POLYGONBODEN ON MT. DESERT ISLAND,MAINE     

Nichols RL  Nichols F 《Science (New York, N.Y.)》1936,83(2146):161-162

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Unexamined bodies of evidence     

Schoeninger MJ  Bada JL  Masters PM  Bettinger RL  White TD 《Science (New York, N.Y.)》2011,332(6032):916

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For the record     

Mayo SL  Baldwin RL 《Science (New York, N.Y.)》1994,263(5146):455

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Multiple Genotypes in Individuals of Claytonia virginica     

Lewis WH  Oliver RL  Luikart TJ 《Science (New York, N.Y.)》1971,172(3983):564-565

Supernumerary chromosomes are common among plants of Claytonia virginica found in a weedy population near the southwestern edge of its distribution. Roots, stems, and microsporocytes vary in chromosome number within the same plant in 68 percent of the population studied.  相似文献   

Late Pliocene Homo and hominid land use from Western Olduvai Gorge,Tanzania     

Blumenschine RJ  Peters CR  Masao FT  Clarke RJ  Deino AL  Hay RL  Swisher CC  Stanistreet IG  Ashley GM  McHenry LJ  Sikes NE  Van Der Merwe NJ  Tactikos JC  Cushing AE  Deocampo DM  Njau JK  Ebert JI 《Science (New York, N.Y.)》2003,299(5610):1217-1221

Excavation in the previously little-explored western portion of Olduvai Gorge indicates that hominid land use of the eastern paleobasin extended at least episodically to the west. Finds included a dentally complete Homo maxilla (OH 65) with lower face, Oldowan stone artifacts, and butchery-marked bones dated to be between 1.84 and 1.79 million years old. The hominid shows strong affinities to the KNM ER 1470 cranium from Kenya (Homo rudolfensis), a morphotype previously unrecognized at Olduvai. ER 1470 and OH 65 can be accommodated in the H. habilis holotype, casting doubt on H. rudolfensis as a biologically valid taxon.  相似文献   

Stilbestrol     

Preston RL 《Science (New York, N.Y.)》1960,132(3440):1680

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Elastomeric transistor stamps: reversible probing of charge transport in organic crystals     

Sundar VC  Zaumseil J  Podzorov V  Menard E  Willett RL  Someya T  Gershenson ME  Rogers JA 《Science (New York, N.Y.)》2004,303(5664):1644-1646

We introduce a method to fabricate high-performance field-effect transistors on the surface of freestanding organic single crystals. The transistors are constructed by laminating a monolithic elastomeric transistor stamp against the surface of a crystal. This method, which eliminates exposure of the fragile organic surface to the hazards of conventional processing, enables fabrication of rubrene transistors with charge carrier mobilities as high as approximately 15 cm2/V.s and subthreshold slopes as low as 2nF.V/decade.cm2. Multiple relamination of the transistor stamp against the same crystal does not affect the transistor characteristics; we exploit this reversibility to reveal anisotropic charge transport at the basal plane of rubrene.  相似文献   

Atomic memory for correlated photon states     

van der Wal CH  Eisaman MD  André A  Walsworth RL  Phillips DF  Zibrov AS  Lukin MD 《Science (New York, N.Y.)》2003,301(5630):196-200

We experimentally demonstrate emission of two quantum-mechanically correlated light pulses with a time delay that is coherently controlled via temporal storage of photonic states in an ensemble of rubidium atoms. The experiment is based on Raman scattering, which produces correlated pairs of spin-flipped atoms and photons, followed by coherent conversion of the atomic states into a different photon beam after a controllable delay. This resonant nonlinear optical process is a promising technique for potential applications in quantum communication.  相似文献   

Reversal of bone loss in mice by nongenotropic signaling of sex steroids     

Kousteni S  Chen JR  Bellido T  Han L  Ali AA  O'Brien CA  Plotkin L  Fu Q  Mancino AT  Wen Y  Vertino AM  Powers CC  Stewart SA  Ebert R  Parfitt AM  Weinstein RS  Jilka RL  Manolagas SC 《Science (New York, N.Y.)》2002,298(5594):843-846

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X-ray Damage to CF3CO2-Terminated Organic Monolayers on Si/Au: Principal Effect of Electrons     

Laibinis PE  Graham RL  Biebuyck HA  Whitesides GM 《Science (New York, N.Y.)》1991,254(5034):981-983

The relative importance of x-rays alone and of x-ray-generated primary and secondary electrons in damaging organic materials was explored by use of self-assembled monolayers (SAMs) on multilayer thin-film supports. The substrates were prepared by the deposit of thin films of silicon (0, 50, 100, and 200 angstroms) on thick layers of gold (2000 angstroms). These systems were supported on chromium-primed silicon wafers. Trifluoroacetoxy-terminated SAMs were assembled on these substrates, and the samples were irradiated with common fluxes of monochromatic aluminum K(alpha) x-rays. The fluxes and energy distributions of the electrons generated by interactions of the x-rays with the various substrates, however, differed. The substrates that emitted a lower flux of electrons exhibited a slower loss of fluorine from the SAMs. This observation indicated that the electrons-and not the x-rays themselves-were largely responsible for the damage to the organic monolayer.  相似文献