Trenches are formed in a base layer and extend parallel to each other. Also provided are methods for chemically analyzing a sample by negative ion atmospheric pressure ionization mass spectrometry by exposing the sample to electrons from a 63Ni ion source in a drift tube and allowing the sample and electrons to react in the drift tube prior to analysis via mass spectrometry. In a typical embodiment, the cardholder approaches a magnetic reader with the card. The architecture can comprise a social network system that includes a database for mapping search-related information to an entity of a social network, and a search component for processing a search query for search results and returning a link to an entity of a social network based on the search query.