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Closing in Action: Towards a Polarisation Around the Future and Memory of Catholicism in Québec? Ethnography and Media Analysis of Three Notable Church Closures at the Beginning of the 21st Century
No full textThis thesis analyses three conflictual Catholic church closures in Québec (2013-2015) - in Rimouski (Saint-Germain-de-Rimouski), Québec City (Saint-Jean-Baptiste-de-Québec), and near by Drummondville (Saint-Edmond-de-Grantham) - selected from more than 600 cases to capture urban, regional, and rural contexts, using immersive ethnography to understand actors' competing logics. It examines secularization in the 21st century, highlighting a shift from lived religion to religious memory, and explores how religion and heritage intertwine as churches close. The study emphasizes how communities negotiate closures rather than why, showing that each case mobilizes religious, civic, and political forces. Ultimately, it argues that Québec is undergoing a profound sociocultural transformation marked by both accelerated secularization and an intensifying polarization around the future and memory of Catholicism. --
Cette thèse analyse trois fermetures conflictuelles d'églises catholiques au Québec (2013-2015) - à Rimouski (Saint-Germain-de-Rimouski), à Québec (Saint-Jean-Baptiste-de-Québec) et près de Drummondville (Saint-Edmond-de-Grantham) - sélectionnées parmi plus de 600 cas, afin de refléter les contextes urbains, régionaux et ruraux, et ce, en utilisant l'ethnographie immersive pour comprendre les logiques concurrentes des acteurs. Elle examine la sécularisation au XXIe siècle, en soulignant le passage de la religion vécue à la mémoire religieuse, et explore la manière dont la religion et le patrimoine s'entremêlent à mesure que les églises ferment. L'étude met l'accent sur la manière dont les communautés négocient les fermetures plutôt que sur les raisons qui les motivent, montrant que chaque cas mobilise des forces religieuses, civiques et politiques. En fin de compte, l'auteur soutient que le Québec connaît une profonde transformation socioculturelle marquée à la fois par une sécularisation accélérée et une polarisation croissante autour de l'avenir et de la mémoire du catholicisme
Language-Guided 4D Object Reconstruction from Videos
No full textCreating 4D assets from real-world data is a crucial problem in computer vision, with applications in Augmented Reality (AR), Virtual Reality (VR), and animation. However, this task is often cost-prohibitive, as it requires both detailed object 3D structure and accurate motion within a complex 3D environment. This thesis proposes a framework that converts object-centric monocular videos into 4D representations. The two primary challenges we aim to tackle are: 1) key object extraction from the video, and 2) dynamic object capture and representation.
For the first challenge, Referring Video Object Segmentation (RVOS) is employed, using language prompts to identify target objects while ignoring distracting backgrounds. The limitations of existing RVOS methods are first analyzed, particularly in terms of temporal consistency, and then enhanced by improving the understanding of temporal context. Additionally, we adapted previous frameworks into online methods capable of processing video frames in real-time, which significantly increases the usability.
For the second task, 3D Gaussian Splatting (3DGS), a popular method for 3D scene representation, serves as the baseline for dynamic object representation. One main limitation in 3DGS is identified, that large object motions cannot be well handled during reconstruction. To address this, a motion-deformation-decoupled dynamic 3DGS structure is designed to estimate the object's large overall motion and the local deformation separately, which can represent highly dynamic objects better. Additionally, monocular casual video has an inherent limitation on spatial-temporal observations. Only a limited part of the object can be observed at each point in time. This leads to undesired artifacts in weakly observed areas. To overcome this limitation, a novel framework is proposed to leverage the prior of the 2D generative model to import additional constraints over the weakly observed spatial-temporal areas.
In summary, this thesis takes a casually captured monocular casual video, along with a descriptive sentence pointing to the desired object as input and produces a complete 4D object with accurate 3D structure and corresponding motion, which advances the usability of 4D reconstruction in practical applications
Chemsex Among HIV Positive Gay, Bisexual, and Men Who Have Sex with Men: Exploring the Intersections Between Sero-status, Mental Health, Substance Use, and Addiction.
