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Quantifying agglutination process under different analyte concentration using a hybrid convolutional neural network and comparative deep learning models
No full textThe full abstract for this thesis is available in the body of the thesis, and will be available when the embargo expires.Applied Science, Faculty ofEngineering, School of (Okanagan)Graduat
From biowaste to biomedicine : antimicrobial and biocompatible cellulose aerogels derived from agricultural residues
No full textThe full abstract for this thesis is available in the body of the thesis, and will be available when the embargo expires.Applied Science, Faculty ofEngineering, School of (Okanagan)Graduat
Characterization of Coxsackievirus B3 3C protease cleavage of the RelA-associated inhibitor
No full textViruses have a limited coding capacity and therefore rely on hijacking host cellular machinery to facilitate infection. To achieve this, RNA viruses encode proteases that are involved in both viral polyprotein processing and the cleavage of host proteins. These cleavage events modulate cellular processes and evade innate antiviral defenses to promote replication and infection. Coxsackievirus B3 (CVB3) is a positive-sense single-stranded RNA virus that, like other picornaviruses, encode the 2A and 3C proteases (3Cpro). Recent advances in proteomics, such as terminal amine isotopic labeling of substrates (TAILS), have enabled the identification of hundreds of novel host proteins cleaved under viral infection. Among the host proteins identified by TAILS as potential CVB3 3Cpro targets, the RelA-associated inhibitor (RAI) was previously confirmed to be cleaved during infection, though the functional effects of cleavage remain unknown. In this thesis, I screened several proteins for cleavage under CVB3 infection and followed up on characterizing RAI cleavage and its functional outcomes. I confirmed that RAI is targeted by CVB3 3Cpro at the TAILS-predicted target site Q168↓G169. Therefore, cleavage of RAI at these sites generates at least two novel truncated fragments. It has been shown that protein fragments generated by viral protease cleavage can acquire novel functions to facilitate virus infection. Here, I found that overexpression of the N-terminal fragment generated by cleavage at Q168↓G169 inhibits NF-κB to a greater extent than the full-length protein. Furthermore, overexpression of this fragment also enhanced viral yield in host cells without affecting viral RNA replication. Together, these findings reveal a novel mechanism by which CVB3 modulates host immune signaling through 3Cpro-mediated cleavage of RAI. Understanding how viral proteases manipulate host substrates provides critical insight into virus-host interactions and can inform the development of antiviral strategies targeting protease activity or their host protein substrates.Medicine, Faculty ofBiochemistry and Molecular Biology, Department ofGraduat
Smooth muscle cell lysosomal acid lipase in atherosclerosis
No full textBackground: Atherosclerosis, in the form of ischemic heart disease and stroke, is the leading cause of death globally. Its pathogenesis involves lipid accumulation in artery wall foam cells. Previous work indicates that foam cells in human and mouse atherosclerotic lesions are predominantly derived from smooth muscle cells (SMCs). Our laboratory has also characterized SMCs as being low in lysosomal acid lipase (LAL), the sole lysosomal cholesteryl ester hydrolase. Cholesteryl ester hydrolysis is critical in releasing cellular cholesterol stores for removal via cholesterol efflux. SMCs therefore represent a resistant pool of foam cells with reduced ability to efflux cholesterol. My dissertation investigates whether increasing LAL in SMCs can increase efflux for therapeutic effect in atherosclerosis.
Methods and Results: In Chapter 1, I provided an overview of atherosclerosis, SMCs, and LAL.
In Chapter 2, I tested whether increasing LAL activity in SMCs in vitro reduces lysosomal cholesteryl ester accumulation and increases cholesterol efflux, using adenoviral vectors, lipid nanoparticles (LNPs), and conditioned medium from SMCs treated with LNPs carrying LIPA mRNA, which encodes LAL. Increasing LAL activity by these methods reduced lysosomal cholesteryl esters. Treating SMCs with LNP LIPA conditioned medium increased efflux to ApoAI.
In Chapter 3, I utilized a mouse model containing a tetracycline-response element promoter controlling human LIPA and a SMC specific promoter (SM22alpha) controlling a reverse-tetracycline transactivator, on a background of ApoE-deficiency, to specifically overexpress LAL in SMCs in response to doxycycline. I confirmed with preliminary data that increased SMC LAL reduced atherosclerosis progression.
In Chapter 4, I tested whether increased circulating LAL stimulates atherosclerosis regression. LNPs carrying LIPA mRNA were injected into ApoE-deficient and AAV-PCSK9 atherosclerotic mice. I demonstrated increased serum LAL activity and aortic LAL protein, and preliminary evidence of reduced atherosclerosis, but also excess mortality in ApoE-deficient mice with prolonged LNP treatment.
