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1.
Significant advances in our understanding of ancient agricultural practices in the Americas have been made in recent years. This review of the literature focuses on studies published between 1987 and early 1994. Issues pertaining to the transition from foraging to farming include the habitability of the American tropics prior to the development of agriculture, theories on plant domestication and the origins of agriculture, regional syntheses of agricultural development, and the origin, evolution, and dissemination of domesticates in the Americas. Other topics reviewed include new techniques that have recently been applied to the study of prehistoric agriculture in the Americas, various approaches to the study of agricultural change, and ways in which research on ancient agricultural practices is being applied in modern experimental agriculture and rural development projects.  相似文献   
2.
Recent fieldwork has considerably increased our knowledge of early Holocene settlement in Southwest Arabia. Neolithic settlement occurred within an environmental context of increased monsoonal moisture that continued during the mid-Holocene. A now well-attested Bronze Age exemplified by village- and town-scale settlements occupied by sedentary farmers developed toward the end of the mid-Holocene moist interval. The high plateau of Yemen was an early focus for the development of Bronze Age complex society, the economy of which relied upon terraced rain-fed and runoff agriculture. On the fringes of the Arabian desert, the precursors of the Sabaean literate civilization have been traced back to between 3600 and 2800 B.P., and even earlier, so that a virtually continuous archaeological record can now be described for parts of Yemen. In contrast to the highlands these societies relied upon food production from large-scale irrigation systems dependent upon capricious wadi floods. Bronze Age settlement, while showing some links with the southern Levant, now shows equal or stronger linkages with the Horn of Africa across the Red Sea. Although some regions of Yemen show breaks in occupation, others show continuity into the Sabaean period when a series of major towns grew up in response to the incense trade with the north. It is now clear that these civilizations grew up on the foundations of earlier Bronze Age complex societies.  相似文献   
3.
ABSTRACT

Early colonial officials and other newcomers frequently lamented the poor copra production in Wallis and Futuna, positioning the continued consumption of coconuts by Islanders as a waste. This article explores the contested uses of coconuts and the divergent visions of the islands’ landscape and future held by Islanders, officials, missionaries and traders during opening decades of French colony rule. In particular, a variety of incidents in the 1920s – from an indigenous co-operative to French expulsions – highlight the centrality of the emergent copra trade to the social and political status of these different groups. More broadly, however, the article demonstrates the failure of elites – both indigenous and newcomer – to substantially increase copra exports prior to the Depression in 1930, indicative of the limits of their ability to demand labour and transform the lifeways of the wider population.  相似文献   
4.
Regional design, long a backbone for spatial planning, even if under other names, has become topical again for two reasons – as a key strategy and as a key tool in spatial management. This is due to several reasons. New conditions of urbanization that result from the convergence of several factors highlight the need for spatial strategy formation and application at supra-metropolitan scales. These new conditions include globalization, climate change, booming urban population, increased mobility and interconnectivity, and new infrastructure technologies. These forces driving urbanization today and into the future play out at the urban scale, which is increasingly encompassed in the city-region. The solutions to the impacts and problems that these forces cause must be dealt with by a strategic urbanism at a scale that matches. This scale of urbanism can be denoted as regional design. To justify these claims and to understand the origins of regional design and its relevance today and into the future, the master strokes in its history are presented next. After that, we discuss current concepts and practices in regional design. In conclusion, we offer answers to the question: why a resurgence of regional design?  相似文献   
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VandenBerg, Alfons H.M., November 2017. Fragmentation as a novel propagation strategy in an Early Ordovician graptolite. Alcheringa 42, 1–9. ISSN 0311-5518.

Catenagraptus communalis gen. nov. sp. nov. is a late Floian (Early Ordovician) graptolite from Victoria, Australia, only found as fragments, with each fragment resembling an assemblage of uniserial tubarium-like structures (pseudotubaria) connected by threads (aulons). Individual pseudotubaria consist of a fallosicula and a stipe, both of which are linked by aulons to other pseudotubaria. Adjacent pseudotubaria are in a parent–offspring relationship. Aulons can be generated from both the proximal and distal extremities of fallosiculae, and from the ends of stipes. The aulons are interpreted to have been grown by the zooid that occupied either the fallosicula or the terminal theca of the stipe. Aulons were pathways for a zooid that built a fallosicula at the end of the aulon. This process was repeated to form the assemblage. None of the assemblages contain a true sicula, which suggests that the assemblages present evidence of a new, asexual propagation strategy that involved fragmentation and dispersal. As this interpretation is radical, other models explored are partial sclerotization and modified sicular spines.

