Onalaska police are asking anyone who witnessed a man’s fall last week on a downtown street to help them figure out how it happened.  Forty-one-year-old Charles J. Wolowicz Junior fell and hit his head at about midnight last Friday.  Emergency responders treated him for a head injury and transported him to a hospital, but he died five days later.  The La Crosse County Medical Examiner’s Office conducted an autopsy Thursday but the final results haven’t been released.