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Ultimate Concern in Teachers' Lives and Practice: A Hermeneutic Inquiry
No full textIn this qualitative study I explore the experience of the infinite, eternal, and unconditional in the
lives of six Western Canadian public high school teachers, investigating how their sense of what
Paul Tillich calls “ultimacy” co-arises with their own particular deep personal interests or
practices, and how such interests or practices reflect an ultimate concern in their work as
teachers. Each teacher in this study was picked because they possessed some deeply held
personal interest that lay outside of their teaching practice, though which also influences their
practice in some way. Chapter One details the origins of my own ultimate concern and my
passionate interest in the martial arts. I also outline the beginnings of a conceptual framework for
thinking about the experience of ultimacy through teacher stories and hermeneutic inquiry. In
Chapter Two, I proceed with a review of literature that focuses on key moments in the personal
and professional lives of teachers, leading to personal transformation and spiritual insight. In
Chapter Three, I introduce my research participants, how I selected them, my methods of data
collection, and I elaborate on the philosophy and process of data interpretation in hermeneutics.
Because one of the basic tenets of hermeneutic study is that it begins with being called or
addressed, I argue that this approach meshes well with the experience of ultimacy, which arrives
unannounced and leaves alluring traces that draw us. In this study, such traces are found in text
that come from written or spoken teacher stories. The questions which provoked these stories
follow William F. Pinar’s four moments of currere. In Chapter Four, I explore the origins of
each of the six teachers’ sense of ultimacy and related future intentions, Pinar’s regressive and
progressive moments. In Chapter Five, I detail my dialogue with teachers reflecting on the state
of their passions or practices with which ultimacy co-arises, and discuss how present challenges
prompt analysis, Pinar’s third moment. In Chapter Six, I ask how ultimacy guides teacher
Ultimate Concern in Teachers’ Lives and Practice
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practice, which is here seen in terms of Pinar’s fourth moment, synthesis, where past, present,
and hopeful intentions for the future come together. Chapter Seven turns to Sosnowska and
Zanko’s (2022) article, “Three Kairoi – Three Aions. Paul Tillich, Ultimate Concern and
Pedagogy of Radical Hope,” as a frame for situating the findings of this study within a larger
contemporary educational and historical context. The study ends with a postscript, Danny’s
Story, which reveals one student’s radical hope
Water-Assisted Flocculation of Fine Solids by Biopolymer Additives for the Purification of Solvent Extracted Bitumen
No full textMicroscopic fine solids suspended in non-aqueous bitumen extraction systems present a persistent challenge for phase separation and further upgrading/refining of bitumen. These solids, often partially coated with bitumen, exhibit heterogeneous wettability and strong interfacial activity, stabilizing water-in-oil emulsions and resisting traditional gravity-based separation. The aim of this thesis is to understand and evaluate water and water-assisted destabilization strategies for the efficient removal of these fine solids under varying chemical and thermal conditions, using natural biodegradable polymers.
This work systematically investigates the interfacial behavior of bitumen-coated fine solids and explores how water chemistry—including pH, temperature, and cation identity—influences that behavior when the fine solids are suspended in an organic solvent such as cyclohexane. Three biodegradable polymers—gum arabic (GA), dextran, and diethylaminoethyl-dextran (DEAE-d)—were selected as polymer flocculants for their structural diversity and environmental compatibility. Advanced interfacial techniques such as atomic force microscopy (AFM), quartz crystal microbalance with dissipation (QCM-D), interfacial tension measurements, and focused beam reflectance measurements (FBRM), were employed to assess adhesion behavior, aggregate formation, and surface adsorption dynamics.
Findings establish that DEAE-d, due to its amphiphilic and cationic nature, showed the strongest adhesion to bitumen-coated fine solids' surfaces, greatest interfacial adsorption, and most consistent reduction in both water and solid content in cyclohexane-diluted bitumen (dilbit). Performance was enhanced under alkaline pH (8.5–10.2), elevated temperatures (65°C), and in the presence of calcium ions (Ca²⁺) in the aqueous phase, highlighting the role of ionic bridging and electrostatic attraction. GA also displayed promising behavior, particularly in multivalent cation conditions, whereas dextran was largely ineffective due to its neutral, linear structure and limited interfacial activity.
A two-step flocculation protocol—comprising an initial polymer addition followed by rinsing with deionized (DI) water—was employed and evaluated against an optimized one-step treatment. This sequential strategy allowed controlled surface adsorption followed by floc consolidation, resulting in larger aggregate sizes, clearer supernatants, and more compact sediments. Additionally, the introduction of the second step of introducing water after polymer addition results in the removal of said polymer from the non-aqueous slurry, preventing any further problems downstream. These effects were confirmed via FBRM tracking, QCM-D analysis, and visual settling observations.
