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Reductive Alkylation Reactions Using Tetramethyldisiloxane and Potassium Tert-Butoxide Via Reductive-Radical Polar Crossover
No full textHypervalent silicon compounds have shown increasing applications and synthetic versatility throughout recent years due to their unique reactivity. In this study, the combination of alkoxide base and silicon hydride species – potassium tert-butoxide (KOtBu) and 1,1,3,3-tetramethyldisiloxane (TMDSO) – facilitates two different reactions involving the formation of C(sp3)-C(sp3) bonds: the hydroalkylation of vinylarenes (chapter 2), and the cross-electrophile coupling of alkyl halides (chapter 3). This simple system of commonly available reagents is suspected to form a hypercoordinate silicon complex capable of acting as a single-electron donor as well as a hydrogen-atom donor. In each chapter, the process of discovery, optimization, scope, and mechanistic investigations are described. In chapter 2, mechanistic studies suggest the dual radical and polar characteristic of the benzyl nucleophile reactive intermediate, proving the system undergoes the process of reductive-radical polar crossover (RRPC) Ultimately, the TMDSO and KOtBu reagent pair is thought to be synthetically useful in performing reactions in transition-metal-, photoredox-, and electrochemistry-free conditions, with a potentially larger number of transformations that have yet to be discovered. The formation of C(sp3)-C(sp3) bonds is fundamental in organic synthesis and continues to be an ongoing field of research. Overall, novel routes towards the hydroalkylation of vinylarenes and cross-electrophile coupling of alkyl halides was successful using commercially cheap and synthetically available starting materials
L'image de l'art : esthétique et politique de la photographie dans les écrits de Jacques Rancière
No full textCette thèse constitue une première étude d’ensemble des écrits de Jacques Rancière sur la photographie, qu’on propose d’analyser à la lumière de l’archéologie du régime esthétique qu’a développée le philosophe dans ses travaux sur l’art et la littérature. On cherche premièrement à dégager d’une lecture croisée des textes du corpus principal une interprétation originale des conditions historico-conceptuelles ayant rendu possible l’identification de la photographie comme médium artistique. En suivant la thèse ranciérienne d’une relation d’inhérence de la politique à l’esthétique, on cherche aussi à extraire de ces textes une « politique de la photographie », dont on tente de montrer qu’elle constitue une alternative valable à d’autres modèles de compréhension de l’efficacité critique des images. Les contributions de Rancière sur ces deux plans sont mises en regard de différentes approches théoriques de la photographie, parmi lesquelles une place privilégiée est accordée à deux paradigmes antagonistes, celui du modernisme, d’une part, et celui du postmodernisme critique, d’autre part. L’une des hypothèses que cette thèse tente de vérifier est que la pensée de la photographie qu’on trouve chez Rancière permet à la fois la critique et le dépassement de chacun de ces paradigmes. À différentes occasions, la thèse met aussi la pensée du philosophe en dialogue avec celle de théoriciens de la photographie qui n’appartiennent ni au courant moderniste classique ni à celui du postmodernisme critique (Roland Barthes, Roger Scruton, Michael Fried, Walter Benn Michaels). On cherche finalement à montrer que les trois régimes de l’art distingués par Rancière peuvent servir à l’élaboration d’une typologie originale des modes de conceptualisation de la photographie dans ses rapports à l’art. Cette traversée des écrits sur la photographie de Rancière permet au final d’établir que ceux-ci forment un corpus plus consistant et plus riche qu’on ne l’a jusqu’à présent reconnu, et que les thèses et analyses qui s’y trouvent formulées méritent l’attention des penseurs actuels de l’art photographique
Inflammatory and Metabolic Mechanisms Activated in Macrophages Exposed to Metal Implant Wear and Corrosion Products
No full textWear and corrosion products from CoCrMo implants have been associated with adverse local tissue reactions that can ultimately lead to implant failure. However, the underlying molecular mechanisms remain largely unknown. Once activated, macrophages (the predominant immune cells in the periprosthetic tissues) secrete pro inflammatory cytokines, including interleukin-1β (IL-1β), which promote and maintain a pro-inflammatory milieu. More specifically, previous results from our group have shown that, among metal ions released from CoCrMo implants (mainly Co²⁺ and Cr³⁺), only Cr³⁺ led to caspase 1 cleavage in bone marrow-derived macrophages (BMDM), suggesting IL-1β release involving the NLRP3 inflammasome. Additionally, Co²⁺ was shown to induce an increase in oxidative stress markers and a metabolic reprogramming away from oxidative phosphorylation (OXPHOS) towards glycolysis in macrophages. However, the specific mechanisms through which CoCrMo implant wear particles (mainly Cr₂O₃ and CoCrMo) and ions (mainly Co²⁺ and Cr³⁺) may induce the activation of the NLRP3 inflammasome and/or potential metabolic alterations contributing to IL-1β synthesis, and thereby to the overall periprosthetic inflammation, remain largely unknown. The first objective of this thesis focused on identifying mechanisms through which Cr₂O₃ particles, CoCrMo particles, Co²⁺, and Cr³⁺ lead to IL-1β release by macrophages. Results showed that IL-1β release induced by Cr₂O₃ particles and Cr³⁺ was both NLRP3 and caspase-1 dependent in BMDM. In contrast, IL-1β release induced by CoCrMo particles and Co²⁺ occurred independently of NLRP3, being caspase 1 independent in response to CoCrMo particles and only partially caspase 1 dependent in response to Co²⁺. Further analysis suggested that the NLRP3 inflammasome activation by Cr₂O₃ particles was cathepsin B dependent and mediated by lysosomal destabilization, whereas activation by Cr³⁺ was mediated by ROS. The NLRP3 independent IL-1β release induced by CoCrMo particles and Co²⁺ was caspase 8 dependent. The second objective of this thesis focused on determining the effects of CoCrMo particles and Co²⁺ on macrophage metabolism. Results showed that Co²⁺ induced a metabolic shift away from OXPHOS towards glycolysis in BMDM. While only Co²⁺ enhanced pentose phosphate ribose-5-phosphate and ribulose-5-phosphate levels, CoCrMo particles bolstered hexoses and pyruvate levels. Moreover, both CoCrMo particles and Co²⁺ induced a non classical alteration of the tricarboxylic acid cycle highlighted by citrate depletion on which the induced IL-1β release was dependent. The third objective of this thesis focused on determining if itaconate and its derivative, 4-octyl itaconate (4-OI), can modulate the metabolic shift induced by Co²⁺ in macrophages. Results showed that both itaconate and 4-OI significantly inhibited Co²⁺ induced IL-1β release by BMDM. Interestingly, only 4 OI decreased both the precursor and mature forms of IL-1β. While neither itaconate nor 4-OI prevented Co²⁺-induced OXPHOS inhibition, both agents prevented glycolytic flux increase. Lastly, only 4-OI moderately increased CD206 expression, suggesting a shift towards an anti inflammatory or reparative phenotype. Overall, the findings of this thesis revealed: 1. the diversity and specificity of the mechanisms by which different wear particles and metal ions from CoCrMo implants can induce IL-1β release in macrophages; 2. the differential effects of CoCrMo particles and Co²⁺ on the metabolic adaptation of macrophages to elicit their pro-inflammatory response; and 3. a promising role for itaconate and its derivative, 4-OI, in mitigating Co²⁺-induced inflammatory response in macrophages, highlighting the therapeutic potential of 4 OI in macrophage metabolic reprogramming to ultimately improve CoCrMo implant longevity
Imagery of Goddesses: Devi-Mahatmya, Hindu Nationalism and Women's Oral Narratives from West Bengal, India
No full textThe research focuses on the imagery of Hindu goddesses in the current socio-political scenario in India under Hindu nationalism. The Hindutva or Hindu nationalist framework believes in a monolithic Hindu identity that supports Brahmanical Hinduism and Brahmanical patriarchal models. Central to Hindutva politics are the bodies of Hindu women and Hindu goddesses. The goddess imagery in Hindutva is drawn from Devi Mahatmya, a 6th-century text dedicated to Hindu goddesses in India (Bacchetta, 1993), which is then refashioned to align with Hindutva's model of Hindu womanhood. Hindutva framework creates a dominant, North Indian, upper-caste, upper-class narrative of the Hindu goddess that erases the plurality in terms of gender, caste, class, ethnicity, and region. The Hindutva narrative also marginalises ordinary Hindu women's understanding of goddesses, which can challenge the homogenous lens of the Hindutva politics. There is a dearth of literature that explores this issue through an intersectional feminist framework that takes into consideration different social categories in the imagination of goddesses. The primary objective of my thesis is to examine goddess representations in Hindutva discourse, Devi Mahatmya, and oral stories of ordinary Hindu women to discover whether/to what extent various types of goddess imagery can reinforce stereotypical and patriarchal gender roles or empower women. The question that guided my analysis is: how do ordinary Hindu women's accounts of goddesses differ from the representation of goddesses in Hindu nationalist politics? My research shows the diversity in goddess imagery, both in the text Devi Mahatmya and in women's oral narratives of goddesses, which presents a counter-narrative to the Hindutva framework of goddesses. The findings point to the empowering, ambiguous, and regional variations in the divine feminine imagination, in contrast to the patriarchal, homogenous, and casteist portrayal of goddesses in Hindutva discourse
Advancing Cyber-Physical Systems Testing with Machine Learning: Effective, Reliable and Interpretable Approaches
No full textCyber-Physical Systems (CPS) are complex integrations of computational and physical processes, deployed in domains such as autonomous driving, aerospace, and networking. Traditional exhaustive testing for CPS is typically infeasible because the space of system states and environmental conditions grows combinatorially. Simulation-based testing offers a more scalable and controlled alternative, but it raises concerns about both effectiveness and reliability. Key issues include the computational cost and inherent flakiness of CPS simulators, along with the difficulty of generating valid and realistic test inputs. Addressing these issues is crucial to ensure that testing not only detects failures but also yields actionable insights for system validation and debugging. This requires interpretable testing outcomes so that engineers can understand the rationale behind test verdicts and use them to guide root-cause analysis, requirements refinement, and design improvements.
