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21.
Pierre Morzadec Mohammad Dastanpour Anthony J. Wright 《Alcheringa: An Australasian Journal of Paleontology》2013,37(1):143-149
The discovery of two new Frasnian species of the subfamily Asteropyginae, Bradocryphaeus kermanensis and Radiopyge hamedii, in the Haruz section north of Kerman, east-central Iran, demonstrates for the first time the presence of North Gondwanan trilobites in this region. The two new species provide a link between faunas from Afghanistan to the east and the Alborz Mountains in north Iran. The recognition of R. hamedii confirms the validity of Radiopyge Farsan, hitherto known only from Afghanistan, as well as the presence in some Frasnian Asteropyginae of six pairs of lateral pygidial spines. 相似文献
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While much recent thinking about city administration suggests tinkering with attitudes of administrators, it will be useful to review how administrators and officials encounter deeper social forces: the continuing inequalities and separations of race and class. Cases of "progressive government" experience—in Chicago; Boston; Berkeley; Santa Monica; Burlington, Vermont; and elsewhere—and of community development institutions spread more broadly through US. cities, suggest the outlines of new challenges and response by urban administrators and politicians. 相似文献
26.
Pierre Therrien 《European Planning Studies》2005,13(6):853-877
The objective of this paper is to assess whether establishments' innovation performance and innovation strategies differ by the size of the city in which they are located. Using the Canadian 1999 Survey of Innovation database (establishment-based), it was found that the rate of innovation is not correlated with city-size, but when the innovation measure takes into account the importance of innovation, then the size of the city does matter. The results show that establishments belonging to smaller cities (with populations of less than 50,000) are less likely to be associated with a world-first innovation than those located in larger cities. Four innovation strategies have been retained—Private Source, R&D, Collaboration and Public Science Base paths—and the results show that the R&D path leads to the greatest increase in the estimated probability to be associated with a world-first innovation, for almost all sectors and all city sizes. 相似文献
27.
Marie‐Laurence De Keersmaecker Pierre Frankhauser Isabelle Thomas 《Geographical analysis》2003,35(4):310-328
The objective of this paper is to compare fractal‐based parameters calculated by different fractal methods for urban built‐up areas and to link the observed spatial variations to variables commonly used in urban geography, urban economics, or land‐use planning. Computations are performed on Brussels, Belgium. Two fractal methods (correlation and dilation) are systematically applied for evaluating the fractal dimension of built‐up surfaces; correlation is used to evaluate the fractal dimension of the borders (lines). Analyses show that while fractal dimension is ideal for distinguishing the morphology of Brussels, each estimation technique leads to slightly different results. Interesting associations are to be found between the fractal dimensions and rent, distance, income, and planning rules. Despite its limitations, fractal analysis seems to be a promising tool for describing the morphology of the city and for simulating its genesis and planning. The model is robust: it replicates the urban spatial regularities and patterns, and could hence fruitfully be integrated into intra‐urban simulation processes. 相似文献
28.
Ludovic Slimak Jason E. Lewis Evelyne Crégut-Bonnoure Laure Metz Vincent Ollivier Pierre André Julia Chrzavzez Yves Giraud Marcel Jeannet Frédéric Magnin 《Journal of archaeological science》2010
Le Grand Abri aux Puces (GAP), located on the right bank of the Ouvèze River of southern France, has been known to contain well-preserved stone tools and faunal remains, but our work in 2008 was the first professional, controlled excavation at the site and has exposed at least 1 archaeological layer with a very rich and diverse faunal assemblage (23 macrofaunal species, as many for the microfauna, 27 land snail species), abundant charcoals (fragments are large and preserve small twigs with their pith and bark still intact), and stone tools with immaculate surface preservation (retaining their original freshness and preserving microscopic use wear). The information issuing from paleontology, micropaleontology, malacology, and anthracology all place the principle GAP human occupation unambiguously in a temperate climatic phase. Different biometric and biochronological characters of the fauna converge to place the layers found thus far from before the last glacial, and most likely in MIS 5e (127–117 kya). The lithic elements, mainly composed of tools of superior quality, demonstrating particular technical investment, and made from widely distributed raw material sources, lead us to hypothesize brief passages of hunting groups in the cave focused around an anticipated activity. This hypothesis will be refined and tested during further excavations. 相似文献
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Pauline Burger Armelle Charrié‐Duhaut Jacques Connan Pierre Albrecht Michael Flecker 《International Journal of Nautical Archaeology》2010,39(2):383-386
The 9th‐century‐AD Belitung wreck was discovered in 1998 in the Java Sea. Construction techniques rapidly confirmed that it was unlike any known Chinese or Southeast Asian vessel. The uncertainty about its origins was resolved in 2008 by timber identifications: it was constructed in the Middle East (probably Oman or Yemen). This paper, on the characterization of a dammar resin lump collected in the vicinity of the wreck, supplies additional evidence confirming the probable re‐stitching of the vessel somewhere in Asia. © 2010 The Authors 相似文献
30.
Erwan Messager Aïcha Badou François Fröhlich Brigitte Deniaux David Lordkipanidze Pierre Voinchet 《Archaeological and Anthropological Sciences》2010,2(1):25-34
Mineralised fruits and seeds are frequently found in archaeological sediments but their chemical nature has not been often
examined. The nature and the origin of these archaeobotanical remains have to be investigated to understand their taphonomic
history. Fruits or seeds can be mineralised not only by replacement mineralisation but also by biomineralisation during the
plant life. The mineral components of three fossil fruits sampled on the Pleistocene site of Dmanisi were analysed and compared
with their modern analogues. Analyses were carried out by means of an environmental scanning electron microscope, equipped
with an energy dispersive X-ray device and by means of a Fourier transform infrared spectrometer. Biogenic carbonates and/or
biogenic silica were identified in the fossil and modern fruits of some taxa. Comparison between fossil and modern specimens
has shown that molecular reorganisation occurred in carbonate and in biogenic silica during fossilisation, through diagenetic
processes. The resulting stable mineral structures confer an exceptional preservation to fruits in sediments. Taking into
account these taphonomic specificities (transformation and differential preservation), the chronological and palaeoenvironmental
aspects of the mineralised fruits are discussed. 相似文献