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- Item1H NMR metabolomics of stress(Lethbridge, Alta : University of Lethbridge, Dept. of Neuroscience, 2016) Kiss, Douglas A.; University of Lethbridge. Faculty of Arts and Science; Metz, Gerlinde A. S.Metabolomics provides a method to study the dynamics of cellular function by adopting a systems biology approach to the analysis of small molecule metabolites found in various bio-fluids and tissue locations. Chapters one and two of this thesis explore the theory behind metabolomics and reviews representative studies applying NMR metabolomics to neuroscience. Chapter three presents the results from an experiment investigating the alterations of metabolic by-products found in urine caused by both cumulative and remote ancestral prenatal maternal stress. Chapter four explores the results of a similar experiment where the liver tissue from offspring of either cumulative or remote ancestral prenatal maternal stress were analysed. Chapter five is a general discussion and conclusion of the results from both experiments and explores how both sets of results indicate an alteration in the stress response of the offspring.
- Item3D biomechanical quantification of piano motor skills(Lethbridge, Alta. : University of Lethbridge, Dept. of Kinesiology and Physical Education, 2021) Turner, Craig Patrick; University of Lethbridge. Faculty of Arts and Science; Shan, Gongbing; Visentin, PeterTo date, systematic biomechanical explorations of music performance have been scarce. In many human activities, movement science methodologies have helped accelerate the learning process, prevent injuries, improve teaching practices, and optimize performance outcomes. The current thesis postulates that a consideration of individualization with respect to biomechanics, anthropometry, and musical strategization can provide musicians with an approach to motor learning where outcomes may be optimized while simultaneously reducing risk of playing-related injury. The thesis is comprised of three case comparison studies using 3D motion capture, biomechanical modeling, and force plate measurements to quantify pianists’ motor behaviours in a variety of performance contexts. The framework established in the thesis is interdisciplinary and provides a model that aims to be “artful” in its efforts to ensure that its analyses of motor behaviours are sensitive to musical intentionality and, thus, can be relevant to musicians.
- Item8,893 kilometres of cooperation : applying Kingdon's model to the development of Canadian border security policy since 9/11(Lethbridge, Alta. : University of Lethbridge, Dept. of Political Science, c2009, 2009) Marcotte, Christina; University of Lethbridge. Faculty of Arts and Science; Hale, GeoffreyCanadian border security policies are largely shaped by the asymmetrical relationship that exists between Canada and the United States. American markets are the primary destination for over eighty percent of Canadian exports, creating an economic dependence highlighted in the days following 9/11. As wait times at the American border extended to sixteen hours the importance of the shared border came sharply into focus. To ensure Canada‟s economic security the Canadian government needed to develop policies that would satisfy the American need for physical security and the Canadian need for economic security. This thesis applies John Kingdon‟s policy streams model to demonstrate and explain the subsequent development of Canadian border security policies. It also examines the institutional context for border security policies and examines two case studies: the Container Security Initiative and NEXUS.
- ItemA comparative study of augmented features and other ensemble approaches for music genre classification(Lethbridge, Alta. : University of Lethbridge, Dept. of Mathematics and Computer Science, 2023) Shariat, Raad; University of Lethbridge. Faculty of Arts and Science; Zhang, John Z.; Kharaghani, HadiMusic genre classification is essential in the music streaming industry, with many recommendation systems relying on data mining techniques to accurately classify musical genres. However, classifying music genres is challenging due to the inherent diversity of music, even within a single genre. This diversity can make it difficult for machine learning models to classify music accurately, leading to the development of various techniques to improve the performance of these models. One such technique is ensemble learning, which combines the predictions of multiple models to improve the overall accuracy of the ensemble. In this thesis, we propose a new ensemble method called "Augmented Features," which combines the predictions of multiple models by augmenting the input features with additional derived features. This technique can improve the performance of ensemble models by providing additional information to the models, allowing them to capture the music data's complexity better. To evaluate the performance of our ensemble method, we conducted experiments on various music datasets combined with different feature selection techniques. We compared the results to those obtained using the base classifiers and other ensemble methods, including voting, blending, and stacking. Our results showed that the augmented features method repeatedly outperformed the different techniques, particularly on datasets with high dimensionality and complex relationships between features. It is hoped that this work will significantly contribute to ensemble methods and improve the performance of machine learning models in various applications.
