James (Jim) Davis Jul 16, 2009:

Explanation I had posted "compared to the control" with a long explanation, but it got lost in my browser somewhere. I studied experimental psychology, but experimentation techniques are the same across the life sciences (biology, pharmacology) and elsewhere. Basically if you want to see if aspirins relieve pain, you take two groups a test group and a control group. You make both of them listen to a prime minister for five hours and then give them both a pill. One gets aspirin the other gets a placebo. The placebo is the control group, or just the "control". Wiki gives a more technical account:<br><br>http://en.wikipedia.org/wiki/Scientific_control<br><... I forgot, then after ten minutes you look to see which of the two groups is writhing in least pain.

Paul O'Brien (asker) Jul 16, 2009:

yes yeah, lionel, that makes a lot more sense.

Lionel_M (X) Jul 16, 2009:

does this help ? ...reale tossicità acuta del campione rispetto alla naturale tossicità di un materiale detritico o sedimentario di riferimento !

Paul O'Brien (asker) Jul 16, 2009:

control yes, but i don't see that "control" means anything here.