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
Population-Level Ambient Pollution Exposure Proxies
The Air Health Trend Indicator (AHTI) is a joint Health Canada / Environment and Climate Change Canada initiative that seeks to model the Canadian national population health risk due to acute exposure to ambient air pollution. The common model in the field uses averages of local ambient air pollution monitors to produce a population-level exposure proxy variable. This method is applied to ozone, nitrogen dioxide, particulate matter, and other similar air pollutants. We examine the representative nature of these proxy averages on a large-scale Canadian data set, representing hundreds of monitors and dozens of city-level populations. The careful determination of temporal and spatial correlations between the disparate monitors allows for more precise estimation of population-level exposure, taking inspiration from the land-use regression models commonly used in geography. We conclude this work with an examination of the risk estimation differences between the original, simplistic population exposure metric and our new, revised metric. Author Keywords: Air Pollution, Population Health Risk, Spatial Process, Spatio-Temporal, Temporal Process, Time Series
Robust assessment of changes in wild mammal occupancy and activity relative to livestock and human disturbance
Anthropogenic activities such as human activity and livestock grazing are responsible for the global rise in disturbance impacts on wildlife and may underlie regional changes in biodiversity and ecosystem dynamics. Few studies have tried to disentangle the effects of different anthropogenic activities on wildlife behaviour, leaving a major gap in our understanding of conservation and management needs in disturbed areas. Human activity and livestock grazing are increasing in spread and intensity worldwide, thereby imposing pressure on both wildlife and natural areas. In this thesis, I used a camera trapping and occupancy modeling framework to assess whether human presence and livestock grazing had different impacts on site occupancy and activity of 10 wild mammal species, and how responses differed across taxa. Specifically, I predicted that all species would be sensitive to disturbance, but the type and intensity of the response would depend on disturbance type. I detected different responses to each disturbance type across species, but response type (displacement, activity change, crepuscularity) was not associated with species characteristics such as body. Importantly, disturbance intensity had a strong effect on wildlife activity levels, with many species exhibiting marked reductions in activity at high human or livestock disturbance intensity. It remains unclear whether all species’ responses are a direct consequence of disturbance versus indirect outcomes of shifts in behaviour of other species in the wildlife community (i.e., disturbance-related changes in prey activity may affect predator activity). Although on the whole disturbance intensity and effect sizes tended to be relatively low in this study, responses were exhibited across all species, implying that disturbance responses may be universal in wild mammals and largely underestimated. Ultimately, my work offers a template for the robust assessment of disturbance impacts on wildlife and provides new avenues for future research to deepen our understanding of wildlife sensitivity to anthropogenic activities. Author Keywords: activity, anthropogenic disturbance, human activity, livestock, occupancy, wildlife
Differences and similarities in exploration and risk-taking behaviours of two Myotis bat species.
AbstractDifferences and similarities in exploration and risk-taking behaviours of two Myotis bat species. Laura Michele Scott Behaviours that are repeatable across circumstances and time determine an individual’s personality. Personality and behavioural variation are subject to selective pressures, including risks related to the use of different habitat types. I explored the ecological and evolutionary consequences of habitat selection by comparing the behaviour of two sympatric bat species, Myotis leibii and M. lucifugus. These species display overlap in roosting preferences, however, M. leibii tend to roost in crevices on the ground, while M. lucifugus tend to roost in crevices or cavities that are raised off the ground. I hypothesized that the habitat selection patterns of these two species create behavioural reaction norms at the species level. I predicted that ground roosting behaviour favours bolder personality and more exploratory and active traits when compared with bats that do not ground roost. I examined inter- and intra-specific variation in behaviour using a modified, three-dimensional open-field test and quantified the frequency and duration of behaviours such as flying, landing, and crawling. Bats were continuously video-recorded over 1-hour nocturnal and diurnal trials. I used a priori mixed models with combinations of individual characteristics and life-history traits to select the models that best describe each species. We found that M. leibii (n = 15) displayed more exploratory and bolder behaviours than M. lucifugus while on the ground (n = 21) and higher overall activity during the trial. I also found that M. leibii displayed crawling behaviours and movements consistent with foraging while on the ground which is a rare behaviour in bats and only observed in a few species (Desmodus rotundus and Mystacina tuberculate to my knowledge). Future research should explore biomechanical adaptations associated with ground-foraging in M. leibii. Author Keywords: Bats, Behaviour, Exploration, Myotis leibii, Myotis lucifugus, Roosting
