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The ‘Triple R’ approach on the restoration of dry stone walls, using recognizable, reversible and respectful constructive techniques is here illustrated. A set of restoration procedures are explained and applied to a UNESCO World Heritage site in Al-Baleed (Salalah, Sultanate of Oman) in the ‘Land of Frankincense’. The procedures were adapted in an innovative way to take into account the climate features of the Indian Ocean area (specifically, the effects of the monsoon season). All the restoration procedures aimed at conserving the site’s original architectural features by using only suitable stones and materials found on-site. Specific procedures have been adopted to consolidate walls, gates, foundations and sloping surfaces. Simple on-site mechanical tests and evaluation methods have been developed for a quick assessment of the safety level of the restored walls to ease future archaeological excavations. The application is related to a waterfront side of the ancient city built around the ninth century and added to over the next five centuries. These restoration procedures allowed for further archaeological excavations with new findings is here described.  相似文献   
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We examine the influence of various political actors on the substance and timing of presidential orders. Specifically, we analyze President John F. Kennedy’s decision to issue E. O. 11063, which directed the federal bureaucracy to eliminate discrimination in the sale or lease of residential property overseen by the federal government. We show that this order did not result solely from Kennedy’s policy preferences; rather, it was a product of persuasion by several political actors who coaxed Kennedy to act. This reinforces previous findings that the president’s power of the pen is often conditioned by the informal political costs of unilateral executive action.  相似文献   
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Experimental studies reveal complex dissolution behavior of quartz in aqueous NaCl solutions at high temperature and pressure, involving variation from salting‐in to salting‐out that changes with temperature, pressure, and salt concentration. The behavior is not explainable by traditional electrostatic theory. An alternative hypothesis appeals to complexing of SiO2 with NaCl and can explain the observations. However, the hypothesis of complexing, as previously applied, is inadequate in several respects: it neglects polymerization of solute silica, regards the SiO2‐NaCl hybrid complex(es) as anhydrous, which seems unlikely, and invokes an incorrect stoichiometry of the hydrated silica monomer, now known to be Si(OH)4?2H2O. These neglected features can be incorporated into the complexing model in a revised formulation based on a simple thermodynamic analysis using existing quartz solubility data. The analysis leads to a quasi‐ideal solution model with silica monomers, dimers, and two distinct hydrous SiO2‐NaCl hybrid complexes with overall NaCl:H2O = 1:6, one Na‐bearing and one Cl‐bearing. Their (equal) molar concentrations (Xhc) are governed by a pressure‐ and temperature‐dependent equilibrium constant, , where aNacl and are the respective activities of the solvent components. The stability of the hybrid complexes (i.e., their concentration) is very sensitive to H2O activity. The entire set of experimental quartz‐solubility data at 700°C, 1–15 kbar, is reproduced with high fidelity by the expression (P is pressure in kbar), including the transition from low‐pressure salting‐in to high pressure salting‐out. The results indicate that hybrid SiO2‐NaCl complexes are the main hosts for dissolved silica at NaCl concentrations greater than 6 wt%, which are likely common in crustal fluids. At higher temperatures, approaching the critical end point in the system SiO2‐H2O, the model becomes progressively inaccurate, probably because polymers higher than the dimer become significant as SiO2 concentration increases.  相似文献   
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The Early to Middle Bronze Age transition in Northern Mesopotamia has received great attention for the apparent concurrence of aridification, deurbanisation, and the end of the Akkadian empire around 2200 BCE. Our understanding of the “crisis” has been almost exclusively shaped by ceramics, demography, and subsistence. Exchange and the associated social networks have been largely neglected. Here we report our sourcing results for 97 obsidian artefacts from Urkesh, a large urban settlement inhabited throughout the crisis. Before the crisis, six obsidian sources located in Eastern Anatolia are represented among the artefacts. Such a diversity of Eastern Anatolian obsidians at one site is hitherto unknown in Mesopotamia. It implies Urkesh was a cosmopolitan city with diverse visitors or visitors with diverse itineraries. During this crisis, however, obsidians came from only two of the closest sources. Two to three centuries passed before varied obsidians reappeared. Even when an obsidian source reappears, the raw material seems to have come from a different collection spot. We discuss the likely exchange mechanisms and related social networks responsible for the arrival of obsidians at Urkesh and how they might have changed in response to climatic perturbations and regional government collapse.  相似文献   
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Previous studies have endeavored to use petrophysical traits of obsidian, particularly its magnetic properties, as an alternative to conventional geochemical sourcing, one of the greatest successes in archaeological science. Magnetic approaches, however, have not seen widespread application due to their mixed successes. In a time when geochemical analyses can be conducted non-destructively, in the field, and in a minute or two, magnetic measurements of obsidian must offer novel archaeological insights to be worthwhile, not merely act as a less successful version of geochemistry. To this end, we report the findings of our large-scale study of obsidian magnetism, which includes 734 geological obsidian specimens and 97 artifacts measured for six simple magnetic parameters. Based on our results, we propose, rather than using magnetic properties to source artifacts to a particular obsidian flow (inter-flow sourcing), these properties are best used to differentiate quarrying sites within an individual flow (intra-flow sourcing). Our results also demonstrate that certain magnetic properties are highly affected by ancient knappers' material selection criteria. Furthermore, depending on the spatial scales of variation, which likely vary from flow to flow, we envision several potential applications of this approach, including integration into minimum analytical nodule analysis (MANA). Magnetic data appear to shift the scale of obsidian sourcing from flows to quarries and, in turn, enable new insights into raw-material procurement strategies, group mobility, lithic technology, and the organization of space and production.  相似文献   
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Abstract

In this article, the authors review Joseph Cropsey's last collection of essays, Humanity's Intensive Introspection. They argue that Cropsey's essays draw on resources in the Western tradition, both from within liberal thought and from ancient sources, to elevate human life and to fortify modern society, especially against contemporary critiques of liberalism. Philosophy's discovery of the inscrutability of the whole opens it to revelation and also provides a basis for philosophy's active contribution to an open or liberal society.  相似文献   
39.
Intentional dental modification, in the form of ablation and filing, is reported for the first time from Cambodia in two late prehistoric sites (Phum Snay and Phum Sophy, c. 2500 to 1500 bp ). Bioarchaeological research is relatively new for this region, and this study significantly adds to our reconstruction of past behaviours in mainland Southeast Asia. The skeletal samples combine both excavated material and large looted collections in the form of ossuaries. People from Phum Sophy and Phum Snay had similar rates of anterior maxillary dental ablation, 60 and 47%, respectively, and 21.4 and 7.7%, respectively, in the mandible. Patterns of ablation most commonly involve the removal of the maxillary lateral incisors. Intentional filing was less common than ablation but affected Phum Snay and Phum Sophy individuals to a similar level (4–7%). Filing was also restricted to the anterior dentition, and a range of patterns were evident, many involving filing of the mesial and distal aspects of the crown of the upper and lower incisors and canines to give a pointed appearance. Patterns of ablation or filing were not strongly associated with a particular sex or age group. However, a limited number of ablation and filing patterns were exclusive to each site. The significance of this practice in relation to rites of passage, status, community and family relationships, and trauma is discussed. It is also shown that the modifications show distinct differences in prevalence and pattern, particularly that of filing, to nearby temporal neighbours in southern Cambodia and northeast Thailand, suggesting a unique cultural behaviour for this region. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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