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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
171

Regional Assessment of Glacier Motion in Kluane National Park, Yukon Territory

Waechter, Alexandra 21 November 2013 (has links)
This project presents regional velocity measurements for the eastern portion of the St. Elias Mountains, including the entire glaciated area of Kluane National Park, derived from speckle tracking of Radarsat-2 imagery acquired in winter 2011 and 2012. This technique uses a cross-correlation approach to determine the displacement of the ‘speckle’ pattern of radar phase returns between two repeat-pass images. Further reconstruction of past velocities is performed on a selection of key glaciers using feature tracking of Landsat-5 imagery, allowing for the investigation of variability in glacier motion on interannual and decadal time scales. The results of the analysis showed that there is a strong velocity gradient across the region reflecting high accumulation rates on the Pacific-facing slope of the mountain range. These glaciers may have velocities an order of magnitude greater than glaciers of a similar size on the landward slope. Interannual variability was high, both in relation to surge events, of which a number were identified, and variation of other unknown controls on glacier motion. A long-term trend of velocity decrease was observed on the Kaskawulsh Glacier when comparing the results of this analysis to work carried out in the 1960s, the pattern of which is broadly congruent to measurements of surface elevation change over a similar period.
172

Applying the Apriori and FP-Growth Association Algorithms to Liver Cancer Data

Pinheiro, Fabiola M. R. 27 August 2013 (has links)
Cancer is the leading cause of deaths globally. Although liver cancer ranks only fourth in incidence worldwide among all types of cancer, its survivability rate is the lowest. Liver cancer is often diagnosed at an advanced stage, because in the early stages of the disease patients usually do not have signs or symptoms. After initial diagnosis, therapeutic options are limited and tend to be effective only for small size tumors with limited spread and minimal vascular invasion. As a result, long-term patient survival remains minimal, and has not improved in the past three decades. In order to reduce morbidity and mortality from liver cancer, improvement in early diagnosis and the evaluation of current treatments are essential. This study tested the applicability of the Apriori and FP-Growth association data mining algorithms to liver cancer patient data, obtained from the British Columbia Cancer Agency. The data was used to develop association rules which indicate what combinations of factors are most commonly observed with liver cancer incidence as well as with increased or decreased rates of mortality. Ideally, these association rules will be applied in future studies using liver cancer data extracted from other Electronic Health Record (EHR) systems. The main objective of making these rules available is to facilitate early detection guidelines for liver cancer and to evaluate current treatment options. / Graduate / 0566 / 0984 / fabiola@uvic.ca
173

The biotic and abiotic interactions influencing organochlorine contaminants in temporal trends (1992-2003) of three Yukon lakes: focus on Lake Laberge

Ryan, Michael J. 29 March 2007 (has links)
Periodic monitoring of contaminant levels in fish from the Yukon Territory indicated that organochlorine (OC) contaminants had rapidly declined since the early 1990s. This study examined OC concentrations, including chlordane (sigma-CHL), sigma-DDT, hexachlorocyclohexane (sigma-HCH), toxaphene (sigma-CHB), sigma-PCB and chlorinated benzenes (sigma-CBz) in sentinel fish (species of consistent annual observation and collection) from two Yukon lakes (Kusawa, Quiet), and from the aquatic food web of a focus lake (Lake Laberge) across several temporal points between 1993 and 2003. OC analysis and phytoplankton counts from dated sediment cores as well as climate data were also collected. Population, morphological (length, weight, age), biochemical (lipid content, delta-13C, delta-15N) and OC contaminant data for fish and invertebrates (zooplankton, snails, clams) were reviewed to elucidate the primary causes for these OC declines. Although some spatial differences in contaminant levels exist between the Yukon lakes, OC concentrations were declining for lake trout in all three lakes, with declines also noted for burbot from Lake Laberge. Several other fish species as well as zooplankton from Lake Laberge exhibited decreases in contaminant levels except northern pike, which registered consistently higher levels from 1993 to 2001. There was no evidence to support the hypotheses of changes in fish trophic levels or food sources with the exception of burbot, which marginally decreased, and northern pike, which climbed a half trophic level. Through OC flux analysis in dated sediments, the hypothesis that declines in abiotic deposition affected the contaminant levels in the food web was also negated. The closure of the Lake Laberge commercial fishery resulted in faster fish growth and larger fish populations, which are contributing to biomass dilution of OC concentrations, higher OC biomagnification factors for some species and likely changes in predator-prey interactions as resource competition increases. The large ratio of OC decreases in the lower vs. higher trophic levels of Lake Laberge have increased food web magnification factors (FWMF) for all six OC groups. It is also suspected that above-average temperatures and below-average precipitation in the lower Yukon region over the 1990s may have contributed towards an increase in lake primary production resulting in biomass dilution of contaminants in zooplankton for all three study lakes. Concurrently, shifts in the Lake Laberge zooplankton community, from climate fluctuations or increased fish predation, have gone from an abundance of Cyclops scutifer in 1993 to dominance by Diaptomus pribilofensis in 2001, although sample sites were limited. Characteristics specific to each species (e.g. body size, composition and metabolism) likely play a role in the significant OC declines measured in zooplankton. Fluctuations in population dynamics, species characteristics and OC contaminant concentrations in the Lake Laberge ecosystem may continue for several years to come. Sentinel species such as lake trout, burbot, whitefish, cisco and plankton should continue to be monitored in all three Yukon lakes for future temporal correlations with contaminants or climate change.
174

