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61.
Andreas Kicherer Stefan Schaltegger Heinrich Tschochohei Beatriz Ferreira Pozo 《The International Journal of Life Cycle Assessment》2007,12(7):537-543
Goal, Scope and Background The eco-efficiency analysis and portfolio is a powerful decision support tool for various strategic and marketing issues.
Since its original academic development, the approach has been refined during the last decade and applied to a multitude of
projects. BASF, as possibly the most prominent company using and developing this tool, has applied the eco-efficiency approach
to more than 300 projects in the last 7 years. One of the greatest difficulties is to cover both dimensions of eco-efficiency
(costs or value added and environmental impact) in a comparable manner. This is particularly a challenge for the eco-efficiency
analyses of products.
Methods In this publication, an important approach and field of application dealing with product decisions based on the combination
of Life Cycle Cost (LCC) and Life Cycle Assessment (LCA) is described in detail. Special emphasis is put on the quantitative
assessment of the relation of costs and environmental impacts. In conventional LCA an assessment of environmental impact categories
is often made by normalization with inhabitant equivalents. This is necessary to be able to compare the different environmental
impact categories, because of each different unit. For the proposed eco-efficiency analysis, the costs of products or processes
are also normalized with adapted gross domestic product figures.
Results and Discussion The ratio between normalized environmental impact categories and normalized costs (RE,C) is used for the graphical presentation of the results in an eco-efficiency portfolio. For the interpretation of the results
of an eco-efficiency analysis, it is important to distinguish ratios RE,C which are higher than one from ratios lower than one. In the first case, the environmental impact is higher than the cost
impact, while the inverse is true in the second case. This is very important for defining which kind of improvement is needed
and defining strategic management decisions. The paper shows a statistical evaluation of the RE,C factor based on the results of different eco-efficiency analyses made by BASF. For industries based on large material flows
(e.g. chemicals, steel, metals, agriculture), the RE,C factor is typically higher than one.
Conclusions and Recommendations This contribution shows that LCC and LCA may be combined in a way that they mirror the concept of eco-efficiency. LCAs that
do not consider LCC may be of very limited use for company management. For that very reason, corporations should install a
data management system that ensures equal information on both sides of the eco-efficiency coin. 相似文献
62.
Metz S Naeth G Heinrich PC Müller-Newen G 《The Journal of biological chemistry》2008,283(10):5985-5995
Fusion proteins of the extracellular parts of cytokine receptors, also known as cytokine traps, turned out to be promising cytokine inhibitors useful in anti-cytokine therapies. Here we present newly designed cytokine traps for murine and human leukemia inhibitory factor (LIF) as prototypes for inhibitors targeting cytokines that signal through a heterodimer of two signaling receptors of the glycoprotein 130 (gp130) family. LIF signals through a receptor heterodimer of LIF receptor (LIFR) and gp130 and induces the tyrosine phosphorylation of STAT3 leading to target gene expression. The analysis of various receptor fusion and deletion constructs revealed that a truncated form of the murine LIF receptor consisting of the first five extracellular domains was a potent inhibitor for human LIF. For the efficient inhibition of murine LIF, the cytokine-binding module of murine gp130 had to be fused to the first five domains of murine LIFR generating mLIF-RFP (murine LIFR fusion protein). The tyrosine phosphorylation of STAT3 and subsequent gene induction induced by human or murine LIF are completely blocked by the respective inhibitor. Furthermore, both inhibitors are specific and do not alter the bioactivities of the closely related cytokines interleukin (IL)-6 and oncostatin M. The gained knowledge on the construction of LIF inhibitors can be transferred to the design of inhibitors for related cytokines such as IL-31, IL-27, and oncostatin M for the treatment of inflammatory and malignant diseases. 相似文献
63.
