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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   
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Non-urbanized areas (NUAs) play an important role in reducing the effects of climate change by providing both carbon storage and sequestration. Urban areas are responsible for the emission of 60% of global greenhouse gas, 50% of which are produced by buildings. During the past decades, increasing urban growth and sprawl processes produced several urban layouts characterized by different morphological features and a common lack of sustainable energy and environmental solutions. Investigating the relationship between urban morphology, energy demand and carbon emission/sequestration represents a relevant topic for urban planning practices implemented to face urban climate change effects. This study proposes a method for a transformability assessment aimed at investigating the transformation suitability of different urban morphology types. The case study is the metropolitan area of Catania (Italy), characterized by an impressive urban growth since the 1960s. The proposed method identification of limits and options for increasing sustainability of urban areas considering the contribution of both NUAs and built-up areas. This approach allows to identify appropriate planning tools for new layouts of urban fabrics while increasing the objectivity of the decision process. In the framework of climate change mitigation and adaptation, the outcomes of this research may lead to innovative urban planning practices.  相似文献   
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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   
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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   
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We examine the relationship between individual commuting behavior and household responsibilities, with a focus on gender differences in that relationship. Using the Dutch Time Use Survey for the years 2000 and 2005, we analyze the relationship between commuting time, home production, and childcare. To deal with reverse causality, we use Propenstity Score Matching techniques to obtain imputed data for individuals. We find that the effect of home production on commuting time for women is more than double that for men, while childcare time has an effect on women's commuting behavior only. Our results shedding light on the Household Responsibility Hypothesis.  相似文献   
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Teaching of critical spatial thinking in higher education empowers graduates to effectively engage with spatial data. Geographic information systems (GIS) and science are taught to undergraduates across many disciplines; we evaluate how this contributes to critical spatial thinking. The discipline of GIS covers the whole process of spatial decision-making, but GIS modules often ignore the context setting of spatial problems, and just cover the technical aspects of how to use GIS software. We outline how some existing GIS practicals could be improved to focus on the development of critical spatial thinking skills, competences and abilities that are valuable to graduates.  相似文献   
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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   
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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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