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Fungus-like protuberances can help tall chimneys and towers withstand high winds, according to scientists at Imperial College, London (GB 2 362 938). If smoothly curved 鈥済rowths鈥�, like bracket fungi on a tree, are regularly spaced around a chimney, wind drag is drastically reduced. The best size for the protuberance is between a quarter and a half the chimney鈥檚 diameter, with a repeat distance of around six times the diameter. The same system could allow oil rigs and wind-turbine supports to resist winds, Imperial says. It could also be used on undersea cables to reduce tidal drag.