- Thèses, 2011 - // Theses, 2011 -

Permanent URI for this collectionhttps://hdl.handle.net/10393/11105

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Within-Pangenome Phylogeny Based on Structural Variants
(Université d'Ottawa / University of Ottawa, 2026-06-01) Xu, Peng; Sankoff, David
Structural variations, particularly chromosomal inversions, are a major source of genomic diversity, yet their potential for phylogenetic reconstruction within pangenomes has not been fully established. This study examines the phylogenetic signal in inversion presence and absence patterns under a Dollo style evolutionary framework that assumes complex mutations arise once and are not regained. We analyzed two plant pangenomes, radish (Raphanus sativus) and cotton (Gossypium spp.). Large inversions were extracted from published resources and encoded as binary matrices. Using these matrices, we reconstructed phylogenies with the neighbour-joining method and compared them with published reference trees. The reference phylogeny for radish is based on sequence data, whereas the cotton reference tree was inferred from a genome-wide catalogue of structural variants. Tree similarity was assessed using three complementary measures: bipartition overlap, Maximum Agreement Subtree size, and co-phenetic correlation. The inversion-based trees did not fully reproduce the reference topologies, but they retained consistent internal structure. MAST analyses revealed subsets of accessions whose relationships were stable across trees, and co-phenetic correlations were clearly higher than expected under randomization. Simulation results further showed that stability under noise depends strongly on local structure. In particular, the preservation of sister pairs played a central role in maintaining agreement as the perturbation level increased. This work therefore contributes to a clearer understanding of what kinds of evolutionary information can and cannot be recovered from inversion data alone. The results indicate that inversions capture a meaningful, though incomplete, phylogenetic signal that is different from that provided by sequence data. Rather than viewing these differences as shortcomings, they reflect distinct evolutionary constraints acting on structural variation. Our analyses also show that split-based measures perform poorly on sparse SV data, while MAST and co-phenetic correlation provide more robust and interpretable assessments of tree similarity. Consequently, MAST and co-phenetic correlation offer a practical way to evaluate phylogenetic signal in sparse SV data and to distinguish evolutionary structure from technical noise.
Adsorption Performance and Cold Plasma Activation of Biochar for On-Site CH₄ Storage and Energy Recovery in Oil Fields
(Université d'Ottawa / University of Ottawa, 2026-06-01) Ko, Yoonhee; Lan, Christopher Q.
Routine flaring of associated petroleum gas (APG) remains a major source of greenhouse gas emissions in upstream oil production, particularly at remote or infrastructure-limited production sites where gas transportation and processing are uneconomic. Developing a field-deployable, integrated utilization pathway that captures methane (CH₄)-rich APG for on-site generation of electricity and heat at low cost could significantly reduce energy consumption and greenhouse gas (GHG) emissions across the oil industry. This thesis evaluates biochar as an adsorbent for capturing and storing CH₄ and cold plasma surface modification as a means of enhancing CH₄ adsorption, upgrading low-cost biomass-derived chars as effective adsorbents for such a system. CH₄ adsorption performance was measured for four biochars and compared against that of three commercial activated carbons. While the pristine biochars exhibited adsorption capacities at least 50% lower than those of the tested activated carbons, they demonstrated more than twice the CH₄ storage capacity of compressed natural gas (CNG) at equivalent pressure and vessel volume (10-75 bar), demonstrating their potential to reduce compression requirements and avoid heavy high-pressure storage vessels in field applications. Adsorption thermodynamics and kinetics were analyzed to establish performance baselines and implications for adsorbed natural gas (ANG) storage. To improve CH₄ storage performance of biochars, this work further investigated cold dielectric barrier discharge (DBD) plasma as a solvent-free, low-temperature surface modification technique. Three key findings emerged: the optimal plasma duration was 30 minutes; the initial volatile matter content of biochar directly governs plasma modification efficiency; and Ar plasma is the most effective source gas, increasing CH₄ adsorption capacity by up to 73%. It was also demonstrated that O₂ in plasma gas (i.e., air or O₂/He) led to a reduction in plasma effectiveness. Results indicate that the enhancement is associated with an increase in the specific surface area of biochars driven by the development of ultramicropores (<0.68 nm), which is in turn associated with the removal of organic impurities from biochar surfaces. Evidence indicates that the morphology, especially the width of pore entrances, may govern the adsorption effectiveness of biochars. Finally, the research evaluated the end-of-life utilization of spent biochars. Multicycle adsorption tests showed that the adsorption performance of biochars degraded with repeated cycles. However, the degraded biochars can still store more methane volumetrically than compressed gas vessels at low to medium pressures relevant to oil and gas fields. Spent biochars retained residual CH₄, which increased calorific value (e.g. from 13.88 to 18.62 kJ/g) and reduced ignition temperatures (e.g. from 320 °C to 250 °C), supporting their reuse as an enhanced solid fuel. This work demonstrates a laboratory-scale proof-of-concept that integrates emission abatement, energy recovery, and circular material use. If future work achieves techno-economic optimization, multicomponent gas validation, and successful scale-up of plasma treatment, this approach could potentially contribute to reducing the lifecycle GHG footprint of remote oil field operations. Significant engineering and economic development remains before field deployment feasibility can be assessed.
