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991.
This paper describes a European wide assessment of element budgets, using available data on deposition, meteorology and soil solution chemistry at 121 Intensive Monitoring plots. Input fluxes from the atmosphere were derived from fortnightly or monthly measurements of bulk deposition and throughfall, corrected for canopy uptake. Element outputs from the forest ecosystem were derived by multiplying fortnightly or monthly measurements of the soil solution composition at the bottom of the root zone with simulated unsaturated soil water fluxes. Despite the uncertainties in the calculated budgets, the results indicate that: (i) SO4 is still the dominant source of actual soil acidification despite the generally lower input of S than N, due to the different behaviour of S (near tracer) and N (strong retention); (ii) base cation removal due to man-induced soil acidification is limited; and (iii) Al release is high in areas with high S inputs and low base status.  相似文献   
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993.
In this article, we review the virology, pathology, epidemiology and clinical spectrum of intrauterine human parvovirus B19 (B19V) infection, including intrauterine fetal death, non-immune hydrops fetalis, thrombocytopenia and neurological manifestations such as pediatric stroke and perivascular calcifications. In addition, we discuss the new insights into the neurodevelopmental outcome of intrauterine B19V infection. Current diagnosis and management of B19V infection is summarized, including a diagnostic and follow-up flowchart for practical clinical use. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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As part of a longitudinal cohort study, now in its second decade, we determined PCDDs/Fs dl-PCBs and PBDEs in serum of adolescents with known perinatal PCDD/F exposure. Of the original cohort, 33 adolescents aged 14-19 years, who had been studied previously during their neonatal (n=60), toddler and pre-pubertal period (n=41) agreed to participate in the current follow-up. PCDD/F-, dl-PCB- and PBDE congeners were measured using GC/MS. Current serum levels of PCDD/Fs determined in our cohort were relatively low (mean of 2.2pg/g) compared to the perinatal exposure. No correlation between perinatal exposure and current serum PCDD/F was found. Planar PCB TEQ levels were 2.2pg/g. Current summation operatorPBDE levels were 8.7ng/g lipid. There was one outlier with a summation operatorPBDE of 74ng/g lipid. The presence of this high value indicates that the exposure pathway is different from PCDD/F and PCB, most likely by dust and food contaminated with dust. Concluding we can say that current PCDD/F levels are quite low compared to the perinatal PCDD/F exposure of the cohort. PBDE levels however are relatively high compared to other European countries, more research on possible health effects of these levels, especially for subjects with outlier concentrations, should be performed.  相似文献   
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Humble leadership is attracting increased scholarly attention, but little is known about its effects when used in conjunction with less humble leadership behaviors that rely on a perception of the leader as confident and charismatic. This study contrasts the effects on top management team (TMT) potency and organizational performance of a more humble (feedback seeking) and a less humble (vision) CEO leader behavior. We hypothesize that CEO feedback seeking increases TMT potency and firm performance by communicating to TMT members that the organization values their input and encouraging their own feedback seeking, whereas CEO vision articulation influences these outcomes by fostering greater clarity about the firm's direction, and an enhanced ability to coordinate efforts within the TMT. CEOs who have not developed a vision can achieve a similar positive impact on TMT potency and firm performance by seeking feedback. In a sample of CEOs and TMT members from 65 firms, both CEO feedback seeking and vision articulation exhibit positive direct relationships with firm performance. However, only feedback seeking displays an indirect effect on performance via TMT potency. Finally, CEO feedback seeking has its strongest effects on firm performance and TMT potency for CEOs who are not seen as having a vision.  相似文献   
998.
Environmental Science and Pollution Research - Due to the complexity and variability of textile wastewater composition, a constant search for new treatment strategies that are efficient,...  相似文献   
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