Alfons H.M. VandenBerg [], Museum Victoria, GPO Box 666, Melbourne 3001, Victoria, Australia.  相似文献   

7.
张威 《安徽史学》2015,(6):118-127
1971年印巴危机是冷战时代一次具有重大国际影响的地区危机。危机期间,因受东巴内战与印巴冲突的双重影响,大量东巴居民逃往印度,沦为难民。东巴难民持续涌入印度不仅是东巴危机转变为印巴危机的主要诱因,同时也是导致南亚持续紧张、敌对氛围难以消解的重要根源。为妥善解决难民问题,美国积极谋划,投入大量人力、物力、财力,意图妥善解决难民问题,化解危机。但是美国采取的积极措施并未减缓危机冲突的不断升级。在处理难民问题的过程中,美巴政策协调趋于一致,而印度与美巴在难民问题上的政策倾向却渐行渐远。归根究底,是否应该在难民问题上附加最终促成东巴独立的政治条件是美巴与印度的根本分歧所在。而这一根本分歧的悬而未决最终成为引爆第三次印巴战争的导火索。  相似文献   
8.
Since the late 1990s, migration of single women from the rural north to the urban south in Ghana has been making up a growing share of migrant streams. While the livelihood strategies of these migrant women in their southern destinations have been recently examined, the experience of reintegration for those who return to their place of origin has rarely been studied. Drawing on qualitative research with migrant women, returned migrant women (RMW) and their family members, this study examines everyday reintegration experiences of RMW within their households in a rural Dagomba community in Northern Region, Ghana. We conceptualise the household as an arena of everyday life wherein RMW exercise agency to learn to generate livelihoods that support their own as well as household members’ joint well-being. We combine this conceptualisation of household with feminist scholars’ recognition of gender as situated process. Our conceptualisation makes it possible to illuminate gender dynamics around the everyday repetitive decision-making acts that constitute livelihood generation as performed by RMW within specific intra-household dynamics in the context of reintegration in the situated community. Through the examination of the diverse and contradictory ways in which RMW exercise agency in making decisions about livelihood strategies within their households in the studied community, we show how the everyday repetitive acts of RMW contribute to micro-transformations of a situated gender ideology.  相似文献   
9.
Recognition and respect for sexual minorities in Hong Kong is still a contested area. Public sexual identity politics in Hong Kong has been framed by traditional Chinese gender ideology and imported Christian beliefs which are profoundly negative. Focusing on the interpersonal relationships in three spheres of life, the research adopted the sociological perspective of personal life and the feminist geographers’ idea of spatialization of identity management to analyze how the sexual self of sexual minorities has been marginalized and excluded in intimate social spaces of family, church communities and schools in Hong Kong with specific spatial practices and different forms of power/knowledge. By examining overlooked intimate injustice in personal life, this study illustrates that identity conflicts between Christianity and non-heterosexuality in everyday life is constructed through misrepresentation, misrecognition, harassment and exclusion in intimate relationships. Different types of knowledge are being used to reiterate pre-existing norms and institutionalized patterns of cultural value that constitute the sexual minorities as comparatively unworthy of respect. These micro-political processes involve both conformity and resistance to gender and sexual stereotypes. Participants managed to develop spatial coping strategies such as concealment, compartmentalization, confrontation and alternative sources of support to manage their lives with dignity and self-esteem.  相似文献   
10.
Few men arguably shaped the trajectory of American foreign policy in the twentieth century as durably and profoundly as Henry L. Stimson. After all, Stimson was not only directly involved in many consequential decisions dealing with highly important matters of war and peace, but was also a major influence in the United States’ more proactive involvement in extra-territorial affairs. For Stimson, it was simply wishful thinking to presume that the United States could forever disengage itself from far-reaching occurrences in other parts of the globe. Accordingly, he thought it just as critical to anticipate international problems as it was to successfully resolve them afterwards, with the result that he became an ardent and early proponent of a much more sophisticated global strategy after the Second World War. In that context, however, most historians have primarily focused on Stimson's role in the development and use of the atomic bomb against Imperial Japan, though arguably less on his more sweeping grand strategic designs. Consequently, the present article will attempt to offer a more comprehensive analysis of Stimson's grand strategic designs, particularly as they related to his vision and reflections on the necessary ingredients of a more peaceful, stable and secure interstate system.  相似文献   
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