Electronic Theses and Dissertations (ETD)

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All theses from 2011 to the present are in this collection, as well as some from 2010 and earlier years.

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Everything is connected: Tracing multiple impacts to seafood access and adaptation assets in Skidegate, Haida Nation
(2026) Faralhi Daolio, Marcela; Singh, Gerald
For thousands of years, coastal Indigenous communities like the Haida Nation have relied on community-led strategies to adapt to environmental changes. Today, however, the cumulative pressures of climate change and anthropogenic activities are rapidly transforming the ecosystems that sustain Haida food systems and way of life. In response, the Haida community of Skidegate has developed adaptation strategies that provide meaningful opportunities, particularly for food independence and security. This research aims to understand Haida perspectives and experiences with social-ecological systems under threat from cumulative impacts across four main ancestral harvesting areas by creating qualitative models of pathways of effects (PoE). It also explores how the community has been responding to these changes by co-developing adaptation plans to clarify the links among locally relevant and effective adaptation strategies. We used an interdisciplinary approach that included a literature review, semi-structured interviews, workshops, and community gatherings. This work also adopts an asset-based perspective, focusing on community strengths and the factors that enable communities to develop adaptive strategies aligned with their values, Traditional Laws, and priorities. The results demonstrates that access to seafood for the Haida’s involves factors beyond those discussed in Western food security literature. As a result, a framework was created based on the perceptions of Skidegate participants to describe these factors. All the harvesting areas examined were described as influenced by multiple interconnected factors. Most pathways of effects identified drivers such as climate change, commercial fishing, habitat loss, and the decline of traditional practices. Specific areas faced unique stressors impacting different aspects of accessibility, although many drivers of change were common across all regions studied. Our findings indicate that deficit-based models can restrict options and foster dependence on external organizations. Results also demonstrate that the Skidegate community responds to environmental and social changes through ongoing food programs that combine harvesting, sharing, teaching, and community coordination, rooted in Haida values. These efforts are based on local knowledge and relationships rather than external adaptation frameworks. Participants described adaptation as an everyday practice involving collective decisions and actions (e.g., supporting harvesters, maintaining access to harvesting sites, and preserving cultural practices essential for harvesting). Therefore, the most effective opportunities to bolster future adaptation efforts lie in strengthening current strategies rather than developing new ones. The research process highlighted the importance of bottom-up approaches that actively involve community members in interpretation and analysis. This research promotes broad community support and expands the range of adaptation strategies by prioritizing Indigenous-led solutions and integrating reconciliation and Indigenous Knowledge. Ultimately, it underscores the vital role of community-driven efforts in addressing environmental challenges caused by cumulative impacts.
Microfluidic fabrication of enteric-coated liquid-core ATPS capsules for colon-targeted probiotic delivery
(2026) Yazdani Motlagh, Kaveh; Hoorfar, Mina
Colon-targeted delivery of live probiotics remains challenging because gastric acidity and intestinal bile salts can severely reduce viability, while premature leakage can prevent sufficient dosing at the site of action. This dissertation presents a simplified microfluidic platform for producing enteric-coated, liquid-core, hydrogel-shell capsules for colon delivery. The system generates water-in-water-in-oil (W/W/O) double emulsions using a poly(ethylene glycol) (PEG) and dextran aqueous two-phase system (ATPS) in a flow-focusing device, with improved droplet stability enabled by increasing channel height at the oil junction and avoiding complex surface treatments. The capsule architecture integrates (i) a PEG-based liquid core for high cargo loading, (ii) a dextran/alginate/Ca–ethylenediaminetetraacetic acid (EDTA) shell that is crosslinked on-chip via acid-triggered Ca²⁺ release, and (iii) a layer-by-layer coating of chitosan and Eudragit S100 nanoparticles to provide upper-GI protection and pH-responsive gating. To generate Eudragit S100 nanoparticles, a dedicated microfluidic micromixer was designed for continuous antisolvent nanoprecipitation (acetone→water), enabling rapid, reproducible mixing and supporting uniform enteric coating of the capsules. To explain and control emulsion morphology, we combined volume-of-fluid computational fluid dynamics (CFD) simulations with targeted experiments to quantify necking dynamics and internal recirculation patterns, revealing how shell viscosity and geometric confinement drive the formation of one-core or two-core morphologies. Capsule performance was evaluated under sequential exposure to simulated gastric fluid (SGF, 0–2 h) and simulated intestinal fluid (SIF, 2–6 h). Uncoated capsules showed poor gastric protection, with Escherichia coli Nissle 1917 (EcN) viability decreasing to 62% after 1 h and reaching 0% by 2 h in SGF. In contrast, chitosan-coated capsules maintained high SGF viability (93% at 1 h; 89% at 2 h), while the Eudragit+chitosan multilayer achieved the highest survival (97% at 1 h; 95.2% at 2 h). After transfer to SIF, both coated formulations remained highly protective, with the Eudragit+chitosan capsules sustaining a consistent ~5.9–6.1 percentage-point advantage over chitosan alone from 2–6 h (95.2→93.0% vs 89→87.1%). Functional assays demonstrated strong retention during simulated upper-GI transit, with negligible release in SGF (0–2 h) and low cumulative release (6.7%) after sequential SGF→SIF exposure (0–6 h). Under colon-mimicking conditions with simulated colonic fluid (SCF) containing dextranase, release followed a lag–acceleration–plateau behavior, reaching ~85–90% by ~3–6 h and ~95–100% by ~7–8 h, consistent with enteric dissolution and enzyme-driven shell loosening.
