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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Picturing change: a study of the social structural determinants of health of Sub-Saharan African women migrants living with HIV in British Columbia, Canada
(2025) Joe-Ikechebelu, Ngozi; Lachowsky, Nathan; Worthington, Catherine
Since 2016, migration data reports have continuously shown that sub-Saharan Africans are the second largest ethnic group on the move to Canada. Sub-Saharan African women migrants living with HIV (SSAWMLH) in British Columbia (BC), Canada, are among those who left their sending nations because of challenging social and structural determinants of health, including HIV-related stigma. In BC, Black women represent a disproportionate share of the HIV population, including among immigrants. The aim of this culturally responsive, arts-based (photovoice and photo elicitation), community-based research study was to understand the social and structural determinants of health of SSAWMLH in BC. As community (Afro-Canadian Positive Network of BC) and academic researchers, we collected data from 12 participants (mean age of 49 years) using images and narratives through a photovoice focus group and semi-structured photo-elicitation interviews. From our participants’ narratives and pictures, we conducted data analysis using NVivo. Our first chapter revealed three themes: knowledge and awareness of U=U, HIV disclosure, and factors influencing U=U. The second chapter generated two main themes, along with sub-themes: Need for culturally connected care, along with sub-themes on i) lacking education, ii) interpersonal anti-Black racism, when accessing essential services, iii) connecting with others and forming social relationships, iv) vulnerabilised disadvantaged populations, v) religious communities, faith, and religion; and gendered discrimination, including HIV-related stigma. This dissertation concludes by reflecting on the significance of the study and the implications for the HIV response, healthcare, social services, and transnational global policy.
(Re)connecting and (re)vitalizing: Métis identity and conceptualization of self
(2025) Williams, Kennedy; Carere, Sandrina
This thesis explores the complex and deeply personal journey of (re)claiming and understanding Métis identity through genealogy, storytelling, and autoethnographic inquiry. In order to examine my lived experience as a white-passing, cisgender woman raised with stories of Métis ancestry but without tangible documentation, I investigated the nuances of identity politics, family silence, and cultural disconnection. Conducted in the MA program in child, youth, family and community studies at the University of Victoria, my research responds to both personal uncertainty and the broader systemic challenges faced by Métis youth navigating questions of identity, heritage, and belonging. My methodology consisted of critical family history and genealogy, adapted autoethnographic methods, and a kitchen table storytelling approach rooted in decolonial, intersectional, and critical race theories. With the support of family, a Métis Elder, and her husband who conducts Métis genealogy, I engaged in genealogical research and cultural reflection, and I documented my efforts to trace my lineage and examine the gaps, contradictions, and revelations in my family narratives. Another important focus of this research was to respond to the challenges commonly faced by urban Indigenous youth who are disconnected from their communities. My findings offer recommendations for practitioners working with children, youth, and families to support young people in reconnecting with their roots and histories. By centering my personal narrative within broader sociopolitical contexts, my recommendations contribute to complexifying ongoing conversations around Métis identity, Indigenous resurgence, and the roles of practitioners in navigating these tensions.
Exploring P–H activation facilitated by the [Mo–PR2]+ fragment
(2025) Dyck, Nicholas; Rosenberg, Lisa
This thesis reports the synthesis, characterization, and reactivity of metal complexes used to investigate and exploit hydridic P–H activation. This method has been used by our group to achieve stoichiometric hydrophosphination of electron-rich unsaturated substrates, demonstrating a step forward in expanding the limited substrate scope of metal-mediated hydrophosphination reactions. Chapter 2 evaluates the Lewis acidic behaviour of a new series of Mo(0) phosphenium complex, [Mo(CO)3(PR2H)2(PR2)]+ (4), in comparison to a previous series of these complexes, [Mo(CO)4(PR2H)(PR2)]+ (2), to determine how adjusting the “ancillary” coordinated metal fragment could modulate phosphenium ligand reactivity. These studies show that the greater electron density of the Mo fragment in 4 attenuates the Lewis acidity at the phosphenium ligand, but also impacts the behaviour of the complex after formation of a Lewis adduct, leading to additional reactivity such as labilization of other ligands upon phosphenium adduct formation. These differences were examined in the context of the catalytic hydrosilylation of ketones as a model electrophilic reaction. Chapter 3 investigates