Faculty of Graduate Studies Online Theses

Permanent URI for this collectionhttps://hdl.handle.net/10222/11163

Browse

Now showing 1 - 20 of 8312

Open Access
Vacant to Vibrant: Reimagining Windsor’s Built Environment Through Community-Focused Design
(2025-07-29) Golovenko, Michael; Not Applicable; Master of Architecture; School of Architecture; Not Applicable; n/a; Not Applicable; Rashida Zakia Ng; Kenneth Acton; Diogo Burnay
The “hollow city” phenomenon affects many urban centres worldwide. The downtown core of Windsor, Ontario has struggled to deal with its many vacant buildings, surface-level parking lots, and underutilized spaces. Despite a strong local identity of artistic expression and agricultural availability the downtown lacks engaging, year-round public spaces for people to enjoy. This thesis proposes the creation of a permanent cultural anchor at the heart of downtown Windsor to counteract the “hollow city” effect and promote a sustainable urban future. By integrating an all-season farmers’ market with public art, and residential spaces, this centre will be the starting point for the city of Windsor to rebuild its downtown community. The project aims to foster community connections, revitalize the area, and showcase the transformation of a vacant space into a hub of continuous public interaction.
Open Access
PROBING THE DEGRADATION MECHANISMS OF LI-ION CELLS CONTAINING SILICON AND SINGLE-WALLED CARBON NANOTUBES
(2025-08-31) Dressler, Reid; No; Doctor of Philosophy; Department of Physics & Atmospheric Science; Not Applicable; Dr. Steen Schougaard; Yes; Dr. Theodore Monchesky; Dr. Ian Hill; Dr. Jeff Dahn
This work explores the improvements that can be made to energy density by changing the active materials within the negative electrode. Current batteries use graphite as the lithium-storing active anode material as it can reversibly incorporate lithium atoms efficiently and safely. Swapping graphite for a different kind of active material such as silicon presents many advantages but also many challenges surrounding lifetime. Silicon provides almost 10x the specific capacity of graphite and is incredibly abundant but experiences strong capacity fade due to its surface interaction with the electrolyte. The volume expansion silicon experiences during lithiation leads to constant parasitic chemical reactions and mechanical degradation leading to early cell failure. The introduction of a silicon anode in place of graphite improves stack energy density by up to 59%. The work done in this thesis explores alternative anode active materials including silicon and silicon based composite particles by evaluating their energy density and cycle life. Silicon active materials showed promising results when used in conjunction with single-walled carbon nanotubes and a conductive additive. The addition of carbon nanotubes to the electrode coating process allowed the use of common binders as it creates a strong electrical network between active particles that can withstand large volume changes. To further the development of silicon negative electrodes their degradation mechanisms and failure pathways in full cells must be fully understood. In-situ stack pressure, in-situ gas evolution and post cycling differential voltage analysis are used to pinpoint and track capacity loss mechanisms in full cells. These results highlight the failure of silicon based full cells as lithium inventory losses due to the constant SEI forming reactions on the anode. These results reinforce the need for engineered silicon composites that limit the particle volume fluctuations during cycling.