Intelligent Fault Diagnosis and Health State Recognition of Rotating Machinery Under Variable Working Conditions Using Deep Transfer Learning
(Université d'Ottawa / University of Ottawa, 2026-05-29) Hua, Zehui; Dumond, Patrick
The health of key rotating components in machinery systems, such as rolling element bearings and gears, is critical for meeting design requirements and ensuring safe operation. These components degrade over time, leading to faults that can cause unplanned downtime, economic loss, or catastrophic accidents. Vibration signal-based intelligent fault diagnosis (IFD) enables real-time condition monitoring with reduced reliance on human expertise. However, traditional machine learning methods often assume that vibration data from a source domain and a target domain share similar feature distributions, an assumption that rarely holds under variable working conditions in industrial settings. Transfer learning mitigates distribution discrepancies, yet important challenges remain: (1) effective IFD under changing operating conditions, (2) learning models that generalize across multiple domains simultaneously, and (3) transferring knowledge to a totally unseen target domain. This thesis investigates domain generalization for vibration-based IFD under distribution shifts induced by variable working conditions and develops four methods. First, by leveraging inter- and intra-domain invariances, condition-robust representations are learned and achieve consistent improvements over strong baselines on two benchmark datasets across diverse cross-condition settings. Second, to better handle operating-condition variations, a multi-subdomain alignment strategy that introduces multiple condition-related subdomains within a single source domain and aligns them to reduce condition-dependent discrepancies is proposed, improving diagnostic performance on two bearing datasets. Third, a feature disentanglement mechanism is introduced to decouple domain-invariant from domain-specific features, enhancing discriminability and robustness under unseen conditions. Extensive experiments, including low-data regimes, show superiority over several state-of-the-art approaches. Finally, the framework for simulation-to-experiment transfer is extended, and a transferable diagnostic model that captures time-varying characteristics is developed, enabling reliable fault detection based on the obtained time-frequency representations.
La valeur du français dans les bureaux d'avocates et d'avocats au Nouveau-Brunswick : d'un powerless language à une ressource marchandable
(Université d'Ottawa / University of Ottawa, 2026-05-29) Léger, Luc; McLaughlin, Mireille
L'établissement du bilinguisme judiciaire au Nouveau-Brunswick s'inscrit dans un projet visant l'égalité des deux communautés de langues officielles de la province. La Loi sur les langues officielles (1969), qui a reconnu le droit des individus de s'exprimer devant les tribunaux dans la langue officielle de leur choix, a remis en question le monopole historique de l'anglais dans la tradition de la Common Law. Malgré cette reconnaissance, le français est resté un powerless language (O'Barr et al., 1980), c'est-à-dire une langue sans valeur dans le monde de la justice, jusqu'au début des années 1980. Grâce à l'enseignement de la Common Law en français, l'adaptation du vocabulaire juridique et la traduction des lois et des décisions de justice, le français a gagné en notoriété. À partir de ce moment, le français est devenu une ressource convoitée par les avocates et les avocats propriétaires pour faire du profit et répondre aux besoins exprimés sur le marché linguistique (Bourdieu, 1982). Cependant, cette reconnaissance du français demeure conditionnelle à la maîtrise de l'anglais entraînant l'exclusion de toutes les personnes candidates unilingues francophones, même celles qui maîtrisent le français standard, et de toutes les personnes candidates qui n'ont pas un bilinguisme qui se rapproche de l'idéal du double monolinguisme (Heller, 1999). Cette thèse s'intéresse à la valorisation croissante du français dans les bureaux d'avocates et d'avocats, à ses effets sur les représentations linguistiques des travailleuses et des travailleurs et au monde juridique comme espace dans lequel se négocie la valeur des pratiques langagières, contribuant à produire et à reproduire des inégalités sociales (Heller, 2002). Située entre la sociolinguistique et la sociologie politique, cette thèse met en lumière les tensions entre les objectifs politiques et les logiques de marchandisation langagière.
Analyse décoloniale de l'itinéraire thérapeutique périnatal des femmes Haïtiennes de 2019 à 2023
(Université d'Ottawa / University of Ottawa, 2026-05-29) Bien-Aime, Edwige; Mondain, Nathalie
Dans cette thèse de maîtrise, j'analyse comment les femmes haïtiennes, ayant un niveau secondaire et plus du département de l'Ouest, naviguent à travers les soins disponibles de 2019 à 2023 : une période marquée par une déstructuration politique. À travers la méthodologie enracinée et des entretiens semi-directifs en ligne auprès de neuf personnes : sept femmes et deux prestataires de soins. J'explore les défis des femmes ainsi que leurs stratégies pour construire leurs itinéraires. Cette analyse s'inscrit dans une approche décoloniale du fait qu'elle vise d'abord, à rendre visibles des pratiques disqualifiées par le système sanitaire biomédical haïtien alors que les femmes haïtiennes y recourent même dans un milieu médicalisé. Ensuite, elle soulève la question de la reproduction des rapports coloniaux dans les établissements de soins périnataux. Le résultat de cette recherche permet de conclure que les femmes combinent les soins dans plusieurs registres : en établissement, automédication, soins à domicile, selon l'étape de la périnatalité, leur appartenance religieuse et la méthode d'accouchement pour répondre à leurs besoins physiques, mentaux et spirituels.
