scientific american - 1996 05 - the comets'' lair

scientific american - 1996 05 - the comets' lair

... Among the most com-mon mines in this group are the Italianscatterable mines TS-50 and SB-33 and the hand-laid VS-50 and VAR-40, the U.S made M14, and the Chinese Type72. Typically, these weapons ... Space Adminis-tration unveiled the X-36 the ﬁrst high-performance jet withno tail at all. Remotely controlled and powered by a cruise-mis-sile engine, the 5.4-meter-long, 600-kilogramscale ... case. The type of mine, the speciﬁcs of itsoperation, its position on the ground, the position of the victim and the char-acteristics of the environment at the ex-plosion site all affect the...

scientific american - 1996 01 - the diet - aging connection

... OGDENCopyright 1995 Scientific American, Inc. SCIENTIFIC AMERICAN January 1996 31easily destroyed. Moreover, some theo-rists raised certain technical objec-tions, namely, that the release of a pho-ton ... transform their experiment into the quantum eraser, the researcherstagged one of the photons of the pair(speciÞcally, the one created by the la-serÕs direct passage through the crys-tal). That ... developed coun-tries, many of which are strug-gling to electrify. The panel, as-sembled by the American NuclearSociety, also chided the U.S. gov-ernment for halting its breeder re-search. Then,...

scientific american - 1996 06 - the space station

... the impact of urban agriculture con-tinues to broaden, the notion of the gar-den city the turn-of -the- century dreamof urban centers lined with trees and or-namental plants—may take on a new ... datafrom the probe’s 57-min-ute descent did not chal-lenge the prevailing hy-pothesis of the evolutionof the solar system and itslargest planet, according to RichardYoung of the National ... elemental abun-dances (or the lack thereof), measure-ments of the brisk Jovian winds havepermitted slightly more conclusive the- ories about the planet’s meteorology. Be-fore the probe plunged,...

scientific american - 1996 08 - the electronic wallet

... users of conven-tional cellular phones.SAMICHAEL GOODMANCopyright 1996 Scientific American, Inc. The Stellar Dynamo46 Scientific American August 1996 Copyright 1996 Scientific American, Inc. ... nature show at the Web site whose address the produc-News and Analysis30 Scientific American August 1996 CYBER VIEW The Notworking ComputerDAVID SUTERCopyright 1996 Scientific American, Inc.ers ... to e-mail ad-dresses—fax to the number, and the document, including graphics and signa-tures, will appear in the recipient’s e-mail in-box. Received as a compressedgraphic bit-map file, the...

scientific american - 1996 11 - the origins of immunity

... protected under the executive order’s “state-of -the- art” tech-nology exemption to the bulk declassi - cation rule. But that introduces anotherconcern. The issue is, what does state-of -the- art technology ... risk factors may affect the expres-sion of the disorder,” the group con-cludes in the Journal of the American Medical Association. The lead author of the study, the larg-est of its kind ever ... psychology at the University of Liverpool,and other academics haverufﬂed a few well-groomedfeathers in the staid linguis-tics community. Their gos-sip-grooming hypothesis as-serts that our...

scientific american - 1997 05 - the 100 - year weather forecast

... though, the mothers bring them out into the open to join the rest of the pride. If anyof the other females have cubs, theyform a crèche and remain in near-con-stant association for the next year ... offered to them, somehome owners will balk at the idea ofselling their excess electricity at a dis-count to the local utility, which then re-sells the power for several times the price. The biggest ... of other males.Male lions display their greatest ca-pacity for teamwork while ousting in-vaders the situation that presents the greatest threat to their common self-in-terest. At night the...

scientific american - 2004 05 - the time before time

... disrupting the signals between neurons. COPYRIGHT 2004 SCIENTIFIC AMERICAN, INC.28 SCIENTIFIC AMERICAN MAY 2004In the 18 years since they were dis-covered, high-temperature supercon-ductors ... whatremains of the mess left by the Exxon Valdez. The oil compo-nents are poisoning the otters.COPYRIGHT 2004 SCIENTIFIC AMERICAN, INC.www.sciam.com SCIENTIFIC AMERICAN 31with a dilemma: remove the ... smooth-ly. Therefore, researchers have reexam-ined the reasoning that led them to infera singularity. One of the assumptions—that relativ-ity theory is always valid—is question-56 SCIENTIFIC...

scientific american - 1995 05 - what found the top quark

... inhibitcandor when they are posed the ques-tion, ÒHow big is the diÝerence?Ó (Fur-ther, the work has not yet been peer-re-viewed or published, so the team re-mains quite cautious about the details.)Essentially ... DNA, the ruthenium-ribose combination revealedsomething extraordinary. The researchers examined the electri-cal properties of short lengths of dou-ble-helix DNA in which there was aruthenium ... small and medi-um-size businesses.Until the early 1990s, the World Bankignored the economic signiÞcance ofthese events or dismissed them as irrel-evant. At the same time, however, the historical...

scientific american - 1996 12 - traces of the big bang

... UtahCopyright 1996 Scientific American, Inc.The turn-of -the- century stonebuilding is rotting inside, ﬂoor-boards dusty and dilapidated,pigeons roosting in the eaves. There areno windows in the moldy ... leishmani-asis is being conducted, and the “pep-tideria,” where the synthesized peptidesthat form the basis of the malaria vac-cine are stored. He also points out myr-iad other labs and the entrance ... Princeton Uni-versity who served on a panel that re-viewed the security implications of the NIF for the Department of Energy. Al-though the panel members had con-cerns about the facility, they did...

scientific american - 2001 05 - get the idea (tomorrow's web will)

... Biológica of Doñana-CSIC. At night, the animals leave the safety of the scrubs tohunt on the open lands and ﬁnd themselves at the mercy of hounds unleashed by the poach-ers during their nocturnal ... badgersbelonged to the ﬁve territories in Coto delRey; the others resided within the core of the park, Reserve Biológica. Of the tagged bad-gers, the team recorded 13 deaths, attribut-able mainly to the ... magnitude of the P-T extinction, the impact would have had tobe far larger than the K-T impact.”Becker points out that if an object the sizeof the K-T impactor hit the deep ocean ratherthan...

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