Mark Wallinger unveiling one of his 270 pieces for each of the stations on London Underground network.
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Five-year-old Yusuf Abdismad died from meningitis in January after a mix-up between emergency operators, it has emerged.
A strike by members of four unions, RMT, Aslef, TSSA and Unite, is expected to bring the Underground to a standstill tomorrow evening.
Official readings are recorded three metres in the air but a study found levels of nitrogen dioxide (NO2) were higher at pushchair level.