The development of a curriculum for the nominating committee of Canadian Valley Baptist Church, Yukon, OK, to assess members' spiritual giftedness and place them in service

Kellogg, Kevin Allen. January 2005 (has links)
Thesis (D. Min.)--Midwestern Baptist Theological Seminary, 2005. / Abstract. Includes bibliographical references (leaves 157-158)
175

A Geochemical Characterization of a Cold-Water Acid Rock Drainage Stream Emanating From the Zn-Pb XY-deposit, Howard's Pass, Yukon Territory, Canada

Feige, Kristen B. January 2011 (has links)
An acid rock drainage (ARD) stream emanating from the Zn-Pb XY-deposit in the Yukon Territory was examined in order to evaluate the physico-chemical and geochemical processes governing the distribution of dissolved elements from the creek. The creek showed very high concentrations of metals (300 mg/L Fe, 500 mg/L Zn, 15 000 µg/L Ni, 1300 µg/L Cu and 4500 µg/L Cd), low water temperatures (1 – 12°C) and was acidic to moderately acidic (pH 3.1 – 5.0). It was found that this stream experienced a strong seasonal evolution, with increased sulphate and metal concentrations and decreased pH over the course of the summer. The mineral precipitates that formed under low pH conditions were a mixture of schwertmannite, goethite, jarosite and barite, while those that formed under moderately acidic conditions were a mixture of jurbanite, hydrobasaluminite, gibbsite and an X-ray amorphous Al-sulphate phase. Most of the mineral precipitates were of inorganic origin, although microbes may have played a role in mineral formation and trace metal sequestration in some of the precipitates. All of the mineral precipitates contained anomalous concentrations of trace elements (up to 1.5 % wt Zn) and showed a seasonal evolution in their mineralogy, both of which were determined to be a function of the pH and prevailing geochemical conditions. The geochemistry of the ARD creek draining the XY-deposit was compared to another ARD creek in the area that was likely draining shales. The two creeks were compared in order to determine if ARD geochemical characteristics can be used as a tool for the mineral exploration industry.
176

Solitudes in Shared Spaces: Aboriginal and EuroCanadian Anglicans in the Yukon and the Northwest Territories in the Post-Residential School Era

Cheryl, Gaver January 2011 (has links)
This thesis examines the current relationship between Aboriginal and EuroCanadian Anglicans in the Northwest Territories and the Yukon as they seek to move beyond past hurts into a more positive future. After three field trips to Canada's North, visiting seven communities and interviewing seventy-nine individuals, complemented by archival research, I realized the dominant narrative based on a colonialism process linking residential schools, Christian Churches and federal government in a concerted effort to deliberately destroy Aboriginal peoples, cultures, and nations was not adequate to explain what happened in the North or the relationship that exists today. Two other narratives finally emerged from my research. The dominant narrative on its own represents a simplistic, one-dimensional caricature of Northern history and relationships. The second narrative reveals a more complex and nuanced history of relationships in Canada's North with missionaries and residential school officials sometimes operating out of their ethnocentric and colonialistic worldview to assimilate Aboriginal peoples to the dominant society and sometimes acting to preserve Aboriginal ways, including Aboriginal languages and cultures, and sometimes protesting and challenging colonialist policies geared to destroying Aboriginal self-sufficiency and seizing Aboriginal lands. The third narrative is more subtle but also reflects the most devastating process. It builds on what has already been acknowledged by so many: loss of culture. Instead of seeing culture as only tangible components and traditional ways of living, however, the third narrative focuses on a more deep-seated understanding of culture as the process informing how one organizes and understands the world in which one lives. Even when physical and sexual abuse did not occur, and even when traditional skills were affirmed, the cultural collisions that occurred in Anglican residential schools in Canada's North shattered children's understanding of reality itself. While the Anglican Church is moving beyond colonialism in many ways - affirming Aboriginal values and empowering Aboriginal people within the Anglican community, it nevertheless has yet to deal with the cultural divide that continues to be found in their congregations and continues to affect their relationship in Northern communities where Aboriginal and EuroCanadian people worship together yet remain separate.
177

