Graduate Theses & Dissertations

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UV-Curable hybrid sol-gel materials
This thesis describes the synthesis, application and evaluation of a UV crosslinked 3-methacryloxypropyltrimethoxysilane-derived coating formulation. This is a two-component sol-gel system with 3-methacryloxypropyltrimethoxysilane (MaPTMS) and tetraethoxysilane (TEOS). Herein we show that if we change the co-solvent required for solubilizing MaPTMS from the more common methanol and ethanol to isopropanol we change the rate of hydrolysis from days or weeks to minutes. With the assistance of 2D 29Si-NMR we demonstrate that the system undergoes extensive condensation in twenty minutes. Using standard UV irradiation, the material can be extensively UV crosslinked with 70% of the methacryloxy functionality being consumed in 5 minutes upon irradiation in the presence of a photo-initiator. When this material is used to coat low carbon steel and immersed in an accelerated corrosion solution (dilute Harrison’s solution); this material affords low carbon steel 25 hours of protection when crosslinked and 17 hours of protection when uncrosslinked. The material was then used to encapsulate polyaniline (PANI), an intrinsic conductive polymer used in the corrosion protection of metal substrates. PANI has been encapsulated previously in sol-gel material, but due to the pH dependence of the solubility of PANI, it can not be encapsulated in more commonly chemically crosslinked sol-gel. As our system is UV crosslinked rather than chemically crosslinked, we were able to successfully demonstrate the inclusion of PANI into our coating system. Finally, this thesis includes a thorough computational investigation into the structure and band gap of PANI. Through the analysis of the band gap it was shown that the structure of the polymer commonly displayed in literature is not the correct structure of the polymer. Our results suggest that when PANI is made electrochemically, the oligomer contains two quinoid units next to one another instead of the more usually represented regularly alternating benzoid and quinoid units. The results also suggest that when PANI is made using the oxidant ammonium persulfate, the polymer most likely contains a Michael adduct structure somewhere in the polymer chain which dominates PANI’s electronic properties. Author Keywords: 3-Methacryloxypropyltrimethoxysilane, Computational Chemistry , Corrosion , Polyaniline, Tetraethoxysilane
USE OF SALIVARY CORTISOL TO EVALUATE THE INFLUENCE OF RIDES ON THE STRESS PHYSIOLOGY OF DROMEDARY CAMELS (CAMELUS DROMEDARIUS)
Many facilities attempt to alleviate the risk of chronic stress in captivity by providing environmental enrichment shown to minimize behavioural disorders and stress in several species. One potential form of enrichment used in zoos is training animals to perform rides for guests, however, the effect of this activity on the welfare of individual animals has never been examined. I validated the use of saliva for assessing stress in dromedary camels (Camelus dromedarius) an animal commonly used for rides. I then measured variation in salivary cortisol in four male camels during animal rides for guests at the Toronto Zoo. The camels were sampled during the ride season (from June to August) using four treatments: 1) in their pasture, 2) at the ride area not performing rides, 3) performing a low number of rides (n=50/day) and 4) performing a high number of rides (n=150/day). Furthermore, samples were taken before and after the ride season for comparison. There was a significant difference between the post-ride season treatment and the three treatments involving guest presence during the ride season (ride area, low rides, high rides. This indicates that performing rides is not a stressful experience based on the stress metrics I used, and suggests that rides may be a form of enrichment for dromedary camels. Author Keywords: ACTH challenge, animal welfare, camels, environmental enrichment, salivary cortisol, stress
Tłı̨chǫ, Co-management and the Bathurst Caribou Herd, 2009-2011
Since time immemorial caribou have been and remain central to Tłı̨chǫ life and culture. As early as the late 19th century, Canada began to implement wildlife management policies in the NWT in response to concern over the health and future of caribou populations. However, the 2005 Tłı̨chǫ Land Claims and Self-Government Agreement (Tłı̨chǫ Agreement) signed by the Tłı̨chǫ, the Government of the Northwest Territories and the Canadian Government outlines that Tłı̨chǫ will have a say in wildlife management on Tłı̨chǫ Lands. Co-management is the power-sharing model used in an effort to ensure that the Tłı̨chǫ voice is heard in these decisions. My thesis centres on the 2009-2011 co-management process and the resulting final management decisions regarding monitoring and management actions to promote the stabilization and recovery of the Bathurst Caribou herd. I focus my analysis on the Tłı̨chǫ perspective as expressed during this co-management process. I conclude that while Tłı̨chǫ perspectives were presented in the hearings and related processes, they were not well represented in the final management actions. This omission speaks to the wider issue of how aboriginal people are treated and understood in Canada. Author Keywords: Canada, Caribou, Co-management, Northwest Territories, Tłı̨chǫ
