The invention relates to the discovery that HNA-3a and HNA-3b are antigens within a polypeptide sequence that is highly similar to the CTL2 amino acid sequence. The method comprises generating for the mobile station a cipher key for use by the mobile station during communication in the second cellular communications system. The use of the material as an absorbent structure in an absorbent product. Non-visible light that has passed through the FPD is reflected from objects adjacent to the display, passes back through the FPD, and is detected within the housing.