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71.
72.
In the Amazon Basin, within a landscape of infertile soils, fertile Anthrosols of pre-Columbian origin occur (Amazonian Dark Earths or terra preta de Índio). These soils are characterized by high amounts of charred organic matter (black carbon, biochar) and high nutrient stocks. Frequently, they were considered as sign for intensive landscape domestication by way of sedentary agriculture and as sign for large settlements in pre-Columbian Amazonia. Beyond the archaeological interest in Amazonian Dark Earths, they increasingly receive attention because it is assumed that they could serve as a model for sustainable agriculture in the humid tropics (terra preta nova). Both questions lack information about the pre-Columbian practices which were responsible for the genesis of Amazonian Dark Earths. It has often been hypothesized that deposition of faeces could have contributed to the high nutrient stocks in these soils, but no study has focussed on this question yet. We analyzed the biomarkers for faeces 5β-stanols as well as their precursors and their 5α-isomers in Amazonian Dark Earths and reference soils to investigate the input of faeces into Amazonian Dark Earths. Using Amazonian Dark Earths as example, we discuss the application of threshold values for specific stanols to evaluate faeces deposition in archaeological soils and demonstrate an alternative approach which is based on a comparison of the concentration patterns of 5β-stanols with the concentration patterns of their precursors and their 5α-isomers as well as with local backgrounds. The concentration patterns of sterols show that faeces were deposited on Amazonian Dark Earths.  相似文献   
73.
In the Iberian Peninsula, leporids, and specifically rabbits, play a key role in the understanding of hunter-gatherer economies. They appear to have been especially important in the Tardiglacial, when large numbers of small prey animals and of the European rabbit (Oryctolagus cuniculus) in particular, are a ubiquitous feature of faunal assemblages from archaeological sites. Since a large number of non-human predators can also contribute to the formation of such assemblages, the ability to discriminate between bones accumulated by humans and by other kinds of predators is a key prerequisite to their interpretation. On the basis of systematic actualistic studies carried out on modern leporid remains produced by mammalian terrestrial carnivores, nocturnal and diurnal raptors, and humans, we identified diagnostic taphonomic indicators of the different predators. In this paper, the patterns observed on the modern material are applied to the taphonomical analysis of two archaeological samples of rabbit and hare remains from Mousterian and Solutrean layers of Gruta do Caldeirão, a cave site located in Central Portugal. Our results suggest that Eagle Owl (Bubo bubo) were mainly responsible for the Mousterian accumulations, whilst the Solutrean ones were most likely the result of human activity. These data support the notion that, in Iberia, significant reliance on rabbits does not become a feature of subsistence strategies until later Upper Palaeolithic times.  相似文献   
74.
The earliest known personal ornaments come from the Middle Stone Age of southern Africa, c. 75,000 years ago, and are associated with anatomically modern humans. In Europe, such items are not recorded until after 45,000 radiocarbon years ago, in Neandertal-associated contexts that significantly predate the earliest evidence, archaeological or paleontological, for the immigration of modern humans; thus, they represent either independent invention or acquisition of the concept by long-distance diffusion, implying in both cases comparable levels of cognitive capability and performance. The emergence of figurative art postdates c. 32,000 radiocarbon years ago, several millennia after the time of Neandertal/modern human contact. These temporal patterns suggest that the emergence of “behavioral modernity” was triggered by demographic and social processes and is not a species-specific phenomenon; a corollary of these conclusions is that the corresponding genetic and cognitive basis must have been present in the genus Homo before the evolutionary split between the Neandertal and modern human lineages.  相似文献   
75.
ABSTRACT

