Graduate Theses and Dissertations

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https://hdl.handle.net/10388/381

This collections holds all University of Saskatchewan graduate level electronic theses and dissertations (ETDs) published since 2005. More than 700 print theses published before 2005 have been digitized and added to the collection as well.

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Canadian Rural and Urban Older Adults: A Comparison of Functional Status
(2025-03-26) Hyde, Anne; Labreque, Mary Ellen; Szafron, Michael; Donna, Goodridge; Shelley, Peacock; Li, Hua; Martine, Puts; Roslyn, Compton
The abstract of this item is unavailable due to an embargo.
Exploring Access to Disease-Modifying Therapies and Support Services for People Living with Multiple Sclerosis in Saskatchewan
(2025-03-26) Pereira, Sarah Pinto; Spurr, Shelley; Vandenberg, Helen; Levin, Michael; Sattar, Schroder
Background: Saskatchewan has one of the highest global MS prevalence rates, with approximately 3,700 cases per 1.174 million people. In 2017, an integrated care pathway (ICP) was introduced to improve MS care delivery, but its effectiveness remains unclear. Given the importance of disease-modifying therapies (DMTs) in reducing disability progression and improving quality of life (QoL), patient access to DMTs and supportive care within the ICP context must be explored. Study Aim: This study aimed to: (1) examine accessibility to DMTs and essential DMT support services and resources in Saskatchewan. (2) explore the barriers of people with MS (Pw-MS) are facing in accessing these services and resources. (3) understand if access time to first DMT prescription and first DMT follow-up appointment was associated with the sociodemographic variables and self-reported QoL. Methods: A web-based exploratory descriptive survey was piloted among Pw-MS diagnosed between May 1, 2017, and January 1, 2020, and registered at the MS clinic. The survey included 26 sociodemographic/MS-related items and 40 items assessing access and barriers based on Levesque’s framework. Access was measured as time-to-prescription, time-to-follow-up, and a curated access survey. Descriptive and inferential statistics explored relationships between access times, sociodemographic factors, and QoL. Results: Sixty-eight participants (44 female, 24 male), mean age 35.81 (SD 10.20) at diagnosis, met inclusion criteria. ICP targets for prescription and follow-up were met, with access aligning with affordability, appropriateness, and acceptability. Barriers were noted in availability and patient perception. A significant negative correlation (p = .001) was found between time-to-DMT prescription and QoL, suggesting timely DMT access may improve QoL. Conclusion: An ICP for MS may enhance DMT access and supportive care, with early DMT initiation potentially linked to improved QoL.
Precision Calculations in Theoretical Particle Physics and the Search for New Physics
(2025-03-26) Li, Siyuan; Steele, Tom; Degenstein, Doug; Tanaka, Kaori; Lewis, Randy; Rayan, Steven; Dick, Rainer
In order to advance the understanding of fundamental particles and their interactions, precision is crucial in theoretical particle physics predictions. In quantum field theory and quantum chromodynamics (QCD), improving corrections beyond the leading order in both perturbative and non-perturbative contributions to observable quantities are key to improving theoretical results. We analyze higher-order contributions through various methodologies, such as QCD sum rules, on observables including the $2^{++}$ tensor di-gluonium two-point correlator and the hadronic vacuum polarization contributions to the muon anomalous magnetic moment. We also develop a numerical computational methodology using pySecDec, a Python-based package for the numerical calculation of dimensionally-regulated loop integrals, to evaluate loop integrals at finite temperature in the Matsubara formalism. This work refines calculational precision and scope, both phenomenologically and methodologically, to support the search for new physics phenomena.
New Graduate Nurses' Transition to Rural Emergency Practice: A Narrative Inquiry
(2025-03-21) Moon, Elizabeth M; Rohatinsky, Noelle; Penz, Kelly; Bigalky, Jodie
The ratio of Registered Nurses (RNs) to rural Canadians has declined over the past decade, resulting in an increased reliance on new graduate nurses (NGNs) in rural emergency departments (EDs). However, NGNs often enter the workforce unprepared for the acute and unpredictable nature of emergency care. The stress of transitioning to practice in such settings, combined with insufficient professional and emotional support, places NGNs at significant risk of job turnover. This perpetuates a cycle of nursing attrition, threatening rural Canadians’ access to quality healthcare. Despite the critical need for effective interventions to support NGNs in rural EDs, research on their experiences within this unique context is lacking. The purpose of this study was to explore the experiences of NGNs transitioning to professional practice in rural EDs, to contribute to the insight needed for the development of supportive interventions. The specific aims were to facilitate a deeper understanding of NGNs’ transition experiences, to examine the influence of the rural emergency context on their growth, explore their main challenges, and identify their unique support needs. These aims were guided by an evolving research puzzle that asked: How do NGNs experience the transition to practice in rural EDs? How does the rural emergency context shape their transition? Where do these NGNs encounter stress and growth, and what sources of support do they draw upon? Using narrative inquiry methodology, this study involved conversational interviews with three participants. Their stories of transition were co-created and analyzed for resonant threads, contextualized within NGN transition theory and existing literature on rural and emergency nursing. Four resonant threads were identified: (a) influential relationships, (b) learning on the job, (c) becoming a rural emergency nurse, and (d) developing confidence. The findings of this study enhance understanding of NGNs’ transition experiences in rural EDs. Readers are encouraged to reflect on these findings in relation to their own practice environments, fostering insight into the unique factors shaping NGN transitions. This understanding can inform the development of tailored, resource-conscious interventions that support NGNs more effectively, ultimately improving retention and ensuring sustainable healthcare delivery in rural settings.
