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991.
992.
The development of organic printed electronics has been expanding to a variety of applications and is expected to bring innovations to our future life. Along with this trend, high performance organic materials with cost-efficient fabrication processes and specific features such as thin, light weight, bendable, and low power consumption are required. A variety of organic materials have been investigated in the development of this field. The basic guidelines for material design and the recent progress of polymer-based organic light-emitting diodes (OLEDs) and organic photovoltaic cells (OPVs) are reported.  相似文献   
993.
Proteinase activity was investigated in malt from various barley lines. Results indicated that the total activity and the activity of each class of proteinase varied among the barley lines tested. Cysteine proteinase activity most closely correlated to the malting quality factors such as content of soluble nitrogen and Kolbach index, which shows the important role of cysteine proteinase in the degradation of storage protein in germinating barley. The zymogram pattern was examined by SDS‐PAGE in the pedigree ‘Hokuiku 27’. The results suggest that the activities of low molecular weight cysteine proteinase have a strong influence on the content of soluble nitrogen and Kolbach index in this pedigree.  相似文献   
994.
Transient receptor potential vanilloid 4 (TRPV4) is a non-selective cation channel that is broadly expressed in different human tissues, including the digestive system, where it acts as a molecular sensor and a transducer that regulates a variety of functional activities. Despite the extensive research to determine the role of this channel in the physiology and pathophysiology of different organs, the unique morphological and functional features of TRPV4 in the esophagus remain largely unknown. Ten years ago, TRPV4 was shown to be highly expressed in esophageal epithelial cells where its activation induces Ca2+-dependent ATP release, which, in turn, mediates several functions, ranging from mechanosensation to wound healing. This review summarizes the research progress on TRPV4, and focuses on the functional expression of TRPV4 in esophageal epithelium and its possible role in different esophageal diseases that would support TRPV4 as a candidate target for future therapeutic approaches to treat patients with these conditions.  相似文献   
995.
In International Fusion Materials Irradiation Facility (IFMIF), intense neutron flux (4.5 × 1017 n/m2 s) with a peak energy of 14 MeV are produced by means of two deuteron beams with a total current of 250 mA and maximum energy of 40 MeV that strike a liquid Li target circulating in a Li loop. Major design requirement is to provide a stable Li jet at a speed of 10–20 m/s with a surface wave amplitude on the Li flow less than 1 mm for handling of an averaged heat flux of 1 GW/m2 under a continuous 10 MW deuterium beam deposition. The target system consists of a target assembly, a replaceable back-plate, a Li main loop and a Li purification loop. In July 2007, Engineering Validation and Engineering Design Activities (EVEDA) started under Broader Approach. In this paper, status of the engineering design of the IFMIF Li target system performed in 2007/2008 is described. The future EVEDA tasks to develop the target system are also summarized.  相似文献   
996.
Bile acids (BAs) are a group of amphiphilic molecules consisting of a rigid steroid core attached to a hydroxyl group with a varying number, position, and orientation, and a hydrophilic side chain. While BAs act as detergents to solubilize lipophilic nutrients in the small intestine during digestion and absorption, they also act as hormones. Farnesoid X receptor (FXR) is a nuclear receptor that forms a heterodimer with retinoid X receptor α (RXRα), is activated by BAs in the enterohepatic circulation reabsorbed via transporters in the ileum and the colon, and plays a critical role in regulating gene expression involved in cholesterol, BA, and lipid metabolism in the liver. The FXR/RXRα heterodimer also exists in the distal ileum and regulates production of fibroblast growth factor (FGF) 15/FGF19, a hormone traveling via the enterohepatic circulation that activates hepatic FGF receptor 4 (FGFR4)-β-klotho receptor complex and regulates gene expression involved in cholesterol, BA, and lipid metabolism, as well as those regulating cell proliferation. Agonists for FXR and analogs for FGF15/19 are currently recognized as a promising therapeutic target for metabolic syndrome and cholestatic diseases.  相似文献   
997.
近50年来,天然气的消耗量大大增加,并且会继续增加以降低主要能源的CO2排放量。随着天然气供应量的增加,为保证其输送的经济性和安全性,开发了高强度大直径焊管,并已成功应用在全球多个地区(如北极地区、地震带和深海海域)。天然气需求的增加对长距离输送管线用钢管提出了新的要求,为此,研究了更为恶劣环境下承受高压和轴向应变的高性能钢管:分析了所开发的高压输气管线用高品质钢管的性能;探讨了承受轴向应变钢管的进一步开发。  相似文献   
998.
A current measuring device applicable to an extra-high voltage power transmission line higher than 500 kV is proposed with preliminary experimental results. It obtains the instantaneous magnetic field ajacent to a transmission wire by measuring the angle of Faraday rotation of a laser beam in a flint glass rod. The laser beam is transmitted and analyzed at a ground potential site, and in the energized part this device has neither insulated conductors nor active elements. An experimental laser current transformer yielded a sensitivity of 66 mV per 100 A and good linearity. Various sources of error and modifications are discussed.  相似文献   
999.
Lipases from Candida rugosa (CRL) and Pseudomonas cepacia (PCL) were co-lyophilized with cyclic oligoethers including four crown ethers and nine cyclodextrins (CyDs), and their transesterification activity and enantioselectivity in organic solvents were evaluated. The PCL co-lyophilized with each additive showed simultaneously enhanced enzyme activity and enantioselectivity when compared to the native lipase lyophilized from buffer alone; in contrast, such enhancement was not observed for the co-lyophilized CRL. Among the cyclic oligoethers examined, permethylated betaCyD (Me1.78betaCyD), as the most suitable additive, was used for the optimization of both the co-lyophilized PCL preparation and reaction conditions by determining the effects of varying the additive/lipase ratio, aqueous pH, the nature of organic solvents, and temperature. The initial rate determined for the transesterification between racemic 2,2-dimethyl-1,3-dioxolane-4-methanol and vinyl butyrate in diisopropyl ether at 30 degrees C increased by up to 17-fold and the enantioselectivity represented by E could be doubled. While there was an inverse correlation between temperature and enantioselectivity, with the Me1.78betaCyD-PCL co-lyophilizate, the reaction rate even at 0 degrees C was much higher than that at higher temperatures in the native PCL-catalyzed reaction. Hence, this method seems to be of practical use for the large-scale production of optically active compounds.  相似文献   
1000.
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