arctic

My research project examines the written accounts of eight physicians who document their practice of medicine in the Canadian Arctic: Lorris Elijah Borden (1903–1904), Leslie David Livingstone (1922–1925), Jon A. Bildfell (1940–1942), Joseph P. Moody (1946–1949), Charlie O’Connell (1955), Otto Schaefer (1953–1985), John H. Burgess (1973–2003), and Kevin Patterson (1999, 2006). Through their life-writing practices, they enact both competency and anxiety, which are ultimately the tensions of the settler-colonial context. Discursive, affective, and visual-spatial readings of these accounts reveal how the framing of disease in the settler-colonial context engendered physician identity and rationalized the forms of healthcare established for Inuit. A discourse analysis of these accounts reveals how the clinical formulations and diagnoses advanced by these physicians transformed the Inuit patient into an uncivilized and uneducated figure, part of a dying culture ill-equipped to participate in managing their own healthcare needs. The Arctic doctor, in contrast, was knowledgeable, competent, and heroic. Affect theory shows how the reading and representation of Inuit affect, and the corollary affect of doctors, supported these discourses. The binaries used to characterize Inuit—grateful or hostile, medically compliant or non-compliant—codify the exchange between doctor and patient. Disruptive physician affects—shame, loneliness, grief—discompose the medical-settler-colonial encounter and betray their uncertainty and vulnerability. The Arctic landscape and frontier space in which the clinic is located is critical to this formation of physician identity. The photographs of landscapes and patients in the clinic bring the masterful gaze that surveys the land and the medical gaze that assesses patients into the accounts. Yet the land—vast and barren, gendered as an unwelcoming and monstrous woman—tests the physicians’ masculinity and medical assurance. Until medicine acknowledges its role in establishing and maintaining settler-colonialism, reconciliation will not be possible. More broadly, physicians can benefit from critical tools for analysis and reflection, including postcolonial and Indigenous critical perspectives. Narratives by Inuit, presented here alongside this physician life-writing, demonstrate what has been largely overlooked by these physicians and not grasped by Western biomedicine. Inuit qaujimajatuqangit is contained in narrative forms by Inuit writers and artists, and offers cultural tools for wellness and resilience.

Keywords: Inuit
Narrative medicine
Nunavut
Postcolonial medicine
Advisor: Kortenaar, Neil ten
Determinants of State Repression in Authoritarian Regimes: Egypt between 2004 and 2013

This dissertation aims to advance scholarly understandings of authoritarian repression by analyzing patterns of state violence against collective action. Despite the importance of violent repression to authoritarian politics, autocratsâ decision calculus for using coercion has been undertheorized. My project addresses this gap by identifying three types of coercive responses, toleration, low-intensity coercion and high-intensity coercion, and argues that a regimeâ s choice of coercive tactic depends on two factors: the levels of threat posed by the protesters and the risk of backlash after repression. These two factors lie at the core of how authoritarian regimes assess the costs and benefits of repression and thus shape when and why they repress. My argument predicts levels of repression based on observable characteristics of the opposition: the level of polarization of opposition forces, the demands that protesters make, and the geographic spread of protests, which I call "diffusion." I test this argument through an in-depth analysis of Egypt that examines the security forces' shifting reactions to popular protests. I focus on two periods that illustrate important variation in state repression against collective action: the late Mubarak presidency (2004-2011) and the period after the military takeover on July 3rd 2013. My evidence includes an original dataset of protest-police responses as well as interviews with activists and political actors. I further demonstrate the generalizability of my claims beyond Egypt through a comparative case study of Indonesia in the 1960s and a large-N study of state repression.

Keywords: Authoritarianism
Egypt
Indonesia
Middle East and North Africa
State Repression
Advisor: Way, Lucan A.
Towards a Values-Based Data Governance Theory in the Social Economy in Ontario

This thesis develops a Values-Based Data Governance (VBDG) theory by understanding the political, cultural, ideological, and historical contexts for governance of data in social economy organizations (SEOs) with a focus on Ontario, and more broadly Canada. The social economy has a different set of values which are more equity and human rights oriented compared to the public and private sectors. The primary issue with the current absence of a data governance theory is that harms to equity-seeking groups, such as breaches of the right to privacy, gender and racial inequities, and exploitation of labour, can be exacerbated by SEOs unreflexively implementing data-intensive technologies. One of the findings of this thesis is that SEOs are adopting technologies without having a coherent theory of data governance. Countering these problematic trends, and changing the trajectory of SEO adoption of technology toward a more preventive rather than reactive process requires a VBDG theory. The main research questions guiding this study are the following: What are the theoretical gaps in understanding data governance for SEOs, from a Canadian and Ontario context? Can the gaps identified be addressed by a new theory of Values-Based Data Governance (VBDG)? A VBDG theory is presented as a solution to values-based dilemmas brought on by unthoughtfully adopting data-intensive technologies, including inheriting private sector and public sector data governance theories (and practices) that exacerbate existing inequities. Deploying a critical theory of technology approach with a theory of data and algorithms as texts inspired by institutional ethnography, the thesis develops a VBDG theory by specifically examining insights generated through grey and academic literature reviews, policy and political economy analysis, and the use of illustrative case studies. The illustrative case studies highlight two significant underserved populations, people with disabilities in Ontario and immigrants to Canada, as examples to illustrate the issues brought on by an absence of or limited data governance strategies in SEOs. The thesis contributes to social economy literature by developing a VBDG theory for SEOs that provides a basis for the adoption of data-intensive technologies that mitigate socio-economic inequities for equity-seeking groups. The developed theory includes the following elements that must be taken into account when implementing a values-based approach to data governance for SEOs: (1) national culture as the primary context for data governance; (2) political economy as an additional context for data governance; (3) organizational culture as an essential component of data governance; (4) organizational incentive systems that mediate the implementation of data governance; and (5) verification and validation as required for ensuring that the principles of data governance are implemented in practice.

Keywords: Civil Society Organizations
Data
Governance
Nonprofit Organizations
Social Economy
Technology
Advisor: Vieta, Marcelo