In a semiconductor optical device, the first conductive type semiconductor region includes a first semiconductor portion and a second semiconductor portion. A second device in the network receives a first message having information relating to a first device in the network. Components including a main circuit contact, a contact switching mechanism, an operation handle, an overcurrent tripping device, an earth leakage detection circuit combined with a zero-phase current transformer, and an earth leakage tripping device, are retained in the main body housing. If more than one sector encompasses the location, the base station may further select as the active set a subset of one or more sectors to which the mobile station is closest. Corresponding electrophotographic apparatuses and imaging methods are described. Also provided are processes for producing such antibodies.