scientific american - 1994 10 - special issue - life in the universe

... understandingof the laws of nature.The present gaps in our knowl-edge of the laws of nature stand in the way of explaining the ini-tial conditions of the universe, at 10 Ð12second after the nominal ... areversions of string theory that predictsomething like the menu of Þelds in- corporated in the Standard Model.But string theory has had no success-es yet in explaining or predicting any of the numerical ... time, using them to in- fer the primordial distribution of mat-ter. This information can in turn be usedto deduce the initial inhomogeneitiesat 10 Ð12second after the beginning.From the austere...

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

... villainÕs role in other autoimmunediseases: in insulin-dependent diabetes,T lymphocytes destroy insulin-produc-ing cells in the pancreas, and in multiplesclerosis, they direct their fury against the ... near-ly all other genes in the body, those thatcontain the code for the heavy chainsdo not preexist in the fertilized egg. In- stead the code resides in four sets ofmini-genes located in widely ... During these interac-tions, the B cell can also in uence the activity of the T cell.B CELLT CELLLYMPHOKINESCopyright 1993 Scientific American, Inc.uterus and prostate. These findings hintthat...

scientific american - 1997 10 - special issue - the future of transportation

... a con-ference, Regan suggested that two pro-teins being studied in the lab might justlend themselves to the mod-ern-day alchemy required towin the wager. The two proteins, called B-1 and ... Net. The current naming system was de-signed in 1983 as a human-friendly in- terface to the dotted clumps of num-bers that routing computers under-stand. Each organization setting upon-line ... certainuses, that her mother’s life was saved by a pig’s heartvalve. Goodall has alsobeen criticized for saving captured apes,rather than putting money into main-taining habitat in the few...

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

... on the vi-ciousness of their anti-Semitism, eventhough the sites themselves are highlyunlikely to include the center’s rating in their Web home pages.Whatever the source of the ratings,they ... mathemat-ics. He majored in the subject at the Uni-versity of Pune, then applied for a mas-ter’s program in math and computerscience at the Indian Institute of Tech-nology the ﬁrst blind ... Scientific American, Inc.Rendering electronic messagesinto unbreakable code is—de-pending on your point ofview—either the ultimate guarantee ofprivacy from snoopers or the stock -in- trade of Internet-savvy...

scientific american - 1998 10 - how hackers break in

... he calls intervention: establish-ing standards and then measuring per-formance against them. Another highlyeffective technique—having subordi-nates take part in the decision mak-ing—was used ... lying behind the plane of the Milky Way, the gal-axy—named Dwingeloo 1—would beone of the 10 brightest in the sky. Judg-ing from its rate of rotation it has aboutone third the mass of the ... GALAXYDWINGELOO 1 GALAXYCopyright 1998 Scientific American, Inc.Somewhere behind the disk, for ex-ample, are crucial parts of the two big-gest structures in the nearby universe: the Perseus-Pisces...

scientific american - 2002 09 - special issue - a matter of time

... Meanwhile the floorstie the inner frame to the outer one, bracing the entire edifice. In the case of the World Trade Center,which was a state-of -the- art design in the late1960s, the steel-mesh ... MYSTERIOUSFLOWCOPYRIGHT 2002 SCIENTIFIC AMERICAN, INC.events that were once in the unformed future into the con-crete but fleeting reality of the present, and thence relegat-ing them to the fixed past.Obvious ... popular-level books in physics. His scientific research interests include black holes,quantum field theory, the origin of the universe, the nature ofconsciousness and the origin of life. THE AUTHORCONVENTIONAL...

scientific american - 2003 09 - special issue - better brains

... pro-posed second-generation system known asComputer-Assisted Passenger Pre-Screening,or CAPPS II. In termsof the variety of in- formation, the sys-tem goes much fur-ther than the 1.0 ver-sion—and ... another molecule that tricks the cellsinto taking it up and transferring it into brain tissueor by genetically engineering cells to make FGF andthen transplanting those cells into the brain. ... age beginning in the 1970s, they were in surplus and so had low wages relative totheir fathers and hence low fertility. The slightincrease in fertility since the late 1990s couldbe the effect...

scientific american - 1993 10 - is los angeles winning the war on smog

... belongedtogether. For example, if three amino ac-idsÑcall them A, B and CÑare linkedtogether in some order in a chain, the sequence could be determined in the following way. After labeling the chains,they ... the air mass in- land, the inversion layer traps air pol-lutants in the cool air near the groundwhere people live and breathe. The mountains that surround the regioncompound the problem; they ... insulin was nota single chain but rather four cross-linked chains. When he presented the results to his mentor, Tiselius suggest-ed that they rush to publish a paper to-gether. ÒI was rather...

scientific american - 1994 03 - visiting yourself in the past

... of the original miner-als in the peridotite. Some minerals,such as clinopyroxene, melt more easi-ly than do others and hence rapidly de-crease in abundance during the melt-ing. Moreover, the ... FULLERCopyright 1994 Scientific American, Inc.Mayewski hopes better insight into the inconstant nature of the sun willenable researchers to determine whether the present, human-generated increas-es in ... during the 1980s. Butthis decline reßects improved nutrition-al conditions in Asia alone. During the same period, the number of people hav-ing energy-deÞcient diets in Latin Amer-ica, the...

scientific american - 1994 01 - searching for strange quark matter

... of the nuclei then spin in opposi-tion to the external Þeld in high-energyorientations. The process is adiabatic,meaning the entropy remains un-changed. The resulting spin distributionis the ... liverfailure.Four neurotoxins have been studied in detail. Of these, anatoxin-a and ana-toxin-a(s) seem unique to cyanobacte-ria. The other twoÑsaxitoxin and neo-saxitoxinÑarise in certain marine algaeas ... Mark-stein, a Berlin actress who claimed in 1935 to be EinsteinÕs long-lost daugh-ter. The archives contain plain evidencethat Einstein sired a daughter by Milevabefore their wedding, whom the...

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