A method uses a set of reference symbols. The optical module has a circuit board, a photodetector and a lens stage. A bispecific antibody is used to mediate the binding of RBCs to the exposed subendothelial surface, the bispecific antibody having a first antigen binding site directed against an RBC surface marker and a second antigen binding site directed against a subendothelial epitope. The first lower metal layer is thicker than the second lower metal layer, and the atomic density of the metallic element contained in the first gate dielectric is lower than the atomic density of the metallic element contained in the second gate dielectric. The at least one removable barcode is placed on the at least one other person’s tag to indicate relationship information between the person and the at least one other person.