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101.
The early occurrence of intentional heat treatment of silica rocks has recently become a key element in the discussion about the cultural modernity of prehistoric populations. Lithic vestiges are the only sources that remain of this process and the understanding of the material’s properties and transformations are essential for reconstructing the conditions and parameters applied during heat treatment. Several models of the structural transformations upon heating have been proposed in the current literature. These models are often contradictory and do not account for the most recent structural and mineralogical data on chalcedony. In order to propose a new model, we elaborated an experimental procedure and applied different techniques involving infrared spectroscopy, solid state NMR, X-ray diffraction and electron microscopy. The results show that the major transformation to happen is the loss of silanole (SiOH) and the creation of new Si-O-Si bonds according to the reaction: Si?OH HO-Si → Si-O-Si + H2O. This reaction starts between 200 °C and 300 °C and causes an increase in the hardness of the rocks. The maximal annealing temperature and the ramp rate are the functions of the ability of the structure to evacuate newly created H2O and depend on the size of the specimen and the volume of its porosity. These results also show that the annealing duration at maximum temperature can be relatively short (<50 min) for a sufficiently large amount of transformation to be accomplished.  相似文献   
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Philippe Le Billon 《对极》2006,38(4):778-801
This paper brings recent research on the geographies of commodities and the politics of ethical consumption to bear on contemporary spaces of violence. Focusing on the discourse of “terror”, it discusses the tactics and ambivalences of a human rights advocacy campaign seeking to stop the financing of belligerents by the diamond trade. I argue that the campaign successfully reconnected “violent” spaces of exploitation and “peaceful” spaces of consumption and achieved significant trade reforms in the diamond sector. Yet, with its inclusion of racialized images of Africa, its responsiveness to policy compromises and its overtaking by savvy marketing by Western mining companies, the campaign and its mediatization also had ambivalent outcomes: burnishing the “reputable” character of Western industrialized mining interests at the expense of their historical accountability, indiscriminately associating terror with poor young African men, and overlooking state violence.  相似文献   
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ABSTRACT

Palaeoparasitological investigation was conducted on a first set of samples from 13 sacrificed domestic camelids recovered from the pre-Hispanic Chimú culture site of Huanchaquito-Las Llamas, Peru. The aim was to establish the animals’ gastrointestinal parasite diversity and enlighten on their health status at the time of their death. To this end, 20 samples of coprolites and intestinal contents were analysed to check for the presence of parasite markers, i.e. preserved eggs and oocysts. Microscopic examinations revealed the presence of five taxa of helminths and protozoans in a majority of the tested animals (61%). Our analysis revealed the presence in some animals of protozoan oocysts belonging to the species Eimeria macusaniensis (phylum Apicomplexa). Our study is the first report of the possible presence of a parasite egg attributed to the order Plagiorchiida (family Fasciolidae) in ancient camelids. This preliminary study shows that there is interesting potential for conducting palaeoparasitological analysis at the site and that such analysis is promising for answering questions about the health status of the Huanchaquito-Las Llamas camelids.  相似文献   
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ABSTRACT

The site of Huanchaquito-Las Llamas, situated in the Moche Valley, Peru, dated to the Late Intermediate Period (AD 1100-1470), represents a single event mass killing of children and domestic camelids of the Chimu society. Reconstruction of the life histories of 82 camelid individuals based on stable isotope analysis of bone collagen indicates that they originated from the lowlands. Isotopic inter-individual variability indicates diversity in dietary sources, consisting of wild plants and cultigens, grown in water-limited and non-water-limited conditions, as well as a large proportion of C4 plants, suggesting that the animals originated from various herds that were differently managed. In contrast, uniformity in terms of restricted coat colour and young age could suggest that the animals derived from specialised herds. It is possible that the requirement in a short period of time for a massive number of animals meeting certain criteria exceeded the capacity of these herds. This study presents the largest isotopic dataset measured at a single pre-Hispanic site so far and the first to record herding practices for the Chimú society. Comparison with previous isotopic datasets shows differences between ritual and non-ritual groups, as well as diversity in pastoralism practises through time in the Central Andes.  相似文献   
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An exceptional discovery was made in 2013 in the northern French Alps, at the Grande Rivoire site in Sassenage (Isère department): an obsidian bladelet from Sardinia was found in a cultural horizon dated to about 5360–5210 cal b.c. The abundant arrowheads found with it are characteristic of the Early Neolithic in the South of France (Cardial/Epicardial). Yet there was no pottery or domestic fauna, and only discrete markers of farming. The typological, technological and micro-wear analysis of this bladelet, as well as the determination of the origin of the raw material, open new avenues of reflection for the neolithization of the northern Alps, in particular concerning the role played by the Early Neolithic cultures of northern Italy.  相似文献   
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Abstract

Aotearoa New Zealand is a nation of promise, potential and enigma: it was the first country in the world where women gained the vote in 1893 and now boasts the youngest woman world leader in 2017. It is also a postcolonial nation where structural racism, homophobia, and sexism persist, yet it has also given legal personhood to a river. Our Country Report foregrounds Aotearoa New Zealand feminist geographic scholarship that responds to, reflects, and sometimes resists such contrasts and contradictions at the national scale. We employ the lens of the 2017 national election to critically engage with current gendered and indigenous politics in the country. Analyzing these politics through three ‘feminist moments,’ our paper highlights the breadth and scope of current Aotearoa New Zealand feminist geographic scholarship and directions.  相似文献   
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