Transcendental Turn
This dissertation traces the concept of transcendentalism from Kant's Critique of Pure Reason (1781) to Michel Foucault's historical a priori and Pierre Bourdieu's field and habitus, with implicit reference to Deleuze's `transcendental empiricism,' and the influence this trajectory has had on contemporary theory and culture. This general conceptual framework is used as the basis for a critical analysis of a series of examples taken from popular culture to highlight their transcendental conditions of possibility and the influence this conceptual paradigm has had on today's theory. The examples include the NFL `concussion crisis,' South Park's problematization of the discourse surrounding it, as well as the literature of Charles Bukowski, as an exemplification of an immanent writer-written situation. It is further suggested that, not only is transcendentalism an epistemological framework for thought, but it also doubles as an ontological principle for the emergence of a constitutively incomplete and unfinished reality. Author Keywords: Bukowski, Concussion, Foucault, Kant, South Park, transcendental
Tracking Mercury and Mercury Stable Isotopes Throughout the Wabigoon/English River System
In the Wabigoon/English River system, mercury concentrations downstream from Dryden, ON, where there was a former chlor-alkali plant, remain elevated in sediments and biota. Understanding the current extent and severity of mercury contamination downstream from the former chlor-alkali plant is of great interest in furthering the clean-up of mercury within the traditional territory of Asubpeeschoseewagong Netum (Grassy Narrows) First Nation. The objective of this study was to evaluate the current level and extent of mercury contamination within sediments, crayfish, Hexagenia mayflies, yellow perch, spottail shiner and walleye in the Wabigoon/English River system. An additional objective was to use mercury stable isotope analysis to distinguish between legacy mercury from the former chlor-alkali plant and mercury from geogenic sources. Mercury contamination within surface sediments and biota at locations as far as 178 kms downstream of the historical source of mercury contamination are elevated relative to the reference lake, Wabigoon Lake. Isotope ratios in young of the year fish and sediments collected from within the system were distinct from fish from the reference lake, Wabigoon Lake, indicating that anthropogenic mercury contamination is distinguishable from geogenic mercury. Author Keywords:
Trace Metal Geochemistry in Peatlands
Peatlands can be found widely across all latitudes and play a significant role in global cycles within the earth’s biosphere. The anoxic conditions in peatlands promotes the accumulation of organic matter through decreased rates of decomposition and the storage of certain elements, which have received contaminant loading over the course of human existence, with significant increases occurring during the period of industrialization. We assessed global patterns of metal enrichment in peatlands in 439 cores distributed across 5 continents and 21 countries and measured 35 elements by depth increments and by peatland type. Global patterns in enrichment factors (EF’s) were determined for all metals with the majority of metals being found to have a median EF < 2 indicating relatively minor enrichment. Principal component analysis indicated EF’s of 6 metals (Cd, Co, Cu, Ni, Pb, and Zn), 2 metalloids (As and Sb) and Se in the upper peat horizon had similar spatial patterns among peatlands and these elements had generally the highest EF’s with many cores exceeding EF >10 and some having EF values >100. Significant differences in EF’s were found for these 9 “pollution” elements by peatland type and to a greater extent by geographic region, with higher EF values typically occurring in Europe and North America. Enrichment factors for most elements exhibited weak but significant positive correlations with modelled [1850 – present] S deposition. Estimated pools for the “pollution metals” within the 0 - 40 cm depth varied considerably, with median global pools in peat ranging from 12.9 mg m-2 (Sb) to 439 mg m-2 (Zn) for these 