For a second time since the government's wide-ranging Rhode Island State House corruption probe began, a federal judge sentenced former Roger Williams Medical Center President Robert A. Urciuoli to three years in prison for buying the legislative influence of a former state senator. In sentencing the former hospital executive, Chief U.S. District Judge Mary M. Lisi acknowledged that the public official at the center of the case, former state Sen. John A. Celona, was "somewhat of a shakedown artist."