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Functional Connectivity and Attention Abilities in Pediatric Populations
No full textAutism and Attention-Deficit/Hyperactivity Disorder (ADHD) are highly heterogeneous neurodevelopmental disorders (NDDs) that are associated with attention and executive function (EF) deficits (Neely et al. 2016; Craig et al. 2016). Despite EF and attention being common deficits, groups of individuals with Autism and ADHD are not easily differentiated from each other or from controls by measures of attention and EF (Cai et al., 2021; Kushki et al., 2019). The process for diagnosis of Autism and ADHD is long and requires considerable resources. To make this process more efficient, a better understanding is required about the types of assessments and cognitive domains that contribute more or less to diagnostic status (which will be explored in Chapter 2). The search for neural correlates of Autism and ADHD, such as differences in functional connectivity (FC) related to diagnostic status, has resulted in highly inconsistent results (Cortese et al., 2021; Liloia et al., 2024). This could, in part, be due to the heterogeneity of symptom severity and presentation in Autism and ADHD (Luo et al. 2019; Dajani et al. 2016). By assessing the neural correlates of specific attention and EF measures transdiagnostically, there may be more consistency in results (Mooney et al., 2024). In the search for neural correlates it is also important to acknowledge the factors that could also influence the brain-behaviour relationship, such as stimulant medication (Schweren et al., 2016; Swanson et al., 2011) (further explored in Chapter 3), or diagnostic status (Zhang et al. 2024) (explored in Chapter 4). The lack of consideration for these factors could also contribute to a lack of convergence in results, thus it is important to understand the factors that could influence the brain-behaviour relationship
Snow Depth on Sea Ice in the Canadian Arctic: Spatiotemporal trends and estimation from multi-satellite remote sensing
No full textIn this thesis, I investigate the spatiotemporal variability and satellite-based estimates of snow depth on landfast first-year sea ice in the Canadian Arctic Archipelago. Based on long-term in-situ measurement records of snow depth on sea ice, I present its seasonal and interannual trends and variability. I further investigate the contributing factors of snow accumulation on sea ice in the Canadian Arctic Archipelago under the context of warming temperatures and climate change. The mean seasonal rate of snow accumulation on sea ice from September to April is 3.2 ± 0.6 cm month-1 across the Canadian Arctic. Snow accumulates differently on sea ice and on land in autumn differ due to the lag between the freeze-up and the first snow of the season. To investigate satellite-based estimates of snow depth on landfast sea ice in the Canadian Arctic, I analyse near-coincidental satellite altimetric and synthetic aperture radar (SAR) acquisitions, as well as in-situ measurements of snow depth and snow properties collected during a dedicated campaign to compare field and satellite-based observations of the snow and ice conditions in Dease Strait, Nunavut. The elevation difference measured by the two altimeters demonstrates the variability of snow depth along the satellite acquisition track. A statistically significant correlation is found between SAR backscatter coefficients at C-band and altimetric backscatter coefficients at Ku-band, where there is low snow depth and a smooth ice surface topography
Impacts of sedimentation on early-life phenotypes and gene expression in coho salmon (Oncorhynchus kisutch)
No full textEarly-life environmental stressors may threaten species of conservation concern by impacting populations during vulnerable early life history stages. Here, I tested some of the effects of sediment stress and hypoxia during early-life development on phenotypic outcomes and gene expression in coho salmon (Oncorhynchus kisutch). I obtained O. kisutch eggs from the Sugsaw Hatchery located on Vancouver Island, BC, and reared them in one of three substrate (0% fine sediment, 10% fine sediment, 20% fine sediment) or one of two no substrate (normoxia/100% DO or hypoxia/50% DO) treatments to the alevin stage (n=180 per treatment). Survival did not differ between groups, but fish reared in hypoxia and 20% fine sediment exhibited significantly lower fork lengths and weights. Yolk sac area and volume were also lower in fish from the 20% fine sediment treatment, suggesting a decrease in yolk sac conversion efficiency. Gene expression analysis of three general (HIF1A_6, ALD_1, HemA1_1) and four hypoxia-specific (Anillin, Ncapd3, Ndc80, Kif4) biomarkers revealed significant upregulation of ALD_1 expression in hypoxia-reared fish, while fewer significant differences were detected in the remaining biomarkers. Overall, more research is necessary to elucidate the genomic mechanisms mediating the phenotypic changes that result from exposure to hypoxia and high sedimentation in early-life salmonids. Yet these findings suggest that there may be negative consequences of sedimentation and hypoxia during early-life salmonid development and that these are driven by complex molecular interactions that underlie early-life organisms’ responses to stress. Reduced growth and yolk sac conversion efficiency in fish reared without substrate, compared to high quality substrate further suggest that substrate environmental enrichment (EE) during early-life rearing may be beneficial for salmonids artificially reared in hatcheries
Alberta Gambling Research Institute Conference 2025: Insight to Impact Advances in Gambling Research
No full textThe Institute’s 2025 Conference "Insight to Impact Advances in Gambling Research" took place April 24-26, 2025 at The Banff Centre in Banff, Alberta as a live event. A selection of conference presentations presented at the event have been made available with the permission of the authors.Alberta Gambling Research InstituteAlberta Gambling Research Institut
Gender and Ministerial Appointments in Africa.
