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Jyri Seppla Matti Melanen Ilmo Menp Sirkka Koskela Jyrki Tenhunen Marja‐Riitta Hiltunen 《Journal of Industrial Ecology》2005,9(4):117-130
The concept of eco-efficiency is commonly referred to as a business link to sustainable development. In this article, ecoefficiency is examined at a regional level as an approach to promoting the competitiveness of economic activities in the Finnish Kymenlaakso region and mitigating their harmful impacts on the environment. The aim is to develop appropriate indicators for monitoring changes in the eco-efficiency of the region. A starting point is to produce indicators for the environmental and economic dimensions of regional development and use them for measuring regional eco-efficiency. The environmental impact indicators are based on a life-cycle assessment method, producing different types of environmental impact indicators: pressure indicators (e.g., emissions of CO2 ), impact category indicators (e.g., CO2 equivalents in the case of climate change), and a total impact indicator (aggregating different impact category indicator results into a single value). Environmental impact indicators based on direct material input, total material input, and total material requirement of the Kymenlaakso region are also assessed. The economic indicators used are the gross domestic product, the value added, and the output of the main economic sectors of Kymenlaakso. In the eco-efficiency assessment, the economic and environmental impact indicators are monitored in the same graph. In a few cases eco-efficiency ratios can also be calculated (the economic indicators are divided by the environmental indicators). Output (= value added + intermediate consumption) is used as an economic indicator related to the environmental impact indicators, which also cover the upstream processes of the region's activities. In the article, we also discuss the strengths and weaknesses of using the different environmental impact indicators. 相似文献
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The plasma membrane of Streptococcus cremoris: isolation and partial characterization 总被引:1,自引:0,他引:1
Marja A. Rimpiläinen Kaarina Niskasaari† Katri M. S. Juutinen† Eeva-Liisa Nurmiaho-Lassila‡ Raili I. Forsean† 《Journal of applied microbiology》1986,60(5):389-394
Plasma membrane was isolated from Streptococcus cremoris using mutanolysin from a streptomycete as the cell wall-degrading enzyme and phenylmethylsulfonyl fluoride as protease inhibitor. The specific activity of membrane-bound enzyme, adenosine triphosphatase (ATPase), was 4 μmol/mg protein per min, which was 5–10 times higher than the activity found in other fractions obtained during the isolation procedure. The number of polypeptides in the plasma membrane was approximately 50 with molecular weights 13 500–100 000, minor changes in the polypeptide pattern were observed when the plasma membrane was isolated without a protease inhibitor. The chemical composition of the membrane preparation was 49.7% protein, 21.9% lipid, 5.1% aminosugars, 17.3% RNA and 0.03% DNA. Electron microscopic examination confirmed the membrane to be practically devoid of cell wall components. Our results indicate that the membrane integrity is well retained and therefore the membrane preparation is suitable for detailed studies on vectorial metabolism and its enzymes, e.g. ATPase. 相似文献
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In experiments on asynchronous population of HeLa S3 cells a study was made of the possibility of assessing DNA lesions which remained unrepaired for a long period of time following gamma-irradiation: in generation "O" directly affected by radiation and in generation "I" following the irradiated one. The presence of DNA damages was estimated by the reduction in survival of exposed cells incubated with inhibitors of repair and replicative syntheses of DNA, namely, with arabinoside cytosine and hydroxyurea. A considerable enhancement of the radiation effect was noted with the inhibitors added 0-6 h after irradiation (generation "O"), and a marked increase in the cell death was registered with the preparations injected 24-30 h after exposure (generation "I"). It is assumed that minor residual lesions persist in the generation of cells, following the one directly affected by gamma-radiation, which have completed the first postirradiation mitosis. 相似文献
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On the basis of our own data and those reported in the literature we have made an attempt to follow the fate of the DNA lesions which remain unrepaired during a long period of time, and their possible role in the fate of irradiated cells. The presence of long-lived ("residual") damages is determined by the changes in survival of exposed cells treated, at different times after irradiation, with a mixture of arabinoside cytosine and hydroxyurea. It is shown that "residual" damages can probably exist in the exposed generation and be retained in that following the irradiated one, i.e. after the first mitosis. The nearest descendants of exposed cells (the 3d-5th generations) exhibit a 50% decrease in the rate of DNA synthesis and fall of their proliferative activity, as well as a decrease in the rate of reproduction of their remote descendants. The comparison of the results obtained with those reported by other authors enable us to assume that "residual" DNA lesions play an important role in the fate of exposed cells, that is, in reproductive death, radiation mutagenesis, and malignant transformations. 相似文献
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UDPglucosyltransferase and its kinetic fluorimetric assay 总被引:1,自引:0,他引:1
A rapid, kinetic assay for UDPglucosyltransferase has been developed using 1-naphthol as substrate. It is based on the continuous fluorimetric monitoring of 1-naphthyl glucoside formation during the reaction at physiological pH. The conjugate is easily distinguished from aglycone, since their fluorimetric properties differ. Glucoside biosynthesis in vitro by microsomal preparations isolated from the gut and fat body of cockroaches Periplaneta americana and Leucophaea maderae, and from the green gland and hepatopancreas of the crayfish Astacus astacus, has been demonstrated. The effects of buffer, pH, MgCl2, UDP-glucuronic acid, UDP-N-acetylglucosamine, sodium cholate and sonication on the enzyme activity have been assessed. The kinetic parameters of 1-naphthol and UDP-glucose have also been determined. 相似文献
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R. Hasselback Marja Soots John Curtis G. L. Robertson D. H. Cowan G. D. Hart 《CMAJ》1967,96(25):1610-1614
The presence of definite cytoplasmic granulation in at least some of the malignant cells was used as the sole criterion to separate 156 patients with acute leukemia into two groups: 110 with myeloblastic (AML), and 46 with lymphoblastic or stem cell leukemia (ALL). The median survival from the onset of symptoms in patients with AML was 20 weeks, and those with ALL 37 weeks. The difference in survival in these two groups is much greater for patients under the age of 25 than for those over the age of 25. 相似文献
10.
L C Sellin K Mattila A Annila J J Schmidt J J McArdle M Hyv?nen T T Rantala T Kivist? 《Biophysical journal》1996,70(1):3-13
The 22-residue toxic peptide (WTX1) from the venom of the Southeast Asian snake Trimeresurus wagleri has multiple sites of action, but its lethal effect has been attributed to blocking the postsynaptic acetylcholine receptor at the neuromuscular junction. The 3-dimensional structure of WTX1 was studied using 2-dimensional nuclear magnetic resonance spectroscopy, circular dichroism, and computer simulations. In aqueous solution, WTX1 was shown to have extended and flexible "tails" defined by a short, rigid disulfide-bonded loop. The flexible regions can undergo structural rearrangement when moved from an aqueous to a less polar environment and may contribute to its effectiveness at different receptor sites. By substituting Gly or Phe for His at position 10, significant effects on the disulfide bond formation and, thereby, the activity of the peptide were observed. These results suggest that even subtle differences in single residues can have profound effects on the dynamics of folding, disulfide bond formation, and activity of this toxic peptide. 相似文献