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21.
In a first region wide study, starch grains from human dental calculus from the pre-Columbian insular Caribbean (dating to ca. 350 B.C.–A.D. 1600) are used to identify important plant foods in the diet and to assess potential dietary differences related to age or sex. Results give important insights into pre-Columbian maize (Zea mays) consumption throughout the region, confirming recent studies that indicate that maize was more commonly consumed in the insular Caribbean than originally thought. No age or sex based differences in maize consumption were found. Furthermore, based on the results of new experiments regarding grinding and pressure damage to starch grains, it is clear that maize in the Caribbean was ground, baked and consumed as bread as was the case in large parts of the mainland. Based on our results we tentatively suggest maize consumption in the Caribbean was at least in some cases associated with feasting and ceremonial activities. The variety in other plant foods identified (mostly tuberous root crops) shows that the pre-Columbian inhabitants of the region consumed a broad spectrum, but locally variable diet in which a variety of root crops functioned as staple crops, including marunguey (Zamia sp.) and sweet potato (Ipomoea batatas). We found no indications for the traditionally assumed heavy reliance on manioc (Manihot esculenta) cultivation in the region.  相似文献   
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Long-term social and natural processes reciprocally interact in spatially and temporally dynamic socioecosystems. We describe an integrated program of patch-based survey and subsurface testing aimed at studying long-term socioecology, focusing especially on the transition from foraging to farming in Mediterranean Spain. Measures of landuse ubiquity, intensity, dispersion, and persistence trace late-Pleistocene through mid-Holocene socioecological trajectories in four upland valleys. Although farming replaced foraging in all four valleys, the timing and nature of this transition varied because of cumulative interactions between social and natural processes. These processes continue to structure modern landscapes and landuse in these valleys.  相似文献   
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The architectural remains at Pasargadae were built of three different stones classified according to their colors (beige, dark-gray, and green-gray). The stones show different macroscopic features, such as texture and decay patterns. The aim of this study is to identify the composition of the stones and to evaluate the main decay factors through petrographic studies in order to make conservation decisions more compatible. Petrochemical analyses show that the stones are in fact limestones with different features; two of them have a compact texture (beige and dark-gray stones), while the third has a fairly porous structure (green-gray stone). In some beige stone samples, dolomite was identified. Despite the fact that the presence of salt is a possible decay factor, X-ray diffraction analysis did not report any salt. According to SEM observations, the main reasons for decay in dark-gray and green-gray stones are the dissolution of calcite crystals and the swelling of clay minerals. The main decay factor in the beige stone, by contrast, is dissolution induced by microorganism activity. However, a patina formed by lichens on the surface of the beige stone, although aesthetically detrimental, protects it against further decay.  相似文献   
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Abstract

We offer a new methodology for the construction of annual population stocks over the very long run. Our method does not require the assumption of a closed economy, and can be used in situations in which local annual gross flows are obtainable. Combining gross flows with intermittent census-type data, it is possible to arrive at local, regional and national population stock estimates at annual frequencies. We provide an application to early modern and nineteenth century Portugal, using a large sample of parish-level statistics up to the first modern census of 1864. All six major regions of the country are considered.  相似文献   
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Free-standing rigid objects and structures are dominantly found to exhibit rocking behavior and can be vulnerable to overturning during an earthquake as demonstrated by numerous past earthquake events. Such objects are typically considered to be displacement sensitive with their rocking response being well presented by the Peak Displacement Demand (PDD) parameter of the supporting floor’s motion. This in turn can be directly related to an object’s width (along the direction of motion) for assessing its vulnerability to overturn. Such findings have been sufficiently justified by refined dynamic analysis supported by experimental evaluations which were based on rigid blocks with uniform geometric format (i.e., regular in their mass distribution). However, vulnerable rocking objects can be asymmetric and accordingly their sensitivity to floor displacement cannot be directly related to their width. The key parameter which defines irregular objects’ response to rocking motion is represented by the degree of eccentricity of their center of mass. In this study, the well-known rocking equation of motion is reconfigured and devised to model the rocking responses for 280 irregular objects undergoing eight earthquake motions which included artificial and recorded earthquakes. Analytical results obtained from solving the adjusted equation of motion were evaluated with sophisticated finite element (FE) models simulating the 280 irregular cases. This experimentally validated FE modeling approach was found to be time- and cost-effective for understating the rocking behavior of asymmetric objects as well as clarifying an interesting relationship between the object’s damping level and the condition of the supporting base (i.e., whether being provided with supports at the points of rotation or not). The rocking response of irregular objects was found to be highly influenced by the level of eccentricity of the object when excited by motions with high displacement amplitudes, while such influence was not found noticeable by wider objects. Based on the developed trends between the maximum top displacement of irregular objects and the PDD, an expression for estimating the rocking amplitudes is proposed which is a function of the object’s eccentricity.  相似文献   
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The use of red pigments linked to burial practices is widely documented in the Iberian prehistoric record and very often it has been traditionally interpreted as a ritual practice entailing the utilisation of local raw materials (iron oxides). Some research works, nevertheless, have also detected the use of red pigments which can only be interpreted as allochthonous. The red pigments spread over a single inhumation in a monumental Megalithic tomb surrounding Valencina de la Concepción Copper Age settlement was studied by means of X-ray diffraction, field emission scanning electron microscopy with energy dispersive X-ray spectroscopy, X-ray microfluorescence, micro-Raman and Fourier transform infrared spectroscopies. This approach allowed characterising the red pigments as cinnabar, mixed with tiny amounts of iron oxides. The presence of cinnabar, a product that was necessarily imported, in a context of an exceptional set of grave goods, suggests that the use of cinnabar was linked not only to ritual but also to practices related to the display of social status.  相似文献   
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On the basis of stable carbon and nitrogen isotope analysis of human remains, this paper provides evidence for the retention of hunter–gatherer economies among coastal inhabitants in northern Chile during the late Holocene – at the same time that inland populations were adopting agricultural economies. Coastal diets from the Caleta Vitor region of the Atacama Desert were dominated by marine-based foods, predominantly from upper trophic levels. The focus on reliable marine food resources is interpreted as a risk minimisation strategy in this marginal arid environment. Although these coastal hunter–gatherers adopted other goods and traditions from agricultural populations, their participation in this larger interregional exchange network did not affect their basic subsistence economies.  相似文献   
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