Overall, the results revealed that the integration of biodegradable polymers with water chemistry tuning and multi-stage flocculation significantly enhances the separation of fine solids from cyclohexane diluted bitumen. This work contributes new mechanistic insights into the interfacial destabilization of bi-wettable particles and offers scalable, environmentally responsible solutions for improving the efficiency and viability of nonaqueous extraction of bitumen from oil sands. The proposed strategies are compatible with solvent recovery processes and may be transferable to other colloidal systems involving surface-active particles
Development of Sustainable Cement-based Grouts with Enhanced Sealing and Thermal Performance for Borehole Heat Exchangers
No full textGround Source Heat Pump (GSHP) systems, which utilize shallow geothermal resources, are a reliable and renewable alternative to conventional space heating and cooling solutions due to their high efficiency and environmental benefits. Typical GSHP systems comprise a heat pump and a ground heat exchanger (GHE). Among GHE types, the vertical borehole heat exchanger (BHE) is widely preferred for its smaller spatial occupation and superior energy efficiency. In BHEs, grout plays a crucial role, functioning as both a sealant to preserve borehole integrity and a thermal conductor to facilitate heat exchange between the ground and pipes. Thus, selecting and applying appropriate grout is essential for the successful installation and operation of BHEs. Cement-based grout is the most used grout currently which is composed of ordinary Portland cement (OPC) and sand. However, because of the inherent characteristics of OPC, the current grout faces challenges of volumetric instability, limited thermal conductivity, and high carbon intensity, negatively affecting the sealing and thermal performance of the grout as well as the sustainability of BHEs. To address these issues, this study aims to develop novel sustainable cement-based grouts with enhanced sealing and thermal performance for BHE applications.
In this study, calcium sulfoaluminate (CSA) cement was first blended with OPC to mitigate its shrinkage. Then silica sand and graphite were incorporated into the grout to enhance its thermal conductivity. Furthermore, a green cement, limestone calcined clay cement (LC3), was used to develop the grout with low carbon footprints. Moreover, machine learning techniques were used to build the predictive model of the thermal conductivity of the grout, and numerical models were developed to evaluate the performance of BHE using the developed grout.
The results show that CSA cement effectively improved the volumetric stability of the cement-based grout. For instance, replacing OPC with 15% CSA cement and 15% gypsum reduced shrinkage of the grout to 0.018% at 28 days—approximately ten times lower than 100% OPC grout. Additionally, incorporating silica sand and graphite significantly enhanced the thermal conductivity of cement-based grout. Compared with the grout using river sand, the thermal conductivity of the grout using silica sand increased by 165% at oven-dry conditions under the same binder system. Adding 12% graphite further enhanced thermal conductivity by up to 313% under the same conditions. Utilizing LC3, the novel environment-friendly cement-based grouts were developed, which are composed of 90% LC3, 5% CSA cement, and 5% gypsum. The novel grouts achieved high thermal conductivity of 2.045–3.184 W/mK in saturated states, negligible shrinkage with a variation of -0.0091% to–0.0110%, and sufficient compressive strength of 26.04–35.24 MPa at 28 days. Meanwhile, they show up to 30% less energy consumption and 36% fewer emissions compared with traditional OPC-based grouts. Moreover, the backpropagation neural network (BPNN) model was selected as the optimal model for forecasting the thermal conductivity of cement-based grouts, achieving an R2 of 0.991—29.3% higher than the conventional model (i.e., Hashin-Shtrikman model). At last, the numerical study demonstrates that the developed grout can improve the short-term and long-term performance of BHE systems. For example, compared with the conventional grout, using developed grout results in a 12% increase in the total extracted heat during a 30-minute heating operation and improvements of 0.004 in coefficient of performance (COP) for heating and 0.5 in seasonal energy efficiency ratio (SEER) for cooling in a cooling-dominant scenario.
Overall, this study developed novel sustainable cement-based grouts with enhanced sealing and thermal performance for BHE applications under GSHP systems. The developed novel grouts can improve the efficiency and safety of BHEs while significantly mitigating environmental impacts, thereby promoting a more sustainable approach to harnessing shallow geothermal energy
Quality Assurance for Trustworthy AI-enabled Cyber-Physical System
No full textCyber-physical systems (CPSs) are integrated systems where software components and physical plants collaboratively accomplish challenging tasks. In light of such an advanced cyber-physical interaction scheme, CPSs have demonstrated advanced capabilities and have been deployed in a diverse spectrum of industrial applications, such as autonomous driving, robotics and power plants. Meanwhile, with the advancement in Artificial Intelligence (AI), AI models show performant abilities in a variety of downstream tasks (e.g., perception, planning and control). Hence, an increasing number of CPS applications are actively adapting AI components such as Deep Neural Networks (DNNs) and Large Language Models (LLMs) into their development and operation loops to empower existing capabilities and extend new functionalities. This type of new CPS, in which AI components, traditional software units, and physical plants are deeply intertwined, is called AI-enabled Cyber-physical Systems (AI-CPSs).
