University of Saskatchewan Research Archive
Not a member yet
14369 research outputs found
Sort by
Regulating the use of Crypto-assets as collateral in secured transactions: U.S and Canadian Perspectives
Get PDFThe thesis is focused on regulating the use of crypto-assets as collateral in secured transactions. The ability of a debtor to receive a loan from a lender in exchange for its collateral is a vital part of global commercial activity. Crypto-assets are a relatively new asset class introduced with the term “cryptocurrency” in the Bitcoin Whitepaper released by Satoshi Nakamoto in 2008. Since the invention of crypto-assets, many regulatory efforts have been made to govern the use of crypto-assets by different countries including Canada. These regulatory efforts have led to policies on crypto-assets in several contexts such as taxation and their use in financial crimes. That crypto-assets use in secured transactions has yet to be expressly regulated in Canada has led to speculation on how the current personal property security law in Canada applies to crypto-assets. An examination of the current personal property security law in Canada reveals that, under existing law, it is difficult to acquire a reliable and effective security interest in crypto-assets. This thesis, therefore, identifies the current issues hampering the appropriate regulation of crypto-assets under Canadian secured transaction law, evaluates the consistency of the relevant laws with guiding secured transaction values such as facility and certainty, and recommends possible solutions to the current issues. The issues include the failure to expressly categorize crypto-assets as a form of personal property, the lack of suitable modes of perfecting security interests in crypto-assets, and the non-negotiability of crypto-assets. The analysis and recommendations made in this thesis are intended to bring the issues with crypto-related secured transactions to light so that they may be considered and addressed by lawmakers in Canada. The recommendations in this thesis will also be of interest to jurisdictions with similar secured transaction regulatory frameworks, which are considering the incorporation of crypto-assets into their secured transactions legislation as a unique form of personal property
Development of novel Competitive Enzyme-linked immunosorbent assays to detect SARS-CoV-2-specific antibodies in animals
Get PDFSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the COVID-19-causing virus, is a zoonotic pathogen. There is concern about the virus spilling over from humans into wildlife species, which may then serve as reservoirs for future infection of humans and other animals. Furthermore, the level of exposure of potentially susceptible wildlife species is currently not known. There is, therefore, an urgent need to develop a single test that could be used for the serosurveillance of multiple wildlife species for exposure to SARS-CoV-2. Although there are serological techniques to detect the exposure of humans to the virus, few assays have the capacity to detect antibodies in a wide variety of species. Here, I describe the development of a competitive enzyme-linked immunosorbent assay (cELISA) to detect SARS-CoV-2 antibodies in mammals for which species-specific reagents are not available. Therefore, cELISAs were developed to detect SARS-CoV-2 spike S1 and S2 domains and nucleocapsid (N) specific antibodies and were validated using sera from experimentally infected hamsters. We further validated our cELISA by comparing it with results obtained from the surrogate virus neutralization test (cPASS, GenScript) and indirect ELISA using anti-hamster horse radish peroxidase (HRP) conjugated reagents. Our initial cELISA was based on the ability of test antibodies to displace the binding of commercially obtained rabbit antibodies against viral proteins coated on the ELISA plate. Rabbit antibody reagents are expensive and anti-rabbit detection antibody may cross-react with other mammalian antibodies. Therefore, I explored the use of antibodies produced in hen eggs (IgY) as a substitute for rabbit sera. Hens were immunized against SARS-CoV-2 antigens: S1, S2 and N. IgY antibodies were purified from egg yolk, and the assay was optimized to use specific antibody and antigen combinations. Among S1, S2 and N-IgYs, only the S2-IgY based cELISA was specific and comparable with both the rabbit anti serum based cELISA and the surrogate virus neutralization test (cPASS). This assay will be a valuable tool which can be implemented in surveillance programs investigating exposure to and transmission of SARS-CoV-2 in multiple domestic, captive, or wildlife species
Quantifying the Diversity of Agronomic Traits of Cicer Milkvetch (Astragalus cicer L.) Germplasm Collections Using UAV-Based Imagery
No full textThe abstract of this item is unavailable due to an embargo
Nestling Diet, Quality, and Post-fledging Survival: Comparing Two Species of Aerial Insectivores in a Gradient of Agricultural Intensity in Saskatchewan, Canada
Get PDFIn the last decades, several species of avian aerial insectivores have experienced steep declines in different regions of North America, and no single driver has been identified. Given the common reliance of aerial insectivores on flying insects, changes in spatiotemporal availability of prey abundance and quality caused by agricultural intensification have been implicated in their decline. The quality of nestling nutrition mediated by parental selection of insect prey types (aquatic versus terrestrial) can be an important determinant of offspring health and development which, in turn, can have lasting effects on future life-stages, including the post-fledging transitional period to independence.
