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61.
Methane exchange with the atmosphere was measured during three seasons at the Rooney Road landfill in Jefferson County, CO. Substantial spatial and temporal variability in exchange rates were observed. Mean fluxes to the atmosphere were 534, 1290, and 538 mg CH4/m2/day, respectively, in the fall of 1994, winter of 1994-1995, and summer of 1995. Median fluxes were 12.42, 8.62, and 5.65 mg CH4/m2/day, respectively, during those seasons. Forty-three of 177 measurements had small negative fluxes, suggesting methanotrophic activity in the landfill cover soils. Despite probable methanotrophic activity in cover soils, landfills without gas collection systems may emit substantial CH4 to the atmosphere, with large spatial and seasonal variability.  相似文献   
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Salinization and sodicity are obstacles for vegetation reconstruction of coastal tidal flat soils. A study was conducted with flue gas desulfurization(FGD)-gypsum applied at rates of 0, 15, 30, 45 and 60 Mg/ha to remediate tidal flat soils of the Yangtze River estuary.Exchangeable sodium percentage(ESP), exchangeable sodium(ExNa), p H, soluble salt concentration, and composition of soluble salts were measured in 10 cm increments from the surface to 30 cm depth after 6 and 18 months. The results indicated that the effect of FGD-gypsum is greatest in the 0–10 cm mixing soil layer and 60 Mg/ha was the optimal rate that can reduce the ESP to below 6% and decrease soil p H to neutral(7.0). The improvement effect was reached after 6 months, and remained after 18 months. The composition of soluble salts was transformed from sodic salt ions mainly containing Na~+, HCO_3~-+ CO_3~(2-)and Cl-to neutral salt ions mainly containing Ca~(2+)and SO_4~(2-). Non-halophyte plants were survived at 90%. The study demonstrates that the use of FGD-gypsum for remediating tidal flat soils is promising.  相似文献   
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Fetal and neonatal alloimmune thrombocytopenia (FNAIT) is a potentially devastating condition, which may lead to intracranial haemorrhage (ICH) in the fetus or neonate, often with death or major neurological damage as consequence. In the absence of screening, preventive measures are only possible in the next pregnancy of women with an affected child. Controversy exists on the best intervention to minimise the risk of ICH. Most centres have abandoned treatment with serial fetal blood sampling (FBS) and platelet transfusions, because of a high rate of complications and the availability of quite effective non-invasive alternatives. In pregnancies with FNAIT and a previous affected child without ICH, weekly intravenous administration of immunoglobulins to the mother appears close to 100% effective to prevent fetal or neonatal ICH. Some centres add prednisone; this combination leads to slightly higher platelet counts at birth. In pregnant women with a previous child with ICH, the recurrence risk seems particularly high, and more aggressive maternal medical treatment is recommended, starting earlier with immunoglobulins. Whether a higher intravenous immunoglobulin dose or the addition of prednisone is really necessary is unclear. What does seem to be clear is that the use of FBS should be minimised, possibly even abandoned completely. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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Potential health risks of exposure to emissions of a yeast and penicillin production plant were investigated by measuring viable particles and protein contents of particles in ambient air. The results showed a clear decrease of the downwind number of yeast colonyforming units with increasing distance from the source. Upwind the number of yeast colony-forming units was zero. Identification showed that nearly all yeast were of the species Saccharomlces cerevisiae. Such a trend could not be found for the total number of colony-forming units (yeasts, molds, and bacteria) although the upwind concentration was slightly lower than the downwind concentration. The downwind protein concentration was significantly elevated compared to the upwind concentration.  相似文献   
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The relationship among sugar concentrations, microbial community and physical variables (precipitation and soil temperature) was investigated in a ryegrass soil from January 2004 to January 2005. Mono- and disaccharide sugars were extracted using a mixture of dichloromethane and methanol and analyzed as their TMS derivatives by GC-MS. Changes in microbial community were assessed using phospholipid and neutral lipid fatty acids (PLFA and NLFA, respectively) analysis. The results of a one-year study showed that the seasonal variability of sugar contents found in the soil samples is mainly related to biomass or nutritional status of the fungal community. The increase in sucrose and fructose exudation by plant roots in the beginning of the growing season (early spring) may be responsible for the highest fungal biomass amount (PLFAs) observed in this study. Fungal storage lipid abundances (NLFAs) peaked in summer, during the same period that the highest concentrations of mannitol and trehalose were detected. This is consistent with these two sugars being stress-induced fungal metabolites, produced due to the low soil moisture observed during this season. In contrast, bacterial community growth seems to be more dependent on plant substrate than on physical variables, since the strongest decrease in bacterial biomass amounts (PLFAs) was found after cutting of the ryegrass field in early July.  相似文献   
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Perinatal survival rates after intrauterine transfusions (IUT) for red cell alloimmunisation now exceed 90%, which demonstrates the safety and efficacy of one of the most successful procedures in fetal therapy. However, improved perinatal survival could lead to an increased number of children with long-term disabilities. The importance of long-term follow-up studies in fetal therapy lies in both the necessity of evaluation of antenatal management as well as in evidence-based preconceptional and prenatal counselling. This review describes the possible long-term cardiovascular and neurodevelopmental sequelae after IUT treatment for different indications including red cell alloimmunisation, parvovirus B19 infection, fetomaternal haemorrhage and twin anaemia-polycythaemia sequence. © 2013 John Wiley & Sons, Ltd.  相似文献   
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