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The dominant discourse in Indigenous consultations: when rules impede engagement
Get PDFIn Canada, consulting with Indigenous communities over recourse projects, the Crown
sometimes avoids critical engagement with them, holding to the same arguments
and counterarguments through regulatory and hearing stages. Such hollow moves,
produced under the Crown’s rules, become embedded in the dominant argumentative
discourse and pass unnoticed. To detect them, I apply Argument Continuities (AC) – a
new category of argumentative discourse analysis. ACs are a set of the same arguments
and counterarguments repeatedly produced/reproduced by the dominant arguer
through an adversarial reasoning process to dismiss opposing arguments. ACs have
a specific life cycle – a chain of reasoning dynamics developing in a path-dependent
fashion and increasing the cost of adopting a certain argument/counterargument
over time. I test ACs in two institutionally diverse cases of Indigenous consultations
and argue for the contingency of ACs upon the rules of consultations in reasoning
exchanges. Determining the evidence availability and allocating the burdens of proof
in consultations, rules make it more or less likely for a dominant arguer to rebut
opposing arguments with ACs
Integrated Crop-Livestock Systems and the Prairie Landscape: A Feasibility Assessment
Get PDFSustainability is a broad term and consequently, there is no concrete definition of what constitutes a sustainable farm. Inherently there is no correct way to improve on-farm sustainability, and it is recommended that farms find their best production fit by assessing a variety of possible methods for their established operation (Sustainable Agriculture Initiative Platform 2015). Integrated crop-livestock systems (ICLS) are opportunities that take ecological advantage of both cattle grazing and cover cropping, but the strength of that option in Canadian prairie conditions is relatively uncertain. The combination of missing research, economic valuations, and innovative supports have potentially established barriers preventing mainstream adoption of ICLS. If ICLS is to be a viable option for Canadian producers, then the system must be evaluated with the rigid and exogenous facets of the agricultural environment in mind.
The analyses made in this thesis are from 503 farmers who responded to an April 2022 survey that assessed opinions surrounding integrated crop-livestock systems and their motivations for use. Due to resource-sharing convenience, ICLS is largely approached by mixed farms (Thiessen Martens et al. 2015), unintentionally moving the system toward a ‘niche’ standing exclusionary of single-output enterprises. In response to this trend, the survey frames ICLS as a partnership between a neighbouring crop producer and cattle rancher, and question sets partially differ based on (self-identified) farm type. Field data collected from 2019-2021 at the Swift Current Research and Development Centre provides the economic context (performance indicators) for grazing cover crops in the discrete choice experiment (DCE).
Results suggest that there is an interest in integrated systems, but not necessarily in an ICLS partnership. Approximately 75 per cent of participants place trust in their neighbours for novel information and 30 per cent of respondents declared they would not work with someone they do not know, despite assurances. Partnership aside, crop farmers appear to have more ICLS apprehension than cattle producers, suggesting the necessity of stronger information networks for (performance) reassurance. This thesis suggests the social structure of Canadian agriculture is designed to prioritize independence rather than collaboration, which may be just as strong a barrier to integrated adoption as the enviro-economic trade-offs
Soil denitrification response to increased urea concentration constrains nitrous oxide emissions in a simulated cattle urine patch
No full textThis version of the article has been accepted for publication, after peer review (when applicable) and is subject to Springer Nature’s AM terms of use, but is not the Version of Record and does not reflect post-acceptance improvements, or any corrections. The Version of Record is available online at: https://doi.org/10.1007/s11104-023-06048-wCanadian Agricultural Partnership through the Agriculture Greenhouse Gases Program (AGGP II, grant number AGGP 2–011) and Natural Sciences and Engineering Research Council Discovery Grants to MMA (RGPIN-2016–04968) and BLH (RGPIN-2019–04158).Peer ReviewedAim
Incorporating non-bloat legumes into grass pastures can reduce enteric methane and alter cattle urinary urea N output by increasing protein intake. Deposition of high urea N urine influences soil N-cycling microbes and potentially N2O production. We studied how urine urea N concentration affects soil nitrifier and denitrifier abundances, activities, and N2O production.