Conclusions: Increasing LAL in SMCs reduces lysosomal cholesteryl esters, freeing cholesterol stores to be effluxed from the cell. I determined that this reduces atherosclerotic lesion area in my SMC-specific LAL overexpression model. I also investigated LNP-mRNA as a method to increase LAL and target SMCs. These studies validate LAL and SMC foam cells as crucial therapeutic foci for atherosclerosis.Medicine, Faculty ofMedicine, Department ofGraduat
Transformative frameworks and strategic planning for wildlife stewardship, co-management, and Indigenous-led conservation
No full textWildlife management and conservation is a complex and dynamic undertaking, extending beyond ecological considerations to encompass human— including social, economic, political, and cultural— dimensions. Within Canada, wildlife management and conservation are increasingly contested. Species declines and ecosystem degradation point to deficiencies in the status quo approach. Parallelling the ecological implications of species declines and ecosystem degradation is the threat to the food sovereignty, ways of life, and wellbeing of Indigenous Peoples. The necessity for improving wildlife management and conservation is well-recognized. Empowering the governance, stewardship, and knowledge systems of Indigenous Peoples offers a pathway to improve both ecological and social outcomes.
Situated between species decline, ecosystem degradation, and Indigenous reconciliation and resurgence, this research highlights contemporary challenges and opportunities for wildlife management and conservation in Canada, with an emphasis on British Columbia. The objectives were to a) synthesize the state of Indigenous governance, stewardship, and knowledge within the Canadian wildlife management context, b) examine the process, strengths, and challenges for Indigenous-led conservation planning, and c) describe options for empowering Indigenous governance, stewardship, and knowledge through wildlife management. These objectives were achieved through the development of British Columbia-based case studies that evaluate the reconciliation-based conservation paradigm; systematic review of Canada-based co-management studies to study the role of Indigenous knowledge systems in wildlife management decision-making and practice; and participatory research that supported Xeni Gwet’in First Nation Government in the development of their wildlife management strategy.
A foundational component of this research was the collaborative approach with Xeni Gwet’in First Nation Government, that included both applied and academic contributions. The applied contribution was the development of a wildlife management strategy for the direct use and utility of Xeni Gwet’in First Nation Government. The academic contribution was a case study documenting the Xeni Gwet’in wildlife management strategy planning process.
This research offers frameworks, operational models and grounded case studies. The results present core requirements for reconciliation-based conservation to meaningfully occur, a model for mobilizing Indigenous Knowledge Systems throughout the wildlife management process, and a strategic planning approach and adaptive tools in support of Indigenous-led conservation. Together, the findings highlight opportunities for and barriers to change in contemporary wildlife management and conservation systems.Science, Irving K. Barber Faculty of (Okanagan)Graduat
The extractive fold : divergent paths in computational origami
No full textThis thesis examines the transformation of origami from a traditional craft into a highly mathematized and computational art form in the late twentieth and early twenty-first centuries. It argues that this evolution has produced a central tension: a divergence between origami as a practice of abstract mathematical exploration and origami as one rooted in the material specificity of folded paper. This tension is analyzed through the influential curatorial framework of The Museum of Modern Art (MoMA), particularly its 2008 exhibition, Design and the Elastic Mind. This thesis contends that MoMA’s technocentric and “elastic” framework promoted an extractive view of origami, valuing it primarily for its ability to yield transferable mathematical principles for scientific and engineering applications. This argument is developed through two case studies. The first, the curved-crease sculptures of Erik and Martin Demaine, exemplifies the practice championed by MoMA, where paper serves as a “passive material” for mathematical discovery. The second, the work of physicist and artist Robert J. Lang, presents a contrasting approach that maintains a dual centrality between the computational crease pattern and the final, material art object. By analyzing the reception of these artists at MoMA, the thesis reveals how institutional framing can privilege a deconstructed, utilitarian vision of a craft, while sidelining practices that remain committed to the inseparable bond between form, material, and the art of the fold itself.Arts, Faculty ofArt History, Visual Art and Theory, Department ofGraduat
Disposing the displaced : the violent governance of waste and recycling in Istanbul
No full textA familiar sight on the streets of Istanbul is that of informal recycling workers pulling heavy carts filled with waste. For decades, waste collection has served as a vital lifeline for marginalized groups such as internally displaced Kurds, Roma communities, and noncitizens, who are systematically excluded from formal employment due to entrenched racial discrimination. Despite their indispensable role as the backbone of urban waste infrastructures, these workers are increasingly subjected to violence through prohibition, aggressive policing, and restrictive environmental policies.
This dissertation draws on 15 months of ethnographic fieldwork conducted in Istanbul between 2022 and 2025 to examine how state interventions into informal recycling businesses institutionalize violence as a core logic of urban waste governance in Turkey, consolidating authoritarian control over everyday life. I analyze how violent border regimes intersect with Istanbul’s informal recycling sector by examining the distinct language of waste infrastructures and showing how displaced populations are rendered disposable through dehumanizing state violence. I describe how mass deportations of Afghan migrants have disrupted Istanbul’s waste economies and how these disruptions are further intensified by major disasters such as the COVID-19 pandemic and the February 6th earthquakes. Exploring how recyclers navigate uncertainties during times of compounding crises, I highlight the many failures of Turkey’s disaster governance. This research also interrogates the entangled stigmatization of waste work and drug use—both typically perceived as “dirty”—and documents how drug prohibition policies in Turkey legitimize violent interventions into recycling businesses.
