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Turning the Tide: Adaptive Reuse in Response to Anthropogenic Climate Change
No full textThis thesis looks at new forms of habitation within near speculative futures and climate imaginaries. The evolving climate crisis catalyzes this thesis: recognition and anticipation of these shifts inform the locations, needs, and functions for intervention in a speculated 2080. The intent is to shift our preconceived ideologies of lifestyle and habitation, both typology and location, in response to climate change. Global mappings will identify susceptible and advantageous locations for future habitation. The speculative intervention will be an adaptive reuse of the existing Johan Sverdrup complex, comprised of five oil and gas platforms, in the North Sea to express habitation on the oceans. The Norwegian oil complex fully re-imagined as a self-sufficient community addresses population displacement, economic strains, sustainable/biogenic construction, remediation, climate data collection, and renewable energies while fostering symbiotic relationships between human and non-human species and systems
The size of hoverfly mimics relative to their models and the potential role of size in the evolution of mimicry
No full textBody size has received little attention as a mimetic trait, despite evidence that predators can discriminate mimics and models based on size. This thesis aims to explore the potential role of size in the evolution of mimicry. More specifically, it will investigate if mimics that are readily discriminable in size from their models experience reduced selection on colour pattern similarity. Firstly, we investigated if selection on colour similarity would decrease when size was highly discriminable for computer-generated prey and results indicated that when mimics and models were highly discriminable in size, there was less selection on colour. We then also investigated if there was a relationship between mimetic fidelity and the size of mimics relative to their model in hoverflies (Diptera: Syrphidae). No significant relationship between mimetic fidelity and relative size was found; instead a positive relationship between mimetic fidelity and the size of their hymenopteran models was found
Study of High Voltage Breakdown in Liquid Xenon Time Projection Chambers and Statistical Interpretation of Machine Learning Assisted Event Discrimination in Rare Event Searches
No full textNeutrinoless double beta decay (0νββ) is a hypothetical process with major implications for Beyond Standard Model physics. Its discovery would reveal the Majorana nature of neutrinos and provide insights into the neutrino mass ordering. The EXO-200 experiment, part of the Enriched Xenon Observatory (EXO) series, used a liquid xenon (LXe) detector to search for 0νββ. EXO-200 made the first measurement of two-neutrino double beta decay (2νββ) in Xe136 with T_2νββ_1/2 = 2.165 ± 0.016(stat) ± 0.059(sys) × 10^21 years, and set a limit on 0νββ half-life, T_0νββ_1/2 > 3.5 × 10^25 years at 90% confidence. nEXO is the next generation successor to EXO-200, operating with 5 tonnes of LXe. nEXO is expected to reach a sensitivity of T_0νββ_1/2 > 1.3×10^28 years at 90% confidence, further probing neutrino mass questions. Despite its success, EXO-200 encountered some challenges with detector high voltage (HV) instabilities. In response, the EXO-100 R&D cryogenic facility was conceived to study these issues. This work presents the recommissioning and upgrading of EXO-100, as well as its use to study HV instabilities. A correlation between instabilities and breakdowns in the detector is established. Further studies and simulations are conducted to investigate possible origins of HV instabilities in LXe detectors. These studies are used to understand the instabilities in EXO-200 and inform HV system design for the nEXO detector. Machine learning (ML), particularly the development of deep neural networks (DNNs), is increasingly important in particle physics, including the data analysis of rare-event searches. DNNs have proven to be very performant and versatile and enhance the sensitivity and discovery potential of these experiments. Modern analysis approaches are orienting towards the use of DNNs end-to-end, with low-level detector information as input, and a physics results as output. However, DNNs are black boxes, and often lack interpretability, complicating error assignment to outputs. This work examines this problem in detail for ML classifiers. The negative log likelihood (NLL) for the distribution of classifier outputs is inferred from Monte Carlo (MC) simulations. Minimizing the NLL provides an estimate for the number of signal events and a confidence interval, accounting for both statistical and systematic errors
The Quantity and Quality of Fathers' Shared Book Reading Practices
No full textThe present thesis sought to expand upon previous literature by examining both the quantity and quality of fathers’ shared reading practices through two separate studies. In Study 1, relations between fathers’ shared reading frequency and children’s vocabulary skills were examined. Fathers’ storybook exposure, along with mothers’ storybook exposure and parent education, explained 22.3% and 18.8% of the variances in receptive and expressive vocabulary, respectively, but were not unique predictors of either measures themselves. In Study 2, father-child interactions during shared reading were investigated. Partial evidence for a link between fathers’ and children’s linguistic complexity during shared reading was revealed. Additionally, patterns of father-child shared reading interactions indicated that both fathers and children were highly engaged in the reading process and that fathers used a variety of strategies to direct the reading session. Together, the findings from these studies provided a more comprehensive understanding of fathers’ shared reading practices
Bank Panics, Golden Grains, and Gold Standards: Essays on North American Macroeconomic History
