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691.
Aquaporins are implicated in a wide variety of plant physiological processes, although the mechanisms involved in their regulation are not fully understood. To gain further insight into the regulatory factors involved in this process, we used a yeast two-hybrid system to screen for potential binding partners to the Arabidopsis tonoplast intrinsic protein (TIP) AtTIP1;1. This was the first protein identified to be associated with high water permeability in vacuolar membranes from Arabidopsis thaliana. Using ... 相似文献
692.
解构中国少数民族:去东方学化还是再东方学化 总被引:1,自引:0,他引:1
潘蛟 《广西民族大学学报》2009,(2)
自20世纪90年代以来,中国的民族识别或中国政府对其境内少数民族的政治构建遭到了来自西方的中国研究专家们的解构。在这种后殖民批评式的拆解中,中国的少数民族承认和包容政治被当做了对于少数民族的歧视和排斥政治,中国的世居少数民族问题被搅混成了侨散居少数族裔问题,中国的民族识别问题被当做了内殖民主义或内东方学问题。然而,刀诡的是,尽管在其笔下中国少数民族被中国政府当做了内部的东方,但是,值得注意的是,这种把当代中国少数民族承认政治东方专制主义化的取向,在中国学界不仅没有激起有力的批判性回应,反倒生成了许多诸如对少数民族去政治化、民族共治、唯个体公民权利论之类西方学畅想! 相似文献
693.
The effects of Cl-concentration,temperature,pH,flow velocity,soluble oxygen content of seawater and anodic current on the potential of high purity zinc and Zn-Al-Cd reference electrodes were investigated. The results show that the investigated metal materials are liable to establish stable potential and act as reference electrodes in seawater,diluted seawater and urban tap water. Cl-concentration,temperature,seawater flow velocity and anodic current have an obvious effect on zinc potentials. However,seawate... 相似文献
694.
To better understand variation of Holocene Chinese mandiblular morphology, a study was conducted on 23 metric traits of Neolithic (n=54), Bronze-Iron Ages (n=184) and modern (n=92) adult male mandibles from northern China. Results indicate that the linear characters of these Chinese mandibles evolved in the past 7000 years. From the Neolithic to Bronze-Iron Ages to present day, the overall size of mandibles decreased. The linear characters of the mandiblular features varied between different time periods. The decrease of thickness and height of the mandibular corpus primarily occurred during the Neolithic to Bronze-Iron Ages. The decrease in main size was during the Bronze-Iron Ages to present day. It is possible that mandibles became thinner before the overall size decreased. Comparisons also indicate that the bottom part of the face may have decreased more greatly in breadth than the upper portion. The decrease in mandible size may be associated with changes in climate and diet, and with changes in the craniums size. 相似文献
695.
焦黎 《新疆师范大学学报(自然科学版)》1999,(3)
环境质量评价指数方法是认识和研究环境及对环境质量优劣进行定量描述的一种科学方法。本文通过对此方法的比较分析,提出其在具体实践应用中所存在的问题与不足,同时提出了解决问题的途径和办法。 相似文献
696.
焦黎 《新疆师范大学学报(自然科学版)》2001,20(4):63-67
旅游业可持续发展的实质,就是要求其与自然、化和人类生存环境成为一个整体,发展旅游业要立足长远,克服短期行为,尤其是要体现和发挥政府的主导作用。章通过对塔城地区旅游业持续发展的主要影响因素和旅游业可持续发展驱动因素的分析,进而提出塔城地区旅游业可持续发展的对策与建议。 相似文献
697.
在结构设计中,往往把坑道围岩的稳定性转化为对支护结构的荷载,即围岩压力来处理,围岩类别不同,相应的围岩压力也不同.文章对公路隧道围岩的稳定性、围岩的压力及分布范围进行了分析. 相似文献
698.
It has been found that high-order deformation (e.g.β6) can have important effects on the structures of superheavy nuclei. In the present work, we investigate octupole deformation effects on superheavy nuclei with an improved potential-energy-surface (PES) calculation by including reflection-asymmetric deformations in a space of (β2 ,β3 ,β4 , β5). The calculations give various deformations including highly deformed (β2 ≈ 0.4) and superdeformed (β2 ≈ 0.7) shapes. The octupole-deformation degree of freedom mainly affects the fission barrier beyond the second minimum of PES. 相似文献
699.
<正> In this paper,a two-scale finite element approach is proposed and analyzed for approximationsof Green's function in three-dimensions.This approach is based on a two-scale finite elementspace defined,respectively,on the whole domain with size H and on some subdomain containing singularpoints with size h (h H).It is shown that this two-scale discretization approach is very efficient.In particular,the two-scale discretization approach is applied to solve Poisson-Boltzmann equationssuccessfully. 相似文献
700.
In order to develop an efficient identification method for Fallopia plants and drugs, molecular analysis of the partial matK gene sequences was performed on 6 Fallopia species. Based on the matK sequences, a phylogenetic tree was constructed, which showed that different populations of inter- and intra-species could
be specified and distinguished. The matK gene sequences of the 6 Fallopia species were all found to be of 1 271 bp in length, with some nucleotide variations throughout the entire sequences. The
nucleotide difference at position 1 041 could distinguish F. denticulata from others, while specific nucleotide at position 1 154 became identification markers for F. aubertii. Moreover, four specific marker sites for F. multiflora var. ciliinerve at positions 216, 224, 1 060 and 1 179, seven for F. convolvulus at 318, 765, 772, 874, 936, 952 and 1 036, and seven for F. dentate alata at 111, 192, 366, 450, 457, 1 032 and 1 074 were also observed. By detecting the marker nucleotides and analyzing the phylogenetic
relationship, the botanical origins of five inspected drugs were determined, suggesting that matK sequences can be used for authenticating Fallopia plants and drugs. 相似文献