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101.
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   
102.
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   
103.
Endogenous growth models are built around the concept of a knowledge stock. This knowledge stock can also be interpreted as a localized stock that operates at the regional level, as is common in the regional innovation systems literature. We use data from the second, third and fourth Community Innovation Surveys (covering 1994–1996, 1998–2000 and 2002–2004) to measure the build-up of knowledge at a very low regional aggregation level (“across streets and hallways”) in the Netherlands. In doing so, we account for regional agglomeration effects. We find that such local knowledge stocks have a small influence on innovation and are far outweighed by firm-specific characteristics.  相似文献   
104.
With the fundamental rescaling of socio-economic relationships, the mega-city region (MCR) has emerged as an important geographical space for governance. At the same time it is highly fragmented institutionally, making it difficult to overcome collective action problems such as providing regional public transport and protecting open spaces. In practice, different arrangements are employed to address these problems, including hierarchical approaches, competitive self-coordination and joint decision-making. Drawing on experiences in five MCRs in Europe and the US, the relative use and success of these approaches was investigated. The analysis suggests that the composition of the actor constellation (e.g. the number and kind of parties involved) and local political support proved to be important factors in explaining the performance of a particular governance approach. In addition, the findings provide a new appreciation for the role of the state, particularly the national government, in governing MCRs.  相似文献   
105.
The World Heritage Site of Bryggen in Bergen, Norway, has experienced significant degradation of archaeological deposits as a consequence of changes in the soil water and groundwater balance after urban redevelopment adjacent to the heritage site. Additionally, groundwater temperatures below the heritage site were found to be significantly higher closer to the redeveloped area. One of the main mitigation measures taken to reduce the degradation of the archaeology has been the construction of a hydrological barrier along the sheet piling that divides the redeveloped area and the historic site. A shallow subsurface infiltration system was designed to achieve groundwater levels and flow conditions that are optimal for the preservation of archaeological remains directly along the sheet pile, while reducing drainage and subsidence also further upstream. Monitoring of groundwater level and temperatures after implementation of the hydrological barrier shows that groundwater levels and flow conditions have improved with respect to optimal preservation conditions, and groundwater temperatures have generally been reduced by up to 2 °C.  相似文献   
106.
The shallow subsurface in historic cities often contains extensive archaeological remains, also known as cultural deposits. Preservation conditions for naturally degradable archaeological remains are strongly dependent on the presence or absence of groundwater. One of the main goals at such heritage sites is to establish a stable hydrological environment. Green infrastructural solutions such as Sustainable Urban Drainage Systems (SUDS) can support preservation of cultural deposits. Several cases show that implementation of SUDS can be cost effective at preservation of cultural deposits. These include Motte of Montferland, City mound of Vlaardingen, Weiwerd in Delfzijl, and the Leidse Rijn area. In all cases, the amount of underground infrastructure is minimised to prevent damaging cultural layers. SUDS have been implemented to preserve cultural heritage. The first monitoring results and evaluation of the processes give valuable lessons learned, transnational knowledge exchange is an important element to bring the experiences across boundaries.  相似文献   
107.
ABSTRACT

Giovanni Freppa (1795–1870), a well-known antiquarian, was instrumental in propelling the Ginori maiolica firm to reinvent the technique of Renaissance lustreware. The so-called ‘Freppa Scandal’ resulted after he sold as authentic Renaissance pieces a number of plates made by Ginori. Freppa was also famous, or rather infamous, for his exploitation of the young sculptor Giovanni Bastianini, whose remarkable neo-Renaissance portrait busts were sometimes sold as authentic Renaissance works. The Louvre purchased for an enormous price a bust believed to be a Renaissance masterpiece; but it was actually executed by Bastianini in 1864 on commission from Freppa, resulting in ‘the Benivieni Affair’. But this article is not primarily intended to expand on Freppa’s transactions in the art world; rather, it highlights his activities in many other spheres, including a failed publishing project with Giacomo Leopardi, among other activities. Freppa was a more complex individual than indicated merely by the two above-mentioned scandals.  相似文献   
108.
There is an increasing awareness of the potentials of nonlinear modeling in regional science. This can be explained partly by the recognition of the limitations of conventional equilibrium models in complex situations, and also by the easy availability and accessibility of sophisticated computational techniques. Among the class of nonlinear models, dynamic variants based on, for example, chaos theory stand out as an interesting approach. However, the operational significance of such approaches is still rather limited and a rigorous statistical-econometric treatment of nonlinear dynamic modeling experiments is lacking. Against this background this paper is concerned with a methodological and empirical analysis of a general misspecification test for spatial regression models that is expected to have power against nonlinearity, spatial dependence, and heteroskedasticity. The paper seeks to break new research ground by linking the classical diagnostic tools developed in spatial econometrics to a misspecification test derived directly from chaos theory—the BDS test, developed by Brock, Dechert, and Scheinkman (1987). A spatial variant of the BDS test is introduced and applied in the context of two examples of spatial process models, one of which is concerned with the spatial distribution of regional investments in The Netherlands, the other with spatial crime patterns in Columbus, Ohio.  相似文献   
109.
武友德 《人文地理》2000,15(3):69-72
西部不发达区域是我国自然资源密集地区,极具开发潜力,其经济成长采取自然资源转换模式具有客观必然性。但是传统的自然资源要素转换模式已严重制约着西部地区经济的持续发展。本通过对西部地区自然资源优势、资源开发中的技术结构和利益分配机制以及资源转换模式等问题的系统思考,提出了提升区域自然资源转换模式的构想。  相似文献   
110.
The argali (Ovis ammon antiqua) assemblages from the Middle Pleistocene site of the Caune de l'Arago (Tautavel, southern France) were studied in terms of zooarchaeology and taphonomy. It is possible to discern palaeobiological information lost during fossilisation, as well as the palaeoethology of the bone collector, by the observation of taphonomic details preserved on the bone assemblages. The observations leave no doubt that both humans and carnivores were involved in the accumulation of argali carcasses in the cave. In some assemblages, the type of bones found in articulation and the gnawing marks observed are characteristic of carnivores. In other levels, the intense fracturing of the major limb bones in relation to their marrow content and mineral density, and butchering marks found on specimens in the earlier levels, are in favour of human accumulation, the modalities of which are discussed. The results suggest that the degree of carnivore activity seems to have been higher in levels M, N and O than in level F. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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