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排序方式: 共有1895条查询结果,搜索用时 15 毫秒
971.
Hiroshi Kawakami Atsushi Nishikawa Shoki Komada Yuji Yamamoto Jippei Suzuki 《Welding International》2013,27(8):542-549
ABSTRACTRotating tool spot joining in low rotating speed range is investigated in this study. Torque of the motor increased with the decrease in rotating speed of the motor. Joint strength increased significantly with the decrease in rotating speed. Shoulder plug fracture was observed as a characteristic fracture mode under the long joining time and low rotating speed joining conditions and it obtained the large plastic deformation. The rotational motion of the joining interface was similar with the Rankin vortex. The relationship between the joining interface deformation by the external force and the plastic deformability by the friction heat on this joining process was considered from the experimental results. 相似文献
972.
Kazuhiro Mio Shoko Fujimura Masaki Ishihara Masahiro Kuramochi Hiroshi Sekiguchi Tai Kubo Yuji C. Sasaki 《International journal of molecular sciences》2021,22(10)
Serotonin receptors play important roles in neuronal excitation, emotion, platelet aggregation, and vasoconstriction. The serotonin receptor subtype 2A (5-HT2AR) is a Gq-coupled GPCR, which activate phospholipase C. Although the structures and functions of 5-HT2ARs have been well studied, little has been known about their real-time dynamics. In this study, we analyzed the intramolecular motion of the 5-HT2AR in living cells using the diffracted X-ray tracking (DXT) technique. The DXT is a very precise single-molecular analytical technique, which tracks diffraction spots from the gold nanocrystals labeled on the protein surface. Trajectory analysis provides insight into protein dynamics. The 5-HT2ARs were transiently expressed in HEK 293 cells, and the gold nanocrystals were attached to the N-terminal introduced FLAG-tag via anti-FLAG antibodies. The motions were recorded with a frame rate of 100 μs per frame. A lifetime filtering technique demonstrated that the unliganded receptors contain high mobility population with clockwise twisting. This rotation was, however, abolished by either a full agonist α-methylserotonin or an inverse agonist ketanserin. Mutation analysis revealed that the “ionic lock” between the DRY motif in the third transmembrane segment and a negatively charged residue of the sixth transmembrane segment is essential for the torsional motion at the N-terminus of the receptor. 相似文献
973.
Sachiko Matsunaga Yuji Yamasaki Yusuke Toda Ryosuke Mega Kinya Akashi Hisashi Tsujimoto 《International journal of molecular sciences》2021,22(13)
Bread wheat (Triticum aestivum) is less adaptable to high temperatures than other major cereals. Previous studies of the effects of high temperature on wheat focused on the reproductive stage. There are few reports on yield after high temperatures at other growth stages. Understanding growth-stage-specific responses to heat stress will contribute to the development of tolerant lines suited to high temperatures at various stages. We exposed wheat cultivar “Norin 61” to high temperature at three growth stages: seedling–tillering (GS1), tillering–flowering (GS2), and flowering–maturity (GS3). We compared each condition based on agronomical traits, seed maturity, and photosynthesis results. Heat at GS2 reduced plant height and number of grains, and heat at GS3 reduced the grain formation period and grain weight. However, heat at GS1 reduced senescence and prolonged grain formation, increasing grain weight without reducing yield. These data provide fundamental insights into the biochemical and molecular adaptations of bread wheat to high-temperature stresses and have implications for the development of wheat lines that can respond to high temperatures at various times of the year. 相似文献
974.
Roberto Giugliani Ana Maria Martins Torayuki Okuyama Yoshikatsu Eto Norio Sakai Kimitoshi Nakamura Hideto Morimoto Kohtaro Minami Tatsuyoshi Yamamoto Mariko Yamaoka Toshiaki Ikeda Sairei So Kazunori Tanizawa Hiroyuki Sonoda Mathias Schmidt Yuji Sato 《International journal of molecular sciences》2021,22(20)
Enzyme replacement therapy (ERT) improves somatic manifestations in mucopolysaccharidoses (MPS). However, because intravenously administered enzymes cannot cross the blood–brain barrier (BBB), ERT is ineffective against the progressive neurodegeneration and resultant severe central nervous system (CNS) symptoms observed in patients with neuronopathic MPS. Attempts to surmount this problem have been made with intrathecal and intracerebroventricular ERT in order to achieve CNS effects, but the burdens on patients are inimical to long-term administrations. However, since pabinafusp alfa, a human iduronate-2-sulfatase fused with a BBB-crossing anti-transferrin receptor antibody, showed both central and peripheral efficacy in a mouse model, subsequent clinical trials in a total of 62 patients with MPS-II (Hunter syndrome) in Japan and Brazil substantiated this dual efficacy and provided an acceptable safety profile. To date, pabinafusp alfa is the only approved intravenous ERT that is effective against both the somatic and CNS symptoms of patients with MPS-II. This article summarizes the previously obtained preclinical and clinical evidence related to the use of this drug, presents latest data, and discusses the preclinical, translational, and clinical challenges of evaluating, ameliorating, and preventing neurodegeneration in patients with MPS-II. 相似文献
975.
