scientific american - 1998 11 - greenland''s mysterious meteor - fire over the ice

scientific american - 1998 11 - greenland's mysterious meteor - fire over the ice

... one of those Tranquilli-ty-base-here -the- Eagle-has-landed,NASA-flight-control jubilation scenes.Laima is the Latvian goddess of goodfortune, and the name was a homageto the heritage of Juris ... ﬁrsttime. The heat is daunting. As the after-noon wears on, the debate betweenJohnson and Fiedel moves ﬁrst oneway, then the other, like a tug-of-war. The debate might never be resolved. The site’s ... rocket. The National Aero-nautics and Space Ad-ministration has consid-ered them for space sci-ence. The Departmentof Defense is interestedin them for use in bal-listic-missile intercep-tors;...

scientific american - 1997 11 - mercury's long, hot afternoon

... laMare of the Austra-lian Antarctic Divisionof the Department of the Environment,Sport and Territorieshas found that be-tween the mid-1950s and the early1970s the sea ice edge in the Antarcticmost ... successive-ly, echoes from the waves map the fea-tures of an oil ﬁeld over time. Oil com-panies then plug the seismic data into the software. Tapping those secret storesthen requires the help ... features of un-known origin that are preferentially oriented north-south,northeast-southwest and northwest-southeast. These linea-ments are called the Mercurian grid. One explanation for the checkered...

scientific american - 1993 11 - reading the genes of extinct species

... in which the disease was inher-ited along with the section of chromo-28 SCIENTIFIC AMERICAN November 1993cause damage or whether blame belongsto the chemicals they carry deep into the lungs.Many ... growth), they do so at the expense of labor in the high-wage coun-tries. They thereby increase income in-equality there. Most citizens are wageearners. In the U.S., 80 percent of the labor force ... andenjoy the beneÞts becomes more fea-sible. The corporation will be able to buy labor in the low-wage markets and sell its products in the remaining high-wage, high-income markets. The largerthe...

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scientific american - 1994 11 - safeguarding computer networks

... MOVE TO THE SAME LOCATION IN THE GELSEROGROUP ANeisseriameningitidisIII-1I-1I-2I-3I-4I-5 I-6 I-7 I-8 I-9 II-1 II-2 II-3 II-4 III-2 III-3 III-4 IV-1 IV-2 IV-3 IV-4 CLONESSUBGROUP ... 54]. The bottom of the bowl rep-resents the energy minimum. The posi-tion of the ball corresponds to the val-ue of the scalar Þeld. Of course, the equations describing the motion of the scalar ... liquiddepends on the energy of the Þeld: the higher the ball in the bowl is, the thick-er the liquid will be. Therefore, if the Þeld initially was very large, the energydropped extremely slowly. The sluggishness...

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

... conclusion. De-spite the hype surround-ing the Þeld, the expertswrote, Òthere is a substan-tial gap between the tech-nology that is availableand the technology that isneeded to realize the po-tential ... loners. The families have very diÝerent char-acters, which reßect the person-ality of the matriarch. In the case of Echo, the family is low-key and nonaggressive.How the 50-year-long rela-tionships ... breast-can-cer test kits,Ó he notes. Because the NIHhelped to fund the project, the govern-ment could establish sublicensing ar-rangements if knowledge about BRCA1were not being used in the...

scientific american - 1995 11 - guardian cells in the brain

... Þnding the genes will helpscientists uncover the biochemistry ofmanic-depression. ÒThere are a lot oftheories about neurotransmitters, butat the end of the day, when they Þnd the genes, theyÕre ... asscripting. These simple programminglanguages can make use of the capabil-ities of the applications in which theyare embedded: a word-processing mac-ro, for example, might use the search-and-replace ... on the X chro-mosome. The paper has been submit-ted to a journal.Elliot S. Gershon of the National In-stitute of Mental Health is now recruit-ing 100 pairs of gay brothers for a ge-netic-marker...

scientific american - 1996 10 - hell's cells

... and Analysis Scientific American October 1996 37Copyright 1996 Scientific American, Inc.European governments are dis-covering the Internet, and theyaren’t too sure they like it. The Net is ... thatthere are more of them available to de-stroy the cancerous cells; these whiteblood cells could then be put back in-side the body to reproduce and to battle the tumor. Further in the future, ... of the 1930s, which pro-duced the infamous dust bowl in parts of the Great Plains. The devastation of the dust bowl led to the creation of the Soil Conservation Service, recently renamed the...

scientific american - 1996 11 - the origins of immunity

... risk factors may affect the expres-sion of the disorder,” the group con-cludes in the Journal of the American Medical Association. The lead author of the study, the larg-est of its kind ever ... psychology at the University of Liverpool,and other academics haverufﬂed a few well-groomedfeathers in the staid linguis-tics community. Their gos-sip-grooming hypothesis as-serts that our ... anotherconcern. The issue is, what does state-of -the- art technology mean?” Garﬁnkelasks. “We’re going to have to establishsome rules rather quickly.”There are some signs that the govern-ment...

scientific american - 1997 01 - parkinson's disease

... de-mand for their services is surg-ing thanks to long-distance price warsand burgeoning Internet use. But manyﬁrms were caught off guard by the runon bandwidth. The trunks of their - ber-optic ... Brynjolfs-son’s model, the more the information-rich accelerate away from the informa-tion-poor (the assumption is that infor-mation-haves will generally prefer tohobnob with other information-haves).This ... bandwidth.Moreover, the telephone people in-sist, several advanced telecommunica-tions technologies, successors to the in-tegrated-services digital network (ISDN),will narrow the gap in the near...

scientific american - 1998 01 - flying over the solar system

... of a tiny needle. They also tested the glucose levels in these volunteers by the finger-stick method. They found thatboth the skin-fluid sample and the fin-ger-stick measured the correct glucoselevels ... outside the cell and the other inside. The component outside the cell is the extracellu-lar matrix; the compressive “girders” inside the cell can be ei-ther microtubules or large bundles of cross-linked ... microprocessors in Japan. The price of the option, called the premium,is the cost the company pays to transferto another party the risk of a precipi-tous fall in the value of the yen. Interestin...

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