Graduate Theses & Dissertations


Relationships between Dissolved Organic Matter and Vanadium Speciation in the Churchill River, MB and the Mackenzie River Basin, NWT using diffusive gradients in thin films (DGT)
This study examines the influence of dissolved organic matter (DOM) on dissolved vanadium (V) speciation in the Churchill River and Great Slave Lake using diffusive gradients in thin film (DGT). Vanadium is commonly found in natural environments such as rivers, lakes and oceans. It regulates normal cell growth, but in excessive amounts, it can have toxic effects on human and aquatic organisms. The use of in situ, time integrated DGT devices allows to better (1) monitor the most bioavailable fraction of V, the DGT-labile V, in Arctic Rivers and (2) assess the influence of DOM on dissolved V speciation. Higher DGT-labile V was found in the the central regions of the Mackenzie River (MR), with an average of 7.7 ± 2.3 nM, likely due to sediment leaching and permafrost thawing. The Churchill River and Great Slave Lake (GSL) showed lower DGT-labile V levels (2.2 ± 1.6 nM and 3.6 ± 2.7 nM, respectively), compared to central regions in MR. The CR DGT-labile V concentrations was positively correlated to protein-like DOM concentration and abundance (r = 0.3, p < 0.05). The data collected from this study will help in developing new strategies regarding environmental health and impact assessments of environmentally hazardous waste that consist of potentially high levels of toxic vanadium species. Developments in the use of DGT devices as a sampling method will also aid in future studies involved in analyzing environmental health and specifically dissolved V species in natural waters. Author Keywords: diffusive gradients in thin-films, dissolved organic matter, fluorescence, mass spectrometry, UV-Vis, vanadium
Comparative Studies in Tropical Epicentres in Southeast Asia
From ca. 800-1400 CE, low-density agrarian states dominated Southeast Asia, their authority emanating from their epicentres at places such as Angkor in Cambodia, Bagan in Myanmar, and Sukhothai in Thailand. These epicentres were the setting for numerous structures, activities, and stakeholders that became integral for the perpetuation of the state. These states and their epicentres declined and collapsed around the same time. As part of a larger project (the Socio-ecological Entanglement in Tropical Societies (SETS Project), the aim of this thesis is to add to our understanding of entanglement, resilience, and collapse in Southeast Asia. Using a relatively new method that combines resilience and entanglement theories, this thesis presents a view of epicentral entanglements and vulnerabilities that eventually contributed to the collapse of these societies. The results indicate that overextended socio-ecological systems and their growing entanglements created a loss of resilience and, when faced with change in these systems, collapse. Author Keywords: Angkor, Bagan, Entanglement Theory, Resilience Theory, Southeast Asia, Sukhothai
Nymphs, Satyrs and Impotent Old Men
British pornographic texts arguing the texts were part of a wider cultural discourse on luxury, criticising the upper echelons of society for their decadent and vice-ridden lifestyles. Pornographic texts consistently portray the elites of Britain as partaking in sexual deviances including lesbianism, sex with dolls, dildos and household objects. The portrayals could be dismissed as tales fabricated for the titillation of the reading audience except that medical texts of the period diagnose the diseases of nymphomania and satyriasis, the rough equivalent of modern sexual addiction, as primarily affecting those of the upper class. Lifestyle was the key to diagnosis; luxurious living was thought to weaken the elite body rendering it vulnerable to excess sexual passions. Therefore, the hyper-sexual elite in pornographic texts reflected the contemporary cultural understandings of lifestyle and physiology. Author Keywords: Britain, culture, eighteenth century, nymphomania, pornography, sexuality
Memorable Movie Watching
Memorable Movie Watching: Viewer Ruminations about Memory in Four Canadian Films and their IMDb User Reviews explores how four Canadian films released in the decade around the turn of the millennium tell stories of memory and remembering, and how User Reviewers writing on the engage with, respond to, and re–remember those narratives filtered through their own remembered personal experiences. It embraces a new form of audience research by analyzing films alongside voluntary viewer contributions in order to bring these viewers’ voices into the conversation about memory in film and specifically Canadian film.Lilies (John Greyson, 1996), The Hanging Garden (Thom Fitzgerald, 1997), Marion Bridge (Wiebke Von Carolsfeld, 2002), and My Winnipeg (Guy Maddin, 2007) are each fiction films that focus on the main character’s deeply personal childhood memories. A textual analysis of the four films reveals trends in how the filmmakers create memory explorations and memory works [works based on memory] in Canadian film. A further textual and thematic analysis of the IMDb’s 117 User Reviews for these four films reveals how viewers engage with what I term memory narratives and the personal memories these films