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Initiated in 2004, the RICardo project focuses on bilateral trade data of all the world's countries from the early nineteenth century to the eve of the Second World War. The project includes the construction of a database and the creation of a website. It is a pioneering work in the field of historical trade statistics that aims at providing easy-to-access research material to the scientific community and at attracting a wider public to the history of trade relationships. The article emphasizes the originality of the project and sums up its various aspects by reviewing previous trade databases, clarifying the main features of historical trade statistics, and describing the construction and use of the RICardo website.  相似文献   
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This article studies the role of white, black and mulatto women during the last two years of the Haitian War of Independence, also known as the Haitian Revolution (1802–04). It might be expected that women's contribution was limited in wartime, but this article concludes otherwise. Desirable women were sought as prizes symbolic of a man's status in colonial society, or actively used their appeal to obtain political favours. Women of colour contributed to the rebellion in the fields of logistics, espionage and even combat. They also experienced martyrdom when convicted of aiding the rebel army. White women, in turn, were considered such an integral part of the colonial order that the rebels, led by Toussaint Louverture and Jean‐Jacques Dessalines, targeted them, as well as other civilians, during the fighting, then proceeded to exterminate all surviving whites after the rebel victory.  相似文献   
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Accurate reconstruction of diagenetic P‐T conditions in petroleum reservoirs from fluid inclusion data relies on valid measurements of methane concentration in aqueous inclusions. Techniques have been developed (Raman spectrometry) to provide sufficiently accurate data, assuming measured methane concentration has not been modified after aqueous inclusion entrapment. This study investigates the likelihood that organic acids derived from petroleum fluids and dissolved in formation water might suffer decarboxylation upon postentrapment heating within the fluid inclusion chamber, thereby generating excess CH4 in the inclusions. Four different experiments were conducted in fused silica capillary capsules (FSCCs), mimicking fluid inclusions. The capsules were loaded with acetic (CH3COOH) or formic (HCOOH) acid solution and were heated to 250°C for short durations (<72 h) in closed‐system conditions, with or without applying a fixed PH2. Reaction products were characterized by Raman and FT‐IR spectrometry. Results indicate that decarboxylation reactions did take place, at variable degrees of progress, and that measurable excess CH4 was produced in one experiment using acetic acid. This suggests that methane may be produced from dissolved organic acids in natural aqueous inclusions in specific situations, possibly inducing errors in the thermodynamic interpretation.  相似文献   
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With the aim of providing better control of shooting experiments performed with replicas of prehistoric projectiles, we have conducted an instrumental archaeology study on the efficiency of prehistoric projectile points by placing emphasis on their adhesion and ballistic characteristics. In order to avoid any reproducibility problems, hafting adhesives were made with controlled mixtures of commercial rosin (also called ‘colophany’) and beeswax added as a plasticizer. An original experimental device has been developed to instrument a bow, allowing the control of both the trajectories and the velocities of the different shoots. In the course of an experimental programme on Sauveterrian microliths from the Mesolithic period of the South of France, the experimental system was applied to composite replica projectile tips of Mesolithic hunters. Arrows being shot at transparent targets were filmed in order to evaluate the penetration length and residual damage. Interestingly, this study reveals that the properties of the mixture are highly dependent on the velocity of the arrows. It was shown that—contrary to previous experiments that usually used a mixture in which rosin predominates— the most efficient adhesive is made of 70 wt% beeswax with only 30 wt% rosin. This result is of great importance for improving further shooting experiments and overcoming the problems frequently mentioned due to the loss of the flint armatures before they reach the animal target, or at least before penetration. When using this appropriate mixture, the lateral armatures are resistant to most of the shots. Experiments performed on real boars’ flesh have also shown that the presence of lateral microliths allows the laceration inflicted on the target to be enlarged. Finally, a critical parameter has been identified, which is the location on the arrow of the microlithic element.  相似文献   
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Professional labour markets in Ontario, Canada, are culturally regulated to the disadvantage of foreign‐born and foreign‐trained immigrant practitioners. In this paper we draw on Pierre Bourdieu's concepts of institutionalized cultural capital and habitus to examine processes of distinction between foreign and Canadian‐trained professionals. Based on fieldwork investigating Ontario's professional engineering regulatory system as a case study, we interpret institutionalized cultural familiarity in the licensing criteria enforced by regulatory bodies as processes of distinction that undermine immigrants' access to the engineering profession relative to Canadian‐born and Canadian‐trained applicants. In addition to assessing the value of non‐Canadian credentials, regulatory bodies attempt to reproduce the social and cultural integrity of the professional membership by requiring applicants to internalize cultural norms specific to the profession as it is practiced in Canada. Licensing procedures can thus facilitate the cultural exclusion of immigrant practitioners  相似文献   
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