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Recent Submissions

Access status: Open Access ,
The Relative Importance of Social and Health Spending in Determining Health Outcomes Across Selected OECD Countries From 1990 to 2019
(2025-11-25) McCann, Bridget; Not Applicable; Master of Science; Department of Community Health & Epidemiology; Not Applicable; Not Applicable; Not Applicable; Mark Asbridge; Ruth Lavergne; Daniel Dutton
Governments in high income countries continue to prioritize health care spending to improve population health, yet evidence suggests that broader social factors also influence health. This study examined whether greater investment in social spending relative to health spending is associated with improved population health across 26 OECD countries from 1990 to 2019. Using standardized international data and two-way fixed effects regression models, we assessed the association between the ratio of social-to-health spending and five health outcomes: life expectancy, potential years of life lost, infant mortality, low birth weight, and maternal mortality. Higher social-to-health spending ratios were associated with better life expectancy, potential years of life lost, and infant mortality. Outcomes for low birth weight and maternal mortality showed inverse associations with the ratio over time. These findings suggest that redirecting government spending toward social programs may be a more effective way to improve health outcomes than prioritization of health spending.
Access status: Open Access ,
Adapting Eco-Driving Feedback and Historical Visualization for Vessel Dashboards
(2025-11-25) Rahman, Yeaminur; Not Applicable; Master of Computer Science; Faculty of Computer Science; Received; n/a; Not Applicable; Dr. Rita Orji; Dr. Stephen Brooks; Dr. Derek Reilly
Maritime navigation is a significant source of greenhouse gas emissions. While large-scale cargo shipping is the major contributor, smaller maritime operations, including patrolling, fishing, public transit, and recreation, present unique challenges and opportunities for power management. Fuel consumption, power conversion, and environmental data can permit environmentally conscious and cost-effective decision-making when driving a boat. To achieve this, we need to understand how best to integrate such data into boat dashboard interfaces. In this work, we design an Eco Dashboard inspired by eco-driving feedback dashboards in the automotive industry, as well as a variant of the Eco Dashboard that additionally visualizes historical route and fuel consumption data (Eco + Historical Dashboard). In an experimental simulation (N = 30) involving 12 experienced mariners and 18 novices, we compared both interfaces with a typical boat dashboard that presented fuel and speed. Our findings suggest that dashboards incorporating historical data, alongside eco-driving features, improve fuel efficiency and decision-making, particularly for non-experienced users. The Eco Dashboard supported real-time adjustments during complex navigation, whereas the Eco + Historical Dashboard enhanced route planning and confidence in longer-term decisions. Participants also reported greater confidence and reduced cognitive load when using these systems. These results provide valuable insights for the future design of maritime dashboard systems, offering a pathway to more effective and environmentally conscious navigation tools.
Access status: Open Access ,
KAPOSI’S SARCOMA-ASSOCIATED HERPESVIRUS REMODELS THE NUCLEUS AND ENDOPLASMIC RETICULUM DURING INFECTION
(2025-11-18) Wilson, Alexa; Yes; Doctor of Philosophy; Department of Microbiology & Immunology; Not Applicable; Dr. Sumita Bhaduri-McIntosh; Yes; Dr. Roy Duncan; Dr. Barbara Karten; Dr. Christopher Richardson; Dr. Craig McCormick
Kaposi’s sarcoma-associated herpesvirus (KSHV) is the etiologic agent of Kaposi’s sarcoma, primary effusion lymphoma, multicentric Castleman’s disease and KSHV-induced cytokine syndrome. KSHV follows a biphasic infectious cycle: upon infection it establishes latency with the genome maintained as an episome tethered to host chromatin, and cellular stress triggers expression of the replication and transcription activator RTA (ORF50) which initiates lytic replication, a program featuring heightened viral gene expression and genome replication. Lytic replication places a heavy burden on the endoplasmic reticulum (ER), the site of folding and modification of secreted and transmembrane proteins and activates the unfolded protein response (UPR). The UPR is coordinated by three ER-localized sensors, PERK, IRE1 and ATF6, which initiate complementary transcriptional programs that expand folding capacity and lipid synthesis, while PERK signaling attenuates cap-dependent translation and can trigger apoptosis if stress is unresolved. KSHV inhibits each arm of the UPR during lytic replication, but the viral factors and mechanisms responsible are incompletely understood. In this thesis I report that the early viral E3 ubiquitin ligase K3 directs K63-linked polyubiquitination of PERK, targeting PERK for lysosomal degradation and thereby terminating PERK signaling. ER stress enhanced K3-dependent PERK turnover, consistent with signal-dependent PERK degradation which converts PERK activation into PERK removal. I demonstrate that the viral G protein-coupled receptor vGPCR induces ER stress and potentiates K3-dependent PERK degradation, and that K3 reciprocally ubiquitinates vGPCR to promote its lysosomal clearance. Therefore, K3 regulates both a source of ER stress and the principal PERK-dependent response. Infection with a K3-deficient virus results in the dysregulated accumulation of viral proteins despite unchanged transcription, implicating K3 in post-transcriptional control of viral proteostasis. Subsequent ultrastructural and live-cell microscopy revealed extensive nuclear membrane remodeling during lytic replication in both WT and ∆K3 infections, pertaining to expansion of the Type-I nucleoplasmic reticulum. These invaginations serve as sites for primary envelopment and nuclear egress, and I document genetically and chemically labeled capsids traffic through these compartments into the cytosol. Together, these studies show that KSHV coordinates robust remodeling of ER and nuclear membranes to support productive infection, with K3 central to manage ER-stress and viral protein proteostasis.
