Thermally responsive walls can be formed of wall panels made from different materials and having staggered conduits with respect to each other when coupled together to form a wall at one temperature. The data processing system includes a plurality of processors, a cache memory shared by the plurality of processors, in which memory a cache line is divided into a plurality of partial writable regions. Both the brush and mill element have features that facilitate their coupling to the motor. A surgical lighthead is similarly connected with the voice recognition system and is responsive to a second set of the command output signals to initiate selected surgical lighthead operations. A stator is positioned at the bearing, and a rotor installed around the stator so as to be rotatable, and is partially inserted into the polygon mirror by insert molding. An exhaust gas temperature sensor for detecting a temperature of an exhaust gas emitted directly from the engine is provided.