Open Access
OLFACTORY DISCRIMINATION, REVERSAL LEARNING AND OVERTRAINING EFFECTS IN NRXN1+/- AND NRXN1+/+ MICE IN AN OPERANT OLFACTOMETER
(2025-08-30) Ortibus, Wyatt; No; Master of Science; Department of Psychology and Neuroscience; Received; n/a; No; Dr. Simon Gadbois; Dr. Tamara Franklin; Dr. Ian Weaver; Dr. Richard Brown
Autism spectrum disorder (ASD) is characterized by deficits in social communication, social interaction, repetitive behaviours, and poor responses to social cues. ASD is most likely caused by multiple interactions between environmental and genetic factors, including the Neurexin (NRXN) family of membrane protein synaptic organizers. These proteins are implicated in neurodevelopmental disorders, such as ASD and schizophrenia, due to their unique functions at the synapse. Neurexins are encoded by three genes (Nrxn1, Nrxn2, and Nrxn3) and classified into three isoforms (α, β, and γ), all of which are thought to have specific functions at the synapse by binding to postsynaptic neuroligins. These cell adhesion proteins modulate synaptic transmission and downstream gene regulatory networks (e.g., DAT) that control neural function. Nrxn1 gene disruption leads to synaptic destabilization and cognitive impairment, suggesting that Nrxn1 may play an important role in learning and memory. Using an operant olfactometer, we tested cognitive flexibility in wild-type (C57BL/6J) and Nrxn1+/- mice, which were developed as a model for human autism. We used rodent translational studies to examine the cognitive and behavioral consequences of alterations (e.g., knockdowns) in the Nrxn1 genes. Our novel Nrxn1+/- mice have a 140 bp deletion knocking down the α, β, and γ isoforms and have no learning and memory comparisons to wild-type controls. Mice were trained at 2-4 months of age to discriminate an initial odour pair (A vs. B) to a criterion of 85% accuracy, then to a criterion of 85% accuracy on a second odour pair (C vs. D), and then to a criterion of 85% accuracy on reversal learning of the second odour pair, where the rewarded outcomes are switched (S+ becomes S- and vice versa). Secondly, we tested for overtraining effects by overtraining mice on the second odour pair for an extra 180 trials after 85% accuracy criterion before a reversal to study its effects on total errors in reversal. Our results found no significant memory performance differences between Nrxn1+/- and wildtype (C57BL/6J) littermates in the initial odour pair discrimination, second odour pair discrimination or reversal learning discrimination. We also observed no sex differences or interactions on total errors in these discriminations, as well as no effect of overtraining on any of the genotypes compared to mice that were not overtrained. Our investigations into individual learning differences using our models determined common response phases in learning styles during tasks. We used signal detection theory to examine these learning style patterns in the olfactometer based on four possible outcomes: hits, misses, false alarms (FA), and correct rejections (CR). Using these responses, we coded discrimination and reversal learning styles into four different learning phases, which we defined as Perseverance (Misses & FA), Responds None (Misses & CR), Responds All (FA & Hits), and Respond S+ (Hits & CR). These phases of reversal learning allow us to analyze individual differences and explain how mice perform operant reversal tasks within an olfactometer. Our reversal learning theory also showed that “Learning to Learn” performance increases in reversal learning tasks is the reduction of Perseveration and Responds None responses. Future studies should consider the effects of age on reversal learning to determine whether age affects cognitive flexibility in the Nrxn1+/− mouse model.
Open Access
Adapting Health Economic Evaluation Metrics to Incorporate Estimates of Environmental Impact: An Examination of Spinal Laminectomy and Fusion Procedures in Canada
(2025-08-29) Nsitem, Kelachi; No; Master of Science; Department of Community Health & Epidemiology; Not Applicable; na; Yes; Sean Christie; Mohammad Hajizadeh; Daniel Rainham; George Kephart
Climate change is an urgent threat to public health, yet healthcare contributes substantially to environmental damage. This thesis explores how environmental impacts can be incorporated into health economic evaluations to support sustainable healthcare decision-making. A narrative review synthesized literature on ecological economics, planetary health, and sustainable healthcare to identify key themes relevant to health technology assessment. An empirical analysis examined the environmental footprint of a common surgical procedure, using real-world data to estimate emissions and explore opportunities for reduction. While environmental costs were small relative to total healthcare costs, they revealed where emissions are concentrated, and which aspects of care may be more easily changed. Patient travel emerged as a key contributor and a target for low-disruption reductions. By combining conceptual insights with practical analysis, this work demonstrates how environmental costs can be integrated into healthcare evaluation frameworks, helping healthcare systems align service delivery with broader climate and sustainability goals.
Open Access
Digital Scribing: Applications of Accessible Hyper-Imaging in Architectural Design
(2025-08-26) Samuel, Beckley; Not Applicable; Master of Architecture; School of Architecture; Not Applicable; Joyce Hwang; Not Applicable; Huschang Pourian; Roger Mullin
This thesis explores the application of scanning technology to architectural scribing techniques using digital, analogue and hybrid workflows. The project investigates ishibadate a traditional Japanese footing technique as a case study for precise scribing of manufactured material to a natural surface. The thesis then looks for avenues where digital workflows could be useful in the manufacture of precisely scribed material in an architectural context.
