Members of the armed forces are trained to battle the enemy. And to fight effectively, they also have to be ready to battle other forces – things like panic, exhaustion and extreme temperatures. This hour, guest host Lauren Silverman will talk about how the Department of Defense is using technology and training to best equip military personnel with Mary Roach. She’s the author of “Grunt: The Curious Science of Humans at War” (W.W. Norton and Co.).