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The statistical survey of 1 385 french titles, starting with annales, journal or revue, helps to understand the development of “scientific” journals in France from the beginning of the 19th century until today. This 200 years history provides perspectives about the growth and decline of publishing. It includes scientific titles within the publishing production and underscores the importance of stimulation of the flow of ideas and information, through frequency and growth analysis.  相似文献   
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The timing of the introduction, proliferation and decline of backed artefacts in Australia has been much debated. In south-eastern Australia, after initially appearing at least 8500 years ago, backed artefacts greatly increased in number between 4000 and 3500 years ago to the extent that they are found in numerous sites and are recorded in large numbers in individual sites from that time. From about 1500 years ago they declined markedly in number and had seemingly disappeared by the time of British colonization. Models explaining their proliferation advance the proposition that increased backed artefact production was triggered by heightened foraging risk and/or social re-organisation brought about by a change in climate to a regime which was cooler and drier than any other time during the Holocene combined with intensified ENSO climatic conditions. Our study develops this hypothesis by inferring the use of backed artefacts at Mussel Shelter in the Sydney Basin through an integrated use-wear and residue analysis. These inferences provide new insights into the nature of the evolutionary changes in tool production and use in response to the period of altered climatic conditions.  相似文献   
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ABSTRACT This paper analyses the evolution of city size distribution in the United States throughout the twentieth century. It tests the validity of two empirical regularities studied in urban economics: Zipf's law (the rank‐size rule), and Gibrat's law, or the law of proportionate growth. The main contribution of this work is the use of a new database with information on all the cities (understood as incorporated places), without size restrictions. Our results enable us to confirm that Gibrat's law holds (weakly), and that Zipf's law holds only if the sample is sufficiently restricted at the top, not for a larger sample.  相似文献   
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Copper ores recovered at the third millennium bce settlement of São Pedro, Portugal, were characterized by micro-Raman spectroscopy, micro-energy dispersive X-ray spectrometry (micro-EDXRF) and micro-particle-induced X-ray emission spectrometry (micro-PIXE). The collection shows the common presence of secondary copper minerals (malachite, pseudomalachite and libethenite) combined with iron oxyhydroxides (hematite and goethite), while arsenic-rich minerals are absent and, therefore, can be excluded as the source of arsenical copper. Overall, these copper ores suggest a primitive technology involving the exploitation of the superficial zone of ore bodies and reliant on the fortuitous finding of arsenic-rich sources to produce the arsenical copper alloy frequently present among metallic collections of the Iberian Peninsula.  相似文献   
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