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971.
972.
Traditional taphonomic analyses do not consider the emergent properties resulting from the relationship of variables. Several of these emergent properties are expressed spatially. Here, we present a spatial taphonomic approach to the understanding of post-depositional processes affecting experimental assemblages modified by fluvial currents. Spatial statistical methods are a great tool to understand how different taphonomic variables relate at a spatial scale. The results of the application of this method to bone assemblages affected by low- and high-energy flows show the loss or modification of most of the original spatial taphonomic relationships. It also shows the degree of bone loss according to element, anatomical section and bone structure, and shape types. Anisotropy is identified in both experimental contexts. These results add new criteria to assess the impact of water flows in bone assemblages and contribute to define the properties of lag assemblages.  相似文献   
973.
Preliminary functional results obtained from the quartzite assemblage of the Early Middle Palaeolithic site of Payre (South-eastern France) are presented. In an area rich in flint, hominins at Payre also collected quartzite in their local environment, specifically along the Rhône River banks. Although the Payre lithic assemblage is largely composed of flint, quartzite was introduced in the site mainly as large cutting tools knapped outside. This fact pointed out an apparently highly differential treatment of the raw material types available in the region. A major concern is to understand the reason why. Is there any functional reason for the introduction of those artefacts, perhaps to perform specific activities related to the toughness of quartzite? Or is there any functional differentiation among the various raw materials? Use-wear analysis is a useful tool for better understanding human technological choices and strategies of lithic raw material management. Before attempting to extensively apply use-wear analysis on the quartzite assemblage, we analysed a limited sample to evaluate the general surface preservation. A specific experimental programme with the same local quartzite was carried out in order to provide a reliable comparative reference for interpreting use-wear evidence on archaeological implements. Methodological difficulties related to use-wear analysis applied to quartzite artefacts are also discussed. Both Optical light microscopy (OLM) and Scanning Electron Microscopy (SEM) were employed in this study; however, interpretations were elaborated considering principally SEM micro-graphs.The analysis of the archaeological material showed a good state of preservation of the surfaces with a low incidence of post-depositional alterations. The documented use-wear allowed us to identify the active edges, the kinematics and, more rarely, the worked material. Chopping activities were documented on two large artefacts suggesting a specific utility of those tools.  相似文献   
974.
Pigments appearing on ninth–twelfth-century AD-carved stucco, wall painting, and terracotta friezes excavated at Nishapur in north-eastern Iran were investigated by optical reflectance spectroscopy, micro X-ray fluorescence spectrometry (μ-XRF), X-ray diffractometry (XRD), micro-Raman spectroscopy (μ-Raman), and scanning electron microscopy (SEM). Many of the pigments identified including vermilion, red lead, hematite, limonite, carbon black, atacamite, calcite, and gypsum have been identified in previous studies of pigments used in later Islamic periods. However, a series of unusual pigments such as wulfenite, pyromorphite, phoenicochroite, and jarosite were also found in the present study. The association of kaolinite and alunite with limonite and other Fe-bearing yellow pigments points to a local provenance for these pigments. In addition, the presence of orpiment in the vermilion may be indicative that the vermilion was artificially manufactured. These findings suggest that pigment use and manufacturing during the ninth to eleventh centuries in Nishapur was still in a trial-and-error stage and the palette known from the twelfth century onwards had not yet been systematized.  相似文献   
975.
Compound-specific amino acid carbon-isotope compositions have shown particular promise for elucidating dietary behaviors in complex environmental contexts, and may also be able to mitigate the effect of many of the limitations inherent to palaeodietary reconstructions. Here, we investigate the efficacy of compound-specific amino acid isotopic proxies in characterizing the consumption of different dietary protein sources using amino acid carbon-isotope compositions for humans and fauna from Rössberga (Early to Middle Neolithic), Köpingsvik (Mesolithic and Middle Neolithic), and Visby (Medieval Period), Sweden. We also assess the explanatory capabilities of an isotopic mixing model when used with essential amino acid carbon-isotope compositions of humans and local fauna. All three isotopic proxies distinguished among humans from the three sites consistently and informatively, and were able to enhance the broad interpretations made using bulk isotopic compositions. The mixing model palaeodietary reconstruction revealed considerable diversity in relative protein source contributions among individuals at both Köpingsvik and Visby. Comparing the mixing model for bulk carbon- and nitrogen-isotope compositions to the model for essential amino acid isotopic compositions further demonstrated the likelihood of underestimation and overestimation of marine protein consumption for both aquatic-dominant and mixed marine-terrestrial diets when using bulk isotopic compositions.  相似文献   
976.
The use of seashells for the decoration of pottery from the sixth millennium cal BC is well known in the western Mediterranean, with the emergence of so-called Cardial Pottery. Actually, the most discussed issue up until now has been the use of bivalves for impressed decoration. However, the experimental approach followed in the present study provides for the first time clear evidence for the utilization of a very specific group of shells as tools for the decoration of some of the early pottery productions in northwest Africa. In particular, we propose the use of cowry, a gastropod family with a well-known ideological and symbolic role in many human cultures around the world. Also, it is suggested that cowry was used for making impressed wares on the opposite European shore. The implications for reconstruction of Neolithic diffusion along both the European and African coasts of the Mediterranean are of great significance.  相似文献   
977.
Tineo, D.E., Bona, P., Pérez, L.M., Vergani, G.D., González, G., Poiré, D.G., Gasparini, Z.N. & Legarreta, P., 1.10.2014. Palaeoenvironmental implications of the giant crocodylian Mourasuchus (Alligatoridae, Caimaninae) in the Yecua Formation (late Miocene) of Bolivia. Alcheringa 39, xxx–xxx. ISSN 0311-5518