9 metals. Climate changes presents a significant risk to global peatland geochemistry due to expected changes in hydrologic regimes, resulting in potentially increased metal mobility though drought-induced peatland acidification, with historic areas previously impacted by industrial activities presenting the greatest risk of metal release to downstream receiving environments. Using a case study, we examined the impact of simulated 30-day drought on pore water chemistry at six sites in a peatland complex in Elliot Lake Ontario that were historically impacted by uranium (U) mining activities. All sites responded similarly to simulated drought with pore water pH significantly declining. The decline in pore water pH was likely due to increasing sulphate (SO42-) concentrations, which accompanied large increases in Al, Ni, Cu, Pb, Zn, and U. Dissolved organic carbon (DOC) increased, which may further enhance Al, Cu, and U mobility as these metals are strongly complexed by organic acids. Metal partitioning (Kd) values could be significantly predicted by pH and DOC although the strength of the relationship varied considerably among sites. Multiple linear regression and the inclusion of SO4-2 improved predictions, indicating that declines in pH as a result of SO4-2 and H+ production primarily governs metals and U partitioning in peatland soils. The results from both studies show that metal enrichment in global peatlands is highly variable, with northern peatlands in industrialized areas presenting the greatest risk of metal release to downstream surface waters based on expected hydrologic impacts from climate change due to historical and on-going metal and S deposition. Author Keywords: Acidification, Climate Change, Drought, Enrichment Factors, Global, Peatlands
Towards a Critical Pedagogy of Globality
In this thesis, I use “Trump’s Wall” between Mexico and the US to resist Eurocentrism and the challenges Eurocentric pedagogy poses to the research-practitioner. In my method, I reimagine C. Alejandra Elenes’ borderlands theory as a zone of empowerment within a multicultural Canadian classroom, and braid it in a hybrid assemblage with the rhizome. The “rhizo-borderlands” assemblage uses selected field notes gleaned from my teaching practice to develop themes of a critical pedagogy of globality in personal, local and international dimensions. These are further braided with a “day-in-the-life” narrative of a fictionalized student (Ellie) who navigates her way towards a world literature classroom where the focus is The Kite Runner by Khaled Hosseini. This assemblage affirms my belief that teaching and learning provides a context where students become “border crossers” and navigate points of intersection between their local and global selves, in order to develop intercultural competencies. Author Keywords: Action Narrative, Critical Pedagogy, Rhizomes
Tourism Around Yellowknife
Yellowknife, which began as a gold-mining town in the 1930s, developed into a modern city and the territorial capital. Yellowknife is a popular destination for tourism with yearly growing numbers that reflect aurora viewers, business travel, general touring and visiting friends and relatives. Consequently, tourism in the Yellowknife area is increasing in volume and is of growing economic significance. Municipal and territorial governments actively advance its expansion, with the City’s 2015-2019 Tourism Strategy directed at infrastructure and service enhancement. While diamond tourism, as envisioned in 2004, did not progress, the Indigenous population in the territory is developing and executing community-based tourism plans. Utilizing Grounded Theory, this study demonstrates that governmental and stakeholder support proves dedication and commitment to the local tourism industry for years into the future. Yellowknife and its citizens take firm measures to attract increasing numbers of visitors in recognition of the value of tourism to their community. Author Keywords: Aurora borealis, Diamond industry, Government involvement, Northwest Territories economy, Tourism, Yellowknife
Tools and Techniques
