Molecular medicine. The cholesterol quartet     

Goldstein JL  Brown MS 《Science (New York, N.Y.)》2001,292(5520):1310-1312

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Composition and dynamics of plasma in Saturn's magnetosphere     

Young DT  Berthelier JJ  Blanc M  Burch JL  Bolton S  Coates AJ  Crary FJ  Goldstein R  Grande M  Hill TW  Johnson RE  Baragiola RA  Kelha V  McComas DJ  Mursula K  Sittler EC  Svenes KR  Szegö K  Tanskanen P  Thomsen MF  Bakshi S  Barraclough BL  Bebesi Z  Delapp D  Dunlop MW  Gosling JT  Furman JD  Gilbert LK  Glenn D  Holmlund C  Illiano JM  Lewis GR  Linder DR  Maurice S  McAndrews HJ  Narheim BT  Pallier E  Reisenfeld D  Rymer AM  Smith HT  Tokar RL  Vilppola J  Zinsmeyer C 《Science (New York, N.Y.)》2005,307(5713):1262-1266

During Cassini's initial orbit, we observed a dynamic magnetosphere composed primarily of a complex mixture of water-derived atomic and molecular ions. We have identified four distinct regions characterized by differences in both bulk plasma properties and ion composition. Protons are the dominant species outside about 9 RS (where RS is the radial distance from the center of Saturn), whereas inside, the plasma consists primarily of a corotating comet-like mix of water-derived ions with approximately 3% N+. Over the A and B rings, we found an ionosphere in which O2+ and O+ are dominant, which suggests the possible existence of a layer of O2 gas similar to the atmospheres of Europa and Ganymede.  相似文献   

Ethics. The ISSCR guidelines for human embryonic stem cell research     

Daley GQ  Ahrlund Richter L  Auerbach JM  Benvenisty N  Charo RA  Chen G  Deng HK  Goldstein LS  Hudson KL  Hyun I  Junn SC  Love J  Lee EH  McLaren A  Mummery CL  Nakatsuji N  Racowsky C  Rooke H  Rossant J  Schöler HR  Solbakk JH  Taylor P  Trounson AO  Weissman IL  Wilmut I  Yu J  Zoloth L 《Science (New York, N.Y.)》2007,315(5812):603-604

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Potential for Converting Wood into Plastics: Chemicals from wood may regain importance as the cost of petroleum continues to rise     

Goldstein IS 《Science (New York, N.Y.)》1975,189(4206):847-852

The conversion of wood into chemicals for the production of most of our synthetic plastics, fibers, and rubbers is technically feasible. With refinements in technology a large integrated plant utilizing all components of the wood for production of ethanol (to be further processed to ethylene and butadiene), phenols and furfural would be approaching economic feasibility as well at current petrochemical prices. If crude oil prices continue to climb at a faster rate than wood costs, the economic feasibility of chemicals for polymers from wood would become certain. Although technical feasibility has not been established, synthetic oils from liquefaction of wood might serve as feedstocks for cracking to chemicals in the same way that crude oil is presently used. The fulfillment of all our polymer needs from wood as a raw material should not place an impossible burden on our wood supply, but might actually improve the availability of wood for lumber, plywood and pulp by providing a use for less valuable wood which would allow reforestation and improved forest management.  相似文献   

Mechanisms of magma generation beneath hawaii and mid-ocean ridges: uranium/thorium and samarium/neodymium isotopic evidence     

Sims KW  Depaolo DJ  Murrell MT  Baldridge WS  Goldstein SJ  Clague DA 《Science (New York, N.Y.)》1995,267(5197):508-512

Measurements of uranium/thorium and samarium/neodymium isotopes and concentrations in a suite of Hawaiian basalts show that uranium/thorium fractionation varies systematically with samarium/neodymium fractionation and major-element composition; these correlations can be understood in terms of simple batch melting models with a garnet-bearing peridotite magma source and melt fractions of 0.25 to 6.5 percent. Midocean ridge basalts shows a systematic but much different relation between uranium/thorium fractionation and samarium/neodymium fractionation, which, although broadly consistent with melting of a garnet-bearing peridotite source, requires a more complex melting model.  相似文献   

Partially Molten Middle Crust Beneath Southern Tibet: Synthesis of Project INDEPTH Results   总被引：23，自引：0，他引：23  

KD Nelson  W Zhao  LD Brown  J Kuo  J Che  X Liu  SL Klemperer  Y Makovsky  R Meissner  J Mechie  R Kind  F Wenzel  J Ni  J Nabelek  C Leshou  H Tan  W Wei  AG Jones  J Booker  M Unsworth  WSF Kidd  M Hauck  D Alsdorf  A Ross  M Cogan  C Wu  E Sandvol  M Edwards 《Science (New York, N.Y.)》1996,274(5293):1684-1688

