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991.
The objective of this analysis is mainly to construct an intuitive measure of the performance of the National Rural Employment Guarantee Scheme (NREGS) in India. The focus is on divergence between demand and supply at the district level. Some related issues addressed are: (i) whether the gap between demand and supply responds to poverty; and (ii) whether recent hikes in NREGS wages are inflationary. Our analysis confirms responsiveness of the positive gap between demand and supply to poverty. Also, apprehensions expressed about the inflationary potential of recent hikes in NREGS wages have been confirmed. More importantly, higher NREGS wages are likely to undermine self-selection of the poor in it.  相似文献   
992.
The management of carbon emissions holds some prospect for challenging sustainable development as the organising principle of socio-environmental regulation. This paper explores the rise of a distinctive low-carbon polity as an ideological state project, and examines its potential ramifications for the regulation of economy–environment relations at the urban and regional scale. Carbon control would seem to introduce a new set of values into state regulation and this might open up possibilities for challenging mainstream modes of urban and regional development in a manner not possible under sustainable development. But low-carbon restructuring also portends intensified uneven development, new forms of state control and a socially uneven reworking of state–society relations. In order to explore these issues we start by setting out a framework for conceptualising environmental regulation based around the idea of eco-state restructuring. This idea is introduced to capture the conflicts, power struggles and strategic selectivities involved as governments seek to reconcile environmental protection with multiple other pressures and demands. Overall the paper seeks to make a distinctive contribution to theoretical work on state environmental regulation and the emerging spatial dimensions of climate policy.  相似文献   
993.
Richards et al. (2000) reconstructed the diet of the human remains found in Gough's and Sun Hole Cave through isotope analysis. They concluded that these people consumed an entirely terrestrial-based diet. Their reconstruction was based upon comparison of the results from human bones with those from a very small number of associated animals. The diets of the Gough's and Sun Hole Cave human were different from the other six Upper Palaeolithic humans from the British Isles for which dietary information has been obtained through isotope analysis. The work of Richards et al. (2000) suggests that they were the only ones for whom marine or freshwater resources did not play a significant role in their diets. We test this through further analyses of faunal remains from Gough's Cave, Sun Hole and other contemporary sites (Kent's Cavern, Aveline's Hole, Kendrick's Cave). Despite the limited faunal sample, the original palaeodietary reconstruction is broadly consistent with our findings. The isotope values of the main protein sources consumed by the humans from both sites are consistent with those of red deer and bovines, and, for a single individual, with that of horse and red deer. Reindeer was postulated in the original reconstruction as a potential food source, but this seems very unlikely based on our isotope reconstruction and the archaeological remains.  相似文献   
994.
Is it possible to identify cooked, rather than burnt, bone? Mild heating (≤100 °C,1 h) – typical of cooking – does not lead to detectable changes in any biochemical parameter of bone yet measured. If it is only possible to detect charred bone, how is it possible to detect cooking in the archaeological record? In a previous paper (Koon et al., 2003, J. Arch. Sci.), we used a Transmission Electron Microscopy (TEM) based approach to investigate changes in the organization of the bone protein, collagen, as it is heated, using bone from heating experiments and short term burials. The work revealed that mineralized collagen, despite requiring aggressive treatment to gelatinise the protein (e.g. 90 °C, 240+ h), readily accumulates minor damage. We believe that the presence of mineral matrix stabilises the collagen enabling the damage to accumulate, but preventing it from causing immediate gelatinisation. Once the mineral is removed, the damage can be observed using appropriate visualization methods.  相似文献   
995.
The Dead Sea sediment holds the archives of a complex relationship between ever-changing nature and ancient civilisations. Here the detailed pollen analyses of core DS7-1SC (off-Ein-Gedi) are presented for the first time. The record covers the last 2500 years. The facies changes from halite (when no freshwater flows in the Dead Sea) to laminites (when rainfall provides sufficient inflow for the Jordan and subsidiary rivers) a couple of times through the record. The pollen diagram (supported by the facies change) shows a wetter Roman-Byzantine period, which allowed intensive arboriculture and a wetter period at the end of the XIXth and beginning of the XXth centuries, the latter in good relation with historical and instrumental data. Based on radiocarbon chronologies on several pollen diagrams along the western Dead Sea shore, the transition to drier climates and the transition to pastoralism are suggested to take place between a few decades before the Islamic period and close to this transition.  相似文献   
996.
