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41.
In the island of Jaina, Campeche, red and yellow pigmented bones have been found. The study of the yellow and red colors in these burials is important for their possible interpretation, either religious, intentional coloring, or to understand taphonomic processes such as reactions of the original pigments with other compounds. Yellow color on bones is unusual in prehispanic burials.  相似文献   
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Recent excavations at the Postclassic (AD 1050–1440) Maya site of Mayapán, Mexico, have uncovered a variety of metal objects, metal production debris, and ceramic objects that appear to be linked to metallurgical activities at the site. Our present study investigates a corpus of small ceramic objects to determine if these objects was used in metallurgical processes such as lost-wax casting. A variety of analytical techniques was utilized, including x-ray fluorescence, electron probe, petrography, and reflected light microscopy. Metal residues were detected on the surfaces of several objects, and copper prills were identified within the ceramic fabric, suggesting that the ceramics were exposed to liquid metal during remelting and/or casting events. A comparison of the microstructures of these metallurgical ceramics to typical ceramics from Mayapán demonstrates that the fabrics are very different, and suggests that the metallurgical ceramics were specifically engineered to function in the high temperature environment required for metallurgy. The distribution of metal and metallurgical ceramics across the site of Mayapán suggests that metal production activities may have been more widely distributed and practiced than earlier thought.  相似文献   
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ABSTRACT We decompose the recent changes in regional inequality in Brazil into its components, highlighting the role of spatially blind social programs. We aggregate personal income micro data to the state level, differentiating nine income sources, and assess the role of these components in the observed changes in regional inequality indicators. The main results indicate that the largest part of the recent reduction in regional inequality is related to the dynamics of the market‐related labor income, with manufacturing and services favoring deconcentration. Labor income in agriculture, retirement and pensions, and property rents and other sources favored concentration. The social programs Bolsa Família and Benefícios de Prestação Continuada are responsible for more than 24 percent of the reduction in inequality, although they account for less than 1.7 percent of the disposable household income. Such positive impact on regional concentration is impressive, since the goals of the programs are clearly nonspatial.  相似文献   
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In the summer of 1561, a strong seismic sequence struck southern Italy, then the Spanish-ruled Kingdom of Naples. Both the Italian seismological tradition and the latest catalogues locate it in the Vallo di Diano (Diano Valley), a low-seismicity intermontane basin 100 km south-east of Naples. We explore the hypothesis that current perception of the 1561 earthquake is distorted by the nature of the historical dataset from which its parameters have been assessed, and which mostly derive from a single—albeit very detailed—primary source. We present and discuss several previously unconsidered original accounts. Our results cast doubts on the traditional interpretation of the earthquake, which could have been either one Vallo di Diano mainshock or several strong earthquakes within a time/space window compact enough for contemporary viewers to perceive them as one. Unquestionably, there is much more to the 1561 earthquake(s) than previously appeared. We hope that this groundbreaking effort will rekindle the interest of the seismological community in this seismic episode, our knowledge of which is still far from complete.  相似文献   
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The 2001 UNESCO convention for the Protection of Underwater Cultural Heritage (UCH) encourages and supports projects that would make accessible to the general public underwater cultural sites. Since 2010 the Catalonian Federation of the World Underwater Federation (FECDAS), have been developing outreach activities with the objective of promoting the protection of the UCH among recreational scuba divers. The purpose of this paper is to introduce one such project, the Punta Santa Anna in Blanes, Spain. This project has three objectives: the promotion of UCH to the general public, the in situ protection of this underwater archaeological site, and a case study on iron corrosion processes. FECDAS/CMAS will create an underwater archaeological park where recreational scuba divers will be able to visit some purposely selected archaeological iron cannons. To expose UCH to the general public will potentially affect the integrity of these artefacts. This risks potential damage and so, with the objective of minimizing potential threats, a series of protective measures and a systematic monitoring programme have been planned. The programme is designed to study the relationship between the underwater environment and the artefacts. The aim is to acquire a better understanding of the corrosion processes of iron objects present in marine underwater sites.  相似文献   
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The palynoflora of surface samples of glacial deposits from the Guandacol Formation in the Cerro Bola area of the Argentinian Paganzo Basin is documented. The existence of glacial related diamictites in this area has been previously ignored. The fossiliferous levels are located in section B of the formation, which corresponds to the earlier stages of deglaciation. The assemblage contains abundant monosaccate pollen grains whose global incoming is not older than early Namurian (Middle Carboniferous). Many species of this palynoflora are present in equivalent stratigraphic sequences of Argentina and can be referred to Sub-biozone A of the Raistrickia densa-Convolutispora muriornata Biozone (Namurian-Stephanian). New species described here are Cyclogranisporites rinconadensis and Tricidarisporites gutii.  相似文献   
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