HARVEST
University of Saskatchewan's Repository for Research, Scholarship, and Artistic Work
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Securitization theory and its empirical application: A literature review
(Revista de Sociologia e Política, 2024) Cordeiro Viana e Silva, Caroline; Pereira, Alexsandro Eugenio
Introduction: Securitization theory posits that securitization happens when actors frame political agenda issues as existential threats through their discourse, prompting states to take action in response. This article explores the challenges in the empirical application of the Copenhagen School's securitization theory in International Relations research.
Materials and methods: We conducted a systematic review of articles published in journals indexed in the Scopus database with an impact factor in the first quartile. Initially, we selected 260 articles that mentioned the term “securitization/securitisation” in their titles, abstracts, or keywords. After excluding those lacking an empirical application of securitization theory, 184 articles remained. We then carried out a content analysis of the logical structure of these articles' arguments, categorizing how each one applied the concept of securitization according to the stages of the process (non-politicized, politicized, securitized, securitizing actor) and its variables.
Results: Out of the 184 articles, 110 set out to apply securitization theory, but only 11 successfully did so in a way that clearly confirmed securitization. These 11 studies showed how topics were securitized by following the stages outlined in the original theoretical framework.
Discussion: The challenges in empirically applying securitization theory arise from two main factors: the researchers themselves and the theory itself. Many articles faced methodological hurdles and lacked rigor in operationalizing the theoretical elements required to confirm the securitization of a topic, revealing limitations among the researchers. Additionally, the theory demands a high level of empirical evidence, which makes its application more difficult. This indicates a need to revisit the theory and consider integrating models that facilitate empirical studies on securitization.
Tyrosine Hydroxylase–Positive Nucleus Accumbens Neurons Influence Delay Discounting in a Mouse T-Maze Task
(eNeuro, 2024-12) Appings, Ryan; Botterill, Justin J; Zhao, Mudi; Riaz, Sadia; Kanani, Asa; Violi, Francesca; Steininger Jr., Carl Frank David; Ito, Rutsuko; Arruda-Carvalho, Maithe
Delay discounting (DD) is a phenomenon where individuals devalue a reward associated with a temporal delay, with the rate of devaluation being representative of impulsive-like behavior. Here, we first sought to develop and validate a mouse DD task to study brain circuits involved in DD decision-making within short developmental time windows, given widespread evidence of developmental regulation of impulse control and risk-taking. We optimized a T-maze DD task for mice that enables training and DD trials within 2 weeks. Mice learned to choose between a large and a small reward located at opposite arms of a T-maze. Once training criteria were met, mice underwent DD whereby the large reward choice was associated with a temporal delay. Task validation showed that adolescent C57BL/6J mice display an increased preference for the small reward upon a temporal delay, confirming increased impulsivity compared with adults. We next used this DD task to explore the neural basis of decision-making. We used tyrosine hydroxylase transgenic mice (TH-Cre) to target TH-positive neurons in the nucleus accumbens (NAc) and ventral tegmental area (VTA) with Cre-dependent excitatory or inhibitory designer receptors exclusively activated by designer drugs (DREADDs). Inhibition of transduced neurons in the NAc decreased preference for the small but immediate reward during DD. Inhibition of TH-positive neurons in the ventral tegmental area (VTA) did not affect impulsive choice in this DD task. These results uncover a novel role for NAc TH-positive neurons in DD behavior and expand the repertoire of behavioral tasks available for studying decision-making across the lifespan.
Cancer Cell’s Achilles Heels: Considerations for Design of Anti-Cancer Drug Combinations
(International Journal of Molecular Sciences, 2024-12) Gahramanov, Valid; Vizeacoumar, Frederick Sagayaraj; Morales, Alain Morejon; Bonham, Keith; Sakharkar, Meena K.; Kumar, Santosh; Vizeacoumar, Franco; Freywald, Andrew; Sherman, Michael
Loss of function screens using shRNA (short hairpin RNA) and CRISPR (clustered regularly interspaced short palindromic repeats) are routinely used to identify genes that modulate responses of tumor cells to anti-cancer drugs. Here, by integrating GSEA (Gene Set Enrichment Analysis) and CMAP (Connectivity Map) analyses of multiple published shRNA screens, we identified a core set of pathways that affect responses to multiple drugs with diverse mechanisms of action. This suggests that these pathways represent “weak points” or “Achilles heels”, whose mild disturbance should make cancer cells vulnerable to a variety of treatments. These “weak points” include proteasome, protein synthesis, RNA splicing, RNA synthesis, cell cycle, Akt-mTOR, and tight junction-related pathways. Therefore, inhibitors of these pathways are expected to sensitize cancer cells to a variety of drugs. This hypothesis was tested by analyzing the diversity of drugs that synergize with FDA-approved inhibitors of the proteasome, RNA synthesis, and Akt-mTOR pathways. Indeed, the quantitative evaluation indicates that inhibitors of any of these signaling pathways can synergize with a more diverse set of pharmaceuticals, compared to compounds inhibiting targets distinct from the “weak points” pathways. Our findings described here imply that inhibitors of the “weak points” pathways should be considered as primary candidates in a search for synergistic drug combinations.
