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To minimise an open cast mine's environmental footprint and liabilities, mine operators should consider the aesthetics of the landform post closure, how the landform will function and interact with the surrounding features and drainage, and how the landform and landscape will perform after mine closure. Planning should also consider how the landform will be constructed to minimise environmental issues during construction. The development of a knowledge base is essential for closure planning, and information should be gathered throughout the life of a mine. Design decisions should take into account physical constraints of the site, drainage, waste material volumes and type, types of covers that may be required, surface water, erosional stability, hydrogeology, and geomorphic principals and landscape modelling. Predictive mine modelling can be used to develop a realistic post-mining model of an open cast mine, and material movement during mining optimised to achieve elevations and positions close to the proposed rehabilitated topography., To minimise an open cast mine's environmental footprint and liabilities, mine operators should consider the aesthetics of the landform post closure, how the landform will function and interact with the surrounding features and drainage, and how the landform and landscape will perform after mine closure. Planning should also consider how the landform will be constructed to minimise environmental issues during construction. The development of a knowledge base is essential for closure planning, and information should be gathered throughout the life of a mine. Design decisions should take into account physical constraints of the site, drainage, waste material volumes and type, types of covers that may be required, surface water, erosional stability, hydrogeology, and geomorphic principals and landscape modelling. Predictive mine modelling can be used to develop a realistic post-mining model of an open cast mine, and material movement during mining optimised to achieve elevations and positions close to the proposed rehabilitated topography.

Some of the fundamental rock-mass and support engineering criteria that form the basis of an improved methodology for designing support are reviewed: height of potential fall; quasi-static stope closure rates; dynamic stope closure rates; compressive hangingwall stresses; discontinuity spacing, orientation and interface properties; effect of support length (stoping width); effect of compression rate; consistency of support performance; areal coverage; support spacing; and zone of support influence. The site-specific methodology consists of two stages: the spacing requirements of tributary areas are first analysed and an analysis is then made of stability and the influence of the zone of support, considering hangingwall failure due to buckling, shear and block rotation. It is suitable for both blocky hangingwalls and those fragmented by face-parallel extension and shear fractures., Some of the fundamental rock-mass and support engineering criteria that form the basis of an improved methodology for designing support are reviewed: height of potential fall; quasi-static stope closure rates; dynamic stope closure rates; compressive hangingwall stresses; discontinuity spacing, orientation and interface properties; effect of support length (stoping width); effect of compression rate; consistency of support performance; areal coverage; support spacing; and zone of support influence. The site-specific methodology consists of two stages: the spacing requirements of tributary areas are first analysed and an analysis is then made of stability and the influence of the zone of support, considering hangingwall failure due to buckling, shear and block rotation. It is suitable for both blocky hangingwalls and those fragmented by face-parallel extension and shear fractures.

South African canine babesiosis is caused by the virulent Babesia canis rossi. In recent years, this common disease has been detected in 12% of dogs presented at the outpatients' division of the University of Pretoria's (Onderstepoort) Veterinary Academic Hospital, and 31% of the affected dogs have been hospitalized as seriously ill. Of these hospitalized cases, 50% had severe anaemia at presentation, 32% had moderate anaemia and 18% were non-anaemic (often polycythaemic), frequently with central-nervous-system signs or multiple organ failure. A retrospective survey of 662 hospitalized cases revealed that the haematology, clinical biochemistry and patient profile (signalment) of the severely anaemic dogs were distinct from those of the non-anaemic, indicating that the babesiosis in these two groups of dogs should be viewed as two different disease in terms of the postulated, underlying, 'pathomechanisms'. The severely anaemic dogs exhibited hypoxic hepatic disease and an increase in serum urea (without a concomitant increase in creatinine), seldom had profound electrolyte imbalances and tended to have a much more profound leucocytosis, consisting of a left-shifted inflammatory leucogram, with higher numbers of circulating metamyelocytes, lymphocytosis and monocytosis. In contrast, the non-anaemic dogs exhibited severe azotaemia (which could be of renal or pre-renal origin) and often showed a marked electrolyte disturbance (reflecting acid-base abnormalities) and a very mild leucocyte response; such dogs often presented as leucopenic, many being lymphocytopenic. These results indicate that the severely anaemic dogs had developed haemolytic disease (possibly immune-mediated), whereas the non-anaemic dogs had developed an acute and overwhelming inflammatory response. The mean age of the non-anaemic dogs (2.66 years) was less than the dogs in the 'severe anaemia group' (0.83 years). Dogs belonging to the traditional fighting breeds (bull terriers, pit bull terriers and