Analogs of combretastatin have been discovered which demonstrate impressive cytotoxicity as well as a remarkable ability to inhibit tubulin polymerization. Each link performs an acquisition routine in which its light beam is swept through a pre-defined pattern while transmitting its beam alignment information. A sensor is mounted on the vehicle and is communicatively coupled to the processor. In addition, the switch includes a mechanical element which co-operates with the control lever when the lock is closed, such that the switch indicates that the lock is closed only when the tooth of the retaining pawl co-operates with the second locking notch of the bolt. In the first embodiment, a rotation direction of a reversible motor is changed to a reverse direction which corresponds to an open direction of the lid to drive the lid toward the open direction in response to the output of the locked state detection signal.