Influence Of Alcohol Washing On The Flavour Profiles And Functionality Of Oilseed Proteins
(2025-03-20) Thommana, Rhea Thomas; Nickerson, Michael T; Reaney, Martin; Ghosh, Supratim; Zhang, Haixia; Chen, Lingyun
Oilseed meals are obtained after pressing and extracting oil from the seed, the remaining meal is predominantly used as animal feed. Oilseed meals are rich in proteins, vitamins, minerals, fibres and have a well-balanced amino acid profile. Due to the increasing demand for protein-rich food, a sustainable and reliable source of protein is essential. Though oilseed meals are an ideal source, the presence of phenols, glucosinolates and phytates impart bitter, off-flavours and dark pigments into the meal. Besides these compounds, oilseed meals also contain antinutritional compounds and have poor functional properties which limit the usage of oilseed meal in the human food industry. The overall goal of this research is to examine the effect of alcohol washing on oilseed meals (canola and sunflower) using two alcohols: ethanol and isopropanol at different concentrations of 35, 65, and 95%. It was hypothesized that this treatment would reduce the off-flavour and dark pigments from the oilseed meals since the flavour and colour-imparting compounds are alcohol-soluble in nature, thus making them acceptable for future use in the food industry. The combined treatment with the change of alcohol concentrations and type increased the protein concentration for both canola and sunflower. For canola, untreated meals had 86% protein, and the highest increase in protein content was observed in 65% ethanol wash (91%). For sunflower, protein content increased the most at 35% isopropanol treatment and increased from 87% to 93%. Lipid content was seen to increase for canola meal at 35% ethanol wash (6%) from untreated canola meal (1%). A similar trend was observed for sunflower protein, where the highest lipid content was observed at 35% ethanol wash (7%) from untreated sunflower protein (1%). At 35% ethanol wash, canola and sunflower meal had considerably lightened for canola and sunflower protein. Functional properties such as water and oil holding properties were improved at 35% ethanol wash (⁓2 g/g) from the untreated canola protein which had around 1.5 g/g water holding capacity and 0.9 g/g oil holding capacity. Water holding capacity was seen to improve the most at 35% isopropanol wash (2.3 g/g) from 1.9 g/g for untreated sunflower protein. Oil holding capacity was seen to improve at 35% ethanol wash (2.0 g/g) from 1% for untreated sunflower protein. Foaming capacity was seen to improve from 140% to 196% at 65% ethanol wash for canola protein and for sunflower protein, the foaming capacity improved from 118% to 147% at 95% ethanol wash. Foaming stability had improved overall after the isopropanol wash in the case of canola protein and for sunflower protein, the foaming stability had not improved significantly. For canola protein, emulsion stability was seen to improve at 65% isopropanol wash from 36% to 47% and for sunflower protein, no improvement was observed after alcohol washing. Protein solubility had significantly increased at 95% isopropanol wash for canola protein. For sunflower protein, the protein solubility had not improved. Aldehydes were the major volatile flavour compounds that were removed after alcohol washing. Around 95% of aldehydes were removed from canola protein. 2- Butenal, 2-Methyl butenal, and 3-Methyl butanal were the aldehyde groups that were predominantly removed from canola protein. The aldehyde compounds such as 2- Butenal contributes a pungent- fruity flavour, 2-Methyl butenal contributes a greenish fruit flavour and 3- Methyl butanal adds a malt flavour to the protein concentrate. For sunflower, hexanal was the aldehyde group predominantly removed after alcohol washing, which contributes towards the grassy flavour of the sunflower protein concentrate. Roughly 90% was removed after ethanol washing and 70% was removed after isopropanol washing. Sinapine is the non-volatile compound that adds bitterness to canola meal protein and chlorogenic acid is the non-volatile compound that adds astringency and bitterness to sunflower protein. The total amount of sinapine was reduced by 20% after 35% ethanol washing which was the highest reduction. In the case of sunflower, the highest amount of chlorogenic acid was reduced by 26% after 65% ethanol washing. Amino acid scores for the oilseed protein concentrate revealed that the only limiting amino acid was lysine. Even though lysine was the limiting amino acid before washing the protein, alcohol washing has improved the amino acid scores for lysine. After calculating IVPD scores, it was seen that there was significant improvement at 35% ethanol (85.9%) wash for canola protein in comparison to untreated canola protein (83.1%). For sunflower protein, there was no negative effect after washing with alcohol. IV-PDCAAS values showed a slightly different trend where the highest value was observed at 95% isopropanol wash (69.2%) from the untreated canola protein (63.8%). While no significant improvement was observed in the IV-PDCAAS values for sunflower protein. Overall ethanol was slightly more effective in comparison to isopropanol treatment. Protein functionalities had improved or had no effect for canola protein, while for sunflower protein, protein functionalities had either improved or had a negative effect (emulsion stability). The flavour compounds were removed effectively after alcohol washing. The overall colour of the sample was also altered based on the alcohol concentrations, it had either lightened or darkened. To attain a clean-tasting product which is widely accepted by consumers and to use oilseed meal as a protein source in the plant-based food industry, the flavour profiles and colour play a crucial role. The data collected from this study will be beneficial to understand the effects of alcohol washing on oilseed meal protein and to thereby increase the utilization of plant-based protein.
Spatial distribution of cougar (Puma Concolor) occurrences in Saskatchewan
(2025-03-20) Windsor, Tammie M; McLoughlin, Phil; Watkins, William; Morrissey, Christy; Brook, Ryan; Perry, Tom
The cougar (Puma concolor) is a rare and elusive predator that was extirpated throughout much of eastern North America by the first half of the 1900s. In Saskatchewan, cougar populations were absent with sightings only incidental until the early 2000s. The recolonization event in the Cypress Upland ecoregion of southwest Saskatchewan (likely from Alberta or Montana) led to an apparent increase in observations throughout the province. Amid public concern over cougar activity in rural and even urban Saskatchewan, understanding the ecology of cougars has become increasingly important. This thesis was directed at developing a thorough understanding of the current state of knowledge for the species in Saskatchewan. Data used herein were from cougar occurrence reports (years ranging from 1942 to 2024) principally obtained from the public through an original survey campaign and records of the Saskatchewan Ministry of Environment. In Chapter 2, I collated data and compared the validity of cougar occurrence reports expert knowledge. For Chapter 3, I formulated an a priori dataset from Chapter 2 results and analyzed these data to model habitat suitability and connectivity for the species. My results further integrate methodologies in obtaining and verifying data gathered from varied (including community-based) sources; and update predicted geographical range and population connectivity maps for cougars in Saskatchewan. In Chapter 4, I reviewed cougar-human conflicts in the literature to suggest conservation and management goals concomitant to achieving human coexistence with cougars. My work has relevance to conserving the species in Saskatchewan by affirming the Saskatchewan Conservation Data Centre’s provincial ranking of cougars through additional data. My maps may also serve to update maps of cougar distribution and abundance, e.g., for the International Union for the Conservation of Nature’s range map for the species.
