A food heating device includes a platen and a pair of conveyor segments. This database accelerator holds on an accelerator system copies of location tables, which correspond to primary-key indices, and alternate-key location tables, which correspond to alternate-key indices, for a primary system that performs data updates. A method of treatment of a subject in need thereof using the variable pressure chamber is also provided. The resulting precipitate falls out of solution to the bottom of the body of water for subsequent removal via filtration. The present invention prevents or reduces the likelihood of the potential nonconvergenceclock runaway problem, advantageously with minimal or no changes to existing designs and logic.