In 2020 and 2021, using a comparative approach between two sympatric species, Barn Swallows (Hirundo rustica) and Tree Swallows (Tachycineta bicolor), following a scale-of-effect approach, I investigated whether the intensity of agriculture was associated with parental selection of prey resources, nestling body condition and growth. Stable isotope data revealed Barn Swallows opportunistically used aquatic aerial prey resources to provision nestlings when available, whereas Tree Swallows strongly relied on aquatic-emergent prey, regardless of the availability of wetlands in the immediate area around the nest ( 5 km).
This work adds to the growing evidence that conservation of wetlands and naturalized areas within the agricultural landscape in the Prairie Pothole Region is important for breeding aerial insectivores, including Tree and Barn Swallows, and may be helping mitigate the negative effects of intensive agricultural crop production. This study also contributes to filling gaps in our understanding of swallow ecology during the post-fledging period, a poorly understood stage of their life cycle and an important demographic driver of annual population growth in songbirds
UNDERSTANDING THE ROLE OF LEADERSHIP PRACTICE IN THE IMPLEMENTATION OF EDUCATION FOR SUSTAINABLE DEVELOPMENT
Get PDFThe purpose of this qualitative study was to explore the role of leadership practice in the implementation of Education for Sustainable Development (ESD). To do this, the study which was conducted in one elementary school in Western Canada utilized a theoretical framework that views leadership as a collaborative process linked with practice rather than a trait, behavior, or competencies that can be evaluated or rated. As a result, the leadership-as-practice (LAP) theory, which presents leadership as a social and material process served as the theoretical framework for this study.
The study was conducted using a case study approach that was informed by a pragmatic orientation. The study’s participants, who included parents, teachers, and students associated with the ESD program in Western Canada, were chosen using purposive sampling. Relevant research data were collected through observations, semi-structured interviews, and document analysis. Insights and greater understanding of the concept and role of leadership in the implementation of ESD were produced through manual data analysis.
This study was premised on the growing need to question the presumptions that traditional leadership theories are built upon. Findings from the study revealed the possibility that collective leadership may be a wise and effective form of leadership for implementing ESD in schools. The study’s findings also demonstrate that in order to achieve sustainable development, it is necessary for multiple agents to collaborate and use their creativity to enact ESD. As a result, if we are to acknowledge the value of collective leadership in schools, its development would require a different learning approach that empowers students to lead for sustainability. Conclusively, the study’s findings show that leadership for ESD requires a deep absorption into the practices that are ingrained in sociomaterial relations
Graduate Student Experiences of Indigenous Studies in Post-Secondary Education: A Comparative Study of Norway and Canada
Get PDFIndigenous Studies is a newer discipline in post-secondary institutions. In the current literature, much focus has been given to the emergence of the discipline, key qualities and concepts significant in shaping the discipline, and the goals and future of Indigenous Studies. However, at the time of this study, no attention has been given to the experiences of students within the discipline. This study intends to help fill the gap in the literature by exploring what the expectations and experiences of Indigenous Studies alumni in Norway and Canada are, and what this tells us about Indigenous Studies programs in these countries. Through semi-structured interviews and conversational method alumni from four different yet comparable Indigenous Studies programs in Norway and Canada have shared their experiences in their master’s programs. By analyzing these experiences through an anti-colonial framework this study demonstrates that there are inconsistencies in the quality, depth, and breadth of Indigenous Studies master’s programs in Norway and Canada, and a gap between student expectations and their actual experiences
Endocannabinoid and Orexin Interactions, With a Special Consideration for Sex- and Estrous Cycle-Dependent Differences
No full textThe abstract of this item is unavailable due to an embargo
Yukon River Basin Streamflow Forecasting System - Advancing, Calibrating, Demonstrating Snow Assimilation and Estimating Ungauged Basin Flow: The Vector-Based MESH Model of the Yukon River Basin
No full textYukon Environment, Global Water Futures ProgramThe Yukon River Basin the second largest river in the Arctic region of North America and is shared between Canada and the US. The Canadian part covers almost half of the Yukon Territory in addition to a small portion of the province of British Columbia, while the US part falls totally within the state of Alaska. This study is concerned with Canadian part of the Yukon River with its outlet at Eagle, Alaska - just downstream of the international boundary (288,000 km2). The southern part of the Yukon River basin is characterized by extensive icefields and snowfields at high elevations (up to 4700 m above sea level) with steep slopes, and thus generates considerable runoff. There are also mountain ranges on the eastern and northern boundaries of the basin, while the western areas are milder in slope and partially forested. Snow redistribution by wind, snowmelt, glacier melt and frozen soil processes in winter and spring along with summertime rainfall-runoff and evapotranspiration processes are thus key to the simulation of streamflow in the basin.
