All those types of questions are detailed on the CD in my signature, I hate to be plugging my stuff here, but you can find out a lot of that information as well as much better information as it includes a ton of very technical and reviewed articles so that you get the "100% truth", or at least as close as your going to come....instead of a ton of "he said she said" stuff. Anyhow, if you're interested, follow the link in my sig.

-Nathan