Digital Commons Network^™

The Design And Synthesis Of New Materials Using Nucleophilic Aromatic Substitution Reactions, Lavneet Kaur, Kenneth E. Maly

Theses and Dissertations (Comprehensive)

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 …

Coupling Remote Sensing And Modelling To Monitor The Spatial Distribution And Trends Of Surface Temperature And Ice Thickness On Sub-Arctic Lakes, Gifty Attiah

Theses and Dissertations (Comprehensive)

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 …

The Impacts Of Permafrost Thaw Slumps On Arctic Stream Ecology, Maria Dolan

Theses and Dissertations (Comprehensive)

Climate change is intensifying permafrost thaw across terrain of the circumpolar Arctic. Increased temperatures and rainfall at northern latitudes have resulted in the expansion of thermokarst features such as retrogressive thaw slumps, which make previously frozen debris available for transport into nearby river systems. In the Peel Plateau, Northwest Territories, the mobilization of these materials exposes rivers to a large quantity of sediment and solutes that may act as a chronic, press disturbance, potentially altering stream food webs. Here, I examine if: 1) thaw slumps have driven changes to the physical and biological properties of slump impacted streams since an …

“People [Are] Not Dying Because Officers Aren't Following Their Training. ‘It's Because They Are.”: The Construction Of Police De-Escalation Of Individuals In Mental Health Crises In Canadian Media, Renée Haddock

Theses and Dissertations (Comprehensive)

Police are often assumed to be the "de facto" response to people in mental health crises. Contact between police and Canadians with mental illness and in crisis is routine and on the rise (Livingston, 2016). Police responses to these incidences have been criticized after several, highly publicized and tragic encounters between police and people in mental health crisis and the overrepresentation of people of colour in these instances. Media outlets determine which stories are prioritized, how they are framed, and which information to include or omit (Fawzi, 2018). Notably, public knowledge of police activities greatly impacts community perceptions of police …

Investigating The Thermal Stratification Patterns Of A Shallow Polymictic Boreal Shield Lake And The Effectiveness Of Models In Predicting Shallow Lake Thermal Profiles, Matthew Roberts

Theses and Dissertations (Comprehensive)

Thermal stratification is a core process of lakes which plays a critical role in shaping the ecological dynamics of lakes, influencing major processes like nutrient cycling and oxygen availability. For shallow polymictic lakes, thermal stratification patterns present some unique differences due to the complex and variable nature of these lakes. In this thesis, I examined thermal stratification in a shallow polymictic lake in northwestern Ontario during the ice-free season of 2019 to investigate the frequency, duration, and driving factors of thermal stratification. The lake underwent 146 separate stratification events, with a median duration of 2 hours per event, with a …

Lactate's Role In Appetite Suppression, Seth Mccarthy

Theses and Dissertations (Comprehensive)

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 …

Reversible Degradation Of Peptidoglycan By Lytic Transglycosylases, Aaron Devereaux

Theses and Dissertations (Comprehensive)

Antimicrobial resistance continues to be a burden on the global healthcare system with an estimated cost of billions of dollars and millions of deaths each year. Recently, there has been little to no development on new antibiotics to treat bacterial infection, and any that are developed become resisted to within a few years. Both Gram-positive and Gram-negative bacteria contain a mesh-like layer called peptidoglycan (PG) that surrounds their cells providing strength, cell shape, and protection from their environments. This layer is a polymer of N-acetylmuramic acid (MurNAc) and N-acetylglucosamine (GlcNAc) connected via a b-1,4-glycosidic bond, with each strand being cross-linked …

“It Is Tiny And It Is Everything”: Exploring The Effects Of Arts-Integrated Gardening On Experiences Of Ecological Grief Through Autoethnographic Research, Christina Kingsbury

Theses and Dissertations (Comprehensive)

This study explores how arts-integrated gardening affects experiences of ecological grief through autoethnography and draws on my personal experiences as a survivor of environmentally linked cancer and artist working with gardens through social practice. My research builds on two areas of emergent scholarship—investigations of ecological grief and gardens as sites for social work practice—to explore how social work may address ecological grief through arts-integrated gardening. I use a quilting autoethnography as a method of inquiry to foreground my subjective knowledge and analyze it through intersectional feminist, disability and decolonizing theories. By incorporating narrative analysis and arts-based inquiry—writing in place, poetic …

