Abstract: A self-directed distributed system provides a method for mutual exclusion of asynchronously interacting processors. The system comprises a system for control of access to a shared resource in a multi-processing computing environment, comprising at least two processors; an interconnection system interconnecting the processors, whereby each processor can communicate with all other processors; a resource for shared access by the processors; communication means within each processor for sending an interest signal to all other processors for signalling the interest of the processor in acquiring the resource; receiving means within each processor for receiving the interest signal of every other processor; interest vector means within each processor for storing the received interest signal of every other processor; and means within each processor for interrogating the interest vector means in the processor to determine the availability of the resource.

Abstract: A system and method for detection of electrical bioimpedance signals in a human or animal body segment. The system comprises a constant current generator for generating a periodic high frequency current output across a body segment in response to a periodic control input signal, a controller for generating a periodic control output signal to control operation of the current generator and an electrical bioimpedance detector for detecting a voltage generated across the body segment by the flow of current in the segment. The electrical bioimpedance detector generates an output signal indicative of bioimpedance in the body segment. The periodic generation of a current across a body segment alleviates the potentially detrimental effects of a continuous current on body segment tissue and reduces interference with the function of certain pacemakers.

Abstract: A system and method for detection of electrical bioimpedance signals in a human or animal body segment. The system comprises a constant current generator for generating a periodic high frequency current output across a body segment in response to a periodic control input signal, a controller for generating a periodic control output signal to control operation of the current generator and an electrical bioimpedance detector for detecting a voltage generated across the body segment by the flow of current in the segment. The electrical bioimpedance detector generates an output signal indicative of bioimpedance in the body segment. The periodic generation of a current across a body segment alleviates the potentially detrimental effects of a continuous current on body segment tissue and reduces interference with the function of certain pacemakers.

Abstract: An improved surgical cutting block for guiding bone saws in joint surgery and similar instruments. The cutting block is provided with one or more cutting guides having cutting guide surfaces positioned on exterior faces of the block or along channels within the block. The cutting guide surface is formed of a material having a Knoop hardness of 466 or greater (under a 500 gm load or greater), a chrome content of less than 10% and a nickel content of less than 4%. According to another aspect of the invention, a method of cutting bone tissue utilizing the improved surgical cutting device is disclosed wherein heat-generated damage to bone tissue is reduced and production of toxic residue is minimized.