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111.
The photophysical properties of five blue light-emitting polymers based on spirobifluorene applied in polymer light-emitting diodes (PLED) materials have been studied by quantum chemistry. In order to understand the intrinsic reasons for the different performances displayed by the polymers, we carried out density functional theory (DFT) and Marcus theory investigations on their oligomers in terms of structure and properties stability, absorption and emission properties, and carrier injection and transport properties. Especially, some important parameters which had not been reported to our knowledge were given in this contribution, such as the ionization potentials (IPs), electron affinities (EAs), reorganization energies (λ), k e /k h (the ratio between the electron transfer rate (k e ) and hole transfer rate (k h )), and the radiative lifetimes (τ). The main results indicate that the co-oligomers of PCC-1, PCC-2, and PCC-3 with push-pull interactions produced by the existing D-A segments have better carrier injection and transport properties than the oligomers of PSF and PCF. Especially PCC-2 co-oligomer, its large radiation lifetime (7.46 ns) and well balanced and adequate carrier transport guarantee its champion performance for PLED. The calculated results coincide with the experimental ones. Besides, PNF structurally similar to PCC-2 has similar photoelectric properties to PCC-2 in theory, and the fluorescence emission of PNF co-oligomer is superior to PCC-2 co-oligomer. Therefore, we predict that PNF is a promising candidate for PLED. 相似文献
112.
Jian-Guo Hu Xing-Jun Wu Yi-Fan Feng Gang-ming Xi Ling-Xiao Deng Zhen-Huan Wang Rui Wang Lin Shen Jian-Sheng Zhou He-Zuo Lü 《Neurochemical research》2013,38(3):601-609
The conditioned medium from B104 neuroblastoma cells (B104CM) induces proliferation of oligodendrocyte progenitor cells (OPCs) in vitro. However, the molecular events that occur during B104CM-induced proliferation of OPCs has not been well clarified. In the present study, using OPCs immunopanned from embryonic day 14 Sprague–Dawley rat spinal cords, we explored the activation of several signaling pathways and the expression of several important immediate early genes (IEGs) and cyclins in OPCs in response to B104CM. We found that B104CM can induce OPC proliferation through the activation of the extracellular signal-regulated kinases 1 and 2 (Erk1/2), but not PI3K or p38 MAPK signaling pathways in vitro. The IEGs involved in B104CM-induced OPC proliferation include c-fos, c-jun and Id2, but not c-myc, fyn, or p21. The cyclins D1, D2 and E are also involved in B104CM-stimulated proliferation of OPCs. The activation of Erk results in subsequent expression of IEGs (such as c-fos, c-jun and Id-2) and cyclins (including cyclin D1, D2 and E), which play key roles in cell cycle initiation and OPC proliferation. Collectively, these results suggest that the phosphorylation of Erk1/2 is an important molecular event during OPC proliferation induced by B104CM. 相似文献
113.
Neurochemical Research - Evidence exists reporting that miR-410 may rescue neurological deficits, neuronal injury, and neuronal apoptosis after experimental hypoxic ischemia. This study aimed to... 相似文献
114.
Wei Bao Lei Jin Hai-jing Fu Yong-nian Shen Gui-xia Lu Huan Mei Xin-zhi Cao Hong-sheng Wang Wei-da Liu 《PloS one》2013,8(6)
Background
In recent years, the fungal infectious disease zygomycosis has increased in incidence worldwide, especially among the immunodeficient population. Despite the rates of zygomycosis-related death and deformation being very high, the mechanism(s) by which the fungal pathogens cause these severe manifestations remain unknown.Methods
Using the associated Rhizomucor variabilis species, which can selectively induce cutaneous zygomycosis in otherwise healthy individuals, we investigated the host mechanisms of infection-related responses, including cytokine and chemokine expression as well as contributions of particular T cell subsets. siRNA specifically targeting IL-22,IL-17 and IFN-γ were used to down-regulate expression of those molecules.Results
In mouse models of infection, IL-22 was implicated in development of Rhizomucor spp.-induced skin lesions. In cultured human peripheral blood monocytes, R. pusilluscan, which is often found in immunodeficient patients, induced the production of IL-22, while R. variabilis did not. Moreover, Rhizomucor spp.-induced secretion of Il-22 from CCR6+CCR4+CCR10+ cells was down-regulated by knockdown of IL-22 related signaling receptors, RORC and ARH.Conclusion
Our data strongly suggest that avoidance of IL-22 may be one mechanism by which mucor species produce morbidity and mortality in infected individuals. 相似文献115.
Fang Liu Wenqing Li Darin Ridgway Tingyue Gu Zhongyao Shen 《Biotechnology letters》1998,20(4):345-348
Beet molasses successfully replaced glucose as sole carbon source to produce poly--hydroxybutyrate by a recombinant Escherichia coli strain (HMS174/pTZ18u-PHB). The fermentation with molasses was cheaper than with glucose. The final dry cell weight, PHB content and PHB productivity were 39.5 g/L, 80% (w/w) and 1 g/Lh, respectively, in a 5 L stirred tank fermenter after 31.5 h fed-batch fermentation with constant pH and dissolved O2 content. © Rapid Science Ltd. 1998 相似文献
116.
甘薯(Ipomoea batatas)叶光合作用“午睡”现象初探 总被引:1,自引:0,他引:1
在探讨叶片光合产物水平与光合机构运转关系时,我们曾观测到田间甘薯叶片干重增长速率日变化进程中有明显的中午降低即“午睡”现象(图1)。为了揭示这一现象的形成机理,在人工气候室作了以下一些研究。 相似文献
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Zhijiang Yan Mathieu Delannoy Chen Ling Danielle Daee Fekret Osman Parameswary A. Muniandy Xi Shen Anneke B. Oostra Hansen Du Jurgen Steltenpool Ti Lin Beatrice Schuster Chantal Décaillet Andrzej Stasiak Alicja Z. Stasiak Stacie Stone Maureen E. Hoatlin Detlev Schindler Christopher L. Woodcock Hans Joenje Weidong Wang 《Molecular cell》2010,37(6):865-878