Methods
15N13C-labelled urea dissolved in cattle urine was added at 3.5 and 7.0 g L−1 to soils from a grazed, non-bloat legume pasture and incubated under controlled conditions. CO2, N2O, 13C-CO2, and 15N-N2O production were quantified over 240 h, along with nitrifier and denitrifier N-cycling genes and mRNA transcripts.
Results
High urea urine increased total N2O relative to the control; low urea was not significantly different from the control or the high urea treatment. As a result, N2O-N emission factors were not significantly different between the low urea treatment (1.17%) and high urea treatment (0.94%). Doubling urea concentration doubled CO2-Curea and N2O-Nurea but not total N2O-N. Urine addition initially inhibited then increased AOB transcripts and gene abundances. nirK and nirS transcript abundances indicated that denitrification by ammonia oxidizers and/or heterotrophic denitrifiers dominated N2O production. Urine addition increased nosZ-II vs. nosZ-I transcripts, improving soil N2O reduction potential.
Conclusion
Characterizing this interplay between nitrifiers and denitrifiers improves the understanding of urine patch N2O sinks and source dynamics. This mechanistic information helps to explain the constrained short-term N2O emissions observed in response to excess urine N excretion from cattle consuming high protein diets, e.g. non-bloat legumes
Global Optimization of Resonant X-ray Reflectometry Models: Analysis of Perovskite Oxide Heterostructures
No full textResonant x-ray reflectometry is an emerging synchrotron technique used to characterize the depth-dependent structure of quantum materials. The main challenge impeding the success of resonant x-ray
reflectometry is the extreme difficulty of analyzing the data because the process involves both large-scale
computational quantum mechanics simulations and the fitting of many independent variables. This leads
to prolonged analysis periods that require a significant amount of engagement. As a part of this thesis, a
new data analysis software named Global Optimization of Resonant X-ray Reflectometry was developed for
researchers to use to more effectively analyze resonant x-ray reflectometry data and to mitigate some of these
challenges. It has been shown throughout this thesis that multiple features in the software have been able
to ease the data analysis process. A large focus will be put on the customizable objective function because
the boundaries and weights and total variation features have been proven to be integral components to the
success of the software.
The developed software was used to analyze resonant x-ray reflectometry (RXR) data of the catalyst
La0.7Sr0.3MnO3/SrTiO3 (LSMO/STO) for electrochemical water splitting. Resonant x-ray reflectometry is
used to develop a new enhanced understanding of the structural, electronic, and magnetic depth profiles of
thin LSMO films by characterizing the depth-dependence of such materials for varying film thickness and
measurement temperature. The results provide evidence of a magnetically dead layer at the surface and
demonstrate a decrease in the magnetic moment near the Curie temperature. These findings are significant
because they help understand the mechanisms involved in the oxygen evolution reaction and methods that
can be used to improve water splitting efficiency.
Resonant x-ray reflectometry is also employed to study the thickness relationship between film thickness
and the presence of ferromagnetism in the LaMnO3/SrTiO3 heterostructure. The electronic reconstruction
due to polar catastrophe is the leading theory for the mechanism involved in the magnetic phase transition,
but this study provides a new understanding of the emergence of magnetism in ultra-thin films of LaMnO3
that contradict the polar catastrophe mechanism. Notably, ferromagnetism is detected below the critical
thickness, as supported by density functional theory calculations. Moreover, this study provides evidence
that the magnetic moment is related to the distortions in the material. It is possible that octahedral distortions are formed and are the proposed cause for the observed ferromagnetism
How Have Increased Grocery Prices Affected Food Purchasing Behaviours?
