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201.
The paper applies the community resilience approach to the post‐disaster case of Pescomaggiore, an Italian village affected by the L'Aquila earthquake in 2009. A group of residents refused to accept the housing recovery solutions proposed by the government, opting for autonomous recovery. They developed a housing project in the form of a self‐built ecovillage, characterised by earthquake‐proof buildings made of straw and wood. The project is a paradigmatic example of a community‐based response to an external shock. It illustrates the concept of ‘community resilience’, which is widely explored in the scientific debate but still vaguely defined. Based on qualitative methodologies, the paper seeks to understand how the community resilience process can be enacted in alternative social practices such as ecovillages. The goal is to see under which conditions natural disasters can be considered windows of opportunity for sustainability.  相似文献   
202.
A new approach to environmental studies was investigated by the authors, who propose the use of cryopreserved biological systems in ecotoxicological bioassays. The feasibility of spermiotoxicity tests using cryopreserved semen of the sea bream Sparus aurata, with sperm motility parameters as the endpoint, was evaluated. Thawed sperm was incubated in environmental samples (sediment elutriate and dumpsite leachate) and in a reference toxicant (cadmium) at scaled concentrations. Motility was then evaluated by video-microscopy using both visual and computer-assisted analyses. Activation time, sperm motility and velocity and motility duration were assessed on thawing and at the end of the incubation time, and the difference with respect to the control was statistically evaluated. All the endpoints of the bioassay proved to have good sensitivity even at the highest dilutions of the tested matrices. Observed differences in the sensitivity thresholds of the endpoints were considered to be representative of different aspects of sperm physiology. Therefore the proposed bioassay is a promising starting point for the development of toxicity tests that are increasingly tailored to the needs of ecotoxicology and environmental quality evaluation strategies for aquatic environments.  相似文献   
203.
The effects of two carbon-based nanomaterials, nano-sized carbon black (nCB), and single-layer graphene oxide (GO) on settlement of Amphibalanus amphitrite (Cirripedia, Crustacea) cypris larvae (cyprids) were assessed after 24, 48, and 72 h of exposure. Additionally, the effects of these nanomaterials on the mortality and swimming behaviour of the nauplius larvae (nauplii) of the same organism were determined after 24 and 48 h. The data indicate that nCB is more effective as a potential antisettlement agent than single-layer GO; moreover, nCB did not show any adverse effects on the larvae. The swimming behaviour of II stage nauplii of A. amphitrite exposed to a suspension of nCB was inhibited only at very high nCB concentrations (≥0.5 mg/mL). Single-layer GO, on the contrary, showed lower antisettlement effects and was more active in altering the survival and inhibiting the swimming behaviour of the nauplii. An indication of the toxic or non-toxic mechanisms of the antisettlement properties of both of these nanomaterials is provided by the reversibility of the antisettlement activity. In conclusion, we propose nCB as an innovative antifouling nanomaterial that shows low toxicity towards the model organism (crustaceans) used in this study.  相似文献   
204.
In this study, the effects of experimental variables such as type of solvent, sample/solvent ratio, and time of extraction have been evaluated to individuate the best results in phenolic recovery by Olive Pomaces (OP) belonging to Carolea and Ottobratica cultivars. Folin–Ciocaulteu procedure and DPPH and ABTS assays were used, respectively, for total phenol quantification and total antioxidant activity of pomace extracts. The ethanol/water mixture was resulted the most efficient extraction solvent for both olive cultivars. The highest amount of phenolic compounds (171 ± 4 mg of gallic acid 100 g?1 of dry pomace) was obtained after extraction at 120 min with 2:1 solvent/OP (v/w) of Ottobratica Olive Pomace. The recovery of phenol compounds from olive wastes increases the sustainability of sector, allowing obtaining an extract that could be a suitable alternative in the food industry to the use of synthetic antioxidants in order to improve the quality of foods.  相似文献   
205.
The distribution and potential bioaccumulation of dietary and waterborne cadmium and lead in tissues of sea bream (Sparus aurata), a major aquaculture species, was studied in relation to three different fish farming systems. Metallothionein levels in fish tissues were also evaluated. Results demonstrate that metal concentrations in various tissues significantly vary among fish culture systems. Different tissues show different capacity for accumulating heavy metals. The content of both cadmium and lead is not strictly correlated with that of metallothionein. Indeed, the marked accumulation of both metals in liver, as well as the high lead content found in gills and kidney, are not accompanied by a concomitant accumulation of metallothioneins in these tissues. No correlation is present between heavy metals and metallothionein content in muscle tissue. The results also demonstrate that cadmium accumulates mainly via dietary food, whereas lead accumulation is not of food origin. Noteworthy is that the concentration of the two metals found in muscle in all instances is lower than the limits established by European Union legislation for fish destined for human consumption.  相似文献   
206.
Using short-term hemocyte cultures of the colonial ascidian Botryllus schlosseri exposed to various sublethal concentrations of Diuron (3-(3,4-diclorophenyl)-1,1-dimethylurea) and TCMS pyridine (2,3,5,6-tetrachloro-4-(metylsulphonyl)pyridine), we evaluated their immunotoxic effects through a series of cytochemical assays previously used for organotin compounds. At concentrations higher than 250 micro M and 10 micro M for Diuron and TCMS pyridine, respectively, both biocides exerted immunosuppressant effects on Botryllus hemocytes, causing i) deep changes in the cytoskeleton that irreversibly affect cell morphology and phagocytosis, ii) induction of DNA damage, iii) leakage of oxidative and hydrolytic enzymes due to membrane alteration. Unlike organotin compounds, Diuron and TCMS pyridine do not inhibit cytochrome-c-oxidase, and only TCMS pyridine triggers oxidative stress. When co-present, they exert an antagonistic interaction on cytoskeletal components.  相似文献   
207.