Based on research conducted as part of the Sydney Playground Project, this paper provides an exploratory investigation of the perspectives of girls relating to the ideal school playground experience, and whether their perspectives are influenced by a loose-parts playground intervention. The focus is on the play behaviours of 22 girls aged 8–10 years, from the perspective that school playgrounds are generally designed in ways that are more suited to the play behaviours of boys. The research is based on a qualitative analysis of children’s drawings, interviews and focus groups, exploring meanings associated with desired play experiences. Findings indicate that girls’ views of the ideal school playground are influenced by the geographies of the spaces they play in, and that girls highly valued changes provided by a loose-parts intervention.  相似文献   
76.
The Odyssey Case refers to the dispute between Odyssey Marine Exploration Inc. (OME) and the Kingdom of Spain in the US courts to determine the ownership of more than 500,000 coins, as well as other artefacts, that OME recovered from a wreck‐site it had code‐named Black Swan. However, the process was much more than a dispute over the coins. It reflected many of the components involved in the protection of underwater archaeological heritage, especially when economic and political interests are at stake. Written from the perspective of an archaeologist working for the regional authority responsible for developing archaeological policy, this paper tries to assess the case's impact on future policy development.  相似文献   
77.
After two turbulent years in which different pathways for the future of the political and institutional framework of Portugal clashed, the country began a process of consolidation of the democratic institutions delineated between 1975/6. However, the role played by the military in the fall of the previous dictatorial regime and the fragility of the new democratic institutions did not allow their immediate withdrawal from political life. The President of the Republic was a military man and the political parties had agreed to maintain an unelected sovereign body, the Council of the Revolution, which only dissolved in 1982. Based on primary sources that only recently became available, this article presents some elements that help to understand the success of democratic consolidation in Portugal. This long process should not be interpreted as a confrontation between civilians, desirous to put an end to military tutelage, and the military, who at all costs sought to keep their privileges. The dividing line should be placed between those who defended the maintenance of the status quo, and the supporters of military subordination to the civil power.  相似文献   
78.
The article examines Vidas secas (1938) by Brazilian writer Graciliano Ramos as bridging biopolitical reflections on animality and new materialist reflections on animal studies. By tracing the bond between canine and human in Vidas secas as a canine melancholia, from Lacanian extimité into Donna Haraway’s species companionship, I expose the implicit theory of animality of the novel as an interspecies politics of survival. In doing this, I present a new frame of interpretation for the novel that places its particular kind of melancholia as untimely contemporary.  相似文献   
79.
ABSTRACT

Although many experimental tests and numerical models are available in the literature, the numerical simulation of the seismic response of existing masonry buildings is still a challenging problem. While the nonlinear behavior of masonry structures is reasonably predictable when the out-of-plane behavior can be considered inhibited, when the in-plane and out-of-plane responses coexist and interact, simplified models seem unable to provide reliable numerical predictions. In this article, taking advantage of the experimental tests carried out in a shaking table on two masonry prototypes at LNEC, a macro-element approach is applied for the numerical simulations of their nonlinear response. The adopted approach allows simulating the nonlinear behavior of masonry structures considering the in-plane and out-of-plane responses. Since it is based on a simple mechanical scheme, explicitly oriented to representing the main failure mechanisms of masonry, its computational cost is greatly reduced with respect to rigorous solutions, namely nonlinear FEM approaches. Two modeling strategies are adopted, namely a regular mesh independent from the real texture of the prototypes and a detailed one coherent with the units disposal. The numerical results are discussed and the correlation between the nonlinear static analyses and the dynamic response is provided.  相似文献   
80.
ABSTRACT

Earthquakes cause severe damage to masonry structures due to inertial forces acting in the normal direction to the plane of the walls. The out-of-plane behavior of masonry walls is complex and depends on several parameters, such as material and geometric properties of walls, connections between structural elements, the characteristics of the input motions, among others. Different analytical methods and advanced numerical modeling are usually used for evaluating the out-of-plane behavior of masonry structures. Furthermore, different types of structural analysis can be adopted for this complex behavior, such as limit analysis, pushover, or nonlinear dynamic analysis.

Aiming to evaluate the capabilities of different approaches to similar problems, blind predictions were made using different approaches. For this purpose, two idealized structures were tested on a shaking table and several experts on masonry structures were invited to present blind predictions on the response of the structures, aiming at evaluating the available tools for the out-of-plane assessment of masonry structures. This article presents the results of the blind test predictions and the comparison with the experimental results, namely in terms of formed collapsed mechanisms and control outputs (PGA or maximum displacements), taking into account the selected tools to perform the analysis.  相似文献   
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