The invention relates to substituted pyrazinoylguanidine compounds. A database of font size changes made by a user to particular documents is maintained and used to infer a font size preference for a document. Metadata associated with the write request may be stored. Each formatted image may be overlaid or placed onto a presentation instrument to personalize each presentation instrument and each presentation instrument may be associated with account information corresponding to the image overlaid or placed on the presentation instrument. Upon sensing a shock, each trigger control path can power a power hold element that provides temporary power to the trigger control paths long enough to process the shock signals and generate any necessary trigger signals.