Abstract: A surgical port includes an end face comprising a channel extending through the end face, the channel having a cross section shaped to receive a surgical instrument cannula, and a lateral wall extending around a perimeter of the end face, the lateral wall and end face enclosing an open volume. An end portion of a wound retractor is received in the open volume of the surgical port and in engagement with an inner surface of the lateral wall, and the surgical port is configured to abut a body wall in an inserted position of the wound retractor through the body wall.

Abstract: A dynamic arbitration system for controlling the data transfer between primary and secondary buses in a personal computer has master and target components on both buses. Primary and secondary bus arbiters are included in a bridge circuit, and initially operate independently of one another in a concurrent arbitration mode of operation. This avoids primary bus interruption for secondary-to-secondary transfers and optimizes the primary bus bandwidth. Whenever a secondary-to-primary bus data transfer cycle is detected, the bridge circuit switches the primary and secondary bus arbiters to an interlocked mode of operation. The interlocked arbitration mode of operation is maintained until the next secondary-to-secondary cycle is detected; whereupon the bridge circuit causes the primary and secondary bus arbiters to be switched back to the concurrent arbitration mode of operation.

Abstract: A rectangular antenna has a T-bar of planar cross section for providing a axial to cavity transition. A narrow slot having a length equal to one half the wavelength of the upper end point of the frequency range utilized is centered within the T-bar. Tuning stubs are located in predetermined positions directly under the T-bar for reducing the effect of the TE.sub.30 mode.