the substitutional lability of the P–P bond in a phosphine-phosphonium adduct complex, [Mo(CO)4(PR2H)(PR2–PR2H)]+ ([2·PR2H]+), to determine if phosphenium-catalyzed electrophilic hydrophosphination could be achieved via these compounds, an extension of the group’s previous work on the stoichiometric version of this process. While there is evidence of P–P bond cleavage of [2·PR2H]+ through substitution by incoming Lewis bases ([PF6]–, PR2H, and unsaturated substrates), catalytic anti-Markovnikov hydrophosphination mediated by a phosphenium ligand remains inaccessible from this system. Instead, these adduct complexes do act as a Bronsted acid catalyst, catalyzing the Markovnikov hydrophosphination of a 1,1-disubstituted alkene substrate. During thesestudies, phosphenium complex 2 was also shown to catalyze the dehydrocoupling of secondary phosphines via the formation of [2·PR2H]+. Chapter 4 describes the development of another series of Mo phosphenium complexes, [Mo(CO)3(bpy)(PR2)]+ (7). In the presence of substrate phosphine and alkene, these complexes exhibit no activity for phosphenium-mediated reactivity at the alkene substrate that might lead to hydrophosphination, but they react with phosphines to give the new complexes [Mo(CO)2(bpy)(PR2H)(PR2)]+ (8) and [MoH(CO)2(bpy)(PR2H)2)]+ (9). This mixture of 8 and 9 reacts with phosphines and 1,1-diphenylethylene to give mostly P–P bond formation and alkene hydrogenation, with some Bronsted acid-mediated hydrophosphination. In Chapter 5, I have investigated the ability of hydride complex 9 to act as a (pre)catalyst for a phosphenium-catalyzed phosphine dehydrocoupling reaction. Based on stoichiometric reactivity studies, I have determined that this complex can transfer hydrogen to unsaturated substrates such as azobenzene, which generates phosphenium complex 8. When this phosphenium complex reacts with substrate phosphines, P–P bond formation occurs. The resulting P–P-bonded product is substituted from Mo by additional phosphine, regenerating hydride complex 9 and achieving catalytic turnover. This new, electrophilic mechanism for phosphine dehydrocoupling shows very high catalytic activity compared to other transition metal phosphine dehydrocoupling catalysts, providing conversion and catalytic activity at room temperature that are comparable to other systems at elevated temperatures (75 – 120°C).
Data-driven aero-elastic modeling of flexible blended-wing-body aircraft
(2025) Zeinalzadeh, Aghil; Suleman, Afzal; Bras, Mario
As modern aircraft configurations like the BWB feature high-aspect-ratio wings prone to aeroelastic instabilities, there is an increasing need for real-time, constraint-aware flutter suppression methods. Traditional empirical and analytical techniques often struggle to capture time-varying dynamics near flutter speed. This thesis presents a data-driven framework for predicting the nonlinear aeroelastic response of flexible Blended Wing Body (BWB) aircraft near flutter condition. This technique is positioned within the context of active control frameworks such as Model Predictive Control (MPC), which require accurate, low-dimensional models for real-time application. The study begins with a comprehensive review of aeroelasticity, flutter suppression strategies, and emerging data-driven methods, including Dynamic Mode Decomposition with control (DMDc) and Long Short-Term Memory (LSTM) networks. To support model development, low-fidelity aeroelastic simulations are performed using SHARPy, a nonlinear simulation platform for data generation and flutter analysis. A cantilevered BWB wing is excited with gust profiles near flutter, and transient responses are recorded. This simulation data is then used to build both DMDc and LSTM models. The LSTM model is designed for sequence forecasting, enabling it to capture long-term dependencies in the time series, while DMDc provides a linear approximation of system dynamics influenced by control inputs. The SHARPy solver setup is validated using a Pazy wing benchmark, confirming its ability to reproduce unsteady behaviors such as Limit Cycle Oscillations (LCO) and transient gust responses. These results establish SHARPy as a reliable platform for data generation and flutter analysis. Building on this, the final chapter develops and evaluates the predictive models of the flexible wing based on the ORCA configuration. Flutter speed is estimated through modal analysis, followed by dynamic simulations using PRBS and sine-sweep velocity inputs. Results show that LSTM significantly outperforms DMDc near flutter, achieving less than 2% prediction error within the training velocity range. Although accuracy decreases during extrapolation, LSTM maintains a computational advantage making it highly suitable for real-time use. The chapter concludes by conceptually integrating LSTM into an MPC framework, highlighting its potential for flutter suppression and flight envelope enhancement. Overall, this thesis establishes a robust framework for real-time aeroelastic control using machine learning–based models, enabling safer and more efficient operation of flexible aircraft structures.
The baseline problem in tax analysis
(2025) Tonkin, Ryan; Macleod, Colin M.