Navigating the meaning of body image among adults with breast cancer: A photovoice exploration
(2026) Remin, Shauna; Kwon, Jae-Yung; Newton, Lorelei
Substantial literature exists regarding breast cancer and body image; however, the bulk of existing research focuses on quantitative methods that often reflect a narrow, pre-defined definition of body-image. Such approaches may inauspiciously fail to capture the nuanced complexity in which individuals with breast cancer experience and interpret changes to their bodies. Qualitative approaches, which hold the possibility to provide richer, more contextual insights into the lived experiences of people with breast cancer, remain underutilized. Through semi-structured interviews, I explored contextual variables contributing to the meaning of body image among adults with breast cancer. Data were analyzed using thematic analysis. Four themes concerned with making meaning of body image were perceptions of self, psychological experiences, emotional conceptualizations and the impact of Photovoice on the participants’ journey. Findings highlighted the centrality of body image to breast cancer experiences and revealed how these concerns can remain overlooked. Implications for researchers and healthcare providers are discussed. This study highlights the power of collaboration through meaningful engagement with Patient Partners and identifies opportunities to foster more responsive oncology care practices aimed at improving the body image experiences of individuals living with breast cancer.
Topology-graded structures: Exploring heterogeneous architected materials for load bearing mechanics
(2026) Choi, Chiara; Yu, Bosco; Giles, Joshua W.
Heterogeneous architected materials (HAMs) are cellular structures whose topology, geometry, or density varies spatially. They represent an emerging frontier in materials engineering, offering property combinations inaccessible to both conventional monolithic solids and homogeneous lattice architectures. Enabled by advances in additive manufacturing, HAMs can be deliberately engineered to produce locally tailored stiffness, strength, energy absorption, and permeability across a single monolithic component. Despite rapid progress, the structure–property relationships of complex heterogeneous networks remain incompletely understood, and a fundamental gap exists between idealized lattice studies and the design of load-bearing components that exploit spatial heterogeneity as a functional design variable. This thesis addresses this gap through two complementary studies, treating heterogeneous architected materials first as materials, then as elements of an engineered system. The first study investigates the compressive mechanics of additively manufactured hexagonal meta-materials incorporating 5-7 defect arrangements inspired by graphene grain boundary geometries. Three specimen sets, bidomain meta-crystals ("bi"), polydomain meta-crystals ("poly"), tilted meta-crystal ("tilted"), were fabricated via selective laser sintering in Nylon PA2200 across eight misorientation angles ranging from 0° to 30°. Quasi-static in-plane compression experiments and finite element simulations were used to characterize apparent compression modulus, peak stress, densification strain, and energy absorption. Results suggest that by varying the misorientation angle of a pure and 5-7 defect hexagonal system a dependency is observed for the strength of the structure, in contrast to energy absorption and stiffness, which exhibit an isotropic response independent of misorientation angle. The introduction of 5-7 defects in a stacking configuration impedes shear band propagation and promotes localized normal deformation, elevating peak stresses, while staggering configurations encourage controlled intersecting shear bands producing characteristic shear collapse. A key finding is that Hall-Petch-like strengthening in polydomain meta-crystals is not unilateral: the stacking configuration yields a Hall-Petch-like relationship with decreasing domain size, while the staggering configuration produces an inverse relationship, establishing misorientation angle as a factor in determining which strengthening regime applies. Experimental and finite element results for bidomain meta-crystal specimens are in general agreement in trend and magnitude; scatter in experimental data is attributed to process-induced factors inherent to selective laser sintering, such as thermal shrinkage and retained powder, which introduce variability not fully captured by the simulation model. Building on these mechanistic insights, the second study introduces a novel simple cubic–face-centered cubic (SC-FCC) unit cell topologically graded design for load-bearing hip implants. A crystallographic-based design method employing symmetry-parameter coordinates was adapted to mathematically describe and fabricate intermediate architectures spanning the SC-to-FCC transition. Two design groups were developed: a uniform group with constant strut thickness to isolate geometric effects, and a tailored group with varying strut thickness tuned to replicate the stiffness of cortical bone (10–30 GPa). Specimens were fabricated via stereolithography for compression and bending characterization, and via selective laser sintering in C300 maraging steel for implant-level testing. Quasi-static compression experiments confirmed that the tailored group produces a linear progression in apparent compression modulus and peak stress across the SC-FCC transition, while the uniform group exhibits a parabolic profile. Four-point bending tests demonstrated that longer SC-FCC transition zones achieve the highest bending modulus and maximum stress, outperforming abrupt step-change configurations. Implant performance was evaluated using a digital image correlation system on specimens embedded in bone-mimicking foam and loaded to 2300 N. All implant variants produced average foam strains within Frost's Mechanostat ideal remodeling range of 1500–3000 με, and interfacial micromotion remained below the 30 με threshold which has been documented to impact osseointegration across all measurement locations. Pore sizes of 100–2600 μm and bulk porosities of 46–60% confirmed compatibility with both vascularization and bone ingrowth requirements. Collectively, this work establishes that deliberate spatial heterogeneity in unit cell topology, whether through grain-boundary-inspired defect engineering or through continuous SC-FCC grading, provides independent control over mechanical performance that relative density variation alone cannot achieve. The findings advance the mechanistic understanding of heterogeneous architected materials and demonstrate a viable, experimentally validated pathway for their deployment in next-generation additively manufactured load-bearing applications.
