So far, scientific research on a possible link between cell phone use and brain tumors has been contradictory. For those who believe an ounce of prevention couldn’t hurt, case-mate and Pong Research are launching a new line of smartphone cases that the companies claim can redirect radiation away from a user’s head. The “Bounce” cases contain a paper-thin internal circuit board that reduces constant cell phone radiation by at least 60 percent and hot spot radiation by at least 85 percent, without reducing signal strength, according to case-mate, which says the devices have been tested in laboratories certified by the FCC. The cases will be available in a variety of colors this fall for $49.99. An earlier version of the cases for iPhone 3G/3GS is available now on the case-mate.com.