No full textThis dissertation examines the gendered dynamics of ministerial appointments in Africa, focusing on the vetting process, patterns of portfolio allocations, and cabinet shuffles. The process of appointing cabinet ministers is shaped by both formal and informal rules (Annesley, Beckwith, and Franceschet 2019). While formal rules grant presidents the authority to select ministers, informal norms often constrain their choices (Franceschet 2016). In some contexts, formal rules include confirmation hearings, which enable legislative oversight and public scrutiny (Heitshusen 2015). Despite extensive research on confirmation hearings in Western democracies (Canes-Wrone and De Marchi 2002; Krutz, Fleisher, and Bond 1998), little attention has been paid to how these processes operate in African contexts or whether they are gendered. To address this gap, Chapter One analyzes ministerial confirmation hearings in Ghana and Kenya. The findings reveal that women nominees face greater scrutiny concerning personal appearance and ethical standards than their male counterparts. Building on vetting process, Chapter Two shifts focus to patterns of portfolio allocation across 25 African countries. Recent data shows women hold 23.8% of cabinet positions in Africa, slightly above the global average of 22.8% (Inter-Parliamentary Union 2024; UN Women 2024). However, the criteria for being considered ministrable often include educational and professional backgrounds and political experience (Annesley, Beckwith, and Franceschet 2019). I find that, contrary to expectations, among the women ministers appointed, a higher proportion are assigned to high-prestige portfolios compared to men. Having established the vetting process of minister and portfolio allocations, Chapter Three focuses on cabinet shuffles to address what happens once they are in office. These intra-term changes, made to manage coalitions, consolidate power, or respond to political and economic shocks (Grotz, Kroeber, and Kukec 2022; Helms and Vercesi 2022), often produce gendered outcomes. The findings show that women in Africa serve shorter terms and are more likely to be replaced by men during shuffles. In sum, this dissertation uses a mixed methods approach to study the gender dynamics of ministerial appointments across Africa. By examining confirmation hearings, portfolio allocation, and cabinet shuffles, it advances our understanding of how gender influences political appointments in Africa
The influence of two physical activity programs on bone and muscle health in youth with cerebral palsy and other neuromotor impairments.
