A food support element, such as a shelf, drawer or the like, for removable insertion into a refrigeration compartment of a refrigerator having differential temperature zones, the temperature in the zone overlying the support element being set and controlled by a known control device provided with setting and control means associated with the element. The method and apparatus addresses both limiting access to the computer network to those who are authorized to have access as well as the privacy of the information stored in the network. Impurity elements present in the substrate to be analyzed are identified based on the measured characteristic X-ray. The charge connector converts the charge power source into a form suitable for charging up a cellular phone. By monitoring the overshoot voltage and automatically compensating for it in real-time, a knowledge of a value of the propagation delay is not needed. A method of operating the memory cell is provided.