Silica-based particles coated with antimony oxide with a low refractive index and having conductivity are provided. The computation circuit may be responsive to the signals to calculate a flow rate for a fluid flowing along the carrier, compare the calculated flow rate to upper and lower limits, and reject the assay result if the calculated flow rate is outside the upper and lower limits. i is the Jitter associated with a virtual link i that represents the time interval between the theoretical instant at which a frame is transmitted, and its effective transmission which may be before or after the theoretical instant. The release mechanism is provided with an actuation means which is able to induce an extrinsic actuation of the intrinsic release mechanism upon receiving a radio signal. An improved growth rate and cell density of cyanobacteria is exhibited. In the magnetic head, magnetic shields exposed on a surface opposite a magnetic recording medium and a flux guide exposed between the magnetic heads via a non-magnetic layer are provided, and magnetic fluxes are guided by the flux guide to a magnetoresistive element formed in a position not exposed on the air bearing surface.