This invention provides biphenyl derivatives of formula I: wherein R1, R2, R3, R4, R5, R6, R7, W, a, b and c are as defined in the specification, or a pharmaceutically acceptable salt or solvate or stereoisomer thereof. \u201d Every type of recognized entity has associated action options that populate a node menu for that type. The axial rotor sections are rotationally offset such that the edges of the permanent magnets create stair step interfaces. An alternative embodiment provides an apparatus and a method for a Smart Pass-Through Operation which involves switching between the Simple Pass-Through and the Rate Converter.