Despite the promising capabilities shown by AI-CPSs, the quality and trustworthiness of AI-CPS still remain concerns. Namely, there is still a lack of comprehensive understanding of the extent to which such a new AI-driven cyber-physical operation scheme can fulfill the functional requirements with no safety risks to human life and property loss. Moreover, most existing quality assurance techniques (e.g., testing, debugging, monitoring and repair) are specifically designed for AI models and traditional CPS, respectively, which may not still be effective in the context of data-driven AI-CPSs. Therefore, new methodologies and engineering supports are needed to assure the quality, safety, reliability and robustness of AI-CPSs in different applications across domains.
To tackle the aforementioned challenges, this dissertation first investigates the effectiveness of existing SE techniques in the context of AI-CPSs and then proposes new solutions to improve the trustworthiness of AI-CPSs across domains. To establish the foundation and playground for the following research, we first presented a public AI-CPS benchmark that encompasses CPSs from various industry domains and leverages Deep Reinforcement Learning (DRL) methods as control systems. We then conducted a systematic study of these AI-CPSs and their traditional counterparts to identify current challenges and future opportunities. We noticed that uncertainty and unreliability are the key challenges to trustworthy AI-CPSs, necessitating a powerful and realistic simulator as a development platform and a tailored testing tool. Thus, we developed a new AI-CPS development and testing framework based on a physics engine-based software simulator, which is more accurate, scalable, and flexible. Leveraging the benchmarks, we combined the modular redundancy concept from conventional CPSs with ensemble methods from AI. Thus, we propose SIEGE, a semantics-guided safety enhancement framework that improves the safety, efficiency, and robustness of AI-CPSs. Moreover, witnessing the promising capabilities demonstrated by LLMs, we developed a novel LLM framework for automated reward function design to facilitate the development of AI-CPSs with DRL agents. In summary, this dissertation makes contributions to the field of AI-enabled cyber-physical systems by (1) characterizing the challenges and opportunities of trustworthy AI-CPSs, (2) establishing the benchmarks and investigating the effectiveness of existing SE techniques in AI-CPSs, (3) proposing testing and enhancement methods to ensure the quality of AI-CPSs across different domains and (4) developing a new framework that leverages LLMs to facilitate the development of AI-CPSs. These contributions foster the understanding and advancement of quality assurance for AI-CPSs, paving the path towards trustworthy AI-CPSs in the era of data-driven AI
One Blue Health: Climate, Nutrition, and Community Health in Small-Scale Fisheries in Mexico
No full textClimate change is reshaping the dynamics of natural ecosystems, as well as interactions between and among humans and their environment. These changes are particularly evident in ocean ecosystems, which include impacts to the socio-cultural health and well-being of coastal and fishing communities. Through an interdisciplinary lens and in partnership with ocean-dependant fishing communities in Mexico, this research characterized the connections between ecological changes, social systems, and human nutrition in the context of climate change. To frame the research and guide our approach, we co-developed and operationalized a "One Blue Health" framework, which integrates principles from One Health and Planetary Health, to explore ocean-human relationships in the context of climate change.