Open Access
INVESTIGATING THE EFFECT OF CEMENT STABILIZATION ON A SLATE WASTE ROCK
(2025-08-30) Walker, Matthew; Not Applicable; Master of Applied Science; Department of Civil and Resource Engineering; Not Applicable; n/a; Not Applicable; Gordon Fenton; Rob Jamieson; Craig Lake
Acid-producing waste rock is a by-product of urban construction, and its environmental impact necessitates proper disposal. Cement solidification and stabilization is a technique to limit the effect of acid drainage leaching from waste rock material and consists of mixing the waste rock with a cementitious binder, followed by placement in a containment cell. This technique aims to reduce water flow through the material and to increase the pH/decrease effluent contaminant concentrations. Many test methods are available to assess the performance of the stabilized material. Humidity cell testing weathers the treated material over time by repeatedly exposing the stabilized mixture to cycles of air and water. Based on humidity cell testing performed, the cement stabilization was effective in neutralizing the pH of the effluent leachate and slowing the release of most contaminants. Notable exceptions were sulfur and sulfate, which were detected in higher concentrations in the binder treated samples.
Open Access
Numerical Simulations of a Simplified Aeroengine Bearing Chamber
(2025-08-30) Boudreau, Eric; Yes; Master of Applied Science; Department of Mechanical Engineering; Not Applicable; Dr. Sophia He; Not Applicable; Dr. Mohammad Saeedi; Dr. Dominic Groulx; Dr. Baafour Nyantekyi-Kwakye
This research presents a comparison of several numerical multiphase approaches used to study a simple bearing chamber. Oil film thickness and scavenge efficiency are the main indicators used to quantify performance, and the models are validated against published experimental data. The test case conditions are meant to represent the transitional flow regime, which is the point at which viscous forces overcome the gravitational forces in the film. This case is particularly challenging to resolve due to high rotational speeds and large gradients in the film thickness. A novel approach was developed which couples Discrete Phase Modelling (DPM) for oil droplets, Lagrangian Wall Film (LWF) for thin-films, and Volume of Fluid (VOF) for thick-films. The technique was then used to validate two additional bearing chamber configurations: a protruded vent and a covered ramp leading to the scavenge pipe
Open Access
Urban-Rural Divide: Investigation of Travel Patterns, Work Arrangement Choices, and Electric Vehicle Preferences in Nova Scotia
(2025-08-28) Ghani, Maisha; Not Applicable; Master of Applied Science; Department of Civil and Resource Engineering; Not Applicable; NA; Not Applicable; Dr. Lei Liu; Dr. Uday Vnekatadri; Dr. Ahsan Habib
This thesis addresses the long-standing urban-centric bias in transportation research by foregrounding the urban–rural divide as a critical dimension for sustainable and inclusive mobility planning in the post-pandemic era. Using data from the 2022–23 Nova Scotia Travel Activity (NovaTRAC) survey, conducted across diverse communities, it evaluates multiple sampling methods, civic address, landline, cellphone, and social media, to improve representation, especially among hard-to-reach rural households. The mixed-mode approach captures socio-demographic, behavioral, and attitudinal differences across regions, offering a comprehensive portrait of how Nova Scotians live, move, and work. A Hybrid Choice (HCM) framework integrates observed and latent factors to explain both choices and motivations. The analysis focuses on two domains: public electric vehicle charging location preferences, highlighting region-specific infrastructure needs, and post-pandemic work arrangements, showing how contextual and attitudinal factors influence decisions. Findings clarify spatial inequities and inform inclusive EV infrastructure planning, flexible work policies, and sustainable mobility strategies.
Open Access
Establishing a Spatio-Temporal Atlas of Gene Expression after Traumatic Spinal Cord Injury
(2025-08-29) Dauphinee, Laura M.; Not Applicable; Master of Science; Department of Medical Neuroscience; Received; n/a; Not Applicable; Sultan Darvesh; Adam Johnston; Carman Giacomantonio; Sean Christie
Traumatic spinal cord injury (tSCI) has no cure, and effective treatments will require targeting secondary injury mechanisms at specific times and locations. This demands understanding how gene expression changes across space and time. Previous transcriptomic studies lack spatial context due to tissue homogenization. To overcome this, spatial transcriptomics was applied to characterize spinal cord gene regulation after tSCI. Female Thy1-YFP mice (14–16 weeks) received moderate T12 contusion injuries and were sacrificed at 4 hours, 48 hours, and 7 days, with a naïve control. Coronal and longitudinal sections were analyzed using the 10x Genomics® Visium HD platform. Graph-based clustering, spatially variable gene detection, differential expression, cell-type deconvolution, and ligand-receptor analysis revealed region-specific patterns among ~16,500 genes. Neuronal and glial genes decreased, while transcription factors and immune-related genes increased. Egr1, Spp1, and Apoe showed dynamic spatiotemporal responses. Findings highlight spatial transcriptomics as a powerful tool to guide development of targeted SCI therapies.
