Word: silk
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...battle prayer, "what brave men must I lose this day?" Adding his own invocation to that of the negotiators in Pans to still the guns, the President last week paid homage to four heroes of Viet Nam in a unique Pentagon ceremony, hanging the star-spangled blue silk ribbon and bronze star of the Medal of Honor around the necks of a soldier, a sailor, a Marine and an Air Force pilot. >Army Specialist Five Charles C. Hagemeister, 21, has the kind of bravery that often prompts Viet Cong snipers to single out the aid man as he moves...
...research he found that different species of moths had various means of escaping from their cocoons. He found that, for example, one Australian species has a hard, pointed structure at the front of its head that it uses as a saw and that the caterpillar of one kind of silk moth leaves an exit hole when it builds the cocoon. The species Kafatos chose to work with, the Chinese Oak Silk Moth, however, had no such obvious method...
...soon found that the moth opens its cocoon by wetting it with some kind of liquid that softens the glue holding the silk threads together. Kafatos discovered that a certain drug made the liquid appear on the moths' face, even when they were not trying to escape from a cocoon, and collected the liquid efficiently by applying the drug. After realizing that the liquid must contain some material in addition to salt and water, Kafatos guessed that an enzyme, a chemical agent that helps break down or "digest" other chemicals, was the liquid's active element...
WHILE dissecting pupae in search of the liquid's production site, he noticed a pair of long, very thin tubes in the front part of the pupa. These were the remains of the silk-producing tubes of the caterpillar. They led to a single opening on the moth's face just underneath the mouth. It was impossible to tell exactly where the liquid comes from since the first drop appears suddenly and covers the face. Yet the mouth and the old silk tubes were the only two openings and the mouth could be discounted because Kafatos had already shown that...
...plugged up the silk tubes with melted wax, leaving the mouth open. When the liquid-producing drug was administered, no liquid appeared until the wax was removed. Kafatos was certain that the liquid did come from the tubes. Yet when he mashed the tubes, expecting to find the enzyme, no enzyme was present. One of Kafatos' typical brainstorms saved the day. He realized that the liquid he had been collecting was produced by two glands. The old silk tubes produced the inert part of the liquid while a special gland on the face secreted the enzyme itself. Kafatos substantiated these...