The present invention is directed to a method for making a multiple layer substrate comprising the steps of: forming a carrier substrate; depositing an air laid layer comprising natural fibers on top of the carrier substrate; wetting the air laid layer with a source of low pressure water; hydroentangling the air laid layer with the carrier substrate to form an integrated substrate. The CVSs are capable of sensing the presence of an object in at least two different spatial areas and generating area specific signals. The invention also provides thiolester-inactivated viruses and thiolester-complexed viral proteins. A receiver generates a receiving signal by sweeping the receiving frequency of the THz wave within the frequency band.