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A pair of mandibular rami from a brown bear (Ursus arctosL.) was found at the rock shelter of the Grande-Rivoire in the Castelnovian level. Both exhibit a peculiar deformation affecting the bone between the first and second molars and the roots of these teeth.The perfect symmetry of this deformation, the absence of pathological features, and the misplacement of the teeth suggest that a thong had been placed around the mandible while the animal was young; the mandible then grew around the thong.The interest of this find is that it both demonstrates the taming of a bear and the complexity of the relationships between humans and animals during the late Mesolithic.  相似文献   
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Carbon and nitrogen stable isotope values were measured from bone collagen extracted from archaeological Nubian human (n = 54) and faunal (n = 61) populations from the site of Kerma, Sudan. Collagen suitable for isotopic analysis was extracted from 22 faunal and 48 human samples from the Eastern cemetery site, dated to the Middle Kerma (c. 2050–1750 BC) and Classic Kerma (c. 1750–1500 BC) periods respectively. The isotopic data indicate that the human dietary regimen included a mix of C3 and C4 plant-derived components, with a larger C4 component than previously reported in archaeological Egyptian Nile Valley populations. Elevated δ15N values are attributed to consumption of dietary resources from a 15N-enriched terrestrial ecosystem. The faunal isotope data also indicate the consumption of C3 and C4 plants. The large range of δ13C values measured in both the human and faunal samples supports previous work suggesting that a significant portion of the populations buried at Kerma may have originated elsewhere, further confirming the Nile Valley as a major corridor for population movement in the region.  相似文献   
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We propose a geoadditive negative binomial model (Geo‐NB‐GAM) for regional count data that allows us to address simultaneously some important methodological issues, such as spatial clustering, nonlinearities, and overdispersion. This model is applied to the study of location determinants of inward greenfield investments that occurred during 2003–2007 in 249 European regions. After presenting the data set and showing the presence of overdispersion and spatial clustering, we review the theoretical framework that motivates the choice of the location determinants included in the empirical model, and we highlight some reasons why the relationship between some of the covariates and the dependent variable might be nonlinear. The subsequent section first describes the solutions proposed by previous literature to tackle spatial clustering, nonlinearities, and overdispersion, and then presents the Geo‐NB‐GAM. The empirical analysis shows the good performance of Geo‐NB‐GAM. Notably, the inclusion of a geoadditive component (a smooth spatial trend surface) permits us to control for spatial unobserved heterogeneity that induces spatial clustering. Allowing for nonlinearities reveals, in keeping with theoretical predictions, that the positive effect of agglomeration economies fades as the density of economic activities reaches some threshold value. However, no matter how dense the economic activity becomes, our results suggest that congestion costs never overcome positive agglomeration externalities. Nuestra propuesta se basa en un modelo geoaditivo binomial (Geo‐NB‐GAM) para datos de recuento regionales (regional count data) que nos permitan abordar simultáneamente distintos temas metodológicos importantes como la concentración espacial (clustering), no linealidades y sobre‐dispersión. Este modelo es aplicado al estudio de determinantes de localización de nuevas inversiones de tipo greenfield internas (inward greenfield investments) que se dieron entre 2003 y 2007, en 249 regiones europeas. Luego de presentar el conjunto de datos y de mostrar la presencia de sobre‐dispersión y agrupación (concentración) espacial, examinamos el marco teórico que motiva los determinantes de localización incluidos en el modelo empírico, y resaltamos algunas de las razones por las que las relaciones entre ciertas co‐variables y la variable dependiente podrían ser no lineales. La sección subsiguiente comienza con descripción de las soluciones propuestas por la literatura anterior para abordar la concentración espacial, no linealidades, y sobre‐dispersión, para luego presentar el Geo‐NB‐GAM. El análisis empírico muestra el buen desempeño del Geo‐NB‐GAM. Particularmente, la inclusión del componente geo‐aditivo (una superficie de tendencia espacial suavizada) nos permite controlar heterogeneidades espaciales no observadas que inducen a la concentración espacial. Al permitir no linealidades se revela ‐continuando con las predicciones teóricas‐ que el efecto positivo de las economías de aglomeración se desvanece a medida que la densidad de las actividades económicas alcanza un umbral de valor. Sin embargo, sin importar cuán densa llegue a ser la actividad económica, nuestros resultados sugieren que los costes de congestión nunca superan las externalidades de aglomeración positivas. 