Impact of fertilizer and cropping management practices on phosphorus recovery in crop and soil, and associated losses in runoff water in variable topographies of Saskatchewan
(2025-03-20) Weiseth, Blake; Schoenau, Jeff; Elliott, Jane; Siciliano, Steven; Helgason, Warren; Bourgault, Maryse; Schneider, Kimberley
Those seeking to effectively manage the fate of phosphorus (P) in the environment must resolve an apparent dichotomy where P may be supplied to growing crops in the form of P fertilizer due to an insufficient supply from soil, but is also a pollutant when surface water bodies receive runoff water enriched in bioavailable P. Across the Canadian Prairie Pothole Region (PPR), P is predominantly transported in the environment in the dissolved form during the spring snowmelt. Losses of P supplied to agricultural fields may be exacerbated when P is applied to seasonally-flooded depressions and lower slopes commonly found in the PPR, especially those which have been drained. However, the degree to which implementation of 4R P Stewardship and other cropping management practices can mitigate P losses in snowmelt runoff water from landscapes of variable topography is largely unknown, and few previous investigations have considered the impact that fertilizer sources of different solubility have on both promoting crop P nutrition and reducing P losses in water. Further, while others have investigated the influence of landscape position and associated slope on nutrient transport in rainfall runoff, its importance in influencing nutrient transport in snowmelt runoff is less well understood. Therefore, this work evaluates agronomic and environmental performance of combinations of 4R fertilizer and cropping management practices across varying landform elements representative of the hummocky terrain of the Canadian PPR. Sites used for the research included upper and lower slope positions of a farm field located in knob and kettle topography in the Brown soil zone near Central Butte, SK, and level slopes and drained basins in gently undulating topography in the Dark Brown soil zone at Discovery Farm near Langham, SK. This work demonstrated that the plant-availability and mobility of P in runoff varied according to the P fertilizer source applied and the chemical properties of the receiving soil. Fertilizer P forms of lower solubility like struvite and rock phosphate sometimes showed lower plant availability of P and yield response, but also resulted in lower losses of P in simulated snowmelt runoff. Notably, soil moisture conditions interacted with the relative solubility of the applied P fertilizer to influence its agronomic and environmental performance. In contrast to its major influence on rainfall runoff losses, slope did not appear to influence soluble P losses in snowmelt runoff, with the muted influence attributed to lower overall energetics of snowmelt relative to rainfall runoff. The performance of fertilizer and cropping management practices implemented to drained agricultural basins was tied to the rate of P fertilizer applied, where variable rate practices that applied reduced rates of P fertilizer in the basins were most effective in lowering soluble P concentrations in snowmelt runoff. However, total P load was driven by the total runoff volume exiting the drained basin during spring snowmelt. Collectively, these findings improve our understanding of the factors that control nutrient transport from agricultural fields in the Canadian PPR and their relative importance. Findings from this work support the site-specific prescription of beneficial management practices intended to maximize crop utilization of applied and residual P, while limiting P losses in snowmelt runoff.
EVALUATING LYGUS FEEDING BEHAVIOR, PREFERENCES, AND PATTERNS IN FABA BEAN CULTIVATION
(2025-03-20) Aguiar Cordero, Maria Teresa; Prager, Sean M; Bett, Kirstin; Willenborg, Christian; Carcamo, Hector; Knodel, Janet
