The present invention describes a masking agent for food products containing polyunsaturated fatty acids. A visited mobile switching center registers a wireless unit that is roaming in the visited system, but denies originating communication service to the unit. The pixels of each row of the pixel array may be configured to cause an approximately even amount of common voltage loading to be shared between one of a first plurality of common electrodes and one of a second plurality of common electrodes when the pixels of each row of the pixel array receive a scanning signal and a data signal.