976.
Yuji Aoki 《应用聚合物科学杂志》2008,108(4):2660-2666
Steady‐shear measurements of suspensions of carbon blacks (CB) in polystyrene (PS)/di‐(butyl phthalate) (DBP) solution were investigated as a function of volume fraction (?) of CB to clarify the effect of the primary particle size and the structure of CB aggregates on the rheological properties. The suspensions show a typical shear‐thinning behavior in the range of a shear rate studied. The Casson model was applied to evaluate the viscosity at infinite of shear rate η∞ and the yield stress σy for the suspensions. Relative viscosity η∞/ηm, (ηm: medium viscosity) thus obtained was compared to the high‐frequency viscosity for the ideal hard‐sphere silica suspensions to evaluate the effective volume fraction ?eff of CB aggregates. The ?eff value was larger for the higher‐structure CB with higher DBP absorption value, irrespective of the primary particle size. The yield stress σy had almost the same ?eff dependence for neutral furnace CB/(PS/DBP) suspensions, although it was larger for acetylene black (AcB)/(PS/DBP) suspensions. These results demonstrated that the effective volume fraction is the most important quantity to characterize the CB aggregates on the rheological properties. It was also found that the correction of the medium viscosity changes due to polymer adsorption on the CB surface is important since neutral furnace CB adsorbs PS polymers but AcB hardly adsorbs PS polymers in the solution. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
977.
The synthesis and characterization of linear polyethylene/polyester copolymers produced by olefin cross metathesis and subsequent catalytic hydrogenation are described. The success of the scrambling reaction between 1,4-polybutadiene and unsaturated polyester via olefin cross metathesis was confirmed by 1H NMR. Differential scanning calorimetric (DSC) measurements indicated that the size of the copolymer blocks varied gradually with the exchange ratio. Catalytic hydrogenation of the unsaturated copolymers with different exchange ratios was carried out using Pd–Al2O3. The crystallinity of the resulting hydrogenated polymers depended on the exchange ratios achieved during olefin cross metathesis. This suggests that the unique sequential structure imparted to the unsaturated polymers during metathesis was retained during the hydrogenation process. 相似文献
978.
Cold-active enzymes from cold-adapted bacteria 总被引:5,自引:0,他引:5
Yasutaka Morita Tetsuya Nakamura Quamrul Hasan Yuji Murakami Kenji Yokoyama Eiichi Tamiya 《Journal of the American Oil Chemists' Society》1997,74(4):441-444
The properties of amylase, lipase and protease, excreted by newly isolated bacteria from snow-covered soil, salmon intestine
and crab intestine, have been investigated. One amylase, one lipase, and three proteases have been characterized by shifts
in their apparent optimal activities toward low temperatures and by reductions in their activation energy values. The discovered
enzymes were rapidly inactivated at temperatures above the optimum (30 to 40°C). These results suggest that the enzymes are
cold-active. The best cold-active protease producer, isolated from salmon intestine, has been identified as Flavobacterium balustinum by the analysis of 16S rRNA. The optimal growth temperature of this bacterium was 20°C, but a higher amount of protease activity
was present at 10°C. 相似文献
979.
A cost‐effective acid degumming process produces high‐quality Jatropha oil in tropical monsoon climates 下载免费PDF全文
980.
Wei Wang Bingzhi Chen Lei Zhang Junjie Yan Yuanping Lu Xiaoyin Zhang Yuji Jiang Taju Wu Arend Frans van Peer Shaojie Li Baogui Xie 《International journal of molecular sciences》2015,16(7):16669-16682
Molecular markers and genetic maps are useful tools in genetic studies. Novel molecular markers and their applications have been developed in recent years. With the recent advancements in sequencing technology, the genomic sequences of an increasingly great number of fungi have become available. A novel type of molecular marker was developed to construct the first reported linkage map of the edible and economically important basidiomycete Volvariella volvacea by using 104 structural variation (SV) markers that are based on the genomic sequences. Because of the special and simple life cycle in basidiomycete, SV markers can be effectively developed by genomic comparison and tested in single spore isolates (SSIs). This stable, convenient and rapidly developed marker may assist in the construction of genetic maps and facilitate genomic research for other species of fungi. 相似文献