Congress Boosts NSF, NASA Budgets     

Anderson C  Mervis J 《Science (New York, N.Y.)》1993,262(5131):173

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ORI Faces High Hurdle in Gallo Case     

Anderson C 《Science (New York, N.Y.)》1993,262(5136):982

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Identification of a cellular cofactor required for infection by feline leukemia virus     

Anderson MM  Lauring AS  Burns CC  Overbaugh J 《Science (New York, N.Y.)》2000,287(5459):1828-1830

Retroviral infection involves continued genetic variation, leading to phenotypic and immunological selection for more fit virus variants in the host. For retroviruses that cause immunodeficiency, pathogenesis is linked to the emergence of T cell-tropic, cytopathic viruses. Here we show that an immunodeficiency-inducing, T cell-tropic feline leukemia virus (FeLV) has evolved such that it cannot infect cells unless both a classic multiple membrane-spanning receptor molecule (Pit1) and a second coreceptor or entry factor are present. This second receptor component, which we call FeLIX, was identified as an endogenously expressed protein that is similar to a portion of the FeLV envelope protein. This cellular protein can function either as a transmembrane protein or as a soluble component to facilitate infection.  相似文献   

THE EFFECT OF COLORED IONS ON THE PHOTO-INACTIVATION OF INVERTASE     

Lardy H  Anderson TF 《Science (New York, N.Y.)》1942,95(2465):330-331

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Physics. Colliding clouds may hone physical constants     

Anderson M 《Science (New York, N.Y.)》2007,316(5823):354

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NIH to Appeal Patent Decision     

Anderson C 《Science (New York, N.Y.)》1993,259(5093):302

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Charge transfer equilibria between diamond and an aqueous oxygen electrochemical redox couple     

Chakrapani V  Angus JC  Anderson AB  Wolter SD  Stoner BR  Sumanasekera GU 《Science (New York, N.Y.)》2007,318(5855):1424-1430

Undoped, high-quality diamond is, under almost all circumstances, one of the best insulators known. However, diamond covered with chemically bound hydrogen shows a pronounced conductivity when exposed to air. This conductivity arises from positive-charge carriers (holes) and is confined to a narrow near-surface region. Although several explanations have been proposed, none has received wide acceptance, and the mechanism remains controversial. Here, we report the interactions of hydrogen-terminated, macroscopic diamonds and diamond powders with aqueous solutions of controlled pH and oxygen concentration. We show that electrons transfer between the diamond and an electrochemical reduction/oxidation couple involving oxygen. This charge transfer is responsible for the surface conductivity and also influences contact angles and zeta potentials. The effect is not confined to diamond and may play a previously unrecognized role in other disparate systems.  相似文献   

Geothermal convection through oceanic crust and sediments in the Indian ocean     

Anderson RN  Hobart MA  Langseth MG 《Science (New York, N.Y.)》1979,204(4395):828-832

Closely spaced heat flow surveys at four sites on the flanks of the Central Indian Ridge and the Southeast Indian Ridge delineate a pattern of oscillatory heat flow which can only result from cellular convection of oceanic bottom water through the oceanic crust and overlying sediment. These cells have a wavelength of 5 to 10 kilometers and are presently active in sea floor 18 x 10(6), 25 x 10(6), and 45 x 10(6) years old of the Crozet Basin and in sea floor 55 x 10(6) years old of the Madagascar Basin. The precise measurement of nonlinear temperature profiles makes it possible to calculate the conductive and convective heat transfer components through the sea floor. Even in the oldest sites, geothermal convection is still a major component of heat transfer through both the crust and sedimentary layers. These observations coupled with the results of earlier oceanwide geothermal studies indicate that more than one-third of the entire surface area of the world's ocean floor contains presently active geothermal convection that is cellular in plan form.  相似文献   

Abscisic Acid Induces Formation of Floating Leaves in the Heterophyllous Aquatic Angiosperm Potamogeton nodosus     

Anderson LW 《Science (New York, N.Y.)》1978,201(4361):1135-1138

Potamogeton nodosus tubers produce floating-type instead of submersed-type leaves when exposed to 10(-5) molar synthetic abscisic acid. Abscisic acid-induced leaves have stomata on upper leaf surfaces and higher width/length ratios than controls. These effects are wholly or partially overcome by simultaneous exposure to abscisic acid combined with gibberellic acid, kinetin, or benzyladenine.  相似文献   

The Earth as a planet: paradigms and paradoxes     

Anderson DL 《Science (New York, N.Y.)》1984,223(4634):347-355

The independent growth of the various branches of the earth sciences in the past two decades has led to a divergence of geophysical, geochemical, geological, and planetological models for the composition and evolution of a terrestrial planet. Evidence for differentiation and volcanism on small planets and a magma ocean on the moon contrasts with hypotheses for a mostly primitive, still undifferentiated, and homogeneous terrestrial mantle. In comparison with the moon, the earth has an extraordinarily thin crust. The geoid, which should reflect convection in the mantle, is apparently unrelated to the current distribution of continents and oceanic ridges. If the earth is deformable, the whole mantle should wander relative to the axis of rotation, but the implications of this are seldom discussed. The proposal of a mantle rich in olivine violates expectations based on evidence from extraterrestrial sources. These and other paradoxes force a reexamination of some long-held assumptions.  相似文献