Described are nucleic acid vaccines containing genes to protect animals or humans against rickettsial diseases. A request for an allocation of an amount of the air-interface resource is received. One or more cutting structures are coupled to the drill tubular above the drill bit. Also provided is a device that includes a data output driver portion configured to drive an output signal at a common mode voltage and a data output driver portion configured to drive an output signal at a differential voltage level during at least a portion of time when the device is not in a low power state. Therefore, because a torque load of a respective clutch is reduced, durability may be enhanced and a length of the transmission may be minimized.