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Superficial deposits (residual, colluvial, alluvial) are important as environmental resources in tropical environments. An understanding of their formation through varying time periods is essential to a correct interpretation of their economic and hazard potentials. This requires an integration of process studies with a reconstruction of longer term development. Saprolite formation is considered over 105‐107 yr, while colluvial and alluvial sediments are commonly Late Quaternary (103‐105 yr) in age. The importance of Quaternary environmental changes in the humid tropics to an understanding of heavy mineral placer deposits in West Africa and Indonesia is illustrated. It is concluded that geomorphologists can often make their most important contributions to developing areas by offering a sound interpretation of landsurfaces and their underlying deposits for engineers, geologists and pedologists, with whom a close working relationship is essential.  相似文献   
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This paper draws on a study of gender and politics in the Australian parliament in order to make a contribution to methodological debates in feminist political science. The paper begins by outlining the different dimensions of feminist political science methodology that have been identified in the literature. According to this literature five key principles can be seen to constitute feminist approaches to political science. These are: a focus on gender, a deconstruction of the public/private divide, giving voice to women, using research as a basis for transformation, and using reflexivity to critique researcher positionality. The next part of the paper focuses more specifically on reflexivity tracing arguments about its definition, usefulness and the criticisms it has attracted from researchers. Following this, I explore how my background as a member of the Australian House of Representatives from 1987 to 1996 provided an important academic resource in my doctoral study of gender and politics in the national parliament. Through this process I highlight the value of a reflexive approach to research.  相似文献   
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There is a continuing need in cartographic communication for reserarch directed toward better understanding of the perceptual properties of maps, particularly as they interrelate between map author and map reader (percipient). This research explores that area by examining the perceptions of authors of maps utilized in science fiction and fantasy, and readers who encounter these maps in the literature.

The first phase of the research demonstrates that authors generally have a positive attitude toward the literary map and view them as critical to the formulation of a story and important to proper understanding of the narrative. By contrast, readers tested in the second part of the study view literary maps as superfluous and in general have a negative attitude toward them.

The literary maps employed in this research fail to communicate effectively with the reader. Poor cartographic communication and the negative attitude of readers toward the literary map is explained in terms of functional illiteracy.  相似文献   
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The Roman sites of the Cheshire Plain have, with the exception of Middlewich, received little excavation in recent years. Indeed there has been no previous excavation at Northwich. Despite a very large degree of disturbance and other archaeological difficulties, the excavations established the existence of a two-phase auxiliary fort of Flavian origin on the site. After abandonment in the mid-2nd century, part of the area examined was occupied by furnaces associated with probable metal working. Rescue work during redevelopment also led to the discovery of a pottery kiln with stamped mortaria of the potter concerned, and an iron helmet from the military period. The coarse pottery and samian are also of particular interest. The former included several groups of fairly localized material from the Cheshire Plain an area from which comparatively little stratified coarse-ware has been published; the latter includes a group forming, it is suggested, the repertoire of a South Gaulish potter or workshop of the Domitianic—Trajanic period.  相似文献   
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This paper presents a geochemical analysis of fragments of bituminous amalgam from H3, As‐Sabiyah (Kuwait), and RJ‐2, Ra's al‐Jinz (Oman). The fragments bear barnacles on one side and reed impressions on the other, and are thought to have been part of the coating of reed‐bundle boats. The material from H3 dates to between 5300–4900 BC, while that of RJ‐2 dates to 2500–2100 BC. Samples from both sites were geochemically compared to archaeological and ethnographic material from Kosak Shamali (northern Syria, c.5000–4400 BC), RH‐5 (Oman, 4400–3500 BC) and Baghdad (central Iraq, 1900 AD). The composition of the bituminous amalgams was studied in detail. Rock‐Eval Pyrolysis gave a measure of Total Organic Carbon in the samples, and allowed an initial comparison of the data sets using various parameters. Examination of the proportions of soluble and insoluble organic matter allowed an assessment of the quantity of vegetal matter added to the bitumen to make the bituminous amalgam. The composition of the Ra's al‐Jinz material was studied using X‐Ray Diffraction analysis and thin‐section petrography, in order to assess the proportions of various minerals in the bituminous amalgams. It was concluded that the recipe for the bituminous mixture used to coat reed‐bundle and wooden boats did not differ significantly from that commonly used to make ‘mortar’ for architectural purposes in Mesopotamia. Traces of animal fats or fish oils were not found in the analysed Ra's al‐Jinz material, in contrast to previous hypotheses regarding the composition of the mixture. Comparison of the gross composition of extractable organic matter (the constituents of pure bitumen, soluble in chloroform or dichloromethane) showed the progressive effects of weathering on the samples. The isotopic composition of the bituminous material from H3 and the other sites was then compared to that of bitumen seeps and crude oils from Mesopotamia, Iran and Oman. The most significant result is that the material from As‐Sabiyah originated in Kuwait, at a surface seep at Burgan, while the material from Ra's al‐Jinz had a source in northern Mesopotamia.  相似文献   
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African Archaeological Review - Two recent documentaries promote a “Black Pharaohs” theme in which Kushite rulers overthrew the superior Egyptians and ruled Egypt (Twenty-Fifth...  相似文献   
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东亚稻作起源研究的新进展   总被引:1,自引:0,他引:1  
农业起源是国际学术界的重大课题之一,而中国的稻作起源研究由于其丰富的材料在这方面取得了丰硕的成果,引起了世界的广泛关注。《东亚稻作起源研究的新进展》一文是加拿大著名植物考古学家加里·克劳福德和沈辰博士综合中国、日本和韩国近年来稻作考古方面的发现和研究成果所作的述评,在高度评价东亚稻作起源研究成就并赞同某些观点的同时,也提出了自己的一些看法。首先,作者赞同中国水稻的本土起源说,认为可能起源于长江中下游地区,是一种热带型粳稻。中国考古发现中未见籼稻,籼稻系起源于南亚地区。但是,对于当前所发现一些最早的水稻遗存(如玉蟾岩、彭头山、贾湖,甚至河姆渡)是否为驯化种,作者却持基本否定态度,认为仍然属于野生种,甚至没有足够的考古证据证明是人为采集利用的结果,直到较晚期的龙虬庄,水稻遗存才有了明显的人工干预迹象。农业起源是一个数千年的漫长过程,而非一种突发的事件,这也是国际学术界的主流观点。另外,作者还对中国学者对野生稻的生物分类方法提出了意见,认为目前的分类方法不够细致,还应该作进一步的划分。作者比较重视稻作起源中的技术手段,对日本学者的DNA方法表示赞赏,认为它解决了如粳、籼不同起源等方面的一些重大问题。最后,作者还提到要重视起源问题的文化和生态背景,强调了多学科系统协作的重大意义。  相似文献   
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