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The concentrations of Hg in three groups of algae (Phaeophyta, Chlorophyta, and Rhodophyta) found in the Canary Islands littoral were determined. The mean concentrations found were, respectively: Phaeophyta: 0.13 mg kg−1 (range 0.01 to 2.30 mg kg−1); Chlorophyta: 0.13 (range 0.025 to 0.36 mg kg−1); Rhodophyta: 0.11 mg kg−1 (range 0.02 to 0.28 mg kg−1). There are no relevant differences in the contents of Hg at group level and at species level, only a sample of Phaeophyta presents an abnormally high concentration (>1 mg kg−1), corresponding to a sampling station nearby an urban drain.  相似文献   
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During the last decade, Sustainability Reporting (SR) has been increasingly adopted by corporations worldwide. This is evidenced by the adoption of several guidelines, such as the ISO 14000 series, the Social Accountability 8000 standard, and the GRI Sustainability Guidelines. SR shows promise to help corporate leaders and their employees to contribute towards achieving sustainable societies. However, most of the guidelines and standards address sustainability issues through comparmentalisation, thereby, leading to the separation of the economic, environmental, and social dimensions. Due to these divisive approaches, holistic assessments of the effects of their efforts are seldom properly integrated into coporate decisions and procedures to make improvements for example through Cleaner Production, Worker Health and Safety, Consumer Safety, and reductions in the negative short and long-term Social and Environmental Impacts.This paper analyses SR reports from three companies with the help of Grounded Theory's constant comparative analysis. This analytical framework helped the authors to systematically assess the degree to which the companies addressed economic, ecological and social issues separately or in an integrated and inter-linked manner. From the inter-linkages found, a new category is proposed to be added to future SR. This new category can help corporate SR planners and researchers on sustainability reports to better understand how the company leaders understand their responsibilities with regard to SD. These inter-connectednesses are highly relevant in many short and long-term dimensions of supply chain management, global warming, ecological disruption and societal equity issues, especially with regard to the local, national and global energy issues of fuels and oils, the central themes of the conference at which this paper was originally presented. It also plays a key role in real, long-term changes towards Sustainability, where the time dimension plays a key role in human survival on Planet Earth.  相似文献   
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Spodoptera frugiperda Smith (Lepidoptera: Noctuidae) is a serious pest of corn in several American countries. It is mainly controlled with synthetic insecticides. The objectives of this study were to evaluate the effects of the natural products, neem oil and pyroligneous extract, and the synthetic insecticide, lufenuron, at 2.50mL water (0.25 %) on the mortality of 2-, 4- and 6-day-old caterpillars of S. frugiperda, and their selectivities against fourth instar larvae of Eriopis connnexa Germar (Coleoptera: Coccinellidae). Four- and 6-day-old S. frugiperda caterpillars showed higher mortality after exposure to neem oil (83.33 ± 0.83 and 89.58 ± 0.90 %, respectively) and lufenuron (95.83 ± 0.96 and 85.41 ± 0.83 %), compared to pyroligneous extract (68.75 ± 0.69 and 31.25 ± 0.31 %). The deleterious effect of pyroligneous extract was higher in 2- (83.33 ± 0.83 % mortality) and 4-day-old (68.75 ± 0.69 %) S. frugiperda caterpillars than in 6-day-old caterpillars (31.25 ± 0.31 %). Larval mortality of the predator E. connexa was lower with neem oil and pyroligneous extract (25.00 ± 0.33 %) than with lufenuron (91.66 ± 1.22 %). Neem oil is thus recommended for control of S. frugiperda because of its high toxicity, combined with its relatively low toxicity to larvae of the natural enemy E. connexa.  相似文献   
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