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1.
Koji Kamagata Christina Andica Ayumi Kato Yuya Saito Wataru Uchida Taku Hatano Matthew Lukies Takashi Ogawa Haruka Takeshige-Amano Toshiaki Akashi Akifumi Hagiwara Shohei Fujita Shigeki Aoki 《International journal of molecular sciences》2021,22(10)
There has been an increasing prevalence of neurodegenerative diseases with the rapid increase in aging societies worldwide. Biomarkers that can be used to detect pathological changes before the development of severe neuronal loss and consequently facilitate early intervention with disease-modifying therapeutic modalities are therefore urgently needed. Diffusion magnetic resonance imaging (MRI) is a promising tool that can be used to infer microstructural characteristics of the brain, such as microstructural integrity and complexity, as well as axonal density, order, and myelination, through the utilization of water molecules that are diffused within the tissue, with displacement at the micron scale. Diffusion tensor imaging is the most commonly used diffusion MRI technique to assess the pathophysiology of neurodegenerative diseases. However, diffusion tensor imaging has several limitations, and new technologies, including neurite orientation dispersion and density imaging, diffusion kurtosis imaging, and free-water imaging, have been recently developed as approaches to overcome these constraints. This review provides an overview of these technologies and their potential as biomarkers for the early diagnosis and disease progression of major neurodegenerative diseases. 相似文献
2.
Control of the 1D self‐assembly pattern of colloidal quantum dots (QDs) on PbSO4 nanoribbon (NRb) templates is achieved. The internal structure of the NRbs is investigated by X‐ray diffraction, revealing the isotropic packing of the PbSO4 nanoclusters in the NRbs. Colloidal QDs in a chloroform/hexane mixture are adsorbed onto the region close to the edges of the NRbs and form a 1D assembly of straight single line or double lines by controlling the amount of OAm. This is the first demonstration of a densely packed 1D self‐assembly of colloidal QDs with a straight line pattern without the use of any molecular bridge or adhesive. Atomic force microscopy measurements of the NRbs show depressions in the phase profile along the width of the NRbs, corresponding to the position of the 1D QD chain. The amount of adsorbed QDs on the NRbs in solution decreases as the addition of OAm increases, suggesting that additional OAm prevents interaction between the QDs and NRbs but facilitates the uniform adsorption of the 1D assembly. The low‐dimensional self‐assembly of colloidal QDs in this study opens up the possibility for the creation of anisotropically assembled QD superstructures. 相似文献
3.
Toshihisa Miyazaki Syo Usami Ryo Inoue Yasuo Kogo Yutaro Arai 《Ceramics International》2019,45(7):9560-9566
Si-rich ytterbium silicide was fabricated by through an arc-melting technique for applying use as a bond coat material in an environmental barrier coating system. Evaluation of its potential was accomplished through oxidation tests in dry air and an inert atmosphere. The experimental results showed that the changes in weight and morphologies of ytterbium silicide observed after the tests depended on the oxygen partial pressure. Extensive oxidation and weight gain occurred after oxidation in air. In order to apply this material for hot structures, improvement of the oxidation resistance is needed. 相似文献
4.
Tomoko Okuyama Jun Shirakawa Kazuki Tajima Yoko Ino Heidrun Vethe Yu Togashi Mayu Kyohara Ryota Inoue Daisuke Miyashita Jinghe Li Nozomi Goto Taiga Ichikawa Shingo Yamasaki Haruka Ohnuma Rie Takayanagi Yayoi Kimura Hisashi Hirano Yasuo Terauchi 《International journal of molecular sciences》2020,21(21)
5.
