A network task offload apparatus includes an offload circuit and a buffer scheduler. In one embodiment, a fastener-applying device, which is preferably a stapler, is passed transorally into the stomach to plicate stomach tissue by engaging tissue from inside the stomach and drawing it inwardly. A change of transmittance depending on a light path of the projection optical system is measured, based on a pattern image of the diffraction light transferred to the wafer. In addition, the polymer actuator is formed to change a width of the microchannel by controlling a displacement of the valve portion. Neither the customer nor the merchant may be aware that the transactions are being handled by the IOM.