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81.
Theories and data do not always fit and sometimes are sources of conflicts among scientists. This is the case of a morphological structure, the perineuronal net, which was denied on the basis of an ideological conflict between two giants of neurosciences: Camillo Golgi and Santiago Ramón y Cajal. The perineuronal net is a reticular structure enveloping many neurons. Originally reported by Golgi in 1893 and 1898 and confirmed by several authors before the turn of the century, the perineuronal net was used by Golgi to support the reticular theory of the organization of the nervous system. Ramón y Cajal, the paladin of the neuronal theory who had also observed this anatomical structure, denied its existence suggesting that it was a fixation artifact. After Cajal's statements, only a few Italian scientists continued to work in this field, and after the 1930s the perineuronal net was forgotten. Only the recent advances in histochemical and immunocytochemical technology confirmed the existence of this structure opening new fields in functional neuroanatomy and neuropathology.  相似文献   
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Fieldwork involving survey, detailed topographic mapping, and excavations in Pinhal da Serra, Rio Grande do Sul, Brazil, has revealed a highly-structured landscape revolving around funerary/ceremonial structures that began around A.D. 1000. This paper focuses on the results of detailed topographic survey of mound and enclosure complexes and their interpretation in light of southern Jê ethnohistorical and ethnographic data. We compare the architectural patterns of mortuary architecture from this study with fundamental spatial features of historic Kaingang’s social organisation, mortuary rituals and cosmogony myth. Our results suggest historical continuity in the organisation of space in cardinal directions (E–W), topography (low and high places), and in circular/concentric spatiality revealed in the southern proto-Jê mound and enclosure complexes. It is argued that small paired mound and enclosure complexes are associated with the material representation of a dual ranked opposition materialised in proto-Jê moiety cemeteries where important persona were buried.  相似文献   
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Organic (bone, antler, wood) knapping tools were undoubtedly a component of early human tool kits since the Lower Palaeolithic. Previous studies have identified pitting and the occasional presence of embedded flint flakes as important features for recognizing archaeological bone and antler percussors. However, no systematic protocol of analysis has been suggested for the study of this rare archaeological material. Here we present qualitative and quantitative results of a preliminary analysis of an experimental knapping hammer, using a novel combination of microscopy (focus variation optical microscope and scanning electron microscope), micro-CT scanning and energy dispersive X-ray spectroscopy. These imaging and analytical techniques are used to characterize use-damage from the manufacture of handaxes. This paper highlights the strengths and weakness of each technique. Use-wear on the working area included attritional bone loss, micro-striations and compaction of the outer layer of the antler matrix from repeated hitting of the beam against the sharp edge of the handaxe during knapping. Embedded flint flakes were also identified in the pits and grooves. This combination of high-resolution imaging techniques is applicable to fragile archaeological specimens, including those encrusted by sediment or encased in matrix.  相似文献   
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The St. John Hospital is part of a larger complex of buildings known as the Hospitallers Quarter, located south of the Holy Sepulchre in Jerusalem. At present, the hospital looks like an irregular volume both in height and in plan; it is covered by ten groin vaults resting on very stocky pillars. Each vault is formed by intersecting double curvature surfaces. In order to verify the effectiveness of continuous carbon fiber reinforced polymer sheets reinforcement, bonded at the extrados of vaults, laboratory tests were carried out on a 1:5 scale model, built with materials and construction techniques similar to those of the real building. Experimental tests were performed on the unstrengthened and strengthened vault. The experimental results shown that the strengthening system is able to increase the collapse load of the vault, without substantial variation of the initial stiffness.  相似文献   
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Salt crystallization in porous materials constitutes one of the major causes of decay of buildings/archaeological sites in a wide range of environments. Desalination is among the most common methodologies of conservative treatment for salt decay. However, classic desalination techniques might be not suitable for long-term conservation. During the past decade interest has been an increasing towards crystallization inhibitors as a new means of controlling crystallization damage. This study deals with the first in-field application of an environment-friendly inhibitor system— phosphocitrate (PC). In particular, the case study of the Roman mosaic of Orpheus and the Beasts in Perugia (Italy) is presented. The inhibitor is completely soluble in water or alcohol, non-toxic, and easy to apply, thus enabling its use in accordance with the volatile organic compounds emission control and safety during the conservation works. Relevant samples from control and treated mosaic areas were collected and analyzed comparatively by means of Fourier transform-infrared spectroscopy, scanning electron microscopy, and energy dispersive spectrometry to study the potential of the inhibitor system in preventing/controlling salt damage in such archaeological site.  相似文献   
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This article attempts to isolate the structural characteristics that affect the resilience of a regional economy. It focuses on the role played by related/unrelated variety and differentiated knowledge bases as drivers for regional resilience and originally explores their interdependences. Italy is the empirical setting, and Italian local labour systems the unit of analysis. Regional resilience is measured as growth of the employment rate after the Great Recession that began in 2008. Results confirm the importance of related variety and of differentiated knowledge bases as drivers for regional resilience. We found support of the creative capacity of culture argument, providing evidence that a moderate concentration in symbolic knowledge-based economic activities contributes to resilience. Synthetic and analytical knowledge-based activities provide positive and no support to regional resilience, respectively. Finally, the relatedness of the symbolic knowledge-based activities increases regional economic resilience. Some policy implications are then derived from these findings.  相似文献   
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Cutmarks found on the fossilised bones of butchered animals provide direct evidence for the procurement of meat through technological means. As such, they hold some of the oldest available information on cognitive ability and behaviour in human evolution. Here we present a new method that allows a three-dimensional reconstruction of cutmark morphology and the quantification of profile parameters. We have tested this new technique on cutmarks that were experimentally inflicted on a pig rib using a steel knife and an un-retouched flint flake at different angles. The method allows for the cross-sectional shape, the sharpness and depths of the resulting cutmarks to be quantified. The data show that knife mark sections are characterised by a V-shape or √-shape depending on the inclination of the knife. Cutmarks produced with the flint flake were less clearly defined and generally less sharp than those produced by the knife. We discuss the method's potential to provide new information on butchery technique and cognitive abilities developed by the human lineage, from the earliest tool-using hominins through to modern Homo sapiens.  相似文献   
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