The tools and techniques used by Ontario’s Middle Woodland potters to create designs on vessels have often been assumed in the literature. Pottery typologies currently use these assumptions to classify ceramics found in the archaeological record. Assumed, or suggested, tools and techniques include cord impression, cord-wrapped stick, fabric impression, fabric-wrapped paddle, incised paddles, unmodified shell, modified shell dentate tools, and leather thong. This thesis presents a series of experiments using replica versions of these tools. The results reveal that they are all viable tools for creating designs during ceramic manufacture. Specifically, incised paddles may have been used to create check-stamped pottery, unmodified shell may have been to create what the literature calls pseudo-scallop shell impressions, and modified shell may have been used to create what the literature calls dentate impressions. Where possible, experimental tiles were compared with examples from the Charleston Lake collection of complete to near complete Middle and Late Woodland vessels from Southeastern Ontario. These comparisons have revealed problems in the current classification and study of the Charleston Lake collection and a need for a re-evaluation of the current typologies used to classify Middle Woodland pottery Author Keywords: ceramic manufacture, cord-wrapped stick, experimental archaeology, Middle Woodland, point peninsula, pseudo scallop shell
Tool-use and near-tool effects
After active tool-use visual stimuli near a tool are processed more quickly and accurately than those farther away from a tool. Can these near-tool effects be modulated by training demands? To investigate this we asked the participants to complete a tool training task followed by a cross-modal interference task. During the training task the participants performed quick and accurate pointing movements to reach a strict or moderate criterion. The results indicated that the strict group made faster movements than the moderate group. During the cross-modal interference task visual distractors were presented along handheld tools in conjunction with vibrotactile stimuli on the hand. No significant compatibility effects were found for visual distractors near the hand or tool tip, and no consistent group differences were found. Our findings demonstrate the importance of using a novel tool during training, and that virtual stimuli may not be effective to elicit near-tool effects. Author Keywords: bimodal neurons, cross-modal interference, near-tool effects, tool training, training demands
To be kind or not to be kind
Past research suggests that students who are more academically resourceful tend to attain higher grades and feel more socially and academically adjusted at university. These same studies also show that students’ general resourcefulness and academic self-efficacy are strong, positive and direct predictors of their academic resourcefulness. My thesis expands upon this line of research by investigating the six dimensions of self-compassion (i.e., self-kindness, common humanity, mindfulness, self-criticism, isolation, over-identification) within the framework of the academic self-control model. In Study 1, a mixed methods approach was used, whereby after completing a measure on general learned resourcefulness, 20 students were interviewed to describe in detail their experiences with academic success and failure. Across the continuum of resourcefulness, interviews were analyzed for usage of self-compassion, academic resourcefulness, and explanatory style. Four themes emerged illustrating, compared to the highly resourceful students, the less resourceful students demonstrated fewer instances of academically resourceful behaviour, believed academic successes should require little effort, focused on the product of getting a high grade versus the process, and were less socially adjusted and mindful, and more isolated, ruminative, and overly self-critical when describing academic disappointments. Study 2 employed a correlational design to examine the relationships between the dimensions of self-compassion and the variables of the academic self-control model, with a sample of 196 students. As expected, the six dimensions of self-compassion were more strongly related to general resourcefulness than academic resourcefulness, with mindfulness and common humanity being unique predictors of the former variable. The contribution of the six dimensions to academic resourcefulness was shared with general resourcefulness and academic self-efficacy. The bivariate relationships between the dimensions of self-compassion and students’ grades were largely non-significant. Two dimensions uniquely predicted students’ adjustment to university – isolation and common humanity – alongside general and academic resourcefulness. In summary, the dimensions of self-compassion uniquely related to the more general measures of the model. Future research should explore the usefulness of an academic-specific measure of self-compassion in the prediction of academic resourcefulness, explanatory style, and grades. Whether including training on how to be more self-compassionate, in conjunction with teaching resourcefulness strategies, is beneficial for students is discussed. Author Keywords: academic resourcefulness, adjustment, explanatory style, general learned resourcefulness, self-compassion, self-efficacy

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Format: 2024/03/29