Losing your Senses and Shadows in the Sky

How do planes make shadows on the clouds? Can mosquitoes transmit HIV? Which sense do we lose last under anaesthetic? Drs Chris and Dave have the answers in this week's Ask the Naked Scientists when they also delve into cellulitis and how not to catch it, how athletes can constantly break world records, why men and women get fat in different places and why perpetual motion is a pipedream.