Sexual and Reproductive Violence as Genocide and the Prevention of Genocide in Contemporary Asia: The Cases of the Rohingya and the Uyghurs
(Université d'Ottawa / University of Ottawa, 2026-05-29) Tiunn, Hokbi; Packer, John
Building on feminist international legal scholarship, this dissertation begins from the observation that international law has long been shaped by male-centric frameworks that marginalize women's experiences and treat harms associated with women as peripheral to human suffering. It argues that this gendered framing has also distorted how genocide is legally understood and recognized. Although Article II of the Genocide Convention identifies five genocidal acts without formally ranking their severity, legal and political recognition of genocide has often privileged killing over non-lethal forms of group destruction, despite their devastating and often gendered effects. To address these omissions, this dissertation introduces the concept of genocidal patriarchy: a specific genocidal logic that weaponizes women in the destruction of the group. Women become central to genocidal violence not because they are reducible to their bodies or reproductive roles, but because patriarchal orders make their position within the group socially and politically consequential. The dissertation further examines the triple vulnerabilities borne by women in genocide: their exposure to external state violence as members of protected groups; their vulnerability within patriarchal social orders that attach group meaning to women; and their marginalization within international legal frameworks that continue to privilege male-centered experiences of harm. These intersecting vulnerabilities help explain why women may be central to the logic of genocidal destruction while remaining only partially visible within the legal frameworks designed to prevent and punish genocide. Through the cases of the Rohingya in Myanmar and the Uyghurs in China, this dissertation examines how genocidal patriarchy manifests in contemporary atrocity contexts. These cases show how different forms of gendered violence and governance may converge within broader patterns of genocide. The dissertation calls for a rethinking of genocide law that attends not only to killing, but also to gendered forms of violence that attack the group as such.
Neural Architectures and Approaches for Person Re-Identification in Autonomous Surveillance System
(Université d'Ottawa / University of Ottawa, 2026-05-29) AlGhamdi, Hamzah; Laganière, Robert
Video-based person re-identification is the task of recognizing the same person across different cameras and video clips. It is an important part of automated surveillance systems because a person may disappear from one camera, become partially blocked, or reappear later in another camera view. This task is difficult because people can look different when the camera angle, lighting, distance, background, or body pose changes. This thesis studies how video-based person re-identification can be improved under three practical deployment conditions. First, it presents a resource-aware method for cases where only a small amount of labelled data is available. The method begins with one labelled video clip per person and gradually adds reliable, automatically labelled examples to improve training while keeping the model efficient. Second, it develops a fully supervised method for cases where labelled training data are available. This model uses information from the entire video sequence as well as local body-region details to improve recognition under occlusion, pose changes, and background clutter. Third, it introduces a transfer-based method for cases where a model trained on one camera network must be used in another network without new manual labels. This method helps the model recognize people more reliably when the camera setup, viewing angle, lighting, or background changes. Experiments on several video-based person re-identification datasets show that the proposed methods improve performance under different levels of supervision, computational cost, and camera variation. Overall, the thesis provides a practical study of how video-based person re-identification systems can be designed for label-scarce, fully labelled, and cross-camera deployment settings.
The Role of Social Media on Body Image and Self-Perception Among Young Sri Lankan Women
(Université d'Ottawa / University of Ottawa, 2026-05-27) Serasinghe, Chamathi; Peker, Efe
This study examines the role of social media, particularly Instagram, in shaping body image and self-perception among Sri Lankan young women. Drawing on an intersectional feminist lens, the research explores how gender, race, class and cultural context interact to influence women's experiences of beauty standards and gender norms in digital spaces. A qualitative research design was employed, using in-depth interviews and social media content analysis to capture both personal experiences and the broader digital environment. Thematic analysis was used to identify key patterns and themes in the data. The findings reveal that Instagram functions as a complex and contested space. First, it acts as a platform for social comparison, where participants frequently evaluate their appearance against idealized images. Second, the study highlights the persistence of racialized beauty ideals, particularly the privileging of lighter skin tones and Eurocentric features. Third, some participants reported developing greater acceptance of their natural bodies, although it was often shaped by economic and practical constraints. Finally, the study demonstrates the dual role of social media in both reinforcing traditional gender norms and promoting more empowering and egalitarian representations. Contributing to the limited literature on the impact of social media on body image and self-perception in the Sri Lankan context, this study highlights the importance of considering intersecting social factors. Overall, the findings emphasize that social media is not a neutral space but one where body image and self-perception are continuously shaped and negotiated.
Ecotoxicological and Metabolism-Disrupting Actions of Bacillus thuringiensis israelensis and Deltamethrin Insecticides in Anuran Tadpoles
(Université d'Ottawa / University of Ottawa, 2026-05-27) Empey, Madelaine; Trudeau, Vance L.
