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Advancing functionality of soft actuators through selective stiffness modulation and smart materials
No full textThe full abstract for this thesis is available in the body of the thesis, and will be available when the embargo expires.Applied Science, Faculty ofMechanical Engineering, Department ofGraduat
Identifying anger in digital spaces
No full textThis thesis examines expressions and interpretations of anger in computer-mediated-communication (CMC) and identifies specific tactics and important factors in this expression and interpretation. This research is based on online data collection and subsequent online survey.
The data collection portion of the research consisted of gathering samples of expressions of anger from social media platforms Reddit, YouTube, and TikTok. The samples were all gathered from discussions regarding the Canadian Housing Crisis. These samples were categorized and co-validated into different types of anger, and then analyzed for trends in specific textisms (linguistic features characteristic of CMC). Patterns in linguistic features found from this process were then used to create an online survey. The survey provided more detailed information for how CMC users interpret and express anger and yielded a total of 90 responses. The survey consisted of four major sections: data validation, where participants were asked to categorize samples from the previous data collection, roleplay, where participants were asked to type out what the angry message would be sent in response to a specific prompt, ranking, where participants ranked the emotional expression of a message with varying textisms, and analysis, where participants were provided texts asked to identify why this would be interpreted as angry or not.
The data collection and survey both found that specific features, specifically using a period for the final sentence in a message and quotation marks, are the features that are most interpreted as indicating anger. However, the features of expressions of anger across both the data collection and the survey also included questions, but this did not affect the interpretation of anger. This research finds that the most critical feature to interpreting and expressing anger is context. Overall, this thesis discusses the ways that CMC users interpret and express anger and the ways in which gender interact with this expression and interpretation, as well as highlights the large role context plays in interpretation of anger in CMC.Arts and Social Sciences, Irving K. Barber Faculty of (Okanagan)Graduat
Comparing monocyte and skeletal muscle mitochondrial metabolism in individuals that are lean or living with obesity - a cross-sectional study
No full textObesity is a major risk factor for type 2 diabetes (T2D), in part due to its association with chronic low-grade inflammation and insulin resistance. Monocytes represent an important immune cell subset implicated in obesity-related inflammation. Evidence suggests that monocyte phenotype is related to their metabolic profile, however monocyte metabolism in obesity remains poorly characterized. Second, mitochondrial dysfunction is commonly exhibited during obesity and type 2 diabetes, however, these studies often do not account for activity levels, which have been shown to greatly impact mitochondrial function. Therefore, this study aimed to compare mitochondrial respiration in circulating monocytes and vastus lateralis skeletal muscle between lean individuals and those living with obesity, while matching participants for habitual activity levels.
In a cross-sectional study design, 37 healthy adults (lean: n=20; obesity: n=17) - matched for physical activity, age, and sex distribution - completed two experimental visits involving a skeletal muscle biopsy, serial blood sampling throughout a mixed meal tolerance test (MMTT), and accelerometer-based physical activity tracking. Mitochondrial respiration was assessed using high-resolution respirometry in monocytes isolated from fasted blood samples and in permeabilized skeletal muscle fibers from the vastus lateralis biopsy.
We found that monocyte respiration was significantly higher in lean individuals for CI+II oxidative phosphorylation (OXPHOS) and maximal uncoupled respiration (p < 0.05), suggesting diminished respiratory capacity in monocytes from individuals with obesity. Opposingly we found that skeletal muscle respiration was significantly higher in the group living with obesity across all respiratory states (p < 0.05). Activity levels were similar between groups, suggesting results were not confounded by habitual physical activity.
These findings highlight distinct, tissue-specific alterations in mitochondrial metabolism in young individuals with obesity compared to lean counterparts. We hypothesize that the reduction in monocyte respiration may reflect systemic impairments in mitochondrial function, while increased skeletal muscle respiration may represent an early compensatory mechanism to energy surplus and lipid oversupply.Health and Social Development, Faculty of (Okanagan)Health and Exercise Sciences, School of (Okanagan)Graduat
Paramedicine and intimate partner violence : investigation of an underutilized resource with potential to help address a public health pandemic
No full textThe full abstract for this thesis is available in the body of the thesis, and will be available when the embargo expires.Health and Social Development, Faculty of (Okanagan)Health and Exercise Sciences, School of (Okanagan)Graduat
Dissecting the cell of origin and progression events of DICER1 syndrome-associated sarcoma
No full textThe full abstract for this thesis is available in the body of the thesis, and will be available when the embargo expires.Medicine, Department ofPathology and Laboratory Medicine, Department ofGraduat
Role of transient pore pressures and effective stresses in progressive open pit slope failure
No full textThis dissertation investigates the role of transient pore pressures in the progressive failure of large open pit mine slopes. Conventional slope stability analyses often assume constant rock mass strength and rely on predefined failure surfaces and discrete triggering events. However, empirical evidence from over 360 detailed case studies of failures suggests that many mid-slope, multi-bench failures occur without a clear trigger, long after excavation. These patterns point to an alternative failure mechanism driven by the accumulation of damage under cyclic, recharge-induced changes in pore pressure.
To evaluate this hypothesis, the research integrates four lines of investigation. First, an empirical analysis of 364 large open pit failures was conducted, classifying cases by hydrogeological conditions and failure timing. Second, a site-specific case study involving a 2011 pit failure in British Columbia was developed using detailed displacement, piezometric, and structural data. Third, calibrated continuum and discontinuum numerical models were constructed to simulate the hydromechanical response of slopes subjected to seasonal recharge. A one-way coupled approach was used to impose transient pore pressures from analogue groundwater models into mechanical simulations. Finally, a risk framework was developed to support the practical assessment of transient pore pressure effects in operational and post-closure settings.
