The Dynamic Relationship Between Permafrost And Landcover In Northwestern Canada’S Discontinuous Permafrost Zone, Olivia Carpino

Theses and Dissertations (Comprehensive)

Northwestern Canada’s subarctic is among the most impacted regions in the world as it is experiencing rapid climatic and environmental change. As a result, northwestern Canada has been experiencing region-wide permafrost thaw and disappearance, both of which are also occurring at unprecedented rates. Permafrost temperatures in the Taiga Plains have been warming steadily over the last several decades, which has been particularly detrimental across its lower latitudes of the discontinuous permafrost zone where the permafrost is already relatively thin and warm. These factors indicate that permafrost in the southern Taiga Plains may be in a state of disequilibrium with the …

Spatial And Temporal Characteristics Of Historical Surface Climate Over The Northwest Territories, Canada, Bhaleka D. Persaud

Theses and Dissertations (Comprehensive)

Climate change is putting many of the Northwest Territories (NWT) ecosystems, its people and animal populations at risk due to accelerated warming, permafrost thaw, and changing precipitation regimes. As the NWT continues to warm, at disproportionately higher rates when compared to the rest of Canada, threats to the stability of NWT’s ecosystems are expected to increase. Consequently, understanding how climate warming has changed historically and its implications on natural ecosystems requires point-to-region-specific, long-term climatic data to elucidate important drivers of observed changes relevant to decision makers at community, Indigenous, Territorial and Federal government levels. However, in situ climate data are …

Properties Of (Claw, 4k₁, Bridge)-Free Graphs, Taite Lagrange

Theses and Dissertations (Comprehensive)

Given a set H of graphs, a graph G is H-free if it does not contain any graph in H as an induced subgraph. The complexity of the colouring problem is known when H is a set of graphs on four vertices, with three exceptions. One of those exceptions is the case of {claw, 4K₁}-free graphs, for which our classes of {claw, 4K₁, bridge}-free and {claw, 4K₁, bridge,C₄-twin}-free graphs are subclasses.

The original goal of this work was to prove that {claw, 4K₁, …

Opposite Trees, Theo Goossens

Theses and Dissertations (Comprehensive)

A spanning tree of a graph G is a connected acyclic subgraph of G that includes all of the vertices in G. The degree of a vertex is the number of edges incident to that vertex. Given a spanning tree T of a graph G, an opposite tree of T is a spanning tree of G where the degree of each of its vertices is different from its degree in T. For complete, complete bipartite, and complete multipartite graphs, we give the conditions spanning trees of these graphs must satisfy in order to have an opposite tree.

Employees’ Reactions To Their Supervisors’ (Lack Of) Discretionary Adjustments In Performance Evaluations, Joanna Andrejkow

Theses and Dissertations (Comprehensive)

The purpose of my dissertation is to investigate how employees react to their supervisors’ decisions not to use ex-post discretionary adjustments to mitigate the effects that negative unexpected events have on their bonuses. To address this objective, I pose the following research question: Will the level of interdependence inherent within the compensation of multiple employees (i.e., compensation interdependence) and the likelihood the event will reoccur (i.e., future event likelihood) affect employees’ reactions (future effort and workplace deviance) when they don’t receive ex-post discretionary adjustments to mitigate the effects of negative events?

I address my research question using an experiment where …

The Power Of Dissent: Mitigating False Polarization And Cross-Party Dislike In Online Interactions, Victoria Parker

Theses and Dissertations (Comprehensive)

While actual polarization is on the rise in the United States, perceived polarization (i.e., false polarization) is growing at an even faster rate, contributing to increased cross-party hostility. A meaningful amount of out-party dislike may be produced by partisans’ dramatic overestimates of the prevalence of extreme, undesirable views among political opponents. In the current research, we examine whether exposing people to out-party dissenters who challenge their copartisans’ extreme views might help reduce people’s misperceptions of their opponents’ extreme views, and possibly mitigate animosity. Across five studies (N = 3789), we explore how seeing public ingroup dissent (in the form of …

The Effect Of Alkalinity On Lampricide Effectiveness And Gill Physiology In Invasive Sea Lamprey (Petromyzon Marinus), Alexandre J. Walsh

Theses and Dissertations (Comprehensive)

