Theses, Dissertations, and other Required Graduate Degree Essays

Bedrock rivers largely set the pace for landscape evolution in unglaciated terrain and yet little is known about what controls their morphologies. I examine the role that geologic structure plays in the alignment and morphology of bedrock canyons at different scales. At the watershed scale, I examine the striking alignment of the Fraser River with the Fraser River Fault zone and its largely unmapped secondary fault structures. I explore how large sediment inputs affect bedrock canyons alignment and their morphological characteristics. At the reach scale, I investigate how geological structure influences bedrock canyon width. I find that width constrictions coincide with dominant sub-horizontal joint sets whereas widenings coincide with dominant sub-vertical joint sets. I consider this in the context of sequential constrictions and widenings and propose a conceptual model where sub-vertical jointing makes canyon walls more susceptible to failure due to river undercutting than horizontal jointing.

The researcher surveyed 97 British Columbia ADST or STEM educators concerning their understandings and perceptions of maker-centred pedagogies, and their willingness to apply these approaches. Questions addressed current applications of maker-centred pedagogies in public schools, and the major factors that affect the implementation of maker-centred approaches, including the characteristics of maker-centred pedagogies, the tools and resources used in making activities, and the strategies that support maker-centred approaches. Findings from qualitative and quantitative analyses suggest that most respondents favored maker-centered pedagogies, and that maker-centred pedagogies are being implemented most often in secondary STEM classrooms, though least in Mathematics. Teachers report using both high-tech digital tools and low-tech and traditional tools in making activities. Concerns raised by respondents, but rarely mentioned in literature on making, are student safety, having sufficient physical space for making, fostering appropriate attitudes toward making, and a need for additional teacher training in this area.

Reflections in videos are obstructions that often occur when videos are taken behind reflective surfaces like glass. These reflections reduce the quality of such videos, lead to information loss and degrade the accuracy of many computer vision algorithms. A video containing reflections is a combination of background and reflection layers. Thus, reflection removal is equivalent to decomposing the video into two layers. This problem is ill-posed as there is an infinite number of valid decompositions. To address this problem, we propose a user-assisted approach for video reflection removal. We rely on both spatial and temporal information and utilize sparse user hints to help improve separation. The key idea of the proposed method is to use motion cues to separate the background layer from the reflection layer with minimal user assistance. We show that user-assistance significantly improves the layer separation results. We implement and validate the proposed method through quantitative and qualitative results on real and synthetic videos. Our experiments show that the proposed method successfully removes reflection from video sequences, does not introduce visual distortions, and significantly outperforms the state-of-the-art reflection removal methods in the literature.

Wildland fires around the globe have been increasing in their severity and frequency, leaving natural and heritage resource managers to cope with their irreversible effects. Here, I review the literature on wildland fire environments and behavior and I investigate their influence on buried archaeological materials. To better understand this process, I propose and test a protocol which utilizes soil micromorphology and Fourier transform infrared microspectroscopy to quantify the impact of thermal energy on the sub-surface environment and the transformations that occur within the chemistry and mineralogy of common organic soils. An initial application of this protocol was carried out within the perimeter of a wildland fire near Logan Lake, British Columbia, which successfully measured on a millimetre-scale the heat diffusion pattern through the soil column. This analytical protocol can now be used in post-burn investigations to assess the effects of wildland fires on sub-surface archaeological materials of different regions.

Overgrazing and soil erosion are widespread and chronic environmental problems in the Icelandic highlands. Restoration efforts have included the application of fertilisers and grazing exclusion to increase plant biomass and reduce bare ground, but the effects of fertilisers on plant community composition across ecological conditions remain unresolved. I measured the combined effects of grazing exclusion and fertilisation, including factorial applications of nitrogen (N), phosphorus (P) and potassium (K), in both vegetated and degraded areas at sites with contrasting soil conditions. After four years I found 1) above-ground biomass induced by fertiliser was counteracted by sheep grazing, and 2) joint application of fertiliser and grazing exclusion had contrasting effects on species diversity in vegetated habitats where NPK applications and grazing exclusion reduced species diversity, than in degraded habitats where NPK applications increased species diversity irrespective of grazing. These results contribute to improving restoration efforts in high latitude tundra rangelands.

Large-scale sequencing projects and sequencing of patient samples can reveal mutations or polymorphisms in many genes, but the functional consequences are not always apparent especially for single amino acid substitutions. My research project focussed on addressing the discrepancy between the amount of sequenced gene variants and the knowledge about their functionality in development and disease. We developed Drosophila genetic assays for rapid, inexpensive functionalization of human PTEN variants with unknown significance (VUS) in order to learn if individual mutations play a role in development of disease. We assayed the ability of PTEN variants to suppress phenotypes observed when the oncogenic phosphoinositide 3-kinase (PI3K) signalling pathway is activated in the developing Drosophila wing. Our assay was validated with a few previously studied variants followed by characterizing 100+ human PTEN VUS. Ultimately, knowing which PTEN variants are non-functional or functional is crucial for targeted therapeutic and personalized treatment of PI3K-dependent diseases and cancers.

