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951.
Aya Hashimoto Liang‐da Chiu Keigo Sawada Tomohiko Ikeuchi Katsumasa Fujita Masahide Takedachi Yoshinori Yamaguchi Satoshi Kawata Shinya Murakami Eiichi Tamiya 《Journal of Raman spectroscopy : JRS》2014,45(2):157-161
Hydroxyapatite (HA) is synthesized at early stages of bone formation by osteoblasts. Nondestructive observation of early stages of osteoblastic mineralization provides crucial information for biological mechanism of bone formation. Raman microscopy serves as an ideal tool to observe the osteoblastic mineralization process because it shows the chemical information of the sample at a minimally invasive level. In addition, HA is a marker for osteoblastic mineralization, and HA Raman signal is strong enough to identify mineralized spots in osteoblasts. In this research, we visualized the distribution of HA in cultured mouse osteoblasts by Raman imaging and observed the location of the mineralized spots in the culture. We monitored HA Raman signal from osteoblast culture for 3 days after administrating the osteogenic differentiation medium and observed Raman signal associated with HA. We identified mineralized spots of KUSA‐A1 by Raman imaging constructed from the distribution of HA Raman signal. We successfully visualized the distribution of the mineralized spots in the culture of KUSA‐A1. We compared our Raman images with Alizarin red S staining assay, which was a conventional method to evaluate the mineralization process. Raman imaging of the KUSA‐A1 culture visualized the mineralized spots more accurately than Alizarin red S staining assay. Raman imaging of HA serves as a powerful tool to identify the mineralized spots in an in vitro culture of osteogenic lineage cells. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
952.
Shinya Yoshidomi Masahiko Hasumi Toshiyuki Sameshima 《Applied Physics A: Materials Science & Processing》2014,116(4):2113-2118
We report connection conductivity ( \(C_{\rm c}\) ) of adhesive which including \(\hbox {In}_2\hbox {O}_3\) – \(\hbox {SnO}_2\) (ITO) particles developed for fabrication of stacked-type-multi-junction solar cells. The commercial 20- \(\upmu \) m sized ITO particles were heated in vacuum at temperature ranging from 800 to 1,300 \(^{\circ }{\rm C}\) for 10 min to increase \(C_{\rm c}\) . 6.2 wt% ITO particles were dispersed in commercial Cemedine adhesive gel to form 100 samples structured with n-type Si/adhesive/n-type Si (n-Si sample) and p-type Si/adhesive/p-type Si (p-Si sample). Current density as a function of voltage (J–V) characteristics gave \(C_{\rm c}\) . It ranged from 4.3 to 1.0 S/cm \(^2\) for the n-Si sample with 800 \(^{\circ }{\rm C}\) heat-treated ITO particles. Its standard deviation was 0.59 S/cm \(^2\) . On the other hand, it ranged from 2.0 to 0.6 S/cm \(^2\) for the p-Si sample with 800 \(^{\circ }{\rm C}\) heat-treated ITO particles. Its standard deviation was 0.22 S/cm \(^2\) . The distribution of \(C_{\rm c}\) mainly resulted from contact efficiency of ITO particles to substrate. We theoretically estimated that present \(C_{\rm c}\) achieved a low loss of the power conversion efficiency ( \(E_{\rm ff}\) ) lower than 0.3 % in the application of fabrication of multi-junction solar cell with an intrinsic \(E_{\rm ff}\) of 30 % and an open circuit voltage above 1.9 V. 相似文献
953.
Yoshiaki Nishijima Yoshikazu Hashimoto Lorenzo Rosa Jacob B. Khurgin Saulius Juodkazis 《Applied Physics A: Materials Science & Processing》2014,117(2):647-650
We demonstrate the qualitative analysis of surface-enhanced Raman scattering (SERS) intensity and optical extinction by experimentally and numerically. This analytical methods are well matched not only the simple square lattice array of nanostructures, but also the rectangular lattices. We also demonstrate SERS selectivity of modes controlling the optical extinction of excitation and scattering wavelength. Both square lattice and rectangular lattice have similar tendency, but the rectangular lattice structures have much higher selectivity of SERS modes. 相似文献
954.
955.
Kiyoshi Matsumoto Shiro Hashimoto Shinichi Otani Fujitsugu Atnita Jiro Osugi 《合成通讯》2013,43(6):585-590
Dimethylaminomethylation of ketones with bis(dimethyl-amino)methane takes place cleanly in methanol at room temperature in the kiro bar region. 相似文献
956.
Ryoko Yasumura Kumar Dilip Ashtekar Akio Tonouchi Tatsuo Nehira Babak Borhan Masaru Hashimoto 《Tetrahedron》2013
Novel 7-β- and 10-β-hydroxylated congeners of CAF-603 (4 and 5, respectively) were isolated from Trichoderma crassum. Relative configuration of 4 was determined by NOE experiments. Stereochemistry of 7-β-hydroxy group in 5 was established by a combination of vicinal 3JH–H analyses and quantum chemical calculations. Absolute configurations of 4 and 5 were established by observing the Cotton effects of their bis(2-naphthoate) esters. T. crassum also produce known CAF-603 (1), 14-hydroxy and 8,9-β-epoxy derivatives (2 and 3, respectively). Present study first established the absolute configuration of CAF-603 family by taking their biosyntheses into account. Preliminary biological experiments revealed that the molecular target strictly recognizes the β-side of the cycloheptane ring. 相似文献
957.
