Part one of an interview with Sunil Shaunak on 'ethical drugs' for Hepatitis C.

Dr Michael Beasley and Alice Woolnough on a scheme to keep HIV positive teachers in Africa in schools.

Professor Roger Greenhalgh on why too many limb amputations are taking place.

Lars Jarup on why aircraft noise can raise blood pressure even while you sleep.

Dr Julian Asher on synaesthesia and the genetics of obesity.

Graham Neale on understanding why doctors can misdiagnose their patients' conditions - and trying to prevent this.

Dr Tom Churcher on a new play that demonstrates why we all have a responsibility to be vaccinated.

Professor Peter Barnes on tackling one of the world's biggest killers - Chronic Obstructive Pulmonary Disease.

Dr Robin Walters on the genetic basis of obesity.

Vivette Glover and colleagues on telling children about maternal health at the Big Bang Science Fair.