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61.
A group of Roman glass objects from the Bocholtz burial in the SW of Limburg (The Netherlands) was found to have been subject to varying degrees of degradation. Many of the 25 colourless glass objects were fragmented to pieces <0.1 cm (“sugared”), whereas the three transparent blue-green glass objects were in near-pristine state. Analyses using SEM, XRF and EDS revealed that the fragmentation was the direct result of the intense leaching of Na2O from the glass structure and its replacement with water. The resulting gel layers with low-Na2O contents and large amounts of water are sensitive to cracking when they dry out. Thin-walled glass appears to be less sensitive to cracking from the resulting stress than thick-walled glass. Local differences in the moisture regime during burial also influence the severity of the glass degradation. Glass with low concentrations of CaO seems to be the most sensitive to this form of degradation. The typical blue-green Roman glass is less sensitive as it generally has considerably higher concentrations of CaO. 相似文献
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Christopher van der Krogt 《The Journal of religious history》1998,22(3):320-335
The Catholic campaign against contraception in New Zealand during the 1930s is usually interpreted from the perspective of the promoters of birth control, who accused the church of exercising undue influence over the Labour government (1935–49). This paper argues that while Catholics were the most outspoken opponents of contraception, their opposition to the dissemination of birth control information and contraceptive devices was shared with other influential groups, notably the Protestant churches, the medical profession, journalists, and politicians. It was the combined strength of these conservative interests, not pressure from Catholics alone, which discouraged the Labour government from establishing birth control clinics. Catholics and many other New Zealanders feared that increased access to contraceptives would reduce the birth rate, leaving New Zealand vulnerable to non-British migration or even invasion. There was also widespread concern that the promotion of birth control would encourage sexual promiscuity. Since Catholics sought a compete ban on artificial contraception, however, they were unable to cooperate with non-Catholics who, accepting the restrained use of contraceptives, sought only to limit their availability. Catholic influence reinforced the efforts of other conservative interests but was not strong enough to secure legislation reflecting distinctively Catholic principles. 相似文献
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Producer Services, Economic Geography, and Services Tradability 总被引:3,自引:0,他引:3
We investigate how the incorporation of producer services linkages affects the outcome of an economic geography model. We specify the production of manufactures such that a variety of producer services is needed to transform tradable unfinished goods into final consumption goods. We find that service linkages promote the concentration of economic activity in a single region, but whether full concentration is achieved depends on the costs and mode of services trade. Applying the model to a multiregion world shows that incorporating producer services may also give rise to regions that specialize in different economic activities. 相似文献
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A. E. Van der Merwe G. J. R. Maat M. Steyn 《International Journal of Osteoarchaeology》2010,20(2):227-239
Examination of the histological structure of bone not only helps investigators to estimate age at death but can also aid in the diagnosis of palaeopathological lesions. The purpose of this paper is to assess whether histological features as described in the literature can confirm the macroscopic diagnoses of ossified subperiosteal haematomas associated with healed scurvy and syphilitic bone changes observed on the anterior tibiae of individuals from a 19th century mining community from Kimberley South Africa. The frequent occurrence of these two diseases amongst the deceased was well established in related hospital documents and governmental documents. A section of bone was removed from lesions on the tibiae of 14 individuals. These bone changes were macroscopically diagnosed as being indicative of either treponematosis ossified subperiosteal haematomas or non‐specific periostitis. Cross‐sections were prepared for microscopic investigation using a manual ground section technique. Ossified haematomas were histologically identified in seven individuals. These sections were characterised by normal cortical bone an intact original periosteal surface and newly formed radiating trabecular bone apposing it. Three phases of ossified subperiosteal haematoma formation and remodelling could be distinguished. Infectious bone changes most likely associated with treponematosis were observed in one individual. These were characterised by lysis and numerous resorption holes/channels. No clear distinction could be made between the internal spongy cortical or newly formed bone. Histological features described by some authors as characteristic of this condition could not be identified. In addition three individuals presented with microscopic features indicative of both the aforementioned bone affections and three did not show any pathological changes on microscopic level. It was concluded that although specific pathological conditions can most likely not be diagnosed purely on the basis of histomorphological observations broad distinctions could be made between lesions caused by the ossification of subperiosteal haematomas and bone changes due to infectious diseases. Copyright © 2009 John Wiley & Sons Ltd. 相似文献
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Martin van Gelderen 《History of European Ideas》2011,37(2):154-159
Through a discussion of Hugo Grotius’ conception of just war, this essay shows that within his critique of liberalism, Schmitt clashed with the very intellectual tradition he claimed to represent. Both historically and philosophically Schmitt's concept of the Ius Publicum Europaeum was a mirage. Indeed, his concept of the political was a rejection of the moral and civil philosophy that sees politics as the world of active citizens and commonwealths arguing with each other about fundamental questions of justice and equity. 相似文献
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