An apparatus for irradiating an article, particularly a multi-layer article, with electron beam radiation is provided. In some embodiments, a method includes receiving an ambient light sensor output, and altering, based on the ALS output, an effect of a proximity sensor output on control of a proximity determination. The underside of the mouse incorporates a trackball and a recessed numeric keypad. The transport unit transports the display recording medium inserted, tofrom the write position. Some such embodiments further include requesting the source of the lock object invalidate the lock object if the lock object indicates the lock object is valid, receiving an invalidation of the lock object, and performing the update to the record data object.