No full textA study conducted by NUTR 230 students from the University of Saskatchewan on the impacts of increased grocery prices and its effects on student's and faculty/staff's food purchasing behaviours. The data includes whether participants notice an increase in grocery prices, how food purchasing behaviours have changed, and if they believe their diet’s nutritional value has suffered due to inflation.Non-Peer Reviewe
COMPARATIVE PROTEOMIC STUDIES OF SPROUTED LENTIL
Get PDFA major portion of lentil nutritional composition consists of protein and protein-derived biomolecules. Seed germination improves the protein quality. It is important to identify at what stage of seed germination the type and quality of protein improvement occurs. This study aimed to elucidate the molecular mechanism of seed germination in terms of proteomic changes that occur during distinct stages of seed germination and post germination in seven lentil species.
Four seed germination phases including control or dry seed as well as one post-germination phase were defined in this study with six lentil species where phases I, II, and III occur during the seed germination, and phase IV is the post-germination phase. The genotype IG 72815 had the smallest seed size among the genotypes studied and CDC redberry had the largest seed size. Imbibition period was the longest for CDC redberry, while period of seed germination was less. For genotype with smaller seed size showed the opposite phenomenon.
The protease activity of all eight genotypes representing all lentil species began to increase during phase III, except for BGE 016880 in which protease activity started increasing in phase IV. For IG 72805 and IG 72815, the protease activity was the highest overall and then reduced in phase IV. The total essential and non-essential free amino acids released was the highest in phase IV. Among the genotypes studied, IG 110813, and IG 72623 had the highest amount of essential free amino acids (FEAAs) released during the germination phase. Among the FEAAs released, the amount of histidine was the highest followed by threonine. In phase IV, a significant increase was observed in theF EAAs isoleucine (ILE), lysine (LYS), leucine (LEU), valine (VAL), and threonine (THR) in germination phase IV.
Carbohydrate degradation was initiated right from the beginning as many of the enzymes were present in control seeds, and some of the enzymes were absent in phase IV presumably due to degradation. According to this study, phase III, most of the enzymes required for the tricarboxylic acid (TCA) cycle were present, which indicates the TCA became fully functional in phase III. Protein metabolism and synthesis related to enzymes and other factors was initiated in germination phase II. Neosynthesis of lipid catabolism, lipid biosynthesis, amino acid biosynthesis, protein modification, and protein translocation related proteins were initiated in phase IV.
Overall, this study found that germination phases III and IV were superior in terms of free amino acid release, and protease activity. Based on that observation, it could be concluded that phase III and phase IV were better in terms of digestibility and availability of as the protease activity and released free amino acids were found the highest in these phases. Based on proteome study it could be concluded that carbohydrate degradation followed by protein metabolism initiates seed germination phenomenon
Impact of Glucocorticoids on TNFα Responses after Pathogen- and Damage-associated Molecular Pattern Stimulation of Bovine Leukocytes
Get PDFInfectious diseases are responsible for significant economic losses to the livestock industry, affecting animal health, welfare, and performance. With increasing regulations against the use of antibiotics in livestock, there is a need to identify alternative strategies to minimize the susceptibility of animals to infection. While there is an appreciation that stress may impact susceptibility to infectious disease, there is contradictory evidence that stress can act to suppress or enhance immune activity and these immune consequences are influenced by type and duration of the stressor. Therefore, it is important to understand the functional consequences of stress on the immune system and the mechanisms by which stress alters immune function. To this end, we investigated the effect of stress on innate immune responses to molecules associated with pathogens and host cell damage. Bovine peripheral blood mononuclear cells (PBMCs) were stimulated ex vivo with lipopolysaccharide (LPS), peptidoglycan (PGN), and high mobility group box 1 (HMGB1), known agonists for pattern recognition receptors (PRR). The pathogen- and damage-associated molecular patterns (PAMPs and DAMPs, respectively) agonists, were used to simulate exposure to infection and host damage. These stimulations were performed either with or without PBMC pre-treatment with the prototypical stress hormone hydrocortisone to mimic a stress response. Tumor necrosis factor alpha (TNFα) release was used to quantify the innate immune response to each PAMP or DAMP and our results determined the kinetics of TNFα release in response to LPS, PGN, and HMGB1. Our study found increased release of TNFα after stimulation with all ligands, with a delayed response for PBMCs stimulated with PGN. Pre-treatment of cells with hydrocortisone significantly (p<0.05) inhibited TNFα release in a dose-dependent manner, but maximal corticosteroid inhibition was only ~50%. This plateau in corticosteroid inhibition was consistent with all PAMPs and the DAMP. These results demonstrate that a fraction of the TNFα released by bovine PBMCs following exposure to PAMPs and DAMPs can be inhibited by hydrocortisone, but this inhibition is not significant at the level of gene transcription. Our results suggest an acute stress response which elevates corticosteroids may partially inhibit TNFα responses induced by either pathogens or host cell damage. It remains to be determined whether this inhibition of PRR signaling results in increased susceptibility to infection and disease or reduces the risk of immune-mediated pathology
Biogenic greenhouse gas dynamics for wetland ponds in the Prairie Pothole Region of Canada
No full textThe abstract of this item is unavailable due to an embargo
Water source, climate, and water chemistry combine to influence DOC concentration and DOM quality in Buffalo Pound Lake, Saskatchewan
Get PDFFreshwater lakes and reservoirs are key components of the global carbon cycle. Dissolved organic matter (DOM) is an important water quality characteristic that regulates physical, chemical, and biological functions in these systems. Elevated DOM quantity, measured as dissolved organic carbon (DOC) concentration, and changes in DOM source and composition (DOM quality), create challenges for water managers already facing deteriorating sourcewater quality due to cultural eutrophication, climate-related uncertainty, and water scarcity. High DOC and variable DOM quality are a concern to drinking water treatment plants owing to their effects on disinfection byproduct formation, added costs for removal, and risks of bacterial regrowth in water distribution systems. In highly managed drinking water reservoirs like Buffalo Pound Lake, Canada, in the Great Plains of North America, understanding the effects of water source, climate, and in-lake water chemistry on DOM quantity and quality is of particular concern. Inflows to this reservoir are dominated by water releases from a large upstream reservoir (Lake Diefenbaker) with episodic influxes of runoff from the local catchment. Sourcewater variability to Buffalo Pound Lake depends on local hydroclimate, which fluctuates through periods of extreme wet and dry conditions. Long-term analyses demonstrated large fluctuations (> 10 mg/L) in monthly DOC concentrations over a 30-year period, and revealed the importance of flows from Lake Diefenbaker and the local catchment, and in-lake nutrient (total phosphorus and ammonium) and solute (sulfate) chemistry, on driving DOC in Buffalo Pound Lake. On a shorter timescale, measurements of DOM quantity and quality along the length of the lake, and across four open-water seasons when Lake Diefenbaker was the primary water source, clearly illustrated the role of internal production on altering DOM quantity and quality from lake inflow to outflow. We observed increases in DOC of up to 1–2 mg/L from the Buffalo Pound Lake inflow to outflow in all years, and several DOM quality metrics suggested a shift toward autochthonous DOM production as water transited through the reservoir. In dry years with greater water residence times, these patterns suggest that long, narrow Buffalo Pound Lake may act similar to a slow-moving river with respect to internal DOM production and processing. This work advances efforts to disentangle long-term drivers of DOC and understand DOM quality dynamics in this shallow eutrophic reservoir and across freshwater systems globally. Our results provide a foundation for DOM quantity and quality forecasting in Buffalo Pound Lake and will inform the design of an ongoing $325M upgrade to the Buffalo Pound Water Treatment Plant
ECUR318 Mini Lesson - Understanding the Odds: The Relationships Between Statistics and Gambling
No full textNon-Peer ReviewedA Mini Lesson/Professional Development designed to inspire Secondary Mathematics teachers to incorporate statistics-based games into their classrooms