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Examining histological sections obtained from human bones from Iron Age archaeological excavations (about third to fifth century BC , Alfedena and Sulmona, central Italy), the authors show the presence of an amorphous, afibrillary substance inside the osseous canaliculus in decalcified sections. This substance has shown unusual chromaffinity to staining using the Schmorl method with thionine and phosphowolframic acid. It is probably formed by acid mucopolysaccharides obtained from a transitory betametachromasia with toluidine blue staining at neutral pH. This metachromasia persists after digestion in bacterial collagenesis, but disappears after digestion in bovine testicular jaluronidasis. These reactions indicate that the endocanalicular substance may represent well-kept remains of a Rouget-Neumann sheath, which surrounds cytoplasmic extensions of osteocytes.  相似文献   
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This article examines the under-studied film productions known in Peronist Argentina as “docudramas”. Placing documentary elements within a fictional plot, docudramas marked a significant change in the state propaganda machine and were used as a new vehicle to influence social habits. I focus particularly on Soñemos [Let’s Dream], a short film directed in 1951 by Luis César Amadori to showcase urban reforms. Through an analysis of Amadori’s docudrama in regard to its representation of the Children’s City built by the Eva Perón Foundation, I discuss relationships between entertainment, the constitution of a political hegemony, and modernisation. With film techniques such as the dissolve, Soñemos depicts the Children’s City as an enterprise capable of delivering material happiness and amplifies the narrative of a fairy tale come true promised by Evita’s social service programmes. Ultimately, the docudrama affirms the central role played by the state in the definition of the “right to a home” – from supportive benefactor to constitutive replacement.  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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A relevant subject of study in the sphere of ancient Egyptian painting technology is given by the evolution of the palette across New Kingdom, Ptolemaic and Roman periods. Functionally to secondary factors such as geographic occurrence of minerals and type of associated surface, the employment of certain painting materials provides relevant insights into particular issues such as relative dating of the object and social rank of the owner. The Book of the Dead of Amenemhet (ROM 978 × 43.1, middle Ptolemaic Period) has been analysed at the Department of Restoration and Conservation of Archivals, Graphics and Book Illumination of the Cologne Institute of Conservation Sciences (Germany). Together with visible reflectance spectroscopy, digital and optical microscopy, devices such as XRD, SEM-EDX and FT-IR have been successfully employed for the characterization of the pigments from the polychrome funerary papyrus displayed at the Royal Ontario Museum, Toronto (Canada). The present research took place within a series of investigations performed at the CICS, devoted to the interdisciplinary study of funerary Egyptian papyri dating from the early 18th Dynasty onwards.  相似文献   
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This article examines the flexibility of the notabile model in different circumstances and time periods. The idea of a notabile cannot be restricted to only a few cases as there are many examples of notabili who, despite not having social and family origins of the classical notabile type, tend to assume the same behavioural and cultural patterns in managing power. The patterns usually considered typical of a notabile are often linked to landed property and the professions, but there are many other cases that suggest that the qualities of the notabili change in different historical and political moments, and are easily adapted to changing social and environmental circumstances. Even when they do not seem to fit directly into the classical model, over time those original features are still evident.  相似文献   
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The aim of this article is to understand the triggering factors of new firm growth in high-tech environments (life science, knowledge-intensive business services [KIBS] and engineering) by studying a representative sample of high-growth Italian start-ups. Our empirical research uses the information gathered during direct interviews with managers through a semi-structured questionnaire, which was presented to 382 new Italian firms. Considering the characteristics of new firms, this article summarizes the key growth factors. Investment in acquiring new competencies both in technology and marketing, development of dynamic capabilities (investment in human resources and new routines) and access to external knowledge and information sources emerged as significant.  相似文献   
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Waterlogged archaeological wood undergoes decay processes that depend on both the burial conditions and the constituting species, and which cause the depletion of the structural components of wood cells. To quantitatively assess the state of preservation of the decayed material, specific parameters are usually measured by means of both chemical and physical analyses. In this paper an innovative approach in the use of the data obtained from these kinds of measurements is developed. A series of 132 archaeological wood samples of different wood species, burial times and states of preservation, and coming from different sites in Italy, was analysed. Their residual chemical composition, maximum water content and basic density were measured, and a reasoned use of these parameters was carried out through their elaboration, with the aim of both evaluating eventual incongruence or anomalies in the raw physical and chemical data (which has never been accomplished so far) and directly comparing in a reliable way the analytical results obtained from archaeological samples with very different states of preservation. This approach allowed defining the effective values of chemical parameters related to wood decay according to a same reference basis of calculation among the various data. By this way, it was possible to state that lignin can be also attacked by the agents causing biotic decay, and that in hardwoods its decay is more related to the burial conditions than to the wood species. Instead, the mechanism of polysaccharide depletion is diversified: conifers showed a uniform behaviour whereas hardwoods were more species-dependent. Moreover, in addition to the chemical composition, also anatomical factors influence the carbohydrate rate of decay in waterlogged wood.  相似文献   
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