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181.
Yasuo Iida Muthupandian Ashokkumar Toru Tuziuti Teruyuki Kozuka Kyuichi Yasui Atsuya Towata Judy Lee 《Ultrasonics sonochemistry》2010,17(2):473-479
To characterize the bubble populations (size and its number distribution) in a sonochemical reactor, a simple but powerful technique based on the Fraunhofer laser diffraction (LD) has been proposed. In this method, the acoustic wave disturbance to the laser probe in the sonochemical reaction field was eliminated by the temporal separation using pulsed sonication (pulsed LD). With this relatively simple strategy, the temporal development of the bubble size distribution could be evaluated by pulsed LD. A number density of bubbles was estimated by using a calibration data obtained with monosized standard particles. In addition, the effect of pulse length and a surfactant on the bubble population phenomena in a multibubble system are discussed. 相似文献
182.
Takeshi Yasui Kunihiko Sasaki Yoshiyuki Tohno Tsutomu Araki 《Optical and Quantum Electronics》2005,37(13-15):1397-1408
We propose a nonlinear optical probe method to image the distribution of collagen fiber orientation in human tissue by measuring the polarization of collagen-induced second-harmonic-generation (SHG) light (SHG polarimetry). Depth-resolved SHG polarimetry, with a depth resolution of 14 μm, was used to evaluate the cross-sectional profile of collagen fiber orientation in Achilles tendon and dentin, revealing a characteristic distribution of collagen orientation along the depth direction. We evaluated the two-dimensional (2D) lateral distribution of collagen fiber orientation in back reticular dermis and anklebone by polarization-resolved SHG imaging, and confirmed an appreciable difference in the distribution profiles of the two samples. We further extended the method to a depth-resolved measurement of the three-dimensional (3D) distribution of collagen orientation in anklebone. The proposed system promises to be a powerful tool for in vivo measurement of collagen fiber orientation in human tissue. 相似文献
183.
Using 1-octanol/octane mixed solvents, the extraction of aluminum(III), gallium(III) and indium(III) with 8-quinolinol was carried out at 25 degrees C. The formation constants of the respective metal(III) 8-quinolinolates in the aqueous phase and their partition constants between the mixed solvents and water were determined based on an analysis of the extraction equilibria. The relationship between the partition constants of 8-quinolinol and its complexes was analyzed by the regular solution theory. The molar volumes of aluminum(III), gallium(III) and indium(III) 8-quinolinolates, calculated from the present results, suggest that the electrostriction effect functions in complex forming. It has been found that octane/1-octanol mixed solvents were available not only for the extraction of metal ions, but also for determining the formation constants of these metal 8-quinolinolates in the aqueous phase and their partition constants. 相似文献
184.
Aline Barbosa Macedo Daniela Sayuri Mizobuti Tulio de Almeida Hermes Rafael Dias Mâncio Adriana Pertille Larissa Akemi Kido Valéria Helena Alves Cagnon Elaine Minatel 《Photochemistry and photobiology》2020,96(1):200-207
This study analyzed photobiomodulation therapy (PBMT) effects on regenerative, antioxidative, anti-inflammatory and angiogenic markers in the dystrophic skeletal muscle of mdx mice, the experimental model of Duchenne muscular dystrophy (DMD), during the acute phase of dystrophy disease. The following groups were set up: Ctrl (control group of normal wild-type mice; C57BL/10); mdx (untreated mdx mice); mdxPred (mdx mice treated with prednisolone) and mdxLA (mdx mice treated with PBMT). The PBMT was carried out using an Aluminum Gallium Arsenide (AIGaAs; IBRAMED® laserpulse) diode, 830 nm wavelength, applied on the dystrophic quadriceps muscle. The mdxLA group showed a degenerative and regenerative area reduction simultaneously with a MyoD level increase, ROS production and inflammatory marker reduction and up-regulation in the VEGF factor. In addition, PBMT presented similar effects to prednisolone treatment in most of the parameters analyzed. In conclusion, our results indicate that PBMT in the parameters selected attenuated the dystrophic phenotype of mdx mice, improving skeletal muscle regeneration; reducing the oxidative stress and inflammatory process; and up-regulating the angiogenic marker. 相似文献
185.
Dr. Dušan Kojić Prof. Dr. Roumiana Tsenkova Katsufumi Tomobe Prof. Dr. Kenji Yasuoka Prof. Dr. Masato Yasui 《Chemphyschem》2014,15(18):4077-4086
Interionic distances are shorter in concentrated ionic solutions, thus instigating the interaction and overlap of hydration shells, as ions become separated by only one or two layers of water molecules. The simultaneous interaction of water with two oppositely charged ions has, so far, only been investigated by computer simulation studies, because the isolated vibrational spectroscopic signature of these molecules remains undetected. Our combined near‐infrared spectroscopic and molecular dynamics simulation studies of alkali halide solutions present a distinct spectral feature, which is highly responsive to depletion of bulk water and merging of hydration shells. The analysis of this spectral feature demonstrates that absorption trends are in good agreement with the law of matching affinities, thus providing the first successful vibrational spectroscopic treatment of this topic. Combined with commonly observed near‐infrared bands, this feature provides a spectral pattern that describes some relevant aspects of ionic hydration. 相似文献
186.
