A Mach-Zehnder Modulator pulse generator is provided having an increased power output. The reference layer includes at least two magnetic domains and a magnetic domain wall between the at least two magnetic domains. The affinity of hepcidin for the HBD peptide permits a rapid, sensitive assay of hepcidin in biological fluids. Multiple collisions between adjacent systems operating on the same wavelength are avoided and the receiver is controlled to consume power only around the timing of the data bursts. The agent unit executes a program including a process of determining a control precondition, a step of calculating an instructed distance or a target distance to an instructed position, and a process of guarding by environmental information. The removable fittings each include an orifice for entry of water to be carbonated into the carbonator.