scientific american - 1998 12 - animal or vegetable

... 5-androstenediol,1 9-4 -norandrostenedioneand 1 9-5 -norandrostene-diol. (The Merck Indexclassiﬁes 5-androstenedioland 1 9-5 -norandrostenediolas anabolic steroids.)The argument aboutwhether such nonprescrip-tion ... and Human Rights Watch World Report, 1998, Hu-man Rights Watch, New York, 1997. Data from all three organizations are for 1997.RODGER DOYLECopyright 1998 Scientific American, Inc.In 1975 ... drop.SHEHZAD NOORANI Still PicturesCopyright 1998 Scientific American, Inc.News and Analysis34 Scientific American December 1998 Deeper Deep FieldThree years ago the Earth-orbiting Hub-ble Space...

scientific american - 1993 12 - taming africanized killer bees

... quite diÝer-ent kind of neutrino detectorÑthe So-viet -American Gallium Experi-ment, or SAGEÑbegan opera-tion below Mount Andyrchi inthe Russian Caucasus. SAGEincorporates a 60-ton tank ofliquid ... tumor cellmight suÝer 12, or perhaps 15, repeti-tions. Perucho speculated that patientswith such tumors might have a Òmuta-tor mutationÓÑone that introduces er-rors when DNA is replicated or ... normal hu-man liver tissue. The Þrm is preparingto apply for a patent on its bioreactor,which uses a three-dimensional frame-work of nylon screens or biodegradablepolymer meshes to support...

scientific american - 1994 12 - nasa's latest view of the earth

... long-dead NativeAmericans or fossils of even longer-dead hominid ancestors. In a matter ofhours these ancient objects are trans-formed into data Þles that can be storedon a CD-ROM or restored into ... can browse through in-formation from all over the world; Mo-saic Communications Corporation hasannounced a version that can encryptcommercial information such as a cred-it-card number so it ... them cor-respond roughly to neurons and syn-apses in the brain. Like the brain, thenetwork must undergo a ÒtrainingÓ pro-cess. In the police network, input pro-cessors accept personnel informationabout...

scientific american - 1995 12 - the puzzle of consciousness

... behavior. The gene that caus-es Lesch-Nyhan syndrome, which ofteninvolves self-mutilation, is one. Anoth-er is a variant gene for the thyroid hor-mone receptor, which can lead to at-tention-deÞcit ... certify that all in-formation furnished above is true and complete. I un-derstand that anyone who furnishes false or mislead-ing information on this form or who omits material or information requested ... holders owning or holding 1 percent or more of total amount of bonds, mortgages or other securities: none. 12. For completion by non-profit organizations authorized to mail at specialrates. The...

scientific american - 1996 12 - traces of the big bang

... easier-to-use work-stations based on off-the-shelf proces-sors increased in power, fewer buyerswere willing to pay for relatively com-plex supercomputers based on customNews and Analysis40 Scientific ... false or misleading informationon this form or who omits material or information re-quested on the form may be subject to criminal sanc-tions (including fines and imprisonment) and /or civilsanctions ... Beverly Whip-ple of Rutgers University were investi-gating reports of orgasm in women whoSEX AND THE SPINAL CORDA new pathway for orgasmHUMAN BIOLOGYCopyright 1996 Scientific American, Inc.had...

scientific american - 1997 12 - building the biggest

... periodic orbits in a spherical cav-ity are just the trajectories that the par-ticles can take: they shoot back and forthalong a diameter or follow around var-ious polygons with three or more cor-ners. ... normal metabol-ic end points such as carbondioxide and salts. (That wouldmark a distinct change in phy-toremediation efforts: for ex-ample, in heavy-metal extrac-tion plants simply store ... conducting a search on the word“car”), Ultramatch provides keyword-level performance for all the ads.Moreover, SelectCast is unobtrusive,unlike the so-called collaborative ﬁlter-ing schemes in which...

scientific american - 1998 01 - flying over the solar system

... silicon-germanium-carbon technol-ogy developed at France’s Institute ofFundamental Electronics (IEF) for op-toelectronic applications. The Semicon-ductor Research Corporation, a con-sortium ... arti - cially for the sole purpose of storing or- gans for harvesting and transplanta-tion. At about the zenith of surreality, aformer director of the National Institutesof Health reportedly ... “tensegrity”Copyright 1997 Scientific American, Inc.grandfather was a rabbi), he beganwork at the New School for Social Re-search on a more theoretical sort of an-thropology. “I prefer it because it re-quires...

scientific american - 1998 02 - wrapping up the universe

... presents for theworld from the frozen North. —W. Wayt Gibbs in San FranciscoNews and Analysis34 Scientific American February 1998 NATURAL-BORNGUINEA PIGSA start-up discovers genes for tremor and ... ener-gy from the sound wave. Still, the reso-nator has generated enough sonic powerto interest a major appliance manufac-turer, which has a license to incorporatethe resonator as a compressor ... approba-tion, Collins is not entirely with-out critics. John C. Fletcher, for-mer director of the Center forBiomedical Ethics of the Univer-sity of Virginia and an Episco-palian minister before...

scientific american - 1998 03 - inside a virtual human

... CrisisSPECIAL REPORT: THE END OF CHEAP OILCopyright 1998 Scientific American, Inc.Manufacturers of the ma-chine tools that make theparts for a Ford Explorer or a Honda Accord still often ... possible to de-The Bose-Einstein Condensate40 Scientific American March 1998 The Bose-Einstein CondensateThree years ago in a Colorado laboratory, scientists realized a long-standing dream, ... machine errors—devia-tions from speciﬁcation for a part’ssquareness or cylindrical form, for in-stance—can combine to affect the ﬁnalshape of the part. Daniel D. Frey, assis-tant director of...

scientific american - 1998 04 - the unwired world

... either ana-lyze the rocks there more thoroughlythan Viking did or bring samples back.” —W. Wayt Gibbs in San FranciscoCopyright 1998 Scientific American, Inc.Copyright 1998 Scientific American, ... Berke-ley Laboratory used a particle accelera-tor to create them. In 1995 scientists atCERN, the European laboratory forparticle physics near Geneva, synthe-sized atoms of antihydrogen—for ... conduct athorough search for heavy antiparticles.More balloon-borne searches for cos-mic antimatter are on the horizon. Forexample, we are building a new versionof the HEAT detector designed...

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