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371.
Abstract

Over the past two decades, southern Africa has experienced both exceptionally high AIDS prevalence and recurrent food shortages. International institutions have responded to these challenges by framing them as security concerns that demand urgent intervention. Young people are implicated in both crises and drawn into the securitisation discourse as agents (of risk and protection) and as (potential) victims. However, the concepts of security deployed by global institutions and translated into national policy do not reflect the ways in/security is experienced ‘on the ground’ as a subjective and embodied orientation to the future. This paper brings work on youth temporalities to bear on social and cultural geographies of in/security and securitisation. It reports on research that explored insecurities among young people in Lesotho and Malawi. It concludes that, by focusing on ‘threats’ in isolation, and seeking to protect ‘society’ as an abstract aggregate of people, global securitisation discourses fail either to engage with the complex contextualised ways in which marginalised people experience insecurity or to proffer the political responses that are needed if those felt insecurities are to be addressed. However, while securitisation is problematic, in/security is nonetheless an important element in young people’s orientation to the future.  相似文献   
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The punctuated equilibrium theory (PET) shows that government policy is mostly stable with occasional drastic change, which scholars attribute to institutional friction and limited information processing capacity. Although the existing PET literature predominantly focuses on democracies, scholars have started to apply the theory to authoritarian countries. Autocracies are a fertile testing ground for the theory's underlying mechanisms because they appear to experience less institutional friction but more informational restrictions than democracies. However, PET studies on autocracies are still rare. To deepen our understanding of the PET and the policy process beyond democracies, we conduct a systematic review of 88 Chinese language PET journal articles. We show that Chinese language PET research is increasing. Contrary to the English language PET literature, most Chinese studies are qualitative, while a key similarity is the weak operationalization of PET core concepts. The reviewed studies confirm a punctuated equilibrium pattern of policymaking in China but provide only limited evidence for more intense punctuations compared with democracies. Future PET research on China ought to use long-term data sets and examine institutional friction and information processing by policymakers. We also argue for more international exchange and comparative research to advance our understanding of the policy process in China and other autocracies.  相似文献   
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The stone technology from Mata Menge on Flores, Indonesia, is described, providing the first detailed analysis of the largest stone artefact assemblage from a stratified and securely dated Middle Pleistocene site in Southeast Asia. Technological analysis indicates a reduction sequence based on the centripetal, or “radial”, reduction of transported blanks. The implications for early hominin behaviour on Flores are considered.  相似文献   
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Damage generated by large and small carnivores is common in many Middle Pleistocene sites. However, identifying the predator that produces the faunal accumulations is often a difficult task. In order to recognize the main type of carnivore that acts on a faunal assemblage, a combination of several characteristics should be taken into account: taxonomic and skeletal element representation, age profiles, carnivore damage (location, frequencies and dimensions of tooth-marks, bone breakage and digested bones), degree of fragmentation and frequencies of coprolites. But, adding environmental characteristics and the ethology of non-human predators/scavengers is also important. All these aspects are applied to the faunal assemblage from the TD8 level of the Gran Dolina site (Sierra de Atapuerca, Burgos, Spain). Paleomagnetic data combined with ESR and U-series place the TD8 level at the beginning of the Middle Pleistocene, specifically circa 700 kyr ago. The TD8 level contains a large faunal accumulation primarily composed of ungulate skeletal elements, and to a lesser extent carnivore remains. This assemblage is characterized by an overrepresentation of fallow deer (Dama vallonetensis), a skeletal profile biased towards cranial remains and limb bones, diversity of ages at death, a high proportion of carnivore damage and tooth-marks of large size, and an absence of human activity. According to these data, the accumulation seems to have been produced primarily by large carnivores, possibly hyenas. This observation does not rule out the possible occasional activity by other carnivores. Nevertheless, the characteristics of the TD8 assemblage do not correlate entirely with those traditionally used to define carnivore dens. In TD8, there are (1) no immature carnivore remains (remains of just one young Mosbach wolf); (2) scarce traces related to the end stages of consumption and some anatomical connexions; (3) few coprolites; (4) high proportion of adult ungulates and; (5) high quantities of whole bones and epiphyses. From this perspective, the TD8 faunal assemblage seems to correspond to a succession of carnivore occupations that allows the development of a suite of features to identify the activities of several species of predators that may have used the cave in different ways and durations. This study aims to emphasize the importance of these analyzes in order to know the behaviour of different non-human predators/scavengers in the European Middle Pleistocene sites.  相似文献   
380.
In the context of an archaeological survey of the southern Argolid, Greece, studies have been carried out to elucidate the evolution of the landscape since its earliest known human occupation about 50,000 years ago. One of these studies was a detailed geological mapping of the late Quaternary alluvium and soils in the area. Dated by means of thorium-uranium disequilibria, archaeological finds, and historical information, seven periods of alluviation were identified, each of short duration relative to long intervening periods of stability and soil formation. The three earliest alluvial phases, falling before and during the last glacial interval, range from about 330,000 to 32,000 years in age. No alluviation accompanied the last glacial maximum around 20,000 years ago. In fact, a stable landscape persisted until about 4500 years ago, when debris flows and widespread aggradation in the valleys resulted from major slope destabilization and soil erosion, probably as a result of extensive land clearance in the Early Bronze Age. A subsequent stable period lasted through the many upheavals of the later Bronze Age, the Dark Ages, and the early historical period. It came to an end with a brief phase of alluviation between about 300 and 50 BC. Stability returned through the late Roman period, notwithstanding considerable expansion of the settled area. Another period of destabilization, this one marked by debris flows and hence major soil erosion, is poorly fixed in time, but probably coincides with expanded maquis clearance accompanying the resettlement of the area around AD 1000. Subsequent events of soil erosion and aggradation vary in nature and timing from one drainage to the next and, in some areas, continue today.Nature and chronology of the soil forming and alluviation events show that simple correlations with climatic events do not suffice to explain them. For the latter ones, past about 2500 BC, human activity seems to be the dominant cause, but once again the relation between cause and effect is not straightforward. Land clearing, or neglect of soil conservation efforts during economic downturns, appear to have a more devastating effect upon the landscape than do intensive land use or total land abandonment.  相似文献   
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