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21.
ABSTRACT This paper considers a location model to illustrate the effect of zoning on competition. A planner is in charge of designing a city in a circular space where firms and consumers are located on different sides. With this type of market configuration, equilibrium in location under concave transport costs is proved. Then, a welfare function with different weights attached to consumer and firm surpluses is introduced to highlight zoning regulation as an influential competition policy tool. Depending on the regulator's political profiles and the demand, it is shown that zoning can lead to strong, weak, or moderate competition.  相似文献   
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This article provides a comprehensive assessment of the effects of social protection interventions on material and subjective elements of well‐being. Drawing on a longitudinal survey located in two relatively deprived parts of Brazil, it assesses the effects of pensions and other cash transfers on the well‐being of older people and their households. This analysis is located within a dynamic economic and public policy context. The article finds that pension benefits significantly increase per capita income and that this is strongly associated with overall levels of satisfaction with household well‐being. Levels of reported subjective well‐being do not fall as respondents age, and the survey finds high levels of optimism about future well‐being. The positive effects of pension benefits were supported by upgraded health services and by more specific policies such as access to credit on favourable terms. Overall, the authors conclude that a combination of economic growth and effective public policies significantly boosted the well‐being of most households in their survey, and that Brazil can be taken as a model of good practice for other middle‐income countries.  相似文献   
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SUMMARY: In 2014, during construction work at the ex-Civil Hospital in Gibraltar, excavations led by the Gibraltar Museum revealed a major, previously unknown burial ground containing more than 200 skeletons. We present the historical, archaeological and radiometric dating evidence from the site alongside the results of initial osteological analyses. The data indicate that the burials pertain to an earlier 16th-century Spanish hospice, and therefore stand to offer new insights into the functioning of this early modern hospital and the health and movements of people at a time of incipient globalization.  相似文献   
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A review of archaeobotanical data, together with new, still unpublished data, from Roman sites in conventus Bracaraugustanus suggests the Romanization of the northwest Iberia brought little changes to the agricultural strategies of local communities in indigenous-type settlements. The main crops remain the same as in the Iron Age: Triticum aestivum/durum, Panicum miliaceum, Hordeum vulgare subsp. vulgare, Triticum turgidum subsp. dicoccum and T. aestivum subsp. spelta, Avena and Vicia faba. The first secure reference for the cultivation of Secale cereale in the region comes from a Roman context, suggesting that it was introduced in this period, although it probably remained a minor crop.  相似文献   
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The rock art in Altamira Cave was the first ensemble of Palaeolithic parietal art to be identified scientifically (Sautuola, 1880). Due to the great thematic, technical and stylistic variety of the art in the cave, which constitutes one of the most complete Palaeolithic art ensembles, Altamira was listed as World Heritage by UNESCO in 1985. Uranium-series dating has recently been applied to figures on the decorated ceiling in the cave. Several motifs are partly covered by thin layers of calcite precipitates, whose formation process is datable by this method. The results provide the date when the calcite formed, which gives a minimum age for the underlying depictions. These results confirm that the parietal art at Altamira was produced during a prolonged period of time, at least 20,000 years (between 35,000 and 15,200 years ago), and that part of the ensemble corresponds to the Aurignacian period.  相似文献   
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Marsola, J.C.A., Grellet-Tinner, G., Montefeltro, F.C., Sayão, J.M., Hsiou, A.S. & Langer, M.C., 2014. The first fossil avian egg from Brazil. Alcheringa 38, 563–567. ISSN 0311-5518.

