41.   In his own lab, Miczek of Tufts has done painstaking experiments on rats in which he can track the flow of serotonin during a bout of fighting.

42.   Joshua D. Baron, a curriculum specialist at Stevens, has put together Internet packages that help instructors do experiments about genetics, volcanoes or tides and waves.

43.   Kador goes on to suggest that you might do that experiment before you even ask the question.

44.   Lab experiments are done to determine the potential benefit or risk of a substance.

45.   More important, economics is for the most part not the kind of discipline in which you can do an experiment that settles an issue beyond all dispute.

46.   Medawar, of course, knew nothing of T cells and had only an inkling of MHC at the time he did those experiments.

47.   Or it might be used to hire a research assistant to help get experiments done, Shore says.

48.   Other scientists say that the company needs to do more experiments to prove that gene integration is indeed happening through transposition.

49.   Related experiments have been done in a vapor of rubidium atoms, Leonhardt said.

50.   Q. Any regrets about doing the experiment?