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The levels and specific profiles of polychlorinated dibenzo-p-dioxins, dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) in Mytilus galloprovincialis from the Mar Grande and the Mar Piccolo of Taranto were determined during the extensive monitoring plan of Local Health Authority to assess PCDD/Fs and DL-PCBs contamination in food and farm products, within 20 km from the industrial areas of Taranto, between March and December 2011. The average Total Toxicity Equivalence (TEQ) values for the sum of PCDD/F and DL-PCBs ranged from 1.61 to 5.63 pg WHO2005-TEQ g?1 wet weight basis, with the highest in the first inlet of the Mar Piccolo. In particular, DL-PCBs were the dominant chemicals in all samples, followed by PCDFs and PCDDs. Congener patterns in mussels were similar, indicating a homogeneous behavior in studied areas and, probably, the same type of source. The seasonal concentrations trend showed a relevant increase of dioxin and dioxin-like PCBs TEQs during the summer months, exceeding the limits set by the European Community for food and foodstuff. Reducing PCDD/Fs and PCBs is necessary to decrease contamination levels in order to safeguard marine ecosystem and human health in the Taranto area.  相似文献   
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Previous research has established that perceptions of organizational politics are associated with negative organizational outcomes. However, this may not hold true for all individuals. We offer subordinate and supervisor political skill, the ability to understand interactions at work and to use that understanding to effectively influence others, as possible moderators. Specifically, this study investigates the impact of both employees' self‐rated political skill and their managers' political skill on job satisfaction, job performance, and manager‐rated commitment. We examined these relationships in an organizational sample of 106 matched dyadic pairs and found mixed support for the joint moderating effect of self and manager political skill on the politics perceptions‐outcome relationships. Strengths, limitations, and directions for future research are discussed. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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Trace elements and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were analyzed in soils from rural and light-industrialized sites (n=168) of Province of Pavia (Northern Italy). Most of the trace element values fit in typical ranges of concentrations in soils and are similar to the ones reported for rural sites in Italy or sites with no direct anthropogenic impact. Total concentrations of 2,3,7,8 chlorine substituted PCDD/Fs in superficial soils ranged between 24.4 and 1287 pg g(-1) dw (0.5-28.9 pg WHO(98)-TEQ g(-1) dw). The North Eastern part of the Province presented significantly higher levels (p<0.001) than the rest of the Province for As, Cd, Hg, Pb, Zn and PCDD/Fs. While the existence of a defined heavy metal polluting source for this specific site has been suggested, in the case of PCDD/Fs, profiles were not linked to any specific emission source fingerprint. In the whole extension of Pavia Province, OCDD/F dominated the 2,3,7,8 chlorine substituted congener soil pattern, followed by the 1,2,3,4,6,7,8 hepta-CDD/F congener. Principal Component Analysis (PCA) showed that this profile could not be associated to any described PCDD/F emission source fingerprint and was relatively similar to the baseline deposition of sites with no direct impact of PCDD/F emission sources independently of land use.  相似文献   
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The investigations carried out during 2005 by state-run Italian laboratories within the framework of controls seeking pesticide residues monitoring in foodstuffs involve quantifying the levels of such residues in fruit and vegetable produce and their processed products: oil, wine and fruit juices. The Italian Ready-Meal Residue Project, promoted by the pesticides working group of Italian Environmental Agencies, seeks to asses the quantity of pesticides in pre-prepared (ready-to-eat) lunches (comprising a first course, side dish, fruit, bread and wine), and to quantify the amounts consumed and compare with the acceptable daily intake ADIs.The data provided by 16 laboratories which analyzed 50 complete meals in 2005 (samples taken on 8 February, 26 May, 24 October, 21 December 2005) showed residues in 39 lunches, with an average number of 2.4 pesticides in each meal and a maximum of 10 pesticides. The most frequently found substances were: pirimiphos-methyl (20 times), procymidone (17), pyrimethanil (7), iprodione (7), cyprodinil (7), fenitrothion (6), diphenylamine (6), chlorpyrifos (6), metalaxyl (5) and chlorpyrifos-methyl (5).The distribution of residues among each dish of the meal was also examined, and the results showed that: 77.3% of the residues were present in the fruit, 14.9% in the wine, 3.0% in the main course, 2.8% in the bread and 2.1% in the side dish. Assuming that two meals are consumed per day, the daily intake of pesticide residues was calculated on a daily basis, in relation to normal body weight (60 kg for an adult, 40 kg for a teenager, 20 kg for a child) and compared with the ADI values established by the European Union. In the case of adults, the average daily intake of pesticides in relation to ADI was 2.6% with a maximum of 73.3%; for teenagers it was 4.9% with a maximum of 109% and for children it was 9.8% with a peak of 219%.  相似文献   
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The non-ionic surfactant Brij 35 was effectively removed from concentrated aqueous solution by the peroxymonosulfate/Co(II) system, using oxone (2KHSO5·KHSO4·K2SO4) as a source of peroxymonosulfate. At pH = 2.3 and initial Brij 35 concentration in the range 680-2410 mg L−1, 86-94% removal was achieved after 24 h, using Co(II) = 15 μM and oxone = 5.9 mM. The effectiveness of removal did not change when initial pH was in the range 2.3-8.2. After five subsequent additions of Co(II) and oxone to the solution, COD and TOC removals increased up to 64% and 33%, respectively. Radical quenching tests confirmed that sulfate radical was the dominant radical species in the system. The main identified by-products from surfactant degradation were: (a) low molecular weight organic acids; (b) aldehydes and formates with shorter ethoxy chain than Brij 35; (c) alcohol ethoxylates carrying hydroxyl groups bonded to ethoxy chain. By-products identification allowed to hypothesize the pathways of Brij 35 degradation.  相似文献   
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In this paper, a literature review about optical remote sensing (RS) of O3 stress is presented. Studies on O3-induced effects on vegetation reflectance have been conducted since late ‘70s based on the analysis of optical RS data. Literature review reveals that traditional RS techniques were able to detect changes in leaf and canopy reflectance related to O3-induced stress when visible symptoms already occurred. Only recently, advanced RS techniques using hyperspectral sensors, demonstrated the feasibility of detecting the stress in its early phase by monitoring excess energy dissipation pathways such as chlorophyll fluorescence and non-photochemical quenching (NPQ). Steady-state fluorescence (Fs), measured by exploiting the Fraunhofer line depth principle and NPQ related xanthophyll-cycle, estimated through the photochemical reflectance index (PRI) responded to O3 fumigation before visible symptoms occurred. This opens up new possibilities for the early detection of vegetation O3 stress by means of hyperspectral RS.  相似文献   
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