Chew the Fat
Fatty acid analysis was performed on archaeological bone from various fauna from sites in the Canadian arctic to better understand the preservation of fatty acids and their potential applications to palaeoecological and palaeodietary studies. These data were complemented by analyses of modern bone and soft tissue samples from livestock and harp seals (Pagophilus groenlandicus). Results of modern analyses revealed that in terrestrial species, bone has inherently lower concentrations of most fatty acids relative to other soft tissues (adipose, marrow, and muscle). These analyses suggest that the distribution of fatty acids in bone is unique compared to other tissues, and the types and abundances of fatty acids in bone may be linked to dietary sources of lipids. Of the archaeological samples analyzed, terrestrial species (caribou [Rangifer tarandus]) generally exhibited higher concentrations of saturated fatty acids compared to marine species (ringed seals [Pusa hispida] and polar bears [Ursus maritimus]), whereas marine species had higher concentrations of monounsaturated fatty acids compared to terrestrial species. Results of analyses on both modern and archaeological samples provided insight into the degradation of fatty acids in bone, and the rapid loss of polyunsaturated fatty acids in particular. Because the abundances of fatty acids are likely altered in the burial environment, it is recommended that future analyses incorporate compound specific isotope analysis to focus on applications of fatty acids that are typically in the highest abundance and arguably have undergone the least amount of change, including palmitic (C16:0) and stearic acid (C18:0) Author Keywords: Archaeological Science, Bone Lipids, Fatty Acid Analysis, GC-MS, Lipid Preservation, Palaeoecology
knight and his horse
This thesis examines the social impact of horses on French elites between 1150 and 1300. Using courtly literature, a veterinary treatise, manuscript illuminations, archeological studies, material artefacts, and account books, it explores the place of horses in elite society—practical and symbolic—and assesses the social costs of elite use and ownership of horses. While horses served practical functions for elites, their use and investment in horses clearly went far beyond practicality, since elites used horses recreationally and sought prestigious horses and highly decorated equipment. Their owners used horses in displays of power, status, and wealth, as well as in displays of conspicuous consumption and the performance of gender roles. The social display associated with horses was integrally tied to the ideology and performance of chivalry. This study examines the broader use of horses by elites to understand their place in the elite culture of the High Middle Ages. Author Keywords: Horses, Knighthood, Medieval France, Military History, Nobility, Social History
Conservation genetics of Redside Dace (Clinostomus elongatus)
Recent range reductions of endangered species have been linked to urban development, increased agricultural activities, and introduction of non-native species. I used Redside Dace (Clinostomus elongatus) as a focal species to examine the utility of novel monitoring approaches, and to understand historical and contemporary processes that have influenced their present distribution. I tested the efficacy of environmental DNA (eDNA) to detect Redside Dace, and showed that eDNA was more sensitive for detecting species presence than traditional electrofishing. Parameters such as season, number of replicates, and spatial versus temporal sampling need to be accounted for when designing an eDNA monitoring program, as they influence detection effectiveness and power. I also assessed the species’ phylogeographic structure using both mitochondrial and microsatellite DNA analysis. The data from the microsatellite markers indicate that Redside Dace populations are genetically structured, with the exception of several populations from the Allegheny River basin. Combined sequence data from three mitochondrial genes (cytochrome b, ATPase 6 and ATPase 8) indicated that Redside Dace persisted within three Mississippian refugia during the last glaciation. Secondary contact between two lineages was indicated by both mitochondrial and microsatellite data. The combined results from the eDNA and conservation genetics studies can be used to inform Redside Dace recovery efforts, and provide a template for similar efforts for other aquatic endangered species. Author Keywords: eDNA, endangered, genetics, phylogeography
