And there seems to be no shortage of work. A major Serra sculpture composed of four walk-through spherical sections was installed in a prominent position at the Toronto airport about six months ago, but it won't go on view until construction of the terminal is finished. The UC San Francisco Medical Center's new Mission Bay campus also has a Serra awaiting public unveiling. Seizing an opportunity to honor a native son, Chancellor J. Michael Bishop spearheaded a drive to acquire a Serra for the main pedestrian entrance to the campus. It consists of two 60-foot-tall steel plates placed about 300 feet apart.