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201.
浅析市场经济条件下水资源管理的三大转变 总被引:1,自引:0,他引:1
史寒冰 《科技情报开发与经济》2004,14(6):71-72
在市场经济条件下,水资源管理要实现三大转变:一是由传统防范和利用意识向市场资源型转变,建立起水的资源观、可持续利用观和价值观;二是由行政管水的运行机制向水市场体系转变,逐步建立起市场调节与政府调控相结合的新的管理机制;三是由政出多门的管理体制向水务一体化管理体制转变,建立起“统一、高效、负责”的水务一体化管理体制。 相似文献
202.
韩德宏 《科技情报开发与经济》2004,14(6):83-84
在对山西省水资源开发利用所面临的问题进行剖析的基础上。提出了合理开发地下水资源、拉制水资源污染、发展节水工程和实行水资源的统一管理等科学、合理开发利用水资源的对策。 相似文献
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As a newly developed precision technology, casting-forging complex near net forming process is utilized to produce complex components with a short lead time, low cost and high precision, thus to accelerate the response speed of the market and enhance the competitive power of products. In this paper, the casting-forging complex near net forming process of alternator claw pole was developed and investigated with a combination of experimental and numerical simulation method. Qualified near net workpiece was manufactured, mechanical parameter and relative field information during the forming process was also obtained. While the alternator claw-pole is processed with this technology, the forming force is small, the process is short and the quality of forgings is perfect. Therefore, the complex casting-forging near net forming process of claw-pole is an energy and material saving technology, which will have a vast developing and application prospect in the future. 相似文献
205.
John Davenport Julia Davenport Cheong-Hoong Diong K.H. Low 《Journal of Natural History》2016,50(33-34):2097-2105
The pig-nosed freshwater turtle Carettochelys insculpta Ramsay, 1886 has paddle-shaped foreflippers that resemble those of sea turtles. These turtles exhibit a wide range of swimming capabilities. As well as swimming by the action of synchronized foreflippers alone, they sometimes used alternate hindlimb action at the same time. They could swim by ipsilaterally synchronized action of all four limbs, or by hindlimb action alone (combined with stabilizer/lift function of the foreflippers). The turtles also showed flexibility in bottom-walking. Besides the ipsilaterally synchronized quadrupedal action characteristic of other freshwater turtles, they exhibited a bipedal walking mechanism never previously described. Propelled by alternate action of the hindlimbs, the animals held the head and plastron above the substratum, with the large foreflippers acting to provide anterior lift and stability against roll and yaw. Because both hindlimbs were sometimes off the substratum simultaneously during bipedal locomotion, their duty factors were < 0.5, implying a bipedal run. 相似文献
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Julhash U. Kazi Rohit A. Chougule Tianfeng Li Xianwei Su Sausan A. Moharram Kaja Rupar Alissa Marhäll Mohiuddin Gazi Jianmin Sun Hui Zhao Lars Rönnstrand 《Cellular and molecular life sciences : CMLS》2017,74(14):2679-2688
The type III receptor tyrosine kinase FLT3 is frequently mutated in acute myeloid leukemia. Oncogenic FLT3 mutants display constitutive activity leading to aberrant cell proliferation and survival. Phosphorylation on several critical tyrosine residues is known to be essential for FLT3 signaling. Among these tyrosine residues, Y842 is located in the so-called activation loop. The position of this tyrosine residue is well conserved in all receptor tyrosine kinases. It has been reported that phosphorylation of the activation loop tyrosine is critical for catalytic activity for some but not all receptor tyrosine kinases. The role of Y842 residue in FLT3 signaling has not yet been studied. In this report, we show that Y842 is not important for FLT3 activation or ubiquitination but plays a critical role in regulating signaling downstream of the receptor as well as controlling receptor stability. We found that mutation of Y842 in the FLT3-ITD oncogenic mutant background reduced cell viability and increased apoptosis. Furthermore, the introduction of the Y842 mutation in the FLT3-ITD background led to a dramatic reduction in in vitro colony forming capacity. Additionally, mice injected with cells expressing FLT3-ITD/Y842F displayed a significant delay in tumor formation, compared to FLT3-ITD expressing cells. Microarray analysis comparing gene expression regulated by FLT3-ITD versus FLT3-ITD/Y842F demonstrated that mutation of Y842 causes suppression of anti-apoptotic genes. Furthermore, we showed that cells expressing FLT3-ITD/Y842F display impaired activity of the RAS/ERK pathway due to reduced interaction between FLT3 and SHP2 leading to reduced SHP2 activation. Thus, we suggest that Y842 is critical for FLT3-mediated RAS/ERK signaling and cellular transformation. 相似文献
209.
Luiz A. Rocha Joseph D. DiBattista Tane H. Sinclair-Taylor Michael L. Berumen 《Journal of Natural History》2020,54(15-16):1019-1023
ABSTRACT Here we document three cases of mimicry in coral reef fishes not previously reported in the literature involving two groupers (Epinephelus leucogrammicus and Plectropomus marisrubri) and a soapfish (Diploprion drachi) as mimics, and two wrasses (Larabicus quadrilineatus and Cheilinus quinquecinctus) and a blenny (Meiacanthus nigrolineatus) as models. All three cases are of aggressive mimicry, with a predatory species mimicking a harmless one, and in one of the cases, the mimicry is also Müllerian, where both the predator and harmless species are unpalatable. 相似文献
210.
正Published online:14 March 2014óScience China Press and Springer-Verlag Berlin Heidelberg 2014Erratum to:Chin.Sci.Bull.(2014)59(5–6):528–532DOI 10.1007/s11434-013-0060-1In the original publication of this paper,the first name and the last name of the first author has been documented 相似文献