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101.
Controllable storage and release of solar energy has always been a highlighted scientific issue for its benefit of mankind. Solar thermal fuels (STFs) supply a closed cycle and renewable energy‐storage strategy by transforming solar energy into chemical energy stored in the conformation of molecular isomers, such as cis/trans‐azobenzene, and releasing it as heat under various stimuli. Although the potential high energy density of the STFs which are based on the hybrids of azobenzene derivatives and carbon nanomaterials has been reported the solvent‐assistant charging hinders their practicability. In this study, a solid‐state STF device is designed and fabricated by compositing one photoliquefiable azobenzene (PLAZ) derivative with a flexible fabric template. The photoinduced phase transition of the PLAZ derivative enables the charging of the flexible STFs to be totally solvent‐free. Interestingly, the energy‐storage capacity (energy density ≈201 J g?1) of flexible PLAZ STFs has been improved by the soft fabric template. The exothermic situation is monitored with one infrared camera, which shows 4 °C temperature difference between charged and discharged samples under blue light stimulus. The flexible STFs are may be used in practice as heating equipment.  相似文献   
102.
藕莲有性繁殖栽培   总被引:2,自引:0,他引:2  
根据莲(Nelumbo nucifera)生物学特性,既可用藕作种进行无性繁殖,也可用种子播种进行有性繁殖。藕莲在我国有数千年的栽培历史,但素以无性系栽培。尚未见到有性繁殖栽培的报道。作者自1980年起进行了有性繁殖栽培试验。    相似文献   
103.
Selenite and ebselen supplementation has been shown to possess anti-cataract potential in some experimental animal models of cataract, however, the underlying mechanisms remain unclear. The present study was designed to evaluate the anti-cataract effects and the underlying mechanisms of selenite and ebselen supplementation on galactose induced cataract in rats, a common animal model of sugar cataract. Transmission electron microscopy images of lens fiber cells (LFC) and lens epithelial cells (LEC) were observed in d-galactose-induced experimental cataractous rats treated with or without selenite and ebselen, also redox homeostasis and expression of proteins such as selenoprotein R (SELR), 15kD selenoprotein (SEP15), superoxide dismutase 1 (SOD1), catalase (CAT), β-crystallin protein, aldose reductase (AR) and glucose-regulated protein 78 (GRP78) were estimated in the lenses. The results showed that d-galactose injection injured rat lens and resulted in cataract formation; however, selenite and ebselen supplementation markedly alleviated ultrastructural injury of LFC and LEC. Moreover, selenite and ebselen supplementation could mitigate the oxidative damage in rat lens and increase the protein expressions of SELR, SEP15, SOD1, CAT and β-crystallin, as well as decrease the protein expressions of AR and GRP78. Taken together, these findings for the first time reveal the anti-cataract potential of selenite and ebselen in galactosemic cataract, and provide important new insights into the anti-cataract mechanisms of selenite and ebselen in sugar cataract.  相似文献   
104.
The function of NS4B is incompletely understood. The aim of the study is to understand the influence of NS4B on anti-viral response. After cell line stably expressing NS4B established, the influence of IFN-alpha of different concentration on VSV was studied using plaque assay; cell expression profiling caused by NS4B was studied using DNA microarray, and the IFNGR1 fluorescence intensity was analyzed. Our data showed that HCV-NS4B could suppress immuno-associated gene expression, in particular, IFN-gamma receptor signal transduction-related genes. Taken together, NS4B could play some roles in HCV resistance to IFN therapy.  相似文献   
105.
Five new guaiane sesquiterpenes, 1 – 5 , were isolated from the culture broth of the endophytic fungus Xylaria sp. YM 311647, isolated from Azadirachta indica A. Juss . The structures of these compounds were elucidated on the basis of spectroscopic analyses, and their inhibitory activities against five pathogenic fungi were evaluated. All guaiane sesquiterpenes showed moderate or weak antifungal activities in a broth microdilution assay.  相似文献   
106.
Zhu L  Zhang W  Elnatan D  Huang B 《Nature methods》2012,9(7):721-723
In super-resolution microscopy methods based on single-molecule switching, the rate of accumulating single-molecule activation events often limits the time resolution. Here we developed a sparse-signal recovery technique using compressed sensing to analyze images with highly overlapping fluorescent spots. This method allows an activated fluorophore density an order of magnitude higher than what conventional single-molecule fitting methods can handle. Using this method, we demonstrated imaging microtubule dynamics in living cells with a time resolution of 3 s.  相似文献   
107.
Agarose coated gigaporous polystyrene microspheres were evaluated as a novel matrix for immobilized-metal affinity chromatography (IMAC). With four steps, nickel ions were successfully immobilized on the microspheres. The gigaporous structure and chromatographic properties of IMAC medium were characterized. A column packed with the matrix showed low column backpressure and high column efficiency at high flow velocity. Furthermore, this matrix was used for purifying superoxide dismutase (SOD), which was expressed in Escherichia coli (E. coli) in submerged fermentation, on an Äkta purifier 100 system under different flow velocities. The purity of the SOD from this one-step purification was 79% and the recovery yield was about 89.6% under the superficial flow velocity of 3251 cm/h. In conclusion, all the results suggested that the gigaporous matrix has considerable advantages for high-speed immobilized-metal affinity chromatography.  相似文献   
108.
Extracellular matrix (ECM) molecules constitute a "niche" that modulates the migration, proliferation, and differentiation of neural stem/progenitor cells (NSPCs). The glycoprotein Tenascin-R (TN-R) is an ECM molecule, comprising multiple domains. Either the whole TN-R molecule or its distinct domains has been demonstrated to play a very important role in the developing central nervous system. However, little is known about the effect of the TN-R domain on NSPCs, especially NSPC migration. In the present study, we first show that both TN-R domains epidermal growth factor-like repeat (EGFL) and fibronectin type III (FN)6-8 can inhibit the NSPCs migration from neurospheres in vitro. Furthermore, both the EGFL and FN6-8 domains affect the distribution of neurons generated from neurospheres, indicating that EGFL and FN6-8 domains inhibit the motility of neurons generated from neurospheres. These results suggest that TN-R has an inhibitory effect on NSPCs migration.  相似文献   
109.
葛洲坝枢纽下游白鲟性腺发育的初步观察   总被引:2,自引:0,他引:2  
白鲟Psephurus gladius(Martens)是我国特有的稀珍鱼类,近年来对其生物学做了一些初步的研究。鉴于它的种群较小,在学术上具有较为重要的价值,所以,长江兴修水利工程以后对其资源的影响及资源保护和增殖问题,特别是聚集于坝下江段的白鲟亲鱼性腺能否发育成熟等问题,和中华鲟一样引起了水产科学工作者的普遍关注。    相似文献   
110.
Receptor activator of nuclear factor-kappa B (RANK) and its ligand, RANKL play critical roles in bone re-modeling, immune function, vascular disease and mammary gland development. To study the interaction of RANK and RANKL, we have expressed both extracellular domain of RANK and ectodomain of RANKL using Escherichia coli expression system. RANK was expressed as an inclusion body first which properly refolded later, while RANKL was initially produced as a GST fusion protein, after which the GST was removed by enzyme digestion. Soluble RANK existed as a monomer while RANKL was seen as a trimer in solution, demonstrated by gel filtration chromatography and cross-linking experiment. The recombinant RANK and RANKL could bind to each other and the binding affinity of RANKL for RANK was measured with surface plasmon resonance technology and KD value is about 1.09 × 10−10 M.  相似文献   
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