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81.
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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This article evaluates the effects of external financial liberalization on Brazilian macroeconomic performance from 1995 to 2016. Its main contributions are to assess the influence of the global financial cycle on the level of external financial liberalization and to analyse the short- and long-run macroeconomic effects of such liberalization on the performance of a peripheral economy in the global currency hierarchy. Methodologically, the article employs the Markov-Switching Vector Autoregressive and Vector Error Correction models. The results show that the global financial cycle directly affects cross-border financial flows and frames the impact of external financial liberalization on the macroeconomic performance. The article concludes that external financial liberalization has negative macroeconomic effects in the short run and generates a trade-off between stability and growth in the long run.  相似文献   
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The implementation of a 3D Electrical Resistivity Tomography (ERT-3D) survey was carried out in El Pahñú archaeological site, Hidalgo State, Central Mexico. A combination of a new ERT arrays allowed studying the subsoil beneath the Main Pyramid built near the edge of a plateau, along with another important structure (the Tecpan), which was a smaller structure that lodged the governmental council in pre-Hispanic times. The recorded information was acquired through the combination of several electrodic designs: L-Corner (LC), Equatorial (Eq), and Minimum Coupling (MC). For the Main Pyramid, the electrodes were set up around the perimeter of the structure, since they were not permitted to be inserted over the edifice, thus preventing damages to the architectonic elements. The second structure allowed inserting electrodes on selected spots within the architectonic space. The combination of the different arrays made possible the acquisition of 1204 apparent resistivities beneath the Main Pyramid and 2460 resistivity data beneath the Tecpan. The apparent resistivity data were inverted to obtain a three dimensional display of the subsoil electrical resistivity beneath the archaeological structure. The interpreted resistivity model under the Main Pyramid displayed a highly resistive structure towards its northern face that could be associated with infill. Such material was employed by the ancient constructors to level the terrain close to the edge of the cliff. Another interesting anomaly was found towards the central portion of the structure that could be associated to a foundation offer. The interpretation of data beneath the Tecpan identified the structural foundations and other interesting anomalies related to the different occupational times. The investigation supported the archaeological investigation of the site, suggesting areas of potential geological risk and of archaeological interest. For example, the Main Pyramid presents serious stability problems, indicating that the infill has weakened, producing cracks threatening long-term pyramid integrity.  相似文献   
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The phenomenon of equifinality complicates behavioral interpretations of faunal assemblages from contexts in which Pleistocene hominins are suspected bone accumulators. Stone tool butchery marks on ungulate fossils are diagnostic of hominin activities, but debate continues over the higher-order implications of butchered bones for the foraging capabilities of hominins. Additionally, tooth marks imparted on bones by hominins overlap in morphology and dimensions with those created by some non-hominin carnivores, further confounding our view of early hominins as meat-eating hunters, scavengers or both. We report on the manual/oral peeling of cortical layers of ungulate ribs as taphonomically diagnostic of hominoid/hominin meat- and bone-eating behavior that indicates access to large herbivore carcasses by hominins at the site of BK, Olduvai. Supporting these inferences, we show that certain types of rib peeling damage are very rare or completely unknown in faunas created by modern carnivores and African porcupines, but common in faunas modified by the butchery and/or consumption activities of modern humans and chimpanzees, during which these hominoids often grasp ribs with their hands, and then used their teeth to peel strips of cortex from raggedly chewed ends of the ribs. Carnivores consume ungulate ribcage tissues soon after kills, so diagnostic traces of hominin butchery/consumption on ribs (i.e., peeling and butchery marks) indicate early access to ungulate carcasses by BK hominins. Tooth marks associated with the peeling and butchery marks are probably hominin-derived, and may indicate that it was not uncommon for our ancestors to use their teeth to strip meat from and to consume portions of ribs. Recognition of rib peeling as a diagnostic signature of hominoid/hominin behavior may also aid the search for pre-archaeological traces of hominin meat-eating.  相似文献   
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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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