Coupling Remote Sensing and Modelling to Monitor the Spatial Distribution and Trends of Surface Temperature and Ice Thickness on Sub-Arctic Lakes

Lake surface temperature (LST), lake ice thickness (LIT), and lake ice phenology (LIP) play significant roles in the diverse regional processes of freshwater in cold regions. They offer direct indications of regional weather and climate conditions, and their interactions with the atmosphere impact climate processes. Furthermore, lake ice is valuable to northern communities, such as those in the Northwest Territories (NWT). Ice roads, including the longest ice road in the NWT, spanning over 80 lakes, are constructed during winter to haul goods to and from industrial establishments (e.g., mines) and for travel within and between communities. A significant challenge to lakes and the ongoing use of ice roads are the changes in LST, LIT and LIP due to climate warming. Knowledge of LST, LIT, and LIP is crucial to understanding how lakes respond to climate change and determining how much weight an ice cover can safely sustain for winter travel on frozen lakes. This knowledge, however, is minimal due to the logistical difficulties in traditionally collecting measurements directly. In recent years, satellite-based observations have gained significant traction for studying lakes. However, multispectral sensors are not equipped to measure ice thickness directly, as it is a subsurface feature, which poses a limitation. Furthermore, other methods, such as one-dimensional thermodynamic lake ice models, which rely on weather station input data, are limited by the sparse availability of weather station and in-situ data, especially at high latitudes. This research adopts a multimodal monitoring approach to address these limitations by combining remote sensing data with spatially distributed modelling to study and monitor the trends and spatial distribution of LST, LIT and LIP. In this study, a retrieval algorithm was applied to the thermal bands of Landsat archives to generate a lake-specific surface temperature dataset (North Slave LST dataset) for 535 lakes in the North Slave Region (NSR), NWT, Canada, from 1984 to 2021. Cloud masks were applied to Landsat images to eliminate cloud cover. In addition, a 100 m inward buffer was used on lakes to prevent pixel mixing with shorelines. A good agreement was observed between in-situ observations and North Slave LST, with a mean bias of 0.12 °C and a root mean squared deviation (RMSD) of 1.7 °C. The North Slave LST dataset contains more available data for warmer months (May to September; 57.3 %) than colder months (October to April). The North Slave LST dataset is available at https://doi.org/10.5683/SP3/J4GMC2 (Attiah et al., 2022). Based on the North Slave LST data, LST trends and spatial distribution across the 535 predominantly small to medium lakes across NSR were studied. LST was analyzed in four distinct periods: open water season (OW), ice cover season (IC), and the transitional months of May (TM) and October (TO). The trend and relationships of LST were analyzed using the Mann-Kendall test and a multilinear regression model. The analysis revealed an overall increase in LST, with average rates (max) of 0.03 °C/year (0.05 °C/year), 0.03 °C/year (0.06 °C/year), and 0.13 °C/year (0.27 °C/year) for OW, TM, and TO, respectively across study lakes. A faster rate of change was observed in October compared to other periods. Using the North Slave LST data generated as input, a comprehensive approach was adopted to simulate the spatial variability of ice thickness on lakes at a high resolution by spatially distributing a one-dimensional thermodynamic lake ice model. The spatial distribution of LIT was modelled for study lakes from 1984 to 2022. The generated LST data, in combination with the European Centre for Medium-Range Weather Forecasts (ECMWF) Reanalysis v5 (ERA5) data, were used as inputs for the model. The model simulates the spatial distribution of daily lake ice thickness on a 50-meter spatial grid as well as the annual freeze-up and break-up dates. Results showed a root mean square deviation of LIT from 2.7 cm to 7 cm compared to in-situ data. Further analysis of ice cover on study lakes from 1984 to 2022 revealed decreasing trends in LIT (-0.26 cm/year to -0.10 cm/year) and ice cover duration (ICD) (-0.40 day/year to -0.15 day/year). Simulated LIT and freeze-up proved sensitive to morphometry (depth), while location properties (latitude/longitude) primarily drove the break-up process. This dissertation provides comprehensive approaches to deriving LST, LIT, and LIP information from small and medium lakes in data-sparse regions. A multimodal approach combining remote sensing and spatially distributed modelling is adopted to address the insufficiency of in-situ data and the sparse distribution of weather station data. The methods utilized can be replicated in other regions, providing a broader understanding of the trends and spatial distribution of LST, LIT, and LIP on sub-arctic lakes with varying physical, geographical, and morphometrical properties

