scientific american - 2000 09 - muscles & genes are star athletes born, not made

... OtherEarthsSEPTEMBER 2000 $4.95 www.sciam.com ARE STAR ATHLETES BORN, NOT MADE? Muscles Genes &Brian Lewis, 1999 World Outdoor Gold Medalist Copyright 2000 Scientific American, Inc.Copyright 2000 Scientific ... HAZARDSFive-year-old10-year-oldAdultCELL-PHONE ENERGY penetratesmore deeply into a child’s brain than anadult’s, as shown in these models.Copyright 2000 Scientific American, Inc.Scientiﬁc American ... (est.)N/AH-4AN-225747Copyright 2000 Scientific American, Inc.Technology & Business44 Scientiﬁc American September 2000 will reduce the A3XX’s weight by severaltons. But for now hard facts are...

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scientific american - 2000 03 - what computers are learning from them

... 22ANTI GRAVITYC-A-T-T-T-T-T-T-T-TThe fog comes on little cat feet,”wrote Carl Sandburg. The greatpoet and historian may merely havebeen attempting to animate water va-por, but he presciently ... afﬁrmation was short-lived. The back-to-back failures ofthe next two spacecraft, the $125-million Mars Climate Or-PAT RAWLINGSCopyright 2000 Scientific American, Inc.biter and the $165-million Mars ... system.”Currently the biosensor is a 25-mil-limeter-square plastic chip that has ameandering ﬂow line running through it.One- to two-millimeter-square patches,containing 10,000 B cells engineeredfor...

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scientific american - 1993 09 - special issue - life, death, and the immune system

... SCI-ENTIFIC AMERICAN, 415 Madison Ave-nue, New York, N.Y. 1001 7-1 111, or fax(212) 35 5-0 408.Photocopying rights are hereby grant-ed by Scientific American, Inc., to li-braries and others registered ... diversi-ty springs from the size of these mini-gene families: there are more than 100kinds of V (variable) genes, 12 D (diver-sity) genes and four J (joining) genes. The C, or constant, genes ... complete V-D-J-C gene. This genetic rearrange-ment allows for 4,800 diÝerent vari-eties (100 × 12 × 4 × 1) of heavy chains.The same process occurs in the assem-bly of the light-chain genes, ...

scientific american - 1994 09 - conquering lyme disease

... explains how to cross-reference ICD-IX and ICD-X codes.So why does DSM-IV use codes froman earlier version of ICD? ÒIt may takeanother seven years before ICD-X stan-dards are adopted in this ... health on ICD stan-dards. In some cases, more than oneDSM-IV disorder falls under the sameICD-IX heading. And the ICD-IX num-bers are diÝerent from those used inthe ICD-X, which debuted ... climate, high-en-ergy physicists are beingforced to redeÞne theirgoals. ÒThe SSC had creat-ed a mood of very highexpectations,Ó says JamesD. Bjorken of SLAC. Ex-perimenters are reconcil-ing...

scientific american - 1995 09 - 150th anniversary issue - key technologies for the 21st century

... According to Bird, we are here today for the same reason we pre-fer one stereo system over another: bet-ter signal-to-noise ratio.Assuming that the number of func-tional genes an organism uses ... Black Star ROB NELSON Black Star Copyright 1995 Scientific American, Inc.export of software incorporating en-cryption algorithms with keys of 40bits or less. Not covered by this conces-sion ... CaplanCopyright 1995 Scientific American, Inc.Copyright 1995 Scientific American, Inc.The future is not what it used to be,Ó wrote the poetPaul ValŽry decades ago, and it would not be hard toshare in...

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scientific american - 1996 09 - special issue - what you need to know about cancer

... howev-er, the consuming issues are not statisti-cal and political but personal and med-ical. What are the latest ﬁndings abouthow cancer develops and becomes le-thal? What is the most up-to-date ... Throughmass production, Intel made micropro-cessors affordable, launching the per-sonal-computer industry and a multi-billion-dollar business. Now, 25 yearslater, a small start-up just a few milesfrom ... prepares itself for M (mi-tosis)—the time when the enlarged par-How Cancer Arises Scientific American September 1996 65Some Genes Involved in Human CancersGenes known as proto-oncogenes...

scientific american - 1997 09 - building doors into cells

... thatproduce starbursts are rare in our cos-mic neighborhood. At 10 million light-years distant—about ﬁve times as far asthe Andromeda galaxy—M82 is thenearest major starburst galaxy. But col-lisions ... similar experi-ments did not self-mutilate.That public statement won Moor-Jan-kowski no friends in the medical com-munity. “He has his own ethics,” Telekinotes. “And it certainly does not involvetowing ... GRACECopyright 1997 Scientific American, Inc.In Search of AIDS-Resistance Genes Scientific American September 1997 49blood cells from two of these men indi-cated that the CCR5 protein was ab-sent from...

scientific american - 1998 09 - a last look at laetoli

... Scientific American, Inc.G 1-3 1G 1-3 0G 1-2 9G 1-2 8G 1-2 5G 1-2 6G 1-2 7G 1-3 3G 1-3 4G 1-3 5G 1-3 6G 1-3 7G 1-3 8G 1-3 9G2/ 3-2 2G2/ 3-2 1G2/ 3-1 8G2/ 3-1 9G2/ 3-2 0G2/ 3-2 4G2/ 3-2 5G2/ 3-2 6G2/ 3-2 7G2/ 3-2 8G2/ 3-2 9G2/ 3-3 1G2/ 3-3 0CARNIVORETRACKSHIPPARIONTRACKSHIPPARIONFOALTRACKS1979 ... TRACKSG 1-1 G 1-2 G 1-3 G 1-9 G 1-8 G 1-7 G 1-6 G 1-1 0G 1-1 1G 1-1 2G 1-1 3G 1-1 4G 1-1 9G 1-2 1G 1-2 2G 1-2 3G2/ 3-1 G2/ 3-2 G2/ 3-3 G2/ 3-6 G2/ 3-5 TUFF BELOWFOOTPRINT LAYERFOOTPRINT TUFF GRABENG2/ 3-7 G2/ 3-8 G2/ 3-9 G2/ 3-1 0NORTHWESTGULLYFAULT ... northern section—G 1-6 , G 1-7 , G 1-8 and G2/ 3-5 —markthe point where the hominids apparently broke stride. Also pres-ent are the tracks of a hipparion.Copyright 1998 Scientific American, Inc.Preserving...

scientific american - 1999 09 - t rex reexamined

... five minutes.Actually,“decapitat-ed snake heads are dangerous for be-tween 20 and 60 minutes after re-moval from the body of the snake,”Such-ard notes. “If that’s not dead, I don’tknow what ... that “educa-tion to prevent snake-bites should includewarnings against han-dling recently killedsnakes.” In the inter-ests of science edu-cation and public safe-ty, SCIENTIFIC AMERICAN therefore ... interrelationships, are in many ways an entirely newspecies to contemplate. But sci-ence has not morphed theminto a benign and tender collec-tion of Cretaceous Care Bears:45 Scientific American September...

scientific american - 2000 01 - we were not alone only we remain why

... groups—deﬁned as long-distancemovers are the subject of this map. The 26 million or soAmericans who move within their counties every year are not included.The majority of long-distance movers are people ... fea-tures, because teeth are often all that re-mains of these tiny creatures after mil-lions of years. Placentals, marsupialsand their closest fossil relatives are char-acterized by so-called ... water.Yet expanding research on treatmentswill not be straightforward: most pa-tients are insured by health-mainte-nance organizations, which are dedicat-ed to reducing costs. Varmus’s scientiﬁcclout...

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