Exploring Mating Patterns: The Interplay Of Genes, Environment, And Their Evolutionary Outcomes, Sanduni Talagala

Theses and Dissertations (Comprehensive)

There is great variation in the reproductive tactics exhibited both between and within different species, which is reflected in how individuals engage in mate assessment, mate choice and offspring production. It is therefore important to understand general mating patterns of populations, the factors that influence these mating patterns, and the consequences they carry, in order to get a more holistic understanding of mating systems. This doctoral research represents a multi-pronged investigation of the factors shaping mating patterns and their consequences, how environmental factors influence mating patterns, and how both genotypes and the environment interact to influence mate choice decisions and …

Evaluation Of The Dnazyme Gr5 For The Determination Of Lead Speciation In Natural Waters, Gaganprit Gill

Theses and Dissertations (Comprehensive)

This thesis explores the development and application of a DNAzyme-based biosensor designed to detect labile metal species in environmental samples. Real time and on-site monitoring of labile metal fractions would make a valuable contribution to environmental management, as these fractions are the most bioavailable and pose significant toxicity risks to aquatic organisms. Conventional methods for detecting labile metals, while effective, are often burdened by high costs, complexity, and lengthy processing times, making them less ideal for rapid and widespread environmental assessments.

The first manuscript of this thesis (chapter 2) establishes the fundamental capabilities of the Pb²⁺-specific DNAzyme GR5 …

Quantifying Ecological Processes Predicting Barren-Ground Caribou (Ɂetthën; Rangifer Tarandus Groenlandicus) Occurrence Across A Heterogenous Northern Indigenous Protected And Conserved Area., Eric Jolin

Theses and Dissertations (Comprehensive)

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, …

Npr1 As A Temperature-Sensitive Regulator Of Pipecolic Acid-Mediated Plant Systemic Immunity, Spencer Tout

Theses and Dissertations (Comprehensive)

Healthy plant development requires balancing both abiotic (e.g. climate) and biotic (e.g. pathogen) challenges, which intercept important signaling pathways in plants. For example, climate change-associated elevated temperature can negatively modulate various aspects of plant immunity, including the production of central immune signals salicylic acid (SA) and N-hydroxypipecolic acid (NHP). Since SA and NHP signaling both require the master immune co-activator protein NON-EXPRESSOR OF PATHOGENESIS-RELATED GENES 1 (NPR1), it is important to investigate NPR1 as a potentially temperature-regulated molecular hub. Although the NPR1 gene is not transcriptionally downregulated at elevated temperatures (28° C vs. 23° C), little is known about …

Influence Of Temperature On Tfm Tolerance In Lake Sturgeon, Emily Bouffard

Theses and Dissertations (Comprehensive)

The lampricide, 3-trifluoromethyl-4-nitrophenol (TFM), has been used to successfully control invasive sea lamprey (Petromyzon marinus) in the Laurentian Great Lakes for over 50 years. TFM’s effectiveness is due to the relatively low capacity of sea lamprey to detoxify TFM. Water temperature has been shown to increase TFM tolerance in larval sea lamprey. However, the effects of temperature on TFM sensitivity in non-target species such as the endangered lake sturgeon (Acipenser fulvescens) are poorly understood, particularly during their early life stages. To determine how temperature affected TFM sensitivity, age 1-year-plus (1+) lake sturgeon acclimated to 8, 16, …

Grief On The Margins: The Death Of A Family Member To Substance Use, Adair Shaw

Theses and Dissertations (Comprehensive)

Despite Canada's high death rates from substance use, there is limited research on the sociopsychological impact on families, who often face stigma and disenfranchised grief. This study explores how family members make meaning of a substance-related death. Through qualitative inquiry, eleven family members were interviewed on their experience of grief from substance death. The imprint of losing a family member to mental illness and substance use is fraught with intergenerational grief, ambiguity, prolonged mental-emotional distress, and relationship challenges. Substance death was also associated with stigma, social withdrawal, and shame for many participants. However, grievers reconstructed the socially prescribed negative perceptions …

