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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Crafting closeness: Building connection through collaborative creativity in Minecraft
(2026) Berger, Phaedra; Mandryk, Regan; Somanath, Sowmya
We investigate how designing to support collaborative creativity can foster social connection in interactive systems. Although creativity and social connection are conceptually linked, engaging in digital creative activity has not been examined as a mechanism for explicitly fostering social connection. We conducted a mixed-methods survey study of people who play Minecraft with others, combining measures of creativity, social connection, and features of digital collaboration with open-ended responses. Quantitative analysis revealed that both creative self-perception and the creativity support of the tool influenced the building of social capital through creative collaboration. Furthermore, creativity support was more influential in informing bonding ties than bridging ties. Qualitative thematic analysis identified three phases of the creative process (problem-finding, brainstorming, and implementation) and four experiential factors (unity, agency, playfulness, and achievement) that shaped experiences of social connection and disconnection. We contribute a set of general design implications for leveraging collaborative creativity to support social connection in digital systems.
Associations between home literacy environment, executive function, and emergent literacy among four-year-old children from low-income families
(2026) Opao, Josellie; Harrison, Gina Louise
Emergent literacy skills are a set of knowledge, skills and behaviors that serve as precursors to conventional reading and writing. Despite a wealth of research investigating the influence of the home literacy environment (HLE) on the emerging literacy skills of preschool children, findings across studies remain inconsistent. More recently, researchers have been interested in the role of executive function (EF) in school readiness skills, including emergent literacy, as well as its potential mediating role between the HLE and early literacy skills. However, their associations remain insufficiently understood, particularly among low-income preschool populations. Therefore, the present study sought to examine the direct effects of the different types of HLE activities (reading books, telling stories, and learning activities) on children’s emergent literacy skills, as well as their indirect effects operating through EF among 4-year-olds from low-income families. The three HLE activities were examined separately to determine whether each would show a differential pattern of association with emergent literacy. Using secondary data from the Baby’s First Years study, the path analysis revealed a significant direct association between EF and emergent literacy. In contrast, no significant direct and indirect effects were found between any of the three HLE activities and emergent literacy via EF. These findings underscore the important role of early EF in supporting the acquisition of early literacy skills prior to school entry.
“Only if the mother is healthy, the baby can be”: Understanding maternal health through Indian low-caste and tribal women’s perspectives
(2026) Ottsen, Patricha Jeppe; Benoit, Cecilia; Mellor, Andrea
Background: India has made substantial progress in reducing maternal mortality in recent decades. However, these collective gains obscure persistent inequities, as low-caste and tribal women continue to experience disproportionate barriers to maternal health and wellbeing. While community-based initiatives are increasingly promoted, a gap remains between low-caste and tribal women’s own priorities for maternal health and those reflected in widely implemented programs based on the World Health Organisation’s (WHO) definition of maternal health. This study seeks to address this gap by examining low-caste and tribal women’s understanding of maternal health, ultimately nuancing and contextualising WHO’s framework. Methods: Guided by an intersectionality-informed life course approach, a framework synthesis review of scholarly literature was conducted, informed by a community consultation in Kherwara, Rajasthan, India. Results were validated with the same community to refine and contextualise findings. Results: Maternal health is understood by low-caste and tribal women in India as encompassing the health of the mother and baby, and to an extent, other family members. Women in this context understand maternal health as holistic, relational, and collectively governed. According to this study, maternal health is a continuum that begins with marriage and extends through pregnancy, childbirth, breastfeeding, and beyond, as women often have multiple children and later transition into caregiving roles as sisters, friends, and grandmothers. These women also identified food security along with respectful, inclusive, and accessible health services as central to achieving maternal well-being. Discussion/Conclusion: There is a disconnect between low-caste and tribal women’s conceptualisation of maternal health and existing healthcare and supports available to them. Centring low-caste and tribal women’s articulated priorities is essential to designing equitable maternal health systems that support maternal well-being.
Hygrothermal resiliency of wood-frame wall assemblies and climate change
(2026) Croyle, Benjamin; Mukhopadhyaya, Phalguni
Moisture-related deterioration in wood-frame building envelopes is a major concern in cold and wet climates and is expected to intensify under increasingly extreme conditions driven by climate change. Existing hygrothermal performance metrics do not adequately capture the resilience of building envelopes to prolonged and extreme moisture loading. This thesis presents a comprehensive hygrothermal analysis of the resilience of wood-frame building envelopes under extreme climates. Hygrothermal simulations were conducted in WUFI Pro V6.7 to evaluate brick, stucco, composite wood, and engineered wood clad wall assemblies in six Canadian climates. Across two chapters, the wall assemblies were analyzed under increasing wind-driven rain leakage and projected future climates. Two indices were developed to assess performance: a Robustness Index, based on peak moisture content to represent maximum loss of functionality, and a Resilience Index, which evaluates the capacity for moisture dissipation and recovery over time relative to a critical threshold. These metrics were validated against the mould growth index, a widely used indicator of biodeterioration risk. The new indices were shown to be sensitive to both cladding properties and climate characteristics. In particular, the Resilience Index responded negatively in assemblies with high capillary uptake claddings in low drying potential climates. The Robustness Index was more sensitive to large amounts of concentrated wind-driven rain. The impact of climate change on the two new indices was found to be dependent on both location and cladding type. Under the tested conditions, the robustness and resilience indices demonstrated greater sensitivity to performance changes under low biodeterioration risk than the mould growth index. This work provides a functionality-based framework for evaluating and comparing building envelope designs, supporting the development of more climate-adaptive wall assemblies under both current and future environmental conditions.
