Graduate Theses & Dissertations

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Expression optimization and NMR spectroscopy of Giardia intestinalis cytochrome b5 isotype III
The parasitic protist Giardia intestinalis does not synthesize heme and lacks many common eukaryotic heme proteins, yet it expresses four cytochrome b5 (gCYTB5) isotypes of unknown function. These have low reduction potentials and distinct subcellular locations that are consistent with structural features and biological functions that differ from their mammalian counterparts. Isotype III (gCYTB5-III) is particularly fascinating for its unusual location in the nuclei of Giardia. This thesis reports the optimization of recombinant gCYTB5-III overexpression for structural studies by NMR spectroscopy. Vital optimization factors for isotope labelling were first identified, finding that auto-induction promotes the optimization of many other conditions, such as colony selection, starter cultures, media components, temperature, pH and aeration. Optimized conditions were then applied to the expression and NMR spectroscopy of isotope-labelled gCYTB5-III and bovine cytochrome b5 as a control. These results can be extended to other heme proteins and will expand our biochemical knowledge of Giardia. Author Keywords: Auto-induction, Cytochrome b5, Giardia intestinalis, Isotope Labelling, Nuclear Magnetic Resonance Spectroscopy, Recombinant Protein
“It's like getting a new car without the manual”
This study explored teacher infusion of Indigenous curriculum content through interviews with ten non-Indigenous teachers of social studies and history. The interviews centered on teacher perceptions of preparedness to implement Ontario’s recent TRC curriculum revisions, which include more about the contributions, histories, cultures, and perspectives of Indigenous peoples. A brief analysis of Ontario’s First Nation, Métis, and Inuit Education Policy Framework is included, alongside critiques of the Eurocentrism at the heart of education systems. The interviews revealed that many of the teachers were committed to Indigenous education and learning more, but they felt unprepared and lacked resources to teach Indigenous curriculum content with confidence. This study highlighted the critical role of settler teachers in Indigenous education and the importance of teachers undertaking settler unsettling in order to be effective and appropriate in Indigenous curriculum delivery. Individual changes must occur alongside educational system decolonization with a particular focus on teacher preparation. Author Keywords: cognitive imperialism, Indigenous Education, Ontario, settler educator, settler unsettling, TRC curriculum
Detectability and its role in understanding upland sandpiper (Bartramia longicauda) occurence in the fragmented landscape of southern Ontario
Upland Sandpipers (Bartramia longicauda), like many grassland birds, are undergoing population decline in parts of their range. Habitat fragmentation and change have been hypothesized as potential causes of decline. I used citizen-science occurrence data from Wildlife Preservation Canada’s Adopt-A-Shrike Loggerhead Shrike (Lanius ludovicianus) program in conjunction with validation surveys, using similar point-count methods, to examine detectability and determine if landscape level habitat features could predict occupancy of Upland Sandpipers in Southern Ontario. In a single season detectability study, I used Wildlife Preservation Canada’s survey protocol to determine detectability in sites that were known to be occupied. Detectability was low, with six surveys necessary to ensure detection using a duration of at least 18 minutes early in the breeding season. The proportion of open habitat did not affect detection on the landscape. Using a larger spatial and temporal scale, with five years of citizen-science data, I showed that Annual Crop Inventory data could not effectively predict Upland Sandpiper occupancy. Model uncertainty could be attributed to survey protocol and life history traits of the Upland Sandpiper, suggesting that appropriate survey methods be derived a priori for maximizing the potential of citizen-science data for robust analyses. Author Keywords: Bartramia longicauda, citizen-science, detection, landscape, occupancy, Ontario
Modelling the Lanthanum Aluminate-Strontium Titanate Interface with a Modified Transverse Ising Model
In 2004 it was discovered that a two-dimensional electron gas (2DEG) forms at the interface between lanthanum aluminate (LAO) and strontium titanate (STO). This 2DEG exhibits a variety of electronic and magnetic phenomena, motivating intense research into its applicability to electronic devices. Over the years several models have been developed in theoretical exploration of this system. Here, the transverse Ising model is applied to the LAO/STO interface for the first time. It is shown that the model as it is traditionally formulated cannot accurately predict the structure of the electron density at the interface. I show that this can be fixed with a simple modification of the model, and discuss how this modification affects both the polarization distribution in ferroelectric thin films and the electron density at the LAO/STO interface. The importance of including the depolarizing field when modelling spatially inhomogeneous ferroelectric systems is also explored. Author Keywords: ferroelectric thin film, lanthanum aluminate, strontium titanate, transverse Ising model, two-dimensional electron gas
