Australian scientists believe they have rediscovered an effective use for lemon juice - as a contraceptive and also a killer of the AIDS virus. Reproductive physiologist Roger Short, from the University of Melbourne's obstetrics department, said a few drops of lemon juice can be a cheap, easy-to-use solution to protect women from both HIV and pregnancy. The juice should be squeezed onto a piece of sponge or cotton wool and placed into the vagina before sex, he told Jonica Newby from ABC Television's Catalyst program. The program will be aired on the ABC tonight at 8.00pm AEST. "We can show...