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991.
C. R. Purcell R. Balasubramanyam M. G. Burton A. J. Walsh V. Minier M. R. Hunt-Cunningham L. L. Kedziora-Chudczer S. N. Longmore T. Hill I. Bains P. J. Barnes A. L. Busfield P. Calisse N. H. M. Crighton S. J. Curran T. M. Davis J. T. Dempsey G. Derragopian B. Fulton M. G. Hidas M. G. Hoare J.-K. Lee E. F. Ladd S. L. Lumsden T. J. T. Moore M. T. Murphy R. D. Oudmaijer M. B. Pracy J. Rathborne S. Robertson A. S. B. Schultz J. Shobbrook P. A. Sparks J. Storey T. Travouillion 《Monthly notices of the Royal Astronomical Society》2006,367(2):553-576
992.
J. Lee 《Environmental Geology》1986,9(1):23-30
Ireland's soil regions consist largely of Luvisols, Cambisols, and Gleysols. Approximately 60% of Ireland's land area is subject
to varying degrees of soil limitations. Twenty-five percent of the land area comprises wet lowland mineral soils.
Ninety percent of Ireland's agricultural area comprises pasture, hay, and silage. Approximately 30% of the agricultural area
is devoted to dairying, and 55% to cattle production. is devoted to dairying, and 55% to cattle production.
Trends in agricultural land use indicate that tillage declined substantially while livestock showed a substantial increase
particularly in the decade 1965–1975. Research concludes that over 2.8 million ha has a capacity to carry at least 100 LU/40
ha (100 acres).
Levels of fertilizer use in Ireland are below EEC levels. The highest fertilizer use levels are associated with the eastern
and southern areas of Ireland. Tillage crops occupy only 10% of the agricultural area, while they account for 26% of tertilizer
and lime use. 相似文献
993.
Wodzimierz Kluniak William H. Lee 《Monthly notices of the Royal Astronomical Society》2002,335(1):L29-L32
In three-dimensional smooth particle hydrodynamic simulations of the coalescence of a quark star with a pseudo-Newtonian black hole all of the quark matter is quickly accreted by the black hole. The Madsen–Caldwell–Friedman argument against the existence of quark stars may need to be re-examined. 相似文献
994.
995.
An accessible model for interstellar OH/H2O maser associations is presented. It can be classified into radiative pumping model. It can close the dynamical cycle of H2O and OH species, and can give an interpretation on interstellar OH/H2O associations. A reasonable scheme for both regeneration and destruction of interstellar H2O and OH molecules is argued. Our model has overcome the defects of former radiative models, and is compatible with astronomical conditions. It is shown that the rotational population of H2O and OH in these regions is much less affected by collisions than by radiation. Some experiments have confirmed our proposal. 相似文献
996.
997.
998.
999.
Charles S. Cockell Pascal Lee Gordon Osinski Gerda Horneck Paul Broady 《Meteoritics & planetary science》2002,37(10):1287-1298
Abstract— Asteroid and comet impacts on Earth are commonly viewed as agents of ecosystem destruction, be it on local or global scales. However, for some microbial communities, impacts may represent an opportunity for habitat formation as some substrates are rendered more suitable for colonization when processed by impacts. We describe how heavily shocked gneissic crystalline basement rocks exposed at the Haughton impact structure, Devon Island, Nunavut, Arctic Canada, are hosts to endolithic photosynthetic microorganisms in significantly greater abundance than lesser‐shocked or unshocked gneisses. Two factors contribute to this enhancement: (a) increased porosity due to impact fracturing and differential mineral vaporization, and (b) increased translucence due to the selective vaporization of opaque mineral phases. Using biological ultraviolet radiation dosimetry, and by measuring the concentrations of photoprotective compounds, we demonstrate that a covering of 0.8 mm of shocked gneiss can provide substantial protection from ultraviolet radiation, reducing the inactivation of Bacillus subtilis spores by 2 orders of magnitude. The colonisation of the shocked habitat represents a potential mechanism for pioneer microorganisms to invade an impact structure in the earliest stages of post‐impact primary succession. The communities are analogous to the endolithic communities associated with sedimentary rocks in Antarctica, but because they occur in shocked crystalline rocks, they illustrate a mechanism for the creation of microbial habitats on planetary surfaces that do not have exposed sedimentary units. This might have been the case on early Earth. The data have implications for the microhabitats in which biological signatures might be sought on Mars. 相似文献
1000.
L. Cayón A. J. Banday T. Jaffe H. K. Eriksen F. K. Hansen K. M. Gorski J. Jin 《Monthly notices of the Royal Astronomical Society》2006,369(2):598-602
Higher Criticism (HC) has been proposed by Donoho & Jin as an effective statistic to detect deviations from Gaussianity. Motivated by the success of the Bianchi VIIh model in addressing many of the anomalies observed in the Wilkinson Microwave Anisotropy Probe ( WMAP ) data (Jaffe et al.), we present calculations in real and in wavelet space of the HC statistic of the Bianchi-corrected WMAP first-year data. At the wavelet scale of 5°, the HC of the WMAP map drops from a value above the 99 per cent confidence level (c.l.) to a value below the 68 per cent CL when corrected by the Bianchi template. An important property of the HC statistic is its ability to locate the pixels that account for the deviation from Gaussianity. The analysis of the uncorrected WMAP data pointed to a cold spot in the Southern hemisphere, centred at l ∼ 209°, b ∼−57° . The HC of the Bianchi-corrected map indicates that this spot remains prominent, albeit at a level completely consistent with Gaussian statistics. Consequently, it is debatable how much emphasis should be placed on this residual feature, but we consider the effect of modestly increasing the scaling of the template. A factor of only 1.2 renders the spot indistinguishable from the background level, with no noticeable impact on the results published in Jaffe et al. for the low- l anomalies, large-scale power asymmetry or wavelet kurtosis. A trivial interpretation would be that the Bianchi template may require a small enhancement of power on scales corresponding to the wavelet scale of 5°. 相似文献