A Ti\u2014Ni\u2014Nb alloy device is provided which is a shape memory device excellent in response characteristics. The host device includes transmission means for transmitting, to the external connection device, a parameter and an operation control command indicating a command for performing operation control of the external connection device. To meet this need, a facile synthetic procedure for preparation of a biodegradable polymer-coated nanoceria is disclosed; the preferred biodegradable polymer is dextran. In general, the delay matching circuit may include a propagation gate multiplexer have a particular configuration. An image pickup light path defined between the shutter and the image pickup element is sealed by a sealing member.