The purpose of this project is to articulate and defend the view that both fairness and efficiency as they are understood in a great deal of tax analysis are plagued by a similar kind of comparative conceptual error, which I characterize as a baseline problem. I begin with consideration of the notions of property and ownership that best capture our existing legal and institutional practice. This practice reveals how ostensibly pretax descriptions of resources are institutionally constructed and highly contingent. I then turn to tax burden analysis as it is understood in tax policy and the orthodox approach to public finance. I join a handful of scholars who argue that this orthodoxy commits a serious conceptual error. As an alternative, I recommend conceiving of taxation as a technology embedded in a comprehensive social architecture. Resistance to this kind of approach is often directed at its alleged implausible commitment to a thoroughly conventional conception of property rights. However, I argue it has no such commitment and is consistent with a strong commitment to economic liberties. I then argue that a parallel baseline problem can be identified in two economic concepts routinely applied to assess efficiency in tax policy: Pareto efficiency and deadweight loss. I argue that both depend on comparative baselines that are often implausible or unjustified, and at the same time ignored or obscured. Finally, I consider the practice of reporting tax expenditures and the public discourse about “fair shares” as examples of baseline problems in practice.
The culture of recreation in early modern Damascus: shadow theatre and coffeehouses
(2025) Qasqas, Hala; Milwright, Marcus
The concept and periodization of ‘early modernity’ remain relatively underexamined in Islamic contexts, particularly in Bilād al-Shām. In this region, early modernity is best situated in the 18th century under Ottoman rule—a period that, while receiving increasing scholarly interest, has yet to be systematically explored. This dissertation contributes to the study of early modernity in Bilād al-Shām, and in Damascus specifically, by analyzing two emergent forms of recreation (tarfīh): coffeehouses (buyūt al-qahwa) as vital social institutions and shadow theatre (khayāl al-ẓill) as a medium of cultural production and transformation. Through these case studies, the study illuminates how leisure practices shaped public discourse and urban identity in Ottoman Damascus, thereby offering a critical reappraisal of early modernity in the Arab-Ottoman context. While the Arabic term for ‘recreation’ gained currency only in the 19th century, this study argues that the social and cultural practices associated with recreation were already taking form in the 18th century. On this basis, it proposes that early modernity in Bilād al-Shām should be understood as spanning the 18th and 19th centuries. During this transformative era, coffeehouses and shadow theatre catalyzed new modes of public interaction and political engagement that would later become foundational to modern urban life in the region. Methodologically, this study is distinguished by its integration of material and textual analysis to reconstruct the cultural and spatial dynamics of recreation in 18th-century Damascus. It centers the material remains of shadow puppets and coffeehouse architecture as key artifacts through which public sociability, expression, and everyday life were shaped. These objects and spaces are analyzed through visual interpretation, spatial mapping, and architectural documentation, positioning them as primary sources for understanding how recreation contributed to broader processes of social and cultural change. To complement this material approach, the study draws on a wide range of textual sources produced across the 18th and 19th centuries. The diaries include those by Ibn Kannān, Ibn Budayr, and Burayk; the historical and legal discourse includes those by al-Jazīrī, al-Nābulsī, and al-Qāsimī; and accounts of European travels include Russell and Littmann. The study employs theoretical frameworks developed by Henri Lefebvre, Jürgen Habermas, and James Scott, adding another layer of reflective analysis of the primary Arabic sources to provide a fresh reading enabled by the concepts of ‘public sphere’, ‘cultural resistance’, and ‘production of space’. This approach enables a rethinking of coffeehouses not merely as spaces of recreation, but as dynamic institutions embedded in the political, spatial, and cultural transformations of early modern Damascus. Overall, the significance of the study lies in rethinking Ottoman Damascus as an important cultural hub in Bilād al-Shām and a key site of early modern change by showing how coffeehouses and shadow theatre functioned as intertwined practices of recreation that shaped public life and cultural expression.
“Not bi enough:” an examination of “mostly straight” sexual identities
(2025) Matheson, Lauren; Woodin, Erica M.
Plurisexuality (i.e., attraction to more than one gender) is frequently associated with bi+ sexual identity labels such as bisexual, pansexual, or queer, however plurisexual people do not always identify with bi+ labels. "Micro-labels" such as bi-curious, heteroflexible, and mostly straight have been adopted by many plurisexual people—especially cisgender women—who feel that neither heterosexual, nor bi+ labels provide an adequate “fit” with their experience of their sexuality. Although previous research has explored outcomes associated with mostly straight identification, there is still very little research that explores the lived experience of bi-curious, heteroflexible, and mostly straight people or seeks to understand why some individuals prefer micro-labels to more established sexual identity labels. This dissertation explores the lived experience of people who use the labels bi-curious, heteroflexible, or mostly straight (i.e., mostly straight+ people) through an examination of social media comment sections (Study One) and in-depth interviews with mostly straight+ women (Study Two). Social media and interview data were analyzed using interpretative phenomenological analysis. In Study One, mostly straight+ identities were contested in online spaces. For some commenters, labels like heteroflexible, bi-curious, and mostly straight served important psychological, social, and epistemic functions. Other commenters questioned the legitimacy of mostly straight+ labels, denounced the authenticity of those who used them, and raised concerns that the labels were biphobic. For the women interviewed in Study Two, sexual identity development was marked by confusion and uncertainty, a yearning for self-understanding, and a desire to avoid misrepresenting themselves. The themes of this dissertation draw attention to shifting conceptualizations of sexual identity, issues of belongingness (specifically within the LGBTQ+ community), and the power of language to both mirror experience and shape new forms of self-understanding.