No full textThe use of amphetamines and other dissociative substances to facilitate sexual contact is part of a growing phenomenon among some groups of gay, bisexual, and other men who have sex with men (GBMSM) – particularly, those living with HIV. Colloquially known as “chemsex”, this practice is commonly discussed in extant literature in terms of its purported risks; less however, is known about the rewards this practice holds for those who participate and the motivations for engagement among HIV positive GBMSM as a unique subculture. To address gaps in nursing knowledge related to chemsex engagement among GBMSM living with HIV, critical qualitative research was undertaken. The objectives of this study were to (1) identify the dynamics, values, behaviours, and beliefs of HIV positive GBMSM engaging in chemsex; and (2) examine the effect of chemsex on the healthcare needs and risk-taking behaviours to improve overall health outcomes for this group. This research employed a critical ethnographic methodological approach using interviews as the main form of observation. Findings revealed that motivations for chemsex initiation were primarily fueled by a desire for change – particularly with respect to HIV subjectivity and mental health challenges. Within the world of chemsex, these men had the opportunity to become alternate versions of themselves and to live and participate freely and without restrictions. Chemsex subcultures were, however, also marked by a distinct set of norms (rules, values, behaviours) that marked participation. Depending on their position in a given moment in time, these norms would vary between pleasure, subjectivity, and tension. Despite the variability in their experiences, chemsex subcultures ultimately provided a sense of community to these participants. These were spaces in which they felt accepted, loved, cherished – and would go to any length to maintain the health and wellbeing of their peers. These findings suggest a depth to chemsex engagement among HIV positive GBMSM that should be met in nursing practice with flexibility. That is, future initiatives must be shaped by patient needs (and not what nurses think they require) and must acknowledge the variability in experiences of this subculture
Victime, survivante, battante : comment crient-elles leur colère ? Se (re)construire après une agression sexuelle : l'expérience de jeunes femmes françaises, positionnements identitaires et stratégies de coping
No full textLe 2 novembre 2020, une vie bascule, celle de Gisèle Pelicot. Mais chaque jour dans le monde, c'est aussi celle d'un nombre incalculable de femmes qui virent au cauchemar : les violences sexuelles peuplent le quotidien d'une société gouvernée par un patriarcat tyrannique et sexiste. Cet écrit se penche sur le viol et l'agression sexuelle comme faits de société, et s'interroge sur le statut de celles qui l'ont vécu, constatant ainsi comment patriarcat et culture du viol collaborent pour perpétrer une légitimité des hommes - et de certaines femmes - à exercer un contrôle sur le corps, et par extension l'identité des femmes. Le témoignage apparaît alors comme un outil clé pour se défaire des injonctions sociales : victime aux yeux de la société, mais pas toujours, et pas seulement. Néanmoins, les tentatives de reprise de pouvoir sur sa propre identité sont constamment freinées par une autre sorte d'injonction : de la « bonne » victime à la « mauvaise » survivante et, envers et contre tous, toujours « battante »
High-Resolution Numerical and Experimental Study of Dense Jets
No full textThe rapid global expansion of seawater desalination has emerged as a critical solution to freshwater scarcity, yet it generates large volumes of saline and thermal effluents that pose challenges for coastal and marine environments. The near field hydrodynamics and mixing of desalination discharges are governed by the delicate interplay between jet momentum, buoyancy, and ambient conditions. An accurate prediction of these processes is vital for designing outfalls that ensure regulatory compliance and minimize ecological impacts. Despite significant progress in experimental and numerical modeling, notable knowledge gaps remain in (i) the specification of realistic boundary conditions for high-fidelity simulations, (ii) the representation of jet behavior in complex stratified and crossflow environments, and (iii) the integration of experimental and numerical data within predictive, computationally efficient modeling frameworks. This thesis addresses these challenges through a coordinated program of advanced experiments, high-resolution simulations, and multi-fidelity statistical modeling.