Pleistocene and Holocene Climate Reconstruction at Two Moose Lake, Central Yukon, Using Stable Isotopes and 14C-DOC Radiocarbon from Ice wedges, Pore Ice and Buried Sediments

Grinter, Michael January 2017 (has links)
The objective of this thesis was to reconstruct the Sedimentary, Cryostratigraphic and Paleoclimatic history of Two Moose Lake, central Yukon using a new analytical technique for dating ice wedges using Dissolved Organic Carbon (DOC). During two field seasons in August 2013 and April 2014, 442 samples were collected from a newly exposed headwall of a thaw slump with 7 ice wedges and over 4m of sediment. Using cryostratigraphy, granulometry, stable isotopes and 18 14C-DOC ages, 4 stratigraphic units were delineated: 1) a sediment-rich ice layer inferred to be of glacial origin (>32ka BP); 2) a silt-rich layer deposited during the Holocene Thermal Maximum (~10 to 8.2ka BP); 3) a silt with organics layer deposited from ~8ka to 6.4ka BP, and 4) a paleo-active layer and modern active layer. 14C-DOC dating indicated two periods of ice wedge activity at Two Moose Lake, the first during the late Pleistocene (31,608 to 12,990 yr cal BP) and from the mid-Holocene to present (6,328 to 892 yr cal BP). The presence of late-Pleistocene aged ice wedges at Two Moose Lake supports the common belief of an unglaciated central Yukon during the most recent McConnell glaciation from 29.6 to 13ka BP. Values for δ18O from the Holocene- and Pleistocene-aged ice wedges were 2-3‰ and 5-9‰ depleted compared those of modern precipitation from Mayo (-22.32‰). Medium-resolution (2-4cm) sampling along with multiple 14C-DOC samples along a transect allowed for the creation of a continuous δ18O and temperature age profile to be developed from multiple ice wedges, showing a strong consistency between overlapping ages. The reconstruction of the paleoclimate of Two Moose lake is consistent with known events from southern Yukon including the Boutellier Inderstadial, a cold unglaciated central Yukon during the McConnell Glaciation, warming during the Holocene Thermal Maximum (HTM) followed by an extreme cooling event at 8.2ka BP, a cooling event at 4.2ka BP, and the subsequent warming to present temperatures.
178

Structure socio-culturelle et rapports de domination chez les Indiens Tutchone septentrionaux du Yukon au dix-neuvieme siecle

Legros, Dominique January 1981 (has links)
La société tutchone (Yukon) du XIXe siècle reposait sur une économie de chasse, pêche et cueillette des plus élémentaires. Pourtant, selon la tradition orale autochtone contemporaine, elle connaissait une fprme de stratification avec division de la population en gens riches; pauvres et esclaves; un fait très rare dans les sociétés de ce genre. Ces données conduisent à s'interroger sur deux plans. D'une part, les rapports de domination/subordination évoqués ont-ils vraiment existes? Peut-on reconstituer l'ensemble de l'organisation socio-culturelle d'alors? D'autre part,ssi oui, comment s'explique le fait que certaines familles parvenaient à s'enrichir et à prendre quelques Tutchone en esclavage? Les chapitres II à VII sont consacrés aux premières interrogations. Ils montrent que les oui-dire des Tutchone contemporains correspondent sans aucun doute possible à des faits réels et qu'il est possible de reconstituer l'organisation socio-culturelle en s'aidant des connaissances des Tutchone et des données fournies par les premiers explorateurs blancs. Le chapitre VIII est consacré à la deuxième question. L'explication proposée est la suivante. Le mariage entre cousins germains croisés bilatéraux répété génération après génération produisait des ensembles pourvus d'emblée d'une forte cohésion. Par contre, le mariage entre simples cousins classificatoires croisés bilatéraux produisait des ensembles hétérogènes peu capables d'agir en commun. La possibilité de rapports de domination/subordination entre Tutchone provenait de cette dichotomie. Les ensembles rendus fortement cohésifs par la pratique du mariage entre cousins germains croisés détenaient le pouvoir de contraindre par la force les membres des ensembles humains désintégrés, en tant que groupes, par des unions entre cousins croisés classificatoires. Les ensembles cohésifs se servaient de cette marge de manoeuvre pour mettre en esclavage les Tutchone les plus isolés sur le plan social, pour s'arroger le contrôle du commerce et des zones écologiques, les meilleures. / Arts, Faculty of / Anthropology, Department of / Graduate
179