In this paper, the characterization of Roman amphorae from the Porto dos Cacos (PC) and Quinta do Rouxinol (QR) workshops, in the Tagus estuary, dating to a period between the 1st and 5th century AD was carried out on the basis of instrumental neutron activation analysis data on 260 amphorae fragments, together with mineralogical compositional studies obtained by X-ray diffraction.  相似文献   
997.
Some radiocarbon dates for ancient Egypt have been significantly offset from the established historical chronology (see Bonani et al., 2001). In this paper, short-lived plant species collected in Egypt between 1700 and 1900 AD were used to investigate the possibility that the radiocarbon record had been influenced by reservoir effects. AMS radiocarbon measurements were made on 66 known-age samples, resulting in an average offset from expected values of 19 years. The implications of this minor discrepancy on the likelihood of a reservoir process are discussed, and the agreement of the data with recent models of radiocarbon seasonality is also considered.  相似文献   
998.
Scientists from the National Institute of Standards and Technology (NIST) worked in a collaborative partnership with archaeologists from the National Park Service's (NPS) Submerged Resources Center (SRC) to develop a finite element model (FEM) of the battleship USS Arizona. An FEM is a computer-based engineering model that calculates theoretical stresses, propagation of force, and shape changes to a structure under loads using thousands or even millions of individual elements whose individual responses are well understood. NIST researchers created an FEM of an 80 ft. (25 m) midships section of the Arizona site to analyze archaeological site formation processes on the sunken battleship, in particular to determine the current condition of the wreck and predict its future strength and structural integrity as it continues to corrode. The NIST's FEM study is one aspect of a larger project under the direction of the NPS, the USS Arizona Preservation Project, whose goal is to determine the nature and rate of corrosion affecting USS Arizona, and to model its long-term structural deterioration. The FEM incorporates findings from other key components of the USS Arizona Preservation Project, such as steel hull corrosion rates, structural surveys of the vessel, sediment compaction studies, and analysis of the concretion that covers the ship's hull, into a single tool that is being used to predict how the wreck will degrade in the future.  相似文献   
999.
Le Grand Abri aux Puces (GAP), located on the right bank of the Ouvèze River of southern France, has been known to contain well-preserved stone tools and faunal remains, but our work in 2008 was the first professional, controlled excavation at the site and has exposed at least 1 archaeological layer with a very rich and diverse faunal assemblage (23 macrofaunal species, as many for the microfauna, 27 land snail species), abundant charcoals (fragments are large and preserve small twigs with their pith and bark still intact), and stone tools with immaculate surface preservation (retaining their original freshness and preserving microscopic use wear). The information issuing from paleontology, micropaleontology, malacology, and anthracology all place the principle GAP human occupation unambiguously in a temperate climatic phase. Different biometric and biochronological characters of the fauna converge to place the layers found thus far from before the last glacial, and most likely in MIS 5e (127–117 kya). The lithic elements, mainly composed of tools of superior quality, demonstrating particular technical investment, and made from widely distributed raw material sources, lead us to hypothesize brief passages of hunting groups in the cave focused around an anticipated activity. This hypothesis will be refined and tested during further excavations.  相似文献   
1000.
One hundred and twenty-eight colourless glass tablewares from settlement contexts throughout the British Isles, dating from the mid-3rd to 4th century AD, were analysed by ICP-AES spectrometry. Three distinct compositional groups were identified based upon the use of different decolourisers and primary raw materials, with possible sub-groups within these. These compositions have distinct, but overlapping chronological ranges, suggesting colourless glass production in at least three, possibly more, centres in the late Roman period. The compositional analysis highlights the high degree to which recycling of glass was taking place during this late period. The chronological distribution of some of these compositions is more restricted within the British assemblages than is observed in other published assemblages from Western Europe. This distinction may indicate different supply patterns of glass to the Western provinces.  相似文献   
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