A 52-year-old Mosier woman was killed Sunday morning when she was hit by a pickup truck while riding a bicycle along Interstate 84.  The Oregon State Police says Ellen Dittebrandt was westbound and approaching the Viento State Park off ramp when the pickup driven by 55-year-old John Allman of Portland traveled onto the shoulder and struck the bicycle from behind.  Dittebrandt…who was wearing a helmet…was pronounced deceased at the scene.  She was a local artist and Mosier firefighter and emergency medical technician…having been named Mosier’s firefighter of the year in 2010.  Allman was not injured and is cooperating with the Oregon State Police in the investigation.  The OSP indicated driver fatigue has been identified as a contributing factor.  The completed investigation will be forwarded to the Hood River County District Attorney’s Office for review.  The westbound lanes of I-84 were closed for about 90 minutes Sunday morning due to the accident.