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Material-ecocritical relationality in Juli Zeh's Unterleuten
No full textThis thesis explores how the perspectives of human characters in Juli Zeh’s Unterleuten (2016) toward particular nonhuman entities can be understood as relationship-building agents rather than purely human-centered perceptions. While such perspectives are traditionally interpreted as human projections shaped by anthropomorphic cognition or cultural frameworks, this study argues that the role of nonhuman entities themselves in shaping and affording these perceptions warrants greater attention. Set in the fictional village of Unterleuten, the novel provides a rich ground for examining how human and nonhuman relationships are materially and affectively intertwined. Building up on the concepts of relationality, phenomenology, and sociomateriality, this thesis demonstrates that the characters’ motivations are not merely products of personal histories or individual experiences, but are deeply influenced by their entanglements with the village environment, for instance the wind, forests, animals, and especially the village land. Furthermore, it investigates how these relationships are disrupted and transformed with the arrival of a renewable energy corporation, highlighting the dynamic interplay between human and nonhuman agencies within a shared ecological and social space.Arts, Faculty ofCentral, Eastern, and Northern European Studies, Department ofGraduat
Perceptions and experiences of physical activity in pregnant women living in low-income Ger areas of Mongolia
No full textPhysical activity during pregnancy is influenced by many factors. Balanced against the accumulated evidence on the topic to date, prior research on factors that contribute to, or thwart, physical activity engagement during this important life stage has primarily been conducted in Western, high-income countries. The purpose of the study was to examine the experiences and perceptions of physical activity among pregnant Mongolian women living in low-income areas of Ulaanbaatar, Mongolia. Considering the unique sociocultural contexts and environmental challenges faced by Mongolian pregnant women (e.g., air pollution, extreme weather, and lack of infrastructure), I sought to examine factors at multiple levels (intrapersonal, sociocultural environment, physical environment, information environment, and policy environment) with respect to how they potentially contribute to the experiences and perceptions of physical activity in this population. Semi-structured interviews with 10 pregnant Mongolian women living in low-income areas of Ulaanbaatar were conducted in Mongolian, and were designed to ensure cultural sensitivity. The transcripts were coded in Mongolian, translated into English, and subsequently analyzed using reflexive thematic analysis. Four themes (and 17 subthemes) were developed through reflexive thematic analysis. These included: (1) Pregnant Mongolian women’s perceptions of physical activity, (2) A battle against the barriers: The realities of pregnant Mongolian women in the Ger areas, (3) Worry as a double-edged sword: A barrier and a driver of physical activity during pregnancy, and (4) Fueled by resilience and desire: Navigating barriers and seeking opportunities for better health and physical activity. When taken together, participants described facing a range of barriers with regard to living in Ger areas as a pregnant woman. These barriers often limited their ability to be as active as they would like. While determination and resilience were key to staying active, participants noted that with certain improvements, pregnant women could achieve better health and greater participation in physical activity. The significance of this research lies in its potential to expand our understanding of physical activity during pregnancy within a unique sociocultural and environmental context, shedding light on the experiences of pregnant women with notable economic and environmental challenges.Education, Faculty ofKinesiology, School ofGraduat
Assessing and reducing fear in cattle using training
No full textDairy cattle experience a variety of stressors associated with routine farm practices. These events can cause fear responses that make the procedure challenging for the animal and the human handler. Positive reinforcement training (PRT) is used to reduce fear responses and there is evidence that this can facilitate handling on dairy farms. The aim of this thesis was to explore emotional responses, particularly fear, during handling events and to test if PRT had any effect on those responses.
In the first chapter I reviewed literature on methods to assess emotion in animals, with a particular focus on fear and training literature. In the second chapter, I tested the effect of PRT on anticipatory and play behaviour in dairy heifers entering a restraining chute. I found that PRT results in heifers having more positive emotional states in anticipation of handling; these results support the use of training to improve welfare. In the third chapter, I assessed ear position and body movement responses of heifers during their first experience of artificial insemination and compared responses during baseline observations before and after this procedure and whether heifers exposed to PRT responded differently to this procedure. I found that heifers experiencing artificial insemination showed distinct ear positions consistent with responses to a negative emotional state but noted no differences between trained and untrained heifers. In the fourth chapter, I assessed behavioural responses associated with fear when cows were first introduced to an automatic milking system (AMS) and evaluated if these responses were affected by training. I found that an enhanced training protocol did not provide additional benefits beyond baseline training for the outcome measures examined.