The pesticides, 3-trifluoromethyl-4-nitrophenol (TFM) and niclosamide are used to control populations of invasive sea lamprey (Petromyzon marinus) in the Laurentian Great Lakes of North America. Added to streams infested with larval sea lamprey, the effectiveness of these pesticides, commonly called lampricides, are strongly influenced by water pH, with greater toxicity for both TFM and niclosamide in lower pH than higher pH water. However, the TFM and niclosamide sensitivity of sea lamprey are also greater in poorly buffered, low alkalinity water than in high alkalinity water but it is unclear why. One goal of my thesis was to propose …

Mechanistic Studies Of Co2 Electrochemical Reduction (Co2er) On Cu And Cuo Nanoparticles With In-Situ Atr-Ftir Spectroscopy, Jason Hsu

Theses and Dissertations (Comprehensive)

Global climate change is a major challenge facing the world in the 21st century. This environmental crisis originated from excess amounts of atmospheric carbon dioxide (CO2) released from burning fossil fuels. One promising remediation method to decrease atmospheric CO2 levels is called carbon dioxide electrochemical reduction (CO2ER). In CO2ER, the CO2 gas undergoes chemical reduction to other hydrocarbon fuels. For CO2ER to take place, an energy source and a catalyst are needed. In this thesis, three aspects of CO2ER were investigated using attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy coupled with other surface sensitive characterization tools. First, we studied …

Examining The Effects Of Noise And Task Dependent Performance In Prosody Perception In Autistic Individuals, Zehranur Sasal

Theses and Dissertations (Comprehensive)

ABSTRACT

Objective: It is known that autistic individuals have enhanced abilities in pitch discrimination and tend to excel in low-level tasks requiring lower cognitive processing. On the other hand, noise is a distracting factor in many areas of life, including prosody perception. The studies presented in this thesis aimed to understand prosody perception through different levels of cognitive tasks and under the influence of speech background noise.

Methods: In total, 256 non-autistic and 39 high-functioning autistic adults participated in these studies. In the first study, participants were asked to listen to brief utterances conveying one of six universally accepted emotions …

Differences In Drifting Invertebrate Communities Across Arctic Ecozones And The Influence On Potential Growth Of Grayling (Thymallus Arcticus), Charles Chanyi

Theses and Dissertations (Comprehensive)

Invertebrate drift is a key process that potentially affects multiple levels of food web organization within stream environments. However, our understanding of the mechanistic drivers of drift in high latitude streams and subsequent bottom-up control that drift may have on fish predators in these environments remains understudied. This project aimed to gain the baseline knowledge of how drift functions across two major high latitude ecozones, the boreal forest and tundra, and how those possible differences in drifting community characteristics may impact drift-feeding Arctic grayling (Thymallus arcticus). These objectives were accomplished by characterizing stream environments across both ecozones, sampling …

Best Practices For Social Workers Engaging With Spiritual/Religious Clients, Stewart J. Smith Mr.

Theses and Dissertations (Comprehensive)

This research examined what Canadian social workers should consider when engaging therapeutically with clients for whom spirituality/religion is of central importance. There are several challenges in examining this issue in Canada (the north section of Turtle Island). One is the oppression of Indigenous peoples’ spirituality by colonizers imposing various Christian denominational spiritual/religious views. There has also been a trend of Christian practice declining in church worship among settler people, although Christianity remains part of the dominant cultural norms. Like many of the helping professions, social work has little to no education/training related to spirituality/religion and clinical work. This move away …

Swimming Against The Tide: The Relational Praxis Of Social Justice In Social Work, Samantha Clarke

Theses and Dissertations (Comprehensive)

Swimming Against the Tide: The Relational Praxis of Social Justice in Social Work

Abstract

This qualitative research study explores the praxis of social justice by social workers who identify as practising social justice–oriented social work in southern Ontario, Canada. The research is set against the backdrop of the evolution of social justice in social work, its practice in the current neoliberal environment, and its continued significance in the profession. The project draws on critical and liberal social justice philosophies to ask the question: “What does social justice praxis look like in the context of contemporary social work?” This is a …

Phosphorus Release And Recovery From Simulated Ferric Wastewater Sludge, Aseel Alnimer

Theses and Dissertations (Comprehensive)

Phosphorus (P) is a fundamental element necessary for all life forms and a key component in the fertilizer industry. Meanwhile, the excessive load of P to water bodies due to human activities has the potential to promote eutrophication. Wastewater treatment plants remove P either biologically or chemically and produce P rich sludge which could be a potential renewable source for P. At present, commercial technologies exist for P recovery from biological wastewater sludge. However, P recovery from chemical sludge particularly iron(III)-phosphate (Fe-P) sludge generated in chemical P removal plants that use iron(III) salts remains a challenge.

