A junction for connecting first and second adjacent sections in a guideway carrying pressurized fluid comprises female end portions on a first section, male end portions on a second section partially received within the female end portions, and a vessel. The microporous materials contain a crystallizable propylene-containing polymer, a beta-nucleating agent, and a diluent that is miscible with the polymer at a temperature above the melting temperature of the polymer and that phase separates from the polymer at a temperature below the polymer crystallization temperature. The heater element extends between an end wall of the firing chamber and a baffle plate facing the end wall. If the second zone is more preferable, the first zone is maintained within the second cell until the signal strength of the second cell exceeds the signal strength of the first cell by an amount determined by an exit parameter. While in the lower power consumption mode, processor requests to the processor interface are inhibited. The containers are heated in a vertical orientation to safely heat the food without overheating or damage to the container.