An expansion enclosure allows additional expansion cards to be used with a computer system. The storage unit stores examination schedule data of the X-ray computed tomography. The grooves are at the same depth and discontinuous at their intersections. The application server determines whether to bypass the received media from entry into a de-jitter buffer based at least in part on the determined number, wherein the de-jitter buffer is configured to queue media from session participants for mixing by the application server during the group communication session. The power for driving the wheels may be provided manually by means of a crank for turning one or the other of the shafts or by an electric motor coupled one of the shafts. In a second method, a line having a gap therein is formed in an interlayer dielectric layer.