Faba bean (Vicia faba) is a crucial nitrogen-fixing legume crop, particularly important in Western Canada and Saskatchewan due to its adaptability to cool, moist growing conditions and its role in enhancing soil fertility. However, this crop faces significant challenges from insect pests, including Lygus, which feed using piercing-sucking mouthparts that produce mechanical damage to plant tissues. Lygus feeding on faba beans, particularly during the pod stage, results in economic losses through yield reductions, hull perforations, and downgrades in seed quality. Despite their economic impact, the relationship between Lygus feeding behavior and faba bean damage remains insufficiently understood. This study aimed to address key aspects of Lygus biology and ecology on faba beans, focusing on their feeding behavior, host preferences, and spatial distribution. No-choice bioassays quantified the relationship between the number of Lygus individuals, exposure time, and the extent of seed damage. The electrical penetration graph (EPG) technique was employed to analyze the impact of feeding duration on damage in the seed. Choice experiments assessed Lygus host plant preferences, while field surveys across Saskatchewan evaluated Lygus population density, and species composition. Results from these studies revealed significant correlations between Lygus feeding and seed quality, identified plant species preferences, and highlighted variations in population dynamics across different regions. These findings provide critical insights for the development of informed management strategies, contributing to the sustainable cultivation of faba beans and effective pest management practices.
Advancing imaging techniques for assessing inflammation and fibrosis associated with inflammatory bowel disease
(2025-03-19) Goncin, Una; Machtaler, Steven; Machtaler, Steven; Price, Eric; Gould, Layla; Fowler, Sharyle; Farthing, Jon; Brewer, Kimberly
Inflammatory bowel disease (IBD) is a chronic condition that requires accurate early diagnosis and routine monitoring to enable timely treatment and enhance patient outcomes. Current diagnostic techniques are often invasive, costly, unsuitable for routine monitoring, and may not be sensitive to subtle inflammation and fibrosis. This thesis explores three innovative imaging techniques for rapid, noninvasive detection of active inflammation and fibrosis associated with IBD. Positron emission tomography (PET) enables whole-body imaging of molecular and cellular processes in vivo. We developed lipid-shelled “radiodroplets” as a PET agent. Radiodroplets were dual-labeled with a commercial P-selectin antibody and Zirconium-89, demonstrating biodistribution through the reticuloendothelial system with no nonspecific accumulation in the gastrointestinal tract. Preliminary in vivo results demonstrated targeted radiodroplet accumulation within the inflamed bowel of a mouse with acute colitis, highlighting their potential for imaging active inflammation. Ultrasound molecular imaging (USMI) provides a widely accessible and well tolerated alterative for monitoring inflammation at known disease sites. To address the lack of clinically translatable targeted microbubbles for USMI, we systematically optimized the design of selectin-targeted microbubbles. The conventional preclinical streptavidin-biotin coupling method was replaced with strain-promoted alkyne-azide click chemistry. A P-selectin-specific RNA aptamer, modified to reduce nuclease-mediated degradation, was tested as an alternative to commercial non-human antibodies. RNA aptamer-functionalized microbubbles successfully detected active inflammation in two murine models of acute colitis. We then evaluated replacing the RNA aptamer, with a naive DNA aptamer targeting murine and human P-/E-selectin, designed without costly nuclease-resistant modifications. These DNA aptamer-functionalized microbubbles detected inflammation in murine and rabbit colitis models using preclinical and clinical ultrasound systems, showing significant signal enhancement and support for future clinical translation. Quantitative magnetic resonance imaging (MRI) provides valuable insights into macromolecular tissue changes, with the potential to detect fibrosis, a significant complication associated with IBD. We assessed bowel fibrosis in a rat model of chronic IBD using T2 relaxation time estimates. Our findings reveal a strong negative correlation between T2 relaxation time and collagen content in fibrotic rat bowel tissue, supporting its potential use for detecting bowel fibrosis. This thesis advances PET, USMI, and MRI applications for imaging subclinical inflammation and fibrosis, with potential for future integration into the IBD patient imaging framework.