Understanding links between flow regime and fish populations in the Saskatchewan River Delta
(2025-01-17) Twilley, Jackie Tennille; Jardine, Timothy; Enders, Eva; Paul, Andrew; Smokorowski, Karen; Robson, James
Successful spawning and survival to adulthood (i.e., recruitment) are essential to maintain sustainable fish populations. Abiotic environmental conditions can influence recruitment and the resulting ability to harvest adult fish. In rivers, the flow regime dictates water depths and velocities that subsequently trigger spawning and enable the survival of juveniles. However, anthropogenic activities such as the operation of hydroelectric generating stations can change the natural hydrograph with effects on physical and biological processes. I investigated the relationship between the river flow regime and sustainable fish population sizes for two species of economic and cultural importance (Walleye Sander vitreus and Lake Sturgeon Acipenser fulvescens) in the Saskatchewan River Delta. To estimate the annual recruitment of Walleye, aging structures were removed from fish sampled from the commercial fishery at Cumberland Lake, Saskatchewan. Cohort strength was then estimated by assigning the year of hatch to individual fish. The cohort strength was compared against discharge from a gauge below the E.B. Campbell hydroelectric generating station, located ~100 km upstream from Cumberland Lake. I found a significant effect of hydrology with an estimated 69% increase (28–105% credible interval) in recruitment with every 100 m3·s-1 increase in discharge over the fry growth period (weeks 30–42) in Walleye. Also, based on the estimated Bayesian posterior distribution, there was a very high probability (p > 0.99) that the effect was different from zero. To estimate long-term harvest numbers for Lake Sturgeon, data was drawn from multiple sources (Hudson Bay Company records, government commercial fishery records, and recent mark-recapture programs). During the pre-dam (1774 to 1960) and post-dam (1965 to 2019) eras, the annual total harvest of Lake Sturgeon was estimated and compared to determine if harvest levels differed before and after flow modification. I observed no significant difference between the pre- and post-dam eras when all data was combined, but using only a subset of the 20th-century commercial catch data revealed a significant difference in Lake Sturgeon catch before and after dams were built. Discharge during the first ten years of the Lake Sturgeon’s life before recruitment to the fishery was a significant predictor of catch, but only when backdating to the period 25–35 years prior to catch and only when using more recent gauge data rather than tree-ring records. I found an estimated 59% increase in Lake Sturgeon catch with every 100 m3·s-1 increase in mean annual discharge. The study of these two species strengthens our understanding of the relationship between interannual and multidecadal changes in flow and fish population sizes, with implications for maximum sustainable harvest levels in the Saskatchewan River Delta. As upstream hydropower operations and irrigation withdrawals continue to alter spring and summer flows, data suggest that re-naturalization of the flow regime could improve recruitment of Walleye and Lake Sturgeon.
Classical and Quantum Algorithms for Deterministic and Stochastic L-System Inference Problems
(2025-01-17) Lotfi, Ali; McQuillan, Ian; McQuillan, Ian; Mondal, Debajyoti; Rayan, Steven
L-systems can model and simulate many biological processes, such as plant development. Experts typically construct an L-system for a given process by hand, which is hugely time-consuming.
It would be significant if this could be done automatically from data, such as from sequences of images.
We will focus on two kinds of L-systems in this thesis: deterministic and stochastic L-systems.
As the names suggest, deterministic L-systems generate a unique sequence, while stochastic systems generate a variety of sequences with certain probabilities.
The method of constructing an L-system from a given process could look different for deterministic and stochastic L-systems.
In the case of stochastic L-systems, interesting problems could include how to construct a stochastic L-system with the highest probability of producing such a process.
Approximate solutions and solutions which
utilize the power of quantum computing are also of interest.
In one chapter of this thesis, we will present novel theorems that address open problems
in stochastic Lindenmayer-system (L-system) inference. Specifically, we will discuss the construction of an optimal stochastic L-system capable of generating
a given sequence of strings. The first theorem proposes a method for constructing a stochastic L-system that has a derivation with the highest probability of producing a given
sequence of words. The second
theorem addresses the more difficult problem in this area; it offers the stochastic L-systems with the highest probability of
producing a given sequence of words through multiple possible derivations. Once we have set the foundation to analyze these problems, we will introduce an algorithm that constructs an optimal stochastic L-system from a given sequence. This algorithm utilizes sophisticated optimization techniques, ensuring the production of a stochastically
optimal stochastic L-system suitable for generating the given sequence. This allows for using stochastic L-systems as a model for machine learning, using only positive data for training.
