In a client-server architecture, a semi-persistent connection between the client and the server allows delayed or asynchronous transmission of a cookie or token. The first receptor of the invention, Tango-63d, encodes a 440 amino acid polypeptide and the second receptor of the invention, Tango-63e, encodes a 411 amino acid polypeptide. A first circuit on the system board may detect the presence of a graphics card in the expansion slot automatically after powering up the system board. The sets of overlapping holes are adapted to receive a bone screw with a head and a bone-engaging thread. The second film of the second device structure is etched to define an under-cut space between the first and second films.