The results of my thesis illustrate that the training methods used in the studies described showed both benefits and limitations in mitigating fear-inducing procedures in dairy cattle. I suggest that future training efforts introduce each potentially fear-inducing stimulus separately, so as to improve the ability to mitigate fear responses. My work illustrates the promise of using anticipatory behaviours and ear positions to assess emotional states in cattle, suggesting that these measures may also be useful for future research.Land and Food Systems, Faculty ofGraduat
Development of sustainable and industrially viable wood-based advanced materials : enhancing functional and structural properties
No full textApproximately 30% of worldwide greenhouse gas emissions originate from industrial activities, with major contributions coming from the production of steel, concrete, and chemicals (such as plastics). The challenge in decarbonizing these sectors lies in the need for biodegradable and renewable materials obtained from natural biomass which are excellent candidates to replace materials obtained from petrochemicals or through energy-intensive processes (for instance, metal/alloys or concrete). Wood is an environmentally sustainable, benign, and high-performing green structural material readily available in nature which can be used to replace structural materials. However, insufficient mechanical performance, moisture sensitivity, and vulnerability to fire and microorganism attack make it challenging to use the wood as it is in advanced engineering applications. Chemical modification, physical modification and carbonization are some of the ways to enhance the functionality, strength and physical property of the wood. Alkaline pretreatment (delignification) followed by physical densification can transform the low-density wood into a densified wood composite with exceptional strength. Despite efforts for many years, mass commercialization of either bulk or surface-densified wood products have not yet been achieved. Because traditional densification methods are time-consuming, energy-intensive, and requires post-treatment to meet end requirements. This thesis is focused on understanding the use of benign chemical as polylactic acid, colloidal silica and use of deep eutectic solvent to chemically modify the wood during densification process. This proposed project will test the hypothesis that physical densification combined with chemical modification will reduce the densification time and energy and impart not just high mechanical performance but also the functionality (water repellency, flame retardant, surface hardness) based on the chemical modifier used. Moreover, to take one step further, we also showcased the ability of utilizing wood for non-structural applications for electromagnetic interference shielding by combining iron salt with the carbonization technique. In conclusion, the research proposed in this thesis has tried to address the research gaps in the densification domain to make it an industrially viable process and to highlight wood’s ability not just for structural but also for advanced application for electromagnetic shielding.Applied Science, Faculty ofChemical and Biological Engineering, Department ofGraduat
Phenomic characterization of C. elegans orthologs of Parkinson's disease-associated genes
No full textThe full abstract for this thesis is available in the body of the thesis, and will be available when the embargo expires.Medicine, Faculty ofGraduat
Liquidity, liability, and bank risk-taking
No full textIn this thesis, I investigate how limited liability and aggregate uncertainty influence banks’ chosen portfolio liquidity. I use a three-period theoretical model inspired by Diamond and Dybvig (1983) and Allen and Gale (2004). The model features correlated withdrawals and interest rate shocks which cause asset values to fall and depositors to withdraw simultaneously. These features are inspired by the conditions that lead to the failures of Silicon Valley Bank and Silvergate Bank, which were characterized by unusually high interest rate and concentration risk related to cryptocurrency and venture-capital investments. Using this model, I examine outcomes under limited and unlimited liability and evaluate whether liquidity regulations similar to those introduced under Basel III can mitigate the likelihood and severity of runs and improve welfare. I find that limited liability generates a moral hazard by encouraging banks to under-insure against and tolerate a higher probability of runs. Liquidity requirements can prevent runs ex-post, but they do not improve welfare ex-ante as they fail to address the incentives and moral hazard created by the liability structure. When liability is unlimited, banks internalize the cost of runs and choose more liquid portfolios.Arts, Faculty ofVancouver School of EconomicsGraduat
The river between Sohni and Mahiwal : fluid ecologies of genre, land, and gender in a Punjabi narrative tradition
No full textThe full abstract for this thesis is available in the body of the thesis, and will be available when the embargo expires.Arts, Faculty ofAsian Studies, Department ofGraduat
On gapless topological phases and their holographic duals
No full textDespite great success we have achieved in the past two decades on systematically understanding gapped topological phases, a firm foundation for understanding gapless topological phases is still lacking. In this dissertation I develop a general framework to describe, classify and construct gapped and gapless phases with or without symmetry. I then apply this framework to construct new gapless phases, and classify some classes of them completely.
