University of Saskatchewan

About: University of Saskatchewan is a education organization based out in Saskatoon, Saskatchewan, Canada. It is known for research contribution in the topics: Population & Health care. The organization has 25021 authors who have published 52579 publications receiving 1483049 citations. The organization is also known as: USask.

Application of a distributed blowing snow model to the arctic

Abstract: Transportation, sublimation and accumulation of snow dominate snow cover development in the Arctic and produce episodic high evaporative fluxes. Unfortunately, blowing snow processes are not presently incorporated in any hydrological or meteorological models. To demonstrate the application of simple algorithms that represent blowing snow processes, monthly snow accumulation, relocation and sublimation fluxes were calculated and applied in a spatially distributed manner to a 68-km 2 catchment in the low Arctic of north-western Canada. The model uses a Landsat-derived vegetation classification and a digital elevation model to segregate the basin into snow ‘sources’ and ‘sinks’. The model then relocates snow from sources to sinks and calculates in-transit sublimation loss. The resulting annual snow accumulation in specific landscape types was compared with the result of intensive surveys of snow depth and density. On an annual basis, 28% of annual snowfall sublimated from tundra surfaces whilst 18% was transported to sink areas. Annual blowing snow transport to sink areas amounted to an additional 16% of annual snowfall to shrub‐tundra and an additional 182% to drifts. For the catchment, 19.5% of annual snowfall sublimated from blowing snow, 5.8% was transported into the catchment and 86.5% accumulated on the ground. The model overestimated snow accumulation in the catchment by 6%. The application demonstrates that winter precipitation alone is insuAcient to calculate snow accumulation and that blowing snow processes and landscape patterns govern the spatial distribution and total accumulation of snow water equivalent over the winter. These processes can be modelled by relatively simple algorithms, and, when distributed by landscape type over the catchment, produce reasonable estimates of snow accumulation and loss in wind-swept regions. #1997 John Wiley & Sons, Ltd.

Behavioral and neurobiological consequences of prolonged glucocorticoid exposure in rats: relevance to depression

Abstract: Stress is a critical environmental trigger for the development of clinical depression, yet little is known about the specific neurobiological mechanisms by which stress influences the development of depressive symptomatology. Animal models provide an efficient way to study the etiology of human disorders such as depression, and a number of preclinical models have been developed to assess the link between stress, glucocorticoids, and depressive behavior. These mode ls typically make use of repeated exposure to physical or psychological stressors in rodents or other small laboratory animals. This review focuses primarily on a recently developed preclinical model of depression that uses exogenous administration of the stress hormone corticosterone (CORT) in rodents instead of exposure to physical or psychological stressors. Repeated CORT administration in rats or mice produces reliable behavioral and neurobiological alterations that parallel many of the core symptoms and neurobiological changes associated with human depression. This provides an opportunity to study behavior and neurobiology in the same animal, so that the neurobiological factors that underlie specific symptoms can be identified. Taken together, these findings suggest that exogenous CORT administration is a useful method for studying the relationship between stress, glucocorticoids, and depression. Further study with this model may provide important new data regarding the neurobiological bases of depression.

Cost-effective wind energy utilization for reliable power supply

Abstract: Environmental concerns and fuel cost uncertainties associated with the use of conventional energy sources have resulted in rapid growth of wind energy applications in power generating systems. It is important to assess the actual cost and benefit of utilizing wind energy in a power system. Such assessments require realistic cost/reliability evaluation methods and quantitative indices. This paper presents a simulation technique that generates probabilistic indices that can help determine appropriate wind power penetration in an existing power system from both the reliability and economic aspects.

Treatment of chronic pain with spinal cord stimulation versus alternative therapies: cost-effectiveness analysis.

Abstract: There is limited available research measuring the cost-effectiveness ofspinal cord stimulation (SCS), compared with best medical treatment/conventionalpain therapy (CPT). The purpose of this study was to tabulate the actual costs (inCanadian dollars) for a consecutive series of patients treated with SCS in a constanthealth care delivery environment and to compare the costs with those for a controlgroup treated in the same controlled environment.