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71.
The question whether the possibility exists of transmission of HIV by hematophagous insects from infected to uninfected persons is a point of very intensive discussion. The solution of this problem could help to explain the spreading of the disease in human populations and could contribute to an understanding of the evolution of AIDS and the possible transfer from wild primates into human populations. The classical routes of pathogen transmission by blood-sucking arthropods are either "mechanical" or "biological". Both ways are rejected, the latter since no replication of the retro-virus in the vector exists and its survival in the arthropod is very limited. Based on long experimental experience with biting flies as well as with plant-sucking insects a third hitherto neglected way of transmission by regurgitation of gut content can be introduced. Since regurgitation is neither "mechanical" nor "biological", "regurgitative transmission" must be introduced as an additional term.  相似文献   
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Wir danken Dr. Kerndorff für die kritische Durchsicht des Manuskripts.  相似文献   
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Mitigation and adaptation synergy in forest sector   总被引:1,自引:1,他引:1  
Mitigation and adaptation are the two main strategies to address climate change. Mitigation and adaptation have been considered separately in the global negotiations as well as literature. There is a realization on the need to explore and promote synergy between mitigation and adaptation while addressing climate change. In this paper, an attempt is made to explore the synergy between mitigation and adaptation by considering forest sector, which on the one hand is projected to be adversely impacted under the projected climate change scenarios and on the other provide opportunities to mitigate climate change. Thus, the potential and need for incorporating adaptation strategies and practices in mitigation projects is presented with a few examples. Firstly, there is a need to ensure that mitigation programs or projects do not increase the vulnerability of forest ecosystems and plantations. Secondly, several adaptation practices could be incorporated into mitigation projects to reduce vulnerability. Further, many of the mitigation projects indeed reduce vulnerability and promote adaptation, for example; forest and biodiversity conservation, protected area management and sustainable forestry. Also, many adaptation options such as urban forestry, soil and water conservation and drought resistant varieties also contribute to mitigation of climate change. Thus, there is need for research and field demonstration of synergy between mitigation and adaptation, so that the cost of addressing climate change impacts can be reduced and co-benefits increased.  相似文献   
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Ten out of the 12 new EU members, used to belong to the so-called “former eastern block”, with a post WWII environmental policy radically different from the tendencies followed in Western Europe. The lack of conservation regulations has resulted in a rather harmful industrialization, regarding natural resources and environmental quality. While air pollution transfer is a phenomenon of transboundary level, there is a particular interest in examining the contribution of the new EU member states to the environmental pressure faced by the older member states and vice versa. The current study utilises the official data for almost 20 years published by the European Monitoring and Evaluation Program concerning the transboundary transfer of NOx and SO2 in order to analyse the situation and discuss the present and future environmental policy regarding air pollution.  相似文献   
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