No full textThis dissertation is the culmination of three research projects on North American Macroeconomic History. The first two Chapters analyze the effects of deflation on the financial sector and the real economy. Chapter 1 looks at the U.S. experience between 1868 and 1913, and Chapter 2 looks at the Canadian experience between 1867 and 1913. The 3rd Chapter also looks at Canada between 1876 and 1913, but instead of inflation, it examines the "Wheat Boom" and attempts to gain a new understanding of its nature, cause, and scale. Chapter 3 also offers a preliminary discussion on how the Wheat Boom is related to the historical mistreatment of Indigenous peoples in Canada. Combined, these three works used a mixture of econometric techniques, data analysis, analytic narrative, and a little bit of modeling, to better understand North America's economic history pre-1913
Culling Game Fish Angled in Freshwater Systems: Best Practices for Retention and Barotrauma Mitigation
No full textWhile many aspects of catch-and-release angling have been well-studied, less attention is placed on catch-hold-release scenarios, though these include comparatively more interaction between anglers and fish. In this thesis, I aimed to create actionable science in the freshwater recreational fisheries realm that could inform management practices or angler behaviour during retention. In Chapter 2, I investigated the practice of holding northern pike on a particularly damaging retention gear, stringers, finding high mortality rates and sublethal effects. In Chapter 3 and 4, I studied barotrauma mitigation in freshwater, an injury that is exacerbated by surface retention. While Chapter 3 suggested fizzing was favourable over descending for walleye with barotrauma, Chapter 4 revealed buoyancy issues in smallmouth bass after fizzing. In all, the chapters forming this thesis confirms that angler practice affects the wellbeing of released fish and provides recommendations for anglers in different retention situations
Long-Term Impacts of Bupropion Exposure during Critical Developmental Periods on Reward Learning
No full textPharmacological management of ADHD symptoms in children and adolescents has become a first-line treatment despite risk of misdiagnosis/over-prescription. Unnecessary exposure to psychotropics can disrupt brain development, producing maladaptive behavioural output. Bupropion (BUP) is a norepinephrine and dopamine reuptake inhibitor prescribed off-label for juvenile ADHD. Short- and long-term effects of BUP during critical periods of postnatal development were evaluated to assess reward-related neurobehavioural outcomes. Rats were administered high- or low-dose BUP or saline from p18-24 (preadolescence) or p34-40 (peri-adolescence). Operant training, extinction, and progressive ratio tests were later conducted. BUP did not alter overall reward seeking, rather, it disrupted quality of stimulus-reward learning. Exposure to BUP during peri-adolescence had complex neurobehavioural effects including pronounced on-drug psychomotor response and off-drug stimulus discrimination deficits (inactive lever pressing) after inconsistent reward delivery, indicative of transient learning. Reduced nucleus accumbens thin spine density and DeltaFosB-labelling suggest desensitization to dopamine and norepinephrine as a possible mechanism
A Labor of Love: Resisting the Neoliberal Settler Colonial University through Counterstorytelling
No full textUniversities function as spaces where social regulation and control coincide with resistance, growth, and renewal. On the one hand, they are institutions built on advancing settler colonialism and maintaining exclusionary structures of power, hierarchy, and harm through various manifestations of racial capitalism. On the other hand, they are spaces that facilitate revolution and social transformation through knowledge exchange and political struggle. By examining universities through the lens of racial capitalism, I aim to uncover university strategies of repression, and student activist strategies of resistance through critical race counterstorytelling and critical feminist grounded theory. Using these methods, I capture a counterstory of the resistance and resilience of radical student activists at the University of Ottawa from 2017-2020. In conversation with other student activists, this counterstory serves as a bearing witness and a guide for activists and organizers in post-secondary institutions and beyond
Gender Roles and Women's Decision-Making Power in Transnational Migrants' Households: The Case of Guatemala
No full textMigration literature has examined the benefits and challenges associated with temporary migration from Latin America and the Caribbean to Canada; however, less attention has been directed to the wives and families of temporary foreign workers remaining at home. This study addresses this lacuna by focusing on the impact of male transnational migration from rural Guatemala to Canada on the lives of women who do not migrate. Drawing on ten semi-structured online interviews, I use the insights of gendered geographies of power (Mahler & Pessar, 2001; 2003) to analyze the impact of migration on gender ideologies, women’s agency and decision-making power in the household. I argue that while migration bends gender roles and involves men in household tasks, this does not translate into considerable gender role changes or more women's agency. An argument is presented for policy considerations to support Guatemalan women who do not migrate
Perceptions of Police Use of Force: The Influence of Inconsistencies, Victim Race, Defendant Race, and Situation Type on Mock-Juror Decision-Making
No full textThe current set of studies examined whether various factors influenced mock-juror decision-making for a use of force case with a police officer defendant. Study 1 examined the effect of the number of inconsistencies (3 vs. 9), victim race (White vs. Indigenous), and defendant race (White vs. Indigenous). Results showed that a higher number of inconsistencies and a White defendant elicited less favourable perceptions of the defendant and higher perceptions of guilt. Study 2 examined the effect of the type of emergency situation (mental health check vs. domestic violence), victim race (White vs. Indigenous), and defendant race (White vs. Indigenous). Results showed that a mental health check situation, an Indigenous victim, and a White defendant elicited less favourable perceptions of the defendant and higher perceptions of defendant guilt. Participant attitudes were also examined and found to be influential on decision-making. Implications of the findings and directions for future research are discussed