Assessing Measured and Perceived Risks to Drinking Water Sources
Microcontaminants originating from wastewater effluent and run-off from agricultural lands may be present in the sources of drinking water for rural and Indigenous communities in mixed-use watersheds. In this study, a convergent parallel mixed-methods design was applied to assess measured and perceived risks of contamination in the sources of drinking water for two communities; the Six Nations of the Grand River community in Ontario and the community of Soufriere in St. Lucia, West Indies. The overall goal of the project was to assess how measured and perceived risks of exposure to chemical and biological contaminants in drinking water sources could inform water management strategies for the communities. Quantitative data obtained from the analysis of water samples collected indicated that the highest levels and occurrence of fecal bacteria were found in the Soufriere watershed while the highest concentrations and occurrence of pesticides were found in the Grand River watershed. In the Grand River watershed, conventional treatment of water followed by activated carbon filtration and UV disinfection removed fecal bacteria and also removed many chemical microcontaminants with efficiencies as high as 98%. Data from both watersheds indicated that there was a strong positive correlation between the levels of caffeine and sucralose (i.e. indicators of wastewater contamination) in water samples and the levels of either Total Coliforms or fecal bacteria of human origin. Human health risk assessments of individual pesticides and pesticide mixtures performed by applying a hazard quotient (HQ) and hazard index (HI) model, respectively indicated that there were no apparent risks to human health from those microcontaminants. Qualitative data obtained from face-to-face interviews with water managers and health professionals working in the two communities, which were collected and analysed concurrently but independently, illustrated that there were cross-cultural similarities and differences in factors influencing the perceptions of risks associated with the sources of drinking water. These perceptions of risks were mainly influenced by factors such as heuristics or informal and informal reasoning, cognitive-affective factors, social-political institutions and cultural factors. These factors may have also influenced water managers and health professionals, as they often recommended more “soft” strategies for managing water resources in the communities. Key words: pesticides, fecal bacteria, microcontaminants, POCIS, measured risks, perceived risks, water management, First Nations, Grand River, Soufriere, St. Lucia Author Keywords: fecal bacteria, measured risks, microcontaminants, perceived risks, POCIS, water management
Assessing effects and fate of environmental contaminants in invasive, native, and endangered macrophytes
Macrophytes play an important role in aquatic ecosystems, and thus are integral to ecological risk assessments of environmental contaminants. In this dissertation, I address gaps in the assessments of contaminant fate and effects in macrophytes, with focus on glyphosate herbicide use for invasive plant control. First, I evaluated the suitability of Typha as future standard test species to represent emergent macrophytes in risk assessments. I concluded that Typha is ecologically relevant, straight-forward to grow, and its sensitivity can be assessed with various morphological and physiological endpoints. Second, I assessed effects from glyphosate (Roundup WeatherMAX® formulation) spray drift exposure on emergent non-target macrophytes. I performed toxicity tests with five taxa, Phragmites australis, Typha × glauca, Typha latifolia, Ammannia robusta, and Sida hermaphrodita, which in Canada collectively represent invasive, native, and endangered species. I found significant differences in glyphosate sensitivity among genera, and all species’ growth was adversely affected at concentrations as low as 0.1% (0.54 g/L), much below the currently used rate (5%, 27 g/L). Third, I assessed the potential for glyphosate accumulation in and release from treated plant tissues. I found that P. australis and T. × glauca accumulate glyphosate following spray treatment, and that accumulated glyphosate can leach out of treated plant tissues upon their submergence in water. Finally, I assessed effects of released glyphosate on non-target macrophytes. I found that P. australis and T. × glauca leachate containing glyphosate residues can stimulate the germination and seedling growth of T. latifolia, but can exert an inhibiting effect on A. robusta, although leachate without glyphosate caused similar responses in both plants. Additionally, I found no negative effects in A. robusta when exposed to glyphosate residues in surface water, or when grown with rhizosphere contact to an invasive plant that was wicked (touched) with glyphosate. My results show that non-target macrophytes can be at risk from glyphosate spray for invasive plant control, but risks can be mitigated through informed ecosystem management activities, such as targeted wick-applications or removing plant litter. Integrating contaminant fate and effect assessments with emergent macrophytes into ecological risk assessments can support the protection of diverse macrophyte communities. Author Keywords: Ecosystem management, Ecotoxicology, Glyphosate, Herbicide, Invasive plant, Species at risk