- ItemA mixed-method study on understanding irregular migration to Canada through technology-mediated communication: YouTube as a case study(Lethbridge, Alta. : University of Lethbridge, Dept. of Geography and Environment, 2023) Nasser, Wael M. A.; University of Lethbridge. Faculty of Arts and Science; Young, JulieThis study assesses the content, quality, and reliability of YouTube videos about irregular migration to Canada which effect migration decision-making. Using quantitative and qualitative methods, 342 out of 4986 YouTube videos posted between November 2016 and December 2019 were analyzed. The study illustrates the vast array of information available on YouTube on different topics such as transportation to the border, Canadian immigration laws, and basis of refugee claims. The results highlight the need for policymakers and researchers to understand where information is coming from and how potential migrants perceive it. The study examined Canadian government's use of digital spaces, like YouTube, to deter irregular migration and correct misperceptions. The thesis proposes policy recommendations for effective information campaigns on YouTube and proactive monitoring of irregular migration. It also emphasizes the technology sector's significant role in irregular migration to Canada with its implications for both irregular migrants and the Canadian government.
- ItemA quantum accelerated approach for the central path method in linear programming(Lethbridge, Alta. : University of Lethbridge, Dept. of Mathematics and Computer Science, 2023) Adoni, Vijay; University of Lethbridge. Faculty of Arts and Science; Gaur, DayaThe central path method is a crucial technique used in the optimization of linear programs. The method relies on classical computation which hits its limit for large instances, generally used in practice, in terms of efficiency. In this thesis, a proposal is made to explore the use of quantum algorithms to enhance the central path method’s performance when solving linear programs. We will go through the potential benefits and limitations of replacing the iterative equation-solving step with the HHL quantum algorithm, the Newton’s step for solving a set of nonlinear equations, and converting the nonlinear set of equations to bilinear equations with the help of McCormick relaxations. The aim of this thesis is to perform extensive experimentation on several types of efficient instances using each of the proposed algorithms and to evaluate their effectiveness through numerical simulations to find a promising approach for the central path method.
- ItemA TTOP model of permafrost distribution in the boreal wetland environment of Whatì, NT, Canada(Lethbridge, Alta. : University of Lethbridge, Dept. of Geography, 2023) Vegter, Scott E.; University of Lethbridge. Faculty of Arts and Science; Bonnaventure, PhilipMost permafrost models in Canadian boreal forests are low resolution at a regional or continental scale. This study aims to understand the viability of a Temperature at Top of Permafrost (TTOP) model on a local scale in the boreal wetland environment of Whatì, N.T. The model utilizes independent variables of vegetation, topographic positioning index and elevation, with the dependent variable being ground surface temperature collected from 60 Ground Truthing Nodes (GTN). The model predicts that 29 % of the ground is underlain by permafrost by having a mean annual temperature of < 0 °C. Model accuracy is assessed at 62.5 % when compared to ground truthing sites. Most permafrost studies place Whatì in the extensive discontinuous zone estimating that between 50 % - 90 % of the ground is underlain by permafrost. The underestimation and low accuracy show that ground truthing and accuracy assessments in this environment are critical.
- ItemAbstractive multi-document summarization - paraphrasing and compressing with neural networks(Lethbridge, Alta. : University of Lethbridge, Dept. of Mathematics and Computer Science, 2020) Egonmwan, Elozino Ofualagba; University of Lethbridge. Faculty of Arts and Science; Chali, YlliasThis thesis presents studies in neural text summarization for single and multiple documents.The focus is on using sentence paraphrasing and compression for generating fluent summaries, especially in multi-document summarization where there is data paucity. A novel solution is to use transfer-learning from downstream tasks with an abundance of data. For this purpose, we pre-train three models for each of extractive summarization, paraphrase generation and sentence compression. We find that summarization datasets – CNN/DM and NEWSROOM – contain a number of noisy samples. Hence, we present a method for automatically filtering out this noise. We combine the representational power of the GRU-RNN and TRANSFORMER encoders in our paraphrase generation model. In training our sentence compression model, we investigate the impact of using different early-stopping criteria, such as embedding-based cosine similarity and F1. We utilize the pre-trained models (ours, GPT2 and T5) in different settings for single and multi-document summarization.