Finally, exploring both collective and noncollective forms of resistance against systemic oppression, I illuminate the fragmented and asymmetric structure of the organized recycler movement in Turkey. I address the spatiotemporal constraints that inhibit sustained collective action, as well as the national, gendered, and ethnic inequalities that shape autonomous recyclers’ access to labour organizations. I emphasize how workers strategically challenge the power of Turkish nation-state and its bordering practices, asserting their right to collect waste and demanding recognition for their essential labour. Taken together, my ethnography contributes to a range of scholarly conversations, including linguistic anthropology, migration and mobility studies, disaster research, the anthropology of drugs, and social movement studies.Arts, Faculty ofAnthropology, Department ofGraduat
Development of sustainable cement composites : understanding the effect of cellulosic additives and waste biomass
No full textFiber reinforced cement is widely used in non-structural building applications due to its improved toughness, strength, and durability. However, continued reliance on ordinary Portland cement and synthetic chemical additives raises concerns regarding environmental impact and long-term sustainability. This thesis addresses these challenges through two strategies: first, replacing petrochemical or silica-based additives with nano- to micro-scale cellulosic biomaterials, and second, reducing ordinary Portland cement use by partially substituting it with processed waste biomass and by developing a cement-free hybrid geopolymer binder.
In the first approach, nano- and micro-scale cellulosic additives were investigated in fiber cement reinforced with softwood kraft pulp. Among the nanocellulosic materials, cellulose nanocrystals at optimal concentrations (2–4 wt.%) produced notable improvements in workability, early hydration, and flexural strength compared to systems containing conventional chemical additives. These improvements were attributed to the high surface area and network-forming morphology of cellulose nanocrystals, which enhanced water transport, supported early hydration reactions, and promoted matrix densification. Micro-scale cellulosic additives also provided distinct benefits: alpha cellulose improved post-cracking toughness and workability by reducing yield stress, while microcrystalline cellulose enhanced peak flexural strength. Despite differences in absolute strength, the strength-to-weight ratios of systems modified with alpha cellulose and microcrystalline cellulose were comparable, suggesting that low-cost alpha cellulose can deliver similar performance benefits.
In the second approach, biochar derived from woody biomass was used to partially replace Portland cement. At an optimal dosage of 8 wt.%, biochar improved rheology, time-dependent thixotropy, and mechanical strength while reducing global warming potential by 18 % relative to a pure cementitious system. These effects were linked to its porous morphology and reactive surface, which enhanced water retention and hydration. Furthermore, a cement-free geopolymer binder composed of metakaolin and biochar was developed through mechanochemical processing and reinforced with pulp fibers, achieving flexural strengths of 13–15 MPa with substantially lower embodied carbon, demonstrating a viable route toward sustainable, high-performance fiber cement.Applied Science, Faculty ofChemical and Biological Engineering, Department ofGraduat
Structural and biochemical characterization of HOXB13 a prostate-specific transcription factor
No full textThe full abstract for this thesis is available in the body of the thesis, and will be available when the embargo expires.Medicine, Faculty ofMedicine, Department ofGraduat
Quantifying diegesis in situated visualization
No full textThere is a fundamental connection between the data we collect and the physical spaces from which it originates. As new technologies have emerged to allow spatial tracking and augmented reality visualization, researchers have increasingly explored ways to define this connection to support intuitive user interfaces and situated data visualization. The central goal of Situated Visualization (SV) is to integrate digital information into its relevant physical context seamlessly. While several frameworks have described aspects of this integration, they remain loosely defined, disconnected, and often fall short of evaluating its quality, specifically, the extent to which a visualization feels like a natural part of the environment rather than a superimposed artifact. To address this gap, this thesis introduces diegesis, a concept from storytelling disciplines that measures an element’s perceived belonging within a world, as a new theoretical lens for SV. This work is the first to formalize diegesis for this domain comprehensively. Through a systematic review of 50 recent works, this thesis introduces the SCORE framework, which quantifies diegesis through five measurable dimensions: Spatial proximity, Concreteness, cOherence, Referential context, and Environmental context. In addition to supporting qualitative comparison of existing designs, the framework provides a quantitative measure of diegesis, enabling SCORE to differentiate visualizations that prior models have treated as equivalent. Building on this, I applied SCORE to a corpus of 67 visualizations, enabling a cluster analysis that revealed five distinct design archetypes and offering a new taxonomy for comparing SV designs and articulating their inherent trade-offs. Finally, a systematic meta-analysis confirms the framework’s practical relevance by demonstrating that higher SCORE values are consistently correlated with favorable usability outcomes. Overall, this thesis provides the SV community with a new theoretical lens, a validated analytical tool, and actionable, evidence-based insights for designing visualizations based on their diegetic profile.Science, Irving K. Barber Faculty of (Okanagan)Computer Science, Mathematics, Physics and Statistics, Department of (Okanagan)Graduat