Impact Of Membrane Lipid Composition On The Structure And Function Of Uncoupling Proteins 1 And 2 From Arabidopsis Thaliana (Atucp1 And Atucp2), Elizabeth Silva

Theses and Dissertations (Comprehensive)

A proton gradient across the inner mitochondrial membrane (IMM) is required for the synthesis of adenosine triphosphate (ATP) via ATP synthase. In other words, generation of the proton gradient is coupled to the synthesis of ATP. Interestingly, uncoupling proteins (UCPs), also located in the IMM, dissipate the proton gradient, meaning that the gradient is not efficiently used for the production of ATP.¹ The mechanism of proton transport activity of UCPs has been hypothesized and widely debated for the past 20 years to also reduce oxidative stress by reducing the production of reactive oxygen species (ROS).² The majority of …

Lichen It: Optimizing Post-Fire Caribou Lichen Transplantation And Assessment, Elise Brown-Dussault

Theses and Dissertations (Comprehensive)

Caribou lichen species are common in mid- to late-seral boreal forests, serving as an important winter diet staple for boreal woodland caribou. However, as climate change causes boreal wildfires to increase in size, severity, and frequency, available tracts of mature forest are decreasing, diminishing the extent of mature caribou lichen stands. Caribou lichens reproduce vegetatively, so bigger and more severe fires could exacerbate their dispersal limitations, potentially extending the timeline for caribou lichen stand recovery beyond 80 years. Trials have shown that “transplanting” caribou lichen fragments into disturbed areas can lead to the establishment of caribou lichen mats; as such, …

Timing Of Migration And Seasonal Movements Of Arctic Grayling (Thymallus Arcticus) In Relation To Water Temperature In The Kakisa River And Upper Mackenzie River, Nwt: Results From An Acoustic Telemetry Study., Levi Snook

Theses and Dissertations (Comprehensive)

Arctic grayling (Thymallus arcticus) are a cold-water salmonid that inhabit waterbodies throughout the circumpolar regions of the northern hemisphere. In the last decade, Ka'a'gee Tu First Nation members as well as local sport fishers, have observed lower catches of Arctic grayling during their annual spawning run in the Kakisa River, NWT. Many potential causes of this decline have been hypothesized including climate change and over harvesting. Outside of the general annual spawning activity in the headwaters of the Kakisa River, the ecology of the population, including post-spawn habitat use and migratory patterns, remained understudied. To address these knowledge gaps, acoustic …

Using Landscape Ecology And Spatial Statistics To Examine The Impacts Of Proposed Removals To Natural Heritage System And The Agricultural System Of Ontario’S Greenbelt, Brianna Downey

Theses and Dissertations (Comprehensive)

The 2022 proposed removals from the Greater Toronto Area (GTA), Southern Ontario’s Greenbelt would have resulted in negative impacts including, reductions to the size and functionality of the Agricultural System and Natural Heritage System, which are components of protected Greenbelt area. Several removal sites were located either on or in close proximity to corridor areas of the NHS, reducing connectivity and negatively impacting the surrounding ecological area. The removal of Agricultural land primarily consisted of corn and soybeans, as well as large removals of woodland, wetland, and shrubland class areas. The removal sites on local Agricultural composition and configuration were …

Characterizing The Targeting Of Toc159 Receptors To The Chloroplast Outer Envelope Membrane And Their Role In The Assembly Of Distinct Toc Complexes, Michael Fish

Theses and Dissertations (Comprehensive)

Global agriculture and food security face challenges from climate change, population growth, and other human-driven pressures. Enhancing our understanding of plant biology, particularly chloroplast function, is critical for improving crop yield and stress resilience. As the sites of photosynthesis and key regulators of plant responses to environmental cues, chloroplasts depend on the precise import of thousands of nuclear-encoded proteins to maintain their biogenesis and function. While much is known about the core translocon components in the chloroplast outer envelope membrane that form the TOC complex, the mechanisms underlying their targeting, assembly, and regulation remain incompletely understood.

