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Towards Net Zero Energy Performance of the Montpetit Hall Building
No full textThis thesis develops a simulation-based optimization framework for the deep energy retrofit of Montpetit Hall, a multifunctional institutional facility at the University of Ottawa. Constructed in 1972, the building exhibits high energy intensity due to its mixed uses, aging envelopes and systems, and complex thermal interactions. In Ottawa's cold climate, the study aims to reduce energy consumption and improve economic performance through integrated modelling, calibration, and multi-objective optimization.
A detailed building energy model was developed in DesignBuilder and EnergyPlus and optimized in MATLAB using the Non-Dominated Sorting Genetic Algorithm II (NSGA-II). The model incorporated detailed 3D geometry, 128 thermal zones, envelope characteristics, and HVAC systems. Input data included Ottawa-specific weather records, institutional occupancy profiles, and NECB-based schedules. Baseline simulations were validated against 2022 utility data, meeting ASHRAE Guideline 14 with less than 5% Normalized Mean Bias Error (NMBE) and less than 15% Coefficient of Variation of Root Mean Square Error (CVRMSE).
The optimization process was carried out in two stages, addressing envelope retrofits and HVAC improvements. Stage 1 focused on envelope and window retrofits, identifying Pareto-optimal solutions to balance primary energy demand and NPV. Results indicated that upgrading semi-exposed floors, roofs, and south- and east-facing glazing reduced heating demand by up to 19.4%, leading to overall energy savings of nearly 13%. Double-glazed, argon-filled windows provided the most favourable trade-offs. Cost-oriented scenarios prioritized selective glazing upgrades, while maximum-savings cases involved full envelope replacements.
Stage 2 evaluated HVAC retrofits on the most energy-efficient envelope configuration, testing Variable Air Volume (VAV), Demand-Controlled Ventilation (DCV), Economizers, and Heat Recovery (HR) systems. The combination of these HVAC systems showed the highest savings in energy and economical perspective by more than 50%. Moreover, renewable retrofit strategies, photovoltaic panels (PV), solar thermal collectors, photovoltaic-thermal panels (PVT), and green roofs were also analyzed, and a comprehensive feasibility assessment was undertaken to identify the scenarios that provide the most favourable economic returns.
This research contributes to the literature by assessing the effectiveness of a two-stage retrofit optimization framework applied to a complex institutional building in a heating-dominated climate. By integrating simulation, calibration, and optimization, the study establishes a replicable methodology with direct implications for institutional decarbonization and sustainable retrofit strategies in mid-century Canadian buildings
Impacts of ketogenic diet intervention on cardiometabolic outcomes in obese, dysglycemic mice
No full textAbstract Background The ketogenic diet (KD) is widely recognized for its potential benefits in individuals with type 2 diabetes, but findings from both human and animal studies remain inconsistent. Type 2 diabetes is often comorbid with liver steatosis and atherosclerosis which are characterized by inflammation and dysregulated lipid metabolism. Moreover, whereas KD has shown mixed, sometimes detrimental, effects on circulating cholesterol levels in humans, it is currently unclear the whole-body balance of risk and benefit across hepatic, atherosclerotic, and pancreatic effects. Methods We used lean, diet-induced obese, and diet-induced obese, atherosclerotic (PCSK9 overexpression (OE)) mouse models to assess the impact of an extreme KD on cardiometabolic outcomes. Obese and PCSK9 OE mice received 10 weeks of cholesterol-supplemented HFD before 12 weeks of KD intervention whereas lean mice received KD, chow, or HFD for 12 weeks. Results KD intervention induced weight loss in obese female and PCSK9 OE male mice, but not male, wildtype mice. Across models, KD did not improve glucose tolerance or ex vivo insulin secretion, despite elevated levels of insulinotropic GLP-1 after glucose gavage. Pancreas lipids were similar between diet groups in obese mice, but liver steatosis or inflammation were generally improved in all models on KD. All KD groups had increased hepatic expression of genes for fatty acid oxidation, ketone body production, and ketone utilization. KD-intervened PCSK9 OE mice had lower circulating TNFα and chemokines (CCL2, CCL4, CXCL1, CXCL2) as well as smaller atherosclerotic lesion area relative to mice that continued on the HFD. The PCSK9 OE male mice on KD intervention also had reduced circulating LDL cholesterol but this effect was lost in mice with intact LDL receptor signaling, which also had fasting hypertriglyceridemia in line with HFD continuers. Conclusions This study demonstrates that, in mice, a high cholesterol KD can improve hepatic steatosis particularly when weight loss is achieved, compared to maintaining the western-style HFD. However, no improvements to insulin secretion and glucose tolerance were observed despite elevated post-glucose GLP-1 levels and long-term diminished requirements for insulin
Creation and Exploration of Single and Multi Antigen-Targeting Synthetic T Cell Immuno-Stimulating Treatments
No full textThe human body has developed many mechanisms and layers of defense against cancer, requiring multiple systems to fail for a malignancy to escape the immune system and pose a threat to the body. When cancers do develop, immunotherapy has emerged as a new potent way to harness these defense layers: using the body’s own immune system, reprogramming a patient’s immune cells using synthetically designed proteins that can stimulate T cells to attach to and kill cancerous cells. Here, I have explored the development and results of two distinct technological approaches for creating synthetic T cell stimulants: (1) Bi-specific T cell engagers (bTCEs); fusion proteins that combine multiple antibody-binding domains to simultaneously engage both T-cells and cancer cells in the body; and (2) Chimeric antigen receptors (CARs), fusion proteins that combine antigen targeting and immune cell stimulating domains that remain tethered to patient T cells, resulting in a living cell that can directly detect and respond to cancer cells.
