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Evaluating Mine Water Resiliency in the Face of Climate Change
No full textAs the mining industry adapts to meet sustainability and environmental, social, and governance (ESG) goals in the face of climate change, water resiliency is one of the most critical issues. Ensuring adequate water management and treatment at a mine site is as critical as securing water for mining and processing operations. This is partly due to increasing water conflicts within a larger global water crisis, and also because stakeholders can increasingly revoke a mine’s social license to operate if it degrades local water quality or supply. Many current operating mines were built based on average conditions using deterministic water balance models and historic average data from the past century. The precipitation frequency data and statistics from historic records are no longer relevant, as new weather patterns forecast more periods of drought followed by extreme rainfall events of greater intensity than previously considered possible. One example of the significance of climate change is the drastic increase in the Federal Emergency Management Agency (FEMA) declared flood disasters in the United States (US). In 2000, there were only two flood disasters, but for the year through October 22, 2024, there were 66 flood disaster declarations in the US (Flavelle, 2024). Conversely, many operating mines in the southwestern US can expect to experience up to an 85% chance of a multi-decadal drought before 2100. Shrewd mine water managers, regulators, stakeholders, and consultants are adapting to this by developing stochastic water balance and water quality models that incorporate forward-looking climate change scenarios and anticipated changes in the mine site landscape to forecast possible, plausible, probable, and preferable impacts on both mine water quantity and quality management. The results often indicate water resiliency issues with adequate process water during periods of drought, deficiencies in stormwater management during heavy precipitation events, and deterioration in water quality that often requires additional treatment steps before discharge. The results from these models are then used to develop a more resilient and flexible water management plan that can adapt to and recover from any hydrological event. Updates to the water management plan may include adding or upgrading infrastructure, such as water collection ditches, retention ponds, and pumping stations, reprofiling existing landforms, adding a water treatment facility, and increasing surveillance of water levels, volume, and quality on site. This paper outlines recent methodologies for building forward-looking stochastic water balance and water quality forecast models that integrate climate change scenarios, water quality data, geochemical modelling results, and changes to the mine site over time that impact the water balance. Case studies and examples are also presented, showcasing how these models have been used to help mining companies develop more resilient water management plans and identify the work required to address these climate risks.Non UBCUnreviewedOthe
Chile : Solving Mine Water Production Without Major Capital Expenses
No full textThis work discusses the most recurrent problems and their causes in desalination plants in Chile, as well as their solutions. This is based on various consultancies where the design of the process, and operational data of the first years of operation, have been compared with the present. Among the main families of problems that prevent these plants from operating properly are: • Specific design requirements linked to the geographic location. • Staffing and training levels of operators and maintainers. • Outdated or missing operation manuals and maintenance plans. • Challenges with pretreatment processes. • Fluctuations in seawater quality at the intake. • Deviations related to demand that disrupt the operation. • Damage to pipes and units, primarily caused by corrosion or crystallization. The proposed solutions for these problems are evaluated to select those that must be addressed immediately and those that can be solved over time.Non UBCUnreviewedOthe
Evaluating Climate Change Impacts on Long-Duration Snowmelt Events and Mine Water Management
No full textMine water management systems in northern latitude and high-elevation areas must be designed to withstand floods caused by snowmelt events (snowmelt-only and rain-on-snow) in addition to rain-only events. The effects of climate change on these events, over both operational and post-closure timescales, are important to consider. Snowmelt events often govern hydrotechnical designs in Canada; however, estimating snowmelt in a changing climate is complex and lacks guidance. Underestimates of design floods present a considerable risk for mines; overestimates can result in significant costs and other unintended impacts. The impacts of climate change on short-duration (1-day) snowmelt events have been evaluated by the author for five case studies across Canada in a previous paper. Design events for