scientific american - 2004 05 - the time before time

... disrupting the signals between neurons. COPYRIGHT 2004 SCIENTIFIC AMERICAN, INC.28 SCIENTIFIC AMERICAN MAY 2004 In 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 ... WaxmanCOPYRIGHT 2004 SCIENTIFIC AMERICAN, INC.By Gabriele VenezianoTi m e The Beginning of the myth ofCOPYRIGHT 2004 SCIENTIFIC AMERICAN, INC.Or did the universe exist before then? Such a question...

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 - 1997 05 - the 100 - year weather forecast

... from the bubble-enclosed ﬂow-er. The ﬁlters in the kit allow for sepa-rate samples to be taken at differenttimes throughout the day. For example, the peak scent for the orchid purchasedfrom the ... 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 ... 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...

scientific american - 2004 02 - the future looks flexible

... that the mi-grating bats may not be usingtheir echolocation when the collisions occur. Others spec-ulate that the wind turbinesmay be emitting high-pitchedsounds that draw the bats to the ... two other groups the car-charodontosaurs and the spinosaurs—man-aged to evolve similarly supersize propor-tions.) In recent years, a few prime-mover hy-potheses have emerged, attributing the growth ... im-ages of tiny gears, each of which had a diameter ap-proaching that of the proverbial human hair. The black-and-white photographs that graced the pages of na-tional magazines at the time...

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scientific american - 1995 05 - what found the top quark

... than the 1 4- out-of-15 match. To the scientistsÕ de-light, there was a large difference, al-though commercial implications inhibitcandor when they are posed the ques-tion, ÒHow big is the ... 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 ... 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...

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...

scientific american - 2004 04 - has science missed half the brain

... subjects at the time of the serendipitous observation. Of the 30 individuals who received the EP-MRSIscans, 23 reported immediate mood im-provement, the team says in the January issueof the American ... the turn of the 20th century.” The stone “contains morelithium than any other stone on the planet” and “emits a signa-ture one-of-a-kind healing energy.” How does the Golden ‘C’water get these ... blockbuster By GARY STIX1Design the protein2Synthesize peptides3Attach polymers4Join peptide chains5Fold into active protein Gly-Leu-Phe-Asp-Gln Gly-Leu-Phe-Asp-Gln PolymerDESIGNERPROTEIN...

scientific american - 2004 07 - will gene doping change the nature of sport

... PAP6 T cells then attack PAP-containing cancer cell40 SCIENTIFIC AMERICAN JULY 2004 COPYRIGHT 2004 SCIENTIFIC AMERICAN, INC.quires isolating the patient’s white blood cells and thenseparating ... Bayesian theorem: P before × DPafter= P before × D + 100% – P before The probability of God’s existence after the evidence is con-sidered is a function of the probability before times D ... deplete the available hydrogen, then the helium. As the nuclear burning movesoutward to the fresh material in a shell sur-rounding the core, the star bloats into aso-called red giant. When the...

scientific american - 1993 01 - the turbulent birth of the milky way

... CELSIUS)4,9 005, 150 4,650 4,40012-BILLION-YEAR-OLD AGE TRACK15-BILLION-YEAR-OLD AGE TRACKNGC 288NGC 362Copyright 1992 Scientific American, Inc.means that within the halo the only re-maining main-sequence ... declines as the reefs get farther awayfrom two centersÑone in the Indo-Pa-ciÞc and the other in the Caribbean. The outlines of a map marking plum-meting diversity coincide with the con-tours ... ones.Determining the relative ages of the halo and disk reveals much about the sequence of the formation of the gal-axy. On the other hand, it leaves open the question of how old the entire gal-axy actually...

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scientific american - 1993 05 - building soft machines from smart gels

... betatronhave the special advantage of produc-ing their greatest eÝect about 11Ú 2 inch-es below the surface of the body. WithX-ray therapy as used up to the present time, the eÝect is greatest on the ... the sur-face, and decreases with depth. Directuse of the high-speed electrons from the betatron may be even more valu-able than the use of the X-rays. Most of the X-rays continue beyond the pointof ... out that the clinical trials willquickly settle many of the unresolvedquestions about the therapy. Hoth elab-orates that the larger the trials, the soon-er a reliable verdict on the therapy...

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