Mechanical and structural behaviour of rubberised recycled aggregate concrete

This research examined the impact of using recycled coarse aggregate (RCA), crumb rubber (CR), and polypropylene fibre (PPF) as partial replacements for traditional concrete coarse and fine aggregates. Through a series of experiments, the study assessed the compressive strength, tensile strength, and flexural response of recycled aggregate concrete with CR and PPF in comparison to natural aggregate concrete. Further tests examined the bond strength of concrete with steel reinforcement, aiming to optimise resource use, and investigated the shear behaviour of concrete beams containing RCA, CR, and PPF. The findings contributed insights into the potential of these recycled materials to create more sustainable concrete solutions. The study found that increasing crumb rubber (CR) content resulted in reduced compressive, tensile, and flexural strength while adding polypropylene fibre (PPF) improved these properties. For toughness and ductility, PPF had the most significant positive effect, with both RCA and CR enhancing these aspects when added incrementally. In bond analysis, combining CR and PPF reduced concrete’s bond with steel reinforcement, though using either material alone in certain RCA mixtures improved bond strength. Shear strength tests showed that CR reduced shear strength, post-diagonal cracking resistance, toughness, and deformability in concrete beams, but adding PPF enhanced these effects at up to 30% RCA replacement. The optimal composition (30% RCA, 5% CR, and 1% PPF) showed the best shear resistance, deformability, and toughness, with minor rubber additions (up to 5%) enhancing beam deformability and fibre increasing post-crack resistance. The research concluded that the optimal mix for sustainable concrete applications of recycled materials includes up to 30% recycled coarse aggregate (RCA), 5% crumb rubber (CR), and up to 2% polypropylene fibre (PPF). This combination demonstrated the best balance of mechanical and structural performance, making it a viable option for integrating recycled materials into concrete in future.Applied Science, Faculty ofEngineering, School of (Okanagan)Graduat

Neck muscle and intervertebral dynamics during impending headfirst impacts in rollover crashes

Catastrophic spine and spinal cord injuries remain a public health concern. The largest share of these injuries is attributed to motor vehicle crashes, e.g., headfirst impacts in vehicle rollovers, and this share has remained stable, despite advancements in vehicle safety. To improve our understanding of the underlying injury mechanisms, this dissertation comprised an epidemiological study, two in vivo experiments, and the design of a novel rollover test device for future human subject experiments. In the epidemiology study, we examined how different types of cervical spine injuries vary with different occupant-related factors, and compared rollovers to non-rollovers. We found that all types of cervical spine injuries were 3.4–6.5 times more likely to occur in rollovers compared to non-rollovers, and the frequent occurrence of vertebral fractures suggests that countermeasures focused on preventing fractures will effectively prevent most cervical spinal cord injuries. In our first in vivo experiment, we exposed eleven human subjects to headfirst freefalls that simulated an impending headfirst impact. We quantified head and cervical spine posture before and at the end of the freefalls, and head kinematics and muscle activation during the freefalls. We confirmed our hypothesis that a 312.5 ms freefall is sufficiently long for an individual to significantly change their head-neck posture and muscle activation states prior to an impending headfirst impact. Subjects consistently moved their necks anteriorly and inferiorly, increased their neck’s anterior eccentricity, and rotated their cervical spines and heads in the flexion direction. Subjects used a variety of muscle activation patterns to achieve this consistent head and neck rotation response, and muscles were activated well before the end of the freefall duration. Finally, to increase fidelity to a real-world rollover, we designed and tested a novel rollover test device that simulates the yaw, trip and first half roll of a vehicle rollover with a high repeatability, that is safe for human subject use, and that enables the collection of human subject kinematic and muscle activation data throughout the rollover. The findings of these studies will improve our understanding of cervical spine injury mechanisms, and represent an incremental step towards their prevention.Applied Science, Faculty ofMechanical Engineering, Department ofGraduat

To be a shameful/shameless scholar : the decline of Confucian moral authenticity in The Scholars

