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Eastern Europe lacks cohesion partly arising from a history of ethnic tension. Ways are now being found to overcome historic conflicts over alternative political structures, as the enlargement of membership for European institutions requires greater equality of rights at the same time as support and security is extended. Thus while ethnicity, as a political, social and cultural entity, persists in Eastern Europe as an essential element at the local level, it is now being seen more positively as cultural diversity and thus more compatible with democracy and a positive asset to national well-being. Multi-ethnic states are proving to be viable and some of the most intractable inter-ethnic problems (linked with the Hungarian minorities) are being addressed constructively. Yet there are signs that the southern part of the region is being marginalised regarding foreign investment. Also there is unease that European values are not being embraced unconditionally in parts of the Balkans. Recent military intervention has created fresh problems, committing the West to continued economic and political support to strengthen its stance on democracy and minority rights. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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The scientific community is developing new global, regional, and sectoral scenarios to facilitate interdisciplinary research and assessment to explore the range of possible future climates and related physical changes that could pose risks to human and natural systems; how these changes could interact with social, economic, and environmental development pathways; the degree to which mitigation and adaptation policies can avoid and reduce risks; the costs and benefits of various policy mixes; and the relationship of future climate change adaptation and mitigation policy responses with sustainable development. This paper provides the background to and process of developing the conceptual framework for these scenarios, as described in the three subsequent papers in this Special Issue (Van Vuuren et al., 2013; O’Neill et al., 2013; Kriegler et al., Submitted for publication in this special issue). The paper also discusses research needs to further develop, apply, and revise this framework in an iterative and open-ended process. A key goal of the framework design and its future development is to facilitate the collaboration of climate change researchers from a broad range of perspectives and disciplines to develop policy- and decision-relevant scenarios and explore the challenges and opportunities human and natural systems could face with additional climate change.  相似文献   
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The Cook Inlet beluga whale, one of five Alaskan stocks, is genetically distinct and geographically isolated from other populations. Historically, Cook Inlet whales were hunted commercially, for sport, and for subsistence uses. The Marine Mammal Protection Act (MMPA) of 1972 ended commercial and sport hunting; in 1999, subsistence hunting voluntarily ended. In 2008, Cook Inlet beluga whales were listed as endangered under the Endangered Species Act after annual aerial surveys indicated the population was not recovering as expected. A combination of natural and anthropogenic factors may be affecting this population’s recovery. This study documented traditional and local ecological knowledge of Alaska Native subsistence hunters and fishers and commercial fishers through participatory research to explore ecological changes in Cook Inlet over time and to identify potential factors impacting this beluga whale population. Study results identified potential environmental and climate change factors including prey competition, health of beluga and their prey, and the presence of killer whales, the majority of which may indicate an ecosystem regime shift in the Cook Inlet region. Human-related factors included fisheries management and related prey reduction, water contamination, and anthropogenic-related noise. These results corroborate identified threats to beluga whales and also identify potential new areas of scientific investigation and management. As such this study demonstrates the value of incorporating traditional and local ecological knowledge into ongoing science and management.  相似文献   
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Immigration has become a leading topic of Italian political discourse and culture over the past decade, but international migrants also play a crucial role in the transformation of political culture at the scale of everyday practices. In the northern Italian industrial city, Turin, migrants from various parts of Africa, Latin America and Southeast Asia bring into relief the deconstruction of postwar labor in Italy, and contribute widely to shifting political practices and identities. Contemporary migrants from diverse ethnic backgrounds are discriminated against in similar ways, and are in the historically peculiar position of building diasporic politics. In Turin, first generation migrants have helped lead newcomers toward active participation in local politics, from the shop floors to the labor unions, and to inter-ethnic and feminist associations.  相似文献   
108.
A method for estimating the amplitude and time-delay parameters for signals that can be represented as a sum of a number of scaled and delayed replicas of a known signal in the presence of nonwhite Gaussian noise is presented. The method is based upon the principles of maximum likelihood (ML) estimation, but at certain key points simplifying assumptions are made that result in a computationally practical estimation scheme. The results are compared with other related results in the literature. Simulation results are presented which support the methods derived.  相似文献   
109.
Mars Express (MEX) Analyser of Space Plasmas and Energetic Atoms (ASPERA-3) data is providing insights into atmospheric loss on Mars via the solar wind interaction. This process is influenced by both the interplanetary magnetic field (IMF) in the solar wind and by the magnetic ‘anomaly’ regions of the martian crust. We analyse observations from the ASPERA-3 Electron Spectrometer near to such crustal anomalies. We find that the electrons near remanent magnetic fields either increase in flux to form intensified signatures or significantly reduce in flux to form plasma voids. We suggest that cusps intervening neighbouring magnetic anomalies may provide a location for enhanced escape of planetary plasma. Initial statistical analysis shows that intensified signatures are mainly a dayside phenomenon whereas voids are a feature of the night hemisphere.  相似文献   
110.
We present the first results from the ion mass analyzer IMA of the ASPERA-3 instrument on-board of Mars Express. More than 200 orbits for May 2004-September 2004 time interval have been selected for the statistical study of the distribution of the atmospheric origin ions in the planetary wake. This study shows that the martian magnetotail consists of two different ion regimes. Planetary origin ions of the first regime form the layer adjacent to the magnetic pile-up boundary. These ions are accelerated to energy greater than 2000 eV and exhibit a gradual decreasing of energy down to the planetary tail. The second plasma regime is observed in the planetary shadow. The heavy ions (considered as planetary ones) are accelerated to the energy of the solar wind protons. Obviously the acceleration mechanism is different for the different plasma regimes. Study of two plasma regimes in the frame referred to the interplanetary magnetic field (IMF) direction (we used MGS magnetometer data to obtain the IMF clock angle) clearly shows their spatial anisotropy. The monoenergetic plasma in the planetary shadow is observed only in the narrow angular sector around the positive direction of the interplanetary electric field.  相似文献   
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