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91.
Lj. Grlić 《Cellular and molecular life sciences : CMLS》1956,12(6):230-231
Résumé Les résultats des dosages parallèles d'acide ascorbique et de carotène dans les feuilles des espèces appartenant à 7 familles ont démontré une tendance à la stabilité de la proportion acide ascorbique/carotène chez les plantes apparentées. La stabilité de cette proportion chez les espèces d'une seule famille est plus marquée que celle de la teneur même des deux substances. Ce fait semble pouvoir confirmer l'idée d'une correlation étroite dans l'action des deux substances en question. 相似文献
92.
Barbez E Kubeš M Rolčík J Béziat C Pěnčík A Wang B Rosquete MR Zhu J Dobrev PI Lee Y Zažímalovà E Petrášek J Geisler M Friml J Kleine-Vehn J 《Nature》2012,485(7396):119-122
The phytohormone auxin acts as a prominent signal, providing, by its local accumulation or depletion in selected cells, a spatial and temporal reference for changes in the developmental program. The distribution of auxin depends on both auxin metabolism (biosynthesis, conjugation and degradation) and cellular auxin transport. We identified in silico a novel putative auxin transport facilitator family, called PIN-LIKES (PILS). Here we illustrate that PILS proteins are required for auxin-dependent regulation of plant growth by determining the cellular sensitivity to auxin. PILS proteins regulate intracellular auxin accumulation at the endoplasmic reticulum and thus auxin availability for nuclear auxin signalling. PILS activity affects the level of endogenous auxin indole-3-acetic acid (IAA), presumably via intracellular accumulation and metabolism. Our findings reveal that the transport machinery to compartmentalize auxin within the cell is of an unexpected molecular complexity and demonstrate this compartmentalization to be functionally important for a number of developmental processes. 相似文献
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介绍了ATM交换网络的发展及其工作原理,提出了共享媒介型ATM交换网络的设计方案,完成了该设计方案的硬件设计和软件编程。最后,对实际电路进行了测试,得到了满意的结果。该电路对ATM技术实用化具有重要意义。 相似文献
97.
Li Y Balédent V Yu G Barišić N Hradil K Mole RA Sidis Y Steffens P Zhao X Bourges P Greven M 《Nature》2010,468(7321):283-285
The elucidation of the pseudogap phenomenon of the high-transition-temperature (high-T(c)) copper oxides-a set of anomalous physical properties below the characteristic temperature T* and above T(c)-has been a major challenge in condensed matter physics for the past two decades. Following initial indications of broken time-reversal symmetry in photoemission experiments, recent polarized neutron diffraction work demonstrated the universal existence of an unusual magnetic order below T* (refs 3, 4). These findings have the profound implication that the pseudogap regime constitutes a genuine new phase of matter rather than a mere crossover phenomenon. They are furthermore consistent with a particular type of order involving circulating orbital currents, and with the notion that the phase diagram is controlled by a quantum critical point. Here we report inelastic neutron scattering results for HgBa(2)CuO(4+δ) that reveal a fundamental collective magnetic mode associated with the unusual order, and which further support this picture. The mode's intensity rises below the same temperature T* and its dispersion is weak, as expected for an Ising-like order parameter. Its energy of 52-56?meV renders it a new candidate for the hitherto unexplained ubiquitous electron-boson coupling features observed in spectroscopic studies. 相似文献
98.
Simona Šarotar-Žižek Borut Milfelner Vesna Čančer 《Systemic Practice and Action Research》2013,26(6):549-560
Social responsibility (SR) includes well-being of all. Improving of SR depends also on measurement of well-being. In organizations it requires a hierarchy/network of requisitely holistic factors and indicators. We regarded several definitions of subjective well-being that take into account multiple dimensions and selected factors to be structured in the multi-criteria model: positive affect, negative affect, and life satisfaction. The article presents results of empirical research of subjective well-being in organizations in Slovenia. The factor analysis and theoretical foundations of the characteristics of subjective well-being factors, determined the importance of the criteria—multiple dimensions of subjective well-being. Data about positive and negative affection were obtained with the ‘Positive Affect Negative Affect Scale’; data about life satisfaction were obtained through the ‘Satisfaction with Life Scale’; thus the local values of alternatives—types of organizations in Slovenia—were measured by using value functions. The level of well-being—the aggregate value of well-being measure was assessed with multi-criteria decision-making methods. One can thus benchmark the well-being performance of organizations, determine the key success and failure factors and benefit from good examples. Results offer information for the interventions to increase the subjective well-being in organizations and thus to attain more SR in organization-internal relations. 相似文献
99.
Li Y Balédent V Barisić N Cho Y Fauqué B Sidis Y Yu G Zhao X Bourges P Greven M 《Nature》2008,455(7211):372-375
The pseudogap region of the phase diagram is an important unsolved puzzle in the field of high-transition-temperature (high-T(c)) superconductivity, characterized by anomalous physical properties. There are open questions about the number of distinct phases and the possible presence of a quantum-critical point underneath the superconducting dome. The picture has remained unclear because there has not been conclusive evidence for a new type of order. Neutron scattering measurements for YBa(2)Cu(3)O(6+delta) (YBCO) resulted in contradictory claims of no and weak magnetic order, and the interpretation of muon spin relaxation measurements on YBCO and of circularly polarized photoemission experiments on Bi(2)Sr(2)CaCu(2)O(8+delta)(refs 12, 13) has been controversial. Here we use polarized neutron diffraction to demonstrate for the model superconductor HgBa(2)CuO(4+delta) (Hg1201) that the characteristic temperature T* marks the onset of an unusual magnetic order. Together with recent results for YBCO, this observation constitutes a demonstration of the universal existence of such a state. The findings appear to rule out theories that regard T* as a crossover temperature rather than a phase transition temperature. Instead, they are consistent with a variant of previously proposed charge-current-loop order that involves apical oxygen orbitals, and with the notion that many of the unusual properties arise from the presence of a quantum-critical point. 相似文献
100.
基于小波变换的数字图像压缩研究 总被引:2,自引:0,他引:2
晏力 《重庆工商大学学报(自然科学版)》2009,26(4):341-345
首先从数学分析的角度研究了小波变换的理论基础,然后从实验角度出发探讨了在Matlab数学分析工具环境下小波变换在数字图像压缩中的应用并分析了应用实例;最后,通过实验说明小波变换理论在数字图像处理中所发挥的重要作用. 相似文献