Design of an electrical power system for the MARMOTSat nanosatellite
(2025) Kellman, Ben; Suleman, Afzal; Driessen, Peter F.
This thesis presents the design, implementation, and testing of the Electrical Power System (EPS) for MARMOTSat, a 3U CubeSat developed by the University of Victoria for deployment in a Sun-Synchronous Orbit (SSO) under the Canadian Space Agency's CUBICS program. MARMOTSat serves as a technology demonstrator and scientific platform, carrying the Modular CubeSat Radio (MCR), an open-source, ITAR-free software-defined radio intended for amateur radio experiments and ionospheric research. The EPS is responsible for generating, regulating, storing, and distributing power to all satellite subsystems. A semi-centralized power architecture was developed, utilizing deployable solar arrays, lithium titanate (LTO) batteries, and maximum power point tracking (MPPT) to maximize energy generation. LTO batteries were chosen for their ability to charge at sub-zero temperatures, reducing thermal control complexity. The EPS design also incorporates subsystem level protection against radiation induced single event effects (SEE). Extensive simulations and hardware testing validated the system’s performance against power budgets and system requirements. The thesis also details the trade-offs made in power regulation and storage, as well as the design verification methodologies. MARMOTSat contributes to advancing Canadian expertise in small satellite power systems and provides a flight heritage platform for open-source space technologies, supporting broader academic and amateur radio communities.
In vitro characterization of polysaccharide utilization locus 25 from Bacteroides caccae
(2025) Alvarez, Bernadette; Boraston, Alisdair Bennett
The human gut microbiota (HGM) plays a significant role in maintaining our overall health through its dynamic composition, ability to degrade recalcitrant nutrient sources, and production of metabolites that enable host-gut microbiota crosstalk. However, many aspects of HGM function remain poorly understood. Despite the highly diverse nature of the human diet, our understanding on how the HGM metabolises the glycan and peptide components of glycoproteins is limited. Here, we investigate how polysaccharide utilization locus 25 from Bacteroides caccae (BcPUL25) could target the glycosaminoglycan (GAG) and peptide components of aggrecan, a major dietary proteoglycan in animal cartilage. Through structure-function analyses of its encoded carbohydrate-active enzymes (CAZymes), we show that BcPUL25 targets desulfated chondroitin sulfate, or chondroitin, through a unique pathway that uses a carbohydrate dehydratase to prime saturated reducing end β-glucuronic acid residues for cleavage, allowing for more efficient GAG degradation by this PUL. Similarly, biochemical assessment of both BcM60_F and BcM60_G using mucin-specific FRET substrates revealed that BcM60_G can accommodate numerous glycan structures, whereas BcM60_F exhibited more stringent peptide specificity than its counterpart and could only bind to linear glycan moieties. All tested mucin O-glycan structures have been observed to decorate the aggrecan peptide backbone. Collectively, these findings establish B. caccae as a potential glycoprotein specialist and provides the molecular framework for exploring glycoprotein metabolism by the HGM. Overall, this research contributes toward our understanding of the molecular interplay within the trifecta of microbial composition, nutrient availability, and metabolite production. In the future, studies such as this will support, and eventually result in, the development of therapeutics that will alleviate HGM-influenced disease states.
Causal theories of relativistic hydrodynamics
(2025) Hoult, Raphael; Kovtun, Pavel
The first-order textbook formulations of relativistic viscous hydrodynamics are unstable and acausal. These shortcomings may be rectified by using effective theories which maintain stability and causality. In this dissertation, which is intended to also serve as an introduction to the field, causal theories of relativistic hydrodynamics are developed and explored. Conditions are obtained for a linearized analysis to predict the non-linear causality of a theory, and constraints are found on short-wavelength dispersion relations as a consequence of ensuring stability in all reference frames. First-order causal theories of hydrodynamics are extracted from kinetic theory and holography descriptions. Finally, causal theories describing charged plasmas (one-form magnetohydrodynamics), and describing superfluids are developed.
