核桃丰产栽培技术分析

核桃为胡桃科的植物,是世界上著名的“四大干果”之一,核桃还是一种非常重要的有油料果树,不仅应用在人们的日常食用中,在目前的医药中也有很大的应用。由于核桃的结果期极长是一种具有经济效益的树木,也是目前在退耕还林的要求下,首选的种植林木。为了进一步的提高核桃的产量以及质量,近年来我国相关人员进行了多次的探讨与实验。笔者通过对于核桃丰产栽培技术的有效研究以及分析,提出了以下观点仅供参考。     

美国考古学:过去与未来

1935年12月28日,三十一位考古学家聚会于匹茨堡,标志着美国考古学会——一个“美国专业的和非专业的考古学者得以表达自己思想”的团体——的创立。1985年5月近两千名考古学者,包括三位学会的创始人在丹佛隆重集会,庆祝学会创建五十周年.《美洲古物》上的一篇回顾文章刊载了这次重要会议,六百三十四位专家的发言、公开演说和一整天的学术讨论会评价了这门学科     

冒险家档案

从本期开始，我们将用一年时间刊登探索者年度特辑，讲述那些本着探索精神不断挑战极限，甚至将生死置之度外的人们的故事。     

察合台文历史著作《幸福天堂》

《幸福天堂》是一部关于希瓦汗国历史的重要著作，在研究边疆史地以及乌兹别克人历史文化方面具有很高的学术价值。其内容涉及希瓦汗国的汗室家族世系、汗国的体制和官制、社会经济、军事制度、历史地理、当时战争情况、风土人情等诸多方面。本文在前人的研究基础上，对该书的结构与体裁、作者生平、史料来源、史料价值以及书中所出现一些文献做一简要的论述。     

拾穗者

《拾穗者》描写了一个农村中最普通的情景:秋天,金黄色的田野看上去一望无际,麦收后的土地上,有三个农妇正弯着身子十分细心地拾取遗落的麦穗,以补充家中的食物。她们身后那堆得像小山似的麦垛,似乎和她们     

喀喇汗国文学发展原因探微

喀喇汗国是回鹘史上一个极其辉煌的时期。由于生产方式的转变、多种宗教的融合等原因,这一时期的文学得到了蓬勃发展,代表作家和代表作品丰富,值得深入研究。     

The Maudsley Hospital and the Rockefeller Foundation: the impact of philanthropy on research and training

Opened in February 1923 to raise the status of academic psychiatry in the UK, the Maudsley Hospital struggled to secure grant income. Without a track record of published research and lacking internationally recognized clinicians, it failed to impress the British Medical Research Council. To challenge leading U.S. and German departments of neuropsychiatry, Edward Mapother, the medical superintendent, looked overseas for investment in an "institute of psychiatry." Intense lobbying and a modified strategy for research and training designed to meet the Rockefeller Foundation's prioritization of psychiatry and medical specialization ultimately led to a significant endowment. Alan Gregg and Daniel O'Brien at the Foundation played a pivotal role in re-defining the Maudsley's programs of research and teaching. Pressure on Mapother to attract funding was matched by that on administrators required to show that their philanthropy had yielded tangible gains in public health. While wealthy charities, like the Rockefeller, often had a vision of the direction that they wished to pull medical science, and they provided much needed income, the impact of their policy agenda was not without drawbacks. Institutions unwilling to embrace a charity's philosophy were unlikely to secure grants, while those that did might find themselves drawn into less optimal areas.     

Learning from mistakes: early twentieth-century surgical practice

Archibald Watson was an Australian anatomist and surgeon who kept operating theater diaries. He made detailed notes on the work of surgeons that he observed in Britain and North America, as well as in Australia. Watson's diaries provide significant evidence that early twentieth-century surgeons did not just apply scientific knowledge produced somewhere else. They generated new surgical knowledge themselves and worked within a culture that valued innovation. Some of the surgeons observed by Watson practiced in academic centers and regularly engaged in laboratory research, but most did not. Nevertheless, it is clear that whether in Australia, Britain, or North America, the active search for improved techniques was a routine feature of the practice of full-time surgeons. In the process, they often made mistakes--or rather, they often did things with which at least some of their colleagues did not agree. Much of surgical practice was contestable. Doing things the "right" way and finding better ways to do things were overlapping categories; but it is often difficult or impossible to draw any distinction at all between doing things the "wrong" way and failed attempts at finding a better way to perform an operation. This article examines some aspects of the relationship between scientific ideas, clinical experience, contestable errors, and the generation of new knowledge through surgical practice.     

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。