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Indicators for biodiversity and ecosystem services: towards an improved framework for ecosystems assessment 总被引:1,自引:0,他引:1
Christian K. Feld José Paulo Sousa Pedro Martins da Silva Terence P. Dawson 《Biodiversity and Conservation》2010,19(10):2895-2919
Ecosystem assessment and monitoring requires the development and application of suitable indicators, i.e. they need to be
(i) reliable and capable of simplifying complex relationships, (ii) quantifiable and transparent in order to enable an easy
communication, and (iii) fit for the purpose of indication. These requirements are scarcely fulfilled in current ecosystem
assessment and monitoring efforts to address the requirements of international biodiversity conventions. Here we present and
test a set of seven criteria towards an improved framework for ecosystems indication with particular emphasis on the indication
of biodiversity and ecosystem services: purpose of indication, indicator type according to the EEA’s Driver-Pressure-State-Impact-Response
scheme, direct/indirect linkages to biodiversity and ecosystem services, spatial scale and scalability across scales, applicability
of benchmarks/reference values, availability of data and protocols, and applicability of remote sensing. The criteria are
tested using 24 indicators of ecosystem assessment and monitoring at the global, continental and regional scale. Based on
the general trends revealed by our evaluation, we present recommendations to streamline and improve ecosystem indication with
respect to international biodiversity conventions. The implementation of our recommendations does require concerted international
effort, comparable, for instance, to the implementation of the Water Framework Directive in Europe. 相似文献
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Seismic and auditory tuning curves from bullfrog saccular and amphibian papular axons 总被引:1,自引:0,他引:1
Xiaolong Yu Edwin R. Lewis David Feld 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1991,169(2):241-248
We present seismic and auditory frequency tuning curves of individual bullfrog, Rana catesbeiana, saccular and amphibian papilla axons that responded to both seismic and auditory stimuli. In this study we found: 1) most saccular axons respond well to auditory stimuli with moderate signal strength (50-70 dB SPL) as well as to seismic stimuli; 2) most amphibian papilla axons respond well to seismic stimuli as well as to auditory stimuli, and their seismic sensitivities are comparable to those of saccular axons (responding to sinusoidal stimuli with peak accelerations in the range 0.001 to 0.1 cm/S2); 3) the responses to both seismic and auditory stimuli from both saccule and amphibian papilla are tuned, i.e. the strength of the response varies with the frequency of the stimulus; and this tuning is clearly not the result of second order resonance; 4) in individual axons the tuning properties for seismic stimuli often are not the same as those for auditory stimuli, a fact that may provide clues about how the stimulus signal energy is transferred to the hair cells in each case. 相似文献
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Inhibition of early steps of de novo fatty-acid biosynthesis by different xenobiotica 总被引:1,自引:0,他引:1
The importance of the early steps of de novo fatty-acid biosynthesis is discussed in terms of rate-limiting enzymic reactions with respect to their inhibition by xenobiotics. The inhibitory spectra of allicin as an inhibitor of the acetyl-CoA-synthase, two classes of graminicides (cyclohexane-1,3-diones and aryloxyphenoxypropionic acids) as inhibitors of acetyl-CoA-carboxylase, and the two antibiotics cerulenin and thiolactomycin, which affect the condensing step in fatty-acid biosynthesis, are compared. 相似文献
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The influence of cold insoluble globulin on platelet morphological response to substrata 总被引:5,自引:0,他引:5
Light microscopic studies have been carried out on the attachment and morphological responses of washed human platelets in serum-free medium to fibrinogen-coated, collagen-coated and uncoated tissue culture plastic substrata. Platelets were observed to attach to the substratum, extend filipodia and undergo spreading. Subsequently, lysis of platelets occurred. On uncoated tissue culture plastic substrata, the addition of cold insoluble globulin to the incubations had no effect on the above morphological changes. On the other hand, on the protein coated substrata, there was very little platelet spreading or lysis without the addition of cold insoluble globulin. 相似文献
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Kwong CD Clark JL Fowler AT Geng F Kezar HS Roychowdhury A Reynolds RC Maddry JA Ananthan S Secrist JA Shih NY Piwinski JJ Li C Feld B Huang HC Tong X George Njoroge F Arasappan A 《Bioorganic & medicinal chemistry letters》2012,22(2):1160-1164
Compound 1 was identified as a HCV replication inhibitor from screening/early SAR triage. Potency improvement was achieved via modulation of substituent on the 5-azo linkage. Due to potential toxicological concern, the 5-azo linkage was replaced with 5-alkenyl or 5-alkynyl moiety. Analogs containing the 5-alkynyl linkage were found to be potent inhibitors of HCV replication. Further evaluation identified compounds 53 and 63 with good overall profile, in terms of replicon potency, selectivity and in vivo characteristics. Initial target engagement studies suggest that these novel carbanucleoside-like derivatives may inhibit the HCV replication complex (replicase). 相似文献
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