Systems and methods for locating the shooter of supersonic projectiles are described. The main body includes a restriction portion. The display is movably coupled to the keyboard and the display covers a portion of the keyboard in a closed position and substantially uncovers the keyboard in an open position. The timing at which the lyrics are reproduced is determined by relative time data \u0394T added to the lyric data, so that the lyrics are displayed at right positions corresponding to bar and beat positions. Finally, the present invention provides means for inducing or preventingrescuing apoptosis in a host, which include aquatic and vertebrate.