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1.
The chemical and mineralogical characterization of seven ceramic fragments produced within Tiwanaku state (c.500–1000 ce ) is reported. The instrumental techniques used included X‐ray elemental and mineralogical chemical analysis, Raman spectroscopy, and scanning and light microscopy. The results indicate there are several clay types, although they show similarities, such as the use of a plant‐based temper. The red colour of the decoration is hematite, and manganese oxides such as jacobsite are present in the black. The white colour is a mixture of gypsum and clay, and the orange is a mixture of hematite and clay. The use of colours, the quality of the clays and the temperatures reached during pottery firing point to expertise in ceramic production and to complex decision‐making processes. The multi‐elemental archaeometric approach documented here could become an important tool to shed a light on ancient ceramic technology and the internal variance of Tiwanaku pottery.  相似文献   
2.
The standard theory of optimal jurisdictional size hinges on the existence of economies of scale in the provision of local public goods and services. However, despite its relevance for forced local amalgamation programs and related policies, the empirical evidence on the existence of such economies of scale remains elusive. The main goal of this paper is to produce an updated and comprehensive quantitative review of the existence of economies of scale in the provision of local public goods using a meta-analysis approach to systematize the wide range of empirical approaches and modeling frameworks found in the previous literature. Our analysis confirms the presence of moderately increasing to constant returns to scale in the provision of local services with no reduction in the average costs of production in the delivery of most local public services beyond a certain, modest jurisdictional size, which many studies have estimated at 10,000 residents. Also, the potential for economies of scale differs at least across three traditional services: education, water and sanitation, and garbage collection, being highest for education and lowest for garbage collection. Our analysis also offers guidelines for future empirical research in this area. Physical output and production cost data should be used, together with translog specifications for the modeling of cost functions. Last, we find evidence that the determinants of output cost elasticity include bidirectional publication bias and population density but do not include the presence or absence of modern “lean” production technologies or the (perceived) capital intensity of the sector, contrary to conventional wisdom. These findings have significant policy implications for countries considering jurisdictional consolidation programs.  相似文献   
3.
The restoration of paintings on elements in cultural heritage buildings (fundamentally, churches) involves two structural problems: capturing the geometry of the construction element and its development. In many cases, the geometries are regular (e.g., cylinders, spheres, elliptical domes). However, there are cases in which the elements cannot be adapted to any known geometry, much less one that can be mathematically developed. The development of surfaces becomes essential for the restoration of paintings over “flat elements” (over which work is performed on the ground) that are subsequently transferred to the real surface (ceilings). The mathematical transformations that allow regular geometries to be developed are widely known (cartographic projections). However, when the geometry is irregular, there is no development. This study presents a new methodology based on differential rectification and its application for the development of oculi in the Los Santos Juanes Church (Valencia), whose geometry is completely irregular both in shape and as a result of construction defects (and damage caused by fire). The present study focuses on the restoration of paintings damaged by fire.  相似文献   
4.
ABSTRACT

This paper contributes to the study of the role of public policies in the origins and evolution of clusters. Building on the existing literature, we set up a taxonomy of nine public policies that may have an impact on the emergence and evolution of clusters. Based on in-depth case studies of six clusters of the Basque Country, particularly representative of the industrial history of the region, we analyse the relevance of the different types of policies both in the emergence and evolution of clusters over time. In agreement with cluster literature, the paper concludes that public policies seem to have played only an indirect role across clusters and over their life cycles. Moreover, it points to the necessity of taking history and context into account, as most of the important policy measures highlighted by cluster literature today do not fit well with the previous policy and economic context. Finally, it also concludes that for cluster policies to be effective, the stages of the life cycle should be taken into consideration.  相似文献   
5.