- ItemAbsurd realism in postmodern American fiction: Wallace, Pynchon, and Tomasula(Lethbridge, Alta. : University of Lethbridge, Dept. of English, c2013, 2013) Babalola, Titilola; Benzon, KikiIn this thesis, I examine absurd realism as a literary subgenre in postmodern American fiction. I define the concept of absurd realism, focusing on the features that characterize it as a postmodern subgenre. I also look at its relationship with other subgenres of literature such as realism, absurdism, magical realism, and satire. Through the analyses of three postmodern novels: David Foster Wallace’s The Pale King, Thomas Pynchon’s The Crying of Lot 49, and Steve Tomasula’s TOC: A New Media Novel, I illustrate how the features of absurd realism portray a postmodern world pervaded by boredom and chaos. I also consider how these texts convey the absurdity of human existence through the use of everyday characters, events, and setting. In summary, this thesis focuses on how the absurd occurrences and bizarre characters that exist within these books portray, in both literal and metaphoric senses, the complexity of the postmodern world.
- ItemAddiction, treatment, and evidence-based medicine(Lethbridge, Alta : University of Lethbridge, Dept. of Philosophy, 2016) Wilcox, Sean; University of Lethbridge. Faculty of Arts and Science; Brown, BrysonHow addiction is conceived has important practical implications for how addicts are to be treated. This paper argues that we have a horrible concept of addiction and that has led to horrible treatment results. Examining this concept’s history will show that its main components (especially the brain disease view and the loss of control hypotheses) were invented or assumed by social reformers about 200 years ago, and that they do not map onto the physical world in a rich and systematic fashion. Science has been used to promote these assumptions instead of ever substantively establishing them. There are treatment methods that have been shown to be effective, but these are rarely employed in standard practice. Instead, addicts are provided with interventions that have been shown to be ineffective. Continuing to offer addicts treatment modalities that do not work when there are interventions with proven efficacy, is medical malpractice.
- ItemThe adequacy of the retirement income system for retired middle-income Canadians(Lethbridge, Alta. : University of Lethbridge, Dept. of Political Science, 2022) Ebhomielen, Anderson Edo; University of Lethbridge. Faculty of Arts and Science; Hale, Geoffrey; Belanger, Yale D.Lower-income retired Canadians in income quintile one are well taken care of by the government’s income support system, while upper-income Canadians (income quintile five) typically have adequate income and investments in retirement. However, this thesis established that middle-income Canadians in income quintiles two, three, and four rely on a mix of retirement income sources to achieve sustainable pre-retirement living standards. Data analyses were used to determine the adequacy of the retirement income system. The thesis focused on selected periods of 2000, 2005, 2010, 2015, and 2018 and compared the performance of the RIS in Canada and across the selected provinces of British Columbia, Alberta, Ontario, Quebec, and Nova Scotia. This thesis established that the RIS is adequate for middle-income Canadians. Employment income during retirement has no significant relationship with the Gross Replacement Rate (GRR). The thesis confirmed that the RIS achieved its objectives through the various retirement income sources.
- ItemAdiabaticity of high strain rate compression testing using the Split Hopkinson Pressure Bar Apparatus(Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 1997, 1997) Walton, Frank Stewart; University of Lethbridge. Faculty of Arts and Science; Kaminski, DavidIn the development of explosively formed projectiles (EFPs), researchers are faced with the problem of testing prospective metals at high strain rates. So far it has been assumed that, relative to the cooling time, the deformation time is practically instantaneous indicating that the test is adiabatc: none of the heat generated within the metal is lost to conduction. In this paper we construct a model that subtracts out the effects of kinetic energy and uses specific heat as a function of temperature. In this way we can focus on the energy change in the specimen that can be attributed to temperature and determine just how adiabatic the high strain rate test is.