VernierVision: Automatic Reading of Vernier Scales for Historic Observatory Telescopes
(2025-03-18) Wheler, Timothy Jeffrey; Stavness, Ian; Stavness, Ian; Gutwin, Carl; Eramian, Mark
Advancements in deep space optics have revolutionized astronomical research, rendering older observa- tory technologies obsolete. However, these historical resources still hold significant potential to inspire future stargazers. Historic observatories, although outdated for contemporary research, are invaluable for students and amateur astronomers constrained by the cost of modern equipment. This thesis aims to integrate elec- tronic measurement systems into historical telescopes to enable remote and automated use while preserving their original condition. Specifically, the thesis focuses on the Observatory at the University of Saskatchewan, a landmark facility that remains a landmark of substantial significance. Modernizing these telescopes without damaging their irreplaceable components is crucial. Many historical telescopes use manual rotary Vernier scales to measure direction, unlike modern telescopes with rotary encoders. The telescope in this study uses Vernier scales for right ascension and declination measurements. Instead of replacing these scales, this thesis devises and evaluates computer vision approaches to automatically read the original Vernier scales. A computer vision system comprising cameras, object/line detection, and post-processing pipelines was developed to automate scale measurements. The system unifies numeral localization and classification using an object detection network and creates a robust post-processing pipeline for region-of-interest (ROI) and feature extraction. The performance of the final system was sufficient for one of the two scales, however due to additional sources of error, the performance on the second scale was lacking for high precision operation
The Instrumentalization of Drugs in the Hannibal Lecter Tetralogy
(2025-03-17) Yang, Haonan; Banco, Lindsey; Martin, Ann; Liu, Yin
Thomas Harris’s Hannibal Lecter novels create “Hannibal the Cannibal”—an icon in modern pop culture and a controversial character who “transgresses all categories—culture/ nature, crime/ order, human/ animal, rationality/ madness” (Mizejewski 175). In this paper, I will adopt comparative and historicist approaches to explore the representation of drugs in the Hannibal Lecter tetralogy to discern how these texts understand the relationship between good and evil. In the tetralogy, Dr. Lecter instrumentalizes drugs for three purposes—vengeance, playing God, and healing traumas. Lecter’s instrumentalization of drugs not only transforms him into a complicated cannibalistic serial murderer who kills for justice but also transforms Starling into his romantic partner. Drawing on Jacques Derrida’s concept of pharmakon, I will argue that Lecter’s utilization of drugs in his life journey demonstrates the dual nature of his humanity. His instrumentalization of drugs as pharmaka complicates the conventional understanding of drugs in crime fiction primarily as a means of pursuing recreational intoxication and a tool for criminals to achieve evil purposes. Harris’s portrayal of instrumentalizing drugs suggests that psychoactive drugs help to represent the duality of humanity, and, for fictional serial killers, drugs are not a means of self-intoxication but have the multifarious functions of assault, self-protection, and dealing with traumas. By associating cannibalistic serial killing with drug use, Harris critiques the problematic medical system in America, the corruption of the American judicial system, and the theme of excess in American consumption culture.