This supplement shows further development of a vector-based MESH setup for the Canadian portion of the Yukon River Basin down to Eagle, Alaska. For operational forecasting, MESH is driven by the Environment and Climate Change Canada Global Multiscale Model (GEM) weather model forecasts with precipitation replaced with the Canadian Precipitation Analysis (CaPA) which assimilates local precipitation observations where they exist, collectively referred to as GEM-CaPA. Additionally, the newly developed Regional Deterministic Reforecast System v2.1 (RDRS v2.1) forcing has been extended to span the period 1980-2018 enabling long-term assessments of hydrology. The revised vector-based model was calibrated for operational use based on the GEM-CaPA forcing dataset, and for performing historical simulations based on the RDRS v2.1 forcing dataset, using the period 2004-2011 in both cases. Performance was compared to the previously generated grid-based MESH model whose development was documented in Centre for Hydrology Report #16. A long-term historical simulation was then performed using RDRS v2.1 from which streamflow exceedance return periods for 15 important stations were calculated and presented in this supplement. Calibration has generally improved the performance of the vector-based setup compared to the previous simulations presented in supplement #1 of report #16. Parameter sets are slightly different when the model is calibrated to RDRS v2.1 compared to GEM-CaPA due to differences between the two datasets.
A pilot study of the potential benefits of snow data assimilation into the existing MESH forecast system was conducted using historical data and the gridded MESH product that is used operationally by Yukon Environment. This test showed benefits to assimilating surface snowpack observations into MESH to correct winter precipitation. Outputs with assimilation showed improved snowpack simulations and improved streamflow forecasts
Improving green supply chain performance with Operations Research
Get PDFDue to increasing greenhouse gas emission as a consequence of the production activities in various industries, managing the supply chain has been a big concern between both scholars and practitioners. Green supplier selection and order allocation is among important topics that managers should pay attention to as the majority of the supply chain costs and emission level during production process depends on the procured material by suppliers. Also, investigating the emission abatement regulations, and interactions between regulator and manufacturers is one of the main concerns of supply chain managers that should be figured out.
In the present study, green supply chain problems are taken into account for more investigations. First, a green supplier selection and order allocation model in a closed-loop supply chain considering both environmental and economical criteria, is studied. In this study, one of the carbon emission abatement schemes, cap-and-trade mechanism is proposed. The described problem is modeled as a multi-objective robust optimization (RO) model. Second, the cap-and-trade (C\&T) mechanism is further investigated. The goal of this investigation is to find the best strategy for supply chain parties to maximize their utility as well as minimize the carbon emission. To model the described problem, a stochastic three-player game theoretical model is developed.
The results show that the developed models can effectively help decision makers select the most appropriate suppliers, allocate the proper amount of order to each selected supplier, and find optimal strategy of C\&T players. Also, the results show that the uncertainty control approaches used in the presented models are capable of handling the model uncertainties from different sources. Furthermore, this study shows that C\&T outperforms the penalty based systems in terms of the total utility of the supply chain. Moreover, the robustness of the results is proved by sensitivity analyses.
