The invention recites a plasma-arc spray gun comprising a cathode and an anode defining a longitudinal axis. According to the method, an electric shutter value and an analog gain control value can be calculated through a proportional integral control method according to a brightness value of an inputted image frame. Upon creation of a hard disk drive password on a system having an administrative password, the hard disk drive password is saved to the hard disk drive and to the BIOS with access from the BIOS restricted by the administrative password. During the odd clock periods, the first part data are filtered and decimated in frequency. The method includes winding the wire onto the toroidal core in a fixed winding plane, rotating the toroidal core during winding, the rotating being about an axis that is perpendicular to a plane of the ring shape of the magazine, and holding the toroidal core using a gripper that moves with the toroidal core during winding. The resulting angled injection pathway improves the retention of the agent in the body cavity wall, while keeping a distal section of the catheter substantially perpendicular to the body cavity wall for optimal push against the tissue at the injection site.