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101.
Liu Jiankang Jiang Yujing Han Wei Sakaguchi Osamu 《Bulletin of Engineering Geology and the Environment》2021,80(3):2283-2305
Bulletin of Engineering Geology and the Environment - Rock mass quality assessment has a vital influence on the excavation of tunnels and caverns in rock mass. For this purpose, extensive field... 相似文献
102.
Kenta Takahashi Naru Shiraishi Risa Ishiko-Uzuka Takahisa Anada Osamu Suzuki Hiroshi Masumoto Keiichi Sasaki 《International journal of molecular sciences》2015,16(3):5779-5788
Dental implants are widely used and are a predictable treatment in various edentulous cases. Occlusal overload may be causally related to implant bone loss and a loss of integration. Stress concentrations may be diminished using a mechanobiologically integrated implant with bone tissue. The purpose of this study was to investigate the biomechanical behavior, biocompatibility and bioactivity of a Ti-Nb-Sn alloy as a dental implant material. It was compared with cpTi. Cell proliferation and alkaline phosphatase (ALP) activity were quantified. To assess the degree of osseointegration, a push-in test was carried out. Cell proliferation and ALP activity in the cells grown on prepared surfaces were similar for the Ti-Nb-Sn alloy and for cpTi in all the experiments. A comparison between the Ti-Nb-Sn alloy implant and the cpTi implant revealed that no significant difference was apparent for the push-in test values. These results suggest that implants fabricated using Ti-Nb-Sn have a similar biological potential as cpTi and are capable of excellent osseointegration. 相似文献
103.
Kazuo Kato Osamu Miura 《IEEJ Transactions on Electrical and Electronic Engineering》2014,9(3):288-293
The spatial frequency contained in visual objects is known to affect human psychophysiology. In our previous study, we showed that event‐related potentials are affected by spatial frequency during a simple calculation task. In that study, however, we did not investigate the contribution of oscillatory neural activities. The purpose of the present study is to characterize the changes in oscillatory neural activity associated with cognitive processes, and to investigate how these signals are affected by the spatial frequency of a visual stimulus during simple calculation tasks. We investigate these issues by analyzing our previously collected electroencephalography (EEG) dataset using the same visual stimulus, tasks, subjects, and EEG recordings. In that study, four types of vertically striped visual stimuli were used. The visual stimuli contained embedded numbers (from 0 to 9) that possessed the following frequency (f) characteristics: white noise, 1/f, 1/f2, and 1/f3. The subjects were instructed to perform two tasks: ‘add numbers’ (addition task) and ‘do not add numbers’ (reference task). EEG data were recorded, and event‐related synchronization (ERS) and desynchronization (ERD) for each visual stimulus were analyzed on the basis of the intertrial variances of wavelet coefficients for theta, alpha, low‐beta, and gamma band activity. Eight healthy men (21–23 years) were recruited to participate in the study. Our results suggest the presence of a frequency discrimination function in the theta band activity in the fronto‐central area at the latency of 198 ms during the addition task. The alpha‐band ERD during completion of the reference task also showed a spatial frequency dependency. This phenomenon was observed in the left temporal‐parietal area at a latency of 376 ms, and is thought to be related to the perceptual filter. We conclude that the observed changes in oscillatory neural activity associated with cognitive processes are affected by spatial frequency. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
104.
Fujita J Yamane Y Fukuda H Kizaki Y Wakabayashi S Shigeta S Suzuki O Ono K 《Journal of Bioscience and Bioengineering》2003,95(4):348-353
We identified three types of acid phosphatase (ACP-I, ACP-II, and ACP-III) produced by Aspergillus oryzae in a submerged culture using only phytic acid as the phosphorous substrate. The optimum pH for the activities of the three enzymes was in the range of 4.5 to 5.5. Analysis of the substrate specificities of these enzymes revealed that ACP-I and ACP-III were acid phosphatases, and ACP-II was a phytase. These enzymes were produced during different periods of mycelial growth: ACP-II was produced during the early phase of cultivation (around 24 h), and ACP-I was produced between 24 to 72 h. ACP-III was detected after the production of ACP-I and ACP-II had ceased. The release of phosphate from phytic acid was expected to be due to the cooperative hydrolysis of these enzymes. 相似文献
105.
The thermo-emf ΔV of the touching p- and n-type Cu/Bi-Te/Cu composites with different thicknesses of t
Bi-Te and t
Cu was measured as a function of time by alternating the temperature difference ΔT at periods of T = 20, 60, 120, 240 and ∞ sec, where t
Bi-Te was varied from 0.1 to 2.0 mm and t
Cu from 0 to 4.0 mm. As a result, ΔV changes significantly with t
Bi-Te, t
Cu and T. The effective thermo-emf ΔV
eff increases significantly with an increase of 1/T and exhibited a local maximum at 1/T = 1/240 s−1. The resultant | α | and the effective temperature difference ΔT
eff were increased significantly by optimizing t
Bi-Te and t
Cu at 1/T = 1/240 s−1. The power generation ΔW
eff (= ΔV
eff2/4R
calc) estimated using the measured ΔV
eff and calculated R
calc also exhibited a local maximum at 1/240 s−1 for an optimum combination of t
Bi-Te = 0.1 mm and t
Cu = 2.0 mm, so that the maxima ΔW
eff at 1/T = 1/240 s−1 for the p- and n-type composites were 2.28 and 2.92 times higher than those obtained at 1/T = 0 s−1. This significant increase in ΔW
eff is owing to both the increase in ΔT
eff and the increase in ZT due to the increase in |α|. The power generation was thus found to be enhanced significantly by imposing the alternating
temperature gradients on touching Cu/Bi-Te/Cu composites. 相似文献
106.
