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951.
In this work, we present the results of the characterization of 20 lime plaster samples taken from the Sacred Precinct of Tenochtitlan (Mexico City), the ancient capital of the Aztec empire. The samples come from different buildings of this precinct (A, B and D) and from the west façade of phase VI of the Templo Mayor pyramid. The objective of the work is to characterize the plaster samples, to understand the raw materials used, and to evaluate the presence of similarities and differences among the samples in the building techniques and raw materials employed. All the samples were studied with OM, SEM–EDS and LA–ICP–MS. The study provided evidence of the plastering and replastering practice in the same constructive phases. The results of the analyses showed the existence of important similarities and differences among buildings and constructive phases in the Sacred Precinct. In order to understand the provenance of the limestone used in the plasters, the lumps and the binder of the samples were analysed. The results were compared with those of the limestone outcrops located in central Mexico. The provenance study showed that all the limestone used in the construction of the analysed buildings of Tenochtitlan's Sacred Precinct comes from the Tula region.  相似文献   
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Twenty‐first‐century political crises stretching from Europe to the Middle East and the Asia–Pacific have undermined the worldview that governed post‐Cold War western thinking about a liberal end of history. This worldview assumed that shared norms and transnational institutions would transform the state based‐order. In this context, the use of force is considered appropriate only for humanitarian ends meeting a set of predetermined axioms laid down in chapter 7 of the UN Charter. Yet for any strategy to be effective—in an international order subject to change—a clear political aim is required, which might deviate from the general rule. Preoccupied with universal postulates, legal normativism has lost sight of the particular. The argument put forth in this article is that the failure of contemporary western foreign policy in the twenty‐first century to address this limitation or to prioritize political ends has led to strategic confusion from Afghanistan to Syria and Ukraine. In this context, it might be useful to reappraise the utility of abstract rationalist approaches to global governance and return instead to an earlier understanding of statecraft that avoided premature generalizations and treated norms as maxims of prudence rather than axioms requiring universal application.  相似文献   
959.
This paper explores the sorting process in response to differing levels of aviation noise exposure in a housing market. Spatiotemporal hedonic pricing (HP) and stated choice (SC) results reflect nonlinearities and stigma. The HP models reveal nonlinear noise depreciation increasing from 0.40 to 2.38 percent per decibel as noise increases, while the SC noise values are lower in an area with high long‐term noise exposure. These nonlinearities are attributed to the spatial sorting of noise tolerant individuals. HP results from the same “noisy” area show a “stigma” from noise during the first year after the complete removal of aviation noise.  相似文献   
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This paper evaluates the impact of accessibility on the productivity of Spanish manufacturing firms. We suggest the use of accessibility indicators of workers and commodities, integrating transport, land use, and individual components, computing real distances or traveling times using the Spanish full road network. Estimated firms’ total factor productivity is explained as a function of the accessibility indicators and additional control variables. Results evidence the crucial role on firms’ productivity to the accessibility of commodities and to a slightly lesser extent the workers.  相似文献   
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