I created two interoperable platforms to quickly and efficiently identify promising therapeutic TCE or CAR molecules. For TCEs, I established a high throughput function-first screening platform, allowing identification of effective TCE molecules without the need for protein purification. The second platform looked to expand a pre-existing CAR platform towards exploration of multi-antigen targeting CAR therapeutics. Specifically, two high-throughput molecular platforms were created to allow screening of multi-antigen CARs in either co-expression or tandem-CAR formats. I found that regardless of molecular strategy, multi antigen CARs maintained the ability to engage both targeted antigens and successfully suppressed tumor growth in vitro. In contrast to in vitro findings, co-expression of CARs showed superior responses in a murine xenograft model of human lung cancer, relative to tandem CAR. Despite this clear superiority of co-expression in our experiments, I do not expect this finding to generalize to all multi-antigen targeting CARs, rather these results underline the need to approach multi-antigen CARs as unique entities.
In order to expand our screening methods for CAR-T, we developed two novel assays for CAR assessment. The first assessed the avidity of CAR-Jurkat cells using flow cytometry by assessing doublet formation of CAR-target pairs. When tested using CD22 CARs, we observed unique binding maximums for each CAR which appear to be enforce by an equilibrium in a biologically driven interaction. The second is an ongoing study using cell surface proteomics, phosphoproteomics and transcriptomics to better understand why the CD22 lead 1ug36 was superior to the other CD22 CARs tested along side it. Although still ongoing, this study has revealed potentially relevant differences in signaling through LCK, LAT, CD28 and the MAPK pathways.
As a whole, this work presents novel methods and findings related to the creation and assessment of synthetic T cell immuno-stimulating treatments
Racial Discrimination at Work and Health of Canadian Workers: A Mixed Methods Study
No full textWorkplace racial discrimination remains a pervasive and harmful reality with profound implications for health and well-being. Drawing on evidence from three interrelated independent studies using both primary and secondary Canadian data, this research provides a comprehensive understanding of how workplace racial discrimination functions as both a social determinant of health and a chronic stressor contributing to adverse health outcomes and persistent health inequities. The findings demonstrate that workplace racial discrimination, manifesting through inequities in hiring, promotion, retention, and interpersonal interactions, increases the risks of significant psychological, physiological, and physical health outcomes for racialized workers. Experiencing workplace racial discrimination was strongly associated with heightened risks of anxiety, depression, stress and post-traumatic stress disorders, reinforcing mental health disparities across racialized groups. In addition, workplace racial discrimination increased perceptions of work-related stress, which in turn elevated the risk of diagnosed chronic conditions such as cardiovascular disease, Type 2 diabetes, high cholesterol, stroke effects and musculoskeletal disorders. Physiological assessments further revealed that recalling racial discrimination experiences contributes to dysregulated cardiovascular reactivity, including elevated systolic and diastolic blood pressure, as well as mean arterial pressure values above the normal range. Particularly severe forms of racial discrimination, implicating job loss, early retirement, undesirable resignation or leaves were linked to greater blood pressure increases. When incidents of racial discrimination were reported, especially when participants received acknowledgment of their experiences, physiological responses were attenuated. These results underscore the importance of personal action, recognition, accountability and institutional action in mitigating health risks. These findings underscore how workplace psychosocial stressors trigger harmful biological and physiological responses that may result in lasting health consequences.