Motozumi Ando Masaki Hirabatake Hisateru Yasui Shoji Fukushima Nobuyuki Sugioka Tohru Hashida 《Biomedical chromatography : BMC》2020,34(3):e4776
Mitotane is a key drug for the treatment of adrenal cortical carcinoma. Due to its narrow therapeutic window, 14–20 μg/mL, monitoring its concentration is crucially important. In this study, a simplified method for measuring mitotane in plasma using gas chromatography-electron ionization-mass spectrometry (GC-EI-MS) was developed. Through deproteination and liquid–liquid extraction, mitotane and an internal standard (IS) were extracted from plasma samples. GC-EI-MS yielded retention times of 8.2 and 8.7 min, for mitotane and the IS, respectively, with a total run time of 12 min. Selectivity and intra-/inter-batch accuracy and precision analyses provided a lower limit of quantification of 0.25 μg/mL, and a calibration curve between 0.25 and 40 μg/mL had good linearity (coefficient of determination = 0.992). The matrix effect factor and percent recovery of the method had good precision. Additionally, long-term sample stability was observed below 4°C. In a clinical setting, mitotane levels in plasma from an adrenal cortical carcinoma patient were within calibration range. Therefore, this simplified method can be applied to routine therapeutic drug monitoring of mitotane, which may contribute to improved treatment of adrenal cortical carcinoma. 相似文献
187.
Anja C. Andersen Harald Mutschke Thomas Posch Michiel Min Akemi Tamanai 《Journal of Quantitative Spectroscopy & Radiative Transfer》2006,100(1-3):4-15
Particle shape and aggregation have a strong influence on the spectral profiles of infrared phonon bands of solid dust grains. Calculating these effects is difficult due to the often extreme refractive index values in these bands. In this paper, we use the discrete dipole approximation (DDA) and the T-matrix method to compute the absorption band profiles for simple clusters of touching spherical grains. We invest reasonable amounts of computation time in order to reach high dipole grid resolutions and take high multipolar orders into account, respectively. The infrared phonon bands of three different refractory materials of astrophysical relevance are considered—silicon carbide, wustite and silicon dioxide. We demonstrate that even though these materials display a range of material properties and therefore different strengths of the surface resonances, a complete convergence is obtained with none of the approaches. For the DDA, we find a strong dependence of the calculated band profiles on the exact dipole distribution within the aggregates, especially in the vicinity of the contact points between their spherical constituents. By applying a recently developed method to separate the material optical constants from the geometrical parameters in the DDA approach, we are able to demonstrate that the most critical material properties are those where the real part of the refractive index is much smaller than unity. 相似文献
188.
Takashi Yasui Nozomu Komatsu Kazuki Egami Hiromichi Yamada Akio Yuchi 《Analytical sciences》2007,23(8):1011-1014
Bidentate and tridentate heterocyclic azo compounds with and without a long alkyl chain were prepared and examined for cation exchange chromatography of manganese, zinc, and cadmium; these ions could not be separated by reversed phase HPLC following precolumn derivatization with heterocyclic azo compounds owing to the dissociation of the complexes. The newly prepared azo compounds having a long alkyl chain favorably orientate in the reversed-phase stationary phase such that the coordinating parts of the ligand may make contact with metal ions in the mobile phase. Bidentate ligands showed sharp peaks but almost no resolution of manganese and cadmium. A tridentate ligand strongly retained all the three metal ions, which could be separated within 10 min by a competing ligand and by optimizing the pH. 相似文献
189.
Yusuke Nakashima Kazunori Hirabayashi Masanori Yasui Fujiko Iwasaki 《Tetrahedron letters》2004,45(11):2301-2303
An optically pure seleninic acid was isolated as stable crystals for the first time by chiral crystallization. The relationship between the absolute configurations and the circular dichroism spectra of the enantiomers could be determined by X-ray crystallographic analysis. 相似文献
190.
The reversed-phase high-performance liquid chromatography of 8-quinolinethiol (Hqt) complexes of Fe, Co, Ni, Cu, Zn, Hg and Pb on an octadecyl-bonded silica gel stationary phase was examined. The Pb complex dissociated in the column. The retention and separation of other complexes depended on the composition of the mobile phase. EDTA as an additive displaced the Zn complex and eliminated its peak. All the other metal complexes and also Hqt and its disulphide were separated in 23 min by using methanol-water (82:18, v/v) as the mobile phase. The complexes formed by the reaction of Co(II) and Hqt gave three peaks, which were assigned as fac(S)-CoIII(qt)3, mer(S)-CoIII(qt)3 and CoII(qt)2, respectively. This method is applicable to the simultaneous determination of Fe, Co, Ni, Cu and Hg. 相似文献