INDEPTH geophysical and geological observations imply that a partially molten midcrustal layer exists beneath southern Tibet. This partially molten layer has been produced by crustal thickening and behaves as a fluid on the time scale of Himalayan deformation. It is confined on the south by the structurally imbricated Indian crust underlying the Tethyan and High Himalaya and is underlain, apparently, by a stiff Indian mantle lid. The results suggest that during Neogene time the underthrusting Indian crust has acted as a plunger, displacing the molten middle crust to the north while at the same time contributing to this layer by melting and ductile flow. Viewed broadly, the Neogene evolution of the Himalaya is essentially a record of the southward extrusion of the partially molten middle crust underlying southern Tibet.  相似文献   

Ulysses solar wind plasma observations at high southerly latitudes   总被引：1，自引：0，他引：1  

Phillips JL  Bame SJ  Feldman WC  Gosling JT  Hammond CM  McComas DJ  Goldstein BE  Neugebauer M  Scime EE  Suess ST 《Science (New York, N.Y.)》1995,268(5213):1030-1033

Solar wind plasma observations made by the Ulysses spacecraft through -80.2 degrees solar latitude and continuing equatorward to -40.1 degrees are summarized. Recurrent high-speed streams and corotating interaction regions dominated at middle latitudes. The speed of the solar wind was typically 700 to 800 kilometers per second poleward of -35 degrees . Corotating reverse shocks persisted farther south than did forward shocks because of the tilt of the heliomagnetic streamer belt. Sporadic coronal mass ejections were seen as far south as -60.5 degrees . Proton temperature was higher and the electron strahl was broader at higher latitudes. The high-latitude wind contained compressional, pressure-balanced, and Alfvénic structures.  相似文献   

Hayflick-NIH Settlement     

Strehler BL  Abraham S  Bayreuther K  Bienenstock A  Binstock R  Birren J  Blumenthal HT  Brautbar C  Brody EM  Brody H  Comfort A  Cottle RW  Danielli JF  Danon D  Datan N  Ebbesen P  Elsen A  Freundt EA  Gallop PM  Girardi AJ  Glenn PF  Goheen JD  Goldstein S  Good RA  Goodlin RC  Granoff A  Gray A  Haber PA  Hamparian VV  Hijmans W  Holliday R  Horvath SM  Houck JC  Huebner RJ  Itoh H  Jukes T  Kaplan HS  Kirkman H  Kuwert E  Leiderman PH  Liss A  Litwin J  Lubin B  Macieira-Coelho A  Madoff S  Maletta GJ  Maramorosch K  Martin GM 《Science (New York, N.Y.)》1982,215(4530):240-242

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Quasars: Millisecond-of-Arc Structure Revealed by Very-Long-Baseline Interferometry     

Knight CA  Robertson DS  Rogers AE  Shapiro II  Whitney AR  Clark TA  Goldstein RM  Marandino GE  Vandenberg NR 《Science (New York, N.Y.)》1971,172(3978):52-54

Observations with the Goldstone-Haystack radio interferometer of the quasars 3C 279 and 3C 273 have disclosed the presence of fine structure in their radio emissions. Although the interpretation is not unique, the fringe-amplitude data for quasar 3C 279 are quite consistent with emissions from two points, each contributing equally to the correlated flux. The separation of the two points is estimated to be (1.55 +/- 0.05) x 10(-3) arc second, or about 20 light years at the distance of 3 x 10(9) light years inferred from optical red-shift data. The formal uncertainty in the right-ascension component of the separation is about 6 x 10(-6) arc second; differential proper motion in this direction at half the speed of light could be discerned within a year. The fringe-amplitude data of quasar 3C 273 allow similar, but less definitive, interpretations.  相似文献   

Hazard,risk and agrarian adaptations in a hyperarid watershed: El Niño floods,streambank erosion,and the cultural bounds of vulnerability in the Andean Middle Horizon     

Paul S. Goldstein  Francis J. Magilligan 《CATENA》2011

Peru's Osmore drainage, also known as the Moquegua Valley, is one of the driest regions on Earth, yet agricultural development has supported complex societies in the basin for almost 4000 yrs because of canal construction and irrigation. We compare the distinct agrarian and settlement systems of three coeval archaeological cultures in this arid region, Huaracane, Wari and Tiwanaku, and how each adapted—or failed to adapt—to geomorphic and climatic hazards. Systematic settlement pattern survey and radiocarbon dating along with geomorphological analysis of flood history and riverine processes permit detailed discussion of agrarian strategies during the Formative (1800 BC–AD 500) and Middle Horizon (AD 500–1000) periods, with distinct settlement “niches” in terms of agricultural practices and longitudinal position in the drainage, and lateral location relative to the floodplain. These adaptive strategies each manifest distinct “bounds of adaptability” to natural hazard, climate events and social stressors, and thus varying risk profiles. Besides the continual risk associated with sustained droughts, the Atacama and Peruvian Coastal Desert and culturally connected highland Altiplano are also vulnerable to the vagaries of the El Niño-Southern Oscillation (ENSO) leading to catastrophic floods in the mid-valley during warm phase ENSOs, in tandem with simultaneous hazards in other regions inhabited by these transregional cultures. By comparing the archaeological record of Wari, Huaracane, and Tiwanaku culture settlements with geomorphic signatures of catastrophic El Niños, we show that the viability of each cultural sequence depended on specific relationships to floodplain streambank erosion, construction and reworking over multiple time scales.  相似文献