A circuit and method protects an emergency head-retract capacitor that regulates initial charge current using a constant current source. In one aspect, a method of polishing a work piece is provided. The baffle plate includes a catalyst receptacle in the first chamber, the second chamber includes the exit of the housing. Cassettes that can operate with the sample analyzers are also described. The controller is further configured to set a correction value for correcting a deviation between a display position of traces and a detection position of a touch input on the touch screen display, by using the first and second positional data.