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The paper engages in the discussion of conducting research in war zones, initiated in Disasters by Barakat and Ellis. It looks specifically at possibilities for research in the war zones of Eritrea and Northern Ethiopia during the 1980s, and notes the ways in which this context differs from wars in the former Yugoslavia to which Barakat and Ellis mainly refer. The authors suggest that the unique context of every internal war, and the institutional actors that converge around this context, create both the potential and the demand for particular kinds of information, especially when humanitarian programmes involving international donors are under way. De-contexualising research in war zones from the specific context in which it occurs, in order to derive general guidelines, can thus be problematic.  相似文献   
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Mild pyelectasis     
Mild pyelectasis is a common finding which is often incidental, with no significant long term sequelae. However, there is a small association with aneuploidy and postnatal renal pathology. In this paper the aetiology and prognosis are discussed and the management strategies described. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
3.
Processes of xylem formation in Dahurian larch have been studied at three sites differing in the hydrothermal regime of soils in the permafrost zone of Middle Siberia. It has been found that the start and end dates of different phases of tree ring formation may differ between the sites by up to 14 days, depending on site conditions. The data obtained contribute to knowledge of possible changes in larch forest phytomass production and provide the possibility of predicting its dynamics under conditions of climate change.  相似文献   
4.
On the basis of the recently estimated emission inventory for East Asia with a resolution of 1×1°, the transport and chemical transformation of sulfur compounds over East Asia during the period of 22 February through 4 May 2001 was investigated by using the Models-3 Community Multi-scale Air Quality (CMAQ) modeling system with meteorological fields calculated by the regional atmospheric modeling system (RAMS). For evaluating the model performance simulated concentrations of sulfur dioxide (SO2) and aerosol sulfate (SO42−) were compared with the observations on the ground level at four remote sites in Japan and on board aircraft and vessel during the transport and chemical evolution over the Pacific and Asian Pacific regional aerosol characterization experiment field campaigns, and it was found that the model reproduces many of the important features in the observations, including horizontal and vertical gradients. The SO2 and SO42− concentrations show pronounced variations in time and space, with SO2 and SO42− behaving differently due to the interplay of chemical conversion, removal and transport processes. Analysis of model results shows that emission was the dominant term in regulating the SO2 spatial distribution, while conversion of SO2 to SO42− in the gas phase and the aqueous phase and wet removal were the primary factors that controlled SO42− amounts. The gas phase and the aqueous phase have the same importance in oxidizing SO2, and about 42% sulfur compounds (25% in SO2) emitted in the model domain was transported out, while about 57% (35% by wet removal processes) was deposited in the domain during the study period.  相似文献   
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This paper describes a new approach that allows us to partition the anthropogenic and natural contributions to heavy metal accumulations in roadside agricultural soils. This approach, combining trend analysis and multivariate statistical analysis, partitions total heavy metals into three components: anthropogenic, natural, and unexplained residual. The approach was applied in a case study in Yixing City, China, to determine the spatial distributions of heavy metal accumulations. The results show that anthropogenic components of Pb, Cu, Zn, and Cd account for 52.4%, 23.04%, 5.09%, and 10.9% of total content, respectively. Spatial distributions of anthropogenic components are characterized by decreasing accumulation with increasing distance from the road. Ranges of influence of traffic for Pb, Cu, and Cd are beyond 300 m, whereas the range of Zn is less than 200 m. The spatial distributions of the four elements?? natural components show relatively similar distribution patterns. Assessments of variable partition methods show that the predicted values of Pb, Cu, Zn, and Cd are consistent with their measured values. The anthropogenic components extracted from total contents of heavy metal will be useful for modeling heavy metal accumulations produced by human activities.  相似文献   
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Understanding the dynamics of population recovery is particularly complex when an organism has multiple, remote breeding and feeding grounds separated by one of the longest known migration routes. This study reports on the most comprehensive assessment of humpback whale (Megaptera novaeangliae) movements between remote Antarctic waters south of New Zealand and east Australia (EA), and the migratory corridors and breeding grounds of Australia and Oceania. A total of 112 individual whales were identified; 57 from microsatellites and 61 by fluke with 23 % (n = 26) matched to sites outside Antarctica. Despite large datasets from other southern regions being included in the comparison, the whales were predominantly linked to EA (n = 24). Only two matches to the Oceania catalogues directly north was surprising; therefore the primary feeding grounds of these endangered whales still remain unknown. The confirmation of the Balleny Islands as an important feeding ground for EA whales could provide an insight into reasons behind the rapid recovery of this population. Determining the feeding grounds of Oceania’s whales may explain whether prey energetics or migration length are limiting factors to their recovery and will allow an understanding of future ecosystem changes in these whales.  相似文献   
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