A multi-user camera control system with automatic tracking capability for use in video conferencing and similar applications includes a plurality of personal controllers, one for each person utilizing the system. The membrane of the present invention comprises appropriate microtopography and surface chemical modifications to facilitate the production of adherent and oriented cells that phenotypically resemble cells in vivo. Two modes of data recovery are provided: \u201cfast\u201d recovery and \u201cundo-able\u201d recovery. The creditor can then add their references to the message and send it to effect the transaction.