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1.
The soluble and exchangeable ions for a soil profile from the Roonka archaeological site. Lower Murray Basin, South Australia, are compared with the total elemental content of the soils. Since the chemical composition of post-mortem ionic substitution phases and secondary minerals in archaeological bone will depend on the availability of ions to the soil solution under field conditions, it is suggested that models addressing diagenesis in bone employ soluble and exchangeable ions rather than total elemental soil data.  相似文献   
2.
Biogeographers, ecologists, palaeontologists, and conservation managers often deal with checklists in which not all individuals have been identified to a species level, or the accuracy of species identification is questionable. Is it possible and credible to investigate species richness based on such checklists? Studies on macrofauna in the Far Eastern seas, eastern Arctic seas, and adjacent waters of the Pacific and Arctic Oceans suggest that in different habitats and for diverse taxa, species, and higher taxa richness strongly correlate with each other and increase with an expansion in the study area and sample size according to the species–area law. Such an increase is higher in the bottom zone than in the pelagic. Species and higher taxa richness also show a decrease from lower to higher latitudes, which is in line with the Humboldt–Wallace’s law. According to Willis’ law and self-similarity in the organisation of taxonomic levels, species richness can be assessed based on the genus, family, and order richness. In other words, supraspecies richness itself can tell us the same as species richness and therefore certain global patterns revealed at the species level may also be revealed at the supraspecies level. Such a concordance in general trends among richness parameters at different taxonomic levels in practice implies that species richness can be studied based on lists that lack species identifications or lists with doubtful species identification. We suggest bolder use of supraspecies richness in science and practice, discussing the disadvantages and advantages of this approach.  相似文献   
3.
Up until the end of 2018, extreme right-wing parties and their anti-immigration discourse, now a common occurrence in other European countries, had not appeared on the Spanish political scene. However, in December of that year, the Spanish extreme right-wing party VOX reversed this trend and made significant electoral gains in the Andalusian regional elections. This phenomenon has led us to analyse, in this study, the role played by contextual factors (i.e., out-group size, territorial concentration of the immigrant population, demographic change in settlement locations, aggregated educational level and unemployment rate among the receiving society) in the rise in the number of VOX voters. To achieve this, VOX's results from all the polling stations in Andalusia contained in its 5946 census tracts were analysed. At the same time, each census tract was associated with its demographic, economic and educational data, and their relationship was analysed using a multilevel analysis with Mplus. The results show that the presence of economic immigrants is indeed associated with a higher percentage of VOX voters in Andalusia. However, despite this general trend, those census tracts with a high territorial concentration of Maghrebi immigrants are associated with a lower percentage of support for this extreme right-wing party. The opposite is found for Romanian immigrants. Moreover, areas with larger percentages of people with a high level of education influenced greater support for VOX. Thus our findings suggest the traditional explanations for the increased support for extreme right-wing parties in northern Europe do not provide clear patterns that can be extrapolated to Andalusia.  相似文献   
4.
Human bones from Late Eneolithic graves and Bronze Age settlement pits in Moravia (Czech Republic) were studied to reconstruct their post-mortem histories based on the distribution of their microbial destruction. Backscattered electrons in a scanning electron microscope (BSE-SEM) were used for visual assessment of bioerosion. Visual data from the histological analysis were transformed into quantitative data using the Waikato Environment for Knowledge Analysis (WEKA) toolkit. The results show that the presence of bioerosion is different between the two groups of samples. The bones from settlement pits display extensive bioerosion whereas the bones from graves display no or arrested bioerosion. The absence of bioerosion in graves is most probably linked with tomb burials of Corded Ware Culture. Given the tombs are frequently not preserved archaeologically, the state of bone bioerosion may serve as an indicator of their existence.  相似文献   
5.
A review of recent anthropological research deriving behavioral inferences from analyses of human skeletal remains focuses on interpretations of diet, social organization, population structure and migration, activities, activity levels and occupation, and warfare, violence, and death in the prehistoric and historic Americas. Critical evaluation of these inferences shows that some of them suffer from inadequate supporting evidence, lack of consideration of alternative hypotheses, or absence of clear methods for deriving and testing these inferences. Overall, however, the potential for behavioral reconstruction from skeletal analysis is great. Behaviors leaving more direct effects on bone such as dietary preference, warfare, and some activities produced the most secure inferences when derived from populational samples and supported by supplementary evidence. Human skeletal remains represent important resources for the reconstruction of behavior.  相似文献   
6.