Endocrine-disrupting chemicals are an increasing environmental concern due to their capacity to disrupt physiological processes, including growth, development, and metabolism. The insecticides VectoBac® 200G (a Bacillus thuringiensis israelensis (Bti) product) and deltamethrin (a pyrethroid) are widely used for mosquito control, but little research has examined their effects on amphibians. Here, we tested the hypothesis that VectoBac® 200G and deltamethrin adversely affect tadpole health and development via metabolic disruption. First, we assessed the toxicity of these insecticides on three North American species: the chorus frog (Pseudacris maculata), the leopard frog (Lithobates pipiens), and the wood frog (Lithobates sylvaticus). The 96 h median lethal concentration (LC50) values were estimated to be 513,000 ± 1.15, 78,860 ± 1.10, and 525,363.4 ± 1.13 international toxic units (ITU)/L for chorus, leopard, and wood frog tadpoles exposed to VectoBac® 200G. The LC50 values for deltamethrin were estimated to be 2.69 ± 1.06, 7.30 ± 1.05, and 1.15 ± 1.06 μg active ingredient (a.i.)/L for chorus, leopard, and wood frog tadpoles, respectively. VectoBac® 200G and deltamethrin had varying effects on total length, and investigations on metabolic endpoints were pursued in the wood frog tadpole. Metabolic studies on tadpoles are sparse, and the biggest challenge was measuring blood glucose, as wood frog tadpoles are too small to collect blood from. We therefore designed and validated a novel assay that enables measurement of whole-body glucose in individual tadpoles. Following 30-day exposures, VectoBac® 200G significantly increased glucose uptake, whereas exposure to deltamethrin did not. Chronic exposure from the early larval stage through metamorphosis delayed time to complete metamorphosis in VectoBac® 200G-exposed tadpoles, and tadpoles exposed to both insecticides displayed altered hepatic lipid accumulation. These results further suggested that metabolic endpoints were altered from exposure, especially to VectoBac® 200G. To investigate pancreatic effects, a novel custom antibody targeting the frog insulin B-chain was generated and validated. Both insecticides increased the proportion and nuclear radius of pancreatic beta-cells in exposed wood frogs. Only VectoBac® 200G increased total insulin-positive staining per pancreas; however, insulin staining per beta-cell decreased. Increased beta-cell proliferation combined with reduced insulin staining per cell suggests altered insulin dynamics in VectoBac® 200G-exposed frogs. Collectively, these results address data gaps for both Bti and deltamethrin insecticides and provide insight into potential mechanisms by which these products may disrupt amphibian metabolism.
Women's Subjective Orgasm Experience over Adulthood, with a Focus on Later Life
(Université d'Ottawa / University of Ottawa, 2026-05-27) Webb, Amy; Reissing, Elke D.
Rather than fading with age, women's sexuality in later life is now being acknowledged as an important and rewarding dimension of health and well-being. Orgasm is central to sexual pleasure, but its subjective experience (SOE) remains poorly understood. Most research has emphasized frequency, dysfunction, or physiology, with limited attention to the psychological, sensory, physical, and relational dimensions of orgasm. Although many older women remain sexually active, the influence of menopause and sexual context (solitary vs. partnered) on SOE has not been examined, and validated measures for older women are lacking. This dissertation addresses these gaps through two complementary studies. Study 1 evaluated the psychometric properties of the Orgasm Rating Scale (ORS) and the Bodily Sensations of Orgasm Scale (BSOS) among pre-, peri-, and post-menopausal women. Factor analyses supported a 10-factor structure for the ORS and a 3-factor structure for the BSOS across solitary and partnered contexts. Measurement invariance testing confirmed that both measures are interpreted consistently across menopausal status groups, supporting their validity for use throughout adulthood. Study 2 applied these measures to compare SOE across adulthood and sexual context, supplemented with qualitative reflections from post-menopausal women. Results showed that post-menopausal women reported fewer physical sensations, yet intensity remained stable across groups. Pre-menopausal women reported greater effort to reach orgasm, and across all groups, partnered orgasms were rated higher than solitary orgasms. Qualitative findings underscored diversity in later-life experiences, challenging assumptions of decline and emphasizing relational and situational influences. Together, these studies validate comprehensive measures of SOE across adulthood and provide new insights into women's orgasm over the lifespan. Clinically, findings highlight the need to distinguish age-related changes from dysfunction and to consider partner-related factors in assessment. Theoretically, they refine the Multidimensional Model of the SOE and demonstrate the utility of validated measures across adulthood. Societally, they challenge deficit-based narratives of sexual decline and call for strengths-focused perspectives that reflect the diversity of women's sexual realities in later life.
