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891.
The provenance of granite, basalt, and marble used in building the cruciform basilica of Abila of the Decapolis, northwestern Jordan, is investigated using chemical and petrographic techniques. The basilica is dated to the late fifth or early sixth century AD. The stones were characterized using macroscopic traits in combination with optical microscopy, X-ray diffraction, and stable oxygen and carbon isotope spectrometry. These data were compared to the published databases for marbles, granites, and basalts used in antiquity. The comparison showed that the basalts are most probably local. The islands of Marmara (Proconessos-1), Turkey, are the primary source of the white marbles, while Paros island (Paros-2), Greece, is a minor source. The source of the green Cipollino marbles is Styra in the island of Euboea (Greece). The pink and gray granites are likely microasiatic from the Çigri and Kozak Dâgs, respectively, northwest Turkey.  相似文献   
892.
The style of the contemporary German artist Anselm Kiefer is highly innovative and unconventional and is characterized by the use of diverse materials that he selects and combines according to the emotions that they stir in him. The conservation and preservation of works by Kiefer are particularly difficult tasks because of the heterogeneity and, in some cases, the incompatibility of the materials used; therefore, a thorough characterization is crucial before any intervention is considered. In this paper, we report the results of an investigation on a fragment from a multimaterial work and on samples from the paintings Bohemia Lies by the Sea and Die Größe Fracht. The large fragment was cut by the artist himself from a work in progress and is considered destitute of any artistic value; therefore, it was possible to sample it extensively. This fragment and the samples from the Die Größe Fracht and Bohemia Lies by the Sea paintings were analyzed by ultraviolet (UV) fluorescence imaging, fiber optic reflectance spectroscopy, Fourier transform infrared spectroscopy, nuclear magnetic resonance, Raman spectroscopy, X-ray diffraction, gas chromatography-mass spectrometry, and pyrolysis gas chromatography-mass spectrometry. This multitechnique approach allowed us to fully characterize and identify pigments, dyes, and organic components that reflect the diversity of the materials typically chosen by the artist. The results are evaluated in the context of the interview that Antonio Rava had with the Anselm Kiefer in 2000.  相似文献   
893.
The development of identification criteria for crop plants based on phytoliths is of high relevance for archaeology, palaeoecology and plant systematics. While identification criteria are available for major food crops, these are mostly based on phytoliths from inflorescences, while other plant parts remain undetected. This paper focuses on bilobate phytoliths from leaves of Panicum miliaceum L. (common millet) and Setaria italica (L.) P. Beauv. (foxtail millet), two taxa that co-occur in regions of Asia and Europe since prehistory and regularly occur at archaeological sites in Eurasia. Leaves of the investigated taxa were systematically sampled to explore the variation of short cells and to collect 27 morphometric variables of bilobate phytoliths with newly developed open-source software. The data was analysed by discriminant analysis, analysis of variance and multiple comparison tests. The resulting morphometric data from five populations per species enables a distinction between the bilobate phytoliths of P. miliaceum and S. italica. Observed differences between populations within species affect only few parameters. This possibility to classify populations of bilobate phytoliths from P. miliaceum and S. italica leaves offers a new method for the detection and identification of these taxa in archaeology, amongst others.  相似文献   
894.
Tools for determining the value of metal appear as symbols among grave goods in prehistoric and early medieval Europe and the Near East. Also, five boat burials excavated in eponymous Vendel contained touchstones. This article presents the results of chemical microanalyses of metal traces preserved on them and discusses the linear streaks of zinc in light of extraordinary ore deposits in central Sweden, exploited as early as the Early Middle Ages. In addition, forging tools found in four boat burials in Vendel are interpreted as symbols belonging to the funerary assemblages of ancient leaders. However, although both forging tools and tools for determining the value of metal were used in the treatment of metal, it would be misleading to search for their functional connection. They are linked in prehistoric and early medieval graves exclusively by their function as a symbol, one which they share with other objects, regardless whether exclusive or common.  相似文献   
895.