Fluorescence excitation emission matrix spectral imaging microscopy
(2026) Abbey, Emma X.; Loock, Hans-Peter
With this dissertation the capabilities of fluorescence microscopic imaging are greatly extended to allow for fast chemical fingerprinting in each pixel of an image. Spatial fluorescence imaging microscopy using multispectral and hyperspectral cameras with multiplexed excitation sources has been thus far not described in the literature. Three systems to acquire fluorescence excitation-emission matrix (F-EEM) spectra are demonstrated in this work, using Hadamard-multiplexed programmable excitation light sources. Computational approaches to bypass the limitations of multi- and hyperspectral camera hardware are implemented to increase the time resolution and emission spectral resolution. The first chapter contains background and instrumentation used in F-EEM spectroscopy and multispectral imaging. Microscopy illumination methods are described as they relate to the methods used in this work, and a brief overview of parameters used for creating spatially distinct dye samples under a microscope are described. Raman spectroscopy and how it relates to multiplexed fluorescence spectroscopy is described and is followed by an overview of multivariate analysis methods used in F-EEM analysis. F-EEM imaging requires a fully programmable excitation light source and an imaging detector. The work shown here develops and uses Hadamard-multiplexed excitation sources based on instruments built by our group in the past. The basis for multiplexed spectroscopy and the theory of the Hadamard transform are described in Chapter 2. The optical design and software integration of two programmable light sources—one white-light source based on a digital micromirror array and one using an array of discrete-wavelength laser diodes—are described in Chapter 3. Acquisition of F-EEM images is done through one of two cameras—a snapshot multispectral camera using an eight-channel colour filter array, or an interferogram-based hyperspectral camera providing up to 141 spectral channels over a wide wavelength range. These commercial cameras and their integration into our systems are described in Chapter 4. The processing and analysis for F EEM images acquired using Hadamard-modulated light sources and some unique challenges to these datasets are detailed in Chapter 5. Four fluorescent components are spatially and spectrally separated in a macroscopic application of the multispectral camera and Hadamard-modulated white-light excitation source, described in Chapter 6. Here, an image of capillaries containing fluorophores and mixtures thereof is analyzed using multivariate analysis to demonstrate the spatial and spectral separation of four fluorescent components in an F EEM image. The excitation light source is then modified for use in numerous microscopy illumination methods. F-EEM microscopic imaging using three distinct combinations of excitation source and imaging detectors is demonstrated in Chapter 7 using combinations of dye emulsions. Multivariate analysis of F EEM images taken with an 8-channel multispectral camera and using seven laser diodes can find ten fluorophores in a microscopy image when those spectral signatures are known. Without prior knowledge of the fluorophores, at least four fluorescent dyes in a microscope image are separated using multivariate analysis of an F EEM photomicrograph taken using the same multispectral camera and a white-light programmable light source. The emission spectra of F EEM images acquired with the eight-channel multispectral camera are spectrally upscaled in Chapter 8 to increase the spectral resolution without hardware modifications. The upscaled spectra are demonstrated to provide a superior method of fluorophore identification and separation in an F EEM image—more fluorophores can be identified in F EEM images using upscaled spectra than raw spectra. A new computational method for increasing the time resolution of F EEM images acquired using a Hadamard-modulated excitation light source is also demonstrated. These two computational techniques allow us to obtain chemical identifiers and intensities for each of the 65,536 pixels per frame, when these frames are obtained at a rate between 3-10 per second. Numerous avenues for experiments using the programmable light sources with the multispectral and hyperspectral cameras are described in Chapter 9, along with future work on a multi-wavelength multiplexed Raman and fluorescence spectroscopy experiment.