Momentum is building behind a new approach to Crown-Indigenous relations that is based on reconciliation, shared decision-making, and nation-to-nation engagement. In British Columbia’s Nicola watershed, this shift has manifested itself in the Nicola Watershed Governance Project (NWGP), an innovative pilot project that is seeking to establish watershed co-governance between the provincial government and five Indigenous Nations. A major challenge facing the NWGP is securing sustainable funding that will ensure the long-term viability of the project beyond the three-year pilot funding period. This research addresses this challenge by investigating key considerations and potential options for developing a sustainable funding model for the NWGP. Three main research methods were employed: (1) background research to identify key funding concepts and situate the NWGP in broader historical and theoretical context; (2) a jurisdictional scan to identify key learnings from other funding models; and (3) a structured analysis of potential core funding options for the NWGP. While investigating sustainable funding for the NWGP was the primary objective of this research, the results are also analyzed to draw conclusions regarding the state of watershed governance funding across the province.

On May 14, 1948 Israel proclaimed its independence, establishing a national home for the Jewish people following the horrors of the Holocaust. However, for Palestinians this proclamation was tied to the Nakba or catastrophe, a term used to mark their displacement, dispossession, and occupation. This cycle of violence has made ethical dialogue and the witnessing of the other’s trauma difficult. To begin bridging this divide, my dissertation takes up the impossible yet necessary task of “willing the impossible” (Butler, 2012, p. 222), which entails thinking the unequal yet bound tragedies of the Holocaust and the Nakba contrapuntally, morally and ethically engaging with alterity, and envisioning a new polity based on coexistence, justice, and equitable rights (Said, 2003). It does this by bringing Edward Said’s (2000; 1993; 1986) theories of narrative, memory, and photography, Hannah Arendt’s distinction between “fictional” and “real” stories (1998, p. 186), and Arielle Azoulay’s concept of “the civil contract of photography” (2008, p. 85) into praxis through a unique photograph-based storytelling method. First, I conducted interviews with Palestinians and Israelis living in their respective Canadian diasporas who are of the Holocaust and Nakba postmemory generations (Hirsch, 2012). During these interviews participants narrated their stories of how the Holocaust and/or the Nakba have impacted their lives using family photographs. Second, participants exchanged their stories and photographs with fellow participants from both cultures. Finally, I conducted a second round of interviews in which participants reflected on the experience of narrating their stories and photographs, engaging with the other participants’ stories and photographs, and the research process as a whole. Ultimately, my dissertation demonstrates that storytelling and photography enable the “occasions” (Fabian, 1990, p. 7) and “conditions of possibility” (Culhane, 2011, p. 258) necessary for willing the impossible through “civil imagination” (Azoulay, 2012, p. 5). That is, by narrating and exchanging their postmemories of the Holocaust and/or the Nakba through photographs, my participants were able to connect rather than compare their histories of suffering and exile, take moral, ethical, and political responsibility for one another, and imagine a new form of cohabitation grounded in justice and equitable rights for all.

Single crystals of RE3TMSb5 (RE = La, Ce; TM = Ti, Zr, Hf) have been grown by Sn flux and characterized by magnetization, electrical resistivity, and specific heat measurements. Powder X-ray diffraction analysis indicates that the title compounds crystallize into the hexagonal Hf5Sn3Cu-type structure (P63/mcm). The physical property measurements for Ce-containing compounds clearly indicate an antiferromagnetic ordering around 5 K. The effective magnetic moment estimated from magnetic susceptibility measurements is close to the theoretical value, indicating the 4f-electrons of Ce3+ ions are well localized. Magnetization isotherms at T = 2 K show anisotropic behaviour between H||ab and H||c. The temperature-dependent electrical resistivity follows a typical Kondo lattice behavior associated with thermal population of crystalline electric field (CEF) levels. The specific heat measurement for Ce-containing compounds reveals a large Cm/T value at low temperatures, which is much bigger than that of La-containing samples. At high temperatures, the CEF energy level scheme is analyzed by fitting to the Schottky peak observed in specific heat, from which the energy splitting levels between the three doublet states are found to be 165 and 380 K for all three Ce-containing samples. The resistivity measurements for all La-containing samples indicate an anomalous broad peak structure at high temperatures. We also investigate the previously reported superconductivity observed in La3TiSb5 and Ce3TiSb5 below 4 K. Our resistivity and specific heat measurements show that the superconductivity is not an intrinsic property of the single crystals, and is attributed to residual Sn flux.

To decipher the complex juxtaposition of laterally adjacent depositional environments that occur in the upper member of the McMurray Formation to the Wabiskaw Member, detailed sedimentological and ichnological analyses were undertaken. Thirteen facies and five facies associations are identified. The study interval consists of shallow-water deltaic to embayed shoreface successions, that increase in thickness and marine influence upwards. Allogenic and autogenic flooding surfaces were distinguished based on sedimentological, ichnological, and geophysical properties. Allogenic flooding surfaces were mapped across the study area, to identify the internal stratigraphic architecture of the upper member of the McMurray Formation. The thicknesses of individual deltaic shingles were identified by mapping their bounding autogenic flooding surfaces. Allogenic flooding surfaces were assessed to identify the viability of use as localized supplemental datums. During McMurray deposition the paleoshoreline evolved from an elongated restricted embayment to a less-confined, open embayment with more normal marine processes.