spark. The four films respectively privilege, through narrative and filmic techniques, each protagonist’s telling of remembered childhood events. Yet when User Reviewers of the films comment on the protagonist’s remembered childhood events, they choose to contest them, citing the unreliability of the remembered and of memory itself. User Reviewers interrogate the film narratives against their own personal experience, all the while asserting that there is significance to be found in the process of remembering. For User Reviewers, this process of remembering involves engaging with the film and then writing about their memories of watching the film and its narrative through their own sparked memories. In this process, they dig for significant meaning even though Users rarely articulate that meaning or specify for whom it is meaningful. In their writing, Users do reveal their own thoughts and beliefs about Canadian film, as well as their knowledge of filmmakers, related texts, Canadian locations, and their own childhood and youth experiences. Key words Memory, Remembering, Canadian Film, User generated content, Audience, Viewer, Thom Fitzgerald, John Greyson, Guy Maddin, Wiebke von Carolsfeld Content Warning Please note: the memory stories depicted in these films, discussed in the User Reviews and in this dissertation are extremely disturbing and may be upsetting to the reader. Author Keywords: Audience, Canadian Film, Memory, Social Media, User Generated Content, Viewer
Changes in Forms of Uranium in Anoxic Lake Sediments and Porewaters Near an Abandoned Uranium Mine, Bancroft, Ontario
Soluble uranium (U) has been observed continuously in the porewaters of Bentley Lake, a lake with semi-permanent anoxic sediments, despite the fact that reduced U(IV) is known to be insoluble. To be able to predict the fate and mobility of U that has been deposited in lake sediments, it is very important to understand the factors that determine soluble uranium in anoxic environments. Understanding soluble U species is crucial for predicting its behavior in natural systems as well as for the development of U remediation schemes. To explore the factors affecting soluble U in natural environments, anoxic lake sediments and porewaters were tested using two analytic methods, ICP-MS and ESI-HR-MS. Reduced uranium (U(IV)) can be precipitated as U(IV)-NdF3. Using this method revealed that most of the uranium in porewater is not able to be co-precipitated with NdF3. In addition, UO2+ was found using ESI-HR-MS, showing uranyl ions exist in reduced porewater. However, the UO2+ might be attached to some organic groups rather than present as free ions. Seasonal variation and air exposure experiments on the mobility of U between sediments and porewater were observed to test for changes of the redox state of U as a function of sample collection and storage. The results of this study will contribute to better remediation strategies for U tailings and will help U mining operations in the future. Author Keywords:
Augmented Reality Sandbox (Aeolian Box)
The AeolianBox is an educational and presentation tool extended in this thesis to represent the atmospheric boundary layer (ABL) flow over a deformable surface in the sandbox. It is a hybrid hardware cum mathematical model which helps users to visually, interactively and spatially fathom the natural laws governing ABL airflow. The AeolianBox uses a Kinect V1 camera and a short focal length projector to capture the Digital Elevation Model (DEM) of the topography within the sandbox. The captured DEM is used to generate a Computational Fluid Dynamics (CFD) model and project the ABL flow back onto the surface topography within the sandbox. AeolianBox is designed to be used in a classroom setting. This requires a low time cost for the ABL flow simulation to keep the students engaged in the classroom. Thus, the process of DEM capture and CFD modelling were investigated to lower the time cost while maintaining key features of the ABL flow structure. A mesh-time sensitivity analysis was also conducted to investigate the tradeoff between the number of cells inside the mesh and time cost for both meshing process and CFD modelling. This allows the user to make an informed decision regarding the level of detail desired in the ABL flow structure by changing the number of cells in the mesh. There are infinite possible surface topographies which can be created by molding sand inside the sandbox. Therefore, in addition to keeping the time cost low while maintaining key features of the ABL flow structure, the meshing process and CFD modelling are required to be robust to variety of different surface topographies. To achieve these research objectives, in this thesis, parametrization is done for meshing process and CFD modelling. The accuracy of the CFD model for ABL flow used in the AeolianBox was qualitatively validated with airflow profiles captured in the Trent Environmental Wind Tunnel (TEWT) at Trent University using the Laser Doppler Anemometer (LDA). Three simple geometries namely a hemisphere, cube and a ridge were selected since they are well studied in academia. The CFD model was scaled to the dimensions of the grid where the airflow was captured in TEWT. The boundary conditions were also kept the same as the model used in the AeolianBox. The ABL flow is simulated by using software like OpenFoam and Paraview to build and visualize a CFD model. The AeolianBox is interactive and capable of detecting hands using the Kinect camera which allows a user to interact and change the topography of the sandbox in real time. The AeolianBox’s software built for this thesis uses only opensource tools and is accessible to anyone with an existing hardware model of its predecessors. Author Keywords: Augmented Reality, Computational Fluid Dynamics, Kinect Projector Calibration, OpenFoam, Paraview