This thesis draws attention to the references to shame in The Scholars (Rulin waishi; originally published in 1749). As categorized by Olwen Bedford and Kwang-kuo Kwang, there are broadly “four types of shame (diu lian, can kui, xiu kui and xiu chi)” in Chinese culture. While characters in The Scholars are shameful when they lose their external reputation or face, they are ultimately shameless about their internal moral selves. The thesis investigates the Confucian moral expectation to be shame-conscious and sheds light on the inconsistency between the characters’ external expressions of shame and internal shamelessness. How does the author, Wu Jingzi (1701 – 1754), construct a narrative world that underscores a lack of shame within individuals in their ways of pursuing rank and wealth (gongming fugui)? The thesis illustrates how authentic and inauthentic expressions of shame draw attention to the perceived decline of Confucian moral virtue in eighteenth-century China. The genre of satire exposes how gongming fugui seekers’ feelings of shame are concerned with their reputational damage rather than their deviation from Confucian moral standards. By highlighting the different contexts in which diu lian, can kui, xiu kui and xiu chi appear in The Scholars, this thesis argues that shame and shamelessness are satirically presented through seekers of gongming fugui and examination success who fail to cultivate authentic Confucian moral virtues in Wu Jingzi’s novel.Arts, Faculty ofAsian Studies, Department ofGraduat

Monitoring and Discrimination of Salt Stress in Salix matsudana × alba Using Vis/NIR-HSI Technology

(1) Background: Salt stress poses a significant challenge to plant productivity, particularly in forestry and agriculture. This research explored the physiological adaptations of Salix matsudana × alba to varying salt stress levels and assessed the utility of hyperspectral imaging (HSI) integrated with machine learning for stress detection; (2) Methods: Physiological metrics, such as photosynthesis, chlorophyll concentration, antioxidant enzyme activity, proline levels, membrane stability, and malondialdehyde (MDA) accumulation, were analyzed under controlled experimental conditions. Spectral data in the visible (Vis) and near-infrared (NIR) ranges were acquired, with preprocessing techniques enhancing data precision. The study established quantitative detection models for physiological indicators and developed a salt stress monitoring model; (3) Results: Photosynthetic efficiency and chlorophyll synthesis while elevating oxidative damage indicators, including enzyme activity, proline content, and membrane permeability. Strong correlations between spectral signatures and physiological changes highlighted HSI’s effectiveness for early stress detection. Among the machine learning models, the Convolutional Neural Network (CNN) trained on Vis+NIR data with standard normal variate (SNV) preprocessing achieved 100% classification accuracy; (4) Conclusions: The results demonstrated that HSI, coupled with modeling techniques, is a powerful non-invasive tool for real-time monitoring of salt stress, providing valuable insights for early intervention and contributing to sustainable agricultural and forestry practices.Forestry, Faculty ofNon UBCReviewedFacultyResearche

Decolonizing My Mind, Indigenizing My Practice : A Self-Study

Canada is opening its eyes and mind to its colonial past and with that, Canadian Home Economists are working towards decolonizing the field. This paper examines both decolonization and Indigenization through the lens of a Canadian Food Studies teacher. It explores the theoretical and practical methods to decolonize and Indigenize the classroom using Indigenous pedagogies. Using qualitative methods such as narrative inquiry and action research, the author examines her current practices to reveal methods already in use that align with Indigenous principles, and then conducts two action research cycles to determine how these strategies improve her practice.Education, Faculty ofCurriculum and Pedagogy (EDCP), Department ofUnreviewedGraduat

Repentance as tragic virtue : structure, genre, and theme in the Greek Life of Adam and Eve

