And the Hello and welcome to the naked scientist with me Chris Smith and with Cat Arnie.

This week we're donning our body armour and heading out into the battlefield to uncover the science behind warfare.

How do explosives work and what can we do to protect against them?

Plus the science headlines from across the world, including our antibiotics making us fat, the

comet that may have a cave inside it, and how to spot when your partner is ovulating.

The Naked Scientists Podcast is powered by UKfast.co.uk. First, millions of doses of antibiotics are administered every day, particularly to young

children. While their life-saving benefits speak for themselves, could there be a downside to antibiotic

exposure in early life?

A new study on young mice suggests that use of the drugs might be making children more

likely to become obese and causing lifelong changes to metabolism.

From the NYU Langone Medical Center, Martin Blazer.

I realize that farmers give antibiotics to their farm animals to improve their growth.

And about 10 years ago a light bulb went off and I thought maybe this is what we're doing to

our children.

We're causing them to grow more too.

So in recent years we've done studies in mice where we've given

the mice doses of antibiotics at the levels that farmers give. These are low doses given

every day in their drinking water and we found that the mice become fat.

And when we put them on a high-fat diet they become fat, when we put them on antibiotics,

they become fat, and when we put them on both together they become very

fat. But human children aren't getting low doses of antibiotics every day. They're

getting pulses of antibiotics to treat their ear infections and their throat infections.

...