Weaving currere: Possibilities, provocations, and performative inquiry in drama education
(2026) Shenfield, Robyn; McDonough, Graham
The aesthetic space of the drama classroom can serve as a locus of hope, transformative action, and “complicated conversation” (Pinar, 2019), where students may explore identities, roles, and responses to social challenges through critically engaged drama pedagogy. This dissertation presents a compilation of eight papers examining diverse inquiries in drama education. Framed by three interwoven “red threads” (Fox & Dauber, 1999), I locate my scholarly practice within a/r/tography (Irwin, 2013; Irwin & de Cosson, 2004) and situate my work as an enactment of currere (Pinar, 1975) within curriculum studies. The first red thread, Possibilities, explores emerging and hopeful futures for drama education. It includes critical reflections on the development of a new performance studies curriculum, and a small-scale interview study examining how experienced drama teachers respond to this newly developed curriculum. The second thread, Provocations, interrogates pedagogical practices in drama education, highlighting tensions, considerations, and wonderings. I argue that drama education may pedagogically trouble didactic moral instruction and offer space for the exploration of morally ambiguous dilemmas. I position drama and theatre for young people as rich pedagogy in which to explore philosophical problems with young people, and also discuss the importance of deepening awareness of potential harms that may arise even from well-intentioned practices. The final thread, Performative Inquiry, employs arts-based methodologies, including poetic inquiry and ethnodrama. Here I discuss engagement with poetic inquiry during qualitative research, an autoethnographic play text, and an ethnodrama exploring young people’s responses to representations of mental health topics in Theatre for Young Audiences plays.
Cognitive fatigue assessment using electroencephalography
(2026) Gill, Gregory W.; Krigolson, Olav
Cognitive fatigue, a state commonly experienced during prolonged tasks, is a major contributor in human response inaccuracies and impaired performance, implicating cognitive state as a leading cause of accidents, injuries, and other errors in the workplace. In this thesis, I sought to illustrate that the P300, a widely investigated event-related potential component in EEG literature and purported to be an indicator of cognitive fatigue levels in humans, can be elicited in participants while they performed under an attentionally demanding task. I hypothesized that we would see an oddball effect displayed in the covert task given to participants despite not being directed to attend to it. This would allow me to utilize this effect in real-world situations. Indeed, an oddball was detected, providing evidence that a P300 can in fact be generated without the need of using specifically attended stimuli, which can be utilized in future research as a reliable measure of fatigue when used in real-world situations such as in high sensitivity careers like long-haul truck drivers, pilots, and occupations of that nature.
