High-resolution sclerochronological analysis of the bivalve mollusk Saxidomus gigantea from Alaska and British Columbia: techniques for revealing environmental archives and archaeological seasonality

The butter clam, Saxidomus gigantea, is one of the most commonly recovered bivalves from archaeological shell middens on the Pacific Coast of North America. This study presents the results of the sclerochronology of modern specimens of S. gigantea, collected monthly from Pender Island (British Columbia), and additional modern specimens from the Dundas Islands (BC) and Mink and Little Takli Islands (Alaska). The methods presented can be used as a template to interpret local environmental conditions and increase the precision of seasonality estimates in shellfish using sclerochronology and oxygen isotope analysis. This method can also identify, with a high degree of accuracy, the date of shell collection to the nearest fortnightly cycle, the time of day the shell was collected and the approximate tidal elevation (i.e., approx. water depth and distance from the shoreline) from which the shell was collected.Life-history traits of S. gigantea were analyzed to understand the timing of growth line formation, the duration of the growing season, the growth rate, and the reliability of annual increments. We also examine the influence of the tidal regime and freshwater mixing in estuarine locations and how these variables can affect both incremental structures and oxygen isotope values. The results of the sclerochronological analysis show that there is a latitudinal trend in shell growth that needs to be considered when using shells for seasonality studies.Oxygen isotope analysis reveals clear annual cycles with the most positive values corresponding to the annual winter growth lines, and the most negative values corresponding to high temperatures during the summer. Intra-annual increment widths demonstrate clear seasonal oscillations with broadest increments in summer and very narrow increments or no growth during the winter months. This study provides new insights into the biology, geochemistry and seasonal growth of S. gigantea, which are crucial for paleoclimate reconstructions and interpreting seasonality patterns of past human collection.     

埃及晚期的木基质彩画：赛加拉和法国博物馆

埃及文明在矿物方面的知识总是超出了我们的想象。这方面就包括使用多种黄色矿物绘制颜色相近的色彩。对这些颜料的准确鉴定将拓展人们在彩画方面的研究。画家所使用的颜料非常丰富,除了同时代直接从埃及地面采集的自然颜料外,还有大量像埃及蓝这类合成颜料的应用。对法国的这些藏品的研究将使人们可以追溯几个世纪以来这些颜料的演变和替代过程以及一些从其它地区尤其是东方国家引进颜料的过程。一些颜料的稳定性及其它特性使得其保存状况令人惊讶。卢浮宫博物馆在塞加拉的任务是进行一个埃及晚期（公元前378年一公元前341年）典型群葬墓的发掘工作。发掘出的木质棺材上记载了该墓葬的埋藏时间是Nectanebo二世法老执政的第2年,这是埃及第三十王朝的最后一任法老。该研究涉及以木质为基材的出土物,它包括二十个完整的或破碎成碎块的像盒子一样的棺材。研究通过在双筒显微镜下对文物进行微量取样,而后将样品进行扫描电子显微镜一能谱分析以及显微拉曼光谱分析,从而确定样品中矿物的成分。此外还对样品进行微量化学分析以确定其残存的痕量胶料。彩色颜料包括埃及彩画同时代的传统颜料一黑色,白色,红色,黄色,蓝色,绿色和镀金,同时还包括一些不常见的粉红色或橘色颜料,它是一种外来的、易碎的颜料,成分为五硫化二砷,又称雄黄。     

La Place des femmes dans l’histoire ou les enjeux d’une écriture

The history of women in France has not yet achieved the recognition it deserves. As a category, it is ill identified and remains on the margins of the «other» history. The history of women will remain bordeline unless we reinstate the historicity of the tensions inherent in gender relations, which up to now have been excluded as an object of study in the field of political history, which itself has been conceptualized outside the framework of power relations. A complete renewal of the way in which history is written is thus crucial. What is at stake lies between a linear, continuous history and the historical discontinuities that emerge in its gaps; between representative female individuals, as objects of representation, and the critical subjects who strain against representation as a form of power.     

Le gouvernement de la loi est-il un thème républicain?

Liberty is submission only to laws. This idea, according to Turgot, is a very republican one, and it belongs indeed to the classical republican tradition. It is, nonetheless, a mostly modern idea, not necessarily a republican one. It appears in the criticism of absolute monarchy: the importance of making the law is granted, but that anybody could be above the laws is rejected. For Montesquieu, moderate monarchy is the rule of law, of standing laws which provide the individual action with the conditions its rationality requires. But Rousseau makes a republican system of the rule of law, by identifying self-government and autonomy. By linking liberty and law, he stresses the political existence of liberty: since Turgot, it has been objected, inside liberalism, that such a political device jeopardizes natural rights.