No full textWeight-bearing physical activity is crucial for building strong bones, especially during childhood and adolescence when bones grow rapidly. During this time, physical activity, muscle-bone interactions, and gravity help stimulate bone development. However, in conditions that limit mobility, such as cerebral palsy (CP) and other non-progressive neuromotor impairments (CP-like), physical activity is reduced, which can lead to poor bone health. This increases the risk of fractures and may lead to osteoporosis in adults with CP. This thesis examines bone health in children and youth with CP and CP-like conditions using peripheral quantitative computed tomography (pQCT) scans of the tibiae. Bone and muscle parameters, including bone mineral content (BMC), bone mineral density (both trabecular and cortical; BMD), bone size, and muscle size, were compared to age-, sex-, and ethnicity-matched peers from a typically developing population. A total of 22 participants from all Gross Motor Function Classification System (GMFCS) levels (I-V) were included. This study found smaller, thinner and weaker bones and lower muscle strength in children and adolescents with CP and CP-like conditions across all GMFCS levels, with deficits relating to functional ability. As weaker bones increase the incidence of fragility fractures, causing pain and predisposing future comorbidities, this thesis further evaluated the effects of two physical activity programs on bone and muscle strength. Robot-assisted walking in three participants with the greatest functional limitations found upright mobility may improve bone strength. In contrast, power training in eight participants with the greatest functional abilities found no adaptations in bone or muscle. These findings suggest that while bone health is a concern across all functional abilities, adaptations appear to correlate to the loading one previously experienced, having the greatest impacts in those who do not regularly ambulate. This highlights the importance of tailored physical activity programs based on functional ability during growth and could inform strategies for improving musculoskeletal health in children and youth with CP and CP-like conditions
Computed Tomography–Based Finite Element Modeling of the Rabbit Hindlimb
No full textAnimal models are an essential pillar of orthopaedic research. Rodents, in particular, have played a pivotal role in developing our current understanding of bone mechanobiology, but they lack the Haversian systems found in human bone. For studies of mechanobiology and in line with FDA recommendations, researchers are turning to larger animal models, like rabbits, which naturally exhibit intracortical remodeling. Our group has developed a non–invasive, in vivo rabbit tibial loading model to establish the relationships between applied load, strains, microdamage accumulation, and bone remodeling. To capture the strain environment, we require a validated computed tomography (CT)–based finite element (FE) model of the rabbit hindlimb. To this end, we first established the density–elasticity relationships for rabbit hindlimb bones. By using well defined experimental boundary conditions for in silico replication, we were able to optimize the density–elasticity power law constants such that the resulting FE models provided strain predictions that were strongly correlated with experimental measurements (0.85 ≤ R2 ≤ 0.96). With the ability to accurately assign heterogeneous material properties, the derived relationships were used in CT–based FE models of the rabbit hindlimb. Early findings revealed that FE strain predictions were exceptionally sensitive to the assumed force vector orientation, and increasing the model complexity would be futile. Instead, we developed an experimentally informed optimization approach to determine the individual force vector orientations that minimized the error between FE predicted and experimentally measured bone strains. This resulted in statically equivalent FE models that explained up to 96% of the variation in experimental strain mesurements. Our work serves to guide future in vivo rabbit hindlimb loading studies and enable the use of computational models in the investigation of bone mechanobiology
Understanding the experiences of young, urban, Indigenous mothers-to-be in British Columbia, Canada
No full textAbstract Background Indigenous Peoples comprise the youngest and fastest growing demographic in Canada, with many living in urban-suburban areas. Given higher fertility rates, younger overall ages and higher adolescent pregnancy rates, perinatal research is needed—to inform policymaking and programming throughout pregnancy and childhood. Yet such data remain scarce in British Columbia (BC), Canada. This study therefore aimed to describe the experiences of young, urban, Indigenous mothers-to-be who enrolled in a larger BC early prevention trial designed to reach families experiencing socioeconomic disadvantage. Methods This descriptive study utilized baseline data from a trial that enrolled first-time mothers-to-be who met indicators of socioeconomic disadvantage and who were residing in select urban-suburban areas. These indicators included being young (19 years or younger) or having limited income, low access to education, and being single (aged 20−24 years). We described and compared survey data on girls (n = 109; aged 14−19 years) and young women (n = 91; aged 20−24 years) using Chi-square or Student’s t-tests. Results Of the 739 trial participants, 200 or 27% identified as