Mergers, black holes, and the end of star formation: a simulation-boosted multi-wavelength approach to understanding galaxy quenching
(2026) Wilkinson, Scott J.; Ellison, Sara L.; Brown, Toby
Over cosmic time, galaxies are transitioning from star-forming to quiescent in a process known as quenching. Star formation will necessarily halt if there is no molecular gas available to fuel star formation, or if molecular gas is present but unable to form stars. Although there are many proposed galaxy-scale events that can lead to the end of star formation in galaxies, this work focuses primarily on the role of galaxy mergers and the energetic feedback processes from active galactic nuclei (AGN) and their affect on the molecular gas in galaxies. Surveys of galaxies observed in both optical (for observing the stellar component) and millimetre wavelengths (for observing the molecular gas component) allow for the exchange between gas and stars to be studied. In the existing surveys of galaxies observed in optical and millimetre, there is a trade-off between the resolution of the observations and the sample size of the survey. In this work, I create a dataset that strikes a balance between large but unresolved surveys and the higher resolution surveys with smaller samples. In a significant technical undertaking, I combine archival products from the Sloan Digital Sky Survey (SDSS) and the Atacama Large Millimetre Array (ALMA) to create a "semi-resolved" survey of 277 galaxies, meaning the inner and outer regions of each galaxy are independently resolved. I call this dataset the SDSS-ALMA Legacy Value Archival Gas Exploration (SALVAGE). I use SALVAGE to better understand global scaling relations, such as the star forming main sequence (SFMS). On the SFMS, I find that the global star formation rate (SFR) of a galaxy is driven largely by the star formation efficiency of the inner region. Meanwhile, above and below the SFMS, I find that the global SFR of a galaxy is driven more by the availability of gas in its inner region, even more so than its global gas reservoir. My results distinguish the central few kiloparsecs as the most consequential region for galaxy evolution at low redshift, likely due to the role of both mergers and AGN in driving gas inwards and either ejecting or consuming molecular gas from the inner regions. Although theory suggests that AGN feedback can eject gas from the central region of a galaxy, previous studies of the global molecular gas reservoirs of AGN hosts have concluded that they are not systematically depleted. I use SALVAGE to select 70 AGN and test if they have depleted molecular gas in the central ~1-2 kpc. Using several multiwavelength definitions of AGN and three metrics of gas depletion in comparison with a matched non-AGN control sample, I conclude that AGN do not have depleted gas in the central ~2 kpc. The lack of depletion could be a result of the resolution of the data or a temporal effect where AGN-driven gas depletion is only seen after the AGN is turned off. Indeed, many galaxies in SALVAGE are found to have centrally depleted molecular gas, but they are found in both the AGN and non-AGN samples. To explore the causes of depleted central molecular gas in galaxies, I select a sample of 28 central gas deficient galaxies (CGDs) from SALVAGE. I demonstrate that CGDs are examples of galaxies that are quenching inside-out, but that they are less likely to be AGN than matched controls. I use a cosmological simulation called IllustrisTNG50 to select an analogous sample of 70 CGDs, which allows me to "rewind the clock" of the simulation to see what caused the central gas to be removed. Tracing these galaxies back 0 to 8 Gyr in the past to the moment they became a CGD, I find that 78% are associated with the onset of kinetic mode AGN feedback, which is known to expel gas from the central regions. Galaxies with centrally depleted gas reservoirs are therefore likely caused by AGN feedback in the distant past, but I identify several tests that will be needed to confirm this result. Galaxy mergers can induce gas inflows leading to a starburst and ultimately halt star formation. Reliably identifying galaxy mergers in optical imaging can depend on the resolution and depth of the imaging as well as the method used to identify the mergers. No previous work has conducted a comprehensive assessment of the combined effect of all three of these variables on our ability to identify recent galaxy mergers. I select 424 known galaxy mergers (and 424 non-merger controls) from a cosmological simulation called IllustrisTNG100 and create synthetic optical images. I degrade each galaxy image to 36 different image qualities, in terms of their depth and resolution, spanning the range of present and forthcoming ground-based optical imaging surveys. I apply a suite of commonly-used merger identification methods and assess the completeness of recovered mergers. Even in perfect quality images, I find that most methods recover only 37-55% of mergers and I show that the completeness depends on image quality, galaxy properties, and the viewing angle of the observer. The values of completeness and false positive rate reported in this work can be used to account for the number of missed mergers in any ground-based imaging survey. Post-starburst galaxies (PSBs) are defined as having had a recent burst of star formation that has subsequently halted. PSBs are therefore an excellent probe of rapid quenching mechanisms and have long been associated with galaxy mergers. Recent works using resolved spectroscopy have expanded the classification of PSBs into central PSBs (cPSBs), where the quenching is centrally concentrated, and ring PSBs (rPSBs) where the quenching is occurring in a ring. Previous works that use only optical imaging have led to conflicting results regarding the local mechanism causing central quenching versus outer quenching in a ring and whether one can evolve into the other. I use a new survey called the Kiloparsec Investigation of Local Objects’ Gas And Star-formation (KILOGAS) to identify 12,096 PSB regions and study their molecular gas content. By comparing the molecular gas in PSB regions to typical star forming regions, I find that the local process that inhibits star formation depends on the galactocentric radius. Furthermore, by comparing the molecular gas profiles of cPSBs and rPSBs, I find that rPSBs with ongoing central star formation are consistent with evolving into centrally quenched PSB systems. This body of work demonstrates (1) the importance of combined optical and millimetre data for understanding galaxy evolution, (2) the latent ability of archival data for assembling large and diverse datasets, (3) the relevance of the central few kiloparsecs for the evolution of galaxies as a whole, and (4) the utility of cosmological simulations for interpreting observational results.
Verified commitment schemes and reduction proofs in the lean proof assistant
(2026) Blacquiere, Ashley; Kapron, Bruce
This thesis presents a formalization of commitment schemes in the Lean 4 theorem prover, together with machine-checked proofs of their core security properties. Commitment schemes allow a party to commit to a value while keeping it hidden, with guarantees of binding (the value cannot be changed) and hiding (the value remains secret until revealed). We develop a general, specification-driven framework for modelling commitment schemes and their security definitions in Lean, using a probabilistic monad to express adversarial games and reduction-based proofs. Within this framework, we formalize two canonical schemes: the Pedersen commitment scheme and the ElGamal commitment scheme. For Pedersen, we prove perfect hiding and computational binding via reduction to the discrete logarithm problem; for ElGamal, we prove perfect binding and computational hiding via reduction to the decisional Diﬀie–Hellman assumption. This work contributes both concrete formalizations and reusable abstractions for cryptographic reasoning in Lean, advancing the emerging area of mechanized cryptography within the system.