The first part of the thesis investigates the role of inlet boundary conditions in Large Eddy Simulation (LES) of negatively buoyant jets relevant to desalination outfalls. Multiple inflow turbulence treatments, including mapped, synthetic, and stochastic methods, were systematically compared against high-resolution Particle Image Velocimetry (PIV) measurements. The study demonstrated that mapped inflow and synthetic turbulence approaches are most effective in reproducing near-field turbulence generation, velocity statistics, and dilution performance, while oversimplified uniform inflows led to systematic underprediction of mixing. This highlights the decisive role of physically consistent boundary specification for LES reliability.
The second part examines dense jets in crossflow and stably stratified environments using LES. A suite of simulations covering a wide parameter space of densimetric Froude numbers, velocity ratios, and stratification strengths was conducted. Results revealed that ambient stratification strongly suppresses vertical penetration and enhances asymmetric entrainment, while crossflow drives trajectory deflection and modifies coherent turbulent structures. These findings extend the current understanding of jet–ambient interactions and provide physically grounded benchmarks for the design of desalination outfalls in variable environments.
The third component of the thesis develops a Bayesian hierarchical multi-fidelity framework that combines low-fidelity Reynolds Averaged Navier-Stokes (RANS), high-fidelity LES, and experimental Particle Image Velocimetry (PIV) and Laser Induced Fluorescence (LIF) data within a Gaussian Process Regression (GPR) model. This approach exploits the complementary strengths of different fidelities, achieving robust predictions of terminal rise height, return point dilution, and centerline concentration while substantially reducing computational cost. The framework demonstrates the feasibility of integrating simulation and measurement data into unified, uncertainty-aware predictive models for environmental engineering applications.
Finally, Direct Numerical Simulation (DNS) of a positively buoyant thermal jet is presented as a benchmark. The DNS resolves turbulence and scalar transport at all relevant scales, producing high-fidelity datasets of mean flow, turbulence statistics, and entrainment. These results elucidate fundamental turbulence–buoyancy interactions and serve both as validation for LES subgrid-scale models and as calibration input for the multi-fidelity framework.
The thesis makes four main contributions: (1) it establishes best practices for LES inlet boundary conditions in desalination jet simulations; (2) it quantifies the interplay between crossflow, stratification, and dense jet dynamics; (3) it introduces and validates a Bayesian multi-fidelity modeling framework for efficient prediction of discharge behavior; and (4) it generates high-resolution DNS datasets of thermal jets that advance physical understanding and provide a benchmark for future model development. Collectively, these contributions enhance predictive capabilities for desalination discharges, offering methodological and physical insights that support the design of environmentally sustainable outfalls
How prevalent is osteoporosis in a high-risk subgroup? A multicenter study of postmenopausal women hospitalized for fractures in China
No full textAbstract Introduction Osteoporosis is the principal underlying cause of fractures in postmenopausal women. Despite consensus on the importance of secondary prevention, a profound treatment gap exists, partly due to the lack of precise data on disease burden in the highest-risk population. This study aimed to determine the prevalence of osteoporosis and its associated factors specifically among postmenopausal women hospitalized for fractures, a critical evidence gap in orthopedic practice. Methods We conducted a multicenter cross-sectional study across eight tertiary hospitals in China between March and May 2024. Eligible participants were postmenopausal women hospitalized for fractures who met predefined inclusion and exclusion criteria. All participating surgeons completed standardized protocol training for data collection, and each study site contributed up to 160 cases. Results The study included 822 postmenopausal women (mean age: 68.9 ± 10.7 years), with an overall osteoporosis prevalence of 76.9% (95% CI: 73.8%–79.7%). The prevalence was significantly higher among those with longer menopause duration (per year: adjusted odds ratio [aOR] = 1.08, 95% CI: 1.04-1.13, P < 0.001), vertebral fractures (vs patellar, tibiofibular, or ankle fractures: aOR = 3.16, 95% CI: 1.84-5.45, P < 0.001), and a history of fractures (aOR = 8.53, 95% CI: 2.56-52.94, P < 0.001). Conclusions This study reveals an alarmingly high prevalence (76.9%) of osteoporosis among postmenopausal women hospitalized for fractures in China, identifying prolonged menopause, vertebral fractures, and recent fracture history as key risk profiles. The