Outcrops of the Yecua Formation (late Miocene) are exposed for approximately 230 m along the La Angostura section of the Piraí River (50 km southwest of Santa Cruz de la Sierra). These reveal massive (argillic palaeosols) and laminated (quiet-water lacustrine and marsh settings) mudstones interbedded with thin sandstones containing microfossils, molluscs and vertebrate remains. Significantly, the succession hosts a giant crocodylian, Mourasuchus (Alligatoridae, Caimaninae), which is represented by both skull and postcranial fragments found in association with freshwater turtles and fishes. Mourasuchus was distributed widely from the middle Miocene of Colombia to upper Miocene of Venezuela, Brazil and Argentina, suggesting connections between major fluvial systems and an active mechanism for dispersal of South American freshwater vertebrates during the Miocene.

David Eric Tineo [] and Daniel Gustavo Poiré [], CONICET—Centro de Investigaciones Geológicas, Universidad Nacional de La Plata. Calle 1 (644), B1900FWA, La Plata, Argentina; Paula Bona [] and Zulma Gasparini [], CONICET—División Paleontología Vertebrados, Museo de La Plata. Paseo del Bosque s/n, B1900FWA, La Plata, Argentina; Leandro Martín Pérez [] CONICET—División Paleozoología Invertebrados, Museo de La Plata. Paseo del Bosque s/n, B1900FWA, La Plata, Argentina; Gustavo Dardo Vergani []Pluspetrol S.A. Lima (339), C1073AAG, Ciudad Autónoma de Buenos Aires, Argentina; Gloria González Rigas []Pluspetrol Bolivia Corporation SA, Av. Grigotá esq. Las Palmas, Santa Cruz de la Sierra, Bolivia; Pablo Legarreta []—Pluspetrol S.A. Lima (339), C1073AAG, Ciudad Autónoma de Buenos Aires, Argentina.  相似文献   
978.
979.
Summary

Looking beyond the reaction to and the discourses surrounding inventions, it may appear incongruous to link religion with technological innovation, especially considering the underlying religious motivations of the inventive act. Steamship propulsion and the search for an alternative to the paddle wheel in 1840s France implicates three inventors (Frédéric Sauvage, Augustin Normand, Achille de Jouffroy d'Abbans) and three inventions (the continuous propeller, the divided propeller, the flipper apparatus); only Normand's propeller would have a vertiable future. This contest also entails three different types of religious temperaments: a Romantic religiosity, a “bourgeois” or private Catholicism; and a clerical‐legitimist militancy. The question which will be considered here is: were these inventors influenced by the strength of their religious convictions; and if so, how did this affect their scientific reasoning ?  相似文献   
980.
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