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Nitrogen Transfer From Cover Crops To The Subsequent Grain Crop And The Influence Of Variability In Winter Conditions, Spencer Heuchan

Electronic Thesis and Dissertation Repository

Cover crops, which are used to provide ground cover after the harvest of the grain crop, can potentially improve the sustainability of agroecosystems by reducing nutrient losses. However, few data are available to document the extent to which cover crops improve both the retention of soil nitrogen (N) and the transfer of this N to the grain crop. The efficiency of this N transfer may be further influenced by variation in winter soil temperature; for example, reduced snow cover can increase the frequency and intensity of soil freezing, which can affect the survival of cover crops and the timing of …

Secretion Of Salivary Proteins And Their Interactions, Karla Tonelli Bicalho Crosara

Electronic Thesis and Dissertation Repository

Saliva’s clinical application for disease diagnosis and monitoring is limited by incomplete knowledge of salivary protein interactions, the effect of stimulation on the salivary proteome, and if these factors impact protein identification. This thesis expands knowledge of the salivary interactome and effects of stimulation intensity and duration on parotid saliva’s proteome. First, previous in vitro studies identified 43 proteins in the histatin 1-protein network and demonstrated histatin 1’s increased stability in whole saliva when interacting with amylase. We hypothesized that protein-protein-interaction databases could enlarge the histatin 1-protein network. A comprehensive histatin 1-protein network was created using STRING database, merging previous …

Enhanced Performance Of 3d Electroactive Polymer Transducers Via Hierarchical Structures, Frederick B. Holness

Electronic Thesis and Dissertation Repository

Conjugated polymers (CPs) are a class of polymers that exhibit a change in size or shape in response to electrical stimuli. The unique combination of electrical and mechanical properties facilitates the fabrication of novel devices in a broad range of applications including: sensors, actuators, and lab-on-a-chip systems. The alternating single and double bonds along the polymer chain of CPs enables their electroactive properties but is also responsible for processability associated with CPs that has limited fabrication methods. Recently a photosensitive CP composite enabling additive manufacturing (AM) of 3D CP structures was developed. However, the introduction of a copolymer for mechanical …

Essays On Privilege And Its Implications For Relational Autonomy And Vaccine Hesitancy, Nicole Fice

Electronic Thesis and Dissertation Repository

One goal of feminist philosophy is to challenge unjust systems of power like patriarchy, which privilege some social groups while oppressing others. In this three-chapter dissertation, I argue that to achieve this goal, we need a better understanding of privilege and its implications.

In chapter one, I raise objections to some existing philosophical accounts of privilege. These accounts are either too broad in defining privilege as always advantageous or they are vague regarding what privilege comprises. I provide an account of privilege which clarifies that privilege is generally advantageous and that privilege includes tangible resources and options to do certain …

Social Determinants Of Access To Primary Care In Canada, Feben W. Alemu

Electronic Thesis and Dissertation Repository

Despite the promise of universal care, many Canadians report having unmet healthcare needs. We conducted two studies: (1) a systematic review of studies on social determinants of health (SDH) and unmet need; and (2) a secondary analysis using the Canadian Longitudinal Study on Aging (CLSA) to investigate the association of SDH and (2a) self-reported unmet need and (2b) having a family physician. The review (n=40) found a positive association between unmet need and lower income, mental health and chronic conditions, and negative association with older age, better perceived health and having a family physician. The CLSA analysis found the odds …

The Effect Of Postural Perturbations On Cardiovascular And Skeletal Muscle Function In Healthy Adults, Patrick Siedlecki

Electronic Thesis and Dissertation Repository

Maintenance of standing balance is vital to daily living. Traditionally, perspectives on maintaining balance are achieved through the study of visual, vestibular and somatosensory inputs on motor outputs. While evidence suggests cardiovascular regulation also functions to assist postural control during orthostatic stress, how the cardiovascular system responds to postural perturbations is not well established. This dissertation includes four studies that investigated the effects of postural perturbations on the cardiovascular system and skeletal muscle responses in healthy adults. All of the studies involved exposing standing participants to surface-translation perturbations at different velocities, with known or unknown timing, and occurred while spontaneously …

Discourse, Power Dynamics, And Risk Amplification In Disaster Risk Management In Canada, Martins Oluwole Olu-Omotayo