Deep Learning Methods for Cervical Cell Classification with Cytology Image Data
(2025-03-14) Fang, Ming; Bui, Francis francis.bui@usask.ca; Ko, Seok-Bum; Vizeacoumar, Franco; Wahid, Khan; Maleki, Farhad
Advances in biomedical imaging modalities can provide rich information about the properties of normal and cancerous tissues, assisting medical experts in examining and interpreting the current status of cancers. Biomedical image classification plays an integral role in the diagnosis and treatment of various cancers. Traditional methods have some disadvantages, such as time-consuming and labor-intensive, which significantly affect the effective detection of cancer. In response to these issues, it is necessary to apply computer-aided techniques to automatically analyze medical images, so that patients can be diagnosed and treated timely. With the success of deep learning techniques in the field of computer vision, more and more researchers choose machine and deep learning models as major tools for analyzing biomedical images. Leveraging some machine learning-based algorithms, e.g., classification algorithms, is helpful for medical experts to diagnose disease status since computers may discover the patterns that are difficult for humans to see. Cervical cancer is seriously threatening the lives of women around the world. Fortunately, cervical cancer can be detected and treated as long as it is diagnosed at the early stage. Although traditional methods such as Pap smear test can reduce the death rate of cervical cancer, they are time-consuming and prone to errors. With the emergence of machine and deep learning algorithms, cervical cancer has been diagnosed and treated effectively. However, there are still some challenges in the current detection methods. First, the importance of features of various levels is not fully taken into account in cytology image analysis. Second, the majority of relevant studies only pay attention to the local detailed information while ignoring the global feature information of cells. Moreover, most researchers only focus on the features of images themselves, rather than involving the properties of cervical cells. To improve these issues, I have developed novel and effective computational methods in Chapters 3-5 of this thesis to automatically analyze cervical cell images, further assisting in the diagnosis and treatment of early cervical cancer. Chapter 3 develops a new deep convolutional neural network (CNN) that learns feature patterns by applying multiple kernels with different sizes to automatically classify cervical cells from cytology images. Three different basic modules are designed to capture feature information through multiple kernels with different sizes. Afterwards, several such basic modules are stacked to form the cervical cell classification model. Chapter 4 considers the importance of global features. A deep integrated feature fusion module is proposed to synergize local and global cell features more effectively. Based on a parallel architecture with a CNN branch and a transformer branch, the local and global features are extracted simultaneously, enhancing the discriminative ability of cell features. Chapter 5 incorporates supervised contrastive learning with CNN to construct a novel cervical cell classification framework, to guide the deep model to acquire better cell representations. By generating multiple views of cell images with data augmentation to simulate the pattern variations of cervical cells and jointly training the model with our designed hybrid loss, the proposed framework improves the robustness in cervical cell representations and addresses challenges, including the pattern variations in cervical cells caused by the data acquisition process and the misclassification of cells with similar pathological properties. In summary, this thesis begins with relevant background knowledge that describes the proposed research objectives and pipelines. Subsequently, the thesis presents a comprehensive review of the existing literature on deep learning-based cervical cell image analysis, identifying key findings and challenges in the current research, as well as providing a foundation for the subsequent analysis. Next, this thesis develops several new methodologies for automatic detection of cervical cell abnormalities. A substantial number of comparative experiments demonstrate the effectiveness of the developed methods, which could be viewed as an auxiliary tool to support clinical use for cervical cancer.
Geochemical Evolution of Froth Treatment Tailings at and Oil Sands Mine in Northern Alberta, Canada
(2025-03-14) Paulsen, Joshua J; Lindsay, Matthew B.J.; Ferguson, Grant; Smith, Laura A; Sproat, Colin D
Froth Treatment Tailings (FTT) are generated during water-based bitumen extraction in the oil sands mining operations in Northern Alberta, Canada. Acid generation and metal(loid) release during sulfide-mineral oxidation is an emerging consideration for management and reclamation of FTT deposits. This pyrite-bearing tailings stream is deposited sub-aerially where post-depositional hydraulic segregation of FTT slurry generates beach deposits susceptible to oxidative weathering. Recent studies have demonstrated the potential for acid generation and metal(loid) release during oxidative weathering of FTT however, the geochemical evolution of commercial scale FTT beach deposits is not fully understood. Refining the geochemical conceptual model of FTT beach deposits will provide insight into tailings management strategies and landform reclamation planning. This research examines the geochemical evolution of a commercial-scale sub-aerial FTT beach deposit. A sampling campaign was completed on the Plant 6 FTT beach deposit at the Mildred Lake mine operated by Syncrude Canada Ltd (Syncrude). Continuous core sampling was conducted on five boreholes collected along a transect of the P6 FTT Beach deposit which approximately followed historic FTT deposition points. Boreholes were drilled to a depth ranging from approximately 30 to 46 m and tailings solid samples were collected along the borehole depth profiles at each location. Tailings pore-water was extracted by mechanical squeezing from solid samples and tailings solids were sub-sampled for subsequent analysis. Mineralogical analysis revealed that FTT beach solids are generally dominated by quartz plus various phyllosilicates, sulfides, carbonates, oxides, phosphates, and additional silicates occurring at minor to trace amounts. Sulfide and carbonate mineral contents each range from approximately 5 to 10 wt. % but their abundance can exceed 20 wt. % at discrete locations. Pyrite and minor marcasite are the only sulfides detected in FTT beach samples. Siderite is the dominant carbonate in both weathered and non-weathered FTT beach samples, which commonly contain lesser amounts of dolomite, ankerite, and calcite. Pore-waters in non-weathered regions of the FTT beach deposit are generally characterized by circum-neutral pH (7–8) and relatively low dissolved SO4, Fe, and metal(loid) concentrations.
