A key switch-replaceable keyboard mounting arrangement. Tissue surfaces and surgical articles involved in the surgery and bioprostheses are coated with a solution of a hydrophilic, polymeric material prior to manipulation of the tissue andor organs during surgery. When the power supply state is not in the first power mode, the basic input output unit executes a second power booting program. In addition, the policy database associated with one virtual machine may be updated and the database lookup associated with the policy database re-generated independently without requiring any update of the policy database lookups associated with any of the other policy databases in the computer system.