Electronic Thesis and Dissertation Repository

The domain of disaster risk management is rife with discursive contentions, whereby dominant discourses amplify the powers of risk actors to precipitate and reinforce political, economic, and environmental inequalities that predispose different sections of the population to unequal disaster risk vulnerabilities. This thesis identified important actors (government, risk experts, media, and NGOs) that shape the power dynamics in disaster risk management in Canada and explained their roles, influences, and the dimensions in which their powers negotiate each other through risk discourses. The patterns of these power dynamics in the three aspects of power –communication, assessment, and social trust –were also …

Noninvasive Quantification Of Tissue Sodium Concentration In The Kidney Disease Spectrum Using 23na Magnetic Resonance Imaging, Fabio R. Salerno

Electronic Thesis and Dissertation Repository

Chronic kidney disease (CKD), especially when requiring kidney replacement therapy (hemodialysis (HD) and peritoneal dialysis (PD)), is associated with extracellular water expansion with increased total body sodium. Sodium can also be accumulated in tissues independently of extracellular water. Sodium-23 magnetic resonance imaging (²³Na MRI) can quantify the concentration of sodium nuclei in tissues. Applied to the human leg, quantification of tissue sodium concentrations mainly at the skin and muscle level is possible. We hypothesized that increased tissue sodium concentrations exert toxic effects in CKD and dialysis. We aimed to (1) compare tissue sodium concentrations in adults, children and …

Effects Of Climate Change On The Probability Of Urban Tree Failures From Wind Gusts, Samuel J. Woolsey

Electronic Thesis and Dissertation Repository

Trees grown in urban environments provide environmental, economic and psychological benefits to their surrounding communities. However, urban trees also pose significant risks since damaged trees can cause serious harm to people, housing, and infrastructure by falling on sidewalks, roads, houses or power lines. To better understand the risk posed to trees by wind, models have been developed that estimates the required wind speed needed to damage a tree or group of trees, and the likelihood that such a wind speed is met or exceeded annually. The importance of such models is rising each year as the associated risk grows as …

Synthesis And Surface Modification Of Azide Decorated Silver Nanoclusters, Alexander H. Stöckli

Electronic Thesis and Dissertation Repository

In nanocluster research, easy modification of the cluster surface while maintaining the cluster core remains a key challenge. Herein we report the synthesis, structure, and properties of four targeted Ag₂₀ nanoclusters (NCs) with surface azide moieties, two of which have 8 azide moieties, [CO₃@Ag₂₀(S^tBu)₁₀(m-N₃-C₆H₄COO)₈(DMF)₄] and [CO₃@Ag₂₀(S^tBu)₁₀(p-N₃-C₆H₄COO)₈(DMF)₄], and two of which have 6 azide moieties, [CO₃@Ag₂₀(S …

Gene Regulatory Context Of Honey Bee Worker Sterility, Rahul Choorakkat Unnikrishnan

Electronic Thesis and Dissertation Repository

Honey bee workers deactivate their ovaries and are functionally sterile when a queen is present in the colony. I adopt a bioinformatics approach to up-date a model transcriptional regulatory network (TRN) to study gene-regulatory processes that regulate fecundity in workers. On splitting the network, I obtained nine clusters and each cluster conformed to properties associated with real-world networks. Two of the nine clusters are enriched for 'sterility genes' and contained single well-connected hub genes (GB44769, ftz-f1). The genes in the two clusters were functionally enriched for nucleic acid binding (GO:0003676) and nucleotide binding (GO:0000166). I identified homologous genes for …

On The Spatial Modelling Of Biological Invasions, Tedi Ramaj

Electronic Thesis and Dissertation Repository

We investigate problems of biological spatial invasion through the use of spatial modelling. We begin by examining the spread of an invasive weed plant species through a forest by developing a system of partial differential equations (PDEs) involving an invasive weed and a competing native plant species. We find that extinction of the native plant species may be achieved by increasing the carrying capacity of the forest as well as the competition coefficient between the species. We also find that the boundary conditions exert long-term control on the biomass of the invasive weed and hence should be considered when implementing …

Effects Of Methylmercury And Unpredictable Food Stress Exposure On Songbirds’ Physiology And Seasonal Transition, Claire L.J. Bottini

