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11.
A relevant subject of study in the sphere of ancient Egyptian painting technology is given by the evolution of the palette across New Kingdom, Ptolemaic and Roman periods. Functionally to secondary factors such as geographic occurrence of minerals and type of associated surface, the employment of certain painting materials provides relevant insights into particular issues such as relative dating of the object and social rank of the owner. The Book of the Dead of Amenemhet (ROM 978 × 43.1, middle Ptolemaic Period) has been analysed at the Department of Restoration and Conservation of Archivals, Graphics and Book Illumination of the Cologne Institute of Conservation Sciences (Germany). Together with visible reflectance spectroscopy, digital and optical microscopy, devices such as XRD, SEM-EDX and FT-IR have been successfully employed for the characterization of the pigments from the polychrome funerary papyrus displayed at the Royal Ontario Museum, Toronto (Canada). The present research took place within a series of investigations performed at the CICS, devoted to the interdisciplinary study of funerary Egyptian papyri dating from the early 18th Dynasty onwards.  相似文献   
12.
This article examines the flexibility of the notabile model in different circumstances and time periods. The idea of a notabile cannot be restricted to only a few cases as there are many examples of notabili who, despite not having social and family origins of the classical notabile type, tend to assume the same behavioural and cultural patterns in managing power. The patterns usually considered typical of a notabile are often linked to landed property and the professions, but there are many other cases that suggest that the qualities of the notabili change in different historical and political moments, and are easily adapted to changing social and environmental circumstances. Even when they do not seem to fit directly into the classical model, over time those original features are still evident.  相似文献   
13.
The aim of this article is to understand the triggering factors of new firm growth in high-tech environments (life science, knowledge-intensive business services [KIBS] and engineering) by studying a representative sample of high-growth Italian start-ups. Our empirical research uses the information gathered during direct interviews with managers through a semi-structured questionnaire, which was presented to 382 new Italian firms. Considering the characteristics of new firms, this article summarizes the key growth factors. Investment in acquiring new competencies both in technology and marketing, development of dynamic capabilities (investment in human resources and new routines) and access to external knowledge and information sources emerged as significant.  相似文献   
14.
Waterlogged archaeological wood undergoes decay processes that depend on both the burial conditions and the constituting species, and which cause the depletion of the structural components of wood cells. To quantitatively assess the state of preservation of the decayed material, specific parameters are usually measured by means of both chemical and physical analyses. In this paper an innovative approach in the use of the data obtained from these kinds of measurements is developed. A series of 132 archaeological wood samples of different wood species, burial times and states of preservation, and coming from different sites in Italy, was analysed. Their residual chemical composition, maximum water content and basic density were measured, and a reasoned use of these parameters was carried out through their elaboration, with the aim of both evaluating eventual incongruence or anomalies in the raw physical and chemical data (which has never been accomplished so far) and directly comparing in a reliable way the analytical results obtained from archaeological samples with very different states of preservation. This approach allowed defining the effective values of chemical parameters related to wood decay according to a same reference basis of calculation among the various data. By this way, it was possible to state that lignin can be also attacked by the agents causing biotic decay, and that in hardwoods its decay is more related to the burial conditions than to the wood species. Instead, the mechanism of polysaccharide depletion is diversified: conifers showed a uniform behaviour whereas hardwoods were more species-dependent. Moreover, in addition to the chemical composition, also anatomical factors influence the carbohydrate rate of decay in waterlogged wood.  相似文献   
15.
