An engine is described having a camshaft 10 formed of an inner shaft 12 and an outer tube 14 both of which rotate with respective groups of cams 18 and 16. A first circuit node, a second circuit node, and a third circuit node interface the illumination device such that a voltage supplying the plurality of light emitting diodes is applied between the first and the second circuit node and a first fraction of the supply voltage drop is provided between the third and the second circuit node. By recording the navigation path taken by many users, relationships between information assets may be identified. The antennas may be formed from coaxial cable, enabling them to provide electrical connections between the microphone or loudspeaker and transceiver circuitry in the body of the apparatus. The drive turbine wheel may be designed for the drive fluid to axially impinge on the turbine blades. The present invention includes a cryo balloon therapy apparatus, comprising a catheter having a proximal and a distal end, a cooling member disposed at the distal end of the catheter, a pull cord coupled to the cooling member, and a sheath that couples the pull cord and the catheter.