Plastids, including chloroplasts, evolved …

“We’Re Here, We’Re Queer, And We’Re Not Going Away” Student Policies And Lgbtq+ Students’ Experiences On Canadian Christian Campuses, Angela E. Gallo

Theses and Dissertations (Comprehensive)

Research highlights that Christian campuses are often unwelcoming and hostile spaces for lesbian, gay, bisexual, transgender, queer, and other gender and sexually diverse (LGBTQ+) students. Yet, research, including emerging Canadian research, often overlooks how institutional policies shape LGBTQ+ students’ experiences. Further, little attention is given to the affirming experiences LGBTQ+ students encounter on Christian campuses. Through a collective case study of two Canadian Christian universities involving document analysis and interviews, I explored the discourses that school policies constructed concerning gender and sexuality, LGBTQ+ students’ experiences of exclusion and affirmation, and how policy, alongside other factors, shapes their experiences and well-being. …

Development Of A Stress Response Framework For Understanding Sogie Refugee Health, Arooran Saravanan Ananthavel Murugan

Theses and Dissertations (Comprehensive)

As an increasing number of individuals flee persecution on the basis of sexual orientation and gender identity expression (SOGIE), Canada has become a prominent destination for SOGIE refugees. The chronic stressors encountered by this marginalized population remain insufficiently studied, particularly in relation to physical health outcomes. This qualitative study investigates the cumulative health impacts of chronic stress among SOGIE refugees through the application of a cell-to-society framework, underpinned by Minority Stress Theory (MST). The study seeks to develop a SOGIE-specific stress response framework that theorizes the processes by which social and environmental stressors become biologically embedded, thereby contributing to elevated …

Limiting H1n1 Replication Via The Dsrnai Pathway Using Sequence-Specific Ldsrna, Shawn Marie Sharon Carr, Stephanie Dewitte-Orr

Theses and Dissertations (Comprehensive)

The seasonal influenza virus causes a common respiratory illness that can be life threatening to the immunocompromised, the very young, and the elderly. The current strategies for avoiding a serious influenza virus infection are good hygiene practices and the annual influenza vaccine. Unfortunately, last year’s influenza virus vaccine effectiveness ranged between 32-60% for children and adolescents and 46-54% for adults. These low efficacy rates are due to the vaccine often targeting hemagglutinin, a highly variable surface protein. This thesis seeks to create a prophylactic treatment via the RNA interference (RNAi) response that targets the virus’s conserved genes that are integral …

Immune Pathway Modulation In Melanoma Using Chitosan Nanoparticle-Mediated Dsrna Delivery, Bethel C. Iwuji

Theses and Dissertations (Comprehensive)

Cancer is a group of diseases characterized by abnormal and uncontrolled cell division, which typically results in the formation of tumours. Even with advances in treatments, cancer remains one of the leading causes of death globally. Melanoma is an aggressive form of skin cancer which is highly malignant, develops in the pigment-producing cells of the skin, melanocytes, and in the late stages of the disease poses a significant challenge for therapeutic intervention due to its multidrug resistance. The innate immune system is the first line of defence against invading pathogens, including viruses, bacteria, and fungi, and can recognize and destroy …

Comprehensive Analysis Of Environmental Particulate Matter: Chemical Composition And Microbial Assessment, Uyen T. L. Le

Theses and Dissertations (Comprehensive)

Rapid industrialization and population growth have contributed to a decline in air quality, with particulate matter (PM) posing particular concern. PM originates from both natural and human sources and often contains toxic chemicals and microorganisms, including potential pathogens. Inhalation of PM is linked to respiratory and cardiovascular diseases, underscoring the need to characterize better its chemical and biological composition in understudied region - Waterloo, Ontario, Canada. The present thesis is a culmination of three main parts. Part 1 will describe the use of the dithiothreitol (DTT) assay to quantify the oxidative potential of PM through DTT consumption of redox-active field …

2slgbtq+ Contact As A Vehicle For Promoting Alternative Sexual Scripts Through Exposure To Queer And Trans Ways Of Knowing, Sophie R. Landry

Theses and Dissertations (Comprehensive)

