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71.
The study of the DNA of ancient microorganisms in human remains represents one of the newest and most promising branches of molecular archaeoanthropology. Despite the growing number of papers addressing this subject, however, the analysis of ancient bacterial DNA is still a contentious issue. The indigenous microbiota of the gastrointestinal tract of man represents a community characterized by relative constancy in species composition and proportion. As a model system, we studied the preservation of the intestinal microbiota DNA in two naturally freeze-dried human mummies found on the Alps. This kind of mummy is an ideal subject for ancient DNA investigations. The first is a male body historically dated 1918 A.D. while the second is the famous Tyrolean Iceman (3.350–3.100 B.C.). The screening of bacterial 16S rRNA gene libraries from colon samples of the two mummies (49 clones for the 1918 mummy, 119 clones for the Iceman) showed that the characteristic composition of the intestinal microbiota of man (Alpha-, Beta-, Gammaproteobacteria, Bacteroides, Clostridia) is still kept in the library from the recent mummy while the Iceman's library is almost entirely composed by the DNA of clostridia. Comparison of the intestinal data with those from the literature describing the screening of 16S rRNA gene libraries from other parts of the Iceman's body and from permafrost specimens indicates that the changes in library composition may partly be attributed to the proliferation of clostridia inside the corpses, as described in forensic literature, and partly to the differential persistence of the DNA of gram-negative bacteria and endospore-former low-GC gram-positive bacteria. The present results contribute to the issue of the authentication of claims of pathogen DNA identification in archaeological human remains.  相似文献   
72.
The history of Italian Jews from 1861 to 1938 is often viewed as the period in which they totally assimilated into the Italian nation. This article, however, argues that rather than their assimilation it was a period of their integration into Italian society. Various approaches to this question are presented, including a review of the literature, with a view to reconsidering the relationship between Jewish culture and Italian culture, or rather non-Jewish culture. Italian Jewish history is shown not to be separated from, but to be “internal” to Italian social, cultural, and political history—part of the dynamic process of change that occurred during this period not only in Italy but throughout Europe.  相似文献   
73.
A large ceramic vessel was discovered at São Brás (southern Portugal) containing a metallic hoard from the Chalcolithic/Early Bronze Age period. These weapons and tools were characterized by microanalytical techniques as being composed of copper with varying arsenic contents (2.2 ± 1.6 wt%) and minor amounts of lead, bismuth and iron. The collection shows a clear association between daggers and copper with a higher arsenic content, which can be explained by the high status of these silvery alloys. Finally, the compositional distribution of the hoard was compared with the metallurgy of the Bell Beaker and non–Bell Beaker communities inhabiting the south‐western Iberian Peninsula.  相似文献   
74.
A huge monolithic piece corresponding to the first years of the sixteenth century has been discovered in Mexico City. It represents the earth goddess Tlaltecuhtli. The preservation of such a magnificent piece is imperative. Therefore, the surface has to be characterized and the interaction of consolidants with the rock has to be understood.Some of the consolidation methods are impregnation of the mineral with nopal or silicic acid derivatives. In this work we compare the physico-chemical effects of organic and inorganic consolidants. Original and impregnated samples are characterized with a series of original techniques: X-ray diffraction, nuclear magnetic resonance, nitrogen adsorption and small angle X-ray scattering. Fractal dimension, specific surface area and pore size distribution clearly differentiated the samples. The organic materials, nopal gum or slobber, cover the mineral particles with a smooth layer. The KSE solutions react and lead to microporosity.  相似文献   
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The composition and manufacture of Late Bronze Age metallic artefacts from funerary and domestic contexts of southern inland Portugal was studied. The prevailing trend comprises binary bronzes (10.3 ± 2.1 wt% Sn) showing deformed equiaxial grains, annealing twins and slip bands. The alloy composition is somewhat independent of artefact type, while the manufacture seems to rely on artefact function and the skilfulness of the metallurgist. The technological characteristics were linked with archaeological and chronological features, disclosing some artefacts of uncommon composition, such as low‐tin bronze bracelets (4.3–7.1 wt% Sn) associated with ornaments of exotic materials (glass and Egyptian faience beads, and also ostrich egg shell beads). The assemblage testifies to an archaic trade with the Mediterranean region before the establishment of the first Phoenician colonies on the southern Iberian coast.  相似文献   
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Exaeretodon riograndensis Abdala, Barberena, & Dornelles, 2002 Abdala, F., Barberena, M.C. and Dornelles, J.E.F. 2002. A new species of the traversodontid cynodont Exaeretodon from the Santa Maria Formation (Middle/Late Triassic) of Southern Brazil. Journal of Vertebrate Paleontology, 22: 313325. [Taylor & Francis Online], [Web of Science ®] [Google Scholar] is the most abundant traversodontid preserved in the basal Santa Maria 2 Sequence (Hyperodapedon Assemblage Zone), southern Brazil and is closely related to Exaeretodon argentinus Cabrera, 1943 Cabrera, A. 1943. El primer hallazgo de terápsidos en la Argentina. Notas del Museo de La Plata, Paleontología, 8: 317331.  [Google Scholar] from the Ischigualasto Formation, Argentina. Previous anatomical studies of E. riograndensis have focused mainly on cranial material and little is known about the morphology of its lower dentition or postdentary bones. We describe the first fairly complete postdentary series of the mandible of E. riograndensis and provide additional information on its lower dentition. The postdentary bones of E. riograndensis include a complex coronoid, an angular with a delicate reflected lamina and a stout retroarticular process of the articular, contrasting with the morphology reconstructed for Argentinean specimens, which possess a small retroarticular process. Apart from that, the postdentary bones do not differ significantly from those known for E. argentinus, a fact expected due to the great similarity between other skeletal features of these species. Furthermore, the lower postcanines of E. riograndensis have virtually the same structure as those of E. argentinus, with an approximate quadrangular shape in occlusal view. Moreover, the transverse cusp row is placed anteriorly and comprises a lingual and a buccal cusp, and the occlusal basin delimited by the four main cusps is relatively deep. The new material does not add any taxonomically diagnostic features to E. riograndensis. However, the fossils greatly improve our understanding of the anatomy of the Brazilian species.  相似文献   
79.
This essay examines Antonio Muñoz Molina´s use of the Gothic mode and the misterio genre to destabilize Madrid's image as a politicized symbol of cultural modernity in his 1992 novel Los misterios de Madrid. The novel was a return to the form and function of the nineteenth-century urban mystery novel. The year 1992 was one of celebrations throughout Spain, and Madrid was designated the 1992 European Capital of Culture (ECOC). The ECOC title was meant to signal Spain's graduation to democratic modernity and its new identity as a European capital. Madrid of Muñoz Molina contests this politicization of Madrid´s identity by gothicizing the capital. This Madrid is enigmatic and threatening, and it is the home of the conspiracies that undermine the capital's new image. In a year that celebrated Madrid's entree into European modernity, Muñoz Molina uses nineteenth-century literary modes to question Madrid's success story.  相似文献   
80.
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