Blue Peter stretch of track which, on 3 July 1938, saw the world speed record for steam locomotives of set by LNER A4 Locomotive no. 4468 "Mallard". In October 1998, Richard Bacon was sacked, following reports in "News of the World" that he had taken cocaine. This incident followed shortly after the show's 40th anniversary, when previous presenters returned for a special programme. Those returning included Leila Williams, Valerie Singleton, John Noakes, Peter Purves, Diane Louise Jordan, Anthea Turner, John Leslie, Tim Vincent, Yvette Fielding, Caron Keating, Mark Curry, Janet Ellis, Peter Duncan, Sarah Greene, Tina Heath, Simon Groome and Christopher Wenner.
Epigenetics of cocaine addiction concluded that ΔFosB, CREB, Sirt1 and Sirt2 all play an integral role in cocaine-seeking behaviors. Kumar et al. focused on how acute and chronic cocaine exposure affected the striatum, which is another area of the brain involved in the reward and locomotor pathways. To study the molecular actions of cocaine in this region, researchers studied the histone modifications of three different promoters: "cFos", "BDNF", and "Cdk5". They saw that "cFos", which is normally expressed immediately after neurons fire action potentials, had high levels of H4 acetylation within 30 minutes of a cocaine injection – but no histone modifications were seen