- ItemAdolescent religious disposition in Canada : an exploratory sociological analysis(Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 1995, 1995) Penner, James Allan; University of Lethbridge. Faculty of Arts and Science; Bibby, ReginaldTaking as a given the general decline of organized religion in Canada, this thesis attempts to document the present lack of commitment towards organized religion among adolescents. Four questions are explored: (1) how committed are Canada's adolescents toward organized religion relative to other social options? (2) to what degree has religious commitment amond Canadian adolescents shifted over time? (3) in what ways does adolescent religious commitment vary according to religious group? and (4) do adolescent religiosity patterns follows those of adults? The major finding of this study, based on national Project Teen Canada and Project Canada data, is that organized religion is seldom experienced or valued by the vast majority of Canadian youth. Furthermore, adolescent religious commitment decreased from 1984 to 1992. Conservative Protestants reported higher religious commitment than did other youth and adolescent religiosity generally reflected adult levels. Lastly, tentative evidence suggest that Canada may experience future social consequences if adolescent religious disinterest continues. Despite being tentative and exploratory in nature, it is believed that the thesis gives social scientists their first national, in depth, sociological analysis of Canadian youth and organized religion. As such the findings provide a solid launching pad for further research. The thesis concludes with a plea for innovative study of Canadian adolescent religiosity and offers a list of potential projects.
- ItemAdrenalectomy-induced neuronal degeneration : development of a novel animal model of cognitive dysfuntion and neurogenic treatment strategies(Lethbridge, Alta. : University of Lethbridge, Dept. of Neuroscience, 2010, 2010) Spanswick, Simon C.; University of Lethbridge. Faculty of Arts and Science; Sutherland, Robert J.Long-term adrenalectomy (ADX) results in a specific loss of dentate gyrus granule cells in the hippocampus of adult rats, occurring over a period of weeks to months. This loss of granule cells results in cognitive deficits in a number of tasks that depend on intact hippocampal function. The gradual nature of ADX-induced cell death and the ensuing deficits in cognition are similar to those experienced by patient populations suffering from a variety of pathological conditions. Here we present an animal model by which we use ADX to produce a loss of granule cells within the hippocampus of rats. We also provide experimental evidence for a treatment strategy by which the lost granule cells may be replaced, with the goal of functional recovery in mind.
- ItemAdults’ perceptions of words for exercise goals(Lethbridge, Alta. : University of Lethbridge, Dept. of Kinesiology and Physical Education, 2022) Wall, Hayley Robyn; University of Lethbridge. Faculty of Arts and Science; Pope, PaigeThe purpose of this research was to explore which exercise goal words adults’ perceived to be intrinsic and/or extrinsic, how these perceptions differed from those of SDT experts and whether goal orientation and gender played a role in these classifications. A cross-sectional, online survey was presented to SDT experts (n = 13) and general population participants (nmen = 123, nwomen = 188). Chi-Square tests were used to explore differences in perception of 118 words by expertise (general/expert), gender, and goal orientation. Within the general population, 46 words were perceived as intrinsic and 25 as extrinsic. Additionally, experts and general population participants differed significantly on 55% of words, men and women on 21% and differing goal orientations on 7%. Findings identified 71words that most participants perceived as intrinsic/extrinsic, therefore researchers can feel confident using. These findings also highlight 55 words that the general population’s perception contrasted theory and researcher’s perceptions.
- ItemAffine fusion tadpoles(Lethbridge, Alta. : University of Lethbridge, Dept. of Physics and Astronomy, 2015) Urichuk, Andrew; University of Lethbridge. Faculty of Arts and Science; Walton, Mark A.Fusion dimensions are integer-valued quantities equal to the dimensions of the spaces of conformal blocks, which describe the interactions of a conformal field theory (CFT). Our focus was on the Wess-Zumino-Witten models, a particularly interesting type of CFT, whose primary fields correspond to representations of affine Lie groups. Arguably, affine fusion tadpoles are the simplest g>0 fusion dimension, having only a single incoming field and g=1. We study the symmetries of the SU(N) tadpole and Verlinde formula with the intention of finding a non-negative-integer decomposition. Such a decomposition might be indicative of a combinatorial atom for fusion. From produced tables we found that tadpole values appeared to be polynomial in the level k. Several conjectures were made and we sketch a method obtaining general forms of SU(N) tadpoles via dominant weight sums.