Multi-scale remote sensing of coral reef community dynamics
(2026) Harrison, Dominica Elaine; Baum, Julia Kathleen
Ecological patterns and processes are inherently scale-dependent, yet our ability to observe and quantify how community structures vary across space and time remains a central challenge in ecology. This dissertation develops a multi-scale framework to understand how coral reef benthic communities and compositions assemble across spatial gradients and reorganize through time. Focusing on reef-building corals as marine foundation species, I integrate imaging spectroscopy, spatial modeling, and three-dimensional (3D) structural mapping to bridge organismal scales; embayment (1–3 km) and regional spatial scales (~32 km); and multiyear temporal scales spanning an acute disturbance event (a 10-month El Niño–induced marine heatwave) and a prolonged disturbance gradient (a chronic anthropogenic gradient). By linking ecological theory with remote-sensing technologies, this work addresses long-standing technological limitations in coral reef mapping, in which classifications have historically been limited to coarse benthic categories or geomorphic proxies. Using coral reefs across southwest Hawaiʻi Island, USA, as a case study, my second chapter demonstrates that fine-scale biological and morphological variation in corals can be detected and scaled using high-resolution imaging spectroscopy. Through a sensitivity analysis that combines in-situ spectral libraries, endmember modeling, simulated ocean optical properties, and Global Airborne Observatory (GAO) data, I quantify how organismal and benthic signals propagate through the water column to produce detectable airborne spectral signals. In my third chapter, I demonstrate that spectral decomposition isolates higher-order principal components that retain benthic signal, enabling their delineation, classification, and ecological attribution to benthic compositional assemblages, which I term “spectral communities.” Scaling from individual embayments to a 32-km regional coastline in chapter four, I demonstrate that spectrally derived classes, identified through spatial clustering and k-means classification of higher-order principal components, are organized along continuous benthic compositional gradients shaped by interacting, scale-dependent processes. Broad-scale patterns reflect the combined influence of environmental filtering and dispersal limitation; mesoscale structure emerges from dispersal and neighborhood effects; and fine-scale heterogeneity is driven primarily by local environmental filtering. In chapter 5, focusing on temporal coral reef dynamics in Kiritimati, Republic of Kiribati, I integrate structure-from-motion (SfM) photogrammetry and a convolutional neural network to automate benthic classification and quantify reef structural complexity, seven years after the 2015–2016 marine heatwave and across a persistent human disturbance gradient. In my final chapter, I show that acute thermal stress and chronic human disturbance interact, leading to the reassembly of coral cover, taxonomic morphology, and structural complexity. Although reefs exhibited partial recovery seven years post-disturbance, chronic human pressure constrained recovery trajectories and altered morphological composition, revealing scale-dependent resilience and functional reassembly. Overall, this dissertation develops a scalable and repeatable approach for detecting, modeling, and interpreting coral reef dynamics across space and time, providing critical tools for monitoring and conservation in a rapidly changing climate. This dissertation also demonstrates how integrating imaging spectroscopy, spatial modeling, and 3D structural mapping can address fundamental ecological questions about scale dependence, community assembly, and the processes that structure benthic composition in coral reef ecosystems.
Applying automatic speech recognition to Indigenous language documentation: A case study with Hul’q’umi’num’
(2026) Jiang, Xin He; Bird, Sonya; Urbanczyk, Suzanne Claire
The process of documenting Indigenous languages can create a large amount of audio recordings that are difficult to convert into a written form. Speeding up the transcription process using automatic speech recognition could help the Hul’q’umi’num’ Language & Culture Society to create pedagogical materials and make their recordings more accessible. In this project, I trained a language model known as XLS-R on Hul’q’umi’num’ audio recordings to determine how accurately it can transcribe Hul’q’umi’num’, whether particular linguistic and orthographic features are more difficult for XLS-R to transcribe, and what amount of time and computational resources the training takes. The model reached a CER of 11.1% and WER of 50% using 26 minutes of continuous speech. Most phonemes could be transcribed with high accuracy but the model showed difficulties with segmenting words, differentiating glottalized consonants from plain consonants, determining vowel length, and predicting the placement of glottal stops.
Investigating the function of thymic eosinophils
(2026) Gatti, Dominique; Reynolds, Lisa A.
Eosinophils reside in the thymus of humans, mice and other vertebrates, yet their function during steady-state development remains poorly defined. However, two, non-mutually exclusive, functional roles have been proposed: that eosinophils contribute to T cell development and/or support thymic tissue maintenance and repair. In this thesis we examined both proposed functions of thymic eosinophils using mouse models. We began with a broad characterization of thymic eosinophils at different time points throughout life and investigated the factors that affect their accumulation within the thymus. We then sought to understand their population dynamics and interrogated how eosinophils maintain residency in the thymus. Finally, using eosinophil-deficient mice, we investigated two possible roles that eosinophils might contribute to in the thymus. In young mice, we quantified thymocyte subsets to understand the influence of eosinophils on T cell development. In adult mice, we exploited pregnancy-induced thymic involution—a physiological model of acute thymic atrophy—to determine whether eosinophils facilitated thymic repair postpartum. Collectively, this thesis provides insight into the complexities of thymic T cell development as the cell types and signals governing thymocyte maturation are still not fully understood. Identifying the mechanisms that shape T cell ontogeny has important implications for advancing fundamental principles of developmental immunology and for improving our understanding of immune-mediated disease. Moreover, defining the functional role of eosinophils in the thymus will help clarify the potential immunological consequences of eosinophil-targeted therapies. For example, infants born to birth parents that receive eosinophil-depleting treatments may experience transient eosinophil deficiency during early life—when immune development is highly sensitive to environmental and cellular cues. By investigating both the role of eosinophils in postpartum thymic regeneration in dams and their contribution to T cell ontogeny in pups, this thesis provides a more comprehensive understanding of how eosinophils may influence thymic biology and immune development.
