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21.
    
Just when molecular biology is arguably delivering on some of its long-promised medical applications—think mRNA vaccines, monoclonal antibody drugs, PCR testing, and gene therapies—the history of molecular biology has lost much of its shine. What not too long ago seemed like a burgeoning field of research with endless possibilities, is now often reduced to the “central dogma” that saw its apotheosis in the effort to sequence the human genome but has since unraveled. The essay will discuss several possible answers to this apparent paradox.  相似文献   
22.
    
al-Tikha is a mid to large Umm an-Nar (c. 2700–2000 BC) settlement situated near Rustaq at the back of the Southern Batinah coastal plain in the Sultanate of Oman that was discovered (or rediscovered) in 2014. The site is unique because its layout and spatial organisation are very largely (possibly completely) visible on the surface. This includes two separate areas of stone-built housing, a large pottery scatter of varying density, three or four typical Umm an-Nar round towers and a small cemetery consisting of at least four tombs, along with a few other features. The layout of the site is described and discussed in detail, in particular, in relation to what it might tell us about the nature of Umm an-Nar settlement and social organisation more generally. The location of the site within a pattern of repeating Umm an-Nar settlement along Wadi Far (Wādī al-Farʿī) is also described and discussed.  相似文献   
23.
Recent research in Paleolithic archeology has stressed the importance of temporal issues in assemblage interpretation. Archeological assemblages are temporal constructs, formed by the addition of an unknown number of depositional events. This temporal dimension is also evident at the artifactual level, since single artifacts may undergo different events of modification and/or uses over time. The recycling of previously discarded blanks for tool production is one of the best examples of the temporal nature of artifacts. The aim of this paper is to evaluate the importance of recycling in a Late Upper Paleolithic site, examining a type of artifact – burned tools – that has up to now been little used to approach this issue. Our results suggest that recycling was probably a significant component of Upper Paleolithic provisioning behavior, with important implications in site formation processes and the typological variability of assemblages. The expedient or curated character of recycling is also discussed.  相似文献   
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25.
The Maisin women of northeastern Papua New Guinea are among the last coastal Papuans to tattoo their faces. This article first describes the techniques and social process of Maisin tattooing. We then examine the resilience of the custom in light of changes in puberty rites and notions of gender. We argue that these contexts have lost their cultural salience as a result of the Maisins' incorporation into the larger Papua New Guinea society. Tattooing has acquired new significance as a marker of cultural identity in a multicultural setting and as a sign of the Maisin people's commercial success as makers of indigenous art.  相似文献   
26.
The purpose of this paper, prepared as a background document for the UNRISD/University of the West Indies conference on Economic Crisis and Third World Countries, is to provide a framework for consideration of societal changes accompanying economic recession and restructuring in Africa, Latin America and the Caribbean over the past decade. It is the central argument of the paper that adaptation to crisis should not be considered a temporary phenomenon, interrupting a single, lineal process of modernization which can be expected to resume its course once current difficulties are overcome. On the contrary, both crisis and adjustment have profoundly modified the structure of incentives within which individuals and households must attempt to ensure their livelihood, encouraging new patterns of behaviour with long-term implications for the nature of the economy, society and political practice. After a brief review of the macroeconomic background of crisis in each region, this central hypothesis is explored through a very preliminary analysis of the changing life chances of various kinds of upper, middle and lower income groups — emphasizing not only the costs but also the opportunities which have been associated with economic restructuring. Some individual and collective reactions to change are then considered, before raising a series of questions concerning the implications of crisis and adjustment for the state and civil society.  相似文献   
27.
A pair of mandibular rami from a brown bear (Ursus arctosL.) was found at the rock shelter of the Grande-Rivoire in the Castelnovian level. Both exhibit a peculiar deformation affecting the bone between the first and second molars and the roots of these teeth.The perfect symmetry of this deformation, the absence of pathological features, and the misplacement of the teeth suggest that a thong had been placed around the mandible while the animal was young; the mandible then grew around the thong.The interest of this find is that it both demonstrates the taming of a bear and the complexity of the relationships between humans and animals during the late Mesolithic.  相似文献   
28.
武友德 《人文地理》2000,15(3):69-72
西部不发达区域是我国自然资源密集地区,极具开发潜力,其经济成长采取自然资源转换模式具有客观必然性。但是传统的自然资源要素转换模式已严重制约着西部地区经济的持续发展。本通过对西部地区自然资源优势、资源开发中的技术结构和利益分配机制以及资源转换模式等问题的系统思考,提出了提升区域自然资源转换模式的构想。  相似文献   
29.
We propose a reassessment of Neandertal mobility strategies by crossing technological and zooarchaeological data. A broad comparative approach to the Middle Paleolithic series from western France shows that the Levallois and laminar flaking systems, the Mousterian of Acheulian Tradition (MTA) shaping system and the Quina and discoidal-denticulate flaking systems, vary significantly in terms of duration of reduction sequences, blank versatility and tool maintenance. These technological systems, which prevail in this context over different time periods, reflect distinct mobility strategies as a response to differing hunting practices. This new approach to Middle Paleolithic technologies and related mobility patterns gives new insights into Mousterian diversity. It also highlights the determinant role played by large game hunting strategies in the organization of late Neandertal societies.  相似文献   
30.
Nadung’a 4 is one of the single carcass pachyderm sites recorded in East Africa during the Lower and Early Middle Pleistocene. The site has yielded an abundant lithic assemblage in close association with the partial carcass of an elephant. Conjoined pedological, geoarchaeological, spatial, technological, and taphonomical analyses have been carried out to address the relationship between hominids and elephant. The resulting data are consistent with a non-fortuitous association between both categories of remains. The lithic artefacts do not match a classical Acheulean tool-kit, as would be expected for the time period ascribed to the site, and the functional patterns inferred from their analysis make this site radically different from other purported butchery sites. The implications of these original features are discussed.  相似文献   
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