The Greek Life of Adam and Eve (GLAE), a narrative about the last days of Adam and Eve composed in the early centuries CE, has received increasing scholarly attention in recent years, including the publication of a critical edition and a commentary. There are several literary studies of the narrative, but no satisfactory account of its governing principles. This essay takes a structural approach to elucidate the GLAE’s narrative progression, genre, and theme. Narrative cohesiveness can be apprehended when the relationship between God and humans is centred. This view is possible through perceiving God in the GLAE as a humanlike agent inasmuch as God is amenable to social intercourse. The narrative is oriented around God’s wrath and the human quest for mercy, with a prayer of repentance uttered by Eve as the tipping point that introduces God’s mercy on Adam, posthumously. Eve’s prayer fits into a pattern of repentance as a form of supplication for mercy that is widespread cross-culturally, appearing in both pagan Greek and biblical precursors, as well as other early Jewish literature. Study of genre draws on theoretical work on the radial prototype-centred organization of categories to show that the GLAE tells its story in the style of Greek tragedy, in features such as telling a narrative of a legendary figure, through dialogue, with emphasis on suffering, within a scenario of endangerment. The GLAE occasionally deviates from the tragic style it establishes in order to depict God as unique: a High God in charge of fate, who never appears on the tragic stage, but who is nevertheless accessible to tragic narrative through Jewish epiphanic conventions. Repentance in the form of Eve’s prayer is a uniquely Jewish virtue that makes possible access to and reconciliation with God. In this fashion, the GLAE uses Greek conventions to promote and make comprehensible Jewish views on God, and on repentance as a virtuous way to relate to God, in a Greek cultural context.Arts, Faculty ofAncient Mediterranean and Near Eastern Studies, Department ofGraduat

Point of care ultrasound in rural British Columbia : an investigation of quality and effect on clinical decision making

Introduction: Point of care ultrasound (PoCUS), an exam performed and usually interpreted at the bedside, has the potential to improve the quality of rural healthcare and make rural practice more sustainable for physicians. Yet, there are few clinical studies on the usefulness and quality of this tool in rural communities. This study aimed to understand the effect of PoCUS on rural GPs’ diagnostic certainty and clinical decision making, and the accuracy of their exams. Methods: Rural GPs in the Canadian province of British Columbia (BC) collected prospective pre/post PoCUS survey data on their diagnostic probability (0-100% continuous scale) for a main working diagnosis and their patient management plan. The Wilcoxon signed rank test for clustered data was used to assess the statistical significance of observed changes from pre to post PoCUS in diagnostic certainty (an ordinal scale ascertained from diagnostic probability) and the highest level of care included in a patient management plan. Rural GPs also shared images from their PoCUS scans. For each scan, two physician specialists, considered imaging experts for the study, independently interpreted images. GP interpretation was compared to the interpretation of experts. Results: Five GPs, each from a different rural community in BC, collected data on 68 PoCUS exams over two to 10 weeks in 2022-23. Diagnostic certainty increased for 68% of scans (p-value=0.01). The highest level of care in a patient management plan changed for 36% of scans (p-value=0.08); it decreased for 32% and increased for 4%. Seven imaging experts reviewed images for 55 scans. There was inadequate power to precisely assess PoCUS accuracy due to expert reviewers having differing interpretations of images or agreeing that the images provided were inadequate. Discussion: With our study, we have taken an initial step within the field of clinical PoCUS research in rural Canada. We have generated evidence on the usefulness of PoCUS for rural GPs, which should be validated by larger studies. Our methodological recommendations based on lessons learned during secondary image review can help other researchers design rigorous PoCUS quality studies that yield adequate sample sizes.Medicine, Faculty ofPopulation and Public Health (SPPH), School ofGraduat

High-resolution dynamical downscaling to explore climate- and terrain-influenced changes to the weather of British Columbia

The province of British Columbia (BC) is experiencing changes to its climate and terrain that may impact its weather, and therefore the lives of its residents and health of its ecosystems. I used the Weather Research and Forecasting (WRF) model to simulate climate-influenced changes to the weather of BC in 2021 by: (1) exploring and verifying different model configurations for dynamical downscaling, and (2) using the pseudoglobal warming (PGW) approach to perturb the input boundary conditions under different climate regimes. I explored perturbations for two warmer (future) climate regimes, and a cooler (pre-industrial) regime. Results include changes to the monthly means of temperature and precipitation in BC, as well as to the extreme June 2021 heat-wave and November 2021 atmospheric-river events. From a terrain-modification standpoint, the Elk Valley region in southeastern BC is an area of active open pit coal mining, resulting in the demolition of mountains and infilling of quarries. This led to changes in local circulations that impacted nearby ecosystems. To simulate these changes, I ran WRF at a sub-kilometre grid spacing over the Elk Valley, with current and modified terrain to simulate and quantify changes to the weather. It was found that terrain changes can have impacts on the weather much further afield than in the immediate vicinity of the mines. From all of these simulations, I was able to demonstrate the utility of high-resolution modelling to study the dynamical effects of modified climate and terrain on weather. I was also able to quantify these effects using standard weather verification metrics as well as more holistic image-comparison metrics such as the mean structural similarity index metric (MSSIM) and the radially averaged power spectral density (RAPSD). The model output of high-resolution gridded datasets tailored for BC are developed to aid future decision-making and environmental assessments.Science, Faculty ofEarth, Ocean and Atmospheric Sciences, Department ofGraduat