Academic Efficiency
Universities produce a significant and increasing share of basic research that is later commercialized by firms. We argue that the university's prominence as a producer of basic research is the result of a differential efficiency in research production that cannot be replicated by firms or individual agents - teaching. By using research accomplishments to signal knowledge and attract tuition-paying students, universities are uniquely positioned to undertake certain types of research projects. However, in a market for innovation without patent rights, a significant and increasing number of basic research projects, that are social welfare improving, cannot be initiated by firms or universities. The extension of patent rights to university-generated research elegantly redresses this issue and leaves us to ponder important questions about the future of our innovation-driven economies. Author Keywords: Innovation, Intellectual Property Rights, Research, Science Technology and Innovation Policy
Digital Elevation Models and Viewshed Analysis
This thesis approaches the issue of Viewshed Analysis and how it can impact the understanding of a medieval environment. Centered on the High Medieval period of Cilicia, in what is today Southwestern Turkey, the precision of Viewsheds in a complex terrain is evaluated, and the role of the fortifications in the environment is expanded upon. The maps that were generated for this thesis demonstrate that the use of free datasets must be done with caution, and that the use of more than one dataset is crucial in trying to create a clearer picture of the environment. The examination of four separate sets of fortifications within the region leads to new questions about the role of fortifications in the region, as well as a better understanding of what groups such as the Armenian Cilicians and the Knights Templar were doing in the High Medieval period. Finally, conclusions are made regarding the future impact of GIS based studies, and how they can help scholars understand Ancient and Medieval landscapes. Author Keywords: Armenian Cilicia, Fortifications, GIS, Viewshed
Anishinaabe Motherhood
The purpose of this qualitative study is to investigate Anishinaabe women’s Traditional Teachings and pedagogies in a contemporary context. Through this exploration, I have uncovered the tensions, challenges, and strengths that Anishinaabe gaashiyag (mothers) face when engaging with these Traditional Teachings and pedagogies. The research methodology I have used is a branch of grounded theory called the Anishinaabe Research Methodology, and it is integral to the Anishinaabe principles of living called the Seven Grandparent Teachings: Wisdom, Love, Respect, Bravery, Honesty, Humility, and Truth. I used a research method called the Nbwaachiwi (the art of visiting) method. I used the ‘Aunties kitchen table’ style of knowledge collection, where it is open-ended and one-on-one - like you would be at your auntie's kitchen table, sharing stories and having tea. By utilizing these principles, I conducted my research through the Anishinaabe-aadiziwin (culture and language – way of life) paradigm. I addressed multilayered Anishinaabe teachings and many connections to the land and spirituality. I have found that Anishinaabe gaashiyag feel pressure to adopt Western modes of raising their children. However, some young women are returning to the traditional Anishinaabe teachings by using traditional birthing techniques, tiknigaans (traditional baby carriers), and evolving our cultural practices to fit modern ways of living. The knowledge I present within this paper can inform mothers who want to learn Traditional Teachings and pedagogies, and thereby resist ongoing intergeneration trauma and colonization. New generations are identifying what the negative effects on raising Anishinaabe children and taking a stand to break ongoing trauma and abuse so that their children do not have to be subjected to it. These mothers are informed about cultural and Traditional Teachings with the hope that they can use this knowledge to assist them on their path to, and during, motherhood. Given the determination of these young mothers to raise their babies using Anishinaabe traditional methods, the future identities and lives of their children may be significantly better in a cultural sense than their predecessors. They will be the products of their mothers’ commitment to the resurgence of Anishinaabe maternal teachings and pedagogies. Author Keywords: Anishinaabe, Indigenous Motherhood, Motherhood, Parenting, Pedagogies, Teachings

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Format: 2024/02/20