conveyance structures are typically short-duration events. Longer duration events, with larger volumes, are critical for facilities that are designed to store and actively manage the inflow design floods (IDFs) or environmental design floods (EDFs). This paper describes the potential impacts of climate change on long-duration snowmelt events and impacts on mine water management for four case studies in British Columbia, Alberta, the Northwest Territories, and Ontario. This paper builds on previous work by the same author (Clark & Whitmore., 2024), which established a method for evaluating the impacts of climate change on snowmelt events. The method evaluates climate change impacts using a continuous simulation snowmelt model and downscaled Global Climate Model (GCM) data to quantitatively model the joint probabilities of snow cover, warm temperatures, and rainfall coinciding (and future changes to these probabilities). While the results of this paper are site-specific, the extended geographic range of the case studies can help inform mine owners on the potential range of impacts of climate change on long-duration snowmelt events and potential impacts on mine water management. Using a continuous simulation model helps reduce the uncertainty in quantifying the potential impacts and helps design resilient, future-proof facilities and systems.Non UBCUnreviewedOthe
The politics of public-private partnerships in global health governance : insights from the covid-19 response
No full textThe full abstract for this thesis is available in the body of the thesis, and will be available when the embargo expires.Arts, Faculty ofPolitical Science, Department ofGraduat
Electrospinning of high-asphaltene content carbon nanofibers and their application as supercapacitor electrodes
No full textCarbon nanofibers (CNFs) have gained significant attention for applications in composites, supercapacitors, and catalysis, but their commercial viability is limited by the high cost of traditional precursors like polyacrylonitrile (PAN). Asphaltene, a byproduct of petroleum refining, has been considered as an appealing precursor of CNFs due to its high carbon content and low cost.
This study explores the fabrication of CNFs from Alberta Oilsands Asphaltene (AOA) via electrospinning. In the first stage, this study aimed to identify viable routes for producing CNFs with as-received AOA. Based on previous studies, the effects of electrospinning parameters, polymer type, AOA/polymer ratio, dimethylformamide (DMF) and tetrahydrofuran (THF) solvent ratio, and solution concentration were systematically investigated. While PAN-AOA mixtures showed severe flocculation and poor spinnability, blends with polyethylene oxide (PEO) enabled successful fiber formation. Optimal conditions (concentration = 15 wt%, AOA: PEO = 9:1, DMF/THF = 1:1, 17 kV) yielded uniform electrospun nanofibers (ESNFs), but carbonization led to severe fiber fusion. Further thermogravimetric analysis (TGA) confirmed a loss of AOA content during electrospinning.
In the next stage, nitric acid treatment was applied to AOA, producing nitric-acid-treated AOA (NT-AOA). Characterization by elemental analysis (EA), Fourier transform infrared spectroscopy (FTIR ), and nuclear magnetic resonance (NMR) confirmed chemical modifications. The addition of sodium dodecyl sulfate (SDS) further enhanced ESNF morphology by reducing surface tension. The best results were achieved with ~27 wt% solution, NT-AOA: PEO = 95:5, and 2 wt% SDS, yielding bead-free ESNFs.
Carbonization produced CNFs with average diameters of ~172 nm, characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). Subsequent KOH activation resulted in activated CNFs (ACNFs) with a high surface area (984 m²/g) and enhanced porosity. Electrochemical testing showed a specific capacitance of 189 F/g and 84.8% retention after 5000 cycles, demonstrating the potential of NT-AOA-derived CNFs as low-cost, free-standing electrodes for supercapacitors.Applied Science, Faculty ofMaterials Engineering, Department ofGraduat
What about our bug? : a study on the responsiveness of package maintainers in the node package manager (npm) ecosystem
No full textThe Node Package Manager (npm) ecosystem is foundational to modern JavaScript development, enabling developers to rapidly build software by leveraging a vast array of third-party packages. However, this heavy reliance also introduces critical risks, particularly when bugs in upstream packages cascade down the dependency chain, affecting numerous downstream projects. This thesis investigates how maintainers of the 500 most depended-upon npm packages handle bug reports submitted by downstream developers. We adopt a mixed-methods approach to answer three research questions. First, we manually analyze 1,729 bug report issues to assess maintainer responsiveness and develop a taxonomy of reasons why certain bugs remain unresolved. Our manual classification reveals that while most upstream developers are responsive, some bugs remain unaddressed due to contributor practices, dependency boundaries, library-specific standards, and lack of engagement from upstream developers.
