The diagnosis of IDCS can rarely be entertained on clinical information alone. Microscopically, there is a wide spectrum of features. Thus, immunohistochemistry and electron microscopy are crucial in making the diagnosis. The differential diagnosis includes inflammatory pseudotumour, follicular dendritic cell sarcoma, true histiocytic lymphoma, malignant Langerhans cell histiocytosis, anaplastic large-cell lymphoma, melanoma, and a range of sarcomas. IDCS displays aggressive behaviour and approximately half of the patients die of the disease.

Wind power installations are on the increase, globally and in South Africa. Several research areas are affected by this uptake of wind energy systems, which include wind generator performance and power system stability studies. Dimensional analysis is a very powerful tool. It allows machines and systems to be down-scaled in order to get a preliminary result before constructing a prototype by establishing laws of similitude between the original and its model. Studies using micromachines, a more accurate means of generator simulation, can be used to investigate issues of grid integration and dynamic performance of wind systems. Scaling methodologies are reviewed for use of the techniques for developing micromachines for wind generators.

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Within the context of the energy crisis in the Western Cape, the Provincial Government and Eskom (the South African power utility) embarked on a retrofit campaign to install 5 million compact fluorescent lamps (CFLs) in a desperate attempt to decrease the generation deficit. There is also increased pressure for investments in new generation capacity, with all options including the Pebble Bed Modular reactor (PBMR), the Open Cycle Gas Turbines (OCGT) as well as renewable resource technologies being pro-posed. Despite all these concerted efforts it is wide-ly regarded that demand-side technologies, with education programs, subsidies and research fund-ing, have greater scope for achieving success as they tackle the root cause rather than the symptom.The light emitting diode (LED) is a new energy efficient option in the lighting sector that has in recent times been deployed extensively by the City of Cape Town’s Transport Network Operations Department. The technology promises superior attributes that include a longer lifespan and higher energy conversion efficiencies, when compared to the traditional incandescents and fluorescents. This paper details the achievements of the LED in its brief history in the local traffic and signals industry as well as its projected impact on the city traffic light department’s future energy and mainte-nance budget. It is then proposed that these mono-chromatic signal LEDs, which is fast evolving into a white LED, holds the best promise in Cape Town as well as the Western Cape’s energy future if adopted for general lighting in the domestic, commercial and industrial market.