scientific american - 2000 07 - alien civilizations if they really exist, why aren''t they here
scientific american - 2000 07 - alien civilizations if they really exist, why aren't they here
... in 1950. If extraterrestrials are commonplace, he asked, where 38 Scientific American July 2000 Where Are They? SEARCHING FOR EXTRATERRESTRIALS Copyright 2000 Scientific American, Inc. Where Are They? ... www.sciam.com ALIEN CIVILIZATIONS If they really exist, why aren’t they here? DEADLY LAKES Exclusive: Preventing a catastrophe in Cameroon THE WHY OF WEIGHT...
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scientific american - 1993 07 - telling resonable risks from fools' chances
... are constant, apparently because they are necessary for HIV to function as a ret- rovirus. They establish that HIV is the SCIENTIFIC AMERICAN July 1993 47 Copyright 1993 Scientific American, Inc. descendant ... been the signiÞcance of the information con- cept to molecular evolution and its tech- nological applications. Copyright 1993 Scientific American, Inc. SCIENTIFIC AMER...
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scientific american - 1994 07 - how cancers defeat drug therapy
... of the Þeldwork be- cause many of the men have off-site jobs. SCIENTIFIC AMERICAN July 1994 35 Copyright 1994 Scientific American, Inc. years ago. A judicious choice of fast- maturing varieties ... that the worldÕs biggest environ- mental release occurred over decades at a site called Tomsk-7 in central Sibe- ria. Tomsk-7, whose existence was clas- 20 SCIENTIFIC AMERICAN July 1994...
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scientific american - 1995 07 - can implants cure diabetes
... Images Copyright 1995 Scientific American, Inc. T he high-temperature supercon- ducting ceramics that amazed physicists when they were discov- ered in 1986 have been amazing mate- rials scientists ... necessary to compare products. What it often fails to do, how- ever, is to translate data-on-a-screen into the understanding-in-a-head need- ed to make a decision. Ultimately the economics...
Ngày tải lên: 12/05/2014, 15:01
scientific american - 1996 07 - hawking vs penrose
... Inc. SA Copyright 1996 Scientific American, Inc. News and Analysis28 Scientific American July 1996 BY THE NUMBERS The Changing Quality of Life T hese maps show the Physical Quality of Life Index ( PQLI), ... on the differing rates of de- News and Analysis Scientific American July 1996 35 PANACEA LOST? Pity the economist who tries to market social insights ECONOMICS Copyright 1996...
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scientific american - 1997 07 - an endangered buddha contemplates oblivion
... Mediterranean. Treasures at Dunhuang Copyright 1997 Scientific American, Inc. ROBERTO OSTI Copyright 1997 Scientific American, Inc. Scientific American Month 1997 1 ROME ALEXANDRIA QUILON BUKHARA HAMADAN GUANGZHOU TYRE BAGHDAD REY MARY SAMARKAND KASHI SHACHE BARBARICUM HOTAN DUNHUANG XI’AN ANXI BEIJING TURPAN ANTIOCH ENCROACHING ... some back-of-the-envelope doodling and created a...
Ngày tải lên: 12/05/2014, 15:28
scientific american - 1998 07 - new victories against hiv
... LABORATORY 43 Scientific American July 1998 Copyright 1998 Scientific American, Inc. The most important requirement for life on Earth (the only kind we know) is liquid water. Under present condi- tions ... REPORT 82 84 88 90 94 96 98 104 106 Copyright 1998 Scientific American, Inc. The Mars Pathfinder Mission 46 Scientific American July 1998 The rocks analyzed by Pathfinder, howe...
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scientific american - 1999 07 - molecules from space
... down- loading music from the Internet in the May issue. News and Analysis Scientific American July 1999 41 CYBER VIEW On-Line U. DAVID SUTER Copyright 1999 Scientific American, Inc. Life’s Far-Flung ... form blood if they are placed in bone marrow. Vescovi says that if other stem cell types can also modify their fates in this sur- prising way “you are looking at a reser- 30 Scie...
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scientific american - 2000 01 - we were not alone only we remain why
... JPL Copyright 1999 Scientific American, Inc. News and Analysis 22 Scientific American January 2000 E ven when humans aren’t doing it, they are likely to be think- ing about it. The representa- tives of ... North American placentals dated to 80 million years, so why aren’t there any placentals from that 30-million-year interval? Cifelli notes that if placentals did arise in North...
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scientific american - 2000 02 - galileo finds fire and brimstone on jupiter's moon io
... Scientific American more in 1999, Einstein or Zorpette? Copyright 2000 Scientific American, Inc. CHAN N ot often does a past geolog- ic event exemplify what the actions of humanity may in- flict on ... of California at Los An- geles, are giving way to more vicious actions, such as booby-trapped mail and arson. JOSEPH SOHM ChromoSohm, Inc./Corbis Copyright 2000 Scientific American, I...
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