A method of age verification for electronic media. In the open mode, a locking strip of the scalpel handle resides in one opening of the sheath to keep the sheath substantially immobile during use of the scalpel blade. The invention additionally relates to a process for preparing chiral carboxylic acids from the racemic nitriles. The error correction value is used to correct an adjustable power control signal that controls the power level of the power amplifier circuit for a subsequent transmit burst at the same power level. On a semiconductor structure, in depressions on the surface, in particular below the first metal structure plane, a diffusion barrier layer is deposited, preferably with the aid of plasma-enhanced vapor phase deposition, during which the ions contained in the plasma are accelerated perpendicularly to the surface, resulting in non-conformal deposition of the diffusion barrier layer.