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121.
122.
Previous work has demonstrated that plant uptake of radiocaesium (RCs) is related to the activity concentration of RCs in soil solution, which is linked to the soil/soil solution distribution coefficient, K(D). The solid-liquid distribution of RCs is generally studied in soil suspensions in the laboratory and there are few reported measurements for in situ soil solutions. From a data set of 53 different soils (contaminated with either 134CsCl or 137CsCl) used in pot trials to investigate grass uptake of RCs, we analysed the variation of in situ K(D) with measured soil properties. The soils differed widely in % clay (0.5-58%), organic matter content (1.9-96%) and pH (2.4-7.0, CaCl2). The K(D) varied between 29 and 375,000 L kg-' (median 1460 L kg(-1)). Stepwise multiple regression analysis showed a significant correlation between the log K(D) and pH (p < 0.001), log %clay (p < 0.01) and log exchangeable K (p < 0.001) (overall R2 = 0.70). The in situ K(D) values were further compared to K(D)S predicted using an existing model, which assumes that RCs sorption occurs on specific sites and regular ion-exchange sites on the soil solid phase. Sorption of RCs on specific sites was quantified from the radiocaesium interception potential (RIP) measured for each soil and the soil solution concentrations of K+ and NH4+. The in situ log K(D) correlated well with the predicted K(D) (R2 = 0.85 before plant growth, R2 = 0.83 after plant growth). However, the observations were fivefold to eightfold higher than the predictions, particularly for the mineral soils. We attribute the under-prediction to the long contact times (minimum 4 weeks) between the RCs tracers and our experimental soils relative to the short (24 h) contact times used in RIP measurements. We conclude that our data confirmed the model but that ageing of RCs in soil is a factor that needs to be considered to better predict in situ KD values.  相似文献   
123.
Although Dutch cities were among the forerunners in local climate policy, a systematic overview on climate mitigation and adaptation policy is still missing. This study aims to fill this gap by analysing 25 Dutch cities using indicators for the level of anchoring in policy, organisation and practical implementation as well as multi-level relations. Since Tilburg, Amsterdam, Den Haag and Rotterdam show a higher performance than other Dutch cities, these four cities are used as reference cities. The findings suggest that structural integration of climate mitigation and adaptation is limited in Dutch cities. The study points at three recent trends in local climate governance in the Netherlands: (i) decentralisation within municipal organisations, (ii) externalisation initiatives that place climate policy outside the municipal organisation and (iii) regionalisation with neighbouring municipalities and the provincial government.  相似文献   
124.

Objective

We performed a 1-year evaluation of a novel strategy of simultaneously analyzing single nucleotide variants (SNVs), copy number variants (CNVs) and copy-number-neutral Absence-of-Heterozygosity from Whole Exome Sequencing (WES) data for prenatal diagnosis of fetuses with ultrasound (US) anomalies and a non-causative QF-PCR result.

Methods

After invasive diagnostics, whole exome parent-offspring trio-sequencing with exome-wide CNV analysis was performed in pregnancies with fetal US anomalies and a non-causative QF-PCR result (WES-CNV). On request, additional SNV-analysis, restricted to (the) requested gene panel(s) only (with the option of whole exome SNV-analysis afterward) was performed simultaneously (WES-CNV/SNV) or as rapid SNV-re-analysis, following a normal CNV analysis.

Results

In total, 415 prenatal samples were included. Following a non-causative QF-PCR result, WES-CNV analysis was initially requested for 74.3% of the chorionic villus (CV) samples and 45% of the amniotic fluid (AF) samples. In case WES-CNV analysis did not reveal a causative aberration, SNV-re-analysis was requested in 41.7% of the CV samples and 17.5% of the AF samples. All initial analyses could be finished within 2 weeks after sampling. For SNV-re-analysis during pregnancy, turn-around-times (TATs) varied between one and 8 days.

