A sanitary insert includes a housing and a flow guide, the housing having a generally cylindrical shape and an inner wall portion thereof has a concavity around its periphery. A retro-reflector is placed at the end of this hollow structure to send the light back through the waveguide where the light is detected at the same end as the light source. This invention provides an isolated nucleic acid which encodes yeast ACAT-Related Enzyme 2 Required for Viability protein, wherein the encoded ARV1 protein has the amino acid sequence set forth in FIG. It can permit multiple learning institutions to participate, with governance and control afforded to each university according to agreed upon guidelines. The compensation section modifies the command signal according to a current voltage level of the dc power source to control the dead zone, thereby preventing deformation of ac output power of the bridge circuit.