This thesis proposes a set of novel, data-driven approaches that integrate search-based software engineering with machine learning to enhance the effectiveness and reliability of CPS testing. First, we develop approaches based on machine learning for test generation. These approaches explore and exploit the search space for identifying diverse system behaviours and exposing failures that lie in boundary regions.
Second, we develop a novel surrogate-assisted test generation technique that reduces dependence on computationally expensive simulators to predict test outcomes while preserving predictive accuracy. Third, we introduce interpretable approaches that provide engineers with clear explanations of the conditions that lead to different system behaviours, such as passing, failing, and non-robust behaviours. Our approaches for explanation are based on interpretable machine learning models and genetic programming. Explanations provided by our approaches are not only accurate but are also interpretable, allowing engineers to easily understand them. Further, our explanations are minimally impacted by the flakiness in the datasets used to infer the explanations, meaning that they remain stable and reliable and thus offer consistent, actionable insight into system behaviour despite underlying non-determinism.
Across case studies in networking, autonomous driving, and industrial-scale Simulink models, our empirical results show that these techniques are accurate and can uncover different system behaviours, such as passing, failing, and non-robust behaviours, while reducing the need for expensive simulator executions. Our results further indicate that the learned artifacts, including failure characterizations, explanations, and automated validators, remain reliable enough to support practical engineering tasks such as triaging flaky outcomes, filtering uninformative tests, and guiding debugging and validation decisions.
Together these contributions enhance CPS testing by improving efficiency, reliability, and interpretability. By systematically generating test cases, drastically reducing computational costs and providing human-understandable explanations for system behaviours, this thesis transforms simulation-based testing from a largely black-box activity into a rigorous, efficient, and insightful engineering process
Setting the Record Straight: Musical Theatre Bootlegs as a Case Study for Counter-Archiving
No full textÀ la demande de l'auteur, le résumé a été retiré en raison de la nature confidentielle de la thèse. Il sera ajouté une fois la période d'embargo terminée.
At the author’s request, the abstract has been removed due to the confidential nature of the thesis. It will be added once the embargo period has passed
Inflammation in Atherosclerotic Cardiovascular Disease: A Heart on Fire
No full textInterest in the role of inflammation in the pathogenesis of atherosclerotic cardiovascular disease (ASCVD) has continued to grow over the past several decades. As the population continues to age, and the burden of ASCVD continues to climb, researchers and clinicians continue to look for novel treatments and targets to reduces the burden and mitigate the effects of ASCVD. In this thesis, the role of inflammation in the pathogenesis of ASCVD was further assessed along with an assessment of potential therapies that could be used to mitigate the effects of inflammation on the cardiovascular system. This thesis comprises six main sections: (1) a systematic review and network meta-analysis looking at the relative efficacy of anti-inflammatory therapies for the treatment of cardiovascular disease; (2) an observational cross-sectional study to evaluate inflammatory biomarkers in patients with acute cardiovascular events and remote cardiovascular events; (3) a protocol for a double-blind randomized controlled trial to evaluate the efficacy of the anti-inflammatory agent, colchicine, in reducing vascular inflammation; (4) a cost-effectiveness analysis of the use of colchicine for ASCVD; (5) a cohort study evaluating the effect of biologic therapy on vascular inflammation in patients with psoriatic-arthritis/dermatologic; and (6) a cohort study looking at the effect of low-dose statin therapy on vascular inflammation in patients with human-immunodeficiency virus (HIV). While inflammation has long been recognized to be an etiological player in the pathogenesis of ASCVD, until recently, studies exploring inflammation as a potential treatment target have been lacking. This has changed in recent years, with an explosion of studies evaluating anti-inflammatory therapies for the treatment of CV disease. The relative efficacy of these therapies remains unknown. Additionally, it remains unknown whether therapies targeting the inflammatory pathway should be used in all patients with ASCVD (or at high-risk of ASCVD) or if we should specifically target high-risk subgroups. Lastly, information with respect to the cost-efficacy of these therapies from a Canadian health-care system perspective remain needed
Spaces and Integration: The Experience of Francophone Immigrants in a Minority Context
No full textFrancophone Minority Communities (FMCs) in Canada face distinct challenges as they increasingly assume the role of immigrant-receiving communities. To sustain their demographic and cultural vitality, FMCs have turned to immigration, making the role of spaces in supporting integration more critical than ever. Drawing on scholarship that highlights the importance of Francophone spaces in fostering linguistic continuity, social inclusion, and intercultural exchange, this study examines how French-speaking immigrants experience and navigate everyday spaces in Ottawa, Canada’s largest and most institutionally dense FMC.
