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A method, based on XAD-8 resin sorbtion and Particle Induced X-ray Emission (PIXE), was developed for Total Organic Chlorine (TOCl) determinations. The method was applied to recipient waters of a kraft bleach plant, and the determined TOCl values compared with other parameters. The detection limit was about 10 μg/l.  相似文献   
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This study has investigated and outlined the possible quantification and mapping of the distributions of advective solute travel times through hydrological catchments. These distributions are essential for understanding how local water flow and solute transport and attenuation processes affect the catchment-scale transport of solute, for instance with regard to biogeochemical cycling, contamination persistence and water quality. The spatial and statistical distributions of advective travel times have been quantified based on reported hydrological flow and mass-transport modeling results for two coastal Swedish catchments. The results show that the combined travel time distributions for the groundwater-stream network continuum in these catchments depend largely on the groundwater system and model representation, in particular regarding the spatial variability of groundwater hydraulic parameters (conductivity, porosity and gradient), and the possible contributions of slower/deeper groundwater flow components. Model assumptions about the spatial variability of groundwater hydraulic properties can thus greatly affect model results of catchment-scale solute spreading. The importance of advective travel time variability for the total mass delivery of naturally attenuated solute (tracer, nutrient, pollutant) from a catchment to its downstream water recipient depends on the product of catchment-average physical travel time and attenuation rate.  相似文献   
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Multi-national statistics are frequently based on data, whichoriginate from national surveys. The systems of nomenclatureapplied for key attributes often show national differences.Different error sources which are incorporated in multi-nationalstatistics are discussed. The paper presents approaches forharmonisation and standardisation of multi-nationalenvironmental statistics and gives examples from the forestrysector. The effect of differences of national forest areaestimates on multi-national figures is quantified. An examplefrom forest health surveys is presented that shows the impact ofdifferent interpretation and application of the attribute crown transparency that is already harmonised on theEuropean level.  相似文献   
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The EU-water framework directive aims at nutrient reductions, since anthropogenically induced eutrophication is a major threat for coastal waters. However, phytoplankton biomass in southern Baltic Sea coastal water bodies (CWB) remains high and the underlying mechanisms are not well understood. Therefore, a CWB data set was analysed regarding changes in phytoplankton biomass and nutrient concentration of nitrogen (N) and phosphorus (P) from 2000 to 2014. It was expected to find imbalances between produced phytoplankton biomass and total nutrient concentrations. Inner CWB were cyanobacteria-dominated and showed up to five times higher chlorophyll a-concentrations compared to outer CWB with similar total phosphorus-concentrations. Phytoplankton tended to be P-limited during spring and N-limited during summer. Phytoplankton biomass and nutrient concentrations were even higher during very humid years, which indicated a close coupling of the CWB with their catchment areas. This study suggests that re-mesotrophication efforts need to consider the importance of changed phytoplankton composition and nutrient availabilities.  相似文献   
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Objective

In this retrospective study, we describe the clinical course, ultrasound findings and genetic investigations of fetuses affected by fetal akinesia.

Materials and Methods

We enrolled 22 eukaryotic fetuses of 18 families, diagnosed with fetal akinesia between 2008 and 2016 at the Department of Obstetrics and Feto-Maternal Medicine at the Medical University of Vienna. Routine genetic evaluation included karyotyping and chromosomal microarray analysis. Retrospectively, exome sequencing was performed in the index case of 11 families, if stored DNA was available. Confirmation analyses and genetic diagnosis of siblings were performed by using Sanger sequencing.

Results

Whole exome sequencing identified pathogenic variants of CNTN1, RYR1, NEB, GLDN, HRAS and TNNT3 in six cases of 11 families. In three of these families, the variants were confirmed in the respective sibling.

Conclusions

The present study demonstrates a high diagnostic yield of exome sequencing in fetuses affected by akinesia syndrome, especially if family history is positive. Still, in a large part the underlying genetic cause remained unknown, whereas precise clinical evaluation in combination with exome sequencing shows to be the best tool to find the disease causing variants.  相似文献   
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A loamy soil contaminated with 137CsCl 40 years ago was investigated by a sequential extraction technique to determine the effect of ageing on chemical availability of 137Cs. The soil samples were sequentially extracted with H2O, NH4Ac, NH2OH·HCl, H2O2, and HNO3. Extractability of 137Cs decreased in the order: HNO3 > Residual > H2O2 > NH4Ac > NH2OH·HCl > H2O. Only 0.94% in labile fractions (H2O and NH4Ac), while more than 96% was found in the strongly bound fraction (HNO3 and residual). However, the activity percentage in labile fractions was increased to 1.34% after autoclaving treatment, while those in the other fractions did not significantly differ. This indicates that the microbial activity played a role in the 137Cs retention. In the subsequent pot experiments with ryegrass and leek, specific activities in both plants were significantly higher in autoclaved soil than in non-autoclaved soil, and uptake of 137Cs in the five cuts by ryegrass was 25% of the labile 137Cs in the soil. In addition, a positive correlation was found between the amount of 137Cs in labile fractions and that by plant uptake.  相似文献   
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