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51.
Previous studies of upland roadside soils in Cumbria, that would normally be naturally acidic, have highlighted that (a) runoff from roads subjected to long-term road salting can dramatically raise soil pH down slope in upland areas; (b) the soil pH increase dramatically changes N cycling in soils down slope, increasing mineralisation of organic matter, ammonification, ammonium leaching down slope and nitrification and nitrate leaching; (c) the increase in nitrification substantially increases nitrate leaching to down-slope rivers, and this is readily detectable in field studies; and (d) loss of soil organic matter over decades of salting is so great that organic matter is no longer substantially solubilised by high salt concentrations found in soil solution below road drains. This paper tests and supports the hypothesis that such effects are minimal for more calcareous soil ecosystems. It examines the soil and soil solution chemistry on another Cumbrian upland highway, the A686 near Leadgate, Alston. Sodium % of soil CEC values for soil transects affected by spray containing road salt are similar at both the A6 and A686 sites. However, spatial trends in calcium, magnesium, ammonium, and nitrate concentrations as well as pH differ, as a direct result of the higher weathering rate of parent material and possibly also the presence of limestone walls above both spray-affected and control transects at the A686 site.  相似文献   
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We report a multiplex family with a GATA1 gene mutation responsible for a massive fetal cerebral hemorrhage occurring at 36 weeks. Two other stillbirth cousins presented with fetal hydrops and congenital hemochromatosis' phenotype at 37 and 12 weeks of gestation. Molecular screening revealed the presence of a c.613G>A pathogenic allelic variation in exon 4 of GATA1 gene in the 3 male siblings and their carrier mothers. The diagnosis of a GATA1 gene mutation may be suspected in cases of male fetuses with intracerebral bleeding, particularly if a history of prior fetal loss(es) and mild maternal thrombocytopenia are also present.  相似文献   
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This article aims to explore a new approach to assess company decision systems regarding sustainability-related communication and decision support between senior management and product development levels. The assessment approach was developed in theory and its applicability was directly tested in action research in two small and medium-sized companies and two large companies. The results were validated against experiences made by two management consultancies. Our study indicates that successful companies should: (i) integrate sustainability into business goals and plans, backed up by suitable (ii) internal incentives and disincentives and (iii) decision support tools. Our study also indicates that the new assessment approach can be used as a template to assess the current state of sustainability integration in company decision systems.  相似文献   
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The influence of chemical initial conditions and chemical lateral boundary conditions (CLBCs) on long-term regional air quality model simulations was investigated using outputs from an annual simulation of the year 2002 on a North American domain. This simulation was carried out using the AURAMS regional air quality model. It was subdivided into three multi-month segments with two overlap periods (May 15–30 and September 1–30) to allow the segments to be run in parallel. For this approach to work, model predictions had to match very closely by the end of the two-week and four-week overlap periods. The time required for the values of daily domain-average surface PM2.5 concentration to match for the two simulation segments associated with each of the two overlap periods was four and six days, respectively. For individual locations within the model domain, however, the required spin-up period was as much as nine days, considerably longer than the 2–4-day spin-up period usually assumed in the literature. For ozone, on the other hand, the daily domain-average surface ozone concentration values did not converge for either overlap period. A zero-gradient CLBC had been used for all run segments and species. When a time-invariant CLBC for ozone was used instead, the daily domain-average surface ozone concentration values behaved more realistically and did converge after fewer than three days. A similar improvement was also obtained for individual locations, but with spin-up periods of up to nine days. Model chemical spin-up time thus seems to be dependent on the species considered, the time required for the influence of the inflow boundaries to reach all locations within the domain, and the impact of local emissions sources. These results suggest the use of a spin-up period of longer than one week for a large (continental) domain and long-term simulation of PM2.5 and O3 rather than the 2–4 days commonly assumed in the literature.  相似文献   
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