A code optimizer is used to optimize a computer program that references a database by determining the characteristics of the database and making suitable optimizations based on the characteristics of the database. In addition, one of the insulating substrates has a plurality of holes formed in the facing surface. The first display is structured and arranged to display a threshold value that may be set by an operator of the photoelectric sensor. Each push bar includes a handle post that can be gripped by a caregiver to push the stretcher. The software development tool builds the at least one business process path based on results of the mapping. The operation is self-limiting in that cells stop their resistance shifts upon reaching the target level.