Essays on Empirical Corporate Finance
(Université d'Ottawa / University of Ottawa, 2026-05-27) Shabani, Sahar; Akyol, Ali C.; Racicot, François-Eric
In this dissertation, I examine important questions in empirical corporate finance. The research topics include "Words before exit": CEO linguistic patterns and forced turnover outcomes in the first chapter, "Interlocks in the shadow": how big firms lead information flow in the second chapter, and "What do all these vice presidents do?": the costs and benefits of senior executive employment in the third chapter. All chapters are co-authored with Professor Ali Akyol. The first chapter examines CEO language style during the final earnings conference calls before forced turnovers to identify speech patterns that precede dismissal and assess whether linguistic attributes can serve as predictive signals of forced turnover. Our findings reveal that CEOs nearing dismissal display distinct verbal communication patterns compared to their peers who retain their positions. Specifically, increased use of first-person pronouns, analytical language, power-related words, and a present-focused orientation is associated with a higher likelihood of forced turnover. In contrast, greater use of third-person pronouns, authentic language, affective words, and tentative language correlates with a lower likelihood of dismissal. These results remain robust when comparing fired CEOs to similarly situated retained CEOs using propensity score matching, entropy balancing, and difference-in-difference analyses. Furthermore, our analysis shows that these linguistic shifts are specific to CEOs, as CFOs do not display similar patterns. Additionally, we find that new CEOs following forced turnovers exhibit distinct communication styles compared to their ousted predecessors. The second chapter investigates how information flows through board interlocks in corporate networks, focusing on the asymmetric influence of larger firms on smaller connected firms. We use the COVID-19 pandemic as a natural experiment, as the rare event of earnings guidance withdrawals surged due to heightened uncertainty and economic volatility, creating a unique setting to study disclosure behavior. Analyzing a sample of U.S. public firms, we find that smaller firms are significantly more likely to withdraw earnings guidance after larger, connected peers do especially when connected through experienced audit committee members. These findings reveal that information transmission via interlocks is asymmetric, driven by firm size and director expertise, and that such effects become more visible during periods of crisis. In the third chapter, we examine when senior executive employment creates or destroys shareholder value by studying vice president (VP) in U.S. public firms. Using comprehensive data from 2005-2024, we construct industry-adjusted measures of excess VP employment relative to economically comparable peers. We find that excess VP employment is associated with lower firm value on average, but this relation varies systematically with firm characteristic, market conditions and considering governance measures. In particular, excess VP employment is positively associated with firm value in large firms and during periods of heightened economic stress. These findings are robust to a range of identification and robustness tests, including matching-based approaches, instrumental variables, and alternative peer benchmarks.
Corporate Harm to Communities and Director Liability: A Comparison of Italy and Canada
(Université d'Ottawa / University of Ottawa, 2026-05-27) De Chirico, Clara; Vasudev, P. M.
This research investigates corporate harm to local communities between Italy and Canada to strengthen their protection through corporate governance measures. Despite growing regulatory pressure for corporations to limit socio-environmental impacts, Italy offers only limited safeguards to prevent or remedy such harm. Adopting a commons-inspired theoretical framework and undertaking comparative analysis with Canada - where stakeholder-oriented corporate governance has been widely debated in law and scholarship - the research asks whether Italian corporate law provides a basis for recognizing a director's duty not to harm negatively affected communities. The study concludes affirmatively, identifying directors' duty to establish and implement adequate risk-management arrangements - a subtype of the duty of care - as a suitable statutory foundation. This conclusion is reinforced through analysis of Canadian cases and scholarly critiques, offering a robust legal and argumentative basis to affirm sustainability-oriented obligations for directors in Italy and extending prior scholarly proposals. Additional contributions include theoretical and methodological innovation and the development of a general framework for identifying communities as corporate stakeholders, which can guide the practical implementation of the proposal and support future research on corporate obligations towards local communities. Overall, the research shows how progressive statutory interpretation, based on inclusive conceptual considerations and supported by comparative insights, can inform legal innovation and enhance protections for communities impacted by corporate activity, providing pathways for advancing stakeholder-oriented governance in Italy.
Understanding Problem Difficulty in Reinforcement Learning: A Study of Goal-Oriented MDPs and Solution Methods
(Université d'Ottawa / University of Ottawa, 2026-05-26) Beeler, Christopher; Fraser, Maia; Tamblyn, Isaac
Due to the rise of optimal control problems in modern life and their increasing complexity, this thesis analyzes various properties of these problems and how they relate to the difficulty of the problem itself to help increase understanding of the space. Through the lenses of learning theory and topology, it discusses how concepts like sample complexity, topological complexity, and path homotopy contribute to characterizing problem difficulty. Through graphical and topologically equivalent representations, methods are presented for bounding sample complexity for various goal-oriented MDPs, with a strong focus on separated-path MDPs. Using various model environments as specific examples of interest, three different methods of solving these types of problems are presented along with discussions on why the above properties affect those solutions. These environments serve as playgrounds for analyses based on partial observability, topologically complex navigation, and hierarchical frameworks.
Transdisciplinary - STEAM Design Toolkit: Leveraging the Benefits of Artistic Approaches in Multidisciplinary Collaborations
(Université d'Ottawa | University of Ottawa, 2026-05-26) Rodier, Chantal; Millar, Jason
Complex global challenges such as climate change, technological disruption, and social inequality increasingly require collaboration across disciplinary boundaries. While STEAM (Science, Technology, Engineering, Arts, and Mathematics) initiatives promise richer perspectives and innovative solutions, assembling and sustaining transdisciplinary design teams that successfully integrate diverse epistemologies remains difficult. Disciplinary co-presence alone does not guarantee integration; carefully designed epistemic and relational conditions are required. This dissertation addresses this challenge through a seven-year longitudinal action research study conducted in higher education design courses. It argues that art and artistic practices, when authentically integrated with other disciplines, enhance the transformative capacity of transdisciplinary STEAM collaborations. Across seven iterative Plan–Act–Observe–Reflect cycles, the research developed and refined the Transdisciplinary STEAM Design Toolkit (TD-SDT) —a framework conceived not as a prescriptive method but as an epistemic infrastructure designed to enable transdisciplinary knowledge creation. Empirical analysis revealed that effective transdisciplinary collaboration depends on three interacting conditions: epistemic conditions which encourage reflexive examination of disciplinary assumptions, relational conditions which sustain trust and enable productive friction, and pedagogical conditions which scaffold collaborative inquiry through structured design processes. Within such environments, integration occurs through mechanisms of epistemic crossing, a process through which participants move beyond disciplinary perspectives to construct shared conceptual spaces. Key epistemic mediators include abstraction, narrative reframing, boundary objects, artistic inquiry, and symbolic infrastructures. Methodologically, the study introduces the TD Process Assessment Framework, a structured yet complexity-sensitive approach for evaluating both collaborative process quality and integration depth. The framework combines quantitative assessment of transdisciplinary dimensions with qualitative triangulation across artifacts, reflections, and observational data. Theoretically, the TD-SDT operationalises a Constructivism–Systems Thinking–Complexity (CSC) framework and extends reflexivity-based models of collaboration toward the concept of epistemic innovation, describing how new integrative understandings emerge through sustained epistemic crossing. The findings also reposition the arts as epistemic infrastructure within STEAM collaboration, demonstrating their role in sustaining ambiguity, activating productive friction, and enabling epistemic movement across disciplinary boundaries. Together, these contributions advance a coherent model for cultivating transdisciplinary collaboration in complex design contexts and provide educators, researchers, and practitioners with both conceptual guidance and an assessable infrastructure for supporting integrative knowledge creation.
Heat Sink Performance of Electrodeposited Copper-Diamond Composites
(Université d'Ottawa / University of Ottawa, 2026-05-22) Syed, Hussain; Cho, Hai Jun
The rapid advancement of modern electronics has intensified thermal management challenges, driving the need for heat sink materials with high thermal conductivity and efficient heat removal. Electrodeposited copper-diamond (Cu-D) composites show strong potential for next-generation electronic applications, offering thermal conductivities exceeding those of conventional metals while remaining more economical than composites produced through high-temperature-high-pressure methods. Despite this promise, most studies emphasize intrinsic material properties rather than evaluating practical cooling performance. This thesis investigates the heat sink behavior of electrodeposited Cu-D composites under realistic operating conditions using LED junction-to-ambient thermal resistance. Cu-D samples containing uncoated and TiC-coated diamond particles, arranged in single-layer and multi-layer architectures, were fabricated and assessed. Uncoated composites exhibited poorer heat sink performance than pure copper due to small, equiaxed copper grains near the Cu-D interface, which limited thermal boundary conductance despite being free of interfacial voids. In contrast, TiC-coated diamond particles significantly lowered steady-state LED temperatures, demonstrating the importance of interfacial engineering in improving phonon transport across metal-diamond interfaces. The influence of thermal interface materials (TIMs) was also examined. Incorporating 10-30 wt.% diamond particles into the commercial thermal paste further reduced LED temperatures, even though the thicker bond-line would typically increase thermal resistance. This shows that TIM formulation plays an additional role in determining overall heat sink effectiveness. Overall, this work advances electrodeposited Cu-D composites toward practical heat sink applications and shows that interfacial coatings, copper microstructure, and TIM design collectively influence thermal performance.
Are We the People? : A Contextualized Theory of Voting for Non-Resident Citizens
(Université d'Ottawa / University of Ottawa, 2026-05-22) Burton, Sarah; Pal, Michael
This thesis presents a contextualized account of non-resident citizen enfranchisement that, I argue, is both constitutionally and democratically defensible. While the practice of non-resident citizen voting has expanded exponentially over the last half century, it remains undertheorized. Within democratic theory, the practice tends to be normatively rejected on the basis that citizenship-based voting is a relic of outdated nationalisms, and that non-resident citizens are not sufficiently subject to the laws that will be created. In constitutional courtrooms, however, despite significant democratic, logistical and institutional barriers, the right of non-resident citizens to vote in national elections has been overwhelmingly affirmed. By comparing the analyses in five constitutional apex courts, I argue that that this overwhelming support is driven by (1) the constitutional framing of the citizen as the source of all state authority, and (2) a vigorously protective judiciary. In other words, laws which exclude citizens from the demos are constitutionally impermissible, and legislated dividing lines that separate voting from non-voting citizens are too blunt and arbitrary. I argue that judges rightfully adopt a skeptical posture towards legislated disenfranchisement. However, their statements about the absolute nature of the citizen's right to vote are not only wrong as a matter of fact, they open the door to political manipulation of the electorate in ways that undermine the rights they are seeking to protect. Democratic theories have compelling accounts of membership that can help rectify this failing. However, given their skepticism of citizenship-based voting, these accounts have not penetrated the constitutional courtroom. By probing these accounts, I argue that Rainer Bauböck's stakeholder citizen model is able to impose meaningful democratic guardrails onto the practice of non-resident citizen voting in a way that is constitutionally acceptable. In order to survive vigorous scrutiny, however, Bauböck's account must be modified. The output of this investigation is my Constitutional Stakeholder model. It argues that restrictions on non-resident citizen voting can be constitutionally acceptable so long as they are justified by reference to a citizen stakeholding understanding of democratic membership. However, in order to withstand vigorous constitutional analysis, lines separating voting from non-voting citizens cannot be blunt or arbitrary. In practice, this means that in order to be constitutionally upheld, non-resident citizens on the wrong side of a legislated dividing line must have a path by which they can demonstrate their rightful inclusion in the demos. To assuage critiques that such individuation is unworkable, my solution is derived from models that are already in place in other countries.
