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101.
Since 2005 we have been utilizing accelerator mass spectrometry (AMS) 14C dating in research on calcium oxalate crusts associated with open air rock art of the Iberian Peninsula. In this paper we present two dates linked with three eye-idol pictographs at Abrigo de los Oculados (Henarejos, Cuenca, Spain). Radiocarbon ages for these motifs agree with the expected iconography-based archaeological chronology. Such oxalate dates could provide an independent basis for evaluating chronological theories for post-Palaeolithic sites, designated in the UNESCO World Heritage List as Rock Art of the Mediterranean Basin on the Iberian Peninsula.  相似文献   
102.
During the Middle Horizon (AD 650–1000), the Wari polity expanded its sphere of control in various regions of the Andes, including Nasca on the south coast of Peru. The nature of the interaction between Wari and local communities varied. This study explores the consequences of Wari contact in the Nasca region at the site of La Tiza, which includes individuals dated to the Early Intermediate, Middle Horizon, and Late Intermediate periods. Using evidence for burial ritual along with demographic, paleopathological and isotopic data, population composition, mobility, diet, and health are investigated. δ13C data indicate a relatively stable diet through time at La Tiza with evidence for continued maize consumption, and paleopathological results indicate health problems associated with this type of diet. δ18O and 87Sr/86Sr data suggest that most of the individuals buried at La Tiza were local to the area. However, two female adults from the Middle Horizon burials are characterized as nonlocal based on δ18O and 87Sr/86Sr values and several individuals overlap with the 87Sr/86Sr local range for the Wari heartland. In conjunction with the use of new tomb types during this period these results highlight the ideological and populational changes occurring with Wari contact at La Tiza.  相似文献   
103.
Abstract: The complexity of water management requires an explanatory framework that is able to capture the multidimensionality of the relations between nature and society increasingly mediated by the state. The evolution of water problems in the Baixada Fluminense, a wetland area situated to the north of Rio de Janeiro, provides a paradigmatic example of how water management becomes incorporated into the fluid politics between state, nature and society. The local experience is examined by making use of the strategic‐relational approach (after Bob Jessop) expanded to urban political ecology. The concept of “trialectics” is proposed as an ontological representation of the interconnections between the state apparatus, class‐based relations and the socionatural elements of the water cycle. The empirical results show that, in a situation of precarious water supply, regular flooding and severe river degradation, state interventions have tended to favour certain groups and areas, which only intensifies the politicisation of water management.  相似文献   
104.
The present paper reports the chemical data obtained on samples of pigmenting materials contained in 31 miniature vessels found in a burial found in Teopancazco, a multiethnic neighborhood center located in the southeastern sector of the archaeological site of Teotihuacan (Central Mexico) and the analytical protocol established for the complete characterization of these archaeological materials. For this purpose a multi-technique approach based on the combination of several non destructive and micro-destructive instrumental techniques, namely, light microscopy (LM), scanning electron microscopy-X-ray microanalysis (SEM-EDX), transmission electron microscopy (TEM), voltammetry of microparticles (VMP), X-ray microdiffraction (μXRD), X-ray diffraction (XRD), UV-Vis spectrophotometry, FTIR spectroscopy and gas chromatography-mass spectrometry (GC-MS) has been developed in an attempt to completely characterize these materials. These instrumental techniques provide reliable and complementary data including elemental and mineralogical composition, identification of functional groups as well as speciation studies of electroactive species. Among the most relevant findings, volcanic pyroclastic rocks and clayey soils, most probably, from the Teotihuacan valley as well as galena, jarosite and mica from other provenances in Mesoamerica, have been identified. Charcoal and Ocote resin have also been identified. The chemical composition of the samples is discussed with a view to the possible function as cosmetic materials and their use in funerary rites. The results have been critically compared with those others obtained in other ancient civilizations. The study carried out on the materials found in the burial 105 is especially relevant insofar it represents the first evidence, scientifically characterized, of the use of cosmetics in Mesoamerica at this early period (AD 200-550).  相似文献   
105.
106.
In this report we present and discuss an unpublished letter written by Santiago Ramón y Cajal in October 1904 in relation to his possible nomination for the Nobel Prize for Physiology and Medicine. This letter shows that Cajal was aware of his previous nominations for the Prize. He was convinced that these nominations had not been successful because neither anatomy nor histology were among the sciences included in the Nobel Statutes' definition of Physiology or Medicine. He gives a list of the merits he thought might be used for a new nomination, which included only works concluded during the previous five years.  相似文献   
107.
108.
Central areas enjoy greater efficiency in the production of goods and services than do outlying areas. Because of the inherent advantages of central areas over outlying areas, disparities among regions do not vanish over time. On the contrary, centripetal forces increase inequalities across space. The phenomena of increased globalization, trade liberalization and treaties among countries not only enable the flow of labour, products (export) and foreign direct investment but also help reduce spatial inequality between countries. These phenomena also induce greater spatial economic concentration within a country. Thus, although disparities among countries decrease, a widening gap is observed between regions within countries and within large urban areas. In the empirical part, we analyse the general patterns of spatial inequality found among 55 localities in Israel with population size over 20,000. Looking at the spatial inequality relationship, both within and between cities in Israel, we show how all economic indicators measured, including inequality, decrease with distance from the core. Localities in the periphery that experience greater equality also experience lower average income, lower education, less self-employment and more unemployment.  相似文献   
109.
The experimental and numerical results obtained by Research Units of the University of Basilicata and University of Calabria for a steel frame, bare or equipped with metallic yielding hysteretic dampers (HYDs), are compared. The shaking table tests were performed at the Structural Laboratory of the University of Basilicata within a wide research program, named JETPACS (“Joint Experimental Testing on Passive and semiActive Control Systems”), which involved many Research Units working for the Research Line 7 of the ReLUIS (Italian Network of University Laboratories of Earthquake Engineering) 2005–2008 project. The project was entirely founded by the Italian Department of Civil Protection. The test structure is a 1/1.5 scaled two-story, single-bay, three-dimensional steel frame. Four HYDs, two for each story, are inserted at the top of chevron braces installed within the bays of two parallel plane frames along the test direction. The HYDs, constituted of a low-carbon U-shaped steel plate, were designed with the performance objective of limiting the inter-story drifts so that the frame yielding is prevented. Two design solutions are considered, assuming the same stiffness of the chevron braces with HYDs, but different values of both ductility demand and yield strength of the HYDs. Seven recorded accelerograms matching on average the response spectrum of Eurocode 8 for a high-risk seismic region and a medium subsoil class are considered as seismic input. The experimental results are compared with the numerical ones obtained considering an elastic-linear law for the chevron braces (in tension and compression), providing that the buckling be prevented, and the Bouc-Wen model to simulate the response of HYDs.  相似文献   
110.
In this paper, we given an economic interpretation of Kuhn's dual of the Steiner-Weber problem. It depends essentially on the notion that different transportation systems arerelevant for the primal and the dual. Moreover, the Euclidean metric underlies the interpretation of the primal, the block one that of the dual.  相似文献   
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