University of Lethbridge Theses

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    Exploring sulfate cycling in a mineral-soil wetland restored with wastewater
    (Lethbridge, Alta. : University of Lethbridge, Dept. of Biological Sciences, 2024) Denny, Mariya; University of Lethbridge. Faculty of Arts and Science; Bogard, Matthew J.
    Sulfate (SO42-) pollution is contributing to the salinization of surface waters worldwide. Wetlands are natural filters on the landscape that remediate surface water by retaining and processing pollutants. However, the capacity for wetlands to process excess SO42- from wastewater is poorly understood, especially for natural (as opposed to constructed) wetlands. Here, I explore the SO42- remediation capacity of Frank Lake, a restored, multi-basin wetland complex in southern Alberta, Canada, that is used to treat effluent from municipal and beef slaughterhouse sources. Using a combination of approaches, I show that there was limited SO42- processing throughout the wetland. Mass balances constructed for two distinct hydrologic periods showed that Frank Lake shifted from a SO42- source during wet years (2013 - 2015) to a sink during drought years (2021 - 2022). Yet I found little evidence of active SO42- processing in surveys conducted during drought years. SO42- remained the dominant form of sulfur (S) among all three basins (>95% of total S), implying little net change in the S pool. Similarly, dual stable isotope (34S and 18O) analysis showed limited isotopic enrichment among wetland basins, implying limited transformation of SO42- via microbial reduction. Sediment incubations confirmed the patterns observed with stable isotopes, showing little net removal of SO42- throughout the wetland. The preferential reduction of nitrate (NO3-) and other more energetically favourable constituents of the effluent may restrict the extent of microbial SO42- reduction throughout Frank Lake. The limited extent of emergent and submerged vegetation may also limit SO42- uptake by plants. Given the limited SO42- processing in Frank Lake, and the headwater position of this wetland complex in the broader aquatic network, my work provides context for previous reports of increasing salt concentrations documented in rivers of the South Saskatchewan River watershed.
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    Investigating the structure-function relationship of anti-mitotic natural products in Canadian prairie plants
    (Lethbridge, Alta. : University of Lethbridge, Dept. of Biological Sciences, 2024) Healy Knibb, Shannon M.; University of Lethbridge. Faculty of Arts and Science; Golsteyn, Roy
    This thesis investigates Canadian prairie plants as sources of natural product compounds capable of inhibiting human cell division. Natural products present an opportunity to identify novel anti-mitotic compounds to address the lack of known inhibitors for many mitotic regulatory proteins. By biology-guided fractionation, we purified the natural products anemonin from Pulsatilla nuttalliana and (+)-6-tuliposide A from Erythronium grandiflorum, and this is the first report of their anti-mitotic activities. We then conducted a comparative study between pulchelloid A (from Gaillardia aristata), anemonin and (+)-6-tuliposide A, and identified unique mitotic arrest profiles, suggesting distinct protein targets and mechanisms of action consistent with the widespread relationship between structure and function in biology. The discovery of natural product inhibitors from Canadian prairie plant species holds tremendous potential for advancing our understanding of mitotic regulation and contributes to the development of targeted treatments for precision medicine.
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    An exploration of family achievement guilt among Canadian university students
    (Lethbridge, Alta. : University of Lethbridge, Faculty of Education, 2023) Sanghera, Harleen; University of Lethbridge. Faculty of Education; Gunn, Thelma; Dixon, Sandra
    As an understudied topic with no peer-reviewed Canadian literature, family achievement guilt is the socioemotional experience related to having educational opportunities not afforded to one’s family members. In this study, 852 university students completed an online questionnaire that measured students’ family achievement guilt, maladaptive outcomes, empathic concern, and cultural congruence. First-generation students and racialized students were found to have higher levels of family achievement guilt compared to continuing-generation students and White students, respectively. Correlation analysis showed that family achievement guilt had a positive association with depression, anxiety, stress, and empathic concern. Moreover, a negative correlation was found between family achievement guilt and cultural congruence. Using thematic analysis, seven themes were created to capture the qualitative data from the short answer question. Overall, the emerging area of family achievement guilt research calls for the attention of researchers, post-secondary institutions, and mental health professionals to better support a diverse student body.
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    An examination of work-related stress and resilience in Canadian teachers
    (Lethbridge, Alta. : University of Lethbridge, Faculty of Education, 2023) Edge-Partington, Moriah; University of Lethbridge. Faculty of Education; Gunn, Thelma
    Teachers are susceptible to work-related stress, including burnout, secondary traumatic stress, and vicarious trauma. Yet, little is known about how resilience may serve as a protective factor and the prevalence of work-related stress in teachers. The aim of the current study was to examine work-related stress and resilience among K-12 Canadian teachers. Participants (N = 313) completed an online survey assessing work-related stress and resilience. Moderate to high work-related stress and significant associations with resilience were found among teachers. Significant differences were also found for teachers with low, intermediate, and high resilience. Furthermore, resilience significantly predicted lower work-related stress. These findings suggest resilience may serve as a protective factor. Analysis of short-answer responses highlight the challenges teachers are facing, and coping mechanisms for managing burnout and stress. These findings demonstrate a need for individual and systemic supports to help reduce vulnerability to work-related stress and promote resiliency in teachers.
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    The relationship between cost of equity and ESG: the effect of COVID-19
    (Lethbridge, Alta. : University of Lethbridge, Dhillon School of Business, 2024) Fan, Ruijie; University of Lethbridge. Dhillon School of Business; Tian, Gloria; Asem, Ebenezer
    Several prior studies report that environmental, social, and governance (ESG) initiatives temper the cost of equity. More recent studies show that COVID-19 increased the cost of equity. It is unclear whether the ESG mitigated the higher cost of capital during the COVID period. I focus on studying this using ESG and basic financial data for the period ranging from 2015 to 2022 based on U.S. and Canadian firms listed on NYSE, AMEX, and NASDAQ. The results show that the increase in the cost of equity during the COVID period concentrates less on firms with high ESG performance scores, suggesting ESG mitigated the increase in the cost of equity. This is consistent with the insurance-like effect of ESG on the cost of capital, cushioning the increase in the cost of capital during uncertain periods. In addition, my study reveals that the amplified ESG benefit in cost of equity reduction can be moderated by levels of industrial GDP growth and the stringency of the COVID-19 government policy.