New Orleans Urges People to Take Shelter NEW ORLEANS - With 135-mph Hurricane Ivan closing in with frightening intensity, this flood-prone city scrambled Wednesday to get people out of harm's way, putting the frail and elderly in the cavernous Louisiana Superdome and urging others to move to higher floors in tall buildings.    Ivan made a slight turn north on a path that could bring it ashore early Thursday at the Alabama-Mississippi line, near Mobile, Ala., but forecasters said everyone from New Orleans to the Panhandle should be worried...