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991.
The changing Arctic environment is affecting zooplankton that support its abundant wildlife. We examined how these changes are influencing a key zooplankton species, Calanus finmarchicus, principally found in the North Atlantic but expatriated to the Arctic. Close to the ice-edge in the Fram Strait, we identified areas that, since the 1980s, are increasingly favourable to C. finmarchicus. Field-sampling revealed part of the population there to be capable of amassing enough reserves to overwinter. Early developmental stages were also present in early summer, suggesting successful local recruitment. This extension to suitable C. finmarchicus habitat is most likely facilitated by the long-term retreat of the ice-edge, allowing phytoplankton to bloom earlier and for longer and through higher temperatures increasing copepod developmental rates. The increased capacity for this species to complete its life-cycle and prosper in the Fram Strait can change community structure, with large consequences to regional food-webs.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01667-y.  相似文献   
992.
Environmental Science and Pollution Research - Sediment toxicity plays a fundamental role in the health of inland fish communities; however, the assessment of the hazard potential of contaminated...  相似文献   
993.
A salt-wedge stratified microcosm, spiked with 31 target analytes, including PCBs, organochlorine and organophosphorous pesticides, triazines, organophosphate flame retardants and caffeine (an urban wastewater molecular marker), was setup. Compound behaviour was monitored during a four week period, by sampling at six different levels of the water column, in order to understand the transport and loss processes of the different classes of chemical substances. Compound transport from one water body to the other has been positively correlated with diffusion via their molar volume. Target analytes loss has been positively correlated with evaporation via their K(H) and with degradation via their halve-lives. From these two processes, evaporation was found to be predominant using a multiparametric regression.  相似文献   
994.
The aim of this work was to determine the level of benzene, toluene, o-xylene and m, p-xylene (BTX) in air samples collected from the cabins of new and used vehicles of the same model. Ten new vehicles were examined in order to check interior emission from materials used to equip the passenger compartment. In order to compare and define the impact of exhaust gases, air samples were also collected from two used cars, at different mileages (up to 20,000 kin). All vehicles tested were of the same type. Samples were collected onto Carbograph 1TD sorbent, thermally desorbed and examined with the use of gas chromatography with flame ionisation and mass spectrometry detectors. All results obtained were referred to Polish and German requirements for indoor air quality (both in public buildings and in workspace environments). Average benzene, toluene, o-xylene and m, p-xylene concentrations in new cars were determined at the level of 11.8 μg/m^3, 82.7 μg/m^3, 21.2 μg/m^3 and 89.5 μg/m^3, respectively. In the used cars, BTX concentration increased with increasing vehicle mileage. The most significant increase of BTX concentration was observed above 11,000 km mileage.  相似文献   
995.
Environmental Science and Pollution Research - The use of biochar in soil remediation is a promising method to deal with metal contamination. In the present study, the influence of biochar...  相似文献   
996.
Even though the global COVID-19 pandemic may affect how medical care is delivered in general, most countries try to maintain steady access for women to routine pregnancy care, including fetal anomaly screening. This means that, also during this pandemic, fetal anomalies will be detected, and that discussions regarding invasive genetic testing and possibly fetal therapy will need to take place. For patients, concerns about Severe Acute Respiratory Syndrome-Corona Virus 2 will add to the anxiety caused by the diagnosis of a serious fetal anomaly. Yet, also for fetal medicine teams the situation gets more complex as they must weigh up the risks and benefits to the fetus as well as the mother, while managing a changing evidence base and logistic challenges in their healthcare system.  相似文献   
997.
Waste disposal is an issue that is becoming increasingly important in policy terms in the European Union, and in Italy, a country showing strong geographical heterogeneity in waste management. This paper analyses the process of decoupling/delinking between economic growth and landfilling trends in a framework where economic, policy, geographical elements and spatial issues are all considered as drivers behind the phenomenon. We exploit an original and very rich provincial panel dataset over 1999–2005 for the 103 Italian provinces. Evidence shows that the observed ‘absolute’ decoupling between economic growth and landfilling is driven by a mix of structural factors. Among the main factors, population density, more than the provincial income level, emerges as a crucial driver: local opportunity costs and landfill externalities matter in shaping waste policies and local commitment to a transition away from landfilling of waste (landfill diversion). However, not only structural factors are relevant. If on the one hand landfill taxes are not a significant driver of the phenomenon, waste management tools, such as separated collection for recycling, and the tariff system connected to waste services, bring about significant effect on the amount of landfilled waste. Moreover, regarding the analysis of spatial interrelations across provinces, we note that the presence of incinerators in nearby provinces increases landfill diversion, due probably to free riding behaviour or intra-provinces ‘agreements’ on waste management; this is not true for nearby landfill sites, that cause for a given province a strong lock in effect. Future research could strengthen the analysis of policy effectiveness at regional level, focusing on policy endogeneity, and the full investigation of spatial correlations in waste disposal performances.  相似文献   
998.
This paper presents the results of an intensive monitoring activity of the particulate, fall-out and soil of selected living areas in Italy with the aim to detect the asbestos concentration in air and subsequent risk of exposure for the population in ambient living environments, and to assess the nature of the other mineral phases composing the particulate matrix. Some areas were sorted out because of the presence of asbestos containing materials on site whereas others were used as blank spots in the attempt to detect the background environmental concentration of asbestos in air. Because the concentration of asbestos in ambient environments is presumably very low, and it is well known that conventional low–medium flow sampling systems with filters of small diameter (25 mm) may collect only a very small fraction of particulate over a short period, for the first time here, an intense monitoring activity was conducted with a high flow sampling system. The high flow system requires the use of large cellulose filters with the advantage that, increasing the amount of collected dust, the probability to collect asbestos fibers increases. Both the protocol of monitoring and analysis are novel and prompted by the need to increase the sensitivity towards the small number of expected fibers. With this goal, the collection of fall-out samples (the particulate falling into a collector filled with distilled water during the monitoring shift) and soil samples was also accomplished. The analytical protocol of the matrix particulate included preliminary X-ray powder diffraction (XRPD), optical microscopy and quantitative electron microscopy (SEM and TEM). Correlations with climatic trends and PM10 concentration data were also attempted.The surprising outcome of this work is that, despite the nature of the investigated site, the amount of dispersed asbestos fibers is very low and invariably lower than the theoretical method detection limits of the SEM and TEM techniques for identification and counting of asbestos fibers. The results are compared to the literature data worldwide and an updated model for asbestos fibers dispersion in ambient environments is proposed.  相似文献   
999.
1000.
This study is aimed to investigation of the effect of modulated 450 MHz microwave radiation on the EEG inter-hemispheric asymmetry. Ten cycles of the microwave exposure (1 min off and 1 min on) at fixed modulation frequency were applied on two groups of healthy volunteers. The first group of 13 subjects was exposed to microwave radiation modulated at 14 Hz and the second group of 15 subjects at 40 Hz frequency. The peak specific absorption rate (SAR) average over 1 g was 0.303 W/kg. Differences in SAR between hemispheres were up to 20 dB. Rod antenna was located from the left side of the head. Differences of relative changes in EEG energy between symmetric channels FP1–FP2, T3–T4, P3–P4 and O1–O2 in exposed and sham conditions were analysed. The results showed increase in EEG energy from the left side caused by microwave exposure. Statistical analysis done for the whole group of subjects didn’t reveal significant differences in inter-hemispheres asymmetry between exposed and sham conditions. However, statistical analysis performed for individual subjects detected significant differences in asymmetry caused by exposure for 15–35% of individuals.  相似文献   
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