- ItemAfrican Nova Scotian Youth Experience on the Island, the Hill, and the Marsh: A Study of Truro, Nova Scotia in the 1950s and 1960s(Lethbridge, Alta. : University of Lethbridge, Dept. of History, 2019) Millman, Peter; University of Lethbridge. Faculty of Arts and Science; MacDonald, HeidiThis thesis explores the lived experiences of African Nova Scotian youth and their memories of growing up in three neighbourhoods in Truro, Nova Scotia in the 1950s and 1960s. Five male and five female African Nova Scotians who were between thirteen and nineteen years of age in the 1950s and 1960s were interviewed about their experiences of community, education, religion, dating, popular culture, music, and racism. Their stories surrounding the six topics highlight memories of sorrow, joy, hardship, and resilience, shared to preserve the missing history of rural Black youth experience in Truro, Nova Scotia. Collectively, their stories revealed a distinct Black youth culture and an education system that both implicitly and explicitly discouraged their progress.
- ItemThe aging hippocampus : a multilevel analysis in the rat(Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2005, 2005) Driscoll, Ira; University of Lethbridge. Faculty of Arts and Science; Sutherland, Robert J.The purpose of the current thesis was twofold: (1) to examine various factors that might be contributing to age-related learning and memory deficits specifically related to the hippocampus, and (2) to validate our rat model of aging, employing a multilevel analysis. We found age-related deficits on both spatial and non-spatial hippocampus-dependent taks that were accompanied by structural alterations observed in vivo (volune, but not neuronal metabolic function) and post mortem (neuronal density and neurogenesis, but not synaptic or mitochondrial density). Furthermore, our results suggest that the observed hippocampal structural changes, named decreased volume and neurogenesis, predict learning and memory deficits, and both can be accounted for by neurogenic reduction. In addition, the above-mentioned pattern of age-related deficits closely resembles that seen in humans, suggesting the present rat version of aging to be a very useful model for investigating hippocampal aging in humans.
- ItemAgricultural vulnerability to drought in southern Alberta : a quantitative assessment(Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2007, 2007) Ren, Xiaomeng; University of Lethbridge. Faculty of Arts and Science; Xu, WeiAgricultural vulnerability is generally referred to as the degree to which agricultural systems are likely to experience harm due to a stress. In this study, an existing analytical method to quantify vulnerability was adopted to assess the magnitude as well as the spatial pattern of agricultural vulnerability to varying drought conditions in Southern Alberta. Based on the farm reported data and remote sensing imagery, two empirical approaches were developed to implement vulnerability assessment in Southern Alberta at the quarter-section and 30 meter by 30 meter pixel levels. Cereal crop yield and the Standardized Precipitation Index (SPI) were specified as the agricultural wellbeing and stress pair in the study. Remote sensing data were used to generate cereal crop yield estimations, which were then implemented in vulnerability quantification. The utility of the remote sensing data source for vulnerability assessment were proved. The spatial pattern of agricultural vulnerability to different severity and duration of drought were mapped.
- ItemThe agronomic benefit of pulp mill boiler wood ash(Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2001, 2001) Patterson, Shane; University of Lethbridge. Faculty of Arts and Science; Thomas, James E.; Acharya, SuryaLand application of wood ash is becoming more appealing, as a disposable alternative, to landfilling options. It is estimated that 110,000 tonnes of wood ash is produced annually in Alberta by cogeneration systems, a large percentage produced in Central and Peace River Regions of Alberta. Alkaline (pH-13) properties and nutrient content of wood ash provides an alternative for the acidic and nutrient deficient soils within these regions. The objective of this field study was to determine the effect wood ash applications would have under field conditions on: the chemical and physical properties of soils; barley dry matter production; grain and seed yield of barley and canola; and the nutrient and metal uptake by crop tissue. Ash applications significantly increased dry matter and seed yield, improved crop nutrient quality, increased soil pH and improved soil nutrient availability, while not infringing on any environmental regulations.