Open Access
Validation and Application of a Needs-Based Complexity Case-Mix System for Community-Based Primary Health Care Planning and Research
(2025-08-29) McDougall, Erin (Beth); Not Applicable; Doctor of Philosophy; Department of Community Health & Epidemiology; Received; Dr. Robert Reid; Yes; Dr. Ruth Lavergne; Dr. Adrian MacKenzie; Dr. Emily Marshall; Erin Christian; Dr. George Kephart
Background: Canadian provinces are transforming their primary health care (PHC) systems by developing networks of resources at community and practice levels. This leaves provinces with the challenge of determining how to meaningfully measure the PHC needs of communities and practices. Currently, methods for systematically measuring PHC needs at community and practice levels are inadequate for PHC planning and are not routinely used. Objectives: The objectives of this research were to (1) operationalize and evaluate a complexity case-mix system to measure variation in PHC needs across practices and communities, and (2) apply the system to two areas of resource alignment relevant for PHC planning a) comparing the case-mix of PHC needs of patients unattached to a PHC provider with the attached population, and b) assessing if there are systematic differences in the case-mix of PHC needs between groups with different commuting patterns for PHC. Approach and Results: The setting of this research was Nova Scotia (NS), Canada. We adapted a previously developed case-mix approach for PHC, leveraging administrative data to classify Nova Scotians into a set of needs-based segments ranging from low to high complexity. We evaluated the complexity case-mix system against a set of criteria including consistency with research on what makes PHC needs complex, utility for PHC decision makers, and segment associations with healthcare use. Segments were consistent with research on what makes PHC needs complex, and decision makers found the NS complexity case-mix system to be useful, identifying multiple areas for application including evaluating PHC performance. Segments were further found to be predictive of healthcare costs and primary care costs. We then applied the case-mix system to the unattached patient centralized waitlist in NS and found that patients who are unattached to PHC have less complex needs than the attached population. We further rostered patients to providers and found variability in commuting for PHC by community, region, and need segment, with those who commute for PHC having less complex needs compared to those who do not commute. Impact: The results of this embedded research are enhancing the capacity to design and iteratively improve community PHC systems.
Open Access
Mi’kma’ki in Bloom: Wood-Splint Flowers: Art, Resistance, and Cultural Continuity
(2025-08-26) Clarke, Ava; Not Applicable; Master of Arts; Department of History; Not Applicable; n/a; Not Applicable; Dr. Jerry Bannister; Margaret Robinson; Dr. Lisa Binkley
Wood-splint flowers, an art form practiced by Mi’kmaw artist Madeline Knockwood in the late 1930s, represent a distinct and enduring art form in Mi’kma’ki (the traditional homeland of the Mi’kmaq) today by artists who continue the practice. Mi’kmaw artists continue to make these intricate flowers, sustaining Knockwood’s legacy and reinforcing the cultural significance of this art form. Examples of Knockwood’s wood-splint flowers can be found in museums and educational collections in Kjipuktuk (Halifax, Nova Scotia), underscoring their historical and contemporary significance. This thesis uses a material culture methodology to examine wood-splint flowers as a lens through which to understand Mi’kmaw artistic traditions, their connection to Mi’kmaw ways of knowing, the euro-settler/traveler souvenir economy, and the strategic use of commodity art as a counter to assimilation pressures. I argue that wood-splint flowers are a marker of Mi’kmaw cultural continuity, yet simultaneously, material evidence of adaptation, innovation, and the enduring human drive to honour creative traditions amidst social and economic changes.