Taken together, this research highlights workplace racial discrimination as a critical public health concern that transcends individual experiences and reflects broader organizational inequities. Conceptualizing discrimination as a chronic stressor provides an essential understanding in addressing racial health disparities. The evidence points to the urgent need for organizational reforms, robust anti-discrimination policies, and workplace practices that not only prevent discrimination but also support the mental and physical health of racialized workers. Addressing workplace racism is not solely a matter of social justice; it is a public health imperative with the potential to reduce disparities, promote workplace equity, and improve the overall well-being of diverse populations
Quality Improvement (QI) in Healthcare: A Foucauldian Discourse Analysis Examining QI Through the Lens of Advanced Practice Nurses
No full textQuality improvement (QI) in healthcare increasingly guides the activities of healthcare organizations. Heavy attention and resource allocation to QI has had significant impacts on healthcare workers, including nurses. Clinical Nurse Specialists (CNSs) are healthcare professionals with unique backgrounds who can provide a lens to understanding how healthcare QI is shaped and experienced. Using Dean’s governmentality analytic framework, historical documents that trace the emergence of QI in healthcare are analyzed alongside transcripts of semi-structured interviews conducted with CNS participants. Results of this analysis reveal that discourses of hierarchy, regulation, and performance shape experiences and understanding of QI in healthcare. Impacts of these discourses are explored, with attention to how QI discourse limits CNS identity, subjugates nursing knowledge in QI spaces, and to how QI definitions of quality fundamentally differ from nursing-centered definitions, resulting in internal conflicts. The need to re-align QI with nursing knowledge and experience is argued
Scoping Review of Sex Education Discrepancies and Sexual Violence
No full textSexual violence is a widespread issue that affects many people and leaves victims with lifelong effects on their physical and mental health. In Canada, youth and minorities are some of the highest at risk to experience sexual violence. This scoping review was performed to gain a better understanding of the current literature on the sex education of LGBTQ+ and disabled people and the correlation between sex education discrepancies and sexual violence. LGBTQ+ and disabled people were less likely to receive inclusive and comprehensive sex education and, in turn, were more vulnerable to poor health outcomes and risk of victimization. Many sex education programs instilled heteronormativity and reinforced the notion that disabled people are asexual beings. Changes to sex education need to be made that benefit LGBTQ+ and disabled youth. By including information on disabled bodies, gender identity, sexuality, and sexual violence prevention, youth are better equipped for intimate relationships
Perspectives on internal vs. external facilitation for implementing guidelines for recovery-oriented practice: a qualitative study
No full textAbstract Background Seven organizations supporting adults with mental health challenges collaborated with researchers to implement Chapter Six of Canada’s Guidelines for Recovery-Oriented Practice. An implementation strategy was developed that combined external facilitation, mixed Implementation Teams, a 12-meeting planning process, and ongoing coaching. This paper focuses on the facilitation component, specifically exploring participants’ perspectives on internal versus external facilitation within Implementation Teams. Methods Forty semi-structured individual online interviews were conducted with 32 members of Implementation Teams, including service users, providers, family members, managers, and knowledge users, along with eight researchers who acted as external facilitators. Participants discussed their experiences of implementing the guidelines supported by an external facilitator and were asked to consider how their experience may differ if it had been led by an internal facilitator. Results Thematic analysis identified seven themes relating to what was perceived as important about internal versus external facilitation: (1) Effect of facilitator position (external versus internal); (2) Flattening power hierarchies; (3) Enacting cultural shifts; (4) Understanding context; (5) Encouraging candour; (6) Building relationships, and (7) Internal facilitator identity and influence. These highlight how participants valued different skills, knowledge, and attributes in each scenario, with responses varying depending on the participant’s identity. No clear preference emerged for either approach. Instead, participants debated the benefits and drawbacks of both, where insider knowledge vied with outsider neutrality for primacy. Conclusions Whether facilitation is internal or external, its effectiveness relies on the facilitator’s ability to establish rapport, develop allies, and foster unity between Implementation Team members and the implementation setting itself. A blended approach, which integrates the strengths of both internal and external facilitators, may offer the most effective model for supporting the implementation of recovery-oriented practice. Author(s) Myra Piat1, Lucy Melville-Richards2, Megan Wainwright3, Eleni Sofouli1, Hélène Albert4, Marie-Pier Rivest4, Ian D. Graham5
A Critical Feminist Phenomenological Inquiry into Voicing through Silence
