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A comprehensive remote sensing survey of AlUla County in north-west Saudi Arabia has revealed 32 examples of the ancient, stone-built animal traps known as ‘kites’. Noting that most (27) are located on the Ḥarrat ʿ Uwayriḍ, a satellite survey of parts of that lavafield outside of AlUla County was undertaken, identifying a further 175 kites. These show commonalities with ‘V-shaped’ kites previously identified in mountainous areas along the western extents of the Arabian Shield in the Sinai Peninsula, Negev Desert and south-west Saudi Arabia. A study of the form and placement of these kites in their ecological and geological contexts suggests that they are representative of a distinct complex, exhibiting sophisticated morphological adaptations to target specific games over similar terrain.  相似文献   
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The detection and identification of protein residues from archaeological artefacts has been the subject of considerable controversy over the past two decades, this controversy spurring the application of a range of different analytical methods. Part of the debate surrounds the ability of the methods to uniquely identify original proteins. Another is the apparent contradiction between the ease of extraction in the laboratory of residues that have managed to survive in sediment over millennia; some studies use simple solvents including water, whilst others claim that efficient extraction requires the destruction of the artefact.Desorption electrospray ionisation mass spectrometry (DESI-MS) offers the potential to directly analyse proteins bound to the surface of artefacts. The method permits desorption of analytes under ambient conditions directly from a wide range of surfaces with little or no sample preparation. This has already led to its application in a range of areas, including forensic analysis of trace levels of narcotic drugs. It does not require destruction of the artefact (e.g. by drilling or dissolution) and can work in concert with other methods (for instance it could be used as a screening tool prior to lipid extraction).Here we report the construction of a DESI-MS interface and consider the potential of the method to contribute to the debate surrounding the preservation of proteins on artefacts. The DESI-MS interface was fitted to a conventional ion trap mass spectrometer and tested using peptides and proteins artificially applied to the surface of flint flakes and potsherd samples. A range of intact proteins was analysed; the DESI interface identified test proteins up to a maximum molecular weight of approximately 20 kDa. Peptides generated from these and larger proteins could be detected using DESI-MS following tryptic digestion in situ. The collected data allowed identification of the originating proteins. The potential applications to archaeological science of this new analytical tool are discussed.  相似文献   
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The earliest evidence of prehistoric religious practice in China found so far comes from excavations at Beifudi, about 120 km south of Beijing, in the form of votive offerings and porcelain sorcery masks dated to the period 8000–7000 yr BP. These finds are part of a rich Neolithic site located on the second river terrace on the north shore of the Yi River. This paper presents results of pollen analysis of part of a sediment profile from a depression at the edge of first terrace towards second terrace, a few hundred metres away from the main archaeological finds. A sequence of marked changes in environment occurred between 9000 cal yr BP and 6000 cal yr BP, and dating evidence suggests strong associations with the ebb and flow of human activity in the area. The first phase of activity on the site begins at around 8000 cal yr BP, towards the end of a period of relatively dry, cold environmental conditions. Between 7800 cal yr BP and 7400 cal yr BP, the first clear evidence of cereal cultivation appears in the pollen record. Rich archaeological finds occur during the same time period, suggesting local prosperity. This first phase of the Beifudi culture ends at 7300 cal yr BP, when warmer and wetter conditions are inferred and wetland areas expand, reducing the area available for crop cultivation near the site. A return to drier and cooler conditions from 6900 cal yr BP corresponds with the second phase of apparent prosperity in the archaeological record from Beifudi. This phase ends at around 6500 cal yr BP, at the start of another shift towards wetter conditions in the flood plain environment. The pollen record suggests that environmental conditions in the flood plain were a major determinant of human activity at Beifudi in the early-mid Holocene.  相似文献   
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Excavations at the site of Langley’s Lane, Bath and North-East Somerset, have revealed an important sequence of Late Mesolithic activity focused around an active tufa spring. The sequence of activity starts off as an aurochs kill and primary butchery site. Culturally appropriate depositional practices occur through the placement of a selection of bone in the wetland of the spring and the digging of pits around the spring margins. The spring at Langley’s Lane continued to be visited and more animal bone and lithic material was placed in the wetland. Finally, visits to the site involved yet more formalized activity in the form of pit digging and the creation of a stone surface. Activities such as these are difficult to locate in the archaeological record and Mesolithic ritual activity rare, making this a site of some significance to studies of Mesolithic NW Europe.  相似文献   
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Excavated human bone was exposed to aqueous solutions containing high concentrations of a single added metal ion in order to examine the extent of introduction of contaminating materials during burial. Variables included pH, temperature, ion concentration, state of bone (whole or crushed), structure of buffer, and counterion. Calcium and sodium showed little increase, and even a decrease in some cases. Strontium, zinc, lead, and magnesium showed large increases probably through heteroionic replacement of calcium. Manganese, aluminum, and potassium showed increases, particularly under neutral conditions, probably through infiltration into voids and defects.  相似文献   
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