The results show that transient pore pressure increases can significantly reduce effective stresses, promoting localized slip and strain weakening, and accelerating failure even in slopes with no persistent structural predisposition. Key mechanisms include distance–dilatancy lag, stress-path–dependent degradation, and step-path rupture propagation. The classification framework based on the Modified Stability Number (N*) and RMR76 offers forecasting capability for identifying potential failure regimes. Post-mine closure scenarios are shown to carry residual risk due to groundwater rebound and pre-damaged slopes.
This research advances a mechanism-based understanding of slope failure and provides practical tools for prediction, monitoring, and risk management across the mine life cycle.Science, Faculty ofEarth, Ocean and Atmospheric Sciences, Department ofGraduat
Towards improved ultrasound-based methods for prostate cancer detection
No full textThe full abstract for this thesis is available in the body of the thesis, and will be available when the embargo expires.Applied Science, Faculty ofBiomedical Engineering, School ofGraduat
The DNA2 nuclease as an ALTernative target in cancer
No full textThe full abstract for this thesis is available in the body of the thesis, and will be available when the embargo expires.Medicine, Faculty ofGraduat
The equivalence and relative efficacy of psychodynamic psychotherapy and cognitive behavioural therapy for the treatment of adult depressive disorders : a meta-analytic test of active comparison randomized controlled trials
No full textMeta-analyses comparing psychodynamic psychotherapy and cognitive-behavioural therapy (CBT) for depressive disorders are limited by heterogeneity in diagnostic samples, comparators, and a lack of equivalence testing. Additionally, extant meta-analyses on psychodynamic psychotherapy and CBT focus on standardized mean differences (SMDs) without examining potential differences in response rates, reliable change, deterioration, and acceptability (i.e., all-cause dropout). Objective: This dissertation addresses these gaps through a meta-analytic test of the equivalence and relative efficacy of psychodynamic psychotherapy and CBT for depressive disorders in the adult general population. Method: A comprehensive literature search across multiple databases using reliable screening methods identified nine active comparison randomized controlled trials (RCTs) directly comparing manualized psychodynamic psychotherapy (N = 572) and CBT (N = 509) for diagnosed depressive disorders in adults. Weighted pooled SMDs (Hedges’ g) were computed, and equivalence testing (g = 0.24) was conducted at post-treatment and follow-up using the two one-sided test procedure. Response rate (i.e., ≥ 50% symptom reduction), reliable change, deterioration, and acceptability were analyzed as event rates and relative risk ratios (RR). For studies that did not report response, reliable change, or deterioration, these values were estimated using a validated imputation method. Results: Independent raters determined that all included studies were of adequate quality. At post-treatment, depressive symptoms were statistically equivalent across psychodynamic psychotherapy and cognitive behavioural therapy (k = 9; g = -0.11, pequivalence = .048, pNHST = .212). At follow-up, the longest time point within a year, depressive symptoms were neither statistically equivalent nor statistically different (k = 6; g = -0.16, pequivalence = .184, pNHST = .126). Rates of response rates, reliable improvement, deterioration, and acceptability did not differ significantly across psychodynamic psychotherapy and CBT. Conclusion: Manualized psychodynamic psychotherapy and CBT demonstrate equivalent efficacy at post-treatment for depressive disorders in adults. However, insufficient data exists to determine equivalence at follow-up. There was no evidence that psychodynamic psychotherapy and CBT differ significantly in rates of response, reliable improvement, deterioration, or acceptability. Likewise, the observed differences between psychodynamic psychotherapy and CBT for reducing symptoms of depression are modest. Accordingly, patient preference should guide treatment selection.Arts, Faculty ofPsychology, Department ofGraduat
Estimating and explaining below-ground carbon storage in British Columbia tidal marshes
No full textFound in the coastal intertidal transition zone between the land and ocean throughout global temperate coastlines, tidal marshes absorb and assimilate carbon dioxide at a rate equal to or higher than the most productive ecosystems on Earth. The inherent ecological processes that create and sustain tidal marshes are also responsible for its carbon storage ability. In addition to high primary production, marsh vegetation traps suspended sediments brought in by ocean tides and terrestrial rivers, accreting organic matter vertically in a highly dynamic process. Despite growing mapping and sampling efforts globally, it is unclear how much the carbon storage capacity of tidal marshes varies with environmental influences, and marshes on the coast of British Columbia (BC) have received less attention in existing studies and data. Here, I collate and synthesize belowground measurements of soil organic carbon (SOC) stocks (Mg C per ha) from soil cores collected across BC tidal marshes. I estimate that BC’s tidal marshes contain 4.7-7.3 Tg of C in shallow SOC stocks (30 cm), and 11.1-17.2 Tg of C in deep SOC stocks (100 cm). I find that SOC stocks in BC’s tidal marshes are consistent with other North American and Pacific coast marshes. My analysis quantifies variation in belowground measurements with environmental factors, applying novel metrics designed to describe imported carbon burial processes, in addition to conditions of marsh zonation, vegetation, ocean, and topography. I find that SOC stocks in BC’s tidal marshes were greater in the high marsh zone, increased with latitude, maximum NDVI (above-ground biomass), and distance from the low water line (LWL), while higher fetch (wind and wave exposure), slope, and distance from a major river outlet, generally produced lower SOC stocks. My study sheds light on the importance of analyzing ecologically informed covariates, including stability of the marsh and terrestrial inputs of organic carbon in tidal marshes. While improving the understanding of drivers of variation behind belowground marsh carbon storage, my study also reveals important data gaps in Pacific tidal marshes, particularly concerning soil depth and extent. This data-synthesis approach can inform strategies to enhance SOC storage through targeted management, restoration, and conservation.Arts, Faculty ofGeography, Department ofGraduat