The invention relates to a method of checking the operativeness of a transmission link. The invention also provides expression vectors, host cells, agonists, antibodies, and antagonists. The air-to-refrigerant heat exchanger gives off heat to the indoor air and in the process further cools the refrigerant flowing to an expansion device to thereby increase the cooling effect provided by an evaporator to the refrigeration area. The stapling apparatus further substantially reduces or prevents knife cut line bleeding by energizing a knife blade for cauterizing tissue while it is being cut. Then the probe station is mated to the first tester to test the first subset of wafers.