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41.
Molecular basis of seasonal time measurement in Arabidopsis 总被引:36,自引:0,他引:36
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风-车-桥耦合系统的车桥气动特性 总被引:2,自引:0,他引:2
采用数值模拟方法对风-车-桥耦合系统的车桥气动特性进行分析研究,模拟计算了不同工况下车辆、桥梁的气动力系数。分析了车桥间相互的气动影响.研究结果表明.车桥耦合系统与桥梁和车辆各自单体相比较,气动力系数差异较大,故建议进行风-车-桥系统耦合振动分析时,车桥气动力系数应考虑车桥间的气动影响. 相似文献
43.
A Critical Assessment of Project Management Methods with Respect to Electronic Government Implementation Challenges 总被引:1,自引:1,他引:0
Demetrios Sarantis Steve Smithson Yannis Charalabidis Dimitris Askounis 《Systemic Practice and Action Research》2010,23(4):301-321
In taking forward both the Government Modernization and the Civil Service Reform agendas, renewed emphasis is being placed
on project management approaches and techniques for achieving objectives more effectively and efficiently. After elaborating
on specific electronic government project implementation challenges and giving an overview of state-of-the-art project management
approaches, the paper examines the weaknesses of three commonly used methods in the light of the e-Government project challenges.
The analysis identifies gaps in the methods, contributing to a better understanding of the factors that lead to success or
failure. The resolution of such methodological limitations could lead to the enhancement of project management methods when
applied to future projects. 相似文献
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Arising from: S. J. Lolle, J. L. Victor, J. M. Young & R. E. Pruitt 434, 505-509 (2005); Lolle et al. reply. Lolle et al. report that loss-of-function alleles of the HOTHEAD (HTH) gene in Arabidopsis thaliana are genetically unstable, giving rise to wild-type revertants. On the basis of the reversion of many other genetic markers in hth plants, they suggested a model in which a cache of extragenomic information could cause genes to revert to the genotype of previous generations. In our attempts to reproduce this phenomenon, we discovered that hth mutants show a marked tendency to outcross (unlike wild-type A. thaliana, which is almost exclusively self-fertilizing). Moreover, when hth plants are grown in isolation, their genetic inheritance is completely stable. These results may provide an alternative explanation for the genome wide non-mendelian inheritance reported by Lolle et al. 相似文献
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