Embargo
GROWTH RATE, ELEMENTAL AND BIOCHEMICAL COMPOSITION, AND SINKING DYNAMICS OF SMALL NANOPLANKTONIC DIATOMS: IMPLICATIONS FOR SEASONAL BIOGEOCHEMICAL CYCLING IN MARINE ECOSYSTEMS
(2025-08-28) Samarasinghe Gunasekara Liyanage , Ishari Nuwanthi; Not Applicable; Doctor of Philosophy; Department of Oceanography; Not Applicable; John Berges; Not Applicable; Anya Waite; Andrew Irwin; Christopher Algar; Zoe V. Finkel
Diatoms are a highly diverse group of phytoplankton that contribute approximately half of global marine primary production and span a wide size range from less than 3 μm to more than 1000 μm in diameter. To date, most studies have focused on medium-sized diatoms between 4 to several 10s of µm in diameter. There is accumulating evidence that small nano-sized diatoms (> 2 and <4 µm in diameter) are common members of phytoplankton communities. Laboratory experiments were conducted to quantify the growth rate, elemental (C: N: Si: P), and macromolecular (protein, carbohydrate, lipids, RNA, and DNA) composition of two nanoplanktonic diatoms, Minidiscus trioculatus (CCMP 501) and Minutocellus polymorphus (CCMP 496) in comparison to the slightly larger (~5 μm) Thalassiosira pseudonana (CCMP 1335), across a gradient of irradiance (5–800 μmol photons m⁻² s⁻¹) and temperature (5–25 °C). Results showed that carbon to nitrogen (C: N) ratios were not size-dependent, but C: P, N: P, and Si: N were consistently lower in the small nanoplanktonic diatoms. The low C: P and N: P in the small nanoplanktonic diatoms are correlated with elevated of DNA: C and DNA: P. Complementary year-round field sampling (2023-2024) of surface particulate organic matter (POM) from the Bedford Basin (44.69°N, 63.64°W) supported these findings, with the lower values of C: P and N: P and higher DNA: C in the smaller size fraction (0.4 - 3 μm) relative to a larger size fraction (3 -300 μm). There were pronounced seasonal variation in C: N: Si: P in both size fractions, with spring characterized by low C: N: P and high Si: C, suggesting diatom dominance in both size fractions in spring. Elevated RNA: DNA and RNA: protein ratios during spring further supported rapid diatom growth in Spring. To evaluate whether small nanoplanktonic diatoms can sink as rapidly as larger species, a set of sinking experiments were conducted comparing the rates of M. trioculatus and M. polymorphus with that of the ~13 μm diatom Thalassiosira weissflogii (CCMP1010). Sinking experiments revealed that small nanoplanktonic diatoms, especially when forming chains or aggregates, can sink at rates comparable to or exceeding those of larger diatoms. Sinking rates increased during stationary phase, likely due to physiological and morphological changes, though species-specific responses to light and aggregate structure moderated this effect. Integrated laboratory and field data reveal that small nanoplanktonic diatoms, characterized by distinct elemental stoichiometry (low C: P, N: P), elevated DNA content, and enhanced sinking potential during aggregation significantly influence marine nutrient cycling, carbon export efficiency, and food web dynamics over different seasons.
Open Access
FIDER: A DEREGULATION TOOLKIT FOR SMALL-MARKET ELECTRICITY SYSTEMS: NOVA SCOTIA AS A CASE STUDY
(2025-08-25) Sharif, Muhammad Hassan; Not Applicable; Master of Applied Science; Department of Electrical & Computer Engineering; Not Applicable; David J. Miller; Not Applicable; Dr. Jacek Ilow; Dr. Larry Hughes
This thesis presents a practical framework, termed the FIDER Toolkit, for guiding the deregulation of electricity markets in small jurisdictions, using Nova Scotia as a case study. Drawing on global best practices from Ireland, New Zealand, and Singapore, the toolkit identifies five core components essential for successful market reform: Demand-Side Management (DSM), Market Access and Liquidity, Renewable Energy Integration, Energy Security and Diversification, and ISO Governance and Independence. Each component is supported by measurable indicators and actionable strategies. The research applies the toolkit to Nova Scotia’s electricity market, highlighting its structural limitations under a regulated monopoly and evaluating pathways to a competitive, transparent, and resilient energy system through the establishment of an Independent System Operator (ISO). The findings offer tailored recommendations to support Nova Scotia’s transition and provide a scalable model for similar small-market jurisdictions undergoing energy reform.