Stochastically constrained adversarial lifelong learning
(2026) Grant-Hagen, Mica; Mehta, Nishant
Lifelong learning is a setting of online learning where there is a sequence of tasks and each task is an online learning problem. The lifelong learning algorithm is split into two sections: the meta-level and the within-task level. In this thesis, we explore an online learning setting with a stochastically-constrained adversarial (SCA) assumption. The SCA assumption is that there is not a singular representation that works the best for each of the tasks in terms of minimizing expected losses, but that there is a representation that will become better than all other representations on average over all tasks after enough tasks have been complete. We show that in the single task setting, Decreasing Hedge with perturbed losses achieves best-of-both-worlds regret bounds under the SCA assumption. In the lifelong learning setting, we propose an algorithm with Decreasing Hedge in the meta-level and Squint in the within-task level. Under the SCA assumption in the meta-level and the Bernstein condition in the within-task level, this lifelong learning algorithm achieves best-of-both-worlds regret bounds.
Linking spiciness and oxygen variability on isopycnals off Vancouver Island
(2026) Maier, Michaela; Ianson, Debby; Hamme, Roberta Claire
Subsurface oxygen variability in coastal upwelling systems is often difficult to quantify due to sparse observations, strong seasonal dynamics, and the combined influence of physical and biological processes. Along the slope and shelf off of the west coast of Vancouver Island in the northern California Current System, subsurface oxygen concentrations are strongly influenced by the relative contributions of oxygen- rich subarctic and oxygen-poor southern source waters. This thesis investigates the link between physical properties and subsurface oxygen variability in the study area and evaluates whether numerical models can be used to estimate oxygen changes where observations are limited. Using over three decades of temperature and salinity observations and more than two decades of oxygen measurements, subsurface variability is examined on key isopycnals (density surfaces) that characterize the seasonal upwelling–downwelling cycle. This thesis identifies the σθ26.6 isopycnal as the deepest regularly upwelled isopycnal (shoaling over 100 m seasonally), highlights important seasonal cycling in both spiciness (the relative temperature and salinity of a given isopycnal, Chapter 2) and oxygen (Chapter 3), reveals notable differences in interannual variability, and uncovers significant trends. Chapter 3 also shows that spiciness effectively traces source water mixing and explains much of the observed oxygen variability on the slope, where this physical driver dominates. A robust linear relationship between spiciness and oxygen is identified, allowing oxygen to be estimated from spiciness where biological influences are weak. In Chapter 4, output from a global physical reanalysis model and a regional coupled physical–biogeochemical model is evaluated against observations. In regions and seasons where spiciness variability is realistically represented in the model data, oxygen derived from spiciness consistently outperforms directly modelled oxygen, accurately reproducing the observed variability and trends in oxygen. These results demonstrate that a physically grounded proxy-approach based on the link between spiciness and oxygen can provide meaningful estimates of subsurface oxygen variability and trends where observations are sparse. However, the reliability of these estimates depends critically on the accurate representation of the physical water-mass structure in the model, highlighting the continued necessity of sustained local observations to evaluate model performance and interpret model-derived oxygen estimates.
Le souffle fragile: Une poétique de l’inspiration en mouvement
(2026) Moreno Gomez, Angélique; Fromet de Rosnay, Emile; Landry, Pierre-Luc
This research-creation thesis investigates breath as a site of vulnerability, resistance, and transformation by combining theoretical inquiry with a video-performance creation grounded in the concept of écriture corporelle. Drawing on Mallarmé’s idea of dance as “the theatrical form of poetry par excellence” (Les Fonds dans le ballet, 1987), this thesis examines how movement—whether danced, athletic, or performative—can function as a poetic inscription capable of restoring breathing, rekindling inspiration, and alleviating anxiety. Rooted in personal experience with a complex form of asthma and anxiety, the research interrogates the conditions that render breath fragile. It mobilizes intersectional analysis, autoethnographic data, insights from medical and psychological studies, and contemporary literary and artistic works, including Les Allongées (Bélanger & Delvaux, 2022), Self-Care (Dawson et coll., 2021) and texts on mental health. Forty physical activities — dance, aerial arts, cycling, swimming, paddleboarding, yoga—were documented in an ethnographic journal and integrated into a video-performance. Emotion-driven movement emerges as a tool for emotional regulation, activating the parasympathetic nervous system and counteracting chronic anxiety. Through this lens, physical activity becomes not only a means of maintaining respiratory health but also a catalyst for creative and affective renewal. The resulting video-performance, composed of poetic fragments of gestures, landscapes, and quotations, gives form to experiences that resist verbalization: trauma, dyspnea, release, and the slow reclamation of breath. This thesis proposes a poetics of movement in which body, breath, and creation intertwine, offering a framework for understanding fragility, resilience, and the transformative potential of embodied artistic practice. -- Ce mémoire de recherche-création explore le souffle comme un lieu de vulnérabilité, de résistance et de transformation, en tissant un récit théorique et une performance vidéo axés sur l’écriture corporelle. S’inspirant de l’idée de Mallarmé selon laquelle la danse est « la forme théâtrale de poésie par excellence » (Les Fonds dans le ballet, 1987), cette étude explore comment le mouvement — que ce soit