The Impact of COVID-19 Pandemic Demands on By-law Officer Wellness and Work

This research sheds light on how the rapid demand to enforce transitioning pandemic-related (and reopening) mandates impacts the wellness of bylaw officers in the context of resource strain. Ontario bylaw officers are at the forefront of the province’s response, enforcing lockdown rules to ensure community safety. This research is imperative in understanding how bylaw officers maintain their roles in municipal enforcement, while enforcing rapidly shifting COVID-19 regulations and moving forward into a post-lockdown climate. The research focuses on identifying and understanding the demands and resources that currently typify bylaw officers working in Southern Ontario. It further examines how the COVID-19 pandemic influences the level of work commitment and engagement bylaw officers have towards their jobs. Guided by Bakker and Demerouti’s (2007) Job Demands and Resource Model (JD-R Model), which suggests that an imbalance between high demands and limited resources can lead to stress and strain, this study explores the specific job demands and resources available to Ontario bylaw officers. In using a qualitative approach to data collection and analysis, semi-structured interviews with consenting bylaw officer participants (N=8) have been conducted. The data explores the lived experiences of bylaw officers during the announcement of the Emergency Act, understanding how work demands and resources impact their mental well-being, job engagement, and commitment. This study addresses a gap in the literature by investigating bylaw officers, and it clarifies the unique demands, stressors, resources, coping well-being, and occupational performance factors that have influenced their work during the COVID-19 pandemic and post-pandemic. Moreover, the study highlights the challenges they face, such as increased job demands, insufficient resources and the emotional toll of enforcing public health measures. Additionally, it identifies coping strategies used by bylaw officers, including peer support, mental health resources, and personal coping mechanisms

Pathways to Sustainable Employment: Bridging Community Justice and Social Enterprise Programs for Criminalized Women

Within the context of the Canadian criminal justice system, women face significant challenges when striving to secure and retain employment due to structural stigma and punitive practices. These challenges form barriers to accessing employment programs or sustainable career paths. To explore these barriers, a qualitative research study including semi-structured interviews and focus groups incorporating an arts-based project was conducted with fourteen women who navigate such obstacles. The arts-based experience mapping exercise served as a foundational generative method to magnify the women’s experiences and validated the transformative contribution of arts-based methods to research processes. Through examination of the intersections established between community-based justice organizations and social entrepreneurship programs, the participants determined how bridging these systems together can support criminalized women to attain sustainable economic security. The constructivist grounded theory analysis reinforced an urgent need for the justice sector to shift from existing institutional-based employment program models to sustainable community-based configurations. The findings from this analysis informed the author’s creation of the Comoptigen Theory and Program Implementation Framework, which provides principles and program components for guiding the creation of a bridged employment program for criminalized women. This study advances the discourses about how restorative trauma-informed approaches and community-based justice development initiatives can contribute to strengthening the social economy in Ontario. Further outcomes of the research include concrete recommendations and practices for how community justice non-profit organizations can deliver employment programs integrating trauma-informed models of collective care

The Design and Synthesis of New Materials using Nucleophilic Aromatic Substitution Reactions