Access status: Open Access ,
How Relational Continuity, Serious Mental Illness, and Substance Use Disorders Shape Management of Diabetes and Hypertension: Analysis of Population-Based Administrative Health Data in British Columbia
(2025-11-20) Poarch, Eric; Not Applicable; Master of Science; Department of Community Health & Epidemiology; Received; NA; Not Applicable; Dr. David Rudoler; Dr. Cindy Feng; Dr. Ruth Lavergne; Dr. Mark Asbridge
People with serious mental illness (SMI) and substance use disorders (SUD) are at higher risk of chronic physical diseases like diabetes and hypertension and related acute complications, but face barriers to chronic disease management (including longitudinal monitoring in primary care, medication management, and laboratory testing). It remains poorly understood how relational continuity and treatment for comorbid SMI and/or SUD shape recommended management of diabetes or hypertension. I used linked BC administrative health data from April 1, 2020 to March 31, 2023 to compare patterns of chronic disease management among patients with diabetes or hypertension treated for comorbid SMI/SUD using descriptive statistics (frequency, means, and standardized differences). Modified-Poisson regression models were used to calculate adjusted risk ratios between relational continuity and recommended management and included interaction terms to evaluate whether associations were modified by SMI/SUD treatment. Findings reveal disparities in chronic disease management among people treated for SMI and/or SUDs.
Access status: Embargo ,
Active Material Investigations in Lithium- and Sodium-Ion Batteries
(2025-11-18) Garayt, Matthew; Yes; Doctor of Philosophy; Department of Physics & Atmospheric Science; Not Applicable; Jean-Marie Tarascon; Not Applicable; Jeff Dahn; Theodore Monchesky; Michael Metzger
This thesis focuses on both methods to evaluate and produce new lithium- and sodium-ion battery active materials, as well as studying the use of new active materials. It focuses on the development and use of single-layer pouch cells, all-dry synthesis of mid-nickel positive electrode materials for lithium-ion batteries, and the development and use of lead-containing negative electrode materials for sodium-ion batteries. The first part of the thesis develops a method to make single-layer pouch cells and shows the benefits of this form factor. First, a comparison between single-layer pouch cells, coin cells, and stacked pouch cells is made, showing that when single-layer pouch cells are made without a negative electrode overhang, they give the best possible electrochemical performance. Finally, single-layer pouch cells are used in a case study comparing LFP and NMC full cells. The second part of the thesis develops an all-dry synthesis technique to make NMC640 in a water- and waste-free process. The all-dry synthesis consists of mixing transition metals and metal oxides with a lithium source and an optional tungsten coating in an auto grinder before calcination. The best all-dry synthesized materials with 0.3 mol% tungsten coating perform as well or better than a commercial NMC640 material in electrochemical half cell evaluations. The remaining parts of the thesis introduce lead as a promising sodium-ion negative electrode material. First, in half cell testing, it is found that lead negative electrodes with high active material loadings can cycle with no capacity loss when their electrodes contain single-walled carbon nanotubes and the electrolyte solvent is monoglyme. However, due to the large volume change of lead during sodiation, the lead particles break down into smaller particles and cause overall restructuring of the electrode. This repeated volume change also causes irreversible capacity loss in full cells. An initial attempt is made to make lead-carbon composite active materials that can mitigate the effects of the volume change. Overall, this thesis provides insights into new active materials, new methods to test them, and new production processes for them to produce lower cost and longer lifetime batteries.
Access status: Open Access ,
MICROGLIAL ACTIVATION IN THE CAT DORSAL LATERAL GENICULATE NUCLEUS FOLLOWING RETINAL INACTIVATION
(2025-11-18) Rizwan, Safiya; Not Applicable; Master of Science; Department of Clinical Vision Science; Received; Donald Mitchell; Not Applicable; Nadia Dicostanzo; Kevin Duffy
Amblyopia is the leading cause of monocular vision loss in children. Success in treating amblyopia using conventional methods such as patching and atropine penalization are hindered by compliance issues, rigid treatment schedules, and a short treatment window during young childhood. Thus, alternative treatments addressing these barriers are necessary to improve visual outcomes. Retinal silencing, by administering intravitreal injections of tetrodotoxin (TTX), is a potential treatment for amblyopia in lieu of patching or penalization. Fellow eye retinal silencing has shown good results in promoting visual recovery of the deprived eye, with no permanent detriment to the silenced eye. However, the underlying mechanisms that protect the eye during silencing are not fully understood. Microglia are a subtype of glial cells involved in mediating the development of the synaptic network in the central nervous system. The current study sought to determine if microglia are involved in a homeostatic response that protects the synaptic network against lowered neural activity elicited by retinal silencing. In other words, how are synapses-serving the inactivated eye protected from perturbation? Microglial activation was investigated as a possible protective mechanism by measuring ionized calcium binding adaptor molecule 1 (Iba1) immunolabeling within the silenced- eye layers of the dorsal lateral geniculate nucleus. The results of this study revealed that retinal silencing in young animals activates microglia, and that retinal silencing in older animals did not elicit such activation. These findings raise the possibility that activation of microglia mediates a homeostatic response to protect against retinal silencing-induced synaptic modifications. The current study also showed that retinal silencing in younger animals activates microglial transiently, as activation is not sustained following TTX with a period of binocular vision. As TTX treatment stands as a possible alternative treatment for human amblyopia, it is important to understand how TTX affects the synaptic network of the visual system.