Black holes immersed in a magnetic field: the case of the Ernst-Wild geometry
(2026) Taylor, Kate; Ritz, Adam
This thesis explores how magnetic fields surrounding black holes influence the signals we observe from them - both in gravitational waves and in direct images. Although most theoretical models treat black holes as isolated objects in vacuum, real astrophysical black holes can exist in magnetized environments. These magnetic fields can subtly alter the behaviour of light and gravitational waves near the black hole and therefore affect what our detectors and telescopes record. The first part of the thesis focuses on the visual signature of magnetized black holes - their photon rings and shadows - using numerical backwards ray tracing. It was found that rotation and magnetic fields act in competing ways, one flattening and the other stretching the observed shadow, and that these effects are directly connected to the same oscillation modes that govern gravitational wave ringdown. The second part of the thesis studies how a magnetic field modifies the vibrations of a rotating black hole following a binary black hole merger. Using analytical expansions and numerical techniques, I calculated how the characteristic oscillation frequencies change in the presence of a weak magnetic field and tested these effects within the LIGO-Virgo-KAGRA ringdown analysis pipeline pyRing. This provides the first quantitative estimate of how surrounding magnetospheres could bias the measurement of black hole mass and spin from gravitational wave data. Together, these results link two powerful observational windows - gravitational waves and black hole imaging - within a single theoretical framework that accounts for magnetized environments.
Archiving the past, present, and future: Creating a uniquely huuʕiiʔatḥ archival framework
(2026) Wilton, Emma A.; Walsh, Andrea N.; Happynook, Tommy
This thesis explores ways in which huuʕiiʔatḥ cultural knowledges are central to the creation of a physical archive of huuʕiiʔatḥ cultural Belongings, thus providing an alternative to a traditional colonial archival framework where often huuʕiiʔatḥ cultural Belongings are categorized in non-Indigenous contexts. The Huu-ay-aht First Nations identified the need for a culturally specific archive to record and store cultural knowledge gathered during the negotiations of the Maa-nulth Final Agreement. I was invited by huuʕiiʔatḥ hereditary chief ḥapinyuuk Dr. Tommy Happynook on behalf of his community, to work on developing a culturally specific archive for the Huu-ay-aht First Nations. I developed a research methodology framed by three phases: Showing Up, Listening, and Reflecting. The development of this methodology was prompted by my engagement in community-led discussions with the ḥaẃiiḥ and nananiiqsu Councils. Through my community discussions, a framework featuring huuʕiiʔatḥ hereditary houses as the main organizing structure with layers for maatmaas (House), family, individual, and ʔiiḥmisʔap (Belongings) emerged. Information held in these “layers” of the archive ensure culturally safe access to Belongings and knowledges, and promotes the transmission of cultural knowledges amongst generations. As a case study, this thesis serves as a point of departure for consideration by Indigenous Nations and researchers seeking to create a culturally specific archival framework. Woven throughout the pages are my honest retellings and reflections of events as a non-Indigenous anthropologist. I argue I cannot remove myself from this research as it is my subjectivities and lived experiences which have brought me to this point in time to conduct this research. Relationality is core to how I conducted this research and the archival framework itself. I reflect on my research relationships, my understanding of Witnessing, and what I have gained from this research into my professional career.
Specification-driven generation of type-safe python configuration classes for JSON inputs
(2026) Gilanilarimi, Mohsen; Schneider, Teseo
Modern scientific and engineering libraries often use JSON configuration files to run simulations and workflows. JSON is readable and widely supported, but real configuration files can be hard to write correctly because they may have deep nesting, lists, optional and required fields, fixed choices, and numeric limits. In many libraries, these rules are described in a separate input specification file, but developers usually create the type-safe interface and validation code by hand. This can repeat the same logic, become inconsistent when the specification changes, and lead to unclear error messages. This thesis introduces a system that takes the JSON input specification as the main reference and automatically generates strongly typed Python configuration classes from it. The generated classes are organized in the same structure as the specification using nested classes, and users can set values with normal attribute access to ensure each value is placed in the correct part of the specification. Validation is built into both the constructors and the property setters. This means whenever a value is given, the system checks its type and rules (for example, valid ranges, allowed options, or required file extensions). It also allows complex parts of the configuration to be filled step by step by setting their child properties. The system shows which fields are required using the generated documentation, and it also provides a report method that finds any missing required values before saving. After the configuration is complete, the objects are converted back into JSON-compatible output that matches the specification by design and can be used by other libraries. Internally, the approach builds an intermediate tree from specification pointers and then generates the class from it. It supports heterogeneous lists with wildcard routing and polymorphic variables with multiple allowable shapes. Robustness is tested by making controlled changes to the specification and running failure-case tests. The results show that the system reliably works with realistic patterns and clearly detects unsupported types and problems when the specification hierarchy is in the wrong order.
