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431.
Glycaemia, a classical indicator of stress, xanthine oxidase and aldehyde oxidase which are involved in phase I detoxication were investigated in two different fish species from two rivers with different pollution levels in the Western Niger-Delta. Four sampling zones covering the entire lengths of Warri and Ethiope Rivers respectively were used in this study. For each species of fish five were obtained from a sampling zone in a river. Blood glucose was significantly higher (P < 0.001) in M. electricus from Warri River (82.13 +/- 5.50 mg cm(-3)) compared to the same species from Ethiope River (36.47 +/- 1.49 mg cm(-3)). With the same parameter a similar profile was observed for C. gariepinus; Warri River (56.92 +/- 10.31 mg cm(-3)); Ethiope River (37.65 +/- 0.90 mg cm(-3)) which was also significant (P < 0.01). The activity of xanthine oxidase in M. electricus from Warri River (255.80 +/- 41 it mol cm(-3)) was significantly higher (P < 0.001) compared to the value obtained for the same species (108 +/- 22.36 micro mol cm(-3)) from Ethiope River. Also the activity of xanthine oxidase in C. gariepinus from Warri River (197 +/- 34.65 micro mol cm(-3)) was significantly higher (P < 0.001) when matched with the value obtained for the same species (78.40 +/- 26.84 micro mol cm(-3)) from Ethiope River. That blood glucose level was related to xanthine oxidase activity in the two fish species from Warri River was supported by the high positive correlation between these two parameters (M. electricus. r = 1: C. gariepinus, r = 0.71). The activity of aldehyde oxidase in C. gariepinus from Warri River (143.80 +/- 28.45 micro mol cm(-3)) was significantly higher (P < 0.001) compared to the value obtained for the same species (61.20 +/- 15.21 micro mol cm(-3)) from Ethiope River. A similar profile in aldehyde oxidase activity observed for M. electricus; Warri River (130 +/- 28.39 micro mol cm(-3)); Ethiope River (89 +/- 19.70 micro mol cm(-3)) but an inferior statistical variation (P < 0.05) was obtained. The results obtained in this study indicate that the level of xanthine oxidase in M. electricus is a more specific marker and to a lesser extent its activity in C. gariepinus in monitoring environmental stress due to pollution.  相似文献   
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For governments and for manufacturing companies, global warming, rising energy prices, and customers’ increasing ecological awareness have pushed energy efficient manufacturing to the top of the agenda. Governments and companies are both striving to identify the most effective measures to increase energy efficiency in manufacturing processes. Based on results of a recent EU-funded roadmapping project, this paper highlights the needs of industrial companies for integrating energy efficiency performance in production management. First, it analyses concepts and tools for measurement, control and improvement of energy efficiency in production management proposed in literature. Second, the paper outlines that ICT tools and standardization are important enablers for energy efficient manufacturing. Third, industrial needs in these areas are presented based on expert interviews. The industrial needs thus identified are contrasted with concepts proposed in literature to point out the implementation gaps between practice and theory. The paper demonstrates that there exists a gap between the solutions available and the actual implementation in industrial companies. It concludes by deriving requirements for energy management in production that future collaborative research projects should address.  相似文献   
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The population structure and biological parameters of the European whitefish, Coregonus lavaretus (L.), have been analyzed in a technogenically polluted water body. The biochemical state of the whitefish and the fauna and morphology of helminths parasitizing them have been assessed. It is shown that the species composition of the fish, plankton, benthos, and parasite faunas of this water body are depleted and the morphological parameters of common fish parasites are altered. It is noted that, in addition to adaptive rearrangements in biochemical metabolism, the whitefish from the transformed water body are characterized by a reduction in the level of protein synthesis in muscles and the rate of aerobic energy metabolism in the liver and muscles.  相似文献   
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Für die Anwendung der sequentiellen Schwermetallextraktion auf Proben, die nur im Milligramm-Bereich erhalten werden k?nnen (Mikroproben, wie z. B. Staubniederschl?ge), wurde die Methode vonZeien &Brümmer (1989) weiterentwickelt. Der Extraktionsma?stab wurde um den Faktor 1∶100 verringert und die Reproduzierbarkeit des Verfahrens mit variablen Probenmengen um 20mg und einem Extraktionsvolumen von 500 μl mit Hilfe von Standardb?den nachgewiesen. M?gliche Einflüsse variabler Extraktionsverh?ltnisse (Verh?ltnis von Probenmenge zu Extraktionsvolumen) sowie eine aufwendige Vorbehandlung von Staubproben, die nach der Bergerhoff-Methode (VDI 2119/2, 1972) gesammelt wurden, lagen bei diesen Untersuchungen weitgehend im Variationsbereich des Verfahrens. Die sequentielle Extraktion kann folglich zur Untersuchung der Mobilisierbarkeit von Schwermetallen auch aus Mikroproben mit variablen Probenmengen eingesetzt werden. Mit Hilfe dieses Verfahrens wurden die Mobilisierbarkeiten von Zink, Kupfer und Blei der Schluff- und Tonfraktion von Stra?ensedimenten mit Staubniederschl?gen an zwei urbanen Standorten mit unterschiedlicher, verkehrsbedingter Schwermetallbelastung verglichen. Diese Untersuchungen werden in Teil 2 (“Sequentielle Schwermetallextraktion von st?dtischen St?uben”) vorgestellt.  相似文献   
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The Model of Humus Balance was used to estimate the influence of climate effects and changing agricultural practices on carbon (C) levels in soddy–podzolic soils in the Russian Federation for the years 2000–2050. The model was linked with a spatial database containing soil, climate and farming management layers for identification of spatial change of C sequestration potential. Analysis of relationships between C, soil texture and climate indicated that compared with a business-as-usual scenario, adaptation measures could increase the number of polygons storing soil organic carbon (SOC) by 2010–2020. The rate of possible C loss is sensitive to the different climate scenarios, with a maximum potential for SOC accumulation expected in 2030–2040, thereafter decreasing to 2050. The effect is most pronounced for the arid part of the study area under the emission scenario with the highest rate of increase in atmospheric CO2 concentration, supporting findings from the dynamic SOC model, RothC. C sequestration during the study period was permanent for clay and clay loam soils with a C content of more than 2%, suggesting that C sequestration should be focused on highly fertile, fine-textured soils. We also show that spatial heterogeneity of soil texture can be a source of uncertainty for estimates of SOC dynamics at the regional scale. Figures in color are available at  相似文献   
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