Research on the Traditional Sexual Script (TSS) suggests it can have harmful repercussions, such as sexual violence, gender inequity, and the undermining of communication. My research explores the novel idea that intergroup contact with 2SLGBTQ+ individuals can promote CisHet (cisgender, heterosexual) individuals to value alternative sexual scripts that emphasize communication, authenticity, and equity, and to question the TSS. In Study 1, I found that CisHet people who had more 2SLGBTQ+ contact reported greater concern for consent and were less likely to agree with traditional gender norms relative to those who made less contact. In both Study 2 and Study 3, …

Integrating Indigenous Values And Community Strengths To Achieve Indigenous Food Sovereignty And Community Well-Being In The Ka’A’Gee Tu First Nation, Northwest Territories, Jennifer K. Temmer

Theses and Dissertations (Comprehensive)

Northern Indigenous communities face disproportionate impacts from interconnected challenges related to climate change, food security, health, and cultural preservation, that threaten traditional food systems and practices. While there is a growing recognition of the importance of community-driven solutions, existing frameworks fail to integrate Indigenous values and local priorities effectively. This research addresses this gap by exploring how the Ka’a’gee Tu First Nation (KTFN) is responding to these crises through climate change adaptation efforts focused on food system sustainability as a pathway to self-sufficiency and community well-being. To contribute to these efforts, this dissertation uses Participatory Action Research to facilitate community-driven …

Inductions Of Long-Term Potentiation With Biomimetic Electromagnetic Fields In Primary Neurons, Cooper E. Kansala

Theses and Dissertations (Comprehensive)

Endogenous brain rhythms guide neural communication and plasticity, raising the question of whether weak, temporally structured electromagnetic fields (EMFs) that mimic these rhythms can modulate neuronal activity in a targeted, biomimetic manner. This thesis investigates whether patterned EMFs designed to reflect the temporal structure of hippocampal long-term potentiation (LTP) are more effective at inducing neural plasticity than conventional sinusoidal fields or no stimulation at all. Cortical neurons cultured from postnatal rats were exposed to patterned EMFs for 30 minutes and assessed across three distinct experimental domains. In Chapter 2, microelectrode array (MEA) recordings revealed that the LTP-patterned field significantly increased …

The Body’S “Why?”: Therapists’ Embodied Approaches To Meaning-Making In Trauma And Complex Ptsd, Tanya D. Rock

Theses and Dissertations (Comprehensive)

The challenge of finding meaning in trauma is one that has inspired conversations in psychotherapeutic circles as well as amongst theologians and philosophers. Finding meaning following trauma has been positively associated with growth following the traumatic incident and has been labelled as critical to the progression of healing (Herman, 1992). This study aims to examine the role therapists play in meaning-making with clients who have experienced trauma. The research question is “how do therapists handle meaning of life challenges with traumatized clients?” Ten experienced therapists participated in this qualitative, phenomenological study. Key findings included common therapist responses to client’s “why?” …

Functional Design Of Dissymmetric Ligands For Coordination Systems, Kaitlyn R. Brown

Theses and Dissertations (Comprehensive)

Herein, the functional design of dissymmetric ligands for coordination systems is explored with a focus on their synthesis and structural characterization. The design strategy of these ligands incorporates the ability to coordinate both metal cations and anions along with a ligand site for other functionalization. Their synthesis, structural and other characterization, Hirshfeld surface analysis, and some metal-coordinated complexes are discussed. Chapter 1 introduces supramolecular and coordination chemistry, along with relevant literature that supports this research and outlines the thesis objective. Chapter 2 investigates the hydrogen bonding of a dissymmetric pyrimidine thioether ligand in its neutral form, water solvate, protonated nitrate …

The Experiences Of Mothering With An Intimate Partner Violence-Related Brain Injury, Emily L. Sebben Miss

Theses and Dissertations (Comprehensive)

One in three Canadian women will experience intimate partner violence (IPV) in their lifetime, and 75% of them have a probable brain injury (BI) (Haag et al., 2022). Despite the recent growth of IPV-BI research, many survivors remain undiagnosed and many aspects remain unexplored. The experiences of being a mother with an IPV-related BI has been left untold. These gaps leave frontline workers with little guidance in supporting survivors who are specifically mothers. This research reports on a qualitative study exploring the lived experiences of mothering with an IPV-BI. The study uses a constructivist worldview and hermeneutic phenomenology to amplify …