A computer-implemented method for displaying soft keyboards at a portable electronic device with a touch screen display is disclosed. This approach involves luminescent labeling of the receptor of interest and the automated measurement of receptor internalization to a perinuclear location. The detection circuit is independent of any input or internal signal of the CMOS circuit to be controlled. The regeneration zone allows regenerating air to pass through the dehumidifying member to regenerate the dehumidifying member. A method of validating a secure tag is also described. The apparatus includes partitions for retaining particles, with apertures disposed within the partitions.