Methods, apparatus and computer programs are provided for determining header data for and based on a plurality of messages. The nonwoven materials are in the form of a fibrous web and the fibers are made up of struts which define open and closed cells. Through this beacon, it is possible to make a sophisticated judgment on the communication state in the other communication station. The positioning mechanism includes an upper curved form and a lower curved form to guide the stack of substrate sheets into a curved position for folding. The method can be performed in plurality simultaneously with fluorescence or absorbance readouts.