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981.
Investigation of modern biometric data indicates that it may be possible to distinguish wildcats from house cats in many instances. Applying the log‐ratio (log‐difference) technique to archaeological samples from medieval northern Europe, and to mixed samples of wildcats and house cats, shows that the differentiation may not always be clear, and the possibility that some samples include hybrids is discussed. The technique is applied to samples from the Orkney Islands to demonstrate that single wildcat specimens can be identified in small samples. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
982.
Faunal remains are commonly found in coprolites and provide direct evidence of animal consumption. An evaluation of hunter‐gatherer coprolites from the Southwest US shows that animal bone in coprolites can be used to assess patterns of hunting, food preparation, and general importance of small animals in diet. This is demonstrated by a comparison of faunal assemblages between two hunter‐gatherer sites with respect to small animal hunting strategies. The sites are Dust Devil Cave on the Colorado Plateau, an Archaic winter habitation, and Hinds Cave, a warm season Archaic habitation in the lower Pecos of Texas. The results indicate that small animal hunting varied regionally and seasonally. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
983.
Normal fusion of the acromion process in humans begins at about age 15 and should complete ossification by age 22–25. Os acromiale occurs when fusion of the acromial epiphysis does not follow its normal ossification pattern, resulting in the retention of a separate epiphyseal end to the acromial process. Depending on how the metaphyseal junctures fuse, differential size and shape of the unattached acromial segment is produced. As a result of shoulder anatomy and the mobile epiphysis, os acromiale is associated with shoulder impingement and rotator cuff problems. The purpose of this study is to document the frequency of os acromiale in the Robert J. Terry Collection and gain a perspective on the occurrence of os acromiale in this specific US population. The overall frequency of os acromiale in the sample of 1594 skeletons was 8.34%. This study also evaluates the prevalence of os acromiale between sexes and ancestral groups in the Terry Collection. Significant frequency differences in the expression of os acromiale were found between both ancestry and sex; the black male sample has the highest frequency (12.47%), with a lower occurrence in the black female sample (9.22%). The white sample exhibited observably lower frequencies, with the white males at 6.8%, and white females at 3.2%. Size and shape and side expression (laterality) showed no significant differences between the sexes. However, significant differences in laterality by ancestry were observed; black males exhibited 48.3% bilateral expression, while white males exhibited bilateral expression only 29% of the time and 54.8% had a right lateral expression. Based on the results presented in this study, it is suggested that there is a genetic causation for os acromiale, which may or may not be exacerbated by physical activity. The use of this anomaly as an additional non‐metric feature in inferring familial relationships and personal identification is discussed. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
984.
Ettore Majorana probably belongs to the most mysterious and most fascinating personalities of the recent physics history. Majoranas work shows also nowadays more than 60 years after its appearance an amazingly fresh reference to present physics problems. A short representation of Ettore Majoranas life and scientific work will be given in this article.  相似文献   
985.
X‐ray diffraction or scattering analysis provides a powerful non‐destructive technique capable of providing important information about the state of archaeological samples in the nanometer length scale. Small‐angle diffraction facilities are usually found at synchrotron sources, although the potential of a laboratory source is also described. Specific examples of analysis using X‐ray diffraction of historic parchment, archaeological bone, a Central Mexico style pictograph and microdiffraction of calcified tissues are used to show the scope and versatility of the technique. Diffraction data is capable of giving fundamental structural information as well as quantifying the remodelling of structures influenced by environmental factors.  相似文献   
986.
Different black pigments of natural origin (mineral or organic) have been examined by means of several analytical methods (colour measurements, elemental analysis and structural analysis). The results, after being compared with each other, then served as reference points in the study of the ‘Black Frieze’ of the cave of Pech Merle (Lot). After that, colour measurement was investigated in situ on the paintings as a means of displaying small differences (in hue or chroma) between the black colours. The aim of this study was to verify several hypotheses concerning the techniques used by the painters of Pech Merle, and specifically by the one(s) of the Black Frieze. A first objective was that of identifying the nature and, if possible, the origin of the black pigments used in these figures. A second objective was that of determining in which parts of the frieze one or the other (or one and the other) had been used; and the final objective was to provide new technical information that might help us better to understand how the Pech Merle frieze was produced, whether by a single painter and in one episode, for the most part, or, on the contrary, in several episodes and by a succession of different painters.  相似文献   
987.
Cluster analysis is the most widely used multivariate technique in archaeometry, with the majority of applications being exploratory in nature. Model‐based methods of clustering have their advocates, but have seen little application to archaeometric data. The paper investigates two such methods. They have potential advantages over exploratory techniques, if successful. Mixture maximum‐likelihood worked well using low‐dimensional lead isotope data, but had problems coping with higher‐dimensional ceramic compositional data. For our most challenging example, classification maximum‐likelihood performed comparably with more standard methods, but we find no evidence to suggest that it should supplant these.  相似文献   
988.
P. Mirti  P. Davit 《Archaeometry》2001,43(1):19-33
Sherds of Campanian pottery were studied by SEM‐EDX. SEM images show that slips of Campana C are scarcely sintered and are thicker than the well vitrified coatings of Campana A and B and imitations of Campana B. Slips of products with a grey slip on a grey body are very thin and well vitrified. EDX analyses indicate that slips are richer in aluminium and iron, and poorer in silicon and calcium, with respect to the bodies. Higher potassium is also found in all of the coatings except those of Campana A. Here relatively high sodium makes the total alkalis comparable with those of the other products, except Campana C, where it is somewhat lower. Measurement of thermal expansion and X‐ray powder diffractograms suggest that firing temperatures were mostly in excess of 900°C, but some samples of Campana C seem to have been fired below 800°C.  相似文献   
989.
990.
Among the Nigerian cast copper‐alloy artefacts, the chronology of the Benin memorial heads has been the most fully worked out. Therefore, a study focused upon their elemental compositions is particularly likely to be interpretable in terms of development of the alloys used in their making. The elemental analyses, both published and unpublished, of 66 Benin heads, supplemented with seven analyses of some artefacts excavated from a well‐dated, very early Benin site, have been collected, analysed statistically and computed to the elemental analyses of 11 heads and figures from Udo. All but a very few of the Benin heads and artefacts separate into five compositional groups, indicating a chronological sequence of different alloying traditions. All but one of the Udo objects fall into a distinctly separate compositional group, together with two Medicine heads. The compositional groups correlate remarkably well with the stylistic types proposed by Dark.  相似文献   
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