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61.
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   
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A geophysical survey at the pyramid complex of Senwosret III at Dahshur sought to determine the suitability of magnetometry and electromagnetic induction (EMI, or conductivity) for mapping the area where several ancient boat-burials were found in the 1890s. At least one boat reported at the time of excavation remains unaccounted for. Tests demonstrated that magnetometry does detect subsurface structures of stone, fired brick, and unfired brick under current site conditions. Data indicated areas of geological activity as well as unexcavated archaeological remains, though no definitive traces of boat burials. No excavation was undertaken but another survey season is planned.
© 2009 The Authors  相似文献   
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We report the recovery of short fragments of PCR amplifiable ancient DNA from exoskeletal fragments of the grain weevil Sitophilus granarius (L.) extracted from Roman and medieval deposits in Northern England. If DNA preservation in archaeological insect remains is widespread then many applications in the spheres of evolutionary studies and archaeology can be conceived, some of which are outlined.  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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Intensive agricultural systems interact strongly and reciprocally with features of the lands they occupy, and with features of the societies that they support. We modeled the distribution of two forms of pre-European contact intensive agriculture – irrigated pondfields and rain-fed dryland systems – across the Hawaiian archipelago using a GIS approach based on climate, hydrology, topography, substrate age, and soil fertility. Model results closely match the archaeological evidence in defined locations. On a broader scale, we calculate that the youngest island, Hawai'i, could have supported 572 km2 of intensive agriculture, 97% as rain-fed dryland field systems, while Kaua'i, the oldest island, could have supported 58 km2, all as irrigated wetland systems. Irrigated systems have higher, more reliable yields and lower labor requirements than rain-fed dryland systems, so the total potential yield from Kaua'i (49k metric tons) was almost half that of Hawai'i (97k metric tons), although Kaua'i systems required only 0.05 of the agricultural labor (8400 workers, versus 165,000 on Hawai'i) to produce the crops. We conclude that environmental constraints to intensive agriculture across the archipelago created asymmetric production efficiencies, and therefore varying potentials for agricultural surplus. The implications both for the emergence of complex sociopolitical formations and for anthropogenic transformation of Hawaiian ecosystems are substantial.  相似文献   
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The growth of modern nationalism can be attributed to structural causes, especially the growth of the strong bureaucratic state that penetrates society, creating cultural uniformity and national identity. But structurally based nationalism need not be very intense, or constant; even when institutionalised in periodic formal rituals, it can be routine, low in emotion – even boring. We need to explain sudden upsurges in popular nationalism, but also their persistence and fading in medium‐length periods of time. Nationalist surges are connected with geopolitical rises and falls in the power‐prestige of states: strong and expanding states absorb smaller particularistic identities into a prestigious whole; weaker and defeated states suffer delegitimation of the dominant nationality and fragment in sudden upsurges of localising nationalities. Passing from macro‐patterns to micro‐sociological mechanisms, conflict producing solidarity is a key mechanism: dramatic events focus widespread attention and assemble crowds into spontaneous ‘natural rituals’ – mass‐participation interaction rituals, as distinct from formal rituals. Evidence from public assemblies and the display of national symbols following the terrorist attacks of 11 September 2001 (9/11) shows an intense period of three months, then gradual return to normal internal divisions by around six months. Spontaneous rituals of national solidarity are produced not only by external conflict but by internal uprisings, where an emotional upsurge of national identity is used to legitimate insurgent crowds and discredit regimes. Although participants experience momentary feelings of historic shifts, conflict‐mobilised national solidarity lives in a 3–6‐month time‐bubble, and needs to institutionalise its successes rapidly to have long‐term effects.  相似文献   
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