Indigenous and met trial eligibility criteria: limited income (92.9%), limited access to education (67.0%), and/or being single (90.9%). Beyond this, participants reported associated adversities including: unstable housing (63.3%), psychological distress (29.3%), severe anxiety or depression (48.5%), experiences of childhood maltreatment (59.4%) and intimate partner violence (39.5%). Compared to girls, young women reported higher income and educational attainment (p < 0.001), more unstable housing (p = 0.02) and more childhood maltreatment (p = 0.014). Many had recently received primary healthcare (75%), but few had received income assistance (34%). Most (80.5%) reported experiencing four or more adversities. Conclusions We present data illustrating that a high proportion of pregnant Indigenous girls and young women engaged with public health and consented to long-term research participation—despite experiencing cumulative adversities. The trial socioeconomic screening criteria were successful in reaching this population. Girls and young women reported relatively similar experiences—beyond expected developmental differences in income and education—suggesting that adolescent maternal age may not necessarily infer risk. Our findings underscore the need for Indigenous community-led services that address avoidable adversities starting in early pregnancy
Examining factorial validity and internal consistency of Professional Quality of Life (ProQoL-9) among care aides working in Long-term Care (LTC)
No full textAbstract Background The ProQoL (30 items) is a widely used instrument of work-related quality of life for health care workers. Recently, a shorter 9-item version of the ProQoL was developed and validated among palliative care workers. The ProQoL-9 consists of three subscales: compassion satisfaction (CS), burnout (BO), and compassion fatigue (CF). Care aides (personal support workers, nursing assistants) are an understudied population in terms of their professional quality of life. It is critical to use validated instruments to measure their experiences. The purpose of this study was to examine the internal consistency and factorial structure of the ProQoL-9 among care aides working in LTC. Methods We used surveys collected by the Translating Research in Elder Care (TREC), a pan-Canadian program that collects longitudinal surveys from the healthcare workforce in the LTC. We used TREC surveys containing information on demographics, characteristics of LTC homes (e.g., ownership model), and the ProQoL-9. Our sample included all care aides who completed TREC surveys in the province of Alberta, Canada, from 2020–2021. We examined internal consistency via alpha and omega coefficients. To examine the factorial structure, we conducted confirmatory factor analysis (CFA) testing one factor, two factors (CF and BO together & CS), and three factor models (CF, BO, and CS). Results N = 760 care aides completed the surveys in Alberta. The majority were female (90.79%) and worked in general LTC units (55.29%). The Cronbach’s alpha results showed an overall α = 0.56 for the whole scale and adequate reliability of the subscales (α = 0.73 for CS, α = 0.68 for CF, and α = 0.75 for BO). The omega reliability results for all the subscales were ≥ 0.70, reflecting good internal consistency (BO = 0.77, CS = 0.73, and CF = 0.70). The three-factor model had the best goodness of fit values, reflecting an adequate goodness of fit (X2 = 165.82, DF = 24, X2/DF = 6.9, P < .0001, RMSEA = 0.08, CFI = 0.92, TLI = 0.89). Conclusions The ProQoL-9 is a valid and reliable instrument among care aides in LTC. The factorial structure shows that this shorter version of the ProQoL is rigorously designed and can be utilized by health service researchers in LTC
Development and Characterization of Catalysts for Fuel Cell and CO2 Electrolyzer Applications
No full textThis thesis explores advanced catalysts for energy conversion, focusing on two key projects. The first project explores doped PtRu catalysts to improve CO tolerance in proton exchange membrane (PEM) fuel cells. Using density functional theory (DFT), Pd- and Rh-doped PtRu catalysts were identified as promising due to their resistance to CO poisoning. These findings suggest the potential to enhance PEM fuel cell anode durability and reduce fuel purification requirements, though experimental validation is needed. The second project focuses on nitrogen-doped carbon catalysts for electrochemical CO2 reduction (CO2RR). Jialang Li’s thesis ([86]) demonstrated that nitrogen doping lowers the energy barrier for CO2 reduction, enhancing catalytic activity. In my study, both Vulcan XC 72-R and CIC-85 were investigated. Untreated carbon black (Vulcan XC 72-R) and CIC-85 were found to be inactive for CO2RR. Acid treatment increased the surface oxygen content but did not significantly enhance catalytic activity. However, when acid-treated Vulcan car- bon or CIC-85 was subjected to high-temperature ammonia treatment, substantial nitrogen doping was achieved, as confirmed by advanced surface characterization techniques. My results show that increased oxygen content from acid treatment facilitated greater nitrogen incorporation during ammonia doping, significantly improving CO2RR activity and selectivity. These findings highlight the role of oxygen content in enabling higher nitrogen doping and improving performance for CO2 reduction. These results contribute to both theoretical and experimental advancements in the development of catalysts for sustainable energy applications