Abstract The overall objective of this research was to synthesize and study the structure-property relationships of novel polycyclic aromatic compounds capable of producing open crystalline networks based on π-stacking interactions in solid state. In this work, we describe a method of producing polycyclic aromatic compounds bearing electron-rich and electron-poor rings in order to promote cofacial π-stacking in the solid state. These compounds were synthesized from easily accessible molecules using nucleophilic aromatic substitution and copper-catalyzed aryl amination. The scope of phenoxazines bearing N-aryl substituents was explored for the synthesis of various polycyclic aromatic compounds. Interesting characteristics such as luminescence and predictable solid-state packing are displayed by electron-deficient phenoxazines. A focus was placed upon tuning the properties of the compounds by attaching phenoxazine units to different molecular architectures with the goal of producing open crystalline networks based on π-stacking interactions. The orange-colored solid compound 30 N-(4-bromophenyl) di-fluoro-di-cyano-phenoxazine was synthesized. Suzuki cross-coupling was used to attach an additional phenyl ring to compound 30 to produce compound 31. Similarly, compound 32 was synthesized by the reaction of 1, 4- benzenediboronic acid with two equivalents of compound 30. The crystal structure of compound 31revealed the presence of π-stacking interactions between the phenoxazine rings. The synthetic approach was extended to the preparation of heteropentacenes such as 52 and 58. Compound 52, which bears long alkyl chains, showed evidence of liquid crystallinity by polarized optical microscopy. However, the N-aryl heteropentacenes also showed limited stability

Lactate\u27s Role in Appetite Suppression

Once considered metabolic waste produced during exercise, lactate is now known to have diverse roles in biology. Muscle-derived lactate can travel through the bloodstream and be taken up by other tissues and i) oxidized, ii) converted to glucose via gluconeogenesis, or iii) bind to its receptor to trigger molecular signaling cascades. Lactate has been described as a “myokine” capable of inter-organ crosstalk and compelling evidence demonstrates lactate’s role as a signalling molecule in pathways related to the regulation of appetite. The purpose of this dissertation was to further elucidate lactate’s role in appetite regulation using series of studies aimed at manipulating lactate concentrations while attempting to minimize other extraneous factors that could influence appetite regulation. The main findings of this dissertation include: 1) oral sodium lactate ingestion does not increase blood lactate concentrations and is not an effective way to assess lactate’s effects on metabolism (Study #1); 2) using human studies with exercise intensity or a different exercise modality (resistance training) demonstrated exercise-induced lactate accumulation coincides with reductions in acylated ghrelin (Studies #2 & #3); 3) using a systematic review of all available work on exercise-induced lactate accumulation and post-exercise acylated ghrelin concentrations, statistical synthesis demonstrates an association between lactate and the acylated ghrelin (Study #4); 4) blood lactate accumulation following exercise does not alter the appetite regulating neuropeptides (or that peripheral blood samples do not reflect the central concentrations) (study #5); and finally 5) lactate accumulation due to exercise, injection, or oxamate administration (lactate dehydrogenase inhibitor) in a mouse-model does not alter the signaling cascades involved in appetite regulation. Overall, the results of this dissertation have improved our understanding of lactate’s role in appetite regulation and will guide future research necessary to fully elucidate the involvement of lactate in appetite-regulation

Quantifying Ecological Processes Predicting Barren-Ground Caribou (Ɂetthën; Rangifer tarandus groenlandicus) Occurrence Across a Heterogenous Northern Indigenous Protected and Conserved Area.

Northern ecosystems are experiencing a period of rapid and unprecedented change, with implications for species distributions, mammal community dynamics, and habitat associations. Understanding the ecological processes that shape species distributions is crucial for developing effective conservation strategies that can adapt to such change. This study examines drivers of barren-ground caribou occurrence, a species of cultural and ecological significance, across Thaıdene Nëné Indigenous Protected Area, an ecologically intact landscape of high habitat heterogeneity straddling the treeline of the Northwest Territories. I use spatial and temporal variation in caribou detections generated by camera traps to test the relative importance of apparent competition, top-down, or bottom-up ecological processes across biologically relevant seasons and areas of varying environmental heterogeneity. This is accomplished by regressing weekly detections of caribou against habitat covariates and/or the occurrence of heterospecific ungulates and their shared predators using generalized linear mixed models, each representing a specific ecological process and scale. As predicted, my results suggest this is a primarily bottom-up driven system. Caribou were negatively associated with taiga-type landcovers across all seasons regionally and showed more varied habitat associations locally. I found evidence for a localized seasonal shift in the relative importance of ecological processes, where top-down pressures exerted by gray wolves were the dominant driver of winter caribou occurrence. The hypothesis-based models used in this study failed to adequately explain spring caribou occurrence at the local spatial extent, suggesting unmeasured or no ecological processes govern caribou detections at that spatiotemporal scale. Future work could consider traditional knowledge and additional ecological variables (e.g., movement facilitation, insect harassment) to further refine spatiotemporal models of caribou occurrence. Effective caribou stewardship must be adaptive and context-sensitive, identifying when and where key ecological processes exert the strongest influence on the species. By determining the contexts in which bottom-up and top-down processes dominate across different spatiotemporal scales, this research can help inform management strategies within Thaıdene Nëné and contribute to broader ecological theory regarding the drivers of species distributions

