Abstract: A fan-in/fan-out device includes a plurality of single-core fibers which are connected to a plurality of first cores of a multicore fiber and which include an elongated portion extending in a longitudinal direction so as to reduce a diameter and being connected to a first end portion of the multicore fiber at a second end portion in an extending direction of the elongated portion, where a refractive index distribution of each of the single-core fibers has a single peak, a relative refractive index difference of a second core with respect to a second cladding in each of the single-core fibers is 0.8% or more; and a second mode field diameter of the second end portion of the elongated portion is greater than a first mode field diameter of the first end portion of the multicore fiber.

Abstract: A method of immunoassay of H5 subtype influenza A virus by which the virus can be accurately assayed even in cases where a certain level of mutation has occurred in the H5 subtype influenza A virus, and a kit therefor, and a novel anti-H5 subtype influenza A virus monoclonal antibody which can be used for the immunoassay are disclosed. The antibody or an antigen-binding fragment thereof of the present invention undergoes antigen-antibody reaction with hemagglutinin of H5 subtype influenza A virus, and the corresponding epitope of the antibody or an antigen-binding fragment thereof is located in a region other than the receptor subdomain (excluding C-terminal region thereof consisting of 11 amino acids), which antibody or an antigen-binding fragment thereof does not have neutralizing activity against the influenza A virus.