Conclusion

We show a highly efficient all-in-one WES-based strategy, with short TATs, and the option of rapid SNV-re-analysis after a normal CNV result.  相似文献   
125.
Prenatal trio exome sequencing (ES) has become integrated into the care for pregnant women when the fetus has structural anomalies. Details regarding optimizing indications for prenatal exome sequencing, its detection rates with different categories of fetal anomalies, and principles of interpretation of pathogenicity of sequence variants are still under investigation. However, there is now growing consensus about its benefits for finding the cause of fetal structural anomalies. What is not established, is whether exome or genome sequencing (GS) has a place in the care of all pregnant women. This report is a summary of the debate on this topic at the 26th International Conference on Prenatal Diagnosis and Therapy. Both expert debaters considered the advantages and disadvantages. Advantages include the ability to diagnose serious childhood conditions without a prenatally observable phenotype, which creates the potential of early treatments. Disadvantages include difficulties with variant classification, counseling complexities, healthcare cost, and the burden on healthcare systems and families, in particular with the discovery of adult-onset disorders or variants of uncertain significance. Although both debaters weighed the balance of these conflicting arguments differently, they agreed that more research is needed to further explore the clinical utility and ethical aspects of GS for all pregnant women.  相似文献   
126.
Lindane (??-hexachlorocyclohexane, ??-HCH) is a recalcitrant and toxic organochlorine insecticide. Due to its non-selective production process and widespread use, HCH isomers and their degradation products have been detected frequently in soils and groundwater. An innovative technology using microbial produced Pd(0) nanoparticles, i.e. bio-Pd, was developed to treat groundwater containing a mixture of HCHs and chlorobenzenes. In a first step, the groundwater was de-ironized and most of the chlorobenzenes were removed in a biological trickling filter. The ??g?L?1 levels of HCHs and chlorobenzenes were removed in a second step by the bio-Pd-based technology. Therefore, a 200-L pilot scale reactor was developed with 100?mg?L?1 bio-Pd encapsulated in alginate beads. Hydrogen gas was bubbled at the bottom of the reactor and served to charge the bio-Pd catalyst. The reactor influent contained 5.2???g?L?1 HCHs and 51.1???g?L?1 chlorobenzenes. During a test period of 10?days, 29% of the HCH isomers and 63% of the chlorobenzenes were removed applying a nominal hydraulic residence time of 4?h. These removal percentages could be increased to 75 and 68% by doubling the nominal hydraulic residence time to 8?h. This study demonstrated that biologically produced nanoparticles of Pd can be applied for the large-scale remediation of groundwater contaminated with HCHs.  相似文献   
127.
Recent evidence shows that the frequently proclaimed collapse of the traditional career model is actually not supported by job tenure data. This paper argues that the observed stability of job tenure might be explained by an increasing number of shamrock organizations. This organizational form has three types of workers: core employees, professional freelancers, and routine workers. In such an organization, two very different career models coexist. The organization largely determines the career of the core employee, whereas the individual essentially shapes that of the professional freelancer. This paper studies extensively the career of this second group: the professional freelancer, a growing phenomenon in many developed countries but not yet the focus of many career studies. We develop a freelance career success model on basis of the intelligent career framework augmented by insights from literature on entrepreneurship. Data are from a web survey with responses from about 1600 independent professionals in the Netherlands, in combination with 51 in‐depth interviews. We provide two main contributions. First, we report findings from the first large‐scale quantitative study into freelance career success. Second, this study enhances our understanding of the success of the modern career by building bridges between career and entrepreneurship literatures. We conclude that the external environment in which an individual freelancer operates is the most important factor determining career success. The study therefore suggests that more work needs to be performed on the relationship between the environment and individual career success. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
128.
The adverse impacts of climate change are widely recognized as well as the importance of the mitigation of carbon dioxide (CO2). Battery driven vehicles are expected to have a bright future, since GHG emissions can be reduced. Lithium-ion (Li-ion) batteries appear to be the most promising, due to their high energy density. Recently, the discussion concerning adequate lithium carbonate (Li2CO3) resources is resolved. The current challenge is the needed increase in flow rate of Li2CO3 into society to foresee in forecasted demand. This research determines ten factors which influence the availability of Li-ion batteries for the EU27 in the coming decades. They are used in a system dynamics analysis. The results of this research show that undersupply can be expected in the EU27 until 2045 somewhere between 0.5 Mt and 2.8 Mt. Substitution of Li2CO3 in other end-use markets and recycling can relieve the strain on Li2CO3 supply to some extent. In 2050, 20% of the vehicle fleet in the EU27 can be battery electric vehicles (BEVs). The lack of resources in the EU27 and the geographical distribution of lithium in politically sensitive areas suggest that the shares of lithium available for the EU27 will be less than assumed in this research. The increase in flow rate shows to be the bottle-neck for a transition to (partly) battery driven vehicles in the EU27, at least when Li-ion batteries are used. Focusing on large-scale application of BEVs with Li-ion batteries in order to substantially mitigate CO2 emissions in transport is a futile campaign.  相似文献   
129.
Not much is known about lay public perceptions of non-native species and their underlying values. Public awareness and engagement, however, are important aspects in invasive species management. In this study, we examined the relations between the lay public’s visions of nature, their knowledge about non-native species, and their perceptions of non-native species and invasive species management with a survey administered in the Netherlands. Within this framework, we identified three measures for perception of non-native species: perceived risk, control and engagement. In general, respondents scored moderate values for perceived risk and personal engagement. However, in case of potential ecological or human health risks, control measures were supported. Respondents’ images of the human–nature relationship proved to be relevant in engagement in problems caused by invasive species and in recognizing the need for control, while images of nature appeared to be most important in perceiving risks to the environment. We also found that eradication of non-native species was predominantly opposed for species with a high cuddliness factor such as mammals and bird species. We conclude that lay public perceptions of non-native species have to be put in a wider context of visions of nature, and we discuss the implications for public support for invasive species management.  相似文献   
130.
Moving towards a more sustainable adaptation process requires closer integration of policies related to the environment. An important actor in this is the local government. This paper examines to what extend adaptation is currently being integrated into Dutch local policies, and what the role is of a municipality's size, risk and experience in the encountered manifestations of adaptation. First, it was determined that adaptations taking place only anticipate currently perceivable weather extremes – mostly increasing precipitation. Second, it was determined that the realisation of further adaptations is hindered by a strongly sectoral divided reality. Adaptation is now heavily dominated by the water department, while spatial planning and the environment are only limitedly involved. Finally, it was observed that the contextual factor size proved to most important for horizontal policy integration, whereas the contextual factor extreme-weather experience was the most definite for the realisation of adaptations. We conclude that a more sustainable adaptation should first tackle the sectoral divides which requires administrative efforts, for example, professional training. These would preferably be initiated from a vertical direction.  相似文献   
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