Word: electronics
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Dates: during 1940-1949
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...have long believed that the polio virus creeps along the nerves, on its way to destroying the nerve cells. Last week, for the first time, the virus was caught in the act. Drs. Eduard De Rober-tis and Francis Otto Schmidt of M.I.T. showed a Toronto convention of the Electron Microscope Society of America some remarkable pictures of the polio virus marching in orderly files along a nerve fiber...
Last year Drs. De Robertis & Schmidt turned their electron microscope, which is far sharper-sighted than the ordinary "light microscope," on nerve fibers, the delicate tendrils sent out by nerve cells. They found that the fibers were cables made up of many hollow tubes about one-millionth of an inch in diameter. The discovery gave them an idea. The "neuro-tubules" seemed ideally adapted for conducting submicroscopic objects around the body. Perhaps, thought the doctors, they conducted the polio virus on its missions of paralysis and death...
This theory turned out to be true. The doctors proved it conclusively by exposing cut nerve ends of Rhesus monkeys to the virus of human polio. They then separated the slender neurotubules a little way up the nerve and examined them under the electron microscope. Some of them were full of tiny round specks not present in healthy nerves. By extracting the nerve samples at different times, the doctors proved that the particles crept slowly up the nerve from the point of entry. They moved about 2 mm. (1/12 inch) an hour-roughly the rate that polio infection is known...
...current issue of Physics Today, Dr. George Gamow tells why he thinks that neutrinos are as real as electrons or protons. Physicists, he says, invented neutrinos because they needed something to explain why electrons, shot out of the same atomic nuclei under the same conditions, do not all have the same energy. One way to account for this discrepancy is to imagine a very small, uncharged particle that departs at the same time as the electron, carrying with it some of the energy...
Neutrinos are perhaps two-thousandths the mass of an electron, and have no electric charge by which they can be influenced electrically. They pass right through matter as if it weren't there. Physicists have calculated, says Dr. Gamow, that it would take a lead shield 200 million million miles thick to stop speeding neutrinos...