Cognitive Inefficiencies in Adolescents with Eating Disorders
Eating Disorders (ED) are notoriously difficult to treat due, in part, to commonly observed inefficiencies in cognitive flexibility and central coherence, which are believed to maintain disordered cognitions and behaviours and negatively impact prognosis. Cognitive remediation therapy (CRT) has recently been used effectively with adults with ED; however, evidence among adolescents is limited. The present study explored change in flexibility and central coherence in a group of 23 adolescent ED inpatients (M = 16 years, SD = 0.95). All participants received a comparable dose of ED treatment. Participants were split into two groups for comparison: the CRT group (n = 15) received CRT in addition to TAU; and a TAU group for control (TAU; n = 8). Improvements in flexibility and central coherence were superior in the CRT group, suggesting that CRT is a potentially useful treatment for adolescents with AN as part of an overall psychosocial rehabilitation program. Author Keywords: anorexia nervosa, central coherence, cognitive flexibility, cognitive remediation, eating disorders, set shifting
Potential Contribution of Mobile Processing Services to Food System Sustainability in the Regional Livestock Production Industry of Central Ontario
This qualitative study examines the applicability, impact, best practices, sustainability and livestock welfare implications of mobile processing service operation in central Ontario. Grounded theory concepts were utilized to analyze data generated from semi-structured interviews and a community focus group, supplemented by an initial exploratory literature review, and focused review approach to refine emergent categories. It was found that there is interest in, applicability for, and food system-sustainability benefit from mobile processing services, but market competition and regulatory context impede the profitability of operation, not just for mobile service, but for existing provincial plants. Public support for mobile or regionalized processing resources could address many of the sustainability concerns in our regional livestock production and consumption systems, but where appetite for such political action does not exist, solutions are required if we hope to address the continuing centralization, commodification, traditional profit-maximization and negative externality generation of our industrialized agri-food production system. Author Keywords: agri-business production and distribution, livestock welfare, mobile abattoirs and livestock processing, regional food systems, rural-urban relations, sustainability
Application of Data Science to Paramedic Data
Paramedic data has significant potential for research. Paramedics see many patients every year and collect a wide variety of crucial data at each encounter. This data is rarely used for good reason: it’s messy and hard to work with. But like theunderdog character in a classic movie, with a little bit of work and a lot of understanding, paramedic data has significant potential to change the world of medical research. Paramedics throughout the world are involved in research every day, but most of this research uses purpose-built data structures and never takes advantage of the existing data that paramedics create as part of their everyday work. Through a project-based approach grounded in developing a better understanding of the opioid crisis, this thesis will examine the quantity and structure of the existing paramedic data, the complexities of its current design, the steps necessary to access it, and the processes necessary to clean existing data to a point where it can be easily modelled. Once we have our dataset, we will explore the challenges of choosing key metrics by examining the effectiveness of metrics currently employed to monitor the opioid crisis and the influences public health programs and changing policies have had on these metrics. Next, we will explore the temporal distributions of opioid and other intoxicant use with an eye to providing data to support public health in their harm reduction efforts. And lastly, we will look at the effect of fixed- and floating-point temporal influences on intoxicant-related calls with an eye to how these temporal points can affect call volumes. By using this exploration of the opioid crisis, this thesis will show that with a more thorough understanding of what paramedic data is, what data points are available, and the processes needed to transform it, paramedic data has the potential to greatly expand the limits of health care data science into a more precise and more all-encompassing discipline. Author Keywords: Ambulance, Data Science, Opioid, Overdose, Paramedic, Pre-hospital