Open Access
Planting the Seeds for Knowledge Exchange in Canadian Forestry Perspectives from Forest Professionals on Trust, Barriers, and Preferences
(2025-08-27) Chu, Samantha; Not Applicable; Master of Environmental Studies; School for Resource & Environmental Studies; Received; Thomas Beckley; Not Applicable; Anika Cloutier; Deepa Pureswaran; Alana Westwood; Alana Lajoie-O'Malley
As environmental and social pressures affecting forestry continue to evolve, it is increasingly important that research informs practice and supports forest professionals in decision-making. The process by which research enters practice is known as knowledge exchange. Using a mixed-methods approach, combining a nationwide survey with semi-structured interviews, this study explores how forest professionals in Canada currently engage in knowledge exchange, their preferred methods for acquiring knowledge, the barriers they experience, and the state of trust they have in research, including the factors that influence that trust. The results show that forest professionals view research as a vital component of their work and primarily obtain knowledge through webinars, on-the-job training, forestry magazines, and newsletters. However, they express a strong preference for in-person methods, such as conferences and field tours. While collaboration with researchers is currently limited, many forest professionals expressed a desire for more direct involvement in research. Some also raised concerns about the applicability of academic research to operational practice. Trust in research and researchers was found to be moderately high, with particular emphasis on trust in the research process, and resilient against negative experiences. Based on these findings, this paper offers recommendations for researchers seeking to improve how they engage with forest professionals. Overall, strengthening knowledge exchange practices and being sensitive to the needs of forest professionals is essential to ensuring that research meaningfully contributes to sustainable forest management.
Open Access
Exploring Community Variation in COVID-19 Vaccine Coverage and Perceived Risks-Benefits in Bangladesh
(2025-08-28) Khan, Tahsin Shahrin; No; Master of Science; Department of Community Health & Epidemiology; Not Applicable; N/A; Not Applicable; Dr. Shelley Deeks; Dr. Dustin Gibson; Dr. George Kephart
Since launching its nationwide COVID-19 vaccination campaign on February 7, 2021, Bangladesh’s Directorate General of Health Services (DGHS) reported that, as of June 3, 2025, approximately 83.5% of the targeted population had completed their primary vaccination series. Understanding how vaccine uptake varies across sociodemographic and geographic contexts remains crucial—not only for COVID-19 but also for informing future immunization campaigns and strengthening equitable vaccine access. In Bangladesh, factors such as geographic location, health-related knowledge, perceived risks-benefits, and sociodemographic characteristics have all been associated with vaccination behavior. This cross-sectional study used data from the Rapid Mortality Mobile Phone Survey (RaMMPS), collected via Random Digit Dialing (RDD) between December 22, 2021, and July 31, 2022. The primary objective of this study was to estimate and describe variation in coverage of at least one dose of COVID-19 vaccination across sociodemographic factors and Bangladesh’s 64 districts. The secondary objective examined how perceived risks and benefits varied by sociodemographic characteristics among non-vaccinated individuals. Gender-stratified mixed-effects regression models with district-level random intercepts and sociodemographic fixed effects were employed for the first objective, and descriptive statistics were used for the secondary objective. Findings revealed high overall vaccine uptake (87.1%) with modest geographic variation. However, individual-level factors, particularly gender, age, education, occupation, and healthcare decision-making autonomy were more strongly associated with vaccine uptake than district-level differences. Notably, gender played a distinct role: women’s uptake was more closely shaped by individual and relational factors, whereas men’s uptake was more sensitive to district-level variation. These findings underscore the importance of developing gender-responsive and context-specific strategies for future vaccination efforts.