Electronic Thesis and Dissertation Repository

Organisms regularly adjust their physiology to respond to predictable seasonal or environmental variation. However, annual cycle transitions could be disrupted by contaminants or stressors. For example, methylmercury and stress exposure can independently disrupt birds’ neural and endocrine systems, energy balance, metabolism, or behaviour, all necessary for seasonal transitions. Although, the effects of combined exposure to stressors and methylmercury (MeHg), and how long they last after exposure ends, are poorly understood. The objective of my PhD was to evaluate the impact of MeHg exposure on songbirds’ physiology and its potential carry-over effects on seasonal transitions. I exposed song sparrows (Melospiza …

Data-Driven Neuroanatomical Subtypes In Various Stages Of Schizophrenia: Linking Cortical Thickness, Glutamate, And Language Functioning, Liangbing Liang

Electronic Thesis and Dissertation Repository

The considerable variation in the spatial distribution of cortical thickness changes has been used to parse heterogeneity in schizophrenia. We aimed to recover a ‘cortical impoverishment’ subgroup with widespread cortical thinning. We applied hierarchical cluster analysis to cortical thickness data of three datasets in different stages of psychosis and studied the cognitive, functional, neurochemical, language and symptom profiles of the observed subgroups. Our consensus-based clustering procedure consistently produced a subgroup characterized by significantly lower cortical thickness. This ‘cortical impoverishment’ subgroup was associated with a higher symptom burden in a clinically stable sample and higher glutamate levels with language impairments in …

“Literally, A Game-Changer”: Renegotiating The Aesthetics Of The Real, Moira Mckee

Electronic Thesis and Dissertation Repository

The affirmation of identity as a leitmotif throughout art history has become increasingly concerned with the conflation of the real and constructed, the material and immaterial, as technological developments engineer the fabric of reality with heightened sophistication. In the age of lifelike, digital avatar influencers such as Lil Miquela, Ai-Da, billed as “the world’s first ultra-realistic robot artist,” algorithms developed to create The Next Rembrandt, and the rise of crypto art and non-fungible tokens (NFT’s), the ambiguity or removal of the hand of the artist prompts questions surrounding identity as a visualization of the data that follows us and is …

Malencontres Coloniaux Et Bâtardises Postcoloniales. Pour Une Poétique Du Fait Colonial Et De L'Hybridité Chez Tierno Monénembo, Antoine Marie Zacharie Habumukiza

Electronic Thesis and Dissertation Repository

Cette thèse analyse la représentation du fait colonial dans l’ensemble de l’œuvre littéraire de Tierno Monénembo. Son périple scriptural à travers les plis tant du passé colonial que du néo-colonialisme contemporain, ne cesse d’exhumer du tréfonds du bassin historique des ingrédients méticuleux et combien diversifiés mais ayant à la fois comme origine et comme fin le brassage culturel et humain, marqué à tout jamais du sceau indélébile du postcolonial.

S’appuyant, d’une part, sur des théories postcoloniales et, d’autre part, sur des théories multidisciplinaires portant sur le nom, la nomination et l’onomastique littéraire d’abord, et sur les notions de parenté et …

Quantification Of Flows Emerging From Small Pores In Plane Walls, Matia Peter Edwards

Electronic Thesis and Dissertation Repository

Current membrane separation processes are limited in high production and high purity settings due to a trade-off between selectivity and permeance. Methods of creating nanoscale geometries in 2D materials are emerging and present an opportunity for fast, size selective mass transport that can be tailored to a wide array of applications. This thesis develops a method for quantifying flow through small pores in plane walls based on the behaviour of a solute dispersed in a downstream reservoir. This method is validated for a range of micropore diameters, for which flow rates can be calculated with confidence, and is shown to …

Comparison Of Hip Navigation System Accuracy In Direct Anterior Approach, Jeremy Loh

Electronic Thesis and Dissertation Repository

Introduction

Malposition of the acetabular component has been thought to have an influence on increasing increase the risk instability, impingement, and ultimately revision surgery. Hip navigation technology has been developed to provide the surgeon with real time intraoperative metrics to make critical decisions in implant placement. The goal of this study was to compare the accuracy of acetabular component positioning in direct anterior approach hip replacements using conventional fluoroscopy only technique, fluoroscopic image dependent navigation, and imageless navigation.