en danse, dans un sport ou dans une performance — peut devenir une inscription poétique capable de restaurer la respiration, de raviver l’inspiration et d’apaiser l’angoisse. Cette recherche, inspirée par une expérience personnelle marquée par une forme complexe d’asthme et d’anxiété, s’intéresse aux facteurs qui rendent la respiration précaire. Elle adopte une approche intersectionnelle, s’appuyant sur des données autoethnographiques, des études médicales et psychologiques, ainsi qu’un corpus littéraire et artistique contemporain, incluant Les Allongées (Bélanger & Delvaux, 2022), Self-Care (Dawson et coll., 2021) et divers textes traitants de la santé mentale. Quarante activités physiques — danse, arts du cirque, vélo, natation, planche à pagaie, yoga — ont été consignées dans un journal ethnographique et intégrées à une vidéo‑performance. Le mouvement émotif émerge comme un outil de régulation émotionnelle, en activant le système nerveux parasympathique et en neutralisant l’anxiété chronique. En effet, l’exercice physique ne se limite pas à être un moyen de préserver la santé respiratoire. Il peut aussi être un déclencheur de renouveau créatif et émotionnel. La vidéo‑performance qui en découle, composée de fragments de mouvements, de paysages et de citations, donne forme à des expériences qui ne peuvent pas être verbalisées : le traumatisme, la dyspnée, le relâchement, la lente reconquête du souffle. Ce mémoire propose ainsi une poétique du mouvement où le corps, le souffle et la création s’entremêlent. Cela offre un cadre pour penser la fragilité, la résilience et le potentiel transformateur d’une pratique artistique incarnée.
Treponema pallidum proteome response to brain microvascular endothelial cells
(2026) Mitchell, Angela; Cameron, Caroline E.
Syphilis is a major global public health concern with an estimated 8 million new cases each year. The surge in syphilis cases worldwide emphasizes the need for development of a vaccine to complement existing public health measures. Achieving this goal requires a comprehensive understanding of the pathogenic mechanisms used by Treponema pallidum subsp. pallidum, the causative agent of syphilis, including how T. pallidum traverses the blood-brain barrier (BBB) to cause neurosyphilis. Current understanding of T. pallidum’s proteome response to human brain microvascular endothelial cells (BECs), a model for the BBB, is limited. Here, we use liquid chromatography tandem-mass spectrometry (LC-MS/MS)-based label-free quantitative proteomic analyses to investigate T. pallidum protein expression following exposure to BECs. Treponema pallidum was co-incubated for 4 and 24 hours with BECs or rabbit epithelial cells (Sf1Eps; serves as a background control for the in vitro culture conditions used for T. pallidum growth). In this study, a subset of T. pallidum proteins were differentially expressed under conditions where the bacterium was exposed to BECs compared to control Sf1Ep conditions. Notably, these differentially expressed proteins included proteins in the pathogenesis-related categories of outer membrane proteins, predicted pathogenesis-related proteins, and potential human mimic proteins. This study extends our understanding of T. pallidum pathogenesis and informs syphilis vaccine development by identifying T. pallidum proteins that may be important for treponemal BBB traversal. Further, these investigations enhance our understanding of the serious sequelae of neurosyphilis, a life-threatening infection of the central nervous system by T. pallidum that can cause serious neurological issues, including stroke and paralysis.
Biophysical and functional characterization of VGLUT1-mediated glutamatergic neurotransmission in the substantia nigra
(2026) Akhavan, Adeeb; Nashmi, Raad
The substantia nigra (SN) is a critical component of basal ganglia circuitry and plays an important role in regulating voluntary movement. It consists of two major subregions, the substantia nigra pars compacta (SNc) and substantia nigra pars reticulata (SNr). Degeneration of dopaminergic (DA) neurons in the SNc disrupts basal ganglia circuitry and contributes to the motor deficits seen in Parkinson’s disease. Neurons in the SN receive synaptic input from several neurotransmitter systems, including glutamate. However, the synaptic properties of glutamatergic inputs into the SN, as well as their influence on neuronal activity within the SN, remain incompletely understood. In this study, we examined glutamatergic synaptic transmission mediated by VGLUT1-expressing inputs to SN neurons. Using a VGLUT1-Cre::ChR2 mouse line, VGLUT1-expressing presynaptic fibers were optogenetically stimulated while whole-cell patch clamp recordings were obtained from SNc DA neurons and SNr GABAergic neurons in acute brain slices. Pharmacological experiments using DNQX and APV demonstrated that excitatory postsynaptic currents in both SNc DA neurons and SNr GABAergic neurons were mediated by AMPA and NMDA receptors. Application of tetrodotoxin (TTX) and 4-aminopyridine (4-AP) confirmed that these responses were action potential dependent and monosynaptic. Short-term plasticity was examined using five pulse stimulus trains delivered at 5 Hz and 25 Hz. Overall, VGLUT1-expressing inputs exhibited predominantly depressing short-term plasticity profiles in both the SNc and the SNr, however, a range of plasticity patterns were seen, including facilitation and mixed plasticity. Depressive effects were significantly stronger during 25 Hz stimulation compared to 5 Hz stimulation for both AMPA- and NMDA-mediated responses in both regions. Response latency was significantly shorter in SNr neurons than in SNc neurons, although AMPA and NMDA receptor rise and decay kinetics were otherwise similar between regions. No significant differences in short-term plasticity were observed between SNc and SNr neurons or between AMPA- and NMDA-mediated components within either region. These results provide further insight into the synaptic properties of excitatory inputs into the SN and may help inform future studies investigating how glutamatergic signaling within this region contributes to basal ganglia function and dysfunction, including mechanisms that may be relevant for neurological disorders such as Parkinson’s disease.