Vegetable and fruit intake and diet quality changes in women who participate in prenatal programming involving a dietitian: A scoping review.
(2025-03-14) Boyer, Audrey; Lieffers, Jessica; Cammer, Allison; Jorgensen, Derek; Vatanparast, Hassan
The abstract of this item is unavailable due to an embargo.
Housing Rights Implications of Hosting the 2026 FIFA World Cup in Toronto and Vancouver: Towards a Legal Framework that Effectively Protects the Right to Adequate Housing in Canada
(2025-03-10) Aneke, Kenechukwu Christopher; Newman, Dwight Gordon; Buhler, Sarah Marie; von Tigerstrom, Barbara Joanne; Dennie, Martine
Féderation Internationale de Football Association (FIFA) organizes the greatest sporting event in the history of soccer – the FIFA World Cup (FWC). The 2026 FWC starts in June 2026, with Canada, Mexico, and the US as host nations. This thesis focuses on Canada to ascertain how the hosting of the 2026 FWC could impact the right to adequate housing in the host provinces/cities of Ontario/Toronto and British Columbia/Vancouver vis-à-vis the already precarious housing situation in these provinces/cities and the anticipated high demand that would be placed on the housing market by soccer fans and spectators coming into the host cities in 2026. The thesis thus analyzes the central issue of whether or not the hosting of the 2026 FWC in Toronto and Vancouver obliges the Government of Canada and the provincial/municipal governments of these host provinces/cities to initiate immediate appropriate legislative measures that address the possible impacts the 2026 FWC could have on right to adequate housing. To ascertain this, the thesis first provides the much needed background to the possible housing rights risks of the 2026 FWC. Given the dearth of scholarly works on the housing rights implications of past FWCs, the thesis evaluated the housing rights impacts of five different Olympic events as a precursor that highlights the possible adverse impacts on housing rights that should be of concern to the host cities of Toronto and Vancouver. The thesis further examines and discusses the immediate obligations of the government in Canada under the International Covenant on Economic, Social and Cultural Rights and under FIFA’s human rights initiatives, to - through appropriate legislative measures - protect against the housing rights risks of the 2026 FWC. The thesis also analyzes the efficacy of the housing rights frameworks in the host provinces/cities, and concludes with proposals and recommendations that would facilitate a hosting experience in Toronto and Vancouver that does not violate housing rights.
Biochar Based Composite Material: Study of Mechanical and Physicochemical Properties
(2025-03-10) Masoudi, Mehdi; Zhang, Lifeng Dr; Acharya, Bishnu Dr; Panigrahi, Satya Dr
This research explores the development of sustainable polymer composites by using carbon-based materials to reinforce them and assess their mechanical and thermal properties. With the growing need for eco-friendly materials, biochar a renewable material derived from agricultural or organic waste emerges as a promising candidate to enhance polymer composites' performance, providing a sustainable alternative to traditional materials. In this study, polymer composites were created by incorporating various amounts of carbon-based reinforcements. The main polymers investigated were polylactic acid (PLA), low-density polyethylene (LDPE), and linear low-density polyethylene (LLDPE). To determine the effects of biochar, mechanical properties such as TS, YM, and EB were measured. Additionally, changes in the composites' density with increasing biochar content were evaluated. A comparative analysis was also conducted with carbon black, a known filler, to see how different carbon-based materials perform. Results showed that increasing biochar content led to higher composite density, attributed to the greater mass and packing density of biochar particles within the polymer matrix. However, the mechanical properties did not follow a consistent pattern of improvement with higher biochar content. Instead, the impact on these properties varied depending on the polymer matrix and the amount of biochar used. Although biochar increased the material’s density effectively, its influence on mechanical behavior was complex and multifaceted. The inclusion of carbon reinforcement typically reduced the composites' plastic properties but adding 10% polyethylene glycol (PEG) helped restore these properties closer to those of the original polymer. Thermal properties were examined using Differential Scanning Calorimetry (DSC). The analysis revealed that the heat flow and melting points of biocomposites increased with higher biochar content. For PLA-based composites, the melting point increased by 11°C with 40% biochar, while for LDPE and LLDPE, the melting point rose by 25°C with the same reinforcement percentage. These findings indicate that biochar enhances the density and thermal stability of polymer composites, while its impact on mechanical properties remains III variable. The decrease in Melt Flow Index (MFI) was linked to the composites' elevated melting points, affecting their flow properties during processing. Moisture absorption tests demonstrated that composites with carbon reinforcement had notable water uptake due to pore formation and increased surface area, with LDPE and LLDPE composites showing about 0.6% absorption, while PLA composites reached 1.6%. This research supports the ongoing efforts to develop more sustainable composite materials, with potential applications across various industrial sectors.