Art/Place Making in a Settler Colonial Context: A Critical Place Inquiry on the Haldimand Tract/Kitchener-Waterloo From a White Settler Perspective

Although critical place scholars implicate artists in settler colonial processes of placemaking, there is little information on how white settler artists (WSAs) might use their creative practice to support practices of accountability and solidarity with Indigenous resurgence. This research responds to this gap by investigating the creative practices of WSAs located on the Haldimand Tract/in Kitchener-Waterloo (KW), and how they might approach critical, contextual practices in their creative work. A critical place inquiry was combined with ethnographic research principles and a transformative critical research paradigm. Six WSAs participated in mobile interviews, which took place in a location significant to them. To locate myself, I engaged in critical listening positionality after each interview, generating a soundscape, photos, and written reflections. Through qualitative analysis, key findings emerged including: moving towards practices of accountability in creative practice as WSAs, moving towards practices of solidarity with Indigenous resurgence in creative practice as WSAs, and creative practice is relational: situating self, relationship with others, land, place, and systems of settler colonialism. Findings indicate that WSAs creative practice can support practices of accountability and solidarity with Indigenous resurgence, however methodological and practical movement building is needed

HEAVEN IS QUIET AND TECHNOLOGIES ARE EVERYWHERE: CHINESE COSMOTECHNICS AND DYADIC APPROACHES TO INTERNATIONAL STRUCTURE

What constitutes the “practical” nowadays and how is it to be assessed? Can the concept of cosmotechnics, how technologies align with broader cosmic goals, be refined by recourse to Chinese traditions? In responding to these questions, I argue for a relational approach that considers technology and practical thinking, or techno-praxis, as a lens for interpreting political affairs. Drawing from philosopher Yuk Hui’s concept of cosmotechnics and the Neo-Confucian ti-yong (essence – function) dyad, a framework is proposed that synthesizes the technological and practical (qi-yong) in a dyad of its own. This dyad aims to provide a diagnostic cosmopolitics by focusing on notions of practicality and power, which are also reshaped by changes in dominant cosmotechnics. While qi-yong and techno-praxis form the primary dyadic center of this framework, how and in what fashion they relate are the other major theoretical foci of the dissertation. This involves making explicit the patterning of technical activities as an analytical space, and as part of general theorizations of patterning and their significance. Drawing on Gregory Bateson’s theory of cultural contact and schismogenesis, I conceptualize “dyadic patterning” as to how dyads are shaped through polarities of activity. Whereas common-sense understandings of politics primarily center the relational sensibilities of political groupings or state actors, techno-praxis as a dyad shifts towards the relation between technics/technicians/administrators and practices of power negotiation, with dyadic patterns between them at times reciprocally generative, symmetrically competitive, openly complementary, highly distanced, lopsidedly consuming, etc. This theoretical and genealogical construction of qi-yong/technopraxis culminates in two case studies, studying: (1) the patterned relations of technics and practices via readings of Chinese IR theorists, and (2) CCP approaches to technology under Deng Xiaoping and Xi Jinping. These cases also attempt to bring Yuk Hui’s cosmotechnics into conversation with IR and the political practicalities of elite power. Following Yuk Hui’s contention that the ti-yong dyad of “Western science, Chinese culture” forwarded after the Opium Wars remains dominant, there remains a desperate need for responding to how technics and technologies are integrated with human activities and practices, with practices of power being the focus of this project. In so doing, I hope to not transcend (or discard) binaries like East/West, mind-body, or techno-praxis, but to seek the variety of possible relations and how their changing patterns can be constructively engaged from within