Support Vector Machines for Automated Galaxy Classification
Support Vector Machines (SVMs) are a deterministic, supervised machine learning algorithm that have been successfully applied to many areas of research. They are heavily grounded in mathematical theory and are effective at processing high-dimensional data. This thesis models a variety of galaxy classification tasks using SVMs and data from the Galaxy Zoo 2 project. SVM parameters were tuned in parallel using resources from Compute Canada, and a total of four experiments were completed to determine if invariance training and ensembles can be utilized to improve classification performance. It was found that SVMs performed well at many of the galaxy classification tasks examined, and the additional techniques explored did not provide a considerable improvement. Author Keywords: Compute Canada, Kernel, SDSS, SHARCNET, Support Vector Machine, SVM
Question of Space
Chultuns are subterranean chambers that are found throughout the Maya area. The purpose of this thesis is to provide further insight into the function of chultuns, specifically within the area of the Southern Maya Lowlands. Within the Northern Lowlands, the Pre-Columbian Maya used chultuns for water storage, but this function does not appear to be as prevalent within the Southern Lowlands Through reviewing published literature and first-hand excavation, a total of 332 chultuns located with the specified area were catalogued into a database. Based on the information obtained from the research, this thesis has identified the most frequent final function of chultuns, if there is chronological change in final functions of chultuns, and if there is regional change in final functions of chultuns. Author Keywords: burial, chultuns, Maya, ritual, Southern Lowlands, storage
Making eDNA count
Environmental DNA (eDNA) is rapidly becoming an established method for the detection of species in aquatic systems and has been suggested as a promising tool to estimate species abundance. However, the strength of the relationship between eDNA concentrations and taxon abundance (density/biomass) can vary widely between species. I investigated the relationship between eDNA concentration and species abundance using two common and closely-related amphibians in eastern North America, the wood frog (Rana sylvatica) and northern leopard frog (Rana pipiens). I manipulated tadpole density in 80 L mesocosms and documented the relationship between tadpole density, biomass, and eDNA concentration. Species were comparable in biomass but differed in the amount of detectible genetic material produced; density and biomass were the superior abundance metric correlated with eDNA concentration for wood frogs and leopard frogs, respectively. However, increases in eDNA concentration reflected increasing tadpole biomass, therefore biomass is likely a better metric of abundance than density. Overall my findings support that eDNA concentration can be used as an index of species abundance, but that species-specific calibration may be needed before eDNA concentration can be effectively translated to an abundance metric. Future research should refine our understanding of how biotic and abiotic factors influence eDNA production, degradation, and recovery across species, before the method can receive widespread use as a monitoring tool in natural settings. Author Keywords: abundance estimates, environmental DNA, mesocosm, Rana pipiens, Rana sylvatica
Observation-based assessment of atmospheric sulphur surrounding a major aluminum smelter in British Columbia, Canada
Recent developments at an aluminum (Al) smelter in Kitimat, BC resulted in a permitted increase of 27 to 42 tonnes of sulphur dioxide (SO2) emissions per day. Gaseous SO2 is a pollutant known to contribute to acidic deposition through processes of wet and dry deposition and can additionally react in-atmosphere to form particulate sulphate (pSO42-). Between June 2017 to October 2018, an extensive network consisting of ion exchange resin (IER) column, passive-diffusive, and active filter-pack samplers was established to provide an estimate of total annual S deposition and pSO42- variation throughout the Kitimat Valley. Filter-pack sampling determined the relative concentration of pSO42- increased downwind of the smelter. Comparison of observation-based and modelled total annual deposition suggested CALPUFF was accurate in representing the spatial viability of S deposition (R2 = > 0.85). However, the model appeared to overpredict near-field deposition suggesting the potential of underestimation further downwind of the smelter. Author Keywords: aluminum smelter, atmospheric deposition, filter-pack sampler, ion-exchange column sampler, pSO42-, SO2
Analyzing the Effectiveness of Social Movements Opposing Fossil Fuel Infrastructure