Open Access
EVALUATING THE IMPACT OF AN ONLINE TELEPHONE, GROUP-BASED COACHING INTERVENTION FOR CAREGIVERS OF CHILDREN DIAGNOSED WITH THE 22Q11.2 DELETION SYNDROME
(2025-08-28) Carbyn, Holly; Not Applicable; Master of Science; Department of Psychiatry; Received; n/a; Yes; Dr. Patricia Lingley-Pottie; Dr. Patrick McGrath; Dr. Sandra Meier
22q11.2 deletion syndrome (22q11DS) is a genetic disorder associated with psychiatric and behavioural challenges in affected children and elevated psychological distress in their caregivers. This thesis comprised two studies. Study 1 examined whether caregiver depressive symptoms were associated with internalizing and externalizing symptoms in children with 22q11DS, and whether this relationship was mediated by perceived social support. Results from 90 caregivers across North America and Europe indicated that caregiver depression was significantly associated with child externalizing symptoms, while the association with internalizing symptoms was fully mediated by perceived social support. Study 2 evaluated the implementation of a telephone, group-based online coaching intervention for caregivers. Preliminary findings suggest the intervention improved caregiver stress and anxiety, as well as child externalizing symptoms. These results underscore the importance of caregiver-focused supports in mitigating child psychiatric outcomes and highlight the potential of scalable, online interventions to address the needs of families affected by 22q11DS.
Open Access
Psychological Health and Wellness and the Impact of Six-week and Three-Month Supportive Text Messaging Program (Wellness4MDs) Among Physicians and Medical Learners in Canada.
(2025-08-26) Obeng Nkrumah, Samuel; No; Master of Science; Department of Psychiatry; Received; Dr. Ifeyinwa Mbakogu; Yes; Dr. Ejemai Eboreime; Dr. Charles Kelderhouse; Dr. Vincent Agyapong
Background: Physicians and medical trainees experience high rates of burnout, anxiety, and depression but often avoid seeking help due to stigma and confidentiality concerns. Objectives: This study aimed to (1) review the prevalence of these mental health conditions and (2) evaluate the impact of Wellness4MDs, a CBT-based supportive text messaging program, on the psychological health and wellness of physicians and medical trainees in Canada. Methods: A comprehensive literature review was conducted using databases including Medline, PubMed, Scopus, CINAHL, and PsycINFO, following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. For the intervention, participants received daily CBT-based supportive text messages over three months. Depression, anxiety, burnout, and well-being were assessed at baseline, six weeks, and three months using the PHQ-9, GAD-7, Maslach Burnout Inventory, and WHO-5. Program satisfaction was measured through an online questionnaire. Results: The review showed wide variation in mental health prevalence: burnout (4.7%–90.1% in physicians; 18.3%–94% in residents), anxiety (8%–78.9% in physicians; 10%–63.9% in residents) and depression (4.8%–66.5% in physicians; 7.7%–93% in residents). Among 806 participants enrolled in the intervention, 66 completed assessments at all follow-up points. At three months, emotional exhaustion and anxiety significantly decreased by 16.1% (p = 0.01) and 15.5% (p = 0.05), respectively, with moderate effect sizes. Depression scores did not change significantly. Participants reported high satisfaction (mean = 7.98), with most citing improved well-being and stress coping. Conclusion: These findings underscore the urgent need for accessible mental health support. Wellness4MDs offers a promising, low-cost intervention that complements traditional care and strengthens psychological resilience among healthcare professionals.
Open Access
Interventions and Implementation Strategies to Mitigate Nursing Burnout in Critical Care Nurses: A Scoping Review
(2025-08-27) Hickey, Madison; Not Applicable; Master of Science; School of Nursing; Not Applicable; Adrienne Benoit-Fagan; Not Applicable; Dr. Sheri Price; Dr. Janet Curran; Dr. Christine Cassidy
Introduction: The strain on the nursing workforce presents major challenges for the sustainability of health service delivery. With 75% of nurses in Canada reporting symptoms of burnout, this is influencing nurses leaving. This scoping review aimed to identify what interventions have been utilized to mitigate nursing burnout in critical care nurses since the COVID-19 pandemic. Methods: This scoping review followed the Joanna Briggs Institute methodology. The databases searched include MEDLINE All (Ovid), Embase (Elsevier Embase. com), CINAHL with Full Text (EBSCOhost), and PsycINFO (EBSCOhost). Results: These interventions were mapped using the Behavior Change Wheel and the Implementation in Context Frameworks. Interventions summarized in this review were diverse, with mindfulness-based interventions emerging as the most common approach. Conclusion: While most interventions focused on individuals, interventions that target multiple tiers of the healthcare system appear to offer the greatest potential for sustainable change.
