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We have investigated the survival of PCR-amplifiable mitochondrial and nuclear DNA in a small number of modern and medieval bovine leather samples. The results of this preliminary investigation demonstrate that, while no nuclear DNA can be PCR-amplified from any of the specimens, mitochondrial DNA can be amplified from all samples. To investigate this contrasting pattern of DNA survival further, we have vegetable-tanned cow skin in our own laboratory, and directly assayed the survival of PCR-amplifiable mitochondrial and nuclear DNA at each step of the process. The results indicate that nuclear DNA is reduced to sub-amplifiable levels as a result of the tanning baths, whereas amplifiable mitochondrial DNA survives the complete process. Our results suggest that old and archaeological bovine leather may represent a useful source of genetic information, although this information will most likely be limited to that which can be gained from mitochondrial DNA.  相似文献   
63.
It is important to determine the geological sources of Palaeolithic ambers in the south of Europe in order to understand the mobility and interchanges of prehistoric societies. Fourier transform infrared (FTIR) spectroscopy analysis carried out on Upper Palaeolithic ambers from La Garma A cave (Cantabria, Northern Spain) allowed us to identify their source area. Their diagnostic features were found to be similar to the amber obtained in the Lower Cretaceous outcrops close to this archaeological site, and to differ clearly from Baltic amber, which has been generally suggested as the amber found in European prehistoric sites. These results show that the origin of the Gravettian amber found in La Garma A is local and, consequently, a hypothetical contact route is not required to be able to account for the presence of this material in the Iberian Palaeolithic context studied here. For the first time it has been demonstrated that the provenance of an archaeological amber in the Iberian Peninsula is local, with both geographical and spectroscopical evidences. Our study also concludes that the archaeological amber of La Garma A possibly belongs to an araucariacean resin that originated from the coniferous forests which grew in the northeast portion of the Iberian Plate c.110-million years ago.  相似文献   
64.
This work analyses the main Spanish legislative and urban planning instruments, highlighting some of the most important structural problems of the current Spanish urban realities. The survey on legislation runs from the first Land Use Act of 1956 to the decentralization of the administration and the culmination of the transfer processes to the respective Spanish regions. Later, we study the complete well-structured hierarchy of urban planning instruments in use at present. Finally, we analyse how these and other factors have an influence on the capacity to control housing prices and on a lack of sustainability characterized by the excessive urbanizing use of the land.  相似文献   
65.
The Qhapaq-Ñan Project promotes the integration of shared cultural values among six countries: Argentina, Chile, Bolivia, Peru, Ecuador and Colombia. These countries are collaborating to nominate the Main Andean Road or “Qhapaq-Ñan” for inclusion on UNESCO’s World Heritage List. Although the participants envision local and Indian communities as the true beneficiaries of the project, and the archaeological effort is already under way, communities associated with the road have not been involved. (At the very moment we are editing this article (March 2007) Argentina is holding the first meeting about a project that is already five years old, with some of the Indian communities of the territories where the project will be carried out. The participation, however, was far below what we expected.). Following the guidelines of the World Archaeological Congress and the current emphasis of many heritage professionals on community participation, we strongly advise that these dynamics must be changed and that the program must be developed jointly with affected communities from the beginning of the project and not in subsequent steps, or (even worse) once the project already taken shape.  相似文献   
66.
During colonial times, an active maritime trade existed between Spain and the New World, with convoys sailing annually to and from Mexico and returning via Havana, Cuba, after wintering in America. A database constructed from secondary and open sources revealed that Spanish vessels were sailing over open waters along a northern path near Louisiana and a southern path across the central Gulf of Mexico. These routes were traversed in about one month and scheduling for the convoy was based on an understanding of the Americas’ meteorological and oceanographic climate. However, other factors may also have been involved in the directional layout of the routes. Today these ancient routes crisscross planning areas for oil and gas lease sales in the US Exclusive Economic Zone and the information presented in this article may aid in identifying areas where historic shipwrecks may lie. Maps and documents found during this study helped piece together the evolution of our understanding of the Gulf of Mexico surface circulation and how this knowledge influenced sailing during colonial times.  相似文献   
67.
Micromammalian bone assemblages from modern pellets of the strigiform Bubo virginianus magellanicus, from the upper Atuel River (southern Mendoza, Argentina), were taphonomically analysed. The results allow us to place B. v. magellanicus in the category of intermediate modification (Category 2). This sample has also been compared with results from other members of this genus, in order to classify B. v. magellanicus as a taphonomic agent. The participation of the Bubo species in archaeological accumulations has been documented, but in Argentina, the role of B. v. magellanicus has been reported up to the present. It is partly because of the sequence of one archaeological site in the south of Mendoza Province called Laguna El Sosneado‐3 (LS‐3). However, considering the absence of a current taphonomic model of this owl, this participation was mentioned as a hypothesis. In the current investigation, archaeological and modern samples have been compared. The results indicate that the skeletal element assemblages recovered from LS‐3 were accumulated by strigiform birds. Taphonomical evidence of light modifications on units I and IV indicates that Tyto alba (Category 1) was probably the main species involved in these units, whereas the taphonomical evidence on skeletal element assemblages recovered from units II and III suggests the action of a strigiform with a major category of modification such as B. v. magellanicus. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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The recording and 3D modelling of complex archaeological sites is usually associated with high capital and logistical costs, because the data acquisition must be performed by specialists using expensive surveying sensors (i.e., terrestrial laser scanners, robotic total stations and/or ground‐penetrating radar). This paper presents a novel, low‐cost, user‐friendly photogrammetric tool for generating high‐resolution and scaled 3D models of complex sites. The results obtained with unmanned aerial vehicle (UAV) photogrammetry of an archaeological site indicate that this approach is semi‐automatic, inexpensive and effective, and that it guarantees quality.  相似文献   
70.
In this work, we present the results of the characterization of 20 lime plaster samples taken from the Sacred Precinct of Tenochtitlan (Mexico City), the ancient capital of the Aztec empire. The samples come from different buildings of this precinct (A, B and D) and from the west façade of phase VI of the Templo Mayor pyramid. The objective of the work is to characterize the plaster samples, to understand the raw materials used, and to evaluate the presence of similarities and differences among the samples in the building techniques and raw materials employed. All the samples were studied with OM, SEM–EDS and LA–ICP–MS. The study provided evidence of the plastering and replastering practice in the same constructive phases. The results of the analyses showed the existence of important similarities and differences among buildings and constructive phases in the Sacred Precinct. In order to understand the provenance of the limestone used in the plasters, the lumps and the binder of the samples were analysed. The results were compared with those of the limestone outcrops located in central Mexico. The provenance study showed that all the limestone used in the construction of the analysed buildings of Tenochtitlan's Sacred Precinct comes from the Tula region.  相似文献   
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