A curable composition to be used for a printed wiring board is disclosed, which has an excellent flexibility and an excellent adhesive property with respect to both a plastic substrate and a conductive layer in the printed wiring board. A ring-shaped wire cage is disposed radially outwardly of the vanes and has one axial end rigidly affixed to the nozzle ring and an opposite axial end rigidly affixed to the nozzle portion so as to fix a spacing between the nozzle ring and the nozzle portion in an axial direction of the variable-vane assembly. adding a prion-specific antibody and detecting binding of the antibody to the sample.