This study explored, in …

Temperature Regulation Of Pipecolic Acid-Mediated Plant Systemic Immunity In Arabidopsis Thaliana, Alyssa Shields

Theses and Dissertations (Comprehensive)

Significant crop losses are caused by pathogenic infections annually, which are exacerbated by increasing global temperatures due to climate change. One way by which plants respond to pathogenic attacks is through the activation of pattern-triggered immunity (PTI), effector-triggered immunity (ETI), and systemic acquired resistance (SAR), which lead to production of the central defence phytohormone salicylic acid (SA). Accompanying SA release is the putative mobilization of pipecolic acid (Pip), which acts as an immune regulatory plant metabolite that works with and independently from SA. As demonstrated in the model plant Arabidopsis thaliana following infection with the model bacterial pathogen Pseudomonas syringae …

Contrasting Seasonal Cycling Of Arsenic In A Series Of Subarctic Shield Lakes With Different Morphometric Properties, Jeremy Harbinson

Theses and Dissertations (Comprehensive)

The subarctic shield near Yellowknife, Northwest Territories (NWT), is populated with thousands of small lakes (<1.5 km²) and several large lakes. Historic mining activities in the region have left a legacy of environmental impacts and widespread arsenic (As) contamination in both aquatic and terrestrial environments. In particular, several small subarctic lakes near Yellowknife have been previously documented to be contaminated with high levels of As. Subarctic lakes are characterized by seasonal ice-cover that can persist for more than half of the year, yet little is known about the under-ice spatial and seasonal dynamics of As cycling. The objective of …

Towards Ending Incarceration Of Indigenous Peoples In Canada: A Critical, Narrative Inquiry Of Hegemonic Power In The Gladue Report Process, Judah Oudshoorn

Theses and Dissertations (Comprehensive)

Abstract

This study is concerned with the possibility that Gladue perpetuates the hegemonic powers of settler colonialism, white supremacy, patriarchy, and neoliberalism. Gladue is intended to remediate systemic anti-Indigenous racism by requiring judges to consider all alternatives to incarceration when sentencing Indigenous peoples, yet Indigenous incarceration rates continue to rise precipitously. On the surface, Gladue does not appear to disrupt the hegemonic status quo. How is it that the Canadian state, even when ‘remediating,’ keeps producing the same – colonial, oppressive, and tyrannical – result?

This qualitative study used a critical, narrative methodology, interviewing Gladue report writers (n=9) and judges …

Intermittent Sucrose Access: Sweetness Versus Calories, Jarret Folmer, Rudy Eikelboom

Theses and Dissertations (Comprehensive)

Nondeprived rats receiving every 3^rd day access (E3DA) to 4% sucrose solution consume more sucrose on access days compared to rats with everyday access (EDA). Rats receiving EDA or E3DA to 16% sucrose do not consume different amounts, but if placed on every 2^nd day access (E2DA) to 4% sucrose E3DA-group rats consume more than EDA rats (Eikelboom, Hewitt, & Adams, 2022). E3DA affects rats’ value of sucrose but effects appear hidden with high sucrose concentrations. Valyear and Eikelboom (2021) suggested that calorie ceilings limit E3DA-induced consumption with high sucrose, but this ceiling could also be caused by …

The Design And Characterization Of Gold Nanoclusters As Elementary Building Blocks, Heather Gaebler

Theses and Dissertations (Comprehensive)

Gold nanoclusters with diameters in the quantum size regime (< ~2 nm) are promising building blocks for the design of novel nanomaterials as they exhibit unique size-dependent properties that can be altered and fine-tuned. The research outlined in this PhD thesis employs density functional theory to construct and analyze small ligand-protected cage and rod-shaped nanoclusters. Chapter 2 reports stable halide-protected gold nanocages that were engineered to have a closed-shell valence electron count of 18. This study finds that nanocages comprised of 19 and 20 gold atoms can be converted into stable magic number species containing 18 valence electrons by modifying their charged states via adsorption of halide ligands to the cage’s surface. Chapter 3 reports stable ligand-protected gold nanoclusters with a tetrahedral Au₄ core that were engineered to have a closed-shell valence electron count of 2. This study investigates the structural and electronic effects of halide and alkoxy ligands on the tetrahedral nanocluster and concludes that the results support the broader conclusion that it’s possible to fine-tune the stability and electronic properties of small gold nanoclusters using appropriate ligands. Chapter 4 reports stable gold nanorods that have diameters in the quantum regime that were constructed from elementary building blocks that contain “halide-staples”. This study presents different orientations of the “halide-staple” motifs on …

