Letters.Prime example In "Great computations" (SN: 3/4/00, p. 152), you state, "The first Fermat number In mathematics, a Fermat number, named after Pierre de Fermat who first studied them, is a positive integer of the form where n is a nonnegative integer. is [2.sup.2]+1, or 5," and later, "the first four Fermat numbers are prime, but [among] the rest, up to and now including the 24th, none are prime." Almost all number theorists consider the first Fermat prime to be [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII ASCII or American Standard Code for Information Interchange, a set of codes used to represent letters, numbers, a few symbols, and control characters. Originally designed for teletype operations, it has found wide application in computers. ], so that the first five Fermat numbers are prime. Solomon W. Golomb Solomon Wolf Golomb (b. 1932 in Baltimore, Maryland) is a mathematician and engineer, a professor of electrical engineering at the University of Southern California best known to the general public and fans of mathematical games as the inventor of polyominoes, the inspiration for University of Southern California The U.S. News & World Report ranked USC 27th among all universities in the United States in its 2008 ranking of "America's Best Colleges", also designating it as one of the "most selective universities" for admitting 8,634 of the almost 34,000 who applied for freshman admission Los Angeles, Calif. Another side of depression As many wives of depressed men will tell you, depressed husbands don't just mope around Verb 1. mope around - move around slowly and aimlessly mope move - move so as to change position, perform a nontranslational motion; "He moved his hand slightly to the right" ("Tough talk for depressed husbands," SN: 3/11/00, p. 171). They are often angry, upset, unpredictable, and short-tempered. Kind words are often followed by angry words and periods of self-pity. The wife lives in a minefield and often finds it difficult to believe or accept positive comments. There is very little support for the wives of depressed men. Comments by Johnson and Jacob don't really get to the core of the situation. Ann Robbins Merrick, N.Y. Speak out Hickling and Lee, whose work was described in the article "When ants squeak" (SN: 2/5/00, p. 92), might consider a piezoelectric crystal piezoelectric crystal Cardiac pacing A crystal that produces electrical signals when subjected to mechanical deformation; in pacing, PC sensors are used to detect motion, changes in pressure, etc, in certain rate-responsive pacemakers as a point-source speaker. One would need to figure out a proper coupling-to-substrate scheme to separate the acoustic and substrate vibrational pathways. Yves Kraus Mansfield Center, Conn. Signal intensity We've seen many expositions about the risk and danger of radiofrequency emissions from cell-phone antennae ("Researchers probe cell-phone effects," SN: 2/12/00, p. 100). As a bystander by·stand·er n. A person who is present at an event without participating in it. bystander Noun a person present but not involved; onlooker; spectator Noun 1. to the whole issue, I don't understand why the manufacturers don't design the phones so the antenna comes out by the mouthpiece. First, it would be a more natural location for grabbing and extending, and second, it would put the antenna out in front of the face instead of alongside the head. Jeff Struck Fergus Falls, Minn. Okay, so there seem to be some effects, negative and positive, of using these devices, but so much more needs to be known. How much use leads to various effects, and how do the many confounding confounding when the effects of two, or more, processes on results cannot be separated, the results are said to be confounded, a cause of bias in disease studies. confounding factor factors enter the equation? The preliminary research done in Sweden is an example of what we don't need right now: uncontrolled studies. Occupational stress and ergonomic issues must be controlled or else conclusions about the casual role of phone use in producing headaches and other complaints are useless. Marc Bekoff Boulder, Colo. Send communications to: Editor, SCIENCE NEWS 1719 N Street, N.W. Washington, DC 20036 or scinews@sciserv.org All letters subject to editing. |
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