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41.
42.
数亿年前,这些山峰努力像分娩的婴儿一样挣向天空,浮出水面得以新生;
260万年——这条不起眼的小河用这个时间长度在地球上打磨出了最不像地球景色的这片区域; 相似文献
43.
Gas chromatography (GC), GC-mass spectrometry (GC-MS) and GC-combustion-isotope ratio MS (GC-C-IRMS) analyses of absorbed and surface lipid residues preserved in potsherds were used to explore the extent of pig product processing exploitation in the later British Neolithic Grooved Ware tradition. Assessments were made regarding whether porcine lipids were associated with specific Grooved Ware traits, i.e. decoration, substyle, geographical area and type of site. Two hundred and twenty-two Grooved Ware potsherds were analysed, 70% of which contained lipid concentrations considered significant (>5 μg g−1). All the lipid residues were dominated by animal fats, although plant and beeswax were also detected in a small number of extracts. δ13C values of the major fatty acid components of degraded animal fats (C16:0 and C18:0) were determined for 126 extracts and used to assign ruminant or porcine origins to the residues; 16% of these were found to have a predominantly porcine isotope signature. Statistical associations with pig exploitation were shown to exist with substyle, geographical area and site type, whereas, no relationship was seen between decoration and the type of commodity processed. Intact triacylglycerols were preserved in 19% of the sherds; half of these had distributions consistent with the identifications based on δ13C values, the remainder differed either due to the presence of mixed commodities or because lower molecular weight homologues had been lost due to degradation. In addition to the detection of pig exploitation, results from lipid residue analysis showed a good correlation with faunal assemblages, suggesting that stable isotope analysis may be used as a proxy for animal exploitation at sites where bones have not survived. 相似文献
44.
This paper presents a method for estimating edge length from flake dimensions. Comparison of estimated values with data from measured flake edges demonstrates the robusticity of the method. Building on the work of Braun (Braun, D.R., 2005. Examining flake production strategies: examples from the Middle Paleolithic of Southwest Asia. Lithic Technology 30, 107–125; Braun, D.R., Harris, J.W.K., 2003. Technological developments in the Oldowan of Koobi Fora: innovative techniques of artifact analysis and new interpretations of Oldowan behavior, in Mora, R., de la Torre, I. (Eds.), Oldowan: Rather More than Smashing Stones. Treballs d’ Arqueologia 9, pp. 132–144) this estimate is used to generate an edge length to mass value for complete flakes—taken to be a proxy for flaking efficiency. It is shown that this value is useful in tracking the onset, variability and decline of a well known technological phase—the Howiesons Poort of South Africa. The results suggest that the Howiesons Poort was a time in which flaking efficiency was emphasised. Furthermore, comparison of upper limits of edge to mass values for different raw materials may provide an insight into changes in raw material selection. 相似文献
45.
Jérôme Wilson 《European Review of History》2002,9(2):223-239
La naissance de la Banque centrale européenne a suscité une discussion soutenue à propos des critères de convergence, de l'objectif d'inflation et de la flexibilitédes taux de change de l'euro par rapport aux autres monnaies-clés (dollar, yen). Un détour par les arrangements et unions/désunions monétaires passés s'avère pertinent en termes d'information à propos des conditions essentielles pour l'établissement et la gestion des politiques monétaires, non seulement du point de vue économique mais également du point de vue politique. Les lec¸ons principales qu'apporte l'Histoire indiquent que: inflation et taux de change constituent deux 'ancres', parmi d'autres, choisies en fonction d'une orientation idéologique plus marquée qu'il n'apparâ L t au premier abord; qu'àla fois les créditeurs et les débiteurs nets doivent être responsabilisés pour organiser un système durable; que l'intégration du marchéa toujours précédél'union monétaire; enfin, qu'un lien solide entre pays apporte une meilleure protection contre les chocs extérieurs qu'un ensemble de réactions individuelles non coordonnées. Néanmoins, une question importante reste en suspens: est-il possible pour une union monétaire de supporter la présence de parasites monétaires dans sa périphérie, hôtes indésirables qui ne participent pas au partage des coûts engendrés par l'union monétaire, mais qui s'invitent au sein du système et en profitent àtravers des alignements tacites sur la politique appliquée àla monnaie unique? 相似文献
46.