findings mandate a shift in inpatient fracture care. They provide compelling evidence for implementing universal bone health assessment, specifically through in-hospital systems like Fracture Liaison Services (FLS), as a standard of care for this high-risk population to mitigate subsequent fracture risk.Summary For orthopedic surgeons managing fracture care, this study delivers a pivotal finding: osteoporosis is the underlying condition in over three-quarters (76.9%) of postmenopausal women hospitalized for fractures. The prevalence escalates to over 88% in patients with vertebral fractures or a recent fracture history. This quantifies the immense missed opportunity for secondary fracture prevention at the point of care. The data provide irrefutable evidence for implementing in-hospital systems like Fracture Liaison Services (FLS) and routine DXA screening, moving beyond fracture repair to definitive management of the root cause during the critical inpatient episode
Homeostasis of Reactive Oxygen Species in Brain of Hypoxia-Tolerant Naked Mole-Rats
No full textOxygen is essential for aerobic metabolism and for the concomitant generation of reactive oxygen species (ROS) as a by-product. ROS are important cellular signaling molecules, but sudden changes in oxygen availability may disrupt ROS homeostasis, which can subsequently induce oxidative damage and promote cellular dysfunction and death. Despite this, many animals have adapted to life in hypoxic conditions, in part by developing strategies to maintain ROS homeostasis and avoid accumulation of oxidative damage. Of particular interest are hypoxia-tolerant naked mole-rats (Heterocephalus glaber), which are thought to putatively experience recurrent hypoxia/reoxygenation cycles in their burrows. This thesis investigates mechanisms that contribute to ROS balance in naked mole-rat brain cells, and elucidates novel and beneficial adaptations for life in intermittent hypoxia. In chapter 2, I used fluorescent microscopy to determine that, unlike in mice, ROS homeostasis is maintained in naked mole-rat cortical cells exposed to hypoxia (~1% O₂, ~7.4 mm Hg), oxygen glucose deprivation, exogenous ROS application, and respective reperfusions. Then, in chapter 3, I used pharmacological tools to inhibit known sources of endogenous ROS generation. Unfortunately, relative contributions of key ROS generators remain inconclusive, but I found evidence which suggests that XOR may play a major role in ROS scavenging. Finally, I used a high-throughput plate assay to compare ROS scavenging and found that naked mole-rat permeabilized forebrain homogenates have an enhanced ROS scavenging capacity relative to mice, largely due to improved glutathione-dependent scavenging (Chapter 4). Taken together, these findings provide support for my hypothesis that naked mole-rat brain is better adapted for life in intermittent hypoxic conditions, such that naked mole-rat brain cells are better able to prevent oxidative damage during hypoxia and reoxygenation compared to similar cells in hypoxia-intolerant mice
Lessons learned from Canadian family physicians deprescribing medications in older adults – a five-year retrospective review of medico-legal cases
No full textAbstract Background Medication-related safety incidents are more common in older adults than in younger populations. Medication review and optimization, including deprescribing, are essential components of strategies to reduce medication-related harm. Deprescribing aims to minimize therapeutic burden by reducing medications that no longer provide net clinical benefit or by substituting safer alternatives. Herein we sought to use a national pan-Canadian repository of medico-legal cases to identify opportunities for improving deprescribing practices in primary care for older adults. Methods We conducted a five-year retrospective review (2018–2022) of closed Canadian medico-legal cases relating to deprescribing involving family medicine physicians and patients age 65 or older. We analysed cases related to deprescribing and created composite case examples to illustrate both areas for improvement and examples of appropriate care despite the receipt of a complaint or civil legal action (collectively, medico-legal cases). Results We identified 31 medico-legal cases, of which 29 had undergone expert review. Experts identified areas of improvement related to deprescribing including conducting assessments to determine appropriateness of deprescribing, using a multidisciplinary approach to create a safe tapering plan that includes monitoring and follow-up, establishing clear communication with patients and their authorized substitute decision-makers, and documenting clearly and appropriately. Although experts often explicitly identified these elements as present, they were critical of the deprescribing-related care in half of cases. Conclusions Medico-legal cases highlight several key areas for improving deprescribing in primary care, particularly around comprehensive patient assessment to inform deprescribing decision-making and clear communication of treatment plans with relevant decision-makers. The cases also demonstrate that the process of deprescribing and the patient-physician relationship is complex and that complaints can occur even when physicians are safely deprescribing
