Abstract: The invention relates to an enzyme electrode which can be sterilized and regenerated and which has a sensitive surface and an enzyme in contact therewith. A semipermeable membrane is arranged at a distance from the sensitive surface of the detecting electrode and defines a chamber containing the enzyme which is supplied to and discharged from the chamber through a supply conduit and a discharge conduit, respectively. A sterilization device for the enzyme is arranged in the supply conduit for the enzyme. The enzyme electrode is produced by means of the detecting electrode being sterilized in a manner known per se and by means of the enzyme being led into a chamber via a sterilization device through a supply conduit for contact with the sensitive surface of the detecting electrode and for contact with the semipermeable membrane arranged at a distance from said sensitive surface.

Abstract: A device for modifying an analog electric signal and producing a modified analog electric signal being a pre-selectable non-linear function of the first signal comprises a plurality of amplifiers having individually variable gains. All amplifiers, possibly with exception for one amplifier, have their inputs connected to an input terminal for the signal to be modified through associated threshold circuits having individually variable threshold values, so that each amplifier operates only when the signal to be modified exceeds the threshold value of the associated threshold circuit and then provides an output signal proportional to the portion of the signal to be modified which lies above said threshold value. The output signals of the amplifiers operating at a given instant are combined into a combined signal constituting the desired modified analog signal.