The two solitudes in the digital age: a comparative analysis of French and Anglo-Canadian sociology journals
(2025) Colin Arce, Alan Francisco; Ravelli, Bruce
Canadian sociology is often described as two solitudes due to the separation between French and Anglo-Canadian sociologists. However, few studies have compared both languages to understand whether sociology is practiced differently in Canada depending on the language used for research. Therefore, this thesis explores whether Canadian sociology journals reflected the two solitudes over time. Using a computational methodology, I analyzed 14,528 French and English articles published in Canadian sociology journals between 1960 and 2021 to compare their publication trends. The findings reveal that half of all articles addressed topics that were published about in the two languages. I also identified four core topics in Canadian sociology that were studied in both English and French between 1960 and 2021: theory, work, crime, and family. In addition to the common topics, the two languages experienced a fragmentation, delocalization, and feminization of their research topics over time. These similar social processes show that there is more common ground between French and Anglo-Canadian sociology than is implied by the two solitudes metaphor.
Extending the reach of Gaia with Masked Stellar Autoencoders
(2025) McKay, Aydan; Fabbro, Sébastien; Venn, Kimberley Ann
I present the Masked Stellar Autoencoder, a new data-driven holistic stellar model for Galactic archaeology. The MSA is trained using the complete Gaia DR3 XP spectra catalogue by implementing a self-supervised masking algorithm to enforce the learning of the relationships within the data itself. Photometry from six additional surveys spanning optical and infrared wavelengths are integrated into the dataset, making the model robust to missing spectroscopic and photometric data. This allows the embeddings to retain accuracy beyond the depth of the XP spectra. The model was first pretrained on the ~220 million stars from Gaia DR3 with photometry for the purpose of reconstructing the information. I then demonstrate the informative embeddings produced by this astronomical foundation model with the predictive task of deriving atmospheric parameters and stellar ages using high-resolution spectroscopic surveys (APOGEE, GALAH). The model achieved mean absolute errors of 92 K in $T_{eff}$, 0.08 dex in log $g$, and 0.09 dex in [Fe/H], demonstrating its competitive position with XGBoost and transformer-based models trained with APOGEE labels. Furthermore, the model achieved mean absolute errors of 0.05 dex in [$\alpha$/Fe] and 1.3 Gyr in age, with only marginal increases in metrics when missing XP spectra. The MSA also predicts errors for the stellar parameters, which were shown to be largely representative of the predicted values, with slight underconfidence in the width of the asymmetric errors. The change in the accuracy of the predictions with pretraining dataset size was examined, and the model was leveraged to predict stellar parameters for a subset of open clusters and dwarf galaxies Leo I and Fornax. These estimates displayed a potential improvement in parallax measurements at higher distances and crowded regions. This model effectively bridges the gap between spectroscopic and photometric samples within a single, consistent framework, poised to improve with the inclusion of additional photometric surveys and upcoming Gaia releases.
Knowledge gathered from Joseph Anton: freedom and the nation through the lens of ideal and real
(2025) Talukder, Barnali; Ross, Stephen
Because of Salman Rushdie’s experience with a restricted life resulting from the national bans on both his books and freedom of movement after the controversy around The Satanic Verses, Joseph Anton: A Memoir demonstrates a vested interest in articulating the author’s ideas about freedom and the nation. While Rushdie envisions or conceptualizes freedom and nationhood in an idealized, universal, and flawless way, the reality contradicts, questions, and sometimes invalidates the conceptual ideals. Thus, knowing about Rushdie’s ideals about freedom and the nation is potentially different from navigating or knowing about the realities, which shape those ideals. Although Rushdie’s idealized freedom and nationhood inform about a universally good world, the reality provides knowledge about the underlying complexities and unresolvable dilemmas, which question the universality of such goodness. The thesis has examined how the gap between the ideal and real unfolds in Rushdie’s discussion about freedom and the nation. The thesis places the sense of universal moral goodness entertained by Rushdie’s ideals against the complex and conflicting real-world troubles; and argues that knowledge gained from Rushdie’s ideal world cannot dictate the real-world undertakings because of the latter’s tendency to embrace change and to respond to situational demands, which contributes to the creation of a different kind of knowledge. To reach this end, the thesis mainly analyzes Joseph Anton in detail preceded by the brief conceptual outlines of freedom and the nation’s essentially problematic nature and the critics’ opinions on the memoir’s deliberate and strategic narrative to uphold certain truths over others.
Predicting bankruptcy using machine learning
(2025) Idrees, Muhammad Qasim; Gulliver, T. Aaron
Bankruptcy is a serious issue in the financial sector. ML-based approaches have been widely used to predict bankruptcy, but selecting the right classifier and identifying the key features influencing Model results is essential for achieving good performance. This is especially important in the corporate sector where decision-makers may have a limited understanding of these models and their function. There is also a need for transparency and trust in their outcomes. This thesis utilizes twelve classifiers: CatBoost, RF, SVM, KNN, NB, LR, BDT, Stacking Ensemble, AdaBoost with RF, NN, FT-Transformer, and TabNet. These classifiers are evaluated in various settings using the Polish companies dataset to predict bankruptcy. The results obtained show that CatBoost is the best performing classifier. Further, SP-LIME is used to identify features that impact model decisions. SP-LIME ranks features based on their importance. A comparative analysis of SP-LIME and PCA indicates that SP-LIME identifies more influential features.