This paper explores the reasons why cities are often major centres of innovation, even in some less favoured regions and countries. It starts with an anatomization of the dominant factors that explain why key less favoured settings developed 'new economy' clusters through institutional interaction with Silicon Valley. The analysis concludes that public research resources and private commercialization funding are central, supported by a wide array of private but few public innovation support services. It then examines a number of cases from cities in less favoured regions and countries where innovation has occurred. The conclusions are that the research-venture capital model is present and explains innovation in each case. However, in some cases public venture capital has to substitute for private due to market failure, or a phenomenon termed 'Silicon Valley Offshore' has been induced. Cities are innovative where they concentrate the desired scientific and investment knowledge capabilities. 相似文献
47.
48.
Alex Law 《Geografiska annaler. Series B, Human geography》2005,87(4):267-277
In this paper, the conception of .Great Britain. — a wholly unsatisfactory nomenclature — as an island nation is examined. In this case, a relatively small land mass acted as an originary point of departure for outward‐bound Great Power projections across the open spaces of seas. This paper further explores the varied implications for nationalism within Britain of the diverse island ‘roots’ of the British navel and the ‘routes’ of British navalism. Three themes recur in the popular mobilization of British maritime island nationalism: the besieged island, the island as universal exemplar of civilization, and the navy as national protector. Some consideration is given to the significance of island symbols such as Britannia as a marker of the fate of great island nationalism. 相似文献
49.
Matt A. White Alex G. Cook Scott A. Hocknull David A. Elliott 《Alcheringa: An Australasian Journal of Paleontology》2013,37(4):435-441
WHITE, M.A., FALKINGHAM, P.L., COOK, A.G., HOCKNULL, S.A. & ELLIOTT, D.A., 2013. Morphological comparisons of metacarpal I for Australovenator wintonensis and Rapator ornitholestoides: implications for their taxonomic relationships. Alcheringa 37, 1 - 7. ISSN 0311-5518.Various comparisons of left metacarpal I of the Australovenator wintonensis holotype have been made with Rapator ornitholestoides. These specimens were identified as being morphologically more similar than either was to that of the neovenatorid Megaraptor namunhuaiquii. Owing to the poor preservation of A. wintonensis and R. ornitholestoides, distinct morphological separation between the two appeared minimal. The recent discovery of a near perfectly preserved right metacarpal I of A. wintonensis enables a direct and accurate comparison with R. ornitholestoides. Distinct morphological differences exist between the metacarpals of the two species. A re-evaluation of the age of the A. wintonensis holotype site (AODL 85 ‘Matilda Site’) with zircon dating reveals a maximum age of 95 Ma, 10 Ma younger than the Griman Creek Formation at Lightning Ridge, from which R. ornitholestoides was recovered. This age difference detracts from the probability that the specimens belong to the same genus.Matt A. White? [fossilised@hotmail.com], School of Engineering, The University of Newcastle, Callaghan, New South Wales 2308, Australia; Peter L. Falkingham? [pfalkingham@rvc.ac.uk], Department of Comparative Biomedical Sciences, Structure and Motion Laboratory, Royal Veterinary College, London, UK; Alex G. Cook [alex.cook@y7mail.com] and Scott A. Hocknull [scott.hocknull@qm.qld.gov.au], Ancient environments, Queensland Museum, Hendra, Queensland, 4011, Australia; David A. Elliott [david.elliott@aaod.com.au], Australian Age of Dinosaurs Museum of Natural History, The Jump Up, Winton, Queensland, 4735, Australia. ?Also affiliated with Australian Age of Dinosaurs Museum of Natural History, The Jump Up, Winton, Queensland 4735, Australia. ?Also affiliated with Department of Ecology and Evolutionary Biology, Division of Biology and Medicine, Brown University, USA. Received 22.9.2012; revised 13.1.2013; accepted 17.1.2013. 相似文献
50.