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Middle Egypt provides a unique insight into the organization of power, politics, economy, and culture at the turn of the third millennium BC. The apparently easy integration of this region into the reunified monarchy of king Mentuhotep II (2055–2004 BC) was possible because the interests and the local lineages of potentates were preserved. Trade and access and/or control of international exchange networks were important sources of wealth and power then. And Middle Egypt appears as a crossroads of diverse populations, as a hub of political and economic power, as a crucial node of exchanges through the Nile Valley, and as a power center whose rulers provided support to the monarchy in exchange of local autonomy and considerable political influence at the Court. In the new conditions of early second millennium, potentates from Middle Egypt succeeded in occupying a unique advantageous position, not matched elsewhere in Egypt, because of the concentration of wealth, trade routes, new technologies, political power, and autonomy in the territories they ruled.  相似文献   
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The phenomenon of equifinality complicates behavioral interpretations of faunal assemblages from contexts in which Pleistocene hominins are suspected bone accumulators. Stone tool butchery marks on ungulate fossils are diagnostic of hominin activities, but debate continues over the higher-order implications of butchered bones for the foraging capabilities of hominins. Additionally, tooth marks imparted on bones by hominins overlap in morphology and dimensions with those created by some non-hominin carnivores, further confounding our view of early hominins as meat-eating hunters, scavengers or both. We report on the manual/oral peeling of cortical layers of ungulate ribs as taphonomically diagnostic of hominoid/hominin meat- and bone-eating behavior that indicates access to large herbivore carcasses by hominins at the site of BK, Olduvai. Supporting these inferences, we show that certain types of rib peeling damage are very rare or completely unknown in faunas created by modern carnivores and African porcupines, but common in faunas modified by the butchery and/or consumption activities of modern humans and chimpanzees, during which these hominoids often grasp ribs with their hands, and then used their teeth to peel strips of cortex from raggedly chewed ends of the ribs. Carnivores consume ungulate ribcage tissues soon after kills, so diagnostic traces of hominin butchery/consumption on ribs (i.e., peeling and butchery marks) indicate early access to ungulate carcasses by BK hominins. Tooth marks associated with the peeling and butchery marks are probably hominin-derived, and may indicate that it was not uncommon for our ancestors to use their teeth to strip meat from and to consume portions of ribs. Recognition of rib peeling as a diagnostic signature of hominoid/hominin behavior may also aid the search for pre-archaeological traces of hominin meat-eating.  相似文献   
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Abstract

Through a critical consideration of recent proposals urging the use of “citizen forums” or “mini-publics” on issues involving science, this article reflects on the challenge posed to democracy and democratic decision making by the intellectual authority of modern science. Though the danger of a descent into technocracy is real and pressing, arguably the most serious challenge to democracy today, these novel “deliberative democratic” institutions are unpromising as a corrective beyond the local level, and may actually exacerbate the problem. The article concludes with a consideration of alternatives.  相似文献   
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A significant proportion of the Paris metro tunnels comprise a masonry vault built out of stone blocks and mortar joints, and sidewalls and slabs made of unreinforced concrete. In order to provide the necessary data for future structural evaluation, an extensive laboratory testing programme has been conducted to characterize the materials of the tunnel separately, i.e., mortar, stone, and concrete. The tests, carried out on specimens taken from cores extracted from a 1930s tunnel, enabled to determine the mechanical properties, including direct tensile, shear strength, and mode I fracture energy, as well as the properties of the stone-mortar interface. Results show that the masonry mortar joints could reach 10 cm in width, and that blocks of stone varied in composition and porosity, thus producing a wide range of mechanical properties. The concrete was composed of large-sized aggregates and showed low stiffness and strength. Based on these experimental results, ratios between mechanical characteristics are hereby proposed. Perspectives on the use of this experimental data in a finite element model are then discussed.  相似文献   
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