18 research outputs found

    Existence of axially symmetric static solutions of the Einstein-Vlasov system

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    We prove the existence of static, asymptotically flat non-vacuum spacetimes with axial symmetry where the matter is modeled as a collisionless gas. The axially symmetric solutions of the resulting Einstein-Vlasov system are obtained via the implicit function theorem by perturbing off a suitable spherically symmetric steady state of the Vlasov-Poisson system.Comment: 32 page

    Finishing the euchromatic sequence of the human genome

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    The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

    Information society and the countryside: can internet-based systems bring income alternatives to rural areas?

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    The paper reviews seven types of Internet-based technologies and services that may be especially suitable for rural areas. Its main focus is to analyze, which of these applications could promote rural development and prevent further economic and socio-demographic decline in peripheral rural areas. In particular, we will analyze whether these technologies have the potential to create income alternatives for the rural population. The paper also criticizes the current rural development policy of the European Union, which is heavily biased towards the agro-environmental measures, largely ignoring the potential of Internet-based businesses and services for rural job creation

    "Many" Chinas? The Economic Diversity of China's Provinces

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    This note analyzes China's provincial diversity from two perspectives. First, the regional gross domestic products of China's 31 mainland provinces are compared with the national GDP of other countries. This demonstrates that China's most advanced provinces and urban areas have per capita GDP levels comparable to those of Sweden and Singapore. On the other hand, China's least developed provinces have a standard of living similar to those of Sudan and Honduras. The second part of the analysis demonstrates that China's economic diversity is not unique. In fact, European countries exhibit almost the same degree of income diversity as do Chinese provinces. Copyright 2006 The Population Council, Inc..

    Anthropogenic Factors in Land-Use Change in China

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    Population momentum and the demand on land and water resources

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    Future world population growth is fuelled by two components: the demographic momentum, which is built into the age composition of current populations, and changes in reproductive behaviour and mortality of generations yet to come. This paper investigates, by major world regions and countries, what we know about population growth, what can be projected with reasonable certainty, and what is pure speculation. The exposition sets a frame for analysing demographic driving forces that are expected to increase human demand and pressures on land and water resources. These have been contrasted with current resource assessments of regional availability and use of land, in particular with estimates of remaining land with cultivation potential. In establishing a balance between availabilty of land resources and projected needs, the paper distinguishes regions with limited land and water resources and high population pressure from areas with abundant resources and low or moderate demographic demand. Overall, it is estimated that two-thirds of the remaining balance of land with rainfed cultivation potential is currently covered by various forest ecosystems and wetlands. The respective percentages by region vary between 23% in Southern Africa to 89% in South-Eastern Asia. For Latin America and Asia the estimated share of the balance of land with cultivation potential under forest and wetland ecosystems is about 70%, in Africa this is about 60%. If these were to be preserved, the remaining balance of land with some potential for rainfed crop cultivation would amount to some 550 million hectares. The regions which will experience the largest difficulties in meeting future demand for land resources and water, or alternatively have to cope with much increased dependency on external supplies, include foremost Western Asia, South-Central Asia, and Northern Africa. A large stress on resources is to be expected also in many countries of Eastern, Western and Southern Africa <br

    Innovative Rural Development Initiatives

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    this report. We will first take a closer look at the formal network called &quot;Visit Follo&quot
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