A cleaning product is provided that comprises a reservoir and a cleaning pad configured to clean a surface. During operation, a target electromagnetic signal radiating from the computer system is monitored. On top of the substrate, the GaN-based LED contains an n-type contact layer made of an n-type GaN-based material. In one example, the remainder may be calculated with the aid of a remainder table. A positive feedback circuit is constituted by feeding back an output of the emitter follower circuit to an emitter circuit of the first transistor and a negative feedback circuit is constituted by feeding back an output terminal to a base circuit of the first transistor. Preferred methods of the invention include treatment to inhibit the mitcohondrial inner membrane anion channel.