In contrast to the rich record of eggs from non-avian dinosaurs, complete eggs attributable to Mesozoic birds are relatively scarce. Nevertheless, several well-preserved specimens have been discovered over the last three decades revealing functional and phylogenetic characters that shed light on the breeding strategies of extinct birds. Here we report the first fossil avian egg from Brazil, which was discovered in Upper Cretaceous strata of São Paulo in the southeastern part of the country. The taxonomic identity and structural features of the biomineralized tissues were determined using a combination of Scanning Electron Microscopy, Wave Dispersion Energy analyses and Computed Tomography. These show that the 125.5-μm-thick shell of the 31.4?×?19.5?mm egg incorporates three structural layers of similar thickness with both prismatic and aprismatic boundaries. Close similarity between the Brazilian bird egg and those of enantiornithines from the Upper Cretaceous Bajo de la Carpa Formation (Río Colorado Subgroup) of Argentina advocates affinity with basal Ornithothoraces. Furthermore, coherency of their depositional contexts might imply a compatible preference for breeding and nesting environments.

Júlio Cesar de A. Marsola [], Annie Schmaltz Hsiou [] and Max C. Langer [], Laboratório de Paleontologia de Ribeirão Preto, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes 3900, Ribeirão Preto, São Paulo state, 14040-901, Brazil. Gerald Grellet-Tinner [], Centro Regional de Investigaciones La Rioja—Consejo Nacional de Investigaciones Científicas y Técnicas, Entre Ríos y Mendoza s/n, 5301 Anillaco, Argentina; Orcas Island Museum, PO Box 134, 181 North Beach Road, Eastsound, WA 98245. Felipe C. Montefeltro [], Departamento de Zoologia, Universidade Estadual Paulista, Avenida 24A 1515, Rio Claro, São Paulo State, 13506-900, Brazil. Juliana M. Sayão [], Laboratório de Diversidade do Nordeste, Núcleo de Biologia, Centro Acadêmico de Vitória, Universidade Federal de Pernambuco, Rua do Alto do Reservatório s/n, Bela Vista, Vitória de Santo Antão, Pernambuco state, 52050-480, Brazil. Received 18.12.2013; revised 30.4.2014; accepted 18.5.2014.  相似文献   
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During the Upper Paleolithic, lithic variability is one of the most important keys to recognize hunter-gatherer behavior, technology, ecology, and social dynamics. The origin and expansion of Gravettian populations in Eurasia has been seen as one of the most critical episodes in human evolution, argued to be the first clear evidence of the so-called polymorphism among modern human populations. In the case of southern Iberian Peninsula, recent data have shown a new regional and diachronic organization for the Gravettian occupation in this region. Therefore, the interpretation of such variability is one of the most important questions, and functional analysis is a fundamental proxy to recognize human technological, settlement and ecological adaptations as major factors for this polymorphism. This study focused on lithic use-wear analysis of the Early Gravettian of Vale Boi (southern Portugal), in order to understand lithic technological organization and variability within and between occupations at the site. Results show similar patterns between assemblages, showing that different materials were worked at the site, although showing reduced time of work, low variability and percentage of pieces used. Unlike other Gravettian contexts in southern Iberia, the Early Gravettian from Vale Boi is characterized by some variability of backed points, marked by the predominance of bipointed double-backed bladelets. Functional analysis of the Early Gravettian lithic industries of Vale Boi provide a new insight to interpret human technology and settlement strategy during the onset of Upper Paleolithic industries in western Eurasia.  相似文献   
30.
Portugal dos Pequenitos (literally, ‘Portugal for the Little Ones’), a theme park built in Portugal as part of the Centenarian Commemorations of the Portuguese Nation of 1940, has been considered one of the most controversial pieces of Portuguese architecture in the 20th century. Designed between 1937 and 1962 by Architect Cassiano Branco, at the initiative of Bissaya Barreto, it features reproductions of uniquely typical Portuguese architecture built to a child's scale. It includes buildings from mainland Portugal, from the Azores and Madeira islands and from the colonial territories in Africa and Asia. The main aims of this paper are twofold: firstly, to frame Cassiano Branco's architecture in its specific context, in terms of historical contingencies and architectural controversies during the Estado Novo (New State) Portuguese dictatorship (1933–1974), and secondly, to assess the importance of Portugal dos Pequenitos as a laboratory for rehearsing an idyllic urban environment, applying hypothetical principles of national identity.  相似文献   
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