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211.
Ueno Katsuhiro Hatada Naoyuki Han Donglin Toyoura Kazuaki Uda Tetsuya 《Journal of Solid State Electrochemistry》2020,24(7):1523-1538
Journal of Solid State Electrochemistry - Y-doped BaZrO3 (BZY) is a promising candidate for electrolytes in protonic ceramic fuel cells. To achieve the high proton conductivities of sintered... 相似文献
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We propose a method for high-speed and highly accurate detection of the image difference by using the Fourier spectrum magnitude difference. The difference can be extracted from subtraction between the Fourier spectrum magnitude images of a standard image and a target image, which are multiplied by their Fourier spectrum phase images. The size effect against the detection result of difference was also investigated. 相似文献
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Masahiro ASAKA Katsuhiro MABE 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2014,90(7):251-258
In Japan, efforts have been directed toward improving the detection of early gastric cancer by double contrast radiography and endoscopy, since early cancer has a good prognosis, resulting in Japan having the world’s best diagnostic system for early gastric cancer. The 5-year survival rate of gastric cancer patients in Japan is much higher than in Western countries by the development of endoscopic treatment for early gastric cancer. In February 2013, Japanese national health insurance cover for H. pylori eradication therapy was expanded to patients with H. pylori-associated gastritis, a type of chronic gastritis. H. pylori-associated gastritis causes gastric and duodenal ulcers and gastric polyps, therefore, providing treatment for this gastritis is likely to substantially decrease the prevalence of both gastric and duodenal ulcer and gastric cancer. Patients with gastritis are tested for H. pylori infection and those who are positive receive eradication therapy followed by periodic endoscopic surveillance. If such an approach is pursued further in Japan, gastric cancer deaths will show a dramatic decline after 10–20 years. 相似文献
216.
Motosugi U Ichikawa T Oguri M Sano K Sou H Muhi A Matsuda M Fujii H Enomoto N Araki T 《Magnetic resonance imaging》2011,29(8):1047-1052
Objective
To compare the diagnostic ability of gadoxetic acid-enhanced hepatocyte-phase MR images with aspartate aminotransferase-to-platelet ratio index (APRI) to predict liver fibrosis stage.Materials and Methods
Our study included 100 patients who underwent gadoxetic acid-enhanced MRI and either liver biopsy or liver surgery. Liver fibrosis stage was histologically determined according to the METAVIR system: F0 (n=16), F1 (n=17), F2 (n=10), F3 (n=21) and F4 (n=36). Four measures were used as imaging-based fibrosis markers: liver-spleen contrast ratio, liver-enhancement ratio, corrected liver-enhancement ratio and spleen index. APRI represented a blood test-based fibrosis marker. The diagnostic ability of those fibrosis markers were compared through receiver-operating characteristic analysis.Results
The area under the curve (AUC) for APRI prediction of severe fibrosis (≥F3 and F4) was significantly greater than that of corrected liver-enhancement ratio. However, corrected liver-enhancement ratio had a greater AUC for prediction of mild fibrosis (≥F1) than APRI, although the difference was insignificant.Conclusion
Corrected liver-enhancement ratio with gadoxetic acid-enhanced MRI is correlated to the stage of liver fibrosis. APRI, however, has greater reliability for predicting severe fibrosis and cirrhosis than does the imaging-based fibrosis marker tested in this study. 相似文献217.
Poly(2-chloroethyl vinyl ether-alt-maleic anhydride) can exhibit lower critical solution temperature-type phase behavior reversibly by tuning the solvent composition
in mixed solvent of tetrahydrofuran (THF) and hexane. The effect of solvent composition and polymer concentration on cloud
point of polymer solution was investigated. The cloud point temperature for high molecular weight polymer was lower than that
for lower molecular weight polymer. High resolution 1H NMR spectra in mixed solvent of THF-d
8 and hexane were also measured for comprehending thermoresponsive behavior of polymer solution in molecular level; however,
any discontinuous change in the NMR signals around the cloud point could not be recognized. 相似文献
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Katsuhiro Maeda Kazuhide Morino Eiji Yashima 《Journal of polymer science. Part A, Polymer chemistry》2003,41(22):3625-3631
Cis–transoidal poly[(4-carboxyphenyl)acetylene] (poly- 1 ) complexed with optically active amines and amino alcohols showed an induced circular dichroism (ICD) in the ultraviolet–visible region because of a predominantly one-handed helix formation in water and in dimethyl sulfoxide (DMSO). The Cotton effect signs of the poly- 1 /chiral amino alcohol complexes were inverted in the presence of water, whereas the ICD pattern of the poly- 1 /chiral amine complexes showed no change, regardless of the water content. These results demonstrated that the helix sense of poly- 1 induced by optically active amino alcohols through noncovalent acid–base interactions could be switched by changes in the solvent ratio in the DMSO–water mixtures. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3625–3631, 2003 相似文献
220.
Recent progress in analytical terahertz (THz) spectroscopy is reviewed with illustrative examples showing that it is an effective method for detecting and identifying intermolecular interactions in chemical compounds, such as hydrogen bonds. The unique and characteristic properties of THz waves, their significance to both science and industry, and the bases of one of the successful fields of analytical THz spectroscopy, namely THz time-domain spectroscopy and THz imaging for chemical analysis, are described. Preliminary quantitative studies are presented to show the potential of THz spectroscopy for the detection and identification of intermolecular hydrogen bonds in unknown mixture samples. The selective detection of intramolecular hydrogen bonds and the detection of intramolecular interactions in ice are also introduced. Some brief remarks are provided on future developments, the main issues, and the prospects for analytical THz spectroscopy. 相似文献