To scale the analysis, we evaluate the use of instruction-tuned Large Language Models (LLMs) in a zero-shot setting. Using a manually labeled ground truth dataset, we assess the effectiveness of LLMs in classifying issues as bug reports, determining maintainer responsiveness, and classifying unresolved bug reports. Our results show that LLMs can accurately replicate human classification, enabling large-scale analysis across 47,883 GitHub issues. The automated approach calculated a median per-package responsiveness ratio of 72%, further confirming that the majority of maintainers are actively addressing reported bugs.
Finally, we conduct a regression analysis to explore the relationship between maintainer responsiveness and package popularity, as measured by monthly downloads and GitHub stars. We find a positive correlation between responsiveness and downloads, suggesting that active maintenance supports widespread adoption. However, we observe a negative correlation with GitHub stars, indicating that visibility does not necessarily imply active bug handling.Science, Irving K. Barber Faculty of (Okanagan)Computer Science, Mathematics, Physics and Statistics, Department of (Okanagan)Graduat
Mad survivor, sad victim : the effect of labels and emotional expressions on perceived credibility of sexual assault allegations
No full textSexually assaulted individuals report experiencing a broad range of emotions in the aftermath of the event. However, common labels, like ‘victim’ or ‘survivor’, evoke stereotypes that do not capture this broad emotional experience. These stereotypes are consequential in that they dictate how an individual is expected to look/feel following a sexual assault. When emotional stereotypes are violated, individuals are perceived as less credible than those who conform to expectations. Specifically, victims expressing sadness are perceived as more credible than those expressing positive or neutral emotions. More recently, the term ‘survivor’ has been used as an alternative to ‘victim’. ‘Survivor’ has been associated with its own set of stereotypes; whereas victims are perceived as weak, survivors are expected to be strong and confident. However, less is known about the emotional stereotype content of the ‘survivor’ label and whether conforming to emotional stereotypes affects perceived credibility. The present study aimed to identify emotional expectations associated with sexual assault labels (Study 1) and whether emotions incongruent with label expectations impact perceived credibility (Study 2). In Study 1, a reverse correlation technique was implemented to provide visual estimates of mental representations of victim/survivors/persons who have experienced sexual assault. These images were rated on nine emotions to determine emotion-label pairs. Findings indicated that ‘victim’ faces were perceived as sadder than ‘survivors’ and ‘survivors’ were perceived as angrier than ‘victims.’ Faces of ‘persons who experienced sexual assault’ were found to be rated higher in anger compared to victims. In Study 2, participants viewed vignettes detailing a sexual assault encounter where the discloser was described as a survivor, victim, or person, expressing either sadness or anger, and provided credibility ratings. Study 2 results did not support the hypothesis that emotion-label congruent conditions would have greater credibility ratings compared to emotion-label incongruent conditions. These findings provide clarity to a growing body of research examining the role of stereotypes in judgements about sexual violence. Specifically, labels elicit instinct emotional stereotypes; however, they do not appear to interact with expressions of sadness or anger to affect perceived credibility.Arts and Social Sciences, Irving K. Barber Faculty of (Okanagan)Psychology, Department of (Okanagan)Graduat
Artificial Reproductive Technology Use and Family-Building Experiences of Female Adult Childhood Cancer Survivors : A Qualitative Study
No full textPurpose: Cancer treatments can result in subfertility or infertility in female adult childhood cancer survivors (ACCSs). While ACCSs may utilize assisted reproductive technology (ART) or other family-building options, the limited evidence describing their experiences remains a hindrance to developing and implementing appropriate patient-centered supports. The study’s aim is to describe the challenges female ACCSs experienced while navigating ART and family-building options, to inform improvements in clinical practice in a western Canadian province. Methods: In this qualitative Interpretive Description study, interviews were conducted with 15 female ACCSs and data were analyzed using an interpretive thematic approach and constant comparative techniques. Results: ACCSs’ narratives suggest they experienced