Fan Y Soller M Flister S Hollmann M Müller M Bello B Egger B White K Schäfer MA Reichert H 《Developmental biology》2005,287(1):61-73
The correct targeting of photoreceptor neurons (R-cells) in the developing Drosophila visual system requires multiple guidance systems in the eye-brain complex as well as the precise organization of the target area. Here, we report that the egghead (egh) gene, encoding a glycosyltransferase, is required for a compartment boundary between lamina glia and lobula cortex, which is necessary for appropriate R1-R6 innervation of the lamina. In the absence of egh, R1-R6 axons form a disorganized lamina plexus and some R1-R6 axons project abnormally to the medulla instead of the lamina. Mosaic analysis demonstrates that this is not due to a loss of egh function in the eye or in the neurons and glia of the lamina. Rather, as indicated by clonal analysis and cell-specific genetic rescue experiments, egh is required in cells of the lobula complex primordium which transiently abuts the lamina and medulla in the developing larval brain. In the absence of egh, perturbation of sheath-like glial processes occurs at the boundary region delimiting lamina glia and lobula cortex, and inappropriate invasion of lobula cortex cells across this boundary region disrupts the pattern of lamina glia resulting in inappropriate R1-R6 innervation. This finding underscores the importance of the lamina/lobula compartment boundary in R1-R6 axon targeting. 相似文献
64.
The distribution and morphology of crustacean cardioactive peptide-immunoreactive neurons in the brain of the locust Locusta migratoria has been determined. Of more than 500 immunoreactive neurons in total, about 380 are interneurons in the optic lobes. These neurons invade several layers of the medulla and distal parts of the lobula. In addition, a small group of neurons projects into the accessory medulla, the lamina, and to several areas in the median protocerebrum. In the midbrain, 12 groups or individual neurons have been reconstructed. Four groups innervate areas of the superior lateral and ventral lateral protocerebrum and the lateral horn. Two cell groups have bilateral arborizations anterior and posterior to the central body or in the superior median protocerebrum. Ramifications in subunits of the central body and in the lateral and the median accessory lobes arise from four additional cell groups. Two local interneurons innervate the antennal lobe. A tritocerebral cell projects contralaterally into the frontal ganglion and appears to give rise to fibers in the recurrent nerve, and in the hypocerebral and ingluvial ganglia. Varicose fibers in the nervi corporis cardiaci III and the corpora cardiaca, and terminals on pharyngeal dilator muscles arise from two subesophageal neurons. Some of the locust neurons closely resemble immunopositive neurons in a beetle and a moth. Our results suggest that the peptide may be (1) a modulatory substance produced by many brain interneurons, and (2) a neurohormone released from subesophageal neurosecretory cells. 相似文献
65.
Heike K. Lotze Karsten Reise Boris Worm Justus van Beusekom Mette Busch Anneli Ehlers Dirk Heinrich Richard C. Hoffmann Poul Holm Charlotte Jensen Otto S. Knottnerus Nicole Langhanki Wietske Prummel Manfred Vollmer Wim J. Wolff 《Helgoland Marine Research》2005,59(1):84-95
Todays Wadden Sea is a heavily human-altered ecosystem. Shaped by natural forces since its origin 7,500 years ago, humans gradually gained dominance in influencing ecosystem structure and functioning. Here, we reconstruct the timeline of human impacts and the history of ecological changes in the Wadden Sea. We then discuss the ecosystem and societal consequences of observed changes, and conclude with management implications. Human influences have intensified and multiplied over time. Large-scale habitat transformation over the last 1,000 years has eliminated diverse terrestrial, freshwater, brackish and marine habitats. Intensive exploitation of everything from oysters to whales has depleted most large predators and habitat-building species since medieval times. In the twentieth century, pollution, eutrophication, species invasions and, presumably, climate change have had marked impacts on the Wadden Sea flora and fauna. Yet habitat loss and overexploitation were the two main causes for the extinction or severe depletion of 144 species (~20% of total macrobiota). The loss of biodiversity, large predators, special habitats, filter and storage capacity, and degradation in water quality have led to a simplification and homogenisation of the food web structure and ecosystem functioning that has affected the Wadden Sea ecosystem and coastal societies alike. Recent conservation efforts have reversed some negative trends by enabling some birds and mammals to recover and by creating new economic options for society. The Wadden Sea history provides a unique long-term perspective on ecological change, new objectives for conservation, restoration and management, and an ecological baseline that allows us to envision a rich, productive and diverse Wadden Sea ecosystem and coastal society. 相似文献
66.