A vertebra of a Brown Bear (Ursus arctos) is described from the Mesolithic settlement Star Carr. This is the first record of the species from the site. The presence of Brown Bear in a Preboreal/Boreal deposit is an important addition to the early Mesolithic fauna of Britain. A comparison with contemporary Danish material shows that the bone from Star Carr falls within the wide size range of the Danish subfossil Brown Bear. In Denmark the species decreases in number from Boreal to Atlantic time, and finds are extremely scarce in Britain during the same time interval. This is probably due to the major eustatic sea level rise, which isolated Britain and Sjælland, preventing new immigration, and to vegetational changes restricting the preferred habitats of the Brown Bear.  相似文献   
7.
The literature shows that market size favours firms’ vertical disintegration because it reduces transaction and knowledge coordination costs. The existing evidence is based primarily on cross-sectional data and on the manufacturing sector, with little or no attention is given to longitudinal data and services. This paper estimates the effect of urban size on the purchase of service inputs by knowledge-intensive business service firms located in the metropolitan region of Milan. Relying on a rich panel dataset, and adopting different econometric techniques to overcome endogeneity, we find a positive and statistically significant effect of increased urban population on the degree of KIBS vertical disintegration only when urban size is measured at the province level. We also find that this effect holds particularly in the case of traditional professional- rather than technology-related activities.  相似文献   
8.
The studies on the finishing technique of the stone monuments in Persepolis (Iran) are part of the archaeological project jointly launched in 2008 by Iran and Italy, named ‘From Palace to Town’. The first experimental results, obtained on a very limited number of samples, revealed that the Achaemenid builders and sculptors used a white pigment, a kind of bone white, calcium fluorapatite, obtained by burning animal bones, to hide the dark grey colour of the stone. In order to verify these unexpected results, a new campaign was implemented to analyse a much larger number of samples. XRF spectrometry, a non‐destructive technique, was used and the experimental results were further elaborated by PCA. The presence of a white superficial layer was confirmed, and the use of fluorapatite was confirmed as well, but only on monuments attributed to the Xerxes period or later, while in the earlier monuments the white layer was obtained using gypsum.  相似文献   
9.
新中国土地改革后新富农产生的规模与分布研究   总被引:1,自引:0,他引:1  
从土地改革结束到农业集体化高潮前夕,新富农的出现从全国范围来看是稀少而缓慢的。在各省之间,农民的富裕程度与新富农比重大小关系不明显,但在同一地区内来看,两者呈现正相关关系。同时,在农业合作化程度较高亦即是较早对新富农采取限制政策的地区,新富农的比重并不一定低于甚至高于其他地区。这说明多种因素对新富农的产生、发展发生作用,单因素的分析不能解释清楚新富农这个复杂的社会经济问题。  相似文献   
10.
Teeth are often the preferred source material for isotopic and genetic assay involving ancient biomolecules. The assumption is that dental tissue preserves better due to its anatomically protected location, the enamel cap, and lower porosity compared to bone. However, this assumption has not been widely tested. Some similarities in diagenetic processes are to be expected due to similarities in structure and chemical composition of dentine and bone. This has led to the suggestion that bone can be used as an indicator of dental preservation, as a pre‐screening technique in the selection of suitable samples for biomolecular studies. Thus, direct testing of the correlation between bone and tooth preservation and diagenesis is needed. This paper reports the results of the histological characterization of diagenetic alterations within 25 human femur–tooth pairs, from a Medieval to modern (AD 1850) cemetery in Eindhoven, the Netherlands. The results showed that teeth do indeed preserve better overall, but not always, and that this was dependent on the main diagenetic factor(s) at the burial location. Furthermore, good correlations are found between the microstructural preservation of bone and teeth; similar processes of decay were observed within bone and teeth of the same individual. Overall, the study demonstrated that histological analysis of bone is useful for the identification of degradation processes that affect biomolecular preservation in skeletal material. In this way, sample selection and analytical strategies can be optimized. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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