The reasoning bottleneck in Graph-RAG: Structured prompting and context compression for multi-hop QA
(2026) Zarrinkia, Yasaman; Thomo, Alex
Multi-hop question answering requires connecting facts scattered across multiple documents, a task where standard retrieval often falls short. Graph-based retrieval augmented generation (Graph-RAG) addresses this by building knowledge graphs from document collections and retrieving structured context that preserves entities, relations, and community summaries. Yet strong retrieval does not guarantee strong answers. This thesis studies the reasoning bottleneck in Graph-RAG and asks whether inference-time augmentations, requiring no retraining or re-indexing, can close the gap between what the retriever provides and what the model can actually use. Evaluating KET-RAG, a leading Graph-RAG system, on three multi-hop bench marks (HotpotQA, MuSiQue, 2WikiMultiHopQA), the experiments show that 77% to 91% of questions already have the correct answer somewhere in the retrieved con text, yet accuracy reaches only 23% to 67% for a budget 8-billion-parameter model and 35% to 78% for a 70-billion-parameter baseline. Decomposing errors reveals that 73% to 84% are reasoning failures: the answer was there, but the model could not use it. Reasoning, not retrieval, is the dominant bottleneck. To address this, the thesis studies three inference-time mechanisms. First, SPARQL style chain-of-thought prompting decomposes questions into structured triple-pattern queries that mirror the entity–relationship layout of the retrieved context, improving accuracy by +2 to +14 percentage points. Second, graph-walk compression reduces the retrieved context by approximately 60% through knowledge-graph traversal with no additional model calls, adding +6 percentage points on average when paired with structured prompting on smaller models. Third, question-type routing selects be tween prompting strategies based on question structure. Surprisingly, combining all three enables a budget 8B model to match or exceed the unaugmented 70B baseline on all three benchmarks at approximately 12× lower inference cost. A transfer experiment on LightRAG, a second Graph-RAG system, confirms that structured prompting generalises across systems, while graph-walk compression works best when the retrieval pipeline produces clearly layered context, where some retrieved evidence is more central to the question than other material. The main contributions are a quantitative decomposition of Graph-RAG errors into retrieval and reasoning failures, evidence that structured prompting is a system agnostic reasoning augmentation, and the finding that low-cost inference-time interventions can close the gap between a budget model and a much larger baseline without iv any change to the retriever or index.
Civic politics should be civil: Reforming responsible conduct in British Columbia's local governments
(2026) Williams, Rhys; Lindquist, Evert
The responsible conduct of elected officials is a foundational component of effective local governance. In recent years, local governments in BC have experienced a rise in cases of misconduct from elected officials. Misconduct includes a wide range of examples. This can include anything from engaging in bullying and harassment of municipal staff to failing to disclose a conflict of interest. Challenges associated with misconduct can have broad implications such as creating division, eroding trust, and impacting collaborative decision-making processes. In turn, this dysfunction can impact the ability of a local government to deliver essential services to its community and ultimately affect the public’s confidence in their elected officials and government. Addressing the underlying factors contributing to these issues and identifying solutions is essential to improving effective local governance in BC. The purpose of this thesis is to examine the approaches for promoting and maintaining the responsible conduct of locally elected officials in BC. By exploring academic and grey literature on responsible conduct and good governance, legislative framework models, available BC codes of conduct, and case studies on specific BC local governments, this research seeks to identify solutions to BC’s responsible conduct issues to enhance good local governance. The findings from this research aim to benefit the Province of British Columbia in implementing a provincial framework model that supports an environment of good governance and responsible conduct amongst the provinces locally elected officials.
