BOSTON (AP) — Lawyers for a Massachusetts man charged with conspiring to help al-Qaida have lost a bid to bar federal prosecutors from showing jurors gruesome videos of the World Trade Center burning after the Sept. 11 terrorist attacks and the beheadings of Americans.Tarek Mehanna's (THE'-rek meh-HAH'-nahz) lawyers argued that showing the videos would shock jurors and be unfair to Mehanna. The Boston Globe reports ( Judge George O'Toole Jr. denied the motion Monday and twice denied a defense request for a mistrial.Prosecutors say that after Mehanna made an unsuccessful trip to Yemen to try to get training at a terrorist camp, he returned home to Sudbury and began helping al-Qaida by translating and distributing online texts and videos promoting violent jihad.Mehanna's lawyers say he went to Yemen for religious study and his online activities are protected free speech.___Information from: The Boston Globe,