Word: materiallize
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Dates: during 1980-1989
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Although the agents of all these infections remained a mystery, the first safe vaccine against a viral disease was developed in the 18th century by Edward Jenner, a doctor in rural England. Jenner noticed that farmhands who contracted cowpox, a mild disease related to smallpox, did not develop the more...
One clue to the activity of viruses emerged during World War I, when a British and a French scientist independently noticed the appearance of clear circular spots in laboratory cultures grown over with bacteria. When material from a clear spot was applied to a different location in the bacteria culture...
Some viruses, like the ones that cause the common cold, look vaguely like soccer balls: round with a surface of bumpy triangular facets. Others, particularly the larger bacteriophages, resemble lunar landing modules. The flu virus looks like the head of a Roman mace, with spikes protruding in all directions; herpes...
Some DNA viruses become inactive and escape detection by the host's immune system by insinuating their genetic material into the DNA of the host cell. A retrovirus, however, must first use its enzyme called reverse transcriptase to convert its RNA into a DNA molecule, which can then insert itself...
Nonetheless, even Middle Americans whose salaries put them squarely in the middle class feel they are slipping below a comfortable standard of living. The material rewards that Middle Americans had begun to take for granted -- a house, vacations, college for the children -- have become more difficult to obtain. The heyday...