Open Access
Improving the Performance of a Coastal Atlantic Wastewater Treatment Facility: Use of a Novel Adenosine Triphosphate Monitoring Tool and Investigation of Polymer Dosage
(2025-08-26) Fyfe, Sheila; Not Applicable; Master of Applied Science; Department of Civil and Resource Engineering; Not Applicable; n/a; Not Applicable; Dr. Margaret Walsh; Dr. Su-Ling Brooks; Dr. Amina Stoddart
In response to increasingly stringent federal regulations on wastewater effluent quality, municipalities are exploring optimization strategies for existing treatment facilities. This research project was conducted at the Lunenburg Wastewater Treatment Facility (WWTF), which utilized a Moving Bed Biofilm Reactor (MBBR) followed by a Dissolved Air Flotation (DAF) system in series. The objectives of this research were to establish a novel monitoring program for the MBBR using adenosine triphosphate (ATP) as a biomass indicator and determine the optimum polymer dose for the DAF process to improve effluent quality. Baseline ATP data was collected from October 2020 to November 2021. The ATP testing kits were adapted for application in the MBBR system, with weekly sampling capturing seasonal variation in biomass. Results indicated that ATP concentrations were lower than those reported for other biological treatment systems, consistent with the expected lower biomass concentration in an MBBR-DAF configuration due to the absence of return activated sludge. There was also indication of a correlation between the presence of filamentous bacteria and stress of the bioreactors, supporting the use of ATP as an early warning tool for process upsets. In parallel, a bench-scale study was conducted to test polymer dosing in the DAF system. Findings demonstrated that the WWTF could achieve the target effluent total suspended solids (TSS) concentration of 25 mg/L without polymer addition. Furthermore, excessive polymer dosing was shown to hinder solids removal, contributing to aesthetic issues in the effluent. These results suggest that significant cost savings and process improvements could be achieved by minimizing polymer use. Overall, this research highlights the potential of ATP-based monitoring for MBBR systems and emphasizes the importance of dosage selection in chemical treatment at wastewater treatment facilities in order to enhance performance and meet evolving regulatory and community expectations.
Open Access
Improving Emergency Medical Services Using Simulation And Machine Learning
(2025-08-25) Qixuan, Zhao; Yes; Doctor of Philosophy; Department of Industrial Engineering; Not Applicable; Valérie Bélanger; Not Applicable; John Blake; Majid Taghavi; Peter Vanberkel
Emergency Medical Services (EMS) are critical to public health, yet they face persistent challenges, particularly during periods of surge. This thesis advances the integration of machine learning (ML) and simulation methodologies to enhance EMS decision-making, resource allocation, and system resilience. First, a systematic literature review is conducted to investigate how simulation and ML can be combined in healthcare. This literature review provides a detailed categorization and research gaps. Second, an unsupervised ML clustering model based on genetic algorithms is developed to define EMS surge levels. This model objectively categorizes surges using EMS operational data without relying on subjective data. The model is adaptable, allowing for facilitation of regional customization and generalizability. A case study is conducted to test this model. The results show that the proposed model can correctly describe 92% of the busy periods. Third, the thesis questions the suitability of conventional ML evaluation metrics when ML models are used to generate inputs for simulation models. Using a discrete event simulation (DES) of EMS system, the study demonstrates inconsistencies between conventional metrics and simulation-based evaluations, highlighting the need for context-specific evaluation strategies. Fourth, this thesis proposes ML-based approaches for predicting ambulance travel time, comparing three artificial neural networks (ANN), Google Maps, and the traditional KWH model. Results show that ANN model aligns closely with historical data, making it more suitable for EMS simulation and decision-making, despite requiring more complex feature inputs. Finally, a comprehensive DES model is developed with the integration of ML-derived parameters for ambulance travel time and emergency department destination selection. The simulation model is validated against historical data of surges and used to test operational improvements, including ambulance upstaffing, alternative transportation, and surge-based low-priority call holding. Robustness analyses are conducted to test the potential of these strategies to enhance EMS performance under various demand scenarios. Collectively, this work contributes a novel framework for defining EMS surge levels and EMS simulation modelling. The findings underscore the importance of context-aware ML evaluation and offer scalable tools for improving EMS operational efficiency.