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Cristina Zago Gabriele Capodaglio Carlo Barbante Michele Giani Ivo Moret Giuseppe Scarponi Paolo Cescon 《Chemistry and Ecology》2002,18(1):39-51
In the present study the concentrations of cobalt, copper, iron, manganese, zinc were analysed and the speciation of copper and zinc performed, with a summer and winter sampling, for two areas in the Northern Adriatic Sea and crossing at the farthest zones of the Po river-sea water interface. Results show that when salinity increases the concentrations of all investigated metals (with the exception of cobalt) present some degree of biogeochemical cycling. Copper is the element whose dissolved phase has the highest importance in metal transport across the salinity gradient. Results of speciation analysis demonstrate that the presence of excess amounts (5-8 fold) of unbound ligands confers a buffering capacity for potential inputs of dissolved metals into the Northern Adriatic Sea. The speciation of both copper and zinc in the dissolved phase was dominated by organic complexation. 相似文献
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Ivo C. Bobsien Wolfgang Hukriede Christian Schlamkow Ren Friedland Norman Dreier Philipp R. Schubert Rolf Karez Thorsten B. H. Reusch 《Ambio》2021,50(2):400
For many coastal areas including the Baltic Sea, ambitious nutrient abatement goals have been set to curb eutrophication, but benefits of such measures were normally not studied in light of anticipated climate change. To project the likely responses of nutrient abatement on eelgrass (Zostera marina), we coupled a species distribution model with a biogeochemical model, obtaining future water turbidity, and a wave model for predicting the future hydrodynamics in the coastal area. Using this, eelgrass distribution was modeled for different combinations of nutrient scenarios and future wind fields. We are the first to demonstrate that while under a business as usual scenario overall eelgrass area will not recover, nutrient reductions that fulfill the Helsinki Commission’s Baltic Sea Action Plan (BSAP) are likely to lead to a substantial areal expansion of eelgrass coverage, primarily at the current distribution’s lower depth limits, thereby overcompensating losses in shallow areas caused by a stormier climate. 相似文献
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Fenjuan Wang Francesca Costabile Fenglei Liu Weimin Hong Dong Fang Ivo Allegrini 《Environmental monitoring and assessment》2010,168(1-4):21-31
Within the Sino-Italian environmental protection cooperation framework established in 2002, a comprehensive air quality monitoring network has been developed in urban Suzhou, a medium-sized Chinese city, in compliance with European standards (Directive 96/62/EC). This paper is among the first attempts to present a systematic and scientific analysis of benzene, toluene, and xylenes (BTX) pollution in China. It presents our analysis of BTX space-related and time-related measurement results. Background BTX concentrations were investigated by passive sampler Analyst® in 2003. We depicted the spatial distribution of average BTX concentrations collected from three 15-day campaigns on isoconcentration maps. This is the first time such detailed BTX concentration maps have been developed in China in a city scale. Continuous measurement of BTX by automatic gas chromatography was carried out at two fixed monitoring stations, one in an urban residential zone and one in a heavy traffic zone, from April to December 2005. The results show similar seasonal trends at both sites, the similarities reaching their greatest level in December and their lowest level in August. The average daily profile of BTX shows greater fluctuation in spring and winter with clear morning and evening peaks. Daily average benzene, toluene, and m,p-xylenes concentrations for the study period were 2.64, 11.52, and 3.52 μg m???3, respectively. The benzene/toluene ratio we found was lower in Suzhou than those published in studies of other worldwide cities, which indicates serious levels of toluene pollution from local stationary sources. The similarities in seasonal trend and spatial distribution in these manual and automatic measurement results were compared with each other, though the concentration values differed. 相似文献
