“The Kennedy Center voted yesterday to appoint Alma Powell and Kenneth Duberstein, the vice chairmen of its board, to oversee the center’s operations while it continues to search for a new chairman. Powell and Duberstein will take over the duties of James A. Johnson, who announced last April that he would step down this month after seven years as chairman… The 32-year-old federally supported arts center has enjoyed an artistic renaissance in recent years.”