five prominent challenges while navigating ART and family-building options, including (1) confronting unexpected, impaired fertility, (2) grieving loss and redefining identity, (3) encountering unsupportive healthcare, (4) exploring alternative paths of adoption and international family-building, and (5) facing financial strain. Conclusions: This exploratory study provides initial insights into the significant and multifaceted challenges female ACCSs experience related to family building and highlights gaps in healthcare services. Further research is warranted to articulate these challenges across contexts and the development and implementation of mitigating approaches. Implications for Cancer Survivors: The integration of comprehensive informational, psychosocial, and financial supports into existing cancer survivor and family-building services is vital to meeting female ACCSs’ unmet needs.Applied Science, Faculty ofMedicine, Faculty ofOther UBCNursing, School ofReviewedFacultyResearche
Sustainable Implementation Strategies for Market-Oriented Ecological Restoration: Insights from Chinese Forests
No full textMarket-oriented ecological restoration is vital for advancing ecological civilization and promoting harmonious human–nature relationships. However, the precise implementation pathway remains unclear. Few studies specifically address challenges that arise during ecological restoration implementation. Ensuring the smooth and effective implementation and landing of ecological restoration projects harmonizes ecological and economic objectives at the regional scale and fosters sustainable development in the region. Based on the policies of market-oriented ecological restoration collected from various Chinese provinces, and through multi-level institutional analysis, the policy measures are categorized into three phases: early, middle, and late. For each phase, we summarize the challenges encountered in implementing market-oriented ecological restoration projects. Finally, by the method of constructing theoretical models, we propose sustainable countermeasures based on multiple theoretical models. The results show (1) China’s ecological restoration sector is experiencing rapid growth, and market-oriented policies in China, multiple Chinese provinces, and municipalities have enacted successive market-oriented ecological restoration policies, and the outlook for ecological restoration marketization in China remains highly promising. (2) The implementation process of current market-oriented ecological restoration projects confronts and encounters several challenges. These include the absence of project screening and evaluation mechanisms, limited investment and financing channels, ill-defined approval processes, ambiguous delineation of departmental responsibilities, insufficient industry incentives, and the absence of effective operational and management mechanisms. (3) To address the identified challenges, taking forest ecological restoration as an example, theoretical models should be developed encompassing six critical dimensions: the aspects of the mechanism, mode, approval process, management system, industrial chain, and platform. This aims to provide sustainable pathways for the effective implementation of market-oriented forest ecological restoration projects.Forestry, Faculty ofNon UBCReviewedResearcherPostdoctora
The Primary Role of Noncoding RNA in the Pathogenesis of Cancer
No full textThe discovery of oncogenes and tumor suppressor genes provided important insights into the molecular pathogenesis of cancer but also revealed some contradictions in the prevailing somatic mutation theory. The evidence that noncoding RNAs (ncRNAs) form an elaborate network that regulates the flow of genetic information in eukaryotic cells offers an explanation for the inconsistencies. ncRNAs comprise a wide variety of molecules that interact with one another as well as with other RNAs, DNA, and proteins, over whose activities they exert a regulatory influence. The outcome of the dynamic interactions of the cell’s biomolecules is the emergence of higher-order states of equilibrium, called attractor states, which correspond to the gene-expression configurations of distinct cell types. Attractor states are relatively stable systems, but they are susceptible to perturbation by a disturbing force, such as mutation. Mutations that disrupt the ncRNA network can enable the cell to undergo a state transition towards a potentially neoplastic one. This is the crux of tumorigenesis. An inquiry into the architecture of the ncRNA network and its role in tumorigenesis is required to complement our knowledge of the well-known cancer genes as well as serve as a guide in the design of new anticancer therapeutics.Medicine, Faculty ofMedicine, Department ofReviewedFacult