31.   In three decades, he said, he has seen the understanding of nerve functions grow exponentially, particularly as scientists learn more about the makeup of DNA.

32.   It will be later this week before scientists learn whether spores were present in her home, which investigators tested Tuesday.

33.   John Glenn already is a shining example of what scientists have learned about aging gracefully.

34.   Maybe when scientists learn more about human brains, they will be just as unimpressed by how Kasparov thinks through a game.

35.   Military craft can zoom in on ground targets, letting scientists learn more.

36.   No practical uses of metal hydrogen are feasible until the scientists learn how and if they can keep the hydrogen in metallic form indefinitely.

37.   Now scientists have learned that the bursts may indeed repeat themselves.

38.   Now, new species of such beings are turning up with increasing frequency, and scientists are learning just how crucial their role in marine ecosystems is.

39.   Once the station is fully assembled and running, scientists may learn more about how astronauts react, physically and mentally, to extended periods in space.

40.   Only recently have scientists learned how to keep the animals in captivity, he says.