Just over a hundred years ago, in "advanced" Western societies, half the live births did not attain the age of 5 years. The engineering wisdom that "you can't change one thing" would seem to apply. We've changed everything... And, many of our modern "epidemics" may well be epidemics of diagnosis... Jack --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .