A device for supporting at least one arm of an operating person during a surgical or medical operation comprises at least one supporting element for supporting the at least one arm of the operating person, the supporting element being arranged at a carrying structure for carrying the at least one supporting element. A method for forming a semiconductor device includes providing a carrier, applying the solder system to the carrier, coupling the terminal to the carrier via the solder system, melting the solder system to attach the terminal to the carrier and form a completed semiconductor device, and determining if the completed semiconductor device has a different predetermined property from the solder system. The machine comprises a substantially horizontal frame having a fore end and an aft end, a seat moveably mounted on the frame, foot rest means for positioning the user’s feet, a flywheel, a pair of outriggers mounted to the frame and extending laterally from said frame. Various methods for making suitable luminescent nanofiber mats include: electrospinning a polymer solution including or not including the stimulable particles and forming from the electrospun solution nanofibers having an average fiber diameter between 100 and 2000 nm. Moreover, the first display provides backup should the second display fail, and the first sensor provides backup to the second sensor in event the second sensor fails.