(Portland, OR)  --  A man accused of trying to detonate a bomb in downtown Portland is scheduled to spend more than 25 years in federal prison.  Twenty-three-year-old Mohamed Mohamud received a 30-year sentence yesterday, and will be under supervision for life after his release.  Mohamud was given credit for the four years he's been in custody since his arrest.  He tried to detonate a bomb, which turned out to be fake, during a Christmas tree-lighting ceremony in Portland's Pioneer Courthouse Square in 2010.