A unique HCV RNA molecule is provided having an enhanced efficiency of establishing cell culture replication. In certain embodiments, each of the expanded signals has a different magnitude at a respective fixed offset from the input signal. The visor-like shield plate extends obliquely downward from between the upper edge of the shade and the opening, thus allowing only the reflected light from the lower reflecting area of the reflecting surface to be directed to reach the opening of the shade, and preventing light flux of an overhead sign illuminating light from becoming excessively bright.