Biological and genomic responses of juvenile Pacific oysters (Crassostrea gigas) to a changing ocean
(2025) Gray, Sierra; Pearce, Christopher Michael; Bates, Amanda
Climate change, fueled by greenhouse gas emissions, is causing global atmospheric and oceanic temperatures to rise, accompanied by increased levels of carbon dioxide (CO₂) in the ocean, which has led to ocean acidification (OA). During warmer months, climate stressors (e.g. elevated temperatures), host physiology (e.g. reproductive efforts), and opportunistic pathogens like Vibrio spp. and Ostreid herpesvirus 1 (OsHV-1), coincide with each other, and exacerbate interactions into global phenomenon called oyster summer mortality syndrome, a multifactorial disease affecting oysters, particularly Crassostrea gigas (EFSA Panel on Animal Health and Welfare, 2015; Petton et al., 2015; Pernet et al., 2014). While many marine species, including bivalves (such as oysters, mussels, clams, and scallops), are adversely affected by heat and OA individually, there is relatively limited research on the combined effects of these stressors on either somatic growth or genomic responses. In this study, I investigated the individual and combined effects of temperature and pCO2 on various growth and genomic responses of juvenile Pacific oysters (Crassostrea gigas) (mean ± SD shell height: 16.6 ± 1.7 mm, wet weight: 0.47 ± 0.12 g for growth responses and shell height: 15.2 ± 1.3 mm, wet weight: 0.42 ± 0.09 g for genomic responses). Two factors (temperature and pCO2) at two levels (average summer level and IPCC-projected (RCP 8.5) future summer level) were tested in a fully-crossed experimental design, using six replicate tanks per treatment and 24 oysters per tank. Oysters were sampled at regular intervals (every 2 or 4 weeks) over 16 weeks to examine various shell biometrics (shell height, shell length, shell width, wet total weight, wet and dry shell weights, wet and dry soft-tissue weights, fan ratio, cup ratio, weight ratio) and condition index. A different subset of oysters were sampled at regular intervals (every 2 or 4 weeks) over 16 weeks for transcriptomic (RT-qPCR) analysis. Fourteen genes of interest (GOIs)—covering immunity, cellular stress, and metabolism responses—were chosen for study. The results showed that oysters were significantly impacted mostly by high temperature rather than high pCO2, both in individual and combined treatments, when analyzing both the growth and genomic results. Growth results revealed that somatic growth, weight ratio and condition indices were negatively impacted by high temperature and minimally impacted by elevated pCO2. I found that shell growth in higher temperature conditions was growing at a faster rate than in ambient temperatures, but the amount of wet tissue in high temperature condition oysters was minimal, resulting in a higher weight ratio. Similarly, condition indices were drastically different when comparing the two temperature treatments, not pCO2. Unsupervised hierarchical clustering with principal component analysis revealed numerous clusters when comparing somatic growth, with most clusters relating to week, pCO2, and temperature. Genomic results revealed that nine of the GOIs (i.e. heat shock protein 23, heat shock protein 70, hypoxia-inducible factor 1-alpha inhibitor, V-type proton ATPase catalytic subunit A, multidrug resistance 1, toll-like receptor 7, transforming growth factor, protein kinase R, macrophage expressed protein 1) were significantly upregulated by temperature, compared to only two GOIs (metallothionein and 6-phosphofructokinase) that were significantly upregulated by pCO2. Heat shock 23 and heat shock 70 genes were deemed as being the most suitable for routine monitoring as early-warning signs of oyster summer mortality. Unsupervised hierarchal clustering with principal components analysis revealed only two major clusters when comparing genomic responses, driven primarily by temperature. My results indicate that juvenile oysters are much more sensitive to heat exposure than high pCO2, with no additive effect of the two factors. Understanding how oyster growth and genes respond to both individual and combined climate-change stressors is crucial for improving predictions of oyster performance under future climate scenarios and for enhancing the sustainability of shellfish aquaculture systems that are increasingly affected by heatwaves and low-pH upwelling events. Ongoing research is essential to investigate oyster responses in controlled, environmentally-relevant, multi-stressor experiments, providing deeper insights into the potential impacts of concurrent climate change stressors and extremes on both natural and cultivated oyster populations.
Synthesis and characterization of gold nanoparticle-loaded block copolymer vectors for biomedical applications
(2025) De Francesco Calheiros, Talita; Moffitt, Matthew G.