Using a qualitative methodology based on semi-directed interviews and framed by the theory of interculturality and the concept of intercultural spaces, this research examines how physical and symbolic spaces—such as restaurants, schools, places of worship, and cultural centres—serve as entry points for integration. Findings reveal that these spaces often function beyond their formal mandates, offering immigrants a sense of belonging, cultural affirmation, and access to broader social networks. While language was not the primary focus, it emerged as a central theme: Francophone spaces were sought not only for linguistic reasons but also for the emotional security and identity continuity they provided. The study further identifies bilingualism and multilingualism as key markers of openness and diversity within these spaces, reinforcing their potential as sites of intercultural engagement. Ultimately, this research underscores the dual role of spaces and more specifically FMC spaces in preserving linguistic identity and fostering integration, while also revealing the complexities and intersectional barriers that shape immigrant experiences in minority Francophone contexts
The Economics of Charitable Activities in Canada
No full textThis thesis explores how macroeconomic conditions and local community characteristics shape charitable behaviour and the dynamics of charities in Canada. It comprises three chapters that analyse private giving, government funding, and the location decisions of charities. Using the Canada Revenue Agency's Registered Charity Information Returns (Form T3010), macroeconomic indicators, and census data from 1990 to 2021, it combines time-series, panel, and spatial analyses to examine funding flows and organisational behaviour in response to both national economic fluctuations and neighbourhood-level socio-economic variation.
The first two chapters focus on the relationship between macroeconomic conditions and charitable giving and funding. Chapter One analyses the relationship between business cycles and private donations across charitable fields, building on and extending the approach of List and Peysakhovich (2011). Using autoregressive distributed lag (ARDL) and nonlinear ARDL (NARDL) models, the chapter finds that total donations and giving to Foundations increase with GDP growth, while donations to Relief of Poverty respond countercyclically. Panel analysis across ten provinces confirms the procyclicality of total donations and giving to Religion, and the countercyclicality of giving to Relief of Poverty during downturns. Asymmetric patterns are evident in Education at the national level and in Relief of Poverty at the provincial level.
Chapter Two examines how government funding to charities responds to macroeconomic conditions, using ARDL, NARDL, and panel models across federal, provincial, and municipal levels. The findings show that funding patterns vary by government tier, charity field, and business cycle phase. Federal funding is generally countercyclical, stabilising key sectors such as Relief of Poverty and Religion. In contrast, provincial and municipal funding is largely procyclical, targeting local priorities like Community and Health. Religion funding increases during downturns and remains stable during upturns, reflecting its role in supporting social cohesion. Education and Community funding rise with economic expansions, while Arts funding increases during contractions. In the Education sector, public funding closely follows GDP growth, with no clear evidence of crowding-in or crowding-out by private donations. In contrast, the Arts sector shows signs of crowding out, where increased government support appears to substitute for private giving. Overall, the chapter highlights the complex and field-specific ways in which public funding strategies interact with macroeconomic conditions.