Still, We Thrive: Understanding How Gay, Bisexual, Transgender, And Other Men Who Have Sex With Men (Gbtmsm) Experience Structural Barriers & Facilitators To Wellness, Lucas Gergyek

Theses and Dissertations (Comprehensive)

Historically and concurrently, structural violence has been a significant force influencing the sexual health and broader health of gay, bisexual, transgender and other men who have sex with men (GBTMSM). Yet to date, the majority of projects exploring the health inequities facing GBTMSM have focused on intrapsychic and behavioural factors as most related to poor health outcomes. As well, these studies are sometimes deficits focused, and fail to evaluate how GBTMSM continue to thrive, and maintain positive health. As a result, the ways in which systems and policies underlie and perpetuate health inequities facing GBTMSM have been somewhat obscured. Connectedly, …

Potential Effects Of Road Proximity On Zooplankton Communities And Water Quality In Lakes In The Northwest Territories, Marie N. Hannan

Theses and Dissertations (Comprehensive)

Studies conducted along Canada’s Dempster Highway in the Northwest Territories have shown that road dust can affect water quality in roadside lakes, leading to higher calcium, conductivity, and pH levels. These water quality changes have the potential to affect important members of the lower aquatic food web, such as zooplankton.

For my thesis research, I had two main objectives: 1) To determine if changes in water chemistry caused by deposition of road dust affects zooplankton communities; and 2) To examine if the type of roadside vegetation influences the effects of road dust on aquatic habitats. To achieve these objectives, I …

Comparison Of Permafrost Thaw-Related Changes To Hydrological Response And Land Cover In Subarctic Peatland-Dominated Landscapes, Mikhail Mack

Theses and Dissertations (Comprehensive)

The hydrological implications of discontinuous permafrost thaw in peatland-dominated basins are not well understood. While there is evidence suggesting that permafrost-thaw-driven land cover change increases annual runoff and the runoff ratio in the Taiga Plains of northwestern Canada, few studies have evaluated the impact on small to medium-sized basins (< 10⁵ km²) outside this ecoregion. Here, we assess runoff, runoff ratio, and precipitation trends for 34 peatland-dominated basins, of which 28 are in the discontinuous and sporadic permafrost zones and 6 in adjacent permafrost-free environments. We calculated annual and monthly trends between 1970 and 2016 using the Mann-Kendall …

Dynamical Aspects In (4+1)-Body Problems, Ryan Gauthier

Theses and Dissertations (Comprehensive)

The n-body problem models a system of n-point masses that attract each other via some binary interaction. The (n + 1)-body problem assumes that one of the masses is located at the origin of the coordinate system. For example, an (n+1)-body problem is an ideal model for Saturn, seen as the central mass, and one of its outer rings. A relative equilibrium (RE) is a special solution of the (n+1)-body problem where the non-central bodies rotate rigidly about the centre of mass. In rotating coordinates, these solutions become equilibria.

In this thesis we study dynamical aspects of planar (4 + …

The Vital Role Of Dehcho Dene Knowledges In Climate Change & Permafrost Thaw Adaptation In Jean Marie River First Nation Nwt, Mackenzie Bell

Theses and Dissertations (Comprehensive)

Across the globe climate change has become an issue of growing concern for both Indigenous and non – Indigenous peoples alike. In Northern Canada this narrative is no different. For Indigenous groups such as the Jean Marie River First Nation (JMRFN) anthropogenic climate change is not only a reality but is visible through their daily interactions with the environment around them. Additional insight pertaining to these climatic changes and their impacts can be found through analyzing the traditional knowledge systems of the JMRFN and how these before mentioned interactions have changed over time. This two-year participatory research project has investigated …

The Long-Term Effects Of Cannabis On Attention To Motion, Rachel Mccaig

Theses and Dissertations (Comprehensive)

The purpose of the following study was to investigate the long-term effects of cannabis use on attention to motion.

