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The preservation process of soft tissues in an archeological context is mainly unknown because they occur only in truly exceptional situations. The Cova des Pas is a Bronze Age site in Minorca where the special conditions enabled the preservation of some soft tissues associated with 66 individuals. This finding allows the study of the preservation process that took place by means of the analysis of the histological and chemical characteristics of the tissues. Our results show that the preservation mechanism was the adipocere, because the fatty acids profile shows higher concentration of saturated than unsaturated fatty acids. The evidence indicates that the kind of funerary ritual and the environmental conditions favored this preservation.  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   
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Archaeological data reveal two distinctive cultural adaptations on the Pampa and Patagonia of Argentina: terrestrial hunter-gatherers in the former and most of the latter region and maritime hunter-gatherers along the southern extreme. Both adaptations were achieved by the end of the fifth millennium B.C. Thereafter, a stable equilibrium was maintained, with a slow drift toward greater emphasis on resources providing the maximum return for the least effort. The high productivity of the Fuegian environment sustained a population 30 times greater than occupied the Pampa and continental Patagonia prior to Araucanian penetration in the sixteenth century A.D. The long-term stability is attributable to the absence of environmental or demographic pressures or encroachments by neighboring groups, which might have made more intensive exploitation of the environment necessary.  相似文献   
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Landscape interpretation is needed for navigating and determining an orientation: with traditional cartography, interpreting 3D topographic information from 2D landform representations to get self-location requires spatial orientation skill. Augmented reality technology allows a new way to interact with 3D landscape representation and thereby facilitate the orientation of oneself in respect to the environment to determine goal location. This paper analyses if AR spatial landform improves the learner’s spatial orientation skill measured with the perspective taking/spatial orientation test by paired sampled t-tests. A workshop was conducted with 123 university students (63 treatment group, 60 control group) in which students had to identify locations and routes based on the interpretation of the relief, represented by AR. Results of the workshop showed an improvement in spatial orientation skill of 20.14 degrees average gain in the treatment group. Students who were not subject to the workshop (control group) did not improve their spatial orientation skill. The possibility of using free AR three-dimensional applications and exploit the potential of tablets and smart phones, which are widespread today, makes it possible to design and implement strategies for the development of spatial skills in formal teaching in the scope of Geography in higher education.  相似文献   
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The present work aims at elucidating the technology applied in the fabrication of ceramic objects by the ancient ceramists that inhabited the western border of Pantanal, Mato-Grosso do Sul, with the help of a multidisciplinary approach making use of chemical and physical methods of analysis. The potshards under study show the presence of different types of additives, as determined by scanning electron microscopy (SEM) and time of flight secondary ion mass spectrometry (ToF-SIMS). The dispersion of the additives within the ceramic matrix was also addressed by SEM, which shed light on the mounting technique used by the potters to assemble the ceramic vessels. Moreover, the tensile strength conferred to the pottery by the use of a specific type of additive was evaluated by applying a mechanical test. These results were correlated with the firing temperature of the potshards, determined by means of electron paramagnetic resonance (EPR).  相似文献   
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This study concerns the moral regulation of the Person in Brazil from the twenties to the end of the forties, from the point of view of the intense academic relationship between anthropology and psychoanalysis. It deals with the conditions under which that dialogue took place: the general crusade for the «civilization» of the country, between the central State initiatives in the promotion of hygiene and education and the medical, intellectual debates about the «African» heritage and the possibility of surmounting cultural «backwardness».  相似文献   
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According to the theory of conventions, food value chains (FVCs) involve a complex array of actors who share an agreement about the qualities embodied in their particular foodstuff. Nevertheless, that agreement is continuously challenged by changes in consumer markets. Therefore, I argue that FVCs able to adapt those qualities to new trends will perform better than FVCs whose commitment to certain qualities leads to a misunderstanding between producers and consumers. The organization of the chain itself, the values of national regulatory frameworks, and the goals of the national innovation system are discussed as factors that shape an FVCs' ability to re‐arrange that core agreement. By using professional reports, statistical records and personal interviews, this article focuses on two FVCs that have experienced contrasting trajectories in recent decades in the Spanish market: the wine industry located in the region of Castile and Leon (Spain) and the Norwegian salted cod industry. The growing wine FVC has achieved a successful agreement about a set of qualities linked to nature, tradition, and place, all of them guaranteed by the reputation of the Designation of Origin (DO) system. In contrast, the salted cod FVC is losing its market share because its main actors are failing to properly communicate the key qualities of environmental sustainability and artisanal cod production to concerned Spanish consumers, as well as in the adoption of the place‐related attributes that still shape consumer preferences in Spain.  相似文献   
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