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The palaeopathological study of a large skeletal collection of Ursus spelaeus from Italy indicates that the most frequent pathologies were diseases of the teeth and jaws and this indicates that the extinction of the large European bear, in large part, can be attributable to masticatory disadaptation. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
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Estimation of age at death is an unavoidable step in the process of human identification, both in forensic practice and in the anthropological and palaeopathological study of skeletal remains. In several cases, in which medical or demographic records are completely lacking, a reliable estimation of the age at death becomes very important. Skeletal remains from archaeological contexts suffer from several biasing factors such as post-mortem changes, taphonomy and various burial practices depending on age, sex and social status of the deceased persons.  相似文献   
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Past earthquakes have shown the high vulnerability of existing masonry buildings, particularly to out-of-plane local collapse mechanisms. Such mechanisms can be prevented if façades are restrained by tie rods improving the connections to perpendiculars walls. Whereas in the past only static models have been proposed, herein the nonlinear equation of motion of a monolithic wall restrained by a tie rod is presented. The façade, resting on a foundation and adjacent to transverse walls, rotates only around one base pivot and has one degree of freedom. Its thickness is explicitly accounted for and the tie rod is modeled as a linear elastic—perfectly plastic spring, with limited displacement capacity. The model is used to investigate the response to variations of wall geometry (height/thickness ratio, thickness), tie rod features (vertical position, length, prestress level), and material characteristics (elastic modulus, ultimate elongation, yield strength) typical of historical iron. The most relevant parameter is the steel strength, whereas other characteristics play minor roles allowing to recommend reduced values for pre-tensioning forces. The force-based procedure customary in Italy for tie design is reasonably safe and involves protection also against collapse, although probably not enough as desirable.  相似文献   
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The MoVimento 5 Stelle (M5S, Five-Star Movement), led by the former comedian Beppe Grillo, is one of the political novelties of major interest in the Italian political scene, and also on an international scale. This article examines the Movement's evolution following its extraordinary success at the 2013 Italian general election. Four peculiar features of the M5S's experience are analyzed here: the Movement's anti-system stance; its specific conception of democracy; its post-ideological profile; and the innovative elements in its party organization. The overall picture suggests a mixture of resistance and adjustment to the system. Consequently, the process of gradual normalization and institutionalization of Grillo's party is becoming increasingly evident, while inherent contradictions and internal problems remain.  相似文献   
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A new robust design methodology to control the seismic performance of asymmetric structures equipped with a Single Tuned Mass Damper (STMD) is presented in this article. This design approach aims to control the seismic response of such systems by reducing both flexible-and stiff-edge maximum displacement. The dynamic problem has been investigated in the state space representation showing that the TMD works as a closed-loop feedback control action. A synthetic index to estimate the seismic performance of the main system has been defined by using H norm. Wide-ranging parametric numerical experimentation has been carried out to obtain design formulae for the STMD in order to minimize such a performance index. These formulae allow for a simple design of STMD position and stiffness to optimally control both translational and rotational motion components, whereas two mass devices are generally considered to improve the seismic performance of asymmetric structural systems The effectiveness and efficiency of the obtained design formulae have been tested by investigating the dynamic behavior of the asymmetric structure after being subjected to different recorded seismic inputs.  相似文献   
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ABSTRACT

The 2010–2011 Canterbury earthquake sequence provided extensive evidence of the significant seismic vulnerability of New Zealand unreinforced masonry (URM) churches. Given the high seismicity of the country, the exposure of human lives and the societal significance of ecclesiastic buildings, for both historical and religious reasons, the reduction in seismic vulnerability of this building type is of primary importance. By analyzing the seismic performance of a sample of 80 affected buildings, regression models correlating mean damage levels against ground-motion parameters were developed for observed collapse mechanisms, accounting for vulnerability modifiers whose influence was estimated via statistical procedures. Considering the homogeneity of New Zealand URM churches, the vulnerability models developed for the Canterbury region were extended to the whole country inventory, and a synthetic index was proposed to summarise damage related to several mechanisms. Territorial scale assessment of the seismic vulnerability of churches can assist emergency management efforts and facilitate the identification of priorities for more in-depth analysis of individual buildings. After proper calibration, the proposed approach can be applied to other countries with similar building heritage.  相似文献   
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The Museo Storico Musicale of the San Pietro a Majella Conservatory of Music in Naples owns a collection of over 200 musical instruments of considerable historical importance. Within the collection, 30 bowed and plucked instruments representative of the Neapolitan violin-making tradition were analysed dendrochronologically to date them, estimate the provenance of the wood and investigate the instruments’ construction characteristics. The values of the statistical cross-dating tests were generally high and allowed 26 instruments to be dated. In all but one case, the dates were consistent with those of the catalogue. From the perspective of wood selection, we noted an unusual use of very old spruce wood, well beyond simple seasoning. The construction technique of the soundboard and other characteristics show good similarities with instruments analysed in other Italian collections. Thus, even in Neapolitan instruments, the growth rings are smaller in small instruments and larger in cellos or double basses. In conclusion, the Neapolitan violin-making school has shown great care in the choice of wood, most coming from regions as far away as Germany or Switzerland, thus confirming the existence of an active large-scale trade in wood for the production of musical instruments.  相似文献   
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