A compressor hub assembly may include a hub member, a valve retainer and a valve member. Programming of the calendar is operable so that when someone at one of the electronic devices alters a calendar item, an animation corresponding to such alteration is displayed on the calendar displayed at another one of the electronic devices. the increase of critical current densities, of bicrystalline or polycrystalline superconductor structures, especially of high-Tc superconductors. Client andor server IP addresses may be clustered in accordance with the teachings herein.