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A study on the fabrication of yttrium-barium-copper-oxide superconductors is presented. It tackles the Melt Textured Growth method and the Isothermal Melt Textured approach which improves on the slow cooling and temperature gradient of the former. This enhancement is achieved by capitalizing on the system's melting point being a function of oxygen partial pressure. An experiment to to evaluate such a scheme resulted in superconductors with a large grain microstructure.

This study investigated basketball players' preferences for different decision making styles in varying situations. While females were more oriented toward participation than males were, preferences of both groups were more influenced by main effects of coach's information and the interaction of quality requirement with problem complexity. (Author/MT)

In the complex field of design, which bridges art and science, designers need to be critically aware and versatile. They should possess breadth and depth of knowledge, skills and understanding that can be transferred and adapted to new and different situations, enabling sustainable and innovative design solutions. Designers need to communicate within a global 'networked knowledge society'. It has been argued that 'designers create culture' and that the knowledge and hand skills traditionally required of an artist/designer are essential, as design outcomes are purpose driven and practical. Self-awareness and confidence have been identified as necessary attributes for 'creative design action'. This article reports on a longitudinal, interpretive study of the role of tertiary design foundation education and in particular an integrated, multidisciplinary Design Foundation Course in the South African context. In raising students' critical awareness by instilling an understanding of 'core ideas' and the 'visual language' specific to the fields of art and design, emphasis was placed on 'learning to see' through the act of drawing and the use of colour. Transference from one studio-based subject to another, that takes place through studio group critiques applying comparative analysis as a means of formative assessment, was examined. The iterative nature of the design process in encouraging 'design thinking', described as 'reflection in action', and which leads to the development of generative self-criticism, was investigated. It is argued that generative self-criticism in students provides an essential benchmarking instrument for the assessment of practical design outputs. [ABSTRACT FROM AUTHOR]

Cytotoxic T cells are believed to be an important immune response in HIV infection, both in the initial response to viraemia, and in controlling HIV replication and maintaining clinical stability. We report here the detailed findings in two vertically infected children, from the Edinburgh perinatal cohort. Both were clinically stable for the first 7 years of life. One had vigorous HIV-specific cytotoxic T lymphocyte (CTL) responses, and non-lytic suppression, measured in vitro, while the second had no CTL activity against HIV. Despite her HIV-specific immunity, the first child had a declining CD4 count, and a high and fluctuating viral load, whereas the second child maintained a stable CD4 count, a low viral load and had a virus which could not be cultured in peripheral blood mononuclear cells (PBMC) in vitro. The first child subsequently progressed to AIDS and has now died, while the second remains clinically well. More detailed investigations showed the clinically stable child lo be heterozygous for the CCR5 receptor, and to be HLA-B49--both of which markers have been associated with slow HIV disease progression. These findings question the role of CTL in maintaining stable HIV disease, and stress the need for immunological investigations to be considered in the light of the genetic make-up of the patient. They may also reflect a different immunopathogenesis of HIV disease in children compared with adults. [ABSTRACT FROM AUTHOR]

Therapeutic concentrations (0·3–1·5 mg/l) of pentamidine isethionate and pentamidine mesylate, obtained after parenteral administration of either drug, did not affect oxygen consumption in the stimulated neutrophilic granulocyte. At concentrations of 0·7, 1·1 and 1·5 mg/l, superoxide production, hydrogen peroxide production, myeloperoxidase (MPO)-mediated iodination and hexose monophosphate shunt activity were suppressed relative to untreated cells ( < 0·001 in each case). The depression in each activity was dose-related. There was no significant difference between the drugs with regard to these impairments in neutrophilic granulocyte function. This lowered respiratory burst activity, which would lead to a depression of MPO-dependent and MPO-independent processes in stimulated neutrophilic granulocytes, may be due to drug induced dysfunction of NADPH-oxidase. [ABSTRACT FROM PUBLISHER]

Therapeutic concentrations (0.3-1.5 mg/l) of pentamidine isethionate and pentamidine mesylate, obtained after parenteral administration of the drugs, did not influence neutrophilic granulocyte adherence, random and chemotactic migration or phagocytosis of Candida albicans spores in vitro. At concentrations of 0.7, 1.1 and 1.5 mg/l, the ability of neutrophilic granulocytes to kill C. albicans spores was depressed (P less than 0.001); at all concentrations used, their ability to reduce nitroblue tetrazolium was decreased (P less than 0.001). There was no significant difference between the drugs with regard to these impairments in neutrophilic granulocyte function. It is likely that pentamidine salts inhibit superoxide radical formation in the stimulated neutrophilic granulocyte and that this dysfunction leads to depressed intracellular killing of C. albicans spores. [ABSTRACT FROM AUTHOR]

Home-cage running-wheel activity of mice congentally infected with Toxoplasma was recorded over 24 days. Infected mice were consistently more active than uninfected controls over the entire testing period. This finding extends previous studies and indicates that such increased activity levels occur not only in novel but also in familiar environments, and suggests that congenital toxoplasmosis tends to render mice 'hyperactive'. If such behavioural alterations occur in wild mice, it is likely that infected mouse intermediate hosts would be more susceptible to predation by cats, the definitive hosts of Toxoplasma. [ABSTRACT FROM AUTHOR]

Preincubation of CD4 lymphocytes with pentamidine isethionate at a concentration of 1.5 mg/L then removal from incubation medium prior to addition of HIV-1, or incubation of cells with the drug and virus simultaneously, increased HIV-1 DNA load but reduced p24 antigen release. The number of syncytia generated was not affected by the presence of pentamidine. The extent of balloon degeneration of cells was greater, however, although this was not associated with a discernable increase in cellular necrosis or reduction in cell viability. This suggests that drug-treatment resulted in an increased load of intracytoplasmic (but not necessarily integrated) forms of HIV- 1; this may explain the lower levels of antigen produced and also the balloon degeneration of treated cells, a phenomenon previously observed with other retroviruses. [ABSTRACT FROM AUTHOR]