The first chapter is a non-technical summary of the subjects, ideas and results of the rest of the dissertation. In the first chapter I introduce the notion of gapless topological phases, and briefly discuss their general structures. We also discuss how topological holography can be useful for classifying and constructing gapless phases with generalized symmetries.
In chapter two I develop a framework for understanding general quantum phases and phase transitions with generalized symmetries. After reviewing the established theory of gapped phases, we introduce two key notions: quantum order and symmetry-enriched quantum order. These concepts are the correct generalized of topological order and symmetry-enriched topological orders. I show that these new notions subsume conventional phase transitions, gapless spin liquids, and gapless symmetry-protected topological phases. For a class of symmetry-enriched quantum orders with finite many topological defects, we present a general classification using higher tensor category theory.
The rest of the dissertation provides more detailed studies of specific gapless topological phases, including classification and lattice model construction of gapless symmetry-protected topological phases and the connection to the theory of topological holography.Science, Faculty ofPhysics and Astronomy, Department ofGraduat
Engineering fluorescence-based synthetic biology tools to interrogate gut ecosystem biogeography
No full textThe full abstract for this thesis is available in the body of the thesis, and will be available when the embargo expires.Science, Faculty ofMicrobiology and Immunology, Department ofGraduat
The microbiome and innate lymphoid cells as sculptors of chronic inflammatory disease
No full textA tightly regulated immune response is essential to ensure protection from the plethora of microbial pathogens we encounter, while simultaneously averting spurious responses to innocuous environmental antigens, self-antigens, or commensal microflora. Advances in Western medicine and sanitation have dramatically reduced mortality and morbidity linked to infectious diseases, but at a cost: diminished microbial exposure has inadvertently altered normal immune cell development and heightened the risk of autoinflammatory and autoimmune disorders. Innate lymphoid cells (ILCs) are recently discovered innate counterparts of T lymphocytes but lack antigen specific T cell receptors. These cells colonize peripheral tissues in waves during pre and early postnatal development and subsequently become critical, long lived tissue resident regulators of immunity. Given their early developmental tissue colonization, longevity, and role as first responders in inflammation, ILCs are ideally positioned as regulators of long-term immune sculpting by the gut microbiome.
I generated a novel transgenic mouse strain (Il17rb-CreERT2-eGFP) to selectively target ILC2s. Loss of gastrointestinal ILC2s led to increased ILC3/Th17 responses, and heightened susceptibility to Crohn’s disease–like fibrosis. Conversely, dampening ILC3/Th17 responses using isolithocholic acid (isoLCA), a microbial secondary bile acid and RORγt inverse agonist, reduced interleukin-17 (IL-17) production, protecting against fibrosis.
Employing mouse models of allergic airway inflammation, I demonstrate that perinatal exposure to low doses of vancomycin amplified allergic responses in adulthood. ILC2s emerged as key regulators of peripheral type 2 immune sculpting, driving innate natural immunoglobulin E (IgE) production by B1 B cells and increased surface bound IgE on basophils and mast cells, exacerbating allergic inflammation. This enhanced lung ILC2/B1 cell/effector cell axis was completely suppressed with dietary short-chain fatty acid SCFA supplementation. Conversely, streptomycin treatment heightened susceptibility to hypersensitivity pneumonitis, marked by increased lung ILC3s and Th17 cells, and was significantly ameliorated by isoLCA or selective mammalian target of rapamycin complex 1 (mTORC1) inhibition. This highlights that antibiotic-induced dysbiosis, by skewing microbial communities, is remarkably selective in its effects on immune sculpting, with vancomycin exacerbating Th2-disease and streptomycin exacerbating Th1/Th17-linked diseases.Applied Science, Faculty ofBiomedical Engineering, School ofGraduat