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71.
The revolution in the foundations of physics at the beginning of the twentieth century suggested to several of its most prominent workers that biology was ripe for something similar. In consequence, a number of physicists moved into biology. They were highly influential in initiating a molecular biology in the 1950s. Two decades later it seemed to several of these migrants, and those they had influenced, that the major problems in molecular biology had been solved, and that it was time to move on to what seemed to them the final problem: the nervous system, consciousness, and the age-old mind-body problem. This paper reviews this "double migration" and shows how the hopes of the first generation of physicist-biologists were both realized and dashed. No new physical principles were discovered at work in the foundations of biology or neuroscience. On the other hand, the mind-set of those trained in physics proved immensely valuable in analyzing fundamental issues in both biology and neuroscience. It has been argued that the outcome of the molecular biology of the 1950s was a change in the concept of the gene from that of "a mysterious entity into that of a real molecular object" (Watson, 1965, p.6); the gates and channels which play such crucial roles in the functioning of nervous systems have been transformed in a similar way. Studies on highly simplified systems have also opened the prospect of finding the neural correlatives of numerous behaviors and neuropathologies. This increasing understanding at the molecular level is invaluable not only in devising rational therapies but also, by defining the material substrate of consciousness, in bringing the mind-body problem into sharper focus.  相似文献   
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Calcareous nannofossils—very small‐scaled marine microfossils—occur in many archaeological materials. Foremost, these include limestones used in masonry, material which has not experienced significant modification by humans. Poorly documented are nannofossils in mortars, because the burning process of quicklime requires the heating of the raw material to > 800°C. Here we focus on calcareous nannofossils in mortar and mortar‐based samples of four medieval buildings in northern Germany. The study documents the presence of nannofossils in historic mortars. It supplies evidence for the provenance of the mortars used, thereby introducing a new tool for mortar provenance studies.  相似文献   
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Medieval pottery from excavations at Novo Brdo, Serbia, an important mining and trading centre during the 14th and 15th centuries, was investigated by a combination of optical microscopy, inductively coupled plasma – optical emission spectrometry, Fourier transform infrared, micro‐Raman and energy‐dispersive X‐ray fluorescence spectroscopy and X‐ray powder diffraction methods in order to determine its composition and firing temperature. The samples investigated were made of medium‐ to coarse‐grained, non‐calcareous clay, by a relatively well‐controlled firing procedure in an oxidizing atmosphere. The firing temperature was estimated to be 850–950°C. The similarity between the chemical composition of the investigated pottery and the local raw clay, combined with the outward appearance and the archaeological findings, indicate domestic production. The pottery is covered with the transparent lead‐rich glaze. Iron and copper were used as colourants.  相似文献   
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A coated Roman iron coin from Villa Loig in Salzburg, Austria was investigated. The coating is a copper alloy consisting of Cu, Pb, Sn, Zn and negligible amounts of Ag, a variant of gunmetal known as ‘leaded red brass’. The numismatic term for such a coin is subferratus (Latin). From an archaeometallurgical point of view, information about the chemical composition, the microstructure and the manufacturing technique are of interest. To achieve these objectives, different analytical techniques and metallographic examinations were applied. Droplet‐shaped iron inclusions were observed in the red brass coating, while at the grain boundaries, inside the iron core, copper and lead were detected (liquid metal embrittlement). The dendritic microstructure of the coating, the spheroidal‐shaped iron inclusions in the coating and the liquid metal embrittlement show that the iron coin was plated by immersing it in a molten copper alloy. The iron core is a low‐carbon steel with slag stringers, both of which are characteristic of a bloomery iron. Deformation twins (Neumann lines) were observed in the microstructure of the iron core and indicate that the coining was performed after the flan was cooled.  相似文献   
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Midcontinental pipestone quarries in Missouri, Minnesota, Wisconsin, Illinois, Ohio, and Kansas were utilized by a number of native cultures from 5000 YRBP through historic times. Except for Gunderson’s pioneering work on catlinite, the mineralogy of these sources was poorly understood until recently. For fifteen years, a University of Illinois team of archaeologists and geologists has used well-established mineralogical methods (X-ray diffraction [XRD] and reflectance near-infrared spectroscopy [NIS]) to identify and characterize nine pipestone quarries and match sources with archaeological artifacts from major Hopewell and Mississippian culture sites. NIS analyses of raw materials from nine major pipestone quarries show distinct mineralogical differences between sources but relatively uniform composition within each source. The major distinguishing minerals estimated from NIS spectra match very well with earlier results from XRD and inductively-coupled plasma (ICP) analyses. Results demonstrate that NIS is a reliable non-destructive technique for discriminating between midcontinental pipestones and for sourcing pipestone artifacts.  相似文献   
78.
Abstract

This is the first installment of a two part study examining scepticism and irinic correlations in the joy statements of Qoheleth. In this article, a synoptic overview of scepticism is provided from Pyrrho to Descartes, Hume and Kant. The article then examines scepticism's methodology and provides a working definition followed by a critical assessment of the above. The article then examines both the general views of a sceptical tradition in the Hebrew Bible and Dell's specific view of scepticism in the Book of Job followed by a critical assessment of them. Finally, a conclusion is provided for this article.  相似文献   
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