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The concentration of mercury was determined in samples of the lichen Hypogymnia physodes, the moss Pleurozium schreberi, and the soil humus collected in Polish and Czech Euroregions Praded and Glacensis. The sampling sites were located in Bory Stobrawskie, Bory Niemodlińskie and Kotlina K?odzka in Poland, and in Jeseniki and Gory Orlickie in the Czech Republic. The mean concentrations of mercury accumulated in the lichen (0.129?mg?g(-1)), in the moss (0.094?mg?g(-1)) and in soil (0.286?mg?g(-1)) were fairly close to the corresponding concentrations in other low-industrialized regions. The highest concentrations of mercury were observed in the lichen and the moss samples from Kotlina K?odzka. The primary deposition of mercury was evaluated using the comparison factor, defined as the ratio of a difference between the concentrations of a bioavailable analyte in lichens and in mosses, to the arithmetic mean of these concentrations. 相似文献
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Trnkova L Fabrik I Huska D Skutkova H Beklova M Hubalek J Adam V Provaznik I Kizek R 《Journal of environmental monitoring : JEM》2011,13(10):2763-2769
Low-molecular mass proteins rich in cysteines called metallothioneins (MT) can be considered as markers for the pollution of the environment by metals. Here, we report on suggestion for an automated procedure for the isolation of MT followed by voltammetric analysis. Primarily, we optimized the automated detection of MT using an electrochemical analyser. It was found that the most sensitive and repeatable analyses are obtained at a temperature of 4 °C for the supporting electrolyte. Further, we optimized experimental conditions for the isolation of MT by using antibody-linked paramagnetic microparticles. Under the optimal conditions (4 h long interaction between the microparticles and MT), the microparticles were tested on isolation of various amounts of MT. The lowest isolated amount of MT by antibody-linked paramagnetic microparticles was 5 μg ml(-1) of MT (50 ng). The automated procedure of MT isolation was further tested on isolation of MT from guppy fish (Poecilia reticulata) treated with silver(i) ions (50 μM AgNO(3)). The whole process lasted less than five hours and was fully automated. We attempted to correlate these results with the standard method for MT isolation. The correlation coefficient is 0.9901, which confirms that results are in good agreement. Moreover, the concentration of silver ions in tissues of fish treated with Ag(i) ions was determined by high performance liquid chromatography with electrochemical detection. 相似文献
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Leonardo Gucciardo Anne Uyttebroek Ivo De Wever Marleen Renard Filip Claus Roland Devlieger Liesbeth Lewi Luc De Catte Jan Deprest 《黑龙江环境通报》2011,31(7):678-688
Sacrococcygeal teratoma (SCT) is one of the most common tumors in newborns with a birth prevalence of up to 1 in 21 700 births. Routine fetal anomaly screening programs allow for prenatal diagnosis in many cases. Fetal ultrasound with Doppler evaluation and more recently magnetic resonance imaging may be used to document the extent of the tumor as well as identifying the population at risk for serious fetal complications. Rapidly growing SCT and highly vascularized tumors are more likely to have hemodynamic repercussions. Fetal hydrops is usually considered as a poor prognostic marker and a potential indicator for fetal intervention. Newborns with SCT require stabilization prior to early surgical resection. In case of malignancy additional chemotherapy may be required. SCT may result in significant morbidity, either directly or as a consequence of surgical therapy. Careful postnatal follow-up is required for timely identification and treatment of complications as well as recurrence. This paper aims to review the perinatal management of this condition. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Matheus Ribeiro da Silva Assis Carmen Baur Vieira Julia Monassa Fioretti Mônica Simões Rocha Pedro Ivo Neves de Almeida Marize Pereira Miagostovich Tulio Machado Fumian 《Food and environmental virology》2016,8(4):305-309
Gemycircularvirus (GemyCV) is a group of viruses which has been recently proposed as a new viral genus detected in fecal and environmental samples around the world. GemyCVs have been detected in human blood, brain tissue, cerebrospinal fluid, and stool sample. In the present study, we demonstrate for the first time, through molecular detection and characterization, the presence of GemyCVs in environmental samples from Brazil. Our results show a percentage of positivity ranging from 69 (25/36) to 97 % (35/36) in river water samples collected in Manaus, Amazon region, and wastewater from a wastewater treatment plant located in Rio de Janeiro, respectively, revealing GemyCVs as an important environmental contaminant. 相似文献