Graphene Oxide-Based Gene Delivery Strategies for Cancer-Specific Elimination in 3D Lung Tumor Models
(Université d'Ottawa | University of Ottawa, 2026-05-22) Grilli, Francesca; Variola, Fabio; Zou, Shan
Solid tumors develop within highly complex three-dimensional (3D) microenvironments, in which cancer cells interact dynamically with stromal cells, immune populations, and extracellular matrix (ECM) components. These interactions critically regulate tumor progression, immune evasion, and therapeutic resistance, yet are not adequately captured by conventional two-dimensional (2D) in vitro models. Despite significant advances in anticancer therapies, the clinical translation of many promising strategies remains limited by the lack of selectivity for cancer cells. As a result, therapeutic efficacy is often overestimated, while resistance mechanisms and effects on non-target cell populations remain insufficiently understood. Gene therapy has emerged as a powerful approach to modulate cancer-associated pathways, particularly those governing immune evasion and apoptosis. By controlling gene expression in cancer cells, gene-based strategies can suppress tumor growth and enhance immune-mediated cancer cell elimination while reducing impacts on healthy tissues. Among emerging nanomaterials, graphene oxide (GO) has attracted increasing interest as a nanocarrier platform for gene delivery due to its high loading capacity, tunable surface functionalization, and promising biocompatibility. The goal of this doctoral work was to establish an integrated platform combining GO-based gene delivery with progressively complex 3D lung cancer models, enabling the rational design, evaluation, and refinement of cancer-specific therapeutic strategies. This work is structured around three interrelated pillars: nanocarrier engineering, tumor microenvironment modeling, and therapy strategy design, which are explored iteratively throughout the thesis. First, GO nanocarrier formulations were systematically engineered and evaluated to identify those providing optimal biocompatibility and transfection efficiency. The effects of nanocarrier size and surface modification with polyethylene glycol (PEG) and polyamidoamine (PAMAM) were assessed for small interfering RNA (siRNA) delivery in both conventional 2D cultures and 3D lung cancer spheroids. Cellular viability, apoptosis, and target protein modulation were analyzed to elucidate how nanocarrier physicochemical properties influence delivery performance. Building on this optimized delivery system, an increasingly physiologically relevant multicellular 3D lung tumor model was developed by integrating cancer cells, stromal fibroblasts, and macrophages within an ECM-mimetic scaffold. GO nanocarriers delivered distinct therapeutic cargos, including siRNA and plasmid DNA (pDNA), targeting immune evasion and apoptotic pathways through single-gene and co-delivery strategies. Analysis of nanocarrier uptake, gene and protein modulation, and cancer cell viability demonstrated that co-delivery approaches enhance cancer cell elimination while limiting off-target effects within a tumor-stroma-immune-rich microenvironment. Finally, the optimized nanocarrier and advanced 3D tumor model were unified into a single platform, enabling multi-gene delivery targeting cancer cells, stromal support, and immune-mediated responses simultaneously. To further enhance cancer cell specificity, GO was functionalized with an epidermal growth factor receptor (EGFR)-targeting peptide. Therapeutic outcomes were evaluated through cell type-specific nanocarrier uptake, targeted gene modulation, macrophage activation, stromal remodeling, and apoptosis induction. Coordinated modulation of multiple tumor components led to enhanced cancer-specific elimination, compared to single-target approaches. This thesis demonstrates that effective cancer-specific gene therapy requires the concurrent optimization of nanocarrier design, tumor model complexity, and multi-target therapeutic strategies. By integrating these elements within a unified 3D evaluation framework, this work establishes GO-based gene delivery systems as versatile, microenvironment-aware tools for preclinical evaluation and rational development of next-generation cancer therapies.
L’utilisation du sport comme soft power par les puissances autoritaires : une comparaison des cas chinois et saoudien
(Université d'Ottawa | University of Ottawa, 2026-05-22) Laberge, Marie; Massot, Pascale
La Chine et l’Arabie saoudite sont deux puissances autoritaires utilisant le sport comme outil de soft power. La réception de leur soft power respectif dans les pays occidentaux, particulièrement aux États-Unis, est cependant bien différente. À l’aide d’une analyse dans le temps des discours de deux journaux américains, cette thèse étudie l’évolution de la réception des tentatives de soft power sportif chinois et saoudien. Constatant d’abord que la réception résulte de l’état des relations politiques entre les pays, comme identifié dans le discours médiatique plus négatif du soft power chinois par rapport à celui de l’Arabie saoudite, l’analyse des discours médiatiques a également permis de constater que cette réception devenait plus négative au fil des années. L’autoritarisme plus affirmé de la part de la Chine et de l’Arabie saoudite, ainsi que le rejet des valeurs libérales par ces États, enrayent la réception du soft power sportif aux États-Unis. China and Saudi Arabia are two authoritarian powers that use sport as a tool of soft power. However, the reception of their respective soft power in Western countries, particularly the United States, is quite different. Through the analysis of the discourses of two American newspapers, this thesis examines the evolution of Chinese and Saudi Arabia attempts at sport soft power. Initially observing that reception stems from the state of political relations between the countries, as evidenced by the more negative media discourse surrounding Chinese soft power compared to Saudi Arabia’s, the analysis of media discourse also reveals that reception has become increasingly negative over the years.The increasingly assertive authoritarianism of China and Saudi Arabia, coupled with their rejection of liberal values by both regimes, hinder the reception of sport soft power in the United States.
