The present invention discloses a method and a system for implementing communications between multiple subnets covered by one physical Mobile Switching Center and an MSC. One such method is implemented for optical stimulation of a cell expressing a NpHR ion pump. In another embodiment, two co-axial Cassegrain-type objectives are provided one within the other with a common focal plane array, which therefore detects combined wide field-of-view and narrow field-of-view images. The data aggregator includes a discriminator for classifying features, a merger, unmerger, converter, and evaluator. A contact area between the seat part and the seat of the valve body has a first outer diameter.