IMPACTS OF ENZYMES, TANNASE, DIOXYGENASE, AND THEIR BIOENGINEERED MUTANTS, ON TOTAL PHENOLIC REDUCTION IN PURIFIED TANNIC ACID AND PLANT EXTRACTS AND EFFECTS OF TANNINS ON SODIUM-GLUCOSE CO-TRANSPORTERS (SGLTs) IN RAINBOW TROUT (Oncorhynchus mykiss)
(2025-03-10) CHERIAN, Rinta; Loewen, Matthew E; Beaulieu, Denise; Penner, Gregory; MacPhee, Daniel
The abstract of this item is unavailable due to an embargo.
Determination of Water Vapor Sorption Isotherms of Cannabis Inflorescence
(2025-03-10) Vista, Alec Roger Jalbuna; Tabil, Lope; Baik, Oon-Doo; Guo, Huiqing; Veikle, Spencer; Cree, Duncan
The abstract of this item is unavailable due to an embargo.
Acute intermittent hypoxia (AIH) as a non-invasive therapy for the treatment of multiple sclerosis (MS)
(2025-03-10) Tokarska, Nataliya; Verge, Valerie M.K; Donkers, Sarah J; Knox, Katherine B; Levin, Michael C; Krishnan, Anand; Popescu, Bogdan F; Campanucci, Veronica A; Karimi-Abdolrezaee, Soheila
The abstract of this item is unavailable due to an embargo.
Genetic Diversity Among Ferruginous and Swainson's Hawks: An Interdisciplinary Interpretation
(1997) Portman, Janita S.; Schmutz, Joe; Plante, Yves; Bortolotti, Gary
Ferruginous hawk (Buteo regalis) populations and breeding range have declined since prairie settlement. Concern over this downward trend led the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) to list ferruginous hawks as "threatened" in 1980. Current populations appear to have stabilized within the reduced range and ferruginous hawks were downlisted to "vulnerable" in 1995. While stable populations are positive for hawk conservation, genetic diversity may have been negatively impacted by hawk population declines and changes in distribution. Loss of genetic diversity may reduce a population's chances of long-term survival by increasing frequencies of harmful alleles or by reducing the genetic capacity of a population to adapt to environmental changes. I assessed genetic diversity among ferruginous hawks from seven sites in prairie Canada and Idaho, U. S. A. using DNA fingerprinting. I also analyzed DNA from Swainson's hawks (Buteo swainsoni), a widespread and more numerous prairie hawk. Unlike ferruginous hawks, Swainson's hawks did not undergo large population or range reductions during settlement. Therefore they serve as a useful species with which to compare ferruginous hawks. High Average Percent Differences (APD's) in band sharing and heterozygosity estimates from DNA fingerprints indicate a high genetic diversity among sampled populations of both ferruginous and Swainson's hawks. Ferruginous hawk APD and heterozygosity estimates were similar to both Swainson's hawk estimates and those reported for other bird species with large stable populations. I also assessed population subdivision (Dij) to determine whether hawks interbred among the sample sites. I found slight population subdivision between Hanna and Southwest Alberta ferruginous hawks (Dij = 0.06 ± 0.04, Median test, p<0.025). The most likely explanation for this observation is a local extirpation event (possibly in SW Alberta) followed by recolonization with a small number of hawks. Some level of subdivision could be established through inbreeding and maintained through philopatry. This subdivision is slight compared to published reports in which APD's are noticeably higher between subdivided populations. I detected no population subdivision among all other ferruginous and Swainson's hawk sites suggesting that interbreeding, through natal and/or breeding dispersal, is occurring throughout the range. Current genetic diversity is unlikely to limit long-term persistence of ferruginous hawk populations. The future range and population size are likely determined by human social and economic decisions that affect land use patterns on the prairies.

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