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161.
In technological approaches to prehistoric industries, there is currently a renewed interest in the transformation of osseous materials. This approach requires the construction of a technical reference base of manufacturing stigmata, as well as of the procedures and methods used to produce tool blanks.One of the better known processes for the production of blanks in the Upper Palaeolithic is extraction by a double longitudinal groove, observed only in the Gravettian. Aurignacian artefacts indicate that during this period blanks were obtained through a procedure of longitudinal fracturing (splitting) or diffuse percussion fracturing. The manner of implementing these procedures is, however, still poorly known.In order to better characterise this stage in the manufacturing of blanks for antler points, we conducted an experimental study. Based on a thorough analysis of the Spanish archaeological materials, we tested the procedure of fracturing by indirect percussion on deer antler. The results provide new criteria for the identification of blanks and their manufacturing processes. They also emphasize the possibility of predetermining the size of the blank and, consequently, the size of future projectile point.  相似文献   
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For children and young people in street situations, to give up street life is easier said than done. The study reported in this article aims to contribute to the field of children and young people in street situations by introducing the voices of parents whose daughters live on the streets. In biographical narrative interviews, we asked parents together with street educators from Bolivia to share their stories of girls entering and leaving street life. Our findings showed that a child's act of running away made parents aware about their parenting, leading to new openings and possible renewed social bonds with their children. At the same time, street educators’ stories exposed the importance of the family support during the process of exiting street life. Nevertheless, even though parents no longer want to stand on the sidelines, the stories also revealed that parents are still forgotten throughout interventions with street children in Bolivia.  相似文献   
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This article examines Anglo–Dutch rivalry in the Banda Islands in the period from 1609 to 1621, with a particular focus on the process of claiming initiated by the Dutch East India Company (VOC) and English East India Company (EIC). Historians have paid little attention to the precise legal justifications employed by these organisations, and how they affected the outcome of events. For both companies, treaties with Asian rulers and peoples were essential in staking out claims to trade and territory. Because so many different parties were involved, individual documents had to serve multiple purposes, both on the ground in the East Indies and at the negotiating tables back in Europe. Whenever a VOC or EIC official presented a treaty to a Bandanese leader, he had to recognise local power structures in the Spice Islands, but also needed to consider his European competitors in the area, his superiors in Batavia or Bantam, and the company directors back in Amsterdam or London. Consequently, the safest and most reliable course of action was to make as many arguments as possible, piling them on top of one another. The result was an inherently messy process of claiming, yet one that was also clearly intelligible to most parties involved, including Asian rulers and peoples. A constantly changing legal suite extended to freedom of trade and navigation, contracts and alliances with native peoples, just war, conquest, actual possession, and the (perceived) surrender of native sovereignty to European authorities.  相似文献   
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Systematic use of animal manure has been demonstrated to be detectable in the plant δ15N value but evidence of manure affecting isotopic composition is mainly based on studies of fresh plant material. These findings can potentially be applied to archaeobotanical assemblages and thus provide information about prehistoric manuring practice. Prehistoric grains are generally found in a charred state of which the exact charring conditions are unknown but most likely often multifarious. In this study we examined the influence of grain weight and a range of charring conditions with regards duration, temperature, oxygen availability, and manuring. The charring was applied to emmer, spelt and naked barley with assessment of weight loss, N concentration and δ15N. There were only small and non-systematic variations in δ15N in relation to grain weight class. We also found that charring did not distort δ15N in either a systematic or substantial way and conclude that manuring most likely will be detectable in archaeobotanical charred grains. As certain within-grain variability in δ15N existed, especially in the intensively manured grains, the resolution of this kind of information should be carefully considered. However, despite attempts to deliberately tamper and distort the grain δ15N signature, the changes observed in this study were too small to be of any consequences for the archaeobotanical applicability of the method. Thus the isotope method offers unique evidence about prehistoric manuring practice.  相似文献   
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