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31.
微生物是影响古代壁画安全保存与展示的一个重要因素,其检测是壁画保护研究的重要环节。分子生物学技术通过直接分析微生物遗传物质确定种属,可以避免传统检测技术必需的微生物培养过程,不仅快速、全面,更重要的是能够确定主要致病菌。本研究用分子生物学技术检测中国北方两个5世纪壁画墓,确定导致壁画菌害的主要种群为假诺卡氏菌(Pseudonocardia sp.),为微生物病害治理和预防提供了基本依据。  相似文献   
32.
The zooarchaeological study of small-vertebrate consumption requires a taphonomical approach to differentiate animal bones that were incidentally incorporated from those that were intentionally exploited in the past human subsistence. In order to make this distinction, the relationship between archaeological small-rodent burned bones and prehistoric human behavior was explored using an experimental cooking study as a modern analogue. During the cooking experiment the entire carcasses of three guinea pigs (Cavia porcellus) and two yellow-toothed cavies (Galea leucoblephara) were placed in the coals of an open fire that simulate a real campfire, rotating their positions until the meat was completely cooked. Subsequently, the intensity of burning damage and the loss of skeletal elements were analyzed at macroscopical levels. The data was used to identify cooking evidence in the Ctenomyidae and Caviidae rodent bones recovered from Quebrada del Real 1 (ca. 6000-300 BP, Córdoba, Argentina). Remarkable similarities between the archaeological and analogical records were found, including the distinctive burning pattern on the distal extremities of the unmeaty long bones (e.g, radii and tibiae), the high frequency of broken incisor teeth and the loss of autopodium elements. Based on these comparative results, it is suggested that the small-rodent assemblages of QR1 were primary accumulated by humans though butchery, cooking and consumption related activities. Extending this study to other archaeological sites in South America may help to identify the prehistoric bone collectors of these small-animals.  相似文献   
33.
The article assesses the effects, direct and indirect, intended and unintended, of the 1993 national electoral reform and the results of the 1994 general elections in Italy. It shows that the new system is not an eccentric compromise, and that those who forecast either its unworkability or its evil consequences were mistaken. However, in evaluating the success of the reform with respect to the ambitions which were held for it, it concludes that the reform was a predictable failure. The article then explores the role played by the electoral reform in the unexpected electoral success of the Polo della Libertà, the emergence of Forza Italia, and the ability of Berlusconi to strike a compromise with two such different parties as La Lega and the AN.  相似文献   
34.
The feasibility of using output-only model-free wavelet-based techniques for damage detection in reinforced concrete structures subjected to seismic loads is explored through the analysis of the results of a full scale shake table test of a reinforced concrete bridge column recently performed at the NEES Large High Performance Outdoor Shake Table. The evaluated approaches are based solely in the analysis of the acceleration time histories recorded in the structure. The viability of using numerical models to validate this type of damage detection methodologies is also evaluated. Wavelet analyses were capable of identifying the rebar fracture episodes and partially identified the frequency shifts in the structure as the inelastic demand increased. It was also found that, depending on the methodology employed, the use of numerical models to validate damage detection techniques can oversimplify the actual problem and/or induce spurious irregularities.  相似文献   
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The analysis of dietary traits of ungulates through tooth microwear and mesowear has been applied to archaeological sites to investigate seasonal changes in settlements by hunter–gatherers. In this paper we propose to test the hypothesis that tooth microwear (combined to mesowear) is able to indicate seasonality in the diet of extant ungulates in arid habitats (semi-deserts or steppe). The material analyzed comes from six faunal monospecific assemblages of guanaco (Lama guanicoe) resulting from a mass mortality event in winter 2000 near the Cardiel Lake in Southern Patagonia (Province of Santa Cruz, Argentina). Mesowear results indicate that the guanacos from the Cardiel Lake area are mixed feeders, and thus, have a diet that shifts seasonally. Moreover, microwear analysis supports the hypothesis that tooth microwear is able to indicate seasonality in the diet of extant guanaco in arid habitats. The pattern is clear for the winter sample and needs to be confirmed for a summer sample. Consequently, tooth microwear is proposed as a new potential proxy for detecting seasonal occupation in archaeological sites in Patagonia and other arid environments.  相似文献   
37.
Konservat-Lagerstätten are a source of insurmountable information on the diversity of fossil assemblages during the lower Palaeozoic. Soft-bodied fossils are especially rare in South America, but a new locality has been discovered from the Middle Ordovician of Peru that has produced the fairly well-preserved possible palaeoscolecidan Juninscolex ingemmetianum gen. et sp. nov. The distinctive characteristics of this worm make it similar to European taxa within the group.  相似文献   
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During the last glacial maximum, the west European modern humans adapted to adverse conditions and their populations subsisted exploiting the natural resources available. Fish were always present as a source of animal protein, although their importance in the human diet and their contribution to the expansion of humans has not been fully explored. Based on the compilation of zooarchaeological evidences from north Spanish sites we have discovered a constant pattern of exploitation of freshwater fish (Salmonids) with high incidence in the human diet during the Upper Paleolithic. Shifts in the exploitation of marine resources can be explained by climate-related geographical changes. The characteristics of salmonids that make them target species for supporting human survival in adverse climate periods are identified and discussed.  相似文献   
40.
We promised in our last editorial (Puga and Wrigley, 2004) toreturn with news of the Journal's performance in the ISI citation‘impact factor’ rankings. That is to say, to givereaders the opportunity to gauge how the Journal is beginningto fare in the ‘market place for ideas’. June 2005saw the release of the ISI 2004 Journal Citation Reports (JCR)—thefirst year Journal of Economic Geography appears in the JCR.The result (Table 1) is remarkable. On the basis of citation‘impact factor’, Journal of Economic Geography entersthe rankings as No. 1  相似文献   
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