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61.
An Exploratory Framework for the Empirical Measurement of Resilience 总被引:12,自引:1,他引:11
G. S. Cumming G. Barnes S. Perz M. Schmink K. E. Sieving J. Southworth M. Binford R. D. Holt C. Stickler T. Van Holt 《Ecosystems》2005,8(8):975-987
Deliberate progress towards the goal of long-term sustainability depends on understanding the dynamics of linked social and
ecological systems. The concept of social-ecological resilience holds promise for interdisciplinary syntheses. Resilience
is a multifaceted concept that as yet has not been directly operationalized, particularly in systems for which our ignorance
is such that detailed, parameter-rich simulation models are difficult to develop. We present an exploratory framework as a
step towards the operationalization of resilience for empirical studies. We equate resilience with the ability of a system
to maintain its identity, where system identity is defined as a property of key components and relationships (networks) and
their continuity through space and time. Innovation and memory are also fundamental to understanding identity and resilience.
By parsing our systems into the elements that we subjectively consider essential to identity, we obtain a small set of specific
focal variables that reflect changes in identity. By assessing the potential for changes in identity under specified drivers
and perturbations, in combination with a scenario-based approach to considering alternative futures, we obtain a surrogate
measure of the current resilience of our study system as the likelihood of a change in system identity under clearly specified
conditions, assumptions, drivers and perturbations. Although the details of individual case studies differ, the concept of
identity provides a level of generality that can be used to compare measure of resilience across cases. Our approach will
also yield insights into the mechanisms of change and the potential consequences of different policy and management decisions,
providing a level of decision support for each case study area. 相似文献
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Jiaqiang Cai D. Jonathan Bennett Zoran Rankovic Maureen Dempster Xavier Fradera Jonathan Gillespie Iain Cumming William Finlay Mark Baugh Sylviane Boucharens John Bruin Kenneth S. Cameron William Hamilton Jennifer Kerr Emma Kinghorn George McGarry John Robinson Paul Scullion Joost C.M. Uitdehaag Mario van Zeeland Eric Nicolai 《Bioorganic & medicinal chemistry letters》2010,20(15):4447-4450
Starting from previously disclosed equally potent cathepsin K and S inhibitor 4-propyl-6-(3-trifluoromethylphenyl)pyrimidine-2-carbonitrile 1, a novel 2-phenyl-9H-purine-6-carbonitrile scaffold was identified to provide potent and selective cathepsin S inhibitors. 相似文献
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Cytological and fertility tests were performed in F1 male mice derived from different germ-cell stages of male parents treated with cyclophosphamide (350 mg/kg body weight). The objectives of the present experiment were: (I) to determine the sensitivity of the male germ-cell stages to the induction of translocations by the compound, and (2) to characterize translocation configurations in F1 and F2 males, in order to obtain information about the pattern of chromosome breakage induced and its transmission to subsequent generations. Of 508 F1 males studied, 39 were partially sterile. The group of males conceived 8-21 days after treatment contained by far the highest proportion of partially sterile animals (30%). It was also the only group in which totally sterile animals (11%) were found. Of 25 semisterile males from this group, 24 gave evidence of translocations when spermatocytes were scored at diakinesis. The translocation frequencies in F1 derived from treated spermatozoa and spermatocytes were 14 and 1%, respectively. No translocations were detected cytologically in 6 semisterile males derived from treated spermatogonial stages. These results indicate that spermatid stages are especially sensitive to the mutagenic action of cyclophosphamide. In 21 of the 31 semisterile translocation males (68%), the majority of the spermatocytes contained 18 bivalents plus a ring-of-four configuration, indicating that both breakpoints were relatively centrally located; and in several of these males, the frequency of cells with rings was close to 100%. In another 9 F1 males (29%) the predominant multivalent configuration was a chain-of-four, indicating one of the breakpoints to be relatively more terminally located; and in one male (3%), the majority of cells had two unequal bivalents, indicating both breakpoints to be fairly close to the ends of the chromosomes involved. Determination of centromere positions by the use of C-banding showed that chain-of-four configurations in any one male were predominantly of a given type.. 相似文献
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The calibration of bicycle ergometers 总被引:1,自引:0,他引:1
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