The leather tanning industry is perceived as responsible of a significant consume of natural resources and output of wastes such as high concentration of organics, salts and heavy metals such as chromium, both in solid and liquid form as a result. Now as ever the future of tanneries strongly depends on the increase of their awareness that a sustainable industry for the future means embracing a forward-looking philosophy of the leather making process through optimal resource management within the tannery. This study reports the characterization of some chemicals used in a large tanning district area in terms of COD, BOD, aromaticity (UV280) and double bond (UV254) absorbance measurements, toxicity on fresh and saline water as well as terrestrial species, GC-MS scanning. The study provides a consistent set of information on tannin-associated concentration-related trends and suggests novel criteria in defining control quality for evaluating environmental impact of leather tanning industry.  相似文献   
208.
资料同化方法在空气污染数值预报中的应用研究   总被引:4,自引:1,他引:4  
基于第5代中尺度非静力气象模式MM5以及区域气溶胶和沉积模式REMSAD耦合的空气污染数值预报模型系统,分别采用最优插值法和集合卡尔曼滤波法对南京2002-08~2002-09 NOx和SO2模型预报结果进行了资料同化试验,结果表明,NOx和SO2经最优插值法同化后偏差平均值的改进率分别为34.20%、47.53%,均方根误差的改进率分别为31.95%、42.04%;NOx和SO2经集合个数为30的集合卡尔曼滤波法同化后偏差平均值的改进率分别为26.73%、60.75%,均方根误差的改进率分别为25.20%、55.16%;说明最优插值法和集合卡尔曼滤波法都具有改善空气污染数值预报中污染物浓度初始场的作用.进行了集合卡尔曼滤波法中集合个数为61时2种同化方法同化效果比较的试验,结果表明,随着集合卡尔曼滤波法集合个数的增加,NOx和SO2的同化效果都较集合个数为30时有所改善,并且,集合卡尔曼滤波法对NOx和SO2模式预报结果的改善效果将好于最优插值法.  相似文献   
209.
A coupled atmosphere–ocean general circulation model, ECHAM5-MPIOM, was used to study the multicompartmental cycling and long-range transport of persistent and semivolatile organics. Multiphase systems in air and ocean are covered by submodels for atmospheric aerosols, HAM, and marine biogeochemistry, HAMOCC5, respectively. The model, furthermore, encompasses 2D surface compartments, i.e. top soil, vegetation surfaces and sea-ice. The total environmental fate of γ-hexachlorocyclohexane (γ-HCH, lindane) and dichlorophenyltrichloroethane (DDT) in agriculture were studied.DDT is mostly present in the soils, the water-soluble γ-HCH in soils and ocean. DDT has the longest residence time in almost all compartments. Quasi-steady state with regard to substance accumulation is reached within a few years in air and vegetation surfaces. In seawater the partitioning to suspended and sinking particles contributes to the vertical transport of substances. On the global scale deep water formation is, however, found to be more efficient. Up to 30% of DDT but only less than 0.2% of γ-HCH in seawater are stored in particulate matter.On the time scale studied (1 decade) and on global scale substance transport in the environment is determined by the fast atmospheric circulation. The meridional transport mechanism, for both compounds, is significantly enhanced by multi-hopping. Net meridional transport in the ocean is effective only regionally, mostly by currents along the western boundaries of Africa and the Americas. The total environmental burdens of the substances experience a net northward migration from their source regions, which is more pronounced for DDT than for γ-HCH. Due to the application distribution, however, after 10 years of simulation 21% of the global environmental burden of γ-HCH and 12% of DDT have accumulated in the Arctic.  相似文献   
210.
The categories of urban workers undergoing prolonged exposure to gasoline due to vehicle emissions, evaporation and traffic fumes are considered occupationally exposed to benzene, even if at low concentrations. The aim of this study was to evaluate the specificity of unmetabolized benzene excreted in urine (UBz) and S-phenylmercapturic acid (SPMA) as biomarkers of exposure to very low levels of benzene, and to study the impact of putative individual confounders like smoking and alcohol habits, co-exposure to other toxicants and body mass index on the exposure assessment. Environmental and biological monitoring of exposure to benzene were performed in 114 Urban Policemen. The mean value of UBz in non-smokers was significantly lower than in either groups of light to moderate smokers and heavy smokers (0.24, 1.82 and 2.82 microg L(-1), respectively). On the contrary, SPMA values did not discriminate exposure resulting from smoking habits. Moreover, the concentration of UBz in non-smokers appears to be correlated with environmental benzene concentration (BenzA) (R(2)=0.13, beta=0.37, p=0.002). On the other hand, no significant correlation was found between SPMA concentration (corrected for creatinine excretion and log transformed, LogSPMA) and LogBenzA (R(2)=0.003, beta=0.05, p=0.6). Our findings reinforce previous research on the use of unmetabolized urinary benzene as a specific and sensitive biomarker of low-level exposure to benzene and confirm that smoking habits strongly influence the excretion of UBz.  相似文献   
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