Moral Identity: From Theory to Research

Moral identity, often defined as the importance or centrality of moral values to a person’s sense of self, has long been understood to play an important role in moral functioning. However, critical gaps remain regarding its development, cross-context stability, and behavioural significance. This dissertation addresses these gaps in three empirical studies, providing new insights into the nature and function of moral identity across the lifespan and in daily life. The first study (Chapter 2) explores developmental trends in moral identity, testing predictions from moral identity goal theory (Krettenauer, 2022). Using a cross-sectional sample spanning adolescence to old age, the study finds that with age moral identity becomes increasingly informed by abstractly rather than concretely construed values, and increasingly underwritten by internal rather than external motivation. The second study (Chapter 3) examines the stability and malleability of moral identity using experience sampling methods (ESM). By tracking momentary fluctuations in moral identity salience in a sample of Canadian university students over the course of a week, the study demonstrates that moral identity varies significantly within individuals across contexts while also showing stable between-person differences. Further, it shows that within- and between-person differences are related to a variety of morally relevant events experienced in everyday life. The third study (Chapter 4) also employs ESM to explore how moral and immoral action undertaken in daily life can be independently predicted by both within-person fluctuations and between-person differences in the salience and motivation of moral identity. It finds that while variation at both of these levels in moral identity is predictive of discrete actions and behavioural dispositions, this relation is more consistently found and stronger at the within-person level. Moral identity motivations are also found to be uniquely predictive of behaviour, in context-dependent ways. Together, these studies provide a comprehensive view of moral identity as a dynamic construct that develops over the lifespan, exhibits trait-like stability while also responding to situational factors, and profoundly influences behavior. By bridging developmental, socio-cognitive, and individual difference perspectives, this research contributes to a more nuanced understanding of moral identity

Shared Reading of Dual Language Books Within Urdu Speaking Families: An Analysis of Code-switching in Urdu and English Languages During Reading Interactions

Abstract Code-switching is common during bilingual conversation, and it is also inevitable in bilingual children. The occurrence of English code-switching during the conversation of Urdu-speaking families is established but has not been thoroughly researched. While the benefits of shared book reading are well-researched, shared book reading in dual-language storybooks is a novel approach. It has not been extensively explored with parents in home settings. Dual language books, or bilingual books, convey the same story in two languages. Typically, the entire book presents the text in both languages side by side (Domke, 2023). This study seeks to fill this gap by investigating code-switching in Pakistani Urdu-speaking households with 4-6-year-old children during shared reading of dual-language storybooks in English and Urdu in two locations, Canada and Pakistan. Thirty parent-child dyads from each country participated in reading sessions for three selected books. The research employed a mixed-methods approach, primarily utilizing three storybooks read by parents to their children. It aimed to understand the dynamics of bilingual interactions and code-switching through the lens of shared reading experiences. The results revealed significant effects of the story\u27s language on language production. More code-switching into English occurred when parents read the book in Urdu. In contrast, parents often switched to Urdu while reading in English. In Pakistan, linguistic behaviour revealed frequent use of English words or switching back to English from Urdu when parents explained the story in Urdu. The most common form of code-switching was inter-sentential switching into English. However, no significant differences were observed in parents\u27 overall language behaviour across the two locations. Interestingly, children in Pakistan frequently requested to listen to the stories in English, reflecting a preference for the school language. In contrast, half of the children in Canada preferred the story in Urdu, demonstrating pride in their heritage language. These findings align with the research of McCarthy (2018) and Muysken et al. (1996), emphasizing the influence of social context and educational language on bilingual families\u27 language practices