This week, Chris Smith and Izzie Clarke are taking you to the cutting edge of materials science including how blacksmiths made incredibly tough swords to how defence scientists make bullet-proof armour today. Plus, news of a better way to manage prostate cancer, how fingerprints might replace chip n pin, and how scientists are using cold lightning to keep fruit fresh for longer.For more podcasts by The Naked Scientists, head to nakedscientists.com, find @NakedScientists on Facebook, Twitter and Instagram and subscribe to "The Naked Scientists" on your favourite podcast app.**Edinburgh Science... Like this podcast? Please help us by supporting the Naked Scientists