Nitrided valve metals are described, such as nitrided tantalum and nitrided niobium. The two pre-distorted signals are separately amplified and then recombined to generate a linearized amplified output signal having amplitude information. An operating temperature of the first gas detector may be changed to a second operating temperature, or a second gas detector having the second operating temperature may be provided. DNA can be added to the magnetic particles as a means for providing identification to a manufactured component or for identifying one or more characteristics of the component or portion of the component. The therapeutic agent advantageously regenerates nerve cells and blood vessels in peripheral nerve tissues and thus rehabilitates the injured nerve tissues to improve nerve conduction velocity, and relieves pain induced by traumatic peripheral nerve injury.