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991.
Zhitao Xu X. G. Ming Wenyan Song Lina He Miao Li 《Systemic Practice and Action Research》2014,27(2):141-164
Quite often over the last decade, heavy equipment manufacturers are trying to improve their project management performance with the use of effective project management methods. However, the challenges encountered aren’t isolated problems and a systemic approach is required. This paper exemplifies how a systemic approach can be applied to heavy equipment manufacturing project (HEMP) management, through of a multifaceted vision. The findings present in the paper are based on a two-year case study in a metallurgic equipment manufacturing enterprise in China. Based on the analysis of HEMP management problems and the contributions on systemic approach application in project management, the paper enriches existing theory by: (1) interpreting the HEMP management system with the top-down disassembly method; (2) developing the collaborative project management approach with a systems view highlighting the project characteristics management and inter-departmental collaboration; (3) making suggestions for systemic approach application in project management. For practitioners and researchers, the findings are particularly meaningful for manufacturing project management and systemic approach application. 相似文献
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Understanding complex physical systems through the use of simulations often takes on a narrative character. That is, scientists using simulations seek an understanding of processes occurring in time by generating them from a dynamic model, thereby producing something like a historical narrative. This paper focuses on simulations of the Diels-Alder reaction, which is widely used in organic chemistry. It calls on several well-known works on historical narrative to draw out the ways in which use of these simulations mirrors aspects of narrative understanding: Gallie for “followability” and “contingency”; Mink for “synoptic judgment”; Ricoeur for “temporal dialectic”; and Hawthorn for a related dialectic of the “actual and the possible”. Through these reflections on narrative, the paper aims for a better grasp of the role that temporal development sometimes plays in understanding physical processes and of how considerations of possibility enhance that understanding. 相似文献
995.
Archive for History of Exact Sciences - Adolf Hurwitz’s estate contains a note from the early 1880s on the converse to Riemann’s proof of the functional equation for the zeta-function;... 相似文献
996.
Yue Shi Guang Yang Jia Yu Lina Yu Ruth Westenbroek William A. Catterall Lisa Juntti-Berggren Per-Olof Berggren Shao-Nian Yang 《Cellular and molecular life sciences : CMLS》2014,71(7):1289-1303
Apolipoprotein CIII (ApoCIII) not only serves as an inhibitor of triglyceride hydrolysis but also participates in diabetes-related pathological events such as hyperactivation of voltage-gated Ca2+ (CaV) channels in the pancreatic β cell. However, nothing is known about the molecular mechanisms whereby ApoCIII hyperactivates β cell CaV channels. We now demonstrate that ApoCIII increased CaV1 channel open probability and density. ApoCIII enhanced whole-cell Ca2+ currents and the CaV1 channel blocker nimodipine completely abrogated this enhancement. The effect of ApoCIII was not influenced by individual inhibition of PKA, PKC, or Src. However, combined inhibition of PKA, PKC, and Src counteracted the effect of ApoCIII, similar results obtained by coinhibition of PKA and Src. Moreover, knockdown of β1 integrin or scavenger receptor class B type I (SR-BI) prevented ApoCIII from hyperactivating β cell CaV channels. These data reveal that ApoCIII hyperactivates β cell CaV1 channels through SR-BI/β1 integrin-dependent coactivation of PKA and Src. 相似文献
997.
Activation of stress signalling pathways enhances tolerance of fungi to chemical fungicides and antifungal proteins 总被引:1,自引:0,他引:1
Brigitte M. E. Hayes Marilyn A. Anderson Ana Traven Nicole L. van der Weerden Mark R. Bleackley 《Cellular and molecular life sciences : CMLS》2014,71(14):2651-2666
Fungal disease is an increasing problem in both agriculture and human health. Treatment of human fungal disease involves the use of chemical fungicides, which generally target the integrity of the fungal plasma membrane or cell wall. Chemical fungicides used for the treatment of plant disease, have more diverse mechanisms of action including inhibition of sterol biosynthesis, microtubule assembly and the mitochondrial respiratory chain. However, these treatments have limitations, including toxicity and the emergence of resistance. This has led to increased interest in the use of antimicrobial peptides for the treatment of fungal disease in both plants and humans. Antimicrobial peptides are a diverse group of molecules with differing mechanisms of action, many of which remain poorly understood. Furthermore, it is becoming increasingly apparent that stress response pathways are involved in the tolerance of fungi to both chemical fungicides and antimicrobial peptides. These signalling pathways such as the cell wall integrity and high-osmolarity glycerol pathway are triggered by stimuli, such as cell wall instability, changes in osmolarity and production of reactive oxygen species. Here we review stress signalling induced by treatment of fungi with chemical fungicides and antifungal peptides. Study of these pathways gives insight into how these molecules exert their antifungal effect and also into the mechanisms used by fungi to tolerate sub-lethal treatment by these molecules. Inactivation of stress response pathways represents a potential method of increasing the efficacy of antifungal molecules. 相似文献
998.
为研究复杂工况下中介轴承的动力学特性,针对外圈支承于低压转子轴颈,内圈支承于高压转子轴颈支承形式的中介轴承的工作特点,应用LS-DYNA建立了中介圆柱滚子轴承动力学模型,开展动力学仿真。该模型以显式算法为基础,在充分考虑中介轴承转速、旋转方向、负载、接触及摩擦的条件下,基于动力学仿真模型,分析了中介轴承应力水平随内外圈旋转方向、内外圈转速及径向外载荷变化的规律。分析结果表明:在内外圈反向旋转以及外圈转速增加的情况下中介轴承的振动更为平稳,而在径向外载荷增大的情况下,中介轴承的振动更加剧烈。仿真结果验证了模型的正确性,为中介轴承故障诊断提供了有益参考。 相似文献
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