Publications by authors named "G E Bradfield"

Forests are being clearcut over extensive areas of western North America, but plant community response to harvesting and slashburning under varying climatic conditions in central British Columbia, Canada is still largely unknown. Evaluation of resilience is hampered by the short history of logging, lack of long-term experiments and methodological limitations. To test the effect of clearcut logging, prescribed burning and reforestation on forest resilience, we recorded vascular plant cover repeatedly after treatment between 1981 and 2008 in 16 permanent research installations in three biogeoclimatic zones: Engelmann Spruce-Subalpine Fir, Interior Cedar-Hemlock and Sub-Boreal Spruce.

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During oil-sands mining all vegetation, soil, overburden, and oil sand is removed, leaving pits several kilometers wide and up to 100 m deep. These pits are reclaimed through a variety of treatments using subsoil or a mixed peat-mineral soil cap. Using nonmetric multidimensional scaling and cluster analysis of measurements of ecosystem function, reclamation treatments of several age classes were compared with a range of natural forest ecotypes to discover which treatments had created ecosystems similar to natural forest ecotypes and at what age this occurred.

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Blood samples were collected from sheep on 24 farms in the Natal Midlands to ascertain the selenium, copper and zinc status of sheep kept under intensive grazing conditions on cultivated pastures in this region. The mean erythrocyte glutathione peroxidase activity was 34.1 enzyme units (EU: nmol NADPH oxidised min-1 mg-1 haemoglobin).

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The response to selenium supplementation of sheep grazing cultivated pastures was investigated on different farms in the Natal Midlands, Republic of South Africa. Over a period of one year, a significant (P < 0.01) improvement of 18.

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MISC of the cervix is a potentially fatal disease if not properly classified and treated. Strict criteria for diagnosis are required to provide appropriate therapy. It is recommended that a radical approach be considered for those patients in whom the depth of invasion of the carcinoma is greater than 3 mm on cone biopsy and in all cases where vascular invasion is demonstrated.

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