Des Moines Register Professor to speak on effects of media Douglas Gentile, a psychology professor who runs the media research lab at Iowa State University, will speak about the effects of media exposure on youth and families in two sessions at Holy Trinity Lutheran Church, 517 S.W. Des Moines St. in Ankeny. The first session will be at 6:30 p.m. today. It's for youth ages 9 and up, and their parents. The second session will be at 9 a.m. Saturday and is for parents of preschoolers. For information, call 964-4348.