Masahiko ABE Robert S. SCHECHTER Robert D. SELLIAH Baharuddin SHEIKH William H. WADE 《Journal of Dispersion Science and Technology》2013,34(2):157-172
This paper describes the effect of pH on phase behavior of branched tail EO carboxylate surfactants in electrolyte/ alkane microemulsion system3 which are of possible pertinence to enhanced oil recovery. The pH of the aqueous surfactant solutions was found to have a considerable effect on the salinity requirement for middle phase microemulsion formation. At 70 and 60°C alcohol-free optimal three phase microemulsion systems are formed with all alkanes studied over the entire pH range of 6-12. At lower temperatures and. higher pH values, liquid crystals were found to form in systems which contained lower molecular weight alkanes. 相似文献
958.
Hirokazu Saito Yuki Kaneko Yuki Hashimoto Takao Shirai 《International journal of environmental analytical chemistry》2013,93(14):1057-1064
A biosensor for ammonia solution was developed with a flavin-containing monooxygenase-3 (FMO3). The biosensor consisted of a Clark-type dissolved oxygen electrode and an FMO3 immobilized membrane. In order to amplify the biosensor output, a substrate regeneration cycle obtained by coupling the monooxygenase with L-ascorbic acid (AsA) as the reducing reagent system, was applied. The AsA 10.0?mmol?L?1 concentration was able to optimally amplify the sensor output 11 times greater. The FMO3 biosensor was used with AsA to measure ammonia solution from 3.20 to 14.29?mmol?L?1 and from 0.09 to 21.7?mmol?L?1 with 5.0 and 10.0?mmol?L?1 AsA, respectively. The FMO biosensor also had a good reproducibility such as a 2.5% coefficient of variation in eight multiple measurements, and the output current was maintained over a few hours. The selectivity of the FMO biosensor being attributed to enzyme specificity was obtained for several chemical substances (trimethyl amine, methyl mercaptan, dimethyl sulphide, and so on). 相似文献
959.
S. Hashimoto H. Y. Sun A. Otsuki S. Kawakami F. Murata M. Yokomizo 《International journal of environmental analytical chemistry》2013,93(3-4):155-161
Abstract An enzymatic method was developed for the determination of ammonia concentrations in lake water. Lake water samples containing ammonia were mixed with a glutamate dehydrogenase (GIDH), reduced nicotinamide adenine dinucleotide phosphate (NADPH) and 2-oxoglutarate. The decrease in the absorbance intensity caused by the disappearance of NADPH by this reaction was measured at 340 nm. There was a linear relationship (r = 0.9997) between peak height and ammonia concentration over the range 0–29 μM. The detection limit was 0.29 μM for a sample volume of 250 μl. Interference of amino acids and urea at concentrations of 50 mg l?1 was negligible. Good agreement was found between the enzymatic method and indophenol blue colorimetry. 相似文献
960.
Michito Shiotsuka Takafumi Toda Kenta Matsubara Yuki Itou Takuto Hashimoto 《Transition Metal Chemistry》2013,38(8):913-922
A novel Pt(II) organometallic complex with 4-(4-ethynyl-phenylethynyl)-pyridine (DEBPy-H), namely [Pt(dppp)(DEBPy)2] (dppp = 1,3-bis-(diphenylphosphino)-propane), has been prepared by two synthetic routes. The DEBPy-H ligand was prepared by a shorter synthetic pathway and in higher yield than the method of previous reports. New Pt(II) organometallic complexes with DEBPy-H and four bidentate ligands [Pt(L–L)(DEBPy)2] (L–L = 1,2-bis-(diphenylphosphino)-benzene, bis-(dicyclohexyl)-ethane, 4,4′-dimethyl-2,2′-bipyridine, or 5,5′-dimethyl-2,2′-bipyridine) have also been prepared. These five Pt(II) complexes have two pyridyl units as an available coordination site that can operate as a metalloligand in nanoscale tectonics. A supramolecular complex of a tetranuclear metallocycle, [Pt(dppp)(DEBPy)2]2[Pt(dppp)]2(OTf)4, was synthesized from [Pt(dppp)(DEBPy)2] and [Pt(dppp)(OTf)2] as a corner connection through coordination-driven self-assembly. This supramolecular Pt(II) complex exists as a tetranuclear structure of the square type according to the interpretation of the ESI-mass and NMR spectra in solution. Five Pt(II) organometallics demonstrated the formation of similar tetranuclear metallocycles with [Pt(dppp)(OTf)2], as indicated by their ESI-mass and UV–vis spectra in solution. 相似文献