Blocking fossil fuel infrastructure projects like pipelines is increasingly being seen as a legitimate way for civil society groups to reduce global carbon emissions. This research project is an exploratory case study of the Trans Mountain pipeline in British Columbia and its opposition. My research question asks, ‘What has each tactic/strategy of opposition in the campaign to stop the Trans Mountain pipeline expansion accomplished, and how have they been effective? How can they be done more effectively?’ Through interviews and an autoethnography, my research explores the effectiveness of activists in this campaign. I analyze the results of my findings within social movement theory and other activist definitions of effectiveness from my literature review. The more significant findings from my research are that activists need to do a better job educating the public on the issue, need to direct more of their resources towards promoting a solution to the issue and make alliances with other movements and groups. This research project contributes to the literature on the effectiveness of oppositional strategies and tactics of pipeline resistance, as well as social movement theory. Author Keywords: British Columbia, pipeline, protest, strategy, tactic, Trans Mountain
Paleolandscape Reconstruction of Burleigh Bay, Ontario 12,600 cal BP to Present
This thesis presents a palaeotopographic reconstruction of the Burleigh Bay region of Stony Lake (Kawartha Lakes Region, Ontario) from 12,600 cal BP to present. The paleotopographic reconstructions are used to model paleoshoreline locations and archaeological site potential for the Late Paleoindian and early Archaic periods. Isostatic rebound following the end of the last glacial period has altered the topography in the region and water levels are now artificially managed by dams constructed in the 1830s. I completed a high-resolution bathymetric survey using a kayak equiped with a GPS coupled single-beam sonar. Utilizing GIS technology and isostatic rebound response surface models, I created paleotopographic reconstructions for 12,600 cal BP, 11,500 cal BP, 7,000 cal BP, 5,700 cal BP, and present. Results show that water levels in Burleigh Bay have been regressing over time until dam construction. Early site potential is centered in northern inland areas. Site potential following 7,000 cal BP is concentrated in northern areas flooded by the dam. Based on the reconstructions, surveys in lacustrine granite shield regions that follow the Ontario Standards and Guidelines for Consultant Archaeologists risk missing areas of high archaeological potential for early sites in these environments. Paleolandscape reconstructions would alleviate this issue by modeling paleoshoreline changes over time. Author Keywords: Canadian Shield, Early Archaic, Isostatic Rebound, Kawartha Lakes, Late Paleoindian, Paleolandscape
Sustainable Development and Environmental Security in the Canadian Arctic
This study identifies and examines interlinkages between climate change and sustainable development, environmental security, and adaptive capacity through a case study of two communities in the Inuvialuit Settlement Region: Inuvik and Tuktoyaktuk. It seeks to understand how these two communities perceive climate change and define sustainable development, particularly in relation to oil and gas development. This thesis discusses the constraints that may be arising for local communities to benefit from emerging opportunities due to competing notions of sustainable development and environmental security. The findings indicate how notions of environmental security and sustainable development act upon multiple levels to impact the adaptive capacity of communities in the Arctic. The general findings also suggest that regionally specific understandings of sustainable development, sustainability, and environmental security need to be acknowledged in order to develop successful governance coordination and cooperation strategies and paradigms related to economic, social, infrastructure and environmental issues in the NWT and the Canadian Arctic. Author Keywords: Arctic, Beaufort Sea, climate change, Environmental Security, Inuvialuit, Sustainable Development
Lives of Young Deliquents
The Royal Philanthropic Society (RPS) was the first institution in England to care for young offenders. While historians have demonstrated the legal importance of this institution, none have examined the experience of the youths it attempted to reform. The admission registers of the RPS reveal the importance of adults and peers in the experiences of the inmates of the institution, as both could be sources of conflict and support. Youths could express power over their own lives by resisting the authority of adults, but also by conforming to the rules of the RPS. Inmates could restrict the choices of their peers by working with the RPS, but also through peer pressure or violence. Networks of collaboration and youth culture could also exert a positive impact on peers. Because this thesis represents male youths as actors, it makes a significant addition to recent histories emphasizing the impact of the subaltern groups on eighteenth-century reform movements. Author Keywords: Conformity, Juvenile Delinquency, Penal Reform, Power Relationships, Royal Philanthropic Society, Youth Culutre

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