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91.
The aim was to assess the role that fetal bladder size has in the determination of fetal hydronephrosis. Forty-three fetuses were evaluated for fetal hydronephrosis in the second trimester of pregnancy. Anteroposterior measurements of the renal pelvis were obtained with a full bladder and again when the bladder emptied in each fetus. Statistical analysis was performed using the Spearman rank order correlation coefficient to assess the relationship between bladder status and renal dilation. The anteroposterior size of the fetal renal pelvis diminished from 6.8 ± 1.8 mm on a full bladder scan to 4.5 ± 1.6 mm when the bladder was emptied (P<0.001). Fifty-three per cent of the fetuses whose renal pelvic measurements were 5 mm or more on a full bladder scan had normal-appearing renal pelvises when their bladders emptied. The status of the fetal bladder should be considered when evaluating fetal hydronephrosis.  相似文献   
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Polycyclic musks, 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta[g]-2-benzopyran (HHCB) and 7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene (AHTN), are used as fragrance ingredients in numerous consumer products such as cleaning agents and personal care products. Studies have reported the widespread occurrence of these musks in surface waters and fish from western European countries. Nevertheless, little is known about their accumulation in humans and wildlife in the United States. In this study, we measured concentrations of HHCB and AHTN in human adipose fat collected from New York City. Furthermore, tissues from marine mammals, water birds, and fish collected from US waters were analyzed to determine the concentrations of HHCB and AHTN. Concentrations of HHCB and AHTN in human adipose fat samples ranged from 12 to 798 and from <5 to 134 ng/g, on a lipid weight basis, respectively. A significant correlation existed between the concentrations of HHCB and AHTN in human adipose fat. Concentrations of HHCB and AHTN were not positively correlated with age or gender of the donors. HHCB was found in tissues of several wildlife species, but not in the livers of polar bear from the Alaskan Arctic. Among wildlife species analyzed, spinner and bottlenose dolphins collected from Florida coastal waters contained measurable concentrations of HHCB.  相似文献   
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Sea ports and the related maritime activities (e.g. shipping, shipbuilding, etc.) are one of the main driver of Europe’s growth, jobs, competitiveness and prosperity. The continuously growth of shipping sectors has however introduced some environmental concerns, particularly with respect to ship-generated waste management. The port of Koper, one of the major ports on the northern Adriatic Coast, is the focus of this study. In this paper, a life cycle assessment was performed to identify and quantify the environmental impacts caused by the ship-generated waste management of port of Koper. Carcinogens substance (e.g. dioxins) and inorganic emissions, especially heavy metals, resulted to be the most critical environmental issues, while the fossil fuels consumption is reduced by recovery of ship-generated oils. Moreover, the final treatment of ship waste was found to be critical phase of the management, and the landfill have a significant contribute to the overall environmental load. These results can be useful in the identification of the best practices and in the implementation of waste management plans in ports.  相似文献   
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A fouling assemblage (including density, species richness and diversity, and biomass) growing on netting of fish farm cages was investigated in Stracinska Bay??Location 1 and Peles Bay??Location 2 (Croatia) in order to test the efficiency of fouling as a bioindicator of organic pollution. A total number of 40 algal taxa in Location 1 and total number of 22 algal taxa in Location 2 were identified, with a dominance of opportunistic species (ESG II). We found domination of algal species over animal species and absolute dominance of Rhodophyta which are typical fouler in the Adriatic Sea. Low diversity and species richness with increase in value of the R/P index (occasionally higher than 6) were recorded in Location 2, indicating a certain impact of nutrient enrichment from fish culture facilities on a fouling community structure.  相似文献   
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Stochastic transfer of information in a hierarchy of simulators is offered as a conceptual approach for assessing forest responses to changing climate and air quality across 13 southeastern states of the USA. This assessment approach combines geographic information system and Monte Carlo capabilities with several scales of computer modeling for southern pine species and eastern deciduous forests. Outputs, such as forest production, evapotranspiration and carbon pools, may be compared statistically for alternative equilibrium or transient scenarios providing a statistical basis for decision making in regional assessments. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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The migration behavior of the actinyl ions U(VI)O22+, Np(V)O2+ and Pu(V,VI)O2(+,2+) in the geosphere is to a large extend controlled by sorption reactions (inner- or outer-sphere adsorption, ion-exchange, coprecipitation/structural incorporation) with minerals. Here NpO2+ adsorption onto calcite is studied in batch type experiments over a wide range of pH (6.0–9.4) and concentration (0.4 μM–40 μM) conditions. pH is adjusted by variation of CO2 partial pressure. Adsorption is found to be pH dependent with maximal adsorption at pH 8.3 decreasing with increasing and decreasing pH. pH dependence of adsorption decreases with increasing Np(V) concentration. EXAFS data of neptunyl adsorbed to calcite and neptunyl in the supernatant shows differences in the Np(V)-O-yl distance, 1.85 ± 0.01 Å for the adsorbed and 1.82 ± 0.01 Å for the solution species. The equatorial environment of the neptunyl in solution shows about 5 oxygen neighbours at 2.45 ± 0.02 Å. For adsorbed neptunyl there are also about 5 oxygen neighbours at 2.46 ± 0.01 Å. An additional feature in the adsorbed species' R-space spectrum can be related to carbonate neighbours, 3 to 6 carbon backscatterers (C-eq) at 3.05 ± 0.03 Å and 3 to 6 oxygen backscatterers (O-eq2) at 3.31 ± 0.02 Å. The differences in the Np(V)-O-yl distance and the C-eq and O-eq2 backscatterers which are only present for the adsorbed species indicate inner-sphere bonding of the adsorbed neptunyl species to the calcite surface. Experiments on adsorption kinetics indicate that after a fast surface adsorption process a continuous slow uptake occurs which may be explained by incorporation via surface dissolution and reprecipitation processes. This is also indicated by the part irreversibility of the adsorption as shown by increased KD values after desorption compared to adsorption.  相似文献   
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