scientific american special edition - 2003 vol 13 no3 - new light on the solar system

... shaped the landscape over the past several billion years. contents 2003 2003 New Light on the Solar System SCIENTIFIC AMERICAN Volume 13 Number 3 C2 SCIENTIFIC AMERICAN 28 4 COPYRIGHT 2003 SCIENTIFIC ... heat and light our solar system. 8 SCIENTIFIC AMERICAN NEW LIGHT ON THE SOLAR SYSTEM DON DIXON Corona Convective zone Photosphere Core Ra...

Ngày tải lên: 12/05/2014, 16:27

... Ardipithecus skeleton in the Middle Awash region. As White and his team extract these exciting new fos- sils from the enclosing stone, reconstruct them and prepare them for study, the pa- leoanthropological ... seven- million-year-old skull. www.sciam.com NEW LOOK AT HUMAN EVOLUTION 1 New Look at Human Evolution is published by the staff of Scientific American, with project ma...

Ngày tải lên: 12/05/2014, 16:27

... be- cause the dual theory would yield the same final results. Unfortunately, the idea presented a chicken-and-egg problem. Once proved, the Montonen-Olive conjecture could leap beyond conventional ... absorbing them into a redefinition, or “renormal- ization,” of only a few physical constants, such as the charge and mass of the elec- tron. (The minimum version of the Stan- dard M...

Ngày tải lên: 12/05/2014, 16:26

... on Bikini and Enewetak. The top- soil on the atolls has high levels of ra- dioactive cesium 137 , strontium 90, plu- tonium 239, plutonium 240 and americi- um 241. Of these fallout elements, only 26 ... enclosed on the northern side, a configuration that gives rise to drastic seasonal changes in the winds and currents. These monsoons, a variation on the Arabic word mausim, m...

Ngày tải lên: 12/05/2014, 16:24

... used in conjunction with a drug that turns the promoter region on and off. So long as the patient takes the drug, the pro- moter region of the engineered gene that has ensconced itself into the nucleus ... intestines. YOUR NEW BODY Copyright 1999 Scientific American, Inc. YOUR NEW BODY YOUR NEW BODY swer these questions: What specific concentrations of the mole- cules...

Ngày tải lên: 12/05/2014, 16:25

... loss from the body of the hor- mone, which would otherwise be metabolized in hours. In the body, neither the testoste- rone nor the ester arouses sus- picion, because both are found there naturally. Sports ... Arbitration for Sport. The court must then decide within 24 hours whether to uphold or over- turn the sanction. The court, set up in the mid-1980s, comprises rep- rese...

Ngày tải lên: 12/05/2014, 16:26

... including the pres- ence or absence of nearby radiation-emitting stars. On the other hand, astronomer David F. Gray of the Univer- sity of Western Ontario in Canada has challenged the existence of the ... unusual greenish-gray rock. Back at the National Aeronautics and Space Ad- ministration Johnson Space Center and at Stanford University, researchers con- firmed that the 1.9-...

Ngày tải lên: 12/05/2014, 16:23

... some of the only in- formation on the attitudes and sexual be- havior of 1 5- to 19-year-olds. The survey The female condom’s manufac- turer, the Female Health Com- pany, reports that the plastic vaginal ... information on HPV and other STDs. ASHA also sponsors the National STD Hotline (80 0-2 2 7-8 922) and offers pamphlets and educational ma- terials on STD-relate...

Ngày tải lên: 12/05/2014, 16:23

... Warring- ton of the Dementia Research Group at National Hospital in London and others have confirmed the phenomenon.) Much of the evidence for the per- sonal intelligences has come from research in the ... decade on emotion- al intelligence and on the development in children of a “theory of mind” the realization that human beings have in- tentions and act on the basis of t...

Ngày tải lên: 12/05/2014, 16:24

... mission to Mars or the construction of a base on the moon. But these justifications for the sta- tion are largely myths. Here are the facts, plain as potatoes: The International Space Station is ... fax +44 140 48 4-1 320 JAPAN NIKKEI INTERNATIONAL LTD . +81 3-5 25 9-2 690 fax +81 3-5 25 9-2 679 KOREA BISCOM , INC. +822 73 9-7 840 fax +822 73 2-3 662 HONG KONG HUTTON...

Ngày tải lên: 12/05/2014, 16:24