The nonlinear seismic response of base-isolated framed buildings subjected to near-fault earthquakes is studied to analyze the effects of supplemental damping at the level of the isolation system, commonly adopted to avoid overly large isolators. A numerical investigation is carried out with reference to two- and multi-degree-of-freedom systems, representing medium-rise base-isolated framed buildings. Typical five-story reinforced concrete (RC) plane frames with full isolation are designed according to Eurocode 8 assuming ground types A (i.e., rock) and D (i.e., moderately soft soil) in a high-risk seismic region. The overall isolation system, made of in-parallel high-damping-laminated-rubber bearings (HDLRBs) and supplemental viscous dampers, is modeled by an equivalent viscoelastic linear model. A bilinear model idealizes the behavior of the frame members. Pulse-type artificial motions, artificially generated accelerograms (matching EC8 response spectrum for subsoil classes A or D) and real accelerograms (recorded on rock- and soil-site at near-fault zones) are considered. A supplemental viscous damping at the base is appropriate for controlling the isolator displacement, so avoiding overly large isolators; but it does not guarantee a better performance of the superstructure in all cases, in terms of structural and non structural damage, depending on the frequency content of the seismic input. Precautions should be taken with regard to near-fault earthquakes, particularly for base-isolated structures located on soil-site.  相似文献   
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Varia     
This article opposes the view (propounded recently by O'Hara on the basis of Austin) that there is a calculated ambiguity in Aen. 1, 286–296, to the effect that Caesar the Dictator is as relevant for the interpretation as Augustus. Asserting that Vergil refers only to the latter the present author discusses particular problems, tries to elucidate the underlying historical situation and identifies it specifically with the very beginning of the principate (29 B.C.) showing i.a. that the Parthian question is not pertinent.  相似文献   
18.
Reported here are the results of a mortality analysis of an Ursus spelaeus death assemblage from Grotta Lattaia, southern Tuscany (central Italy), excavated in 1939. The Grotta Lattaia cave bears are among the latest representatives of the species. The large amount of cave bear remains indicates that the cavern was a lair for hibernating bears which repeatedly, but not necessarily yearly, occupied it. The mortality evidence indicates that deaths occurred primarily during hibernation from violent predation, and, therefore, that the bears had direct interaction with other carnivores. However, no sign of interrelation with humans could be found, even though Middle Paleolithic human remains and tools had been recovered associated with the bear material. Grotta Lattaia can be thus considered an example of cumulative, non-human-caused violent deaths in a hibernation context.  相似文献   
19.
当今,无论在研究领域还是教学领域,世界历史都成为最重要的议题之一。人们可以真切地感受到有关世界体系的历史研究取得了长足发展。这一新趋势削弱了传统的中、小学历史教学,传统历史教学建立在种族中心主义方法基础之上,被民族国家用于加强民族集体认同(通常与其他国家相对立)。与此相反,新的世界历史教学可以被视为一种开展不同文化间教育和加强世界主义的手段。这里建议世界历史课程计划以概念、空间和时间这三重框架为基础。概念框架集中于两个主题:人类社会的演进及其相互交往;空间框架可以持续利用与主题有关的球体投影图来展示;时间框架由基于9个时代的历史分期连接起来,另附一个时期论述未来前景。  相似文献   
20.
The determination of the chemical composition of different parts of wall paintings (pigments, mortars and binders) provides information about technology of preparation of an artefact. Herein, we present a multi-methodological characterisation of wall paintings from a Roman archaeological site in Cuma, focusing on differences between an indoor (domus) and outdoor fabrication (a temple, Tempio con Portico (TCP)). Both pigments, binders and mortars were studied via a combination of destructive/μ-destructive (mass spectrometry, ionic chromatography, ICP-based techniques) and non-destructive (Raman microscopy, small-angle neutron scattering (SANS) and X-ray diffraction) methodologies. Particularly, the systematic presence of dolomite only in mortars from TCP may suggest an intentional use of such limestone for the outdoor fabrication of public interest. Differences between TCP and domus are also related to the composition of the pigment binder. In particular, the detected binders (studied by LC-MS/MS and GC-MS) were proteinaceous in the case of domus (possibly egg and animal glue) and drying oils in the case of TCP. Ultimately, our multi-methodological study provides an overall picture of the material components of paintings from fabrications with different use, proposing a hypothesis on technological choices according to conservative and destination reasons.  相似文献   
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