In the second part of this thesis, we are interested in inferring a deterministic context-free L-system from a sequence of strings. We will first introduce the characteristic graph of a sequence of strings. This graph captures the restrictions that inference applies in a problem, which we then utilize to translate our problem (inferring D0L-systems) in polynomial time into the maximum independent set problem (MIS). This translation also offers a free translation of our problem into the SAT problem. After that, we provide a classical exact and approximate quantum algorithm for the problem. The quantum algorithm we will be presenting belongs to the family of QAOA (Quantum Approximate Optimization Algorithms), and its time complexity has a polynomial time complexity. This algorithm is the first quantum algorithm and is another witness to how vast quantum computing could be towards machine learning. Our result also offers nontrivial upper bounds on the number of distinct deterministic L-systems that may generate a sequence of strings.
Urban Renewal on the Prairies: A Comparison of Brandon and Saskatoon in the 1950s and 1960s
(2025-01-17) Lints, Alex; Clifford, Jim; Watson, Andrew; Engelbert, Robert
This thesis examines the processes of urban renewal and redevelopment in the context of the Canadian Prairies during the 1950s and 1960s. Using Brandon, MB, and Saskatoon, SK, as case studies, this work shows that smaller urban centres on the Prairies underwent similar changes to larger ones like Toronto and Vancouver, albeit with regionally different results. Both cities moved towards a new model of economic planning driven by urban renewal and development-based initiatives, facilitated by expanded planning departments. These cities also underwent ambitious, era-defining projects in the 1960s that defined their skyline for years to come. However, the key difference and most significant point this thesis makes is that the results of urban renewal in Brandon and Saskatoon provide an example where modernist ideals did not necessarily result in long term social issues and typical scenes of slum clearance as they did elsewhere.
Synthesis, Characterization, and Application of Dithiobiuret-Based Ligands for Coordination and Selective Extraction of the Coinage Metals
(2025-01-17) Proulx, Mario B. W.; Foley, Stephen R.; Grosvenor, Andrew P.; Gravel, Michel; Kelly, Timothy L.
The abstract of this item is unavailable due to an embargo.
Application of Large Language Models in Code Clone: Benchmarking, Evaluation and Detection
(2025-01-17) Alam, Ajmain Inqiad; Roy, Dr. Chanchal; Schneider, Dr. Kevin; Schneider, Dr. Kevin; Roy, Dr. Banani; Lehnert, Dr. Lucas
The abstract of this item is unavailable due to an embargo.
INVESTIGATING HEALTHCARE PROFESSIONALS’ AND DIETITIANS’ KNOWLEDGE ATTITUDE AND PRACTICES CONCERNING THE PROVISION OF CULTURALLY SAFE CARE TO MUSLIMS DURING RAMADAN
(2025-01-16) Hillier, Katherine A W; Vatanparast, Hassan; Lane, Ginny; Lieffers, Jessica; Labrecque, Mary Ellen; Bandy, Brian
The abstract of this item is unavailable due to an embargo.
LIPIDOMICS AND MEMBRANE AQUAPORINS IN BOVINE SPERM
(2025-01-16) Sarwar, Muhammad Kaleem; Benson, James; Anzar, Muhammad; Singh, Jaswant; Egydio de Carvalho, Carlos; Purdy, Phil; Gray, Jack; Buhr, Mary
Cryopreservation of bovine sperm leads to a significant reduction in post-thaw functionality, resulting in significant economic losses for the artificial insemination (AI) industry. Significant damage is inflicted on the sperm plasma membrane during this process. The current thesis investigated the relationship of sperm membrane aquaporins (AQP3 and AQP11) and lipidome in semen ejaculates of Bos taurus with sperm post-thaw motility (PTM). The first project localized and quantified both aquaporins using immunocytochemistry, western blotting and flow cytometry and correlated them with PTM. AQP3 was localized in the acrosomal region, whereas AQP11 was in the sperm tail with diffused localization in the sperm head. Both aquaporins showed positive correlations with PTM based on flow cytometry analysis, suggesting their potential as biomarkers for sperm PTM. The second project explored the lipid composition of bovine sperm, identifying 263 lipid species across 11 lipid classes. Phosphatidylcholine (PC), phosphatidylethanolamine (PE) and total lipid class content showed positive, while lyso-PC and glucosylceramide (GlcCer) showed negative correlations with PTM. The final project explored individual lipid expression in high and low PTM bull groups using a number of statistical methods. This study found that PC- and PE-conjugated polyunsaturated long-chain fatty acids were dominant in sperm lipids from high PTM bulls and may serve as biomarkers for PTM. On the contrary, most sphingomyelin (SM) and phosphatidylglycerol (PG) species were dominant in sperm lipids from low PTM bulls. This research may contribute to developing pre-freeze viability assays, lipid-based diets and modified extenders to improve sperm post-thaw survival by the AI industry.