Gold nanoparticles (GNPs) are widely studied in cancer therapy for their ability to enhance the effects of radiation and their potential as contrast agents for imaging. In this work, we developed and refined a polymeric self-assembly strategy using amphiphilic block copolymers to encapsulate gold nanoparticles. We focused on improving the system by reducing the amount of polymer required and systematically tuning parameters such as water content, polymer composition, and gold-to-polymer ratios to maximize gold loading while maintaining colloidal stability. These optimizations allowed us to increase the number of gold nanoparticles per micelle and study the potential as a contrast agent for computed tomography. Building on this optimized system, we investigated the impact of gold loading on radiosensitization by studying DNA damage in cancer cells exposed to radiation. We also studied the impact of improved average of gold per polymeric vector smaller than 50 nm in multiple cell lines. Using the γH2AX assay, although some variability was observed across different regions of the samples, the overall trend suggested that higher gold content within the micelles may be associated with increased DNA damage. However, in most cases, the differences between the gold-treated samples and the control were not statistically significant, emphasizing the complexity of the system and the need for further studies to confirm these preliminary observations. In the final part of this work, we explored the co-encapsulation of gold nanoparticles and the chemotherapeutic agent paclitaxel within the same polymeric micelles. We evaluated the cytotoxicity and apoptosis in cells treated with these dual-loaded nanoparticles, both with and without radiation exposure. The combination of gold and paclitaxel showed a synergistic effect, improving therapeutic outcomes of apoptosis compared to individual treatments.
The impact of virtual reality on cerebral hemodynamics
(2025) Farstad, Spencer; Smith, Kurt
The regulation of cerebral blood flow (CBF) is essential to match the brain’s high metabolic demand, a process governed by neurovascular coupling (NVC). Dual tasking (DT), the combination of exercise with region-specific neural activation, has been shown to augment CBF responses, yet traditional experimental approaches lack ecological validity. Virtual reality (VR) offers a dynamic, immersive medium that may stimulate CBF through visual, cognitive, and motor engagement, but no prior study has directly measured CBF during VR using gold-standard techniques. This study developed and validated a custom 3D-printed transcranial Doppler (TCD) ultrasound headpiece integrated with a Meta Quest Pro headset to quantify middle (MCAv) and posterior cerebral artery velocities (PCAv) during VR at rest and during submaximal exercise. Twenty-nine healthy adults (26 ± 5.9 y) completed standardized NVC protocols in passthrough (PT) and VR conditions, immersive VR tasks, and gameplay using the rhythm-based VR game Beat Saber. Cerebrovascular responses were assessed with TCD and complemented by extracranial vascular duplex ultrasound. Results demonstrated: (1) the 3D-printed headset reliably enabled bilateral insonation during dynamic VR tasks; (2) VR elicited NVC responses at rest and during exercise that were comparable to traditional PT protocols; (3) combining VR with exercise produced a DT effect, with additive increases in MCAv and PCAv, most notably in posterior circulation; and (4) immersive VR gameplay provoked robust, task-dependent increases in cerebral blood velocity, with cardiorespiratory demand rising in parallel with game difficulty and engagement. These findings establish immersive VR as a physiologically valid tool for assessing and provoking cerebrovascular responses, supporting its use in both research and potential clinical applications. VR-based protocols may enhance ecological validity, provide engaging rehabilitation platforms, and stimulate cerebrovascular adaptations relevant to brain health. Future work should explore longitudinal effects, sex differences, and clinical populations to determine whether acute VR-induced hyperemia translates into functional or neuroplastic benefits.
Fighting the “climate agenda”: conspiracism and the Canadian anti-climate movement
(2025) Stuart, Mary; Rowe, James K.
As the climate crisis worsens and effective action to address it becomes more critical, the forces arrayed against action are changing. Some in the ‘freedom movement’ that emerged in opposition to COVID-19 health measures have turned attention toward climate action as the next fight against government overreach. Groups in this movement are already having tangible impacts, including slowing down climate action and building power through political organizing. This research studies this emerging trend, focusing on 7 groups that are organizing to oppose climate action, informed by climate denial and conspiracy theories around authoritarian control. This study asks the following questions: 1) What are the key characteristics of this branch of the anti-climate movement in Canada? What impacts are they having? 2) How does this movement frame climate change and climate policies? 3) What language do groups use to bring people in, and how do they appeal to people’s concerns? This study is informed by Social Network Analysis (SNA), social movement theory, and multiple forms of textual analysis. Findings include that freedom groups largely focus on awareness raising tactics, but some are turning to political organizing which has the capacity to build power. The anti-climate freedom movement deploys a range of arguments to oppose climate action, including overt climate denial. Groups are also informed by conspiracy theories that climate action is being imposed my governments to justify authoritarian control. This movement is active on several different issues which offers multiple potential entry points for new recruits. Groups use populist framing to position themselves as defending the interests of everyday people against government overreach. The anti-climate freedom movement underlines the need for solidaristic progressive movements; progressive movements must build strong campaigns for climate justice that clearly connect climate solutions to other major issues today like affordability and housing.