Using microchemistry to track the marine migrations of coho and Chinook salmon
(2026) Quindazzi, Micah; Juanes, Francis
Pacific salmon (genus Oncorhynchus) display complex life history strategies from estuary entry to their return migrations. During this marine migration and residency period, Pacific salmon can traverse thousands of kilometers, moving to and through multiple unique marine regions with their own unique set of environmental and ecological conditions that these fish must contend with to survive. The marine migration and residency period of Pacific salmon, is still poorly described, often considered a black box, despite 100 years of considerable international effort. Current methods using passive tags are often difficult to interpret through seasons and across patchy distributions and inconsistent fishery efforts. Active tags can provide more high scale resolution, though at a steeper cost and substantial tag burden effects for smaller salmon. Intrinsic tags, those aspects of the fish that are universally part of an organism’s biology, provide researchers with a novel method of tracking fish migrations. This dissertation reports on the results of using otoliths as intrinsic tags in both coho (O. kisutch) and Chinook salmon (O. tshawytscha). Chapter 1 acts as an introduction and a 100-year retrospective on Pacific salmon tagging ventures up to this point in time. Chapter 2 and 3 focus on using otolith microchemistry to identify the marine migrations of coho and Chinook respectively. Chapter 4 identifies growth considerations within coho salmon related to migration, with slower growing coho in the early marine period being more likely to partake in further migrations. Chapter 5 focuses on producing otolith size to fork length size to interpret early life stage events in Chinook and coho salmon, with some investigations into the estimation of the size at estuary entry and estuary residence time of Chinook salmon. Chapter 6 looks at ageing Chinook salmon through otolith microchemistry, with some key findings including that older Chinook are more likely to be underaged by scales, and that larger Chinook salmon at their first ocean winter return at a younger age and smaller size. Chapter 7 applies otolith microchemistry analyses to contaminants research, identifying that predicted otolith marine migration life-history types match general expectations for contaminant profiles of Chinook salmon that conduct migrations to both coastal and offshore environments. Finally, chapter 8 is a six year retrospective on this type of research and some considerations for future international collaborations.
Design and optimization of an electric vehicle battery thermal management system using CFD simulations and CFD-derived GPR-ANN metamodels
(2026) Wong, Chon Him; Dong, Zuomin
Transportation is a major contributor to global greenhouse gas (GHG) emissions. Battery electric vehicles (BEVs) have gained widespread adoption in passenger car applications due to their high energy efficiency and potential to reduce carbon emissions. Extending BEV technology to medium-duty trucks (MDTs), which are widely used in commercial transportation, can further improve energy efficiency and reduce GHG emissions. The thermal management system (TMS) for the battery energy storage system (BESS), propulsion motors, and power electronics is essential to ensure safe, reliable, and efficient BEV operation while extending battery life. For electric medium-duty trucks (e-MDTs), which operate under diverse and demanding duty cycles, designing an effective TMS is particularly challenging due to the complex heat transfer processes within battery packs and their associated liquid-cooling and heating systems. High-fidelity computational fluid dynamics (CFD) simulations are typically required to evaluate and optimize BESS thermal management performance. However, such simulations are computationally intensive, making large-scale design exploration across varying operating conditions impractical. This work develops data-driven Gaussian Process Regression (GPR) and Artificial Neural Network (ANN) metamodels to approximate the thermal behaviour of BESS and enable efficient Battery Thermal Management System (BTMS) design optimization. A numerical BTMS model for an e-MDT is developed in MATLAB/Simulink, and CFD simulations are conducted for multiple battery pack and BTMS configurations under representative driving conditions. The resulting simulation data are used to train GPR-ANN metamodels that predict cooling performance without requiring repeated CFD simulations. The proposed framework reduces simulation time by approximately 97% while maintaining a maximum prediction error of 1% for the selected operating scenarios, providing an efficient and accurate approach for the model-based design and optimization of BTMS for e-MDTs.