No full textThis is a critical feminist phenomenological inquiry into my experiences of fear, doubt, hesitation, and courage to voice as a domestic violence survivor. From childhood to a traumatic intimate relationship, the people around me decided for me and dictated what to do, how to speak, when to speak, even what to say when I speak. I was never heard. For my dissertation, I have decided to inquire into the ways my voice has evolved, moments where I experienced an untangling, a releasing, and a stepping into my own voice. Through phenomenological journalling, voice recording, AI-assisted imaging, and vocalizing experiences, I learned that voice is ... inherently silent; it does not require sound to exist, nor does it require others to exist. It is always already there. Voice does not need to be spoken, to be exchanged through words, through languages, either on paper, or in speech. Voice can be a gesture; a look, a stance, a tilt of the head, a subtle desire, a hesitation, a halt, stillness... Voice can be visible or invisible. Voice moves you, it moves, too. It shifts places. Sometimes it is in your throat, sometimes in your gut, sometimes in your eyes, and sometimes it is a deeper connection to something more-than-I. Voice flows, and yet stands still, too. It can be disguised, hidden; but it never disappears. Like water, voice ebbs and flows. This is an inquiry into voice and voicing, in terms of understanding what contributes to its felt presence and its moving nature. My intention in engaging in this research is to inspire and liberate others who struggle with feeling their own voice; to share with them that their voice is as long as they are
Quantum Light Emission from Waveguide-QED Systems with a Time-Delayed Coherent Feedback
No full textTo continue developing quantum technologies, such as quantum computing, quantum communication and quantum cryptography, we need reliable sources of quantum states of light. These quantum states of light can come in many forms; single photons, entangled pairs, bunched and anti-bunched light, all have uses in current quantum technologies, but for the best performance, this light must maintain its coherence. Time-delayed coherent feedback is a passive feedback method proposed for waveguide quantum electrodynamic systems to improve their performance and unlock new quantum optical phenomena. Additionally, due to its underlying non-Markovian dynamics, feedback is also an interesting theoretical problem to study. In this thesis, we use a quantum trajectory discretized waveguide (QTDW) model to simulate feedback dynamics and investigate its effects in a variety of applications. Originally proposed by Whalen in 2018, we develop the QTDW model beyond its initial implementation to now calculate quantum correlation functions, output spectra, waiting time distributions, and single photon source figures of merit. First, we present an explanation of quantum trajectory theory which is used to model the time dynamics in the QTDW approach, and discuss feedback in the linear regime to highlight the differences between Markovian and non-Markovian dynamics with coherent feedback. We next present nonlinear spectra and multi-photon effects from coherent feedback highlighting how the typical Mollow triplet is dressed by the feedback to create new resonances in the output field. This is followed by a collaborative theory and experiment work which observed our predicted non-Markovian signatures in the nonlinear output spectrum along with new non-Markovian phenomena in the linear regime. We then investigate how pulse-triggered single photon sources can be improved through the inclusion of a time-delayed coherent feedback, presenting the possible improvement to the performance figures of merit. Lastly, the modeling techniques developed for single photon sources with feedback are used to compare the performance of three new off-resonant driving techniques for on-demand single photon sources. These findings show time-delayed coherent feedback is an excellent degree of control to include in future waveguide quantum electrodynamic systems to unlock better performance and new phenomena in the system under investigation
The Role of Language Assessment for Immigration Purposes: The Case of Chinese Immigrants in Canada
No full textThrough this study, I aimed to understand how Chinese immigrants make sense of their experiences with English language testing in the Canadian immigration system. To this end, I first examined the rationales and discourses that shape Canadian immigration policy, particularly those related to language requirements. I then explored how Chinese immigrants perceive and interact with language tests, and how these experiences shape their choices, emotions, and sense of belonging in Canada. By placing these two strands of analysis in dialogue, the study revealed how official framings of language both constrain and are contested by immigrant voices. Drawing on a poststructuralist orientation, the study was guided by policy archaeology (Scheurich, 1994) for the analysis of policy and media documents, and the findings were also viewed through the lens of the model of investment (Darvin & Norton, 2015) to interpret participant data. I adopted a qualitative methodology that foregrounded participants’ voices. Participants took part in focus group discussions and collaborative co-analysis sessions. Rather than treating participants solely as data sources, I invited them to contribute as co-researchers, prioritizing their interpretations and amplifying their perspectives on language, identity, and belonging.
Document and media data analysis revealed policy trends that emphasize language as a measure of economic potential and cultural fit, often under the guise of fairness and meritocracy. These discourses reflect neoliberal narratives that privilege “ideal immigrants” who can demonstrate both productivity and adaptability through language scores. Themes from focus group data were organized primarily according to three dimensions of the model of investment—identity, ideology, and capital (Darvin & Norton, 2015).
Themes related to identity revealed tensions between external perceptions and participants’ internal sense of self, shaped by their migration histories and cultural background. Themes related to ideology reflected how participants engaged with dominant discourses of legitimacy, often navigating contradictions between policy expectations and lived realities. Themes related to capital illuminated how participants’ linguistic, cultural, and symbolic resources were recognized, devalued, or transformed through the immigration process. Cross-cutting themes included reflections on fairness, emotional labor, and systemic exclusion.
The findings contribute to the growing literature on language testing and migration by centering immigrants’ perspectives and offering a critical account of how assessment practices shape social inclusion and exclusion in Canada