Methods for detecting acetylcholinesterase in a brain of a patient, comprising administering to the patient a detectable amount of a radiolabeled compound of a class of benzisoxazoles or a pharmaceutically acceptable salt thereof, are disclosed herein. The traveling wave electrode structure has one signal electrode and two earth electrodes that are disposed sandwiching the signal electrode or one earth electrode that is disposed pairing with the signal electrode, at least the signal electrode of the traveling wave electrode structure is of a material that has a specific resistivity of 2. A lid sterilization apparatus comprises a handle, a column coupled to the handle, a horizontal arm perpendicularly coupled to the column, a mounting arm coupled to the horizontal arm, and a number of fingers coupled to the mounting arm to retain a number of canning lids between the fingers.