Techniques, apparatus and systems that use composite left and right handed metamaterial structures to combine and divide electromagnetic signals at multiple frequencies. This determination is made over a certain geographical area for a statistically significant amount of time. In another embodiment, the system can also include an atmospheric-pressure ionization chamber, an atmospheric-pressure ionization sprayer and a nebulizer gas source and a voltage supply source. The second surface of the piezoelectric sensing structure faces the flexible substrate. The head, in a first configuration allows inward flexing to reduce a diameter of the head to allow the head to pass through an entrance opening of the through hole.