Fire-vegetation feedbacks in a Southeast Asian forest-savanna mosaic

Fire-vegetation feedbacks are critical to the dynamics of forest-savanna mosaics. Differences in fire potential between savanna (high fire potential) and forest (low fire potential) drive distinct fire regimes that enable their coexistence as landscape mosaics. In Southeast Asia, forest-savanna mosaics are vital for regional biodiversity, natural resources, and ecosystem services, yet they remain poorly documented and are increasingly threatened by degradation and homogenization. To better understand fire dynamics across Southeast Asian forest-savanna mosaics, we collected data on fuels, microclimate, and canopy cover within a mosaic in northern Cambodia. Data were gathered during both the early and late dry seasons from 46 sites representing a range of canopy cover, fuel conditions, and times since fire. These data were then used to parameterize BehavePlus6 fire behavior prediction software to model fire potential across the mosaic and over the season. Canopy cover moderated fire potential in two key ways: (1) the probability of ignition decreased gradually along the canopy cover gradient, and (2) the rate of spread, fireline intensity, and flame length declined sharply, reaching a fire-suppression threshold at approximately 2.2 LAI. This threshold coincided with grass exclusion, underscoring the central role of grass biomass in shaping fire dynamics within these systems. Between 1.2 LAI and 2.2 LAI, grass loads were highly variable, indicating a large influence of site-specific factors, other than canopy cover, in determining fire within this range. Fire potential increased from the early to the late dry season, driven primarily by leaf litter accumulation—a finding that contrasts with patterns observed in other mesic savannas and emphasizes the high tree cover and deciduousness of Southeast Asian savannas. Fuel moisture also contributed to intraseasonal variation in fire potential. We recommend against indiscriminate fire suppression policies, which risk promoting high-severity fires or facilitating forest encroachment, both of which threaten mosaic stability and heterogeneity. Adaptive management strategies that consider local dynamics and the ecological role of fire are essential for maintaining the resilience and diversity of SE Asian forest-savanna mosaics.Arts, Faculty ofGeography, Department ofGraduat

Cinematic influence : the significance of Indian cinema on TikTok and in South Asian women's diasporic identity

This thesis investigates how TikTok serves as an imaginative space for South Asian women in diaspora to deepen their self-identity, through the consumption of Indian cinema on the platform. I argue that through community spaces that are created on TikTok, South Asian women are able to produce a sense of self, and combat white feminist influences they may have encountered in Western colonial environments. This project centers three films in Indian cinema: Diwale Dulhania Le Jayenge (1995), Kabhi Khushi Kabhi Gham (2001), and Devdas (2003), and focuses on nine TikToks that were inspired by content curated on my own TikTok feed. I chose these pieces as they are indicative of the films’ fandom and illustrate the role Indian cinema has played for South Asian women in identity formation. This project situates itself in feminist, race, and diasporic studies, and is greatly inspired by the work of Arjun Appadurai, Avtar Brah, bell hooks, and Rafia Zakaria. I employ multimodal discourse analysis throughout this thesis to showcase the layers of media involved when examining a TikTok post, I delve into the meaning behind social media interactions, including the implications of liking, saving, posting, commenting, and sharing. In addition, I utilize this method when investigating the significance of scenes, characters, plot lines, cinematography, and songs in the films being studied. I provide an examination of why the messages in Indian cinema, such as women being complex and dynamic, are significant and differ from representations of South Asian women in Western media. As well, I concentrate on depictions of South Asian men and how Indian cinema allows South Asian women to understand themselves and their sexual desires. I then consider how Indian cinema fandom and content creators develop communities of care, and how user communication on TikTok is indicative of feminist acts themselves.Arts, Faculty ofGender, Race, Sexuality and Social Justice, Institute forGraduat