The core metal of a protein such as ferritin is used as a nucleus for crystallizing a silicone thin film and then the thus crystallized film is employed in the channel part of a thin-film transistor. A halftone value in a printed image on the printing substrate is adjusted to a desired value by modifying a halftone dot size. When a customer desires to conduct a transaction using the fuel dispenser, the fuel dispenser transmits select information to the customer’s cellular telephone using this communications link. The powder falls into a grid reservoir below that holds the pieces of the case end lets only the powder pass through.