Mechanochemical fabrication of ZnO nanoparticle inks for eco-friendly low-cost thin film environmental sensors
(2026) Boakye, Gibson Asumani; Papadopoulos, Christo
The increasing demand for low-cost, scalable, and energy-efficient sensing technologies has driven significant interest in nanomaterial-based thin film sensors. This thesis presents the fabrication and characterization of zinc oxide (ZnO) nanoinks via a low processing temperature mechanochemical planetary ball milling (PBM) approach for the fabrication of eco-friendly, flexible, and low-cost gas sensors. The study focuses on establishing a low input energy, simple and scalable solution-based process that enables the direct conversion of bulk ZnO powder into functional nanoinks suitable for thin film deposition. ZnO nanoinks were prepared through wet ball milling under varying conditions, including milling speed 200 rpm to 1000 rpm, time 10 minutes to 120 minutes, and solvent type (DI water, ethylene glycol and Isopropyl alcohol), to investigate their influence on nanoparticle size, morphology, and dispersion. Thin films were subsequently fabricated by deposited the nanoinks onto a wide range of low-cost substrates including glass slide, filter, plain and lined paper, plastic polymer, foil, ceramic and flexible materials using an adjustable blade applicator technique to form films with controlled thickness (15 μm to 50 μm) and uniformity. The versatility of substrate selection highlights the potential for low-cost and flexible sensor fabrication. Material characterization was conducted using techniques such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), Raman spectroscopy, ultraviolet–visible (UV–Vis) spectroscopy, and energy dispersive X-ray spectroscopy (EDX), confirming the formation of nanoscale ZnO. Variations in milling conditions were observed to affect particle size, dispersion, and film morphology. Initial gas sensing measurements of the fabricated ZnO thin films on different substrates was evaluated under various conditions, including different gas species (Hydrogen, dry air and argon), gas concentrations (low and high), and different flow systems (static and continuous flow) at room temperature. The sensors demonstrated measurable and reproducible responses across both low and high gas concentrations, with response magnitude increasing as gas concentration increased. These results represent a proof-of-concept for room-temperature sensing using solution-processed ZnO films. The data indicated that sensors milled at 200 rpm had response times of 610–750 seconds under static flow, and 750 rpm sample reaches about 2100 seconds under continuous flow. Recovery times were generally faster with less variations, 560–660 seconds for most samples. Glass-based films generally exhibited quicker response and recovery kinetics than paper-based substrates. The sensing mechanism may be attributed to surface adsorption and desorption processes involving oxygen species, which modulate charge carrier concentration and electrical conductivity upon exposure to target gases. This work demonstrates that PBM-fabricated ZnO nanoinks enable low-cost, scalable fabrication of flexible thin film gas sensors. The preliminary gas sensing results provide insight into how processing conditions influence material properties and sensing behavior, highlighting potential for environmental, industrial, and wearable sensing applications.
Genetic and genomic characteristics of a selfish X chromosome in Drosophila testacea
(2026) Clark, Michael W.; Perlman, Steven John
Meiotic drivers are selfish genetic elements that manipulate the process of meiosis to increase their transmission, circumventing Mendel’s Law of equal segregation. Because meiosis fundamentally differs between the sexes, meiotic drivers use different mechanisms and strategies in male and female meiosis. While drivers in male meiosis use a strategy of killing meiotic products which don’t contain them, drivers in female meiosis will utilize a strategy of altering their segregation to ensuring a “winning” orientation. The mechanism that female meiotic drivers use to alter segregation is not well understood. For this thesis, I investigated a selfish X chromosome that causes both male and female meiotic drive in the woodland fly Drosophila testacea. In the first chapter, I provide an overview of meiotic drive, providing more background on the focus of my thesis, female meiotic drive. In the second chapter, I used controlled crosses to test whether one or two copies of this selfish X chromosome cause higher rates of nondisjunction, or chromosome segregation failure, in female flies. I found that females carrying one selfish X chromosome failed to transmit either of their X chromosomes at a significantly greater rate than wildtype females; this was even more pronounced in females with two selfish X chromosomes, creating a large number of sterile sons with an XO genotype. In contrast, females carrying two selfish X chromosomes almost never transmitted both of their X chromosomes. These results suggest that the two selfish X chromosomes interfere with each other over segregation in homozygous D. testacea females. Meiotic drivers tend to be structurally distinct from their non-driving counterparts, often containing chromosomal rearrangements like inversions or expansions of repetitive elements. In the third chapter, I analyze the selfish X chromosome for such structural differences, using Hi-C sequencing reads to generate chromosome-level scaffolds of the wildtype and driving X chromosomes. In doing so I demonstrate that the driving X chromosome has acquired an almost complete Wolbachia genome. Wolbachia are a group of intracellular bacteria symbionts found in insects and other terrestrial arthropods, notable for their ability to manipulate host reproduction to increase their transmission. Through comparisons with several Wolbachia genomes, I characterize the Wolbachia insertion and speculate on possible functions it may have. The work performed in my thesis helps to characterize some of the fascinating genetic and genomic characteristics of the selfish X chromosome, opening the door to further questions and research about female meiotic drive.
Systemic drivers of state formation
(2026) Iqbal, Husnain; Watson, Scott D.; Ramraj, Victor V.