Fuminori Tanihara Maki Hirata Nhien Thi Nguyen Osamu Sawamoto Takeshi Kikuchi Takeshige Otoi 《International journal of molecular sciences》2021,22(5)
Xenoantigens cause hyperacute rejection and limit the success of interspecific xenografts. Therefore, genes involved in xenoantigen biosynthesis, such as GGTA1, CMAH, and B4GALNT2, are key targets to improve the outcomes of xenotransplantation. In this study, we introduced a CRISPR/Cas9 system simultaneously targeting GGTA1, CMAH, and B4GALNT2 into in vitro-fertilized zygotes using electroporation for the one-step generation of multiple gene-edited pigs without xenoantigens. First, we optimized the combination of guide RNAs (gRNAs) targeting GGTA1 and CMAH with respect to gene editing efficiency in zygotes, and transferred electroporated embryos with the optimized gRNAs and Cas9 into recipient gilts. Next, we optimized the Cas9 protein concentration with respect to the gene editing efficiency when GGTA1, CMAH, and B4GALNT2 were targeted simultaneously, and generated gene-edited pigs using the optimized conditions. We achieved the one-step generation of GGTA1/CMAH double-edited pigs and GGTA1/CMAH/B4GALNT2 triple-edited pigs. Immunohistological analyses demonstrated the downregulation of xenoantigens; however, these multiple gene-edited pigs were genetic mosaics that failed to knock out some xenoantigens. Although mosaicism should be resolved, the electroporation technique could become a primary method for the one-step generation of multiple gene modifications in pigs aimed at improving pig-to-human xenotransplantation. 相似文献
107.
Somiya K Beyersdorf P Arai K Sato S Kawamura S Miyakawa O Kawazoe F Sakata S Sekido A Mio N 《Applied optics》2005,44(16):3179-3191
We report on our prototype experiment that uses a 4-m detuned resonant sideband extraction interferometer with suspended mirrors, which has almost the same configuration as the next-generation, gravitational-wave detectors. We have developed a new control scheme and have succeeded in the operation of such an interferometer with suspended mirrors for the first time ever as far as we know. We believe that this is the first such instrument that can see the radiation pressure signal enhancement, which can improve the sensitivity of next-generation gravitational-wave detectors. 相似文献
108.
109.
Fat-Halla Nabil Takasugi Takayuki Izumi Osamu 《Metallurgical and Materials Transactions A》1979,10(9):1341-1349
The deformation up to fracture at 150 K was undertaken on α-β brass two-phase bicrystals. The variation of the slip systems
during the proceeding deformation was studied and explained on the basis of incompatible stresses. The normal stress-strain
curves were analyzed for various types of bicrystals and the bending that appeared in the specimens when unloaded was explained
with respect to the occurrence of the Bauschinger effect in the α phase. Fracture modes other than those observed at room
temperature were present. The results, and other minor problems, were discussed. 相似文献
110.
Shimizu M Adachi S Masuda M Kozawa O Moriwaki H 《Molecular nutrition & food research》2011,55(6):832-843
Recent studies indicate that receptor tyrosine kinases (RTKs), which play important roles in cell proliferation, are one of the possible targets of green tea catechins (GTCs) in cancer cell growth inhibition. (-)-Epigallocatechin-3-gallate (EGCG), the major catechin in green tea, inhibits cell proliferation and induces apoptosis in various types of cancer cells, including colorectal cancer and hepatocellular carcinoma cells, by blocking the activation of the epidermal growth factor receptor (EGFR) family of RTKs. EGCG inhibits the activation of insulin-like growth factor-1 receptor (IGF-1R) and VEGFR2, the other members of the RTK family, and this effect is also associated with the anticancer and chemopreventive properties of this agent. EGCG suppresses the activation of EGFR in part by altering membrane lipid organization and causing the subsequent inhibition of the dimerization and activation of this receptor. Preliminary trials have shown that GTCs successfully prevent the development and progression of precancerous lesions, such as colorectal adenomas, without causing severe adverse effects. The present report reviews evidence indicating that GTCs exert anticancer and chemopreventive effects by inhibiting the activation of specific RTKs, especially EGFR, IGF-1R, and VEGFR2, and concludes that targeting RTKs and their related signaling pathways by using tea catechins could be a promising strategy for the prevention of human cancers. 相似文献