for iranians imprisoned in the united states. ahmadinejad said in a television interview today that talks are under way for a possible exchange. the families of the three americans who could be facing espionage charges say they accidentally crossed the border during a hike back in july. hundreds of iraqis are mourning the loss of more than 50 people killed in yesterday's suicide bombing near baghdad. yesterday's blast came in the midst of a shiite pilgrimage this week toward the city of karbala to mark the death of a renowned shiite figure. despite promising heightened security for the pilgrims, iraqi security forces were unable to prevent yesterday's attack. and the medical journal the lancet is retracting a controversial 1998 study linking certain vaccines to autism. the lead author of the study was dead ceted by the it general council in britain calling it biased and his conduct