Methods

A retrospective data collection and prospective analysis was conducted for this study. After sample size calculations, fifty patients were collected for …

Postexercise Executive Function Benefits And Cerebral Blood Flow: In The Lab And At Home, Benjamin Tari

Electronic Thesis and Dissertation Repository

A single bout of aerobic exercise improves executive function; however, the mechanism, or mechanisms, supporting this improvement remain unclear. One candidate mechanism is an exercise-mediated increase in cerebral blood flow (CBF) that enhances the efficiency of executive-related frontoparietal networks. To evaluate the link between exercise, CBF and executive function, three separate experiments were conducted. In the first study, separate 10-min sessions of moderate-to-heavy-intensity aerobic exercise, and a hypercapnic environment (i.e., 5% CO₂) were implemented. The hypercapnic condition was included because it increases CBF independent of the metabolic demands of exercise. The second study investigated whether exercise intensity-specific changes …

The Effect Of Oral And Topical Antibiotics On Foreskin Inflammation And Hiv Target Cells In Ugandan Men., Zhongtian (Eric) Shao

Electronic Thesis and Dissertation Repository

Penile circumcision reduces HIV susceptibility by up to 60% in men; however, many men prefer to remain uncircumcised for personal or cultural reasons. Penile circumcision protects against HIV by reducing anaerobic bacteria on the penis. Penile anaerobes cause local inflammation and the recruitment of HIV-susceptible CD4+CCR5+ cells, increasing the likelihood that exposure to HIV during intercourse results in infection. To determine if a non-surgical intervention can reduce penile anaerobes and HIV target cells, we randomized men to antimicrobial treatment prior to circumcision. To be able to quantify the effect of antimicrobials, we developed a novel deep-learning algorithm to quantify HIV …

Canadian Olympic Athletes, Gender Issues And Body Dissatisfaction: A Critical Analysis Of The Impact Of Covid-19 And Canadian Sport Resources, Alyssa Mcculloch

Electronic Thesis and Dissertation Repository

This multidisciplinary study has three main aspects and is guided by a critical feminist lens. One aspect lays out the philosophical feminist foundations, the context for the study and provides a literature review and brief history. A second aspect is guided by research questions which explore how COVID-19 impacted Canadian female Olympic athletes. Qualitative interview data was collected during a Social Sciences and Humanities Research Council (SSHRC) funded study and used for the empirical part of this paper. Participants included ten national level athletes (seven females and three males) and three coaches (two females and one male) from a variety …

Reclaiming Ancestral Territory In Biigtigong Nishnaabeg: Applying Strategies Of Environmental Repossession For Indigenous Decolonization, Elana Nightingale

Electronic Thesis and Dissertation Repository

Relationships to land are foundational for nurturing knowledge systems, identities, and wellness among Indigenous peoples. As Indigenous peoples resist enduring structures of colonialism and rebuild self-determination, they are pursuing diverse strategies to reclaim and reconnect with their lands and land-based practices. While this movement is growing globally, few empirical studies have explored why particular strategies are developed nor how they are operationalized in place. In partnership with Biigtigong Nishnaabeg, this dissertation applies the concept of environmental repossession to document the spatial strategies being implemented to reoccupy, reconnect with, and reassert Biigtigong’s rights to its ancestral territory. Drawing from Indigenous and …

Driver Behavior Analysis Based On Real On-Road Driving Data In The Design Of Advanced Driving Assistance Systems, Nima Khairdoost

Electronic Thesis and Dissertation Repository

The number of vehicles on the roads increases every day. According to the National Highway Traffic Safety Administration (NHTSA), the overwhelming majority of serious crashes (over 94 percent) are caused by human error. The broad aim of this research is to develop a driver behavior model using real on-road data in the design of Advanced Driving Assistance Systems (ADASs). For several decades, these systems have been a focus of many researchers and vehicle manufacturers in order to increase vehicle and road safety and assist drivers in different driving situations. Some studies have concentrated on drivers as the main actor in …

Developing Carbon Quantum Dots As A Luminescent Material And Revisiting Ecl And Led Absolute Measurement Methods, Jonathan Ralph Adsetts