While pioneers of archaeology in any given region have established the foundations of the discipline, their views have not remained unchanged in places such as Europe, North America and Australasia. In these regions, successive generations of researchers changed the direction of their work based not just on new observations but also in light of new methods and theories. For example, the idea of a Bronze Age revolution popularised by V. G. Childe in Europe was superseded by multiple alternatives over the years. In southern African Iron Age studies, John Schofield, Gertrude Caton-Thompson, Roger Summers, Keith Robinson and Peter Garlake created an impressive platform upon which successors could build. Confronting firm disapproval from more experienced researchers in the early 1980s, Huffman speculated that the evolution of sociopolitical complexity in our region was a linear relay from Mapungubwe to Khami via Great Zimbabwe. This position was sustained as the conventional wisdom largely, we argue, because no new research was being carried out in key areas of the region, and too few students, in particular African ones, were being trained to expand the focus of investigation. Here, we present new data to support our argument, that the pathway to sociopolitical complexity in southern Africa was multilinear. We propose looking forward rather than back, and to continue to seek the exposure of scales of interaction between multiple but chronologically overlapping entities associated with the rise of sociopolitical complexity in southern Africa.  相似文献   
896.
Grass silica short cell phytoliths were sampled from the four lowermost archaeological strata in excavation 1 at Wonderwerk Cave and offer an independent record of climatic change during an episode of Early Stone Age hominin occupation at the cave. Linked to differences in growing season temperature and the geographic distribution of C3 and C4 grasses in southern Africa, fossil grass phytoliths were used to trace palaeoenvironmental shifts at the site. The results suggest that Early Pleistocene environmental conditions at the cave fluctuated: between wetter and drier summer–rainfall growing conditions (C4) towards the end of the Olduvai subchron and the beginning of the subsequent interval of reversed polarity, to mostly dry and cooler winter–rainfall growing conditions (C3), that continued throughout the interval. It ended with a shift towards increased summer rainfall aridity at around one million years ago. The fluctuation between markedly wetter and drier C4 conditions at the cave (NADP-me grass types vs. NAD-me grass types) does not support the premise that the expansion of C4 grasslands was always coupled with increased aridity.  相似文献   
897.
The discovery of Kef en-Naga site, an open-air human occupation in northeastern Algeria, was favored by a sandstone quarrying where work truncated much of the archaeological sequence on its cross-section. A multidisciplinary rescue excavation conducted on this site provided, for the first time in the region, the evidence of superimposition of two stratigraphic levels (lower and upper) of sandy clay deposits formed in humid paleoenvironmental conditions. Besides, XRD analysis show that a large amount of hematite (Fe2O3) is localized at the lower level of the stratigraphic section, where iron is found in oxide form due to the moisture. As for rock magnetic property characterization analysis, the various magnetic parameters have strong values in the upper level, and the grains are small-sized. However, various magnetic parameters are lower at the lower level and the magnetic grain concentration is reduced. Although the site is lacking faunal and carpological remains, thereby depriving us of reliable dates, the two stratigraphic levels are correlated to the Holocene according to archaeological and paleoenvironmental considerations. The lower level likely corresponding to an early Epipaleolithic culture marked by the production of microliths using a microburin blow technique, while the upper level is related to a subsequent Epipaleolithic phase, characterized by the disappearance of microburin blow technique, the dominance of an industry on flakes and the existence of pressure debitage.  相似文献   
898.
899.
900.
This article proposes a different approach to the long generation controversy that divided naturalists in eighteenth-century Europe between those in favour of preformationism, on the one hand, and supporters of the theory of epigenesis on the other. This controversy has mostly been studied through the publications of the intellectual elite, that was constituted of medical doctors, natural historians, philosophers, and theologians. Rather than reviewing the ideas and antagonisms of the direct agents of the controversy, I will attempt to approach it from the margins. What is the legacy of a long-term controversy when it seems to be over? How was such an extended controversy perceived by contemporaries that would only have a fragmented access to quarrel? What is the role of scientific disputes in the education of doctors? I will address these questions by analyzing four essays written by medical students of the Royal Medical Society of Edinburgh.  相似文献   
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