Second-order nonlinear optics as an orientation-independent probe of molecular environments at interfaces
(2026) Kumarasiri, Aruna; Hore, Dennis Kumar
Interfacial chemistry is fundamentally governed by a unique molecular environment, within which the electronic structure changes drastically across distances of only the order of angstroms, yet it profoundly controls much of the macroscopic behaviour in materials science, catalysis, and biological systems. With such critical importance, the need for interface-specific analytical techniques has become increasingly apparent. As a result, nonlinear optical techniques, such as vibrational sum frequency generation (SFG), have become powerful tools for probing interfaces, particularly due to their inherent surface specificity. Even though these techniques show great promise for such applications, the electronic structure information that SFG provides is inherently coupled with the molecular orientational distribution of the molecules, such that, extracting structural information often has to be done under the assumption of a particular orientational distribution function. This, in return, introduces significant uncertainties into quantitative interfacial analysis that could potentially lead to inaccurate interpretations. In this dissertation, a theoretical and experimental framework is introduced for the SFG process to improve the accuracy of interfacial analysis by addressing this matter, to extract the electronic structure information at the interface without committing to any particular orientational distribution. The second chapter of the dissertation demonstrates a novel theoretical framework to determine the surface hyperpolarizability ratio—one of the most fundamental parameters in interfacial chemistry as it directly reflects the molecular electronic response at the interface—completely independent of, and therefore unaffected by, the orientational distribution of the molecules. In this way, the results of this work leverage the best features of the SFG technique, that is, its surface specificity, while expanding its practicality toward what is typically accessible only through bulk isotropic measurements. Another critical challenge to address in this type of work is experimental accuracy across the different polarization combinations of the SFG signal. To address this, building on our theoretical foundation, the third chapter of this dissertation introduces a null-angle-based calibration method for SFG analysis. This calibration procedure also helps extend this orientational distribution-free framework into buried interfaces. Finally, in the fourth chapter of the dissertation, the orientational characteristics across different interfaces were analyzed with the aid of the previously developed theoretical and experimental framework, and the importance of using surface-specific parameters for accurate orientational analysis was demonstrated, strengthening the use of polarization-resolved SFG as an accurate quantitative probe of interfaces.
Scaling the growth and characterization of perovskite single crystals for X-ray detection
(2026) Sandor, Nicholas; Saidaminov, Makhsud
Metal halide perovskite semiconductors are promising materials for direct-conversion radiation detection. However, their development faces challenges in growing sufficiently large crystals and rapidly characterizing detector arrays. Prior approaches to growth of large crystals have focused on chemical methods of controlling growth rates and nucleation, and most readout methods employ expensive integrated circuits with limited flexibility. A computer vision system was developed to track the growth of single crystals, providing insights into methods of growing large crystals and eliminating nucleation. Further, a readout system based on a precision switching topology was developed to allow for low cost, flexible evaluation of detectors. These two systems address key problems impeding the research of perovskite radiation detectors in the intermediate stage, allowing for improved growth processes and rapid evaluation of integrated detectors.
Searching the ḥaḥuułi: A site inventory of čaačaac̓iiʕas, on behalf of huuʕiiʔatḥ
(2026) Bailey, Hannah Lauren; Happynook, Tommy; McLaren, Duncan Stewart
čaačaac̓iiʕas (Carnation Creek) is located on the eastern shore of Barkley Sound, on the west coast of Vancouver Island, within huuʕiiʔatḥ (Huu-ay-aht) ḥaḥuułi (house/territory). čaačaac̓iiʕas is a watershed, and the site of an ongoing ecological experiment (Carnation Creek Watershed Experiment). Indigenous knowledge and ethnographic accounts reference human occupation in čaačaac̓iiʕas prior to European contact. I was invited to conduct an archaeological survey in čaačaac̓iiʕas by Dr. Tommy Happynook and the huuʕiiʔatḥ ḥaw̓iiḥ council (Hereditary Leaders council). This project builds on Dr. Happynook’s anthropological studies of the ḥaḥuułi and provides archaeological insight into past human land use and occupation at čaačaac̓iiʕas. Indigenous and archaeological research methodologies were employed to identify, record, and analyze one cultural shell deposit, one fish weir, two CMTs, two petroforms, one naturally occurring shell bearing matrix, a potential historic longhouse deposit, and several gardens. Archaeological evidence stands to add to current understandings of human activity in the area while also providing a historical record for čaačaac̓iiʕasʔatḥ and huuʕiiʔatḥ.
Contaminated sites on reserve: Federal law, policy and the transition to First Nations Land Management
(2026) James, Meredith; Curran, Deborah
In this thesis I undertake a comprehensive review of federal contaminated sites policy to examine the role of federal institutions in shaping the design and implementation of that policy on reserve. I adopt a historical institutional approach, beginning at the emergence of federal contaminated sites policy in the late 1980s and tracing its evolution to the present. I argue that the federal approach to contaminated sites is the product of a policy paradigm oriented around the federal government’s role as a “prudent landowner”. I also examine the interaction of federal contaminated sites policy with the Framework Agreement on First Nation Land Management. I argue that implementation of the environmental provisions of the Framework Agreement has been layered onto the existing federal contaminated sites regime. This has created misalignments that limit the scope of environmental self-government, particularly where First Nations’ expectations that contaminated sites will be remediated before the federal government transfers governance authority are not met. I explore how First Nations may use environmental law-making powers under the Framework Agreement to respond to these constraints. I propose that environmental laws enacted by First Nations offer a pathway to address some environmental harms and also contest the ideas embedded in the prudent landowner paradigm.
