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This article describes research aimed at improving modeling of student age-groups in the ONS subnational population projections for England. A number of data-sources were investigated, and the research focused on Higher Education Statistics Agency data. Although the coverage of HESA data is not sufficient to enable student populations to be projected separately, the data have been used to devise an adjustment method for the student-age population. Both the data and method will be monitored and, if appropriate, used in future projections.  相似文献   
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This article outlines the main features of the population of England and Wales in 1999. Where 1999 figures have not yet been produced, data for the latest available year are given.  相似文献   
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This article describes the most recent process of projecting population at the subnational level in England. It briefly explains the reasons why projecting population at the subnational level is important, describes the model and how it was used to produce the latest set of long-term subnational population projections in England published by the Office for National Statistics (ONS) in 1998. The article then discusses how the model may be applied to answer various 'what-if' questions about future population.  相似文献   
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di Primio R  Horsfield B  Guzman-Vega MA 《Nature》2000,406(6792):173-176
Knowledge of the timing and location of petroleum formation is important in assessing the extent of available reserves in hydrocarbon-forming basins. This can be predicted from the thermal history of a basin and the kinetic parameters that characterize the thermal breakdown of kerogen in source rocks. At present, the kinetic parameters of kerogen breakdown are experimentally determined using immature rock samples from basin margins, but questions remain about the accuracy of this approach, especially when significant variability is observed within individual source units. Here we show that the kinetics of hydrocarbon generation from petroleum asphaltenes can be used to determine the temperature conditions of the actual source rock at the time of expulsion of the sampled petroleum. This relationship reflects the structural similarity of asphaltenes to the parent kerogen. We expect that our approach may be used as a comparatively simple alternative method for assessing the petroleum generation characteristics of a given basin, which will allow for better estimates of the available oil resources and the risks associated with their exploration.  相似文献   
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Zusammenfassung Im Verlauf elektronenmikroskopischer Untersuchungen der Thrombocyten des Menschen wurden Fibrillen von etwa 200 å im Durchmesser beobachtet, die Bündel bilden, welche sich durch die ganze Zelle und in die cytoplasmatischen Fortsätze erstrecken können. Diese Struktur steht mit dem Vorhandensein eines kontraktilen Proteins im Zusammenhang.  相似文献   
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Migration figures are notoriously problematic to compile, and this is primarily due to complexities in establishing the size and composition of those leaving the UK to live overseas. This article summarises an Office for National Statistics (ONS) investigation into the potential use of data held by countries receiving UK citizens in order to improve the accuracy of emigration figures.  相似文献   
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