This study develops a systemic theory of state formation that places dynamic change in international systems, rather than the bellicist theory’s emphasis on war occurrence, at the centre of long-term political development. War-centric scholarship has illuminated important aspects of state formation in Europe, but its explanatory reach narrows when extended beyond that historical context. The literature on non-European state formation is divided between internalist and externalist accounts that privilege a single scale of analysis and often rest on short time horizons that obscure longer-run sequences of consolidation and reversal, producing mixed findings and a fragmented scholarly consensus. Moreover, where external dynamics are considered, international politics is often treated as fixed and divided along a West/non-West binary. These limitations produce problematic implications: non-Western societies are portrayed as inherently incompatible with modern statehood or as destined for enduring weakness, while relatively strong cases of extra-European state formation remain unexplained. These problems stem from the incorporation of the contentious ‘decline-of-war’ thesis, a partial account of hierarchy, and, most critically, a neglect of systemic change in international politics. I address these limitations by integrating insights from International Relations theory, historical sociology, global history, and political geography into a framework that explains how states emerge, transform, and persist across time and space. My core claim is that state formation is fundamentally an international-systemic process and is best understood in these terms rather than in monadic or dyadic ones. Shifts in system-wide capabilities periodically reconfigure the international-political setting within which political authority is organised, territorially anchored, and spatially extended. Political units respond to these shifts through material, institutional, and ideational practices of spatial ordering. The timing and intensity of state formation are conditioned by systemic-contextual influences conceptualised as ‘structural modifiers’, including geography, technological change, transnational networks, and shifts in the forces of production and destruction that shape strategic exposure and organisational capacity. Great powers are principal actors in this process because their ordering strategies translate systemic pressures into uneven effects on spatial transformation across multiple scales, extending into national and subnational arenas, including ‘grey spaces’ where formal sovereignty and effective control diverge. These strategies are mediated by the responses of other political units and by social forces. State formation is therefore a multiscalar process that unfolds through interactions among political units as systemic conditions shift over time. Empirically, I develop a longue durée account of state formation across Eurasia to explain why the national state consolidated earliest in Europe despite parallel islands of territorial consolidation elsewhere. I also show how the national state form drew on polycentric foundations, with key practices and institutional templates developing earlier or in parallel across multiple Eurasian systems before consolidating unevenly into a dominant model across the emergent global system. The empirical chapters then apply this framework to South Asia and Southeast Asia, organised around major river systems as spatial frames. Across these cases, the findings support the claim that state formation remains historically open and spatially uneven. Even without system-wide war since 1945, sustained competitive pressures continue to drive spatial transformation through alignments, economic statecraft, infrastructural integration, and the extension of security architectures against emergent threats.
Leveraging local wisdom: The role of community knowledge in the strategic direction of BC’s community foundations
(2026) Tom, Vincent Eric; Thiessen, Susanne
Community foundations (CFs) in British Columbia are uniquely positioned as place-based philanthropic institutions whose mandates depend on their ability to understand and act on community knowledge (CK). Yet how senior CF leaders conceptualize CK, access it, and mobilize it through organizational decision-making structures remains under-researched in the Canadian philanthropic literature. Using a constructivist grounded theory methodology, this study conducted ten semi-structured interviews with senior leaders across established BCCFs to examine how CK informs strategic direction and decision-making. The analysis of these interviews produced five categories describing CK’s movement through the CK: cultivating informal access, managing multiple knowledge systems, navigating board dynamics, asserting strategic agency, and returning knowledge through reciprocity. Bringing together these categories supports an emerging theory, the Stewardship of Relational Knowledge, which articulates CK mobilization as a cyclical, non-linear process of stewardship conditioned by institutional power. The study concludes that a CF’s legitimacy as a community actor is not granted by its endowment size or grant programs but earned through its stewardship of the knowledge entrusted to it by the community.
Understanding the percieved relationship between physical activity and mental health in adolescents: A follow-up to the Adolescents' Daily Lives (ADL) study
(2026) Grant, Charlotte Grace Noelle; Buckler, Jean
Adolescence is a critical stage of human development when lifelong patterns of physical and mental health begin to take shape. Current adolescents’ levels of physical activity and mental health are lower than those of prior generations. Existing research, primarily quantitative in nature, has identified strong associations between physical activity and improved mental health. Though few studies have employed a qualitative design to incorporate adolescents’ perspectives into the robust body of evidence. The primary objective of this study was to explore the barriers and facilitators that influence physical activity engagement among adolescents who report symptoms of anxiety and depression and who do not meet the physical activity recommendations based on the Canadian 24-Hour Movement Guidelines. The sample was recruited through a secondary analysis of data from the Adolescents’ Daily Lives (ADL) study. The ADL study observed adolescents’ daily movement and mental health through wearable devices and baseline and intensive longitudinal survey data. Using a qualitative descriptive design for the current study, semi-structured interviews were conducted with a subset of participants (N= 13) experiencing both elevated mental health symptoms and low physical activity levels. Through reflexive thematic analysis, three themes were generated: (1) intrapersonal barriers, exploring participants’ mental health and daily routines, (2) interpersonal barriers, including coach and team dynamics, and (3) facilitators to physical activity engagement, such as social support and a sense of enjoyment. Participants described their perception of physical activity and mental health as bidirectional, with each one impacting the other in their daily lives. Findings highlight the importance of implementing youth-centred, autonomy-supportive, and socially inclusive physical activity environments to improve adolescent engagement in physical activity.

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