This paper follows the form of that by Mazzarello that precedes it (Mazzarello, 2006) and presents an imaginary interview with Santiago Ramón y Cajal in December 1906. A few days earlier Cajal had been awarded the Nobel Prize for Physiology or Medicine, an award that he shared equally with Professor Camillo Golgi. Golgi had been recognized for his work as a pioneer into investigations of the nervous system, primarily on account of his discovery of the "black reaction" of silver chromate impregnation of whole nerve cells and their processes. Cajal had been recognized for his implementation of that method and for laying with it the foundations of what was to become modern neuroanatomical science. Paradoxically, the two awardees had been led by their researches to diametrically opposed views of the organization of the nervous system. Golgi believed in a continuous network of axons that formed the basis of all the integrative properties of the nervous system, while Cajal had provided the information that led to the formulation of the neuron doctrine that saw the nervous system as being made up of chains of discontinuous cells joined by polarized functional contacts that we now call synapses. The paper takes the form of an interview with Professor Cajal in the Grand Hotel Stockholm. His responses to questions posed by the imaginary interviewer are all taken from Cajal's own writings.  相似文献   
6.
This paper is an attempt to analyse taxation from a wide-ranging social perspective. Earlier studies of this topic have focused on institutional aspects of taxation and produced statistical information of great value. The historian who is trying to understand the social structures of the past should, however, examine the significance, nature and function of taxation in its wider historical context. In this sense, and in the specific case of post-Roman, or Visigothic, Spain, a study of the social aspects of taxation reveals new meanings of the term 'politics', showing it to involve far more than a single inflexible concept independent of social factors. On the one hand, one should not equate taxation with fiscality, because the latter is one part (that concerning the fiscus or royal patrimony) of the wider whole comprised by the former: the capacity of the regnum to yield tribute, which is in turn related to revenue extracted by the aristocracy. It was the fiscal dimension of taxation that allowed the Visigothic kingdom to survive in Spain for two centuries. On the other hand, the centre, occupied by different sectors of the potentes , negotiated with other groups of these same potentes . These negotiations underlay military support for the centre, as well as provoking crises and mistrust when they were bypassed. Taxation was an integral part of such negotiations.  相似文献   
7.
In this paper, based on the case study of the aerospace cluster of the Basque Country (Spain), we aimed at analysing how local industries develop a new specialization, that is, how a cluster emerges, and how it evolves over time. For that purpose, apart from considering local factors (both forces that are internal to the cluster and to the territory), we explicitly consider the role of institutional and technological changes, and how they affect industry structure and governance patterns of global value chains (GVCs). We observe that global-scale regulations (deregulation and competition policy) and technological change, together with local factors such as the existence of anchor firms, local policies, related variety and social capital at regional and cluster levels played a significant role in the emergence of the cluster and how it became inserted in the GVCs. Later on, the development of suppliers' capabilities also had a relevant role in the evolution of the governance patterns of GVCs.  相似文献   
8.
This article offers a microhistorical approach to the shaping of regional cultures during the nineteenth and twentieth centuries to show that this process was not only imposed from centres of nationalisation as a complement of national identity, but that it also had to be negotiated with elites in provinces at the periphery. Specifically, the article looks at how the regional songbook of Majorca took shape between 1837 and 1936. In this process of musical regionalisation, the cultural authority of the tourism and colonial discourse about the island was strategically exploited by local musicians to gain some share of power from below in negotiating their own regional identity with nationalising institutions. In this way, the Spanish and Catalan national identities being projected over the island were ultimately decentred and transformed.  相似文献   
9.
This paper investigates the critical role of workers to enhance the resilience of water supply services in cities at war through analyzing the case of Madrid and the Madrid water company Canales del Lozoya during the Spanish Civil War (1936–1939). We argue that securing the protection of vital urban flows mediated through infrastructures is a key objective of cities under attack. In doing so we contend that examining how those affected by the interruption of these flows cope with the situation represents a valuable but largely neglected form of water management. We illustrate how quotidian knowledge about the urban geography of water flows may have important repercussions for the war effort itself. In a nutshell, the case of Madrid offers an early account of the critical role of water workers in sustaining “urban ecologies under fire” securing the complex urban metabolism while also contributing to the struggle against invading forces.  相似文献   
10.
Vultures are ubiquitous taphonomic agents in most biomes. However, taphonomic studies of vultures are scarce and very little is known of the damage they cause to bone surfaces when consuming carcasses. This study presents the results of a taphonomic analysis of bones modified by griffon vultures. Although some marks created by these agents are diagnostically unique, others are extremely similar to modifications caused by other biostratinomic processes. This renders interpretations of marks on bones very problematic when these modifications are considered in isolation rather than at the assemblage and contextual levels.  相似文献   
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