Investigation of teacher leadership in the context of a rural school district
(2026) Willows, Jessica; McGregror, Catherine
Teacher leadership has emerged as a dynamic force in educational change, increasingly recognized for its potential to enhance school improvement, build professional capacity, and foster more responsive learning environments (Harris & Jones, 2019; Muijs & Harris, 2006; Nguyan et al., 2020; York-Barr & Duke, 2004). However, much of the literature on teacher leadership has been shaped by urban and suburban perspectives, often overlooking the distinct conditions found within rural educational contexts. This study builds on the work of Anderson (2008) and Cherkowski and Schnellert (2017), who identified rural spaces as promising environments for teacher leadership to thrive. Using constructivist grounded theory (Charmaz, 2017) to guide the study design and data analysis, the theory responding organically, emerged from analysis of data gathered from open-ended interviews with 17 educators in a rural school district in British Columbia. The findings highlight the nature of teacher leadership and addresses challenges associated with the role of rural teacher leader: isolation, community closeness, and resource scarcity, with leadership emerging as a creative, student-centred response to these challenges. The educator responses illuminate how teacher leadership is uniquely responsive, generative and collaborative, and shaped profoundly by the rural context. The resulting theory extends understandings of teacher leadership in rural spaces by providing contextual details and descriptions of the dynamic rural environment, an explication of the processes utilized by rural teacher leadership and an illustration of the nature of this form of leadership.
Offshore carbon sequestration using renewable ocean energy as a means to meet the Paris Agreement
(2026) Moffat, Leslie; Weaver, Andrew J.; Eby, Michael
The Intergovernmental Panel on Climate Change has identified the need for negative emission technologies to limit the rise in Global Mean Surface Air Temperature (GMSAT) to 2.0°C above pre-industrial temperatures. Coupled Ocean Thermal Energy Conversion (OTEC) and Direct Air Carbon Capture and Storage (DACCS) in marine environments could create a renewable energy powered method of sequestering atmospheric CO2 to prevent surpassing, or limit overshoot, of this threshold. This research identifies the magnitude of coupled deployment required to prevent surpassing the 1.5°C and 2.0°C Paris Agreement GMSAT thresholds. Through a series of sensitivity experiments, using the University of Victoria Earth System Climate Model, the effects of the initial climate state, OTEC cold water intake depth, and deployment timeline are explored to maximize the efficiency of coupled OTEC and DACCS. Potential locations for coupled deployment are identified and used to estimate the magnitude of GMSAT reductions. Using estimates of the transient climate response to emissions and carbon emissions diagnosed from representative concentration pathways, target OTEC power production estimates were determined. By current DACCS technology standards, it was found that under low emissions scenarios, no action is required to remain below either GMSAT threshold. The potential to satisfy required power production under moderate emission scenarios varied depending on the timeline. At no point could either GMSAT threshold goal be achieved under high emission scenarios. Finally, the likelihood of remaining below the 1.5°C and 2.0°C GMSAT thresholds was significantly improved assuming an increase in the energy efficiency of DACCS technology.
Transcriptional impact of glucose enrichment on Caenorhabditis elegans oocytes
(2026) Karmani, Muskan; Templeman, Nicole M.
Reproductive aging in biological females is driven by a decline in oocyte quality, a process accelerated by metabolic stress such as high dietary glucose. The insulin/insulin-like growth factor-1 (IIS) pathway is a key nutrient-sensing regulator, and in C. elegans, reduced IIS via the daf-2(e1370) reduction-of-function mutation protects against glucose-induced reproductive decline. To uncover the molecular basis of this protection, I performed RNA-sequencing on oocytes from wild-type (N2) and daf-2(e1370) mutants after 48 hours of glucose exposure. Glucose caused distinct transcriptional responses in each genotype, suppressing 30 transcripts in wild-type and 34 different genes in daf-2(e1370) oocytes, prior to any morphological deterioration. I identified 14 transcripts that form a candidate protective signature. These genes were downregulated by glucose in wild-type oocytes, yet under the same glucose condition, they had significantly higher transcript abundance in daf-2(e1370) oocytes compared to wild-type oocytes. The most dramatic change was in icmt-1, a regulator of cell survival signaling, which was suppressed 10-fold in response to glucose in oocytes of wild-type hermaphrodites but maintained at high levels in the oocytes of daf-2(e1370) mutants despite glucose exposure. Mechanistically, glucose-suppressed genes in both genotypes were enriched for targets of intestinal transcription factors (PQM-1, CEH-60, ELT-2), suggesting glucose disrupts somatic support of the developing germline of the P1 generation. Conversely, compared to glucose-exposed daf-2(e1370) oocytes, glucose-exposed wild-type oocytes uniquely upregulated 1044 gene transcripts enriched for energetically costly membrane and transport functions, most likely related to a maladaptive response. These changes in transcript abundance predicted physiological outcomes with glucose-exposed wild-type hermaphrodites showing severely reduced late-life fertility (30.98% vs. 53.87% in controls), while daf-2(e1370) mutants maintained high reproductive success regardless of glucose enrichment. My findings demonstrate that glucose may impair oocyte quality through the suppression of critical stress defense genes. Resilience in daf-2(e1370) mutants is likely conferred by the sustained expression of this protective program, which is sufficient to maintain oocyte quality and reproductive function with age.

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