The mobilization of our One Blue Health framework started with a scoping review to characterize the range, extent, and nature of literature about climate change impacts on nutrition, immunity, and infectious disease in North America. The review highlighted that, while many studies discussed these topics conceptually, few provided empirical insight into how climate change affects both nutrition and immunity in real-world settings. Therefore, we responded to this research gap with a place-based, multi-method qualitative research project that was grounded in the lived experiences of two small-scale fishing communities in Baja California, Mexico. Following a One Blue Health approach and in partnership with communities, we used an integrative qualitative approach to gather rich, descriptive data through daily-routine accompaniment methods, which involved shadowing participants to understand daily activities and interactions; open-ended interviews (n = 54), allowing community members to express their thoughts and lived experiences; and photo-elicitation techniques, engaging people through visual storytelling to foster discussion. People's narratives revealed climate-related disruptions to fishing livelihoods, reduced species availability, and unpredictable and harsh fishing conditions. Community members also shared how changes were contributing to dietary shifts away from traditional seafood and toward less nutritious alternatives, undermining food security and social well-being. People identified systemic barriers to effective climate adaptation, including infrastructure gaps, restrictive policies, and gender-based disparities. In the face of these challenges, community members reflected on key adaptation strategies, including local conservation initiatives, cooperative governance practices, and preservation of intergenerational ecological knowledge. Given the clear socio-cultural importance of seafood in these communities, we then looked at its nutritional contributions to diet. Using two quantitative dietary recall tools, we estimated nutrient intake from commonly consumed seafood species (n = 146 community members). The results demonstrated that several seafood species significantly contributed to meeting the nutritional requirements for immune-relevant micronutrients. Demographic disparities in consumption were also observed, reflecting socio-cultural differences in food access and dietary practices. To explore how community members might adapt to future climate-food risks, we used a qualitative scenario-based method, in which community members reflected on dietary choices during hypothetical climate shocks. Community members responses revealed expected declines in non-seafood and shellfish intake, but an increase in fish consumption. Finally, to understand how climate change could impact nutrition in these communities, we merged climate-ecological projections of future seafood catch potential with the dietary recall data collected in collaboration with the communities. This multi-methods approach allowed us to understand dietary consequences under two climate scenarios (Representative Concentration Pathways 2.6 and 8.5) for 2050 and 2100. Projections indicated significant declines in maximum catch potential for nutritionally important species, alongside habitat suitability shifts that suggest spatial redistributions or local extinctions of key fish and shellfish. We also found potential increase in other species that may represent adaptation opportunities for these fishing cooperatives and communities.
Taken together, this research advanced understanding of how climate change shapes health in ocean-dependent communities. It emphasized the interconnectedness of marine ecosystems, social systems, and human health, highlighting the importance and utility of a "One Blue Health" approach to research. This research also offered new tools and insights to inform the development of just, context-sensitive responses to climate-driven health challenges in coastal systems
YORUBA IMMIGRANT PARENTS' APPROACHES TO AUTONOMY SUPPORT
No full textParenting in immigrant families often involves navigating tensions between cultural continuity and adaptation, particularly when traditional values intersect with the norms of a new society. This study examines how Yoruba immigrant parents in Canada conceptualize and implement autonomy support in raising their adolescents. Using semi-structured interviews with six participants and reflexive thematic analysis, the research examines how parents balance Yoruba values, such as hierarchy, respect, and communal responsibility, with Canadian expectations for adolescent independence, voice, and open communication. The analysis draws on Self- Determination Theory, the Theory of Sociocultural Models, and Kagitçibaşi’s concept of the autonomous-related self to situate participants’ meaning-making processes within broader cultural and psychological frameworks. Four key themes emerged: (1) Cultural Anchors and Social Expectations, which explores how parents maintain Yoruba cultural and religious values while contending with shifting social norms; (2) Relational Foundations of Autonomy Support, highlighting the role of emotional closeness, communication, and mutual respect in supporting adolescent voice; (3) Fostering Autonomy with Boundaries, examining how autonomy is permitted within carefully defined limits shaped by safety, faith, and cultural expectations; and
(4) Parenting Between Two Worlds, which captures how parents negotiate cultural dissonance, rework traditions, and reconstruct authority in a new context. Findings suggest that Yoruba parents in the diaspora do not simply replicate traditional parenting or adopt Western norms wholesale, but rather engage in ongoing negotiation, creating hybrid parenting approaches that support adolescent autonomy while preserving cultural identity. This study contributes to cross- cultural parenting literature by offering a nuanced understanding of how autonomy support is enacted in African immigrant families and offers implications for culturally sensitive practice in psychology and education
(How) are Schools Safe?: A Critical Examination of School Safety Policies in Three Provinces
No full textBackground
Schools are expected to provide safe environments for learning and relationship-building; however, aggression in Canadian K–12 schools remains a persistent and under-recognized concern. School safety policies play a key role in shaping how aggression is understood and addressed. This study draws on critical discourse analysis to examine how policy language constructs notions of both “safety” and “threat.” Grounded in the view that texts shape social realities and identities, this approach highlights the ideological assumptions and power relations embedded in school safety discourse. The analysis situates contemporary policy within the historical use of zero-tolerance approaches, which emphasized uniform punishment without consideration of context, and contrasts these with more recent shifts toward progressive discipline. Evidence from Canadian schools suggests that restorative and relationship-based approaches are associated with reduced conflict and suspensions
Una Mehrotra - Abstract 35 - Innovate Conference 2025
No full textUsability evaluations assess whether an intervention meets its intended purpose and its users’ needs. Understanding how parents and children evaluate digital health interventions can inform user-centered designs and drive widespread adoption of interventions
Effah-Frimpong Kofi Jnr - Abstract 106 - Innovate Conference 2025
No full textAfrica has a large population living in rural communities which is served by a limited number of primary care nurses in this resource-limited setting. Nurses in Africa face a significant risk of burnout, characterized by physical and emotional exhaustion due to prolonged stress