Multi-Objective Optimization to Improve Structure-Based Virtual Screening at Large Scale
(Université d'Ottawa | University of Ottawa, 2026-05-21) Skorupan, Stasa; Gentile, Francesco
The recent expansion of commercial, chemical databases to billions of make-on demand molecules has restructured hit identification methods in early-stage drug discovery. The exploration of these ultra-large chemical databases represents a new frontier for the identification of novel, potent, and selective drug candidates. Molecular docking is a computational technique used to predict the binding modes and affinities of small molecules to a protein binding site, enabling fast and cost-effective virtual screening (VS) of large chemical libraries to identify novel hit compounds. Machine learning (ML)-augmented molecular docking methods were proposed as a new paradigm to screen ultra-large, commercial, chemical libraries and expand VS to billions of molecules. These models are generally trained on a small subset of docked protein- ligand complexes to predict binding affinities of the remainder of the dataset, thereby streamlining the identification of promising top-scoring candidates at reasonable computational costs. Molecular docking continues to be crucial in the acceleration and cost-effectiveness of hit identification. However, the simplified modelling of protein-ligand interactions introduces a significant number of artifact molecules, especially for ultra-large libraries, with the visual inspection of the top-ranked docking hits being the standard protocol to remove these artifacts. Common criteria considered in the assessment of modelled protein-ligand binding includes strain and unsatisfied polar ligand or protein heteroatoms and thus, various computational tools have been developed to automate this filtering process at scale. Moreover, ML-accelerated docking models can implicitly learn and propagate these inherent molecular docking artifacts. Importantly, no current model addresses the effect of artifacts inherent to molecular docking predictions performed at large scale. The research herein developed new multi-objective optimization (MOO), ML-accelerated molecular docking models to aid in artifact filtering and selection of promising candidates in the early stages of drug discovery. These models incorporate selected three-dimensional medicinal chemistry properties that were thoroughly evaluated for their potential to improve early enrichment in VS. Chapter 2 presents a retrospective evaluation of ligand strain and unsatisfied hydrogen bonds as filters in the post-processing of molecular dockings to assess the impact on early enrichment. We found their effect on enrichment to be highly system-dependent: there was no single threshold that led to an enrichment of all protein-ligand datasets explored, but several proteins showed significant enrichment when using strain, unsatisfied hydrogen bonds, or both as filters at specific thresholds. Chapter 3 presents simulated large-scale prospective VS campaigns with the developed MOO ML-accelerated molecular docking models and selected three- dimensional medicinal chemistry filters. Multi-task learning (MTL) was explored to this end. In most systems studied, there was an improvement in early enrichment with filtering compared to molecular docking score predictions alone. MTL models showed the potential to improve early enrichment in large-scale VS, while accelerating runtime (3-4x) and significantly reducing (90- 99%) the chemical database size. This research contributes an open-source, medicinal chemistry- informed ML-accelerated molecular docking model towards the development of new drug discovery tools.
Evaluating Load Carriage System Static Fit in Canadian Armed Forces Soldiers
(Université d'Ottawa | University of Ottawa, 2026-05-21) Solano Ocampo, Domenica; Graham, Ryan
Load carriage systems (LCSs) are critical to soldier performance and safety; however, their effectiveness is often compromised by poor fit and discomfort during use. Poorly fitting equipment has been associated with reduced mobility, increased discomfort, and elevated risk of musculoskeletal injury, highlighting the need for improved evaluation approaches. While objective methods exist to quantify body–equipment interaction, subjective evaluations remain essential for understanding user experience in applied military settings. This thesis aimed to (1) identify which aspects of perceived fit and comfort most strongly influence overall equipment acceptability, and (2) compare these perceptions across LCS configurations, specifically between the current in-service Clothe the Soldier (CTS) system and the newer Body Armour Carriage System (BACS). Subjective responses were collected from Canadian Armed Forces soldiers across 10 equipped configurations using structured surveys that assessed regional fit, comfort, and overall acceptability. Linear mixed-effects models were used to evaluate differences between configurations and examine predictive relationships between variables. Results demonstrated significant differences across configurations, with BACS systems consistently receiving higher ratings of fit and comfort compared to CTS (p < 0.05). Perceived fit and comfort were strongly associated, and both significantly predicted overall acceptability (p < 0.001), with comfort emerging as the primary determinant. In contrast, total system weight was not a significant predictor of fit or comfort (p > 0.05) and demonstrated a small negative association with overall acceptability. These findings establish a subjective baseline of perceived fit under standardized conditions and highlight the role of comfort in equipment acceptability. Optimizing comfort and body–equipment interaction appears more critical to acceptability than reducing system weight alone. This work provides a foundation for future research integrating subjective and objective approaches to support the development of more effective and acceptable LCSs.

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