Protocol for a review of statistical methods used to estimate risk ratios and risk differences in parallel cluster randomised trials
No full textAbstract Background Cluster randomised trials randomise groups of individuals, such as clinics, schools, or communities, and are used when interventions apply at the group level, when individual-level interventions risk contamination between participants, or to reflect real-world implementation. When outcomes are binary, treatment effects may be expressed as relative measures (such as odds ratios or risk ratios) or absolute measures (such as risk differences). CONSORT guidelines recommend reporting both, but risk ratios and risk differences are often underreported compared to odds ratios. Estimating these measures in cluster trials is more complex than in individually randomised trials, requiring appropriate handling of clustering, convergence issues, and small sample corrections. There is currently little empirical evidence describing which statistical methods are used to estimate these effect measures in published cluster trials. Methods This protocol describes the planned methods for a methodological review of published cluster randomised trials. We will use an existing database of 800 trials conducted in low- and middle-income countries. From this, we will identify a subset of trials with a parallel design and a binary primary outcome. Trials reporting a risk ratio or risk difference for the primary outcome will undergo further detailed data extraction. We will summarise the methods used to estimate these effects, including how clustering and small sample sizes were handled, and whether estimates were adjusted for covariates. Discussion This review will provide the first detailed description of how risk ratios and risk differences are currently estimated and reported in cluster randomised trials. The findings will inform the development of methodological guidance and help identify gaps in reporting and implementation. This is particularly important as interest grows in improving estimand specification and the clarity of statistical analysis plans
Applications of Network Theory to North America Stock Markets
No full textThis dissertation applies network theory to investigate the structure, direction, and dynamics of systemic risk in North American equity markets, focusing on the Toronto Stock Exchange (TSX 60) and Nasdaq 100. The research combines three complementary analyses to provide a deep understanding of market connectedness across pre-COVID, pandemic, and post-pandemic periods. First, partial correlation and mutual information concepts are employed to identify edges in order to construct an undirected network for each stock market, namely the TSX 60 and the Nasdaq 100. We use several network analysis techniques, such as graphical LASSO (GLASSO), latent variable time-varying graphical lasso (LTGL), and minimum spanning tree (MST), to reveal key patterns of interconnectedness and shifts in the stock market across distinct sample periods: the “pre-COVID-19”, “COVID-19”, and “post-COVID-19” periods. Findings reveal shifts in sectoral centrality and the emergence of systemically important nodes during periods of market stress. Second, the study transitions to directed network analysis, applying a range of methodologies, including net transfer entropy, the Diebold-Yilmaz (DY) spillover index and empirical mode decomposition, to identify edges and construct a directed volatility-spillover network. The findings reveal the distinctive structures of the two stock markets in both short-term and long-term frequency data. Both the TSX 60 and Nasdaq 100 networks demonstrate a robust interconnectedness and high volatility transmission during the pandemic, reflecting heightened market uncertainty. Furthermore, the study compares the net transfer entropy and the DY spillover index and finds that the DY spillover index is also capable of identifying the volatility spillover in a smoothed pattern from a long-term frequency data. Finally, a novel integration of the directed network framework with a Susceptible -
Infected - Recovered (SIR) epidemic model is used to simulate the dynamic propagation of financial contagion. By calibrating transmission (β) and recovery (γ) rates from empirical data, the model shows how network topology and sectoral positioning influence contagion speed and scale. The dissertation advances the literature on financial networks, systemic risk, and contagion modeling by uniting static structure, directional influence, and dynamic simulation within a single framework. The results provide actionable insights for policymakers, regulators, and investors aiming to identify vulnerabilities, design targeted interventions, and
strengthen market resilience against future shocks