Permafrost Changes Along the Alaska Highway Corridor, Southern Yukon, from Ground Temperature Measurements and DC Electrical Resistivity Tomography

Maxime Arsène, Duguay January 2013 (has links)
Permafrost temperatures were measured by the Geological Survey of Canada (GSC) in 1977-1981 at boreholes along a proposed pipeline route in the southern Yukon. Analysis of climate station records indicate that mean annual air temperatures in the region have since increased by 0.5-1.0˚C. Renewed interest in the pipeline and the need to develop adaptation strategies for existing highway infrastructure have meant that information on permafrost and geotechnical conditions must be updated. To accomplish this goal, a total of eight GSC boreholes ranging in depth from 5-9 m were located, unblocked of ice and instrumented with thermistor cables and data-loggers to permit renewed ground temperature monitoring. Manual temperature measurements were also taken at four other shallow boreholes. Electrical resistivity tomography (ERT) surveys were conducted at each site. MAGTs below 1 m at permafrost sites in the study area range from -0.2˚C to -1.5˚C with permafrost depths greater than 25 m. The permafrost at the study sites can be classified as sporadic discontinuous and extensive discontinuous. Ground temperatures indicate that permafrost can persist under warmer climatic conditions as long as it remains protected by its ecosystem properties. Thermal monitoring for 2011-2012 shows an average increase of 0.5-1.0˚C when compared to the original 1978-1981 ground temperatures. This slow rate of ground warming is mainly attributed to a combination of limited climate change, especially in the south of the study area, ground temperatures close to 0˚C, and the possible disturbance of sites from the removal of vegetation prior to the original measurements being made. ERT surveys conducted at most borehole sites show deeper thaw or taliks where the cleared cut-line used for geophysical work in the 1970s is crossed. These results indicate the impacts of climate change and environmental change in the study area over the past three decades. They appear to match the relatively slow rates of ground warming observed elsewhere in northern Canada where permafrost temperatures are close to 0˚C and where warming also requires changes in latent heat due to internal thaw. TTOP equilibrium modelling suggests that if climate change is responsible for the ground warming, most of the change can be attributed to the step-like MAAT increase that occurred between 1975-1976.
180

Regional Assessment of Glacier Motion in Kluane National Park, Yukon Territory

Waechter, Alexandra January 2013 (has links)
This project presents regional velocity measurements for the eastern portion of the St. Elias Mountains, including the entire glaciated area of Kluane National Park, derived from speckle tracking of Radarsat-2 imagery acquired in winter 2011 and 2012. This technique uses a cross-correlation approach to determine the displacement of the ‘speckle’ pattern of radar phase returns between two repeat-pass images. Further reconstruction of past velocities is performed on a selection of key glaciers using feature tracking of Landsat-5 imagery, allowing for the investigation of variability in glacier motion on interannual and decadal time scales. The results of the analysis showed that there is a strong velocity gradient across the region reflecting high accumulation rates on the Pacific-facing slope of the mountain range. These glaciers may have velocities an order of magnitude greater than glaciers of a similar size on the landward slope. Interannual variability was high, both in relation to surge events, of which a number were identified, and variation of other unknown controls on glacier motion. A long-term trend of velocity decrease was observed on the Kaskawulsh Glacier when comparing the results of this analysis to work carried out in the 1960s, the pattern of which is broadly congruent to measurements of surface elevation change over a similar period.

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