Lutein epoxide cycle, light harvesting and photoprotection in species of the tropical tree genus Inga 总被引:2,自引:0,他引:2
Matsubara S Krause GH Seltmann M Virgo A Kursar TA Jahns P Winter K 《Plant, cell & environment》2008,31(4):548-561
Dynamics and possible function of the lutein epoxide (Lx) cycle, that is, the reversible conversion of Lx to lutein (L) in the light-harvesting antennae, were investigated in leaves of tropical tree species. Photosynthetic pigments were quantified in nine Inga species and species from three other genera. In Inga , Lx levels were high in shade leaves (mostly above 20 mmol mol−1 chlorophyll) and low in sun leaves. In Virola surinamensis , both sun and shade leaves exhibited very high Lx contents (about 60 mmol mol−1 chlorophyll). In Inga marginata grown under high irradiance, Lx slowly accumulated within several days upon transfer to deep shade. When shade leaves of I. marginata were briefly exposed to the sunlight, both violaxanthin and Lx were quickly de-epoxidized. Subsequently, overnight recovery occurred only for violaxanthin, not for Lx. In such leaves, containing reduced levels of Lx and increased levels of L, chlorophyll fluorescence induction showed significantly slower reduction of the photosystem II electron acceptor, Q A , and faster formation as well as a higher level of non-photochemical quenching. The results indicate that slow Lx accumulation in Inga leaves may improve light harvesting under limiting light, while quick de-epoxidation of Lx to L in response to excess light may enhance photoprotection. 相似文献
67.
Many theories of human stereovision are based on feature matching and
the related correspondence problem. In this paper, we present
psychophysical experiments indicating that localized image features
such as Laplacian zerocrossings, intensity extrema, or centroids are
not necessary for binocular depth perception. Smooth one-dimensional
intensity profiles were combined into stereograms with
mirror-symmetric half-images such that these localized image features
were either absent or did not carry stereo information. In a
discrimination task, subjects were asked to distinguish between
stereograms differing only by an exchange of these half-images (ortho-
vs. pseudoscopic stereograms). In a depth ordering task, subjects had
to judge which of the two versions appeared in front. Subjects are
able to solve both tasks even in the absence of the mentioned image
features. The performance is compared to various possible stereo
mechanisms. We conclude that localized image features and the
correspondences between them are not necessary to perceive
stereoscopic depth. One mechanism accounting for our data is
correlation or mean square difference.
Received: 8 February 1994 / Accepted in revised form: 15
September
1994 相似文献
68.
Sorbitol dehydrogenase (EC 1.1.1.14) was isolated from bovine brain and purified 3,000-fold to apparent homogeneity, as judged by polyacrylamide gel electrophoresis. The purified enzyme had a specific activity of 36 units/mg of protein; a molecular weight of 39,000 for each of the four identical subunits and 155,000 for the intact enzyme were determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gel exclusion chromatography, respectively. The presence of one Zn2+ per subunit was confirmed by atom absorption spectroscopy; inactivation of the enzyme by metal-chelating agents points to the essential role that Zn2+ plays in the catalytically competent enzyme. The enzyme is also inactivated by thiol-blocking reagents; with respect to inactivation by sodium pyrophosphate, sorbitol dehydrogenase is different from closely related alcohol dehydrogenase. 相似文献
69.
The effect of light on the metabolism of ammonia was studied by subjecting detached maize leaves to 150 or 1350 mol m–2 s–1 PAR during incubation with the leaf base in 2 mM 15NH4Cl. After up to 60 min, leaves were extracted. Ammonia, glutamine, glycine, serine, alanine, and aspartate were separated by isothermal distillation and ion exchange chromatography. 15N enrichments were analyzed by emission spectroscopy. The uptake of ammonium chloride did not influence CO2 assimilation (8.3 and 17.4 mol m–1 s–1 at 150 and 1350 mol m–2 s–1 PAR, respectively). Leaves kept at high light intensity contained more serine and less alanine than leaves from low light treatments. Within 1 h of incubation the enrichment of ammonia extracted from leaves rose to approximately 20% 15N. In the high light regime the amino acids contained up to 15% 15N, whereas in low light 15N enrichments were small (up to 6%). The kinetics of 15N incorporation indicated that NH3 was firstly assimilated into glutamine and then into glutamate. After 15 min 15N was also found in glycine, serine and alanine. At high light intensity nearly half of the 15N was incorporated in glycine. On the other hand, at low light intensity alanine was the predominant 15N sink. It is concluded that light influences ammonia assimilation at the glutamine synthetase reaction. 相似文献
70.
The nucleotide sequence data reported in this paper have been submitted to the GenBank nucleotide sequence database and have been assigned the accession number M74721. 相似文献