本文提出了一种应用于区域统计数据的负二项式地理加性模型,它能够同时处理包括空间聚类、非线性和过度离散等多种重要的方法论问题。将该模型应用于2003‐2007年的249个欧洲案例区,探讨其内部绿地投资的区位因子。在揭示了数据集样本分布具有过度离散与空间聚类特征后,我们对所构建的关于区位驱动因子的实证模型进行了核查,以确定是否遗漏重要变量,并高亮显示为何有些变量与因变量的关系可能是非线性的。本文后续部分首先描述了已有文献在解决空间聚类、非线性与过度离散等情景下的解决方案,并简要介绍了本文的Geo‐NB‐GAM模型。实证分析表明,该模型具有良好的模拟效果,尤其是地理加性成分(一种平滑的空间趋势面)在处理包括空间聚类在内的未被关注的空间异质性。非线性模型揭示出集聚经济的正向效应,随着经济活动密度阈值呈衰减趋势,这一点和理论预测是一致的。然而,本文结果显示无论经济活动的密度呈现何种变化,正向集聚的外部效应仍大于拥挤成本。.  相似文献   
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Children's independent mobility (IM) lacks a standardised definition and measurement protocol. Interactive mapping applications can capture geographically defined mobility data. In this study of 219 children, independent parental licences (IM Licence) and allowances to travel to certain locations unsupervised (IM Index) were collected through a questionnaire, and compared to IM-roaming areas derived from the Visualisation and Evaluation of Route Itineraries, Travel Destinations, and Activity Spaces (VERITAS-IM) mapping application. Significant relationships were found between the VERITAS-IM-derived measures and traditional measures of IM (IM Licence and IM Index). Results suggest the perceived degree of children's IM is heavily dependent on the assessment method and a combination of methods should be considered.  相似文献   
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The results of an analysis of pigments used in slips and designs deployed in ceramic assemblages recovered from archaeological sites located in different environments, expressing the socio-historical process developed in the regions of Fiambalá and Chaschuil (Catamarca, Argentina) during the last 1500 years are presented. The sample, formed by fragments of different ceramic styles and natural pigments, was analysed via Raman spectroscopy and X-ray diffraction. Results indicate the continuity in use of certain pigments (mainly hematite for red hues and Mn oxides in combination with magnetite for black paints) within the different socio-political organizations that inhabited the region from the first to the 14th centuries ce , in spite of the diverse shades of colour, which suggests an intentional search linked with their cultural conventions. For the Inca Period, this scenery of continuities in minerals employed for reds and blacks is complemented by the use of new compounds (Ti oxide, apatite and gypsum) in order to generate the ‘cream’ tones applied as slips, all of which have not been identified for previous moments.  相似文献   
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This paper presents an assessment of all known dental and mandibular morphological criteria for differentiating sheep (Ovis aries) and goats (Capra hircus) using for the first time an archaeological sample of complete caprine skeletons (90 sheep and 13 goats) from burials at Kerma (Sudan, 3rd and 2nd millennia BC). The species determinations were assessed using cranial and post-cranial morphological criteria. Consequently, the reliability (percentage of correct determination) and efficiency (complementary percentage of intermediate scores i.e. neither sheep nor goat) of 38 individual dental criteria could be fully assessed using a prehistoric homogeneous domesticate population. We demonstrate that, for this sample, individual criteria for lacteal teeth are more reliable for sheep (sheep: 95 ± 3%) than the adult premolars (85 ± 5%) and molars (sheep: 88 ± 2%), whereas for goats premolar criteria were more reliable (83 ± 12%). For efficiency, lacteal dental criteria are better (goat: 97 ± 5%; sheep: 95 ± 3%) than those for premolar (goat: 85 ± 10%; sheep: 79 ± 5%) and molar (goat: 82 ± 6%; sheep: 83 ± 2). We also demonstrated that most isolated teeth can be determined with less than 10% error. However, on average, within specific age classes (0–1 year, 1–4 years and more than 4 years), isolated teeth increased in reliability and decreased in efficiency. The average reliability of the criteria for complete mandibles for each age class for goats and sheep was 100%, when the efficiency was 67, 40 and 50% for goats and over 90% for sheep. This is due to the effect of age on the efficiency of isolated criteria and the poor performance of specific criteria mainly those P3, M1 and M2. We conclude that separate species kill-off profiles are possible. The effect of age on dental criteria would not significantly change the interpretation for specific subsistence strategies focused on one particularly species.  相似文献   
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