Exploring sexuality and comedy through the performances of Huysuz Virjin
(2025) Gümüşpala, Elif Cansu; Garlick, Steve; Cleves, Rachel Hope
This thesis focuses on the stage performances of Seyfi Dursunoğlu, a Turkish male performer well known for his iconic cross-dressed persona: Huysuz Virjin. Known for her sharp wit and sexually explicit humor, Huysuz Virjin stood out against the relatively conservative norms of Turkish society, leaving a lasting mark on the country’s entertainment history. Although the artist performed for over 40 years, Huysuz Virjin also faced significant criticism, primarily for two elements of the show: cross-dressing and sexually explicit jokes. Drawing on archival research and video recordings of Huysuz Show (1994-2002), this study examines the societal acceptance of Huysuz Virjin’s performances and how sexuality and comedy operated in relation to heteronormative gender and sexual norms, using the theoretical lens of Alenka Zupančič. The defining feature of the show is its emphasis on sexuality, which, I argue, finds space through a dynamic interplay between Huysuz Virjin’s persona, Dursunoğlu’s offstage identity, and the audience. Offstage, Dursunoğlu’s masculinity aligns with the audience’s moral values, offering a shared framework of understanding. Onstage, Huysuz Virjin’s extravagant femininity and explicit jokes sharply contrast with this, while continual references to Dursunoğlu’s body beneath the persona create a fundamental tension. The audience’s belief in a stable conception of sexuality is continually disrupted by these references. This coexistence of contradictory tendencies enables humor to emerge. As a comedian, Huysuz Virjin both shares the audience’s cultural values and embodies the heteronormative codes of 1990s Turkish culture. Her traits and cross-dressing are rooted in Ottoman motifs such as the zenne figure and gazino atmosphere, creating familiarity for live and TV audiences. Beyond cultural elements, Huysuz Virjin resonates with patriarchal views of womanhood and misogynistic humor, yet the comic exaggeration of these norms exposes their incoherence and subverts them. Ultimately, I argue that Dursunoğlu’s heteronormative persona consistently accompanies Huysuz Virjin’s controversial performance, revealing the contingent, incoherent nature of sexuality and the ideological structures behind norms she embodies.
Chemodynamical analyses of the Milky Way satellites Sagittarius II and Aquarius II with GHOST: challenges in detecting dark matter in ultra-faint systems
(2025) Zaremba, Daria; Venn, Kimberley Ann
Deep photometric surveys have revealed numerous faint Milky Way satellites with absolute V-band magnitudes Mv ≳−5. Distinguishing whether these systems are dark matter-dominated ultra-faint dwarf galaxies (UFDs) or purely baryonic globular clusters (GCs) remains a key challenge. In this thesis, we explore the diagnostic power of detailed chemical abundances using high-resolution Gemini/GHOST spectra of five stars in two low surface brightness satellites – Sagittarius II (Sgr2) and Aquarius II (Aqu2). For Aqu2, the kinematics and metallicities of two stars support a dark matter-dominated UFD origin. The abundance patterns – low Na, Sr, Ba, and enhanced K – indicate inefficient star formation from only a few supernovae, possibly with enrichment from super-AGB stars. In contrast, Sgr2 shows unresolved velocity and metallicity dispersions, and its stars exhibit typical metal-poor abundance ratios with little spread. One exception is the discovery of an r-process-enhanced star (Sgr2584, [Eu/Fe] = +0.7 ±0.2), which does not clarify its nature, as such stars are found in both UFDs (Tuc III, Tuc IV, Grus II) and GCs (M15 and M92). However, radial mass segregation offers modest support for a GC classification. Motivated by this ambiguity, we examine the “Valley of Ambiguity“ – the region below MV ≲−5 in the size–luminosity (rh-Mv) plane – by dividing it into five zones of shared properties. We identify observational caveats and propose diagnostics to address UFD–GC overlap in each. We argue that only a multi-faceted approach – combining kinematic (e.g., velocity dispersions of member stars, tidal streams kinematics), dynamical (e.g., tidal resilience, mass function slopes, detections of mass segregation), and chemical diagnostics (e.g., metallicity spreads, heavy elemental deficiencies, carbon enhancement) – offers the most robust path to classification. Coupled with N-body modeling, this strategy is essential for interpreting ambiguous systems in the era of large-scale photometric and spectroscopic surveys.

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