Another area that is investigated in this study is the disruption effects on supply chain. Disasters and pandemics like COVID-19 can destroy industries by causing huge disruptions in their supply chains. To control these disruptions, decision-makers need to design resilient supply chains. This study proposes a multi-stage, multi-period resilient green supply chain design model considering six resilient strategies. Disruptions are taken into account in both downstream and upstream directions, causing the ripple effect and bullwhip effect, respectively. To control the mentioned disruptions, and handle uncertainties of parameter estimations, a two-stage stochastic optimization approach is applied. The objectives are to minimize the total cost of disruption and emission considering the cap-and-trade mechanism as a government-issued emission regulation. The proposed decision-making framework and solution approach are validated using a numerical experiment followed by a sensitivity analysis. The results show the optimal structure of the supply chain and the best resilient strategies to mitigate the ripple effect. Moreover, the effect of a decrease in capacity of facilities on the optimal solution and the applied resilient strategies is investigated. This study provides managerial insights to help governments set the proper amount of cap and supply chain managers to predict the demand behaviour of essential and non-essential products in the event of disruptions
Individual and Combined Effects of Selected Emerging Safeners: Mefenpyr di-ethyl and Cyprosulfamide and their Co-Herbicides, Fenoxaprop-P-ethyl and Isoxaflutole on Daphnia magna and Danio rerio
Get PDFAbstract
Herbicides and safeners have been formulated together to help protect crop plants from the injurious effects of herbicides while maintaining the ability of the herbicides to selectively remove targeted weeds. These groups of compounds became important as agriculture increased to sustain the world's ever-increasing population. Selected emerging safeners (SESs), Mefenpyr di-ethyl (MEF) and Cyprosulfamide (CPS) and their co-herbicides (Fenoxaprop-p-ethyl (FEN) and Isoxaflutole (ISO)) used during pre- and post-emergence of cereals and grains were used for this study. The mobility of safeners varied in the environment in relation to their chemical properties, such as octanol-water solubility partition coefficient. Herbicides and safeners have been found in the aquatic environment because they could dissipate from the point of application through leaching, surface runoff, and volatilization. The sorption of safeners such as CPS to soil was found to be governed by soil pH. Hence, their ability to leach varies for soils depending on their acidity/alkalinity. Safeners are classified as inert for regulatory purposes because they mostly act by upregulating detoxifying enzymes. Despite their presence in surface water and their mobility, there is limited or no data regarding their toxicity to non-target organisms in aquatic environments. Thus, the study focused on evaluating and assessing the toxicity of the SESs on non-target organisms such as Daphnia magna-a cladoceran invertebrate, and Zebrafish (D. rerio)- an aquatic vertebrate animal model.
Specifically, the primary objectives of this study were to 1) evaluate and further expand our knowledge on the toxicity of selected safeners for which little toxicological knowledge regarding non-target species like daphnids and fish exist; 2) to evaluate these chemicals singly and in a mixture in an in vivo approach that helps to assess acute, sublethal and chronic effects on the selected model aquatic animals; 3) use simulation models of molecular docking to understand further the interaction of SESs and their herbicides with respect to their binding affinity and predict toxicity on receptors such as growth receptor (4XNN)and hatching enzymes (ZHE1). To address the information gap regarding toxicity of selected safeners, in vivo studies and biochemical assays were done to understand possible reactions in the system of the animals after exposure to serial concentrations of SESs in acute and chronic water-borne exposures. Results from the study showed sublethal and lethal effects on both organisms exposed to MEF and FEN singly and mixed at environmentally relevant concentrations. Lower concentrations of these chemicals caused deformities and inhibited hatching rate, while such effects were not observed for CPS and ISO at the same concentrations. MEF was classified as moderate to high-risk level according to ADMET software. On the contrary, CPS had low to moderate risk levels for both D. magna and D. rerio. A biphasic plot indicating a hormetic reaction was obtained for reproduction in D. magna, suggesting that MEF might be an endocrine-disrupting chemical and induce stress. Lower concentrations (< 3 mg/L) of MEF caused deformations and inhibited the hatching rate in D. rerio embryos. Mixture studies showed infra-additive reactions on endpoints, including survival and hatching rate. Biochemical activities showed a downregulation in GST in some of the chemicals and an inhibition in SOD activities, the organism is mounting an antioxidant response to maintain homeostasis. Molecular docking scores suggested that MEF, CPS, ISO and FEN all binds to the studied receptors (growth (4XNN) and hatching (ZHE1)). Therefore, MEF and CPS have potentials to affect the activities of the selected receptors. Likewise, toxicity estimation software (TEST) predicted MEF and FEN to be developmental toxicants, and that FEN was predicted to have mutagenic potential using consensus method to calculate the end point. While MEF was more potent singly, its toxicity was reduced when in a mixture with another toxic compound (FEN), and this is beneficial to the organism. In the same vein, CPS, which has low potency, also suppressed the toxicity of ISO. The key findings from this study were that even if SESs contributed to mitigating the effects of herbicides on the animal models, there are sublethal effects associated with it, and the adverse outcome is still a cause for concern. Also, safeners categorized as inert should be re-evaluated to account for all their toxic potential.