Electronic Thesis and Dissertation Repository

Luminescent materials play increasingly important roles in our lives. Improvements in these materials’ quantum efficiencies (QEs), costs and toxicity can greatly reduce the power consumption, price and environmental damage to the planet, respectively. Carbon quantum dots (CQDs) and luminescent materials exhibiting thermally activated delayed fluorescence (TADF) are two interesting materials in these aspects. Furthermore, measurements on electrochemiluminescence (ECL) and electroluminescence of these luminescent materials can quickly evaluate their performance for many applications. In this thesis, controlled CQD syntheses are revealed beneficial to luminescent materials applications. Their film ECL demonstrated relatively stable anionic and cationic radicals leading to high emission at …

Mindfulness With Children And Youth: A Hermeneutic Phenomenological Inquiry Into Paediatric Therapists' Experiences, Kirsten S. Smith

Electronic Thesis and Dissertation Repository

Background: Mindfulness has become popular as a treatment approach for many health conditions and has been taken up by diverse health practitioners in recent years. While research into mindfulness-based interventions is on the rise, much of this research originates in the field of psychology and is aimed toward adult populations. Occupational therapists, including those working with children and youth, have begun to take up mindfulness to support their clients to participate in daily activities, and there is evidence that clinical uptake has outpaced research in this area.

Method: A scoping review was undertaken to understand the breadth of literature regarding …

A Visual Analysis Of The Smart Home, Seyedeh Sara Sadati Far

Electronic Thesis and Dissertation Repository

To date, studies related to the smart home have often focused on the technical aspects of the home. Few have given attention to how ‘smartness’ is reconfiguring a sense of home and how these changes may be identified in the smart home’s visual signatures. This research closes this gap in the current literature by mobilizing a visual methodologies approach comprised of content, compositional, and semiotic analysis to identify whether and how visual representations of the ‘smart home’ in architectural trade publications reconfigure understandings of the meaning of the "home.”

The outcomes of this research are a typology of smart home …

The Social Context Of Nonverbal Behaviour, Alexa S. Clerke

Electronic Thesis and Dissertation Repository

Although nonverbal behaviour has long been a topic of research, it is often studied in isolation from social partners and the social environment. This work presents three empirical chapters that reintroduce the social environment to the investigation of nonverbal cue exchange, focusing on the value of social rewards and the perceptive and affiliative functions of nonverbal communication. Findings reported in Chapter 2 indicate that the subjective value of social rewards changes as a function of social media use saliency. Specifically, thinking about a recent social media post, but not a synchronous conversation, increases the value of social rewards, such that …

Total Hip Arthroplasty In Young Patients, Aaron G. Chen

Electronic Thesis and Dissertation Repository

Total hip arthroplasty (THA) is the gold standard in treatment of hip arthritis yet is often avoided in young patients due to concerns of inferior survivorship. We aim to explore the role of THA in young patients and assess whether these historical concerns are valid in contemporary THA by presenting the results of: (1) a systematic review and meta-analysis of the current literature, (2) a retrospective database review, and (3) a retrospective population-based study. We found excellent long-term survivorship with modern THA in young patients, demonstrating greater than 90% revision-free survival up to 15 years. Factors that may increase risk …

Portfolio Optimization Analysis In The Family Of 4/2 Stochastic Volatility Models, Yuyang Cheng

Electronic Thesis and Dissertation Repository

Over the last two decades, trading of financial derivatives has increased significantly along with richer and more complex behaviour/traits on the underlying assets. The need for more advanced models to capture traits and behaviour of risky assets is crucial. In this spirit, the state-of-the-art 4/2 stochastic volatility model was recently proposed by Grasselli in 2017 and has gained great attention ever since. The 4/2 model is a superposition of a Heston (1/2) component and a 3/2 component, which is shown to be able to eliminate the limitations of these two individual models, bringing the best out of each other. Based …

The Developmental Importance Of Napping In Preschool Children, Adam T. Newton

Electronic Thesis and Dissertation Repository

Most children cease napping between 2- and 5-years-old. Little is known about the predictors or outcomes related to this cessation, or the interrelation of different components of nap behavior. Four empirical studies were conducted to investigate the developmental importance of napping among preschool children.

Studies 1 and 2 used a large, longitudinal sample of Canadian children to investigate the predictors (Study 1) and outcomes (Study 2) related to early nap cessation. Early nap cessation was defined as stopping daytime sleep before three years old. In Study 1, parents reported on their own, child, and family functioning at two timepoints (0-1 …