Chapter Three shifts the focus to the spatial and temporal dynamics of charity entry and exit across Census Subdivisions. It examines how neighbourhood-level socio-economic conditions - such as poverty rates, expectations of government support, and the existing charity landscape - influence where and when charities form or close. Using a Poisson Pseudo Maximum Likelihood model with high-dimensional fixed effects, the analysis finds that charity entry is positively associated with local poverty and anticipated funding, particularly in need-responsive sectors like Relief of Poverty and Education. Exit, by contrast, is more closely tied to prior funding shortfalls. The chapter also identifies patterns of complementarity and substitution across charity types and shows that charities serving remote or underserved areas are more likely to enter in response to local needs. More broadly, the analysis reveals a mix of coordination and competition in both entry and exit dynamics. Extending the analysis to include a macroeconomic focus to tie into the earlier chapters, the chapter shows that charity entry and exit decisions respond to broader economic conditions, offering a macro-geographic perspective on the charitable sector
Mapping and Assessment of River Hydrokinetic Energy Resources Across Canada and the Global Arctic
No full textIn remote and northern communities across Canada and the Global Arctic, reliance on imported diesel for electricity continues to pose challenges including high costs, logistical constraints, environmental degradation, and vulnerability to fuel price volatility. Hydrokinetic energy (HKE), which harnesses the kinetic energy of flowing rivers without the need for dams, offers a locally available and lower-impact renewable energy alternative. Unlike conventional hydropower, HKE can provide electricity with comparatively minimal infrastructure and ecological disturbance, making it especially suitable for sensitive and remote locations. However, the adoption of HKE has been limited by the lack of reliable data and standardized methodologies for assessing site feasibility, particularly in remote and data-scarce regions. With increasing global interest in sustainable and community-based energy transitions, there is a growing need to robustly evaluate the feasibility of HKE deployment at regional, national, and local scales.
The primary aim of this research is to increase the visibility and viability of HKE as a renewable energy solution for communities located near rivers through detailed case studies and development of validated national and regional datasets. Specifically, this research has four objectives: (1) to review and synthesize the current state of HKE assessment methodologies with a focus on localized and regional approaches; (2) develop two high-resolution, validated HKE resource databases – one for all of Canada and another for the entire Global Arctic; (3) carry out full-scale, site-specific field assessments at diverse rivers, including those in remote and Arctic locations, to test current standards and methods; and (4) assess the socioeconomic readiness and feasibility of HKE deployment, particularly in the Arctic.
To achieve these objectives, a combination of literature review, remote sensing optimization, advanced GIS analysis, field data collection, hydrodynamic modeling, and socioeconomic analysis was employed. A comprehensive review identified methodological inconsistencies in localized and regional HKE assessments, highlighting the need for standardized methods and more uniform data integration. Surface water mapping approaches were developed and tested using Sentinel-1 Synthetic Aperture Radar and Sentinel-2 Multispectral Instrument satellite imagery across diverse Canadian landscapes, applying both spectral indices and machine learning classification techniques. These data and methods were evaluated to optimize waterbody detection accuracy. The insights from this work on remotely sensed data were then applied to update and improve the national HKE database for Canada by updating measurements of river width. This was performed through integrating newly available datasets and modern computational techniques, such as cloud-based satellite image processing. Key parameters to HKE estimation, including flow, depth, width, velocity, and power, were estimated at a notably increased spatial resolution and with a uniform methodology. This resulted in the development of the Canadian River Hydrokinetic Energy (CRHE) database, including 252,000 km of stream length. With estimates available at 1,325,261 cross sections in the database, an average spacing of 190 m between measurements was achieved. A similar approach was employed for estimating HKE resources in the Global Arctic. The updated databases for Canada and the Arctic were validated using HKE estimates derived from field measurements and hydrodynamic modeling. Field data was collected with an acoustic Doppler current profiler (ADCP) and real-time kinematic differential global positioning system (RTK-DGPS) for hydrodynamic model calibration using TELEMAC-2D software. Detailed site assessments at four rivers, including the Iqaluit Kuunga (Sylvia Grinnell) River and Rivière Rouge, evaluated flow dynamics, seasonal variability, and optimal turbine placement. Socioeconomic feasibility was examined through spatial analysis of Arctic communities, identifying 325 communities with promising HKE potential and analyzing variables such as resource proximity, local resource strength, and diesel offset potential.
The outcomes of this research include two validated, high-resolution HKE datasets – one for Canadian HKE resources and another for Global Arctic resources – that enable more accurate and accessible preliminary site identification by communities, developers, and policymakers. Remote sensing methods were optimized to produce improved estimates of river width, a critical input for HKE assessment, and practical recommendations are provided for future surface water mapping using remotely sensed data. Site-specific HKE resource assessments revealed the importance of capturing fine-scale spatial and temporal flow variations for optimal turbine placement, and demonstrated that reach-averaged velocities can significantly underestimate HKE potential. This study also offers guidance on field data collection techniques and HKE resource calculation practices. The Iqaluit Kuunga River case study confirmed the technical feasibility of HKE deployment in Arctic environments and proposed a framework for evaluating community readiness for energy transition across the Global Arctic. Collectively, the resulting datasets and recommendations lay a foundation for targeted, data-informed HKE development and support future renewable energy transitions in remote regions