Methods: Cannabis users, who varied in age of onset of use, were compared to control participants after abstaining from cannabis for at least 24 hours. One-hundred and ninety-seven participants engaged in a cognitive assessment followed by a motion discrimination task and an attention to motion task. The assessment consisted of a series of standard tasks that measured a range of cognitive processes such as attention, memory, and executive functioning. The motion discrimination task assessed the participants’ abilities in discriminating between various …

Exploring Graduated Court Diversion Clients' Experience Of Psychotherapy In Their Community Reintegration, Daniel Oduro Sem

Theses and Dissertations (Comprehensive)

Court Diversion Program (CDP) seeks to reduce the criminalization and reoffending among people living with mental illness to ensure their community reintegration (Schneider, 2010). The complex nature of achieving this goal calls for a comprehensive strategy, which requires a collaborative effort of legal, health care, and allied professionals including psychotherapists. However, because most CDP clients frequently receive medication treatment, not much is known about how CDP clients find psychotherapy services even though psychotherapy is effective for addressing mental illnesses and offending behaviors (Feingold & Fox, 2018; Feucht & Holt, 2016), To gain more insight into the issue, this study applied …

Exploring The Membrane Protein And Peptide Interactions Of Mitochondrial And Bacterial Lipid Systems, George Saudan

Theses and Dissertations (Comprehensive)

This study aims to expand the understanding of interactions between membrane lipids and proteins, and relate it to their biological functions in two experimental systems. The first system focuses on the interaction and conformation of a membrane protein Uncoupling Protein 4 (UCP4) in mitochondrial inner membrane lipids, in the absence and presence of cardiolipin; a lipid specific to mitochondrial inner membranes. The second system considers the interaction and conformation of a cell penetrating peptide, Penetratin, which can interact with both mammalian and bacterial cells. A N- and C-termini protected form of this 16-meric peptide (Pen2) was used to explore its …

Ethical Dilemmas And Moral Distress In Companion Animal Veterinary Medicine: Mental Health Implications, Bronwyn Dickson

Theses and Dissertations (Comprehensive)

Mental health concerns are a significant problem in the veterinary community, and studies suggest that veterinarians working in Western countries are at higher risk of suicide compared to the general population and other healthcare professionals (Bartram et al., 2009; Bartram & Baldwin, 2010; Platt et al., 2012). Additionally, veterinary medicine is an occupation inundated with complex ethical and moral dilemmas. However, current studies are limited in their ability to contextualize the risk and contributing factors fully; therefore, they offer limited insight into effective preventative and support strategies. Using Interpretive Phenomenological Analysis (IPA), eight companion animal veterinarians were interviewed about their …

Water Stories: An Exploration Of Human-Water Connectedness In Ontario And The Implications For Water Sustainability, Tracey Ehl

Theses and Dissertations (Comprehensive)

Abstract

Water is the great connector. Water connects people, health, wellness, culture, spirituality, nature, and the economy. Clean, safe water (potable water) and sanitation were recognized over a decade ago by the United Nations General Assembly (UN) as a basic human right, and more recently the UN has also identified water sustainability and management as one of 17 sustainable development goals for all people in all countries. Water is inextricably connected to humans. Yet, in Ontario, Canada, a place with access to some of the largest freshwater reserves in the world, robust regulatory frameworks, involvement, some investment by all levels …

Divest Or Disband?: A Social Problems Game Analysis Of Canadian Media Coverage Of 2020'S Defund The Police Movement, Nicholas Fappiano

Theses and Dissertations (Comprehensive)

Policing in Canada and America has come under the microscope due to several high-profile incidents of police violence against racialized citizens. The murder of George Floyd by officer Derek Chauvin thrust the concept of ‘defund the police’ to the mainstream public dialogue. To date, there are few studies that explore what defund the police means. The present media analysis addresses this research gap by analyzing how Canadian mass media covered the defund police movement. A social constructionist theoretical framework was utilized to analyze 109 newspaper articles on defund the police from The Toronto Star and The Globe and Mail. The …

The Effects Of Textured Foot Orthoses On Lower Leg And Plantar Foot Intrinsic Muscle Activity During Walking, Kelly Robb

Theses and Dissertations (Comprehensive)

The global foot orthotic industry was estimated around $3 billion in 2017. Biomechanists and clinical researchers have used foot orthoses (FOs) to study their effects on kinetic, kinematic, and muscle activity, although the mechanisms defining how a FO functions remain unclear. Recently, a neuromotor paradigm has been proposed suggesting that a FO augments the sensory feedback from foot sole skin and subsequently reduces muscle activity while optimizing movement. Although this paradigm currently lacks supporting evidence, neurophysiological research has linked foot sole skin to motorneuron pools of the lower extremity. Furthermore, one potential method of intentionally stimulating sensory feedback from the …