Radiocarbon Analysis of the Middle to Late Woodland Transition in Southern Ontario
The goal of the thesis is to establish the temporal patterning of the cultural complexes of the Middle to Late Woodland periods in Ontario. To do so I examine the statistical shape and phase boundaries of samples of radiocarbon dates associated with the Princess Point, Sandbanks, Glen Meyer, and Pickering archaeological complexes. The radiocarbon dates used for this thesis were collected through published sources, grey literature, and resources such as the Canadian Archaeological Radiocarbon Database. Each date was put through a data hygiene process and those deemed acceptable were merged into Summed Probability Distributions (SPDs) and further analysed through the r-carbon and OxCal packages. Bayesian statistics were used to estimate the start and end dates per complex, Shapiro-Wilks tests were used to examine the legitimacy of cultural entities, and the amount of geographic, and chronological overlap was determined by randomly sampling between the compared datasets to determine an acceptable threshold of randomness. Results indicate that the Princess Point complex does not meet the requirements of a culturally homogeneous archaeological cultural group. There is no difference in the Glen Meyer and Pickering radiocarbon patterns, which supports combining them into a single cultural designation. It was impossible to evaluate the Sandbanks complex due to a lack of radiocarbon data, although overall it seems to agree with the current understanding of the complex. Author Keywords: Glen Meyer, Ontario Archaeology, Pickering, Princess Point, Radiocarbon, Sandbanks
Assessing habitat suitability and connectivity for an endangered salamander complex
Habitat loss and fragmentation have significantly contributed to amphibian population declines, globally. Evaluating the state of remaining habitat patches can prove to be beneficial in identifying areas to prioritize in conservation efforts. Pelee Island, Ontario is home to a complex of salamanders including small-mouthed salamanders (Ambystoma texanum), blue-spotted salamanders (A. laterale) and unisexual Ambystoma (small-mouthed salamander dependent population). These populations have declined from intense landscape changes since the late 1800s, particularly from the historical drainage of wetlands. In this thesis, I evaluated the suitability and connectivity of habitat patches occupied by these salamanders to assess the size of, and dispersal capabilities between, remaining habitat patches. I found that there was a low amount of suitable terrestrial habitat available for this complex of salamanders, and existing habitat patches were small and isolated. Forested areas and non-breeding wetlands were considered to be suitable habitat when adjacent to existing breeding locations, suggesting that these habitats should be a focus for conservation efforts. Notably, intervention may be necessary to maintain this amphibian complex as many assemblages are isolated from one another and potential corridors currently consist of primarily unsuitable habitat. Given that much of the salamander complex is reliant on one species for reproduction, the long-term viability of this population of Ambystoma salamanders may rely on the enhancement of suitable habitat near current breeding sites by conservation organizations and local stakeholders. Ultimately, the approach used in this thesis emphasizes the value of evaluating habitat within a fragmented landscape to focus conservation efforts on imperilled species. Author Keywords: amphibians, connectivity, habitat suitability, landscape fragmentation, landscape resistance, unisexual
Postclassic Maya Diet
Postclassic (AD 900-1500) Maya diet at Ka’kabish, Belize was examined using stable carbon and nitrogen isotope analysis of human bone collagen, and stable carbon isotope analysis of bone structural carbonate. Isotope data were compared to skeletal and dental indicators of diet and disease, and dietary differences among burials excavated from chultuns (B-2, C-1, C-2, and C-3) at Ka’kabish. Varying in dimensions, chultuns are characterized as multiple subterranean chambers carved into limestone bedrock, where re-entry was permitted through the removal of a capstone placed over a circular entrance. Due to poor preservation and commingling of human remains, diet and its relation to age, sex, and social status could not be explored. The general diet at Ka’kabish is consistent with the consumption of a diverse range of terrestrial plants and animals, in addition to marine resources. Relative to the other chultun burials, Chultun C-2 is an outlier, with a noticeably different diet, evidence for skeletal pathology, and absence of dental modifications. This study demonstrates a lack of significant dietary differences among Postclassic Maya sites in northern Belize, along with an apparent reliance on marine resources, further supporting the notion of a close association, and equal participation in a regional trading system with coastal sites that allowed for populations in this region to thrive during the Postclassic period. Author Keywords: Ancient Maya, Bioarchaeology, Ka'kabish, Osteology, Postclassic, Stable Isotopes


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