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Although resection of cervical “chondromas” had been reported since the late twenties, the true nature of this condition was not recognized at that time. This paper reports a case of “inferior cervical radiculitis by herniation of nucleus pulposus” operated by Prof. Angelo Chiasserini Sr, one of the founders of Italian neurosurgery, in January 1937. To our knowledge this represents one of the first examples of correct etiopathogenetic interpretation of cervical disc disease. Surgery was followed by excellent recovery, a quite remarkable result in those times. The case history is reported in detail, and a short historical sketch of cervical disc disease is depicted.  相似文献   
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Herding and farming coexisted in Central Asia for several thousand years as main options of preindustrial economic production. The relationship between people practicing different variants of these modes of subsistence is known to have been dynamic. Among the many possible explanations, we explore this dynamic by modeling mechanisms that connect aggregate decisions to land use patterns. Within the framework of the SimulPast project, we show here the results from step 1 of our modeling program: the Musical Chairs Model. This abstract agent-based model describes a mechanism of competition for land use between farming and herding. The aim is the exploration of how mobility, intensity, and interdependence of activities can influence land use pattern. After performing a set of experiments within the framework of this model, we compare the implications of each condition for the corroboration of specific land use patterns. Some historical and archaeological implications are also discussed. We suggest that the overall extension of farming in oases can be explained by the competition for land use between farming and herding, assuming that it develops with little or no interference of climatic, geographical, and historical contingencies.  相似文献   
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Enzo Melandri represents an atypical route in Italian epistemology. Critic of neopositivism, he studied the relations between symbolic formations of theories and actual experience via the concept of schematism. He aimed to reincorporate science into the totality of praxis by articulating a phenomonology and archeology of knowledge. Epistemology thus becomes a meditation on the meaning of scientific reason and on its links to society.  相似文献   
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Percussive activities are highly relevant in the economy of modern hunter-gatherer societies and other primates, and are likely to have been equally important during the Palaeolithic. Despite the potential relevance of percussive activities in the Early Stone Age, attempts to study battered artefacts are still rare. In order to establish protocols of analysis of battered tools, this paper pursues an interdisciplinary approach combining techno-typological, refit, use-wear and GIS studies of experimental anvils from Olduvai Gorge (Tanzania). The main aim is to classify types of damage on battered artefacts according to the percussive task performed, and hence identify patterns that can be used to interpret the Oldowan and Acheulean evidence. Our results indicate that abrasion marks on anvil surfaces are typical of nut cracking, while bone breaking leaves characteristic scars and abrasion marks on the edges of anvils. Pounding of soft materials such as meat and plants also causes battering of anvils, producing morphological and spatial patterns that can be discerned from the heavy breakage of anvils during bipolar flaking. By integrating macroscopic, microscopic and spatial analyses of experimental stone tools, this paper contributes to create a referential framework in which Early Stone Age battered artefacts can be interpreted.  相似文献   
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An artificial layered sandy site was created using a combination of native sand and colored sand (3 parts native uncolored quartz, 1 part colored quartz) in Apalachicola National Forest near Tallahassee, Florida. Twelve layers of sand, each 1 by 1 m in horizontal extent by 10 cm in thickness were emplaced to a depth of 2 m followed by implantation at the surface of a Florida harvester ant (Pogonomymrex badius) colony (the lower two layers were 50 cm thick). The colony excavated a nest, and after 7 months, the sand layers were excavated to the base to test the hypothesis that sand grains were moved upward within the ant nest without reaching the surface. The ants penetrated 11 of the 12 colored layers reaching a depth of 130 cm. Thirty nine sticky-acetate peels of ant chamber floors were collected and colored sand grains were counted under a microscope. More than 16,000 grains were identified in layers that did not originally host them. Of these, more than 80% were unambiguously moved upward. This means that possibly as many as 54,000 upwardly mobile grains were present (ratio of 3:1 uncolored to colored). In relation to optical luminescence (OSL) dating, this means that grains that would not have been optically zeroed by transport to the surface (defined here as subterranean-transported) were present in abundance, and that if the site was ancient, there would have been found many grains that were older than the layers they presently reside in, even if only one colony of harvester ants had disturbed the layers. This is in addition to the fact that backfilling of chambers and tunnels may contribute even more significantly to the presence of a subterranean-transported component of an OSL sample. We conclude that ants can significantly affect the age distributions in sandy archaeological sites. Multiple examples of such disturbances have been documented in the literature. Most relevant to our results are recent studies of the OSL chronology of Pre-Clovis-age and Palaeoindian age archaeological sites in sandy environments in North America that may have been compromised by ant bioturbation of quartz sand grains. Here we have examined in detail the potential effects of one episode of ant nest-building on the age overestimation of affected sediments. From this we found that as few as 12 episodes of bioturbation involving backfilling of chambers in the same volume of sand could lead to the presence of 1 contaminant grain per 50 grains of sample.  相似文献   
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Palynofloras from an outlier of Tertiary sediments in the One Tree Hill area north of Adelaide are nonmarine and correlate with similar assemblages from Middle Eocene North Maslin Sands from Maslin Bay and Golden Grove. Although there are similarities with time-equivalent Lower Nothofagidites asperus Zone palynofloras in the Gippsland Basin, a number of species in the South Australian palynofloras do not extend below the Late Eocene in the Gippsland sequences. This indicates earlier appearances for these species in southcentral Australia. The sediments overlie a highly weathered bedrock palaeosurface, indicating that a phase of significant weathering occurred prior to the Middle Eocene. A number of selected taxa are illustrated and their distribution in the palynofloras is discussed. Two new species, Proteacidites mildenhallii and Proteacidites parrawirrensis, are described and one species, Rhoipites byfieldensis, is emended.  相似文献   
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