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1.
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   
2.
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   
3.
Research projects undertaken in the Cantabrian region since 1980 have produced new, high-quality information about the neolithisation process(es) in this area. It is now necessary to review this archaeological information and test the main hypotheses put forward to explain it. This paper presents an update on the archaeological evidence (sites, chronological dates, archaeozoological, archaeobotanical and technological information) for the early Neolithic in the Cantabrian region. It summarizes recent research on neolithisation in the region, and assesses the impact of this process during the early Neolithic, and its later consolidation. Although the available information is still incomplete, it is now possible to identify the focal point of the introduction of elements characteristic of the Neolithic way of life in the region. Current evidence suggests that it is in the eastern sector, where the earliest arrival of domesticates and new technologies such as pottery has been attested. The existence of continuities—such as sustained reliance on hunting and gathering and the coexistence of old and new funerary rites—suggests the persistence of native populations, which gradually participated in the neolithisation process after an ‘availability phase’.  相似文献   
4.
It is proposed that there is an iconographic and epistemological relationship between some drawings in Felipe Guaman Poma de Ayala’s Nueva corónica y buen gobierno and the images recorded in several colonial wood vessels (qeros) which circulated widely during the time that Guaman Poma was writing his letter to the King of Spain. This connection shows that the work of Guaman Poma was not an isolated or singular act in the colonial context and that both communicative and creative processes, that of the Nueva corónica and that of the qeros, formed part of a process of shared colonial semiosis through which Andean societies maintained a certain autonomy in the production and circulation of their own discourses. Secondly, the article discusses the epistemological tension that results from the coexistence of different narratives (European and Andean) that used their own temporal and spatial categories to account for new colonial conditions.  相似文献   
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Several traces of biological interaction were found on penguin bones from the basal levels (Aquitanian) of the Miocene Gaiman Formation in the lower Chubut valley of the Provincia del Chubut, Argentina. The fossil-bearing beds were deposited in littoral to sublittoral environments within sediments of mostly pyroclastic origin. We interpret many traces to have been produced by predators and/or scavengers while the penguins were still in a breeding area. Many bones show cracking marks due to aerial exposure. The material is disarticulated as is usual in recent breeding areas. Potential predators were coeval terrestrial mammals, most probably marsupial carnivores. After a marine transgression, these bones were buried or exposed on the sea bottom where they could be colonized by algae, sponges, cnidarians, and other benthic organisms. We identified sponge borings in several bones. Other traces are interpreted to have been produced by echinoderms feeding on sponges or algae. No evidence of other invertebrate predators such as muricid or naticid gastropods, or decapods was found. Finally, other traces appear to have been generated by shark and possibly teleostean vertebrates feeding on epibionts. One coracoid is interpreted to have been marked by a shark that is common in the Gaiman Formation, the carcharhiniform Galeocerdo aduncus. From an ethological (Seilacherian) classification, traces on bones from the Gaiman Formation include Domichnia (sponge perforations), Praedichnia (terrestrial marsupials, sharks, teleosteans) and Pasichnia (echinoderms). Remarkably, remains of marine organisms with skeletons made of calcium carbonate are very poorly preserved in the Gaiman Formation. Only large oysters, sparse shell fragments, skeletal moulds, and bioturbation is evident. The fossil assemblage is mainly composed of phosphatic (e.g. teeth, bones, crustacean parts) and siliceous (sponge spicules, diatoms) remains.  相似文献   
8.
The aim of this article is to focus on the technology of archeological plasters at Teotihuacan (Central Mexico), from the Classic Period (200–650 A.D.), focusing in the study of Teopancazco, a neighborhood center in the city. Petrographic and chemical analyses by OM, SEM-EDS, and LA-ICP-MS were conducted to characterize samples from different constructive phases and sectors of the neighborhood center, to determine the provenance of the raw materials employed in the manufacturing (e.g., volcanic glass shards) and to assess whether a shift occurred in the manufacturing of plasters and in the procurement strategies of raw materials during the different phases. The results of the analyses show that almost no changes occurred in the making of the plaster during more than four centuries and allow us to consider the presence of a technological style in their manufacture, which is characterized by the making of plaster by mixing lime with volcanic glass shards, which in the case of Teopancazco were derived from the Altotonga (Veracruz) magmatic system. The data at our disposal suggest that this style was developed in Teopancazco and later introduced throughout the city of Teotihuacan in the Early Xolalpan phase (A.D. 350), although we still do not know whether the provenance of the raw materials is the same. The wide distribution of this technological tradition could be due to the technological properties of the materials and/or the influence of the intermediate elite who ruled over Teopancazco. The paper confirms that the study of material culture and technology sheds light on broader cultural aspects of ancient societies.  相似文献   
9.
Classical industrial districts' literature is not focused on the role played by external ties but gives more importance to the local districts' endogenous development. Global value chains connect clusters to other external agents through external linkages and constitute a framework to analyse the complex inter-linkages between clusters and other external agents. In the field of the external ties and the global value chain approach Academia is primarily focused on the ties which link clusters in developing nations to global markets, although global value chains also consider connections between clusters in similar activities and even when both are located in developed nations. Thus, external linkages are mainly performed by multinational enterprise (MNE) affiliates which play fundamental role of knowledge diffusers and absorbers in the process of knowledge exchange throughout global value chains. The work examines the process of knowledge exchange between clusters through external ties using the global value chain approach. For this purpose, empirical work is conducted with 22 face-to-face interviews to provide a case study about a leading cluster in the global ceramic tile industry. Results show that the basic knowledge to successfully compete is locally originated, although it can be complemented with global knowledge learnt or generated in other territories. MNE affiliates bridge structural holes through external ties and reduce knowledge asymmetries within global value chains. External ties on network-based governance chains exist, matter and affect clusters allowing upgrading even between developed nations.  相似文献   
10.
Jacobean devotion and national awareness are closely related in the Poema de Fernán González (PFG). The great advance of the Reconquest in the thirteenth century and the reevaluation of the past that it caused enabled the broad Hispanic perspective of the PFG. Spain is not only a distant and longed-for reality (“regnum Gothorum”) but a current political concept. This is the frame of the PFG's intense Castilian sentiment. Castile is the bastion of the Visigothic monarchy, which did not yield to the Muslims and was the foundation for the recovery of Spain. The territorial diversity becomes the outstanding feature of this country, in which the “Montaña” takes an important role. Confronting the proposal of the cult of Saint Millán by the Monastery of San Millán de la Cogolla, the author of the PFG, aware of the damages that such a cult was causing to his monastery, clings to the Jacobean devotion that achieved a broad Hispanic scope.  相似文献   
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