Toshiaki Kikuma Tadao Ishikawa Masahiro Takasaki Hiroshi Mochikawa Atsuhiko Kuzumaki Kazuya Kodani Takeru Murao 《Electrical Engineering in Japan》2015,192(3):54-64
The recent years have seen an increasing trend in the cumulative installed capacity of distributed generators. As a result, voltage management may become difficult in existing power distribution systems in the future. A STATCOM (STAtic synchronous COMpensator) is a promising option for solving this problem because it can control reactive power rapidly and continuously. For a distribution system, STATCOM needs to be pole‐mounted to realize its low cost. However, a transformer for a STATCOM is large and heavy, and hence it is difficult to install a STATCOM on a distribution pole. We adopt a transformerless STATCOM to reduce STATCOM size and use SiC devices with low‐loss performance to obtain a more compact and efficient STATCOM. There are a large number of circuits available for a STATCOM, and there has been considerable research on performance comparisons among these circuits. However, these comparisons were drawn under different conditions, including switching frequency and level number for the circuits. In addition, these comparisons do not include the use of SiC devices. We made an equitable comparison for a 100 kVa pole‐mounted STATCOM using SiC devices. We discuss the performance and characteristics of each circuit in terms of efficiency and volume. 相似文献
6.
Belo Lourenço Cláudio Cousineau Denis Faissole Florian Marché Claude Mentré David Inoue Hiroaki 《International Journal on Software Tools for Technology Transfer (STTT)》2022,24(6):977-997
International Journal on Software Tools for Technology Transfer - Programmable Logic Controllers are industrial digital computers used as automation controllers in manufacturing processes. The... 相似文献
7.
Tomoyo Okumura Kenya Sonobe Asami Ohashi Harumi Watanabe Katsushi Watanabe Hiroshi Oyamada Masaaki Aramaki Toshiaki Ougizawa 《Polymer Engineering and Science》2020,60(7):1699-1711
Simultaneous one-pot syntheses of PA66 and HAp were carried out by extracting H2O and CO2 from PA66 monomers and HAp raw materials, respectively, resulting in the formation of a polyamide (PA) 66-hydroxyapatite (HAp) nanocomposite. During the process, a spherical nano-sized HAp particle was precipitated following dissolution of micro-sized CaHPO4・2H2O. The PA66 monomers were subsequently adsorbed onto the generated HAp product. Some of the adsorbed PA66 monomers formed a bound polymer on HAp, and an increase in the adhesiveness of the PA66-HAp interface was observed as the polymerization progressed. During this process, the synthesis of a nanocomposite from a micro-sized raw material and creation of an autonomous strong interface between the matrix and filler was achieved. In addition, the shape of the resultant HAp was controllable and could be modified to needle shape by the addition of F− and Mg2+ ions to the raw material. HAp could also be changed to plate shape via octa-calcium phosphate (OCP). Notably, during the synthesis, the filler shape of the nanocomposite could be controlled to 0D (particle), 1D (needle), and 2D (plate). 相似文献
8.
Sakama Chiaki Inoue Katsumi Sato Taisuke 《Annals of Mathematics and Artificial Intelligence》2021,89(12):1133-1153
Annals of Mathematics and Artificial Intelligence - This paper introduces a novel approach to computing logic programming semantics. First, a propositional Herbrand base is represented in a vector... 相似文献
9.
This paper describes the extent of railway reform in a selection of representative transition economies and discusses some of the factors that will influence the success of the reforms in the future. Railways in the European Union’s area of influence, such as those in Poland and Romania, which are financially weak and losing market share to road transport, have advanced on the railway reform path more than those in Kazakhstan, Russia and Ukraine. The latter are financially strong and enjoy a dominant share of the freight market. Railway reform agendas are ambitious on paper but suffer from implementation delays. The combination of favourable financial conditions, weak inter-modal competition, and politicised decision-making slows down reform. The success of railway reform depends not only on building institutional capacity to make the railways market-oriented and adequately regulated, but also on promoting wider reforms in the economy, such as enterprise restructuring and financial sector development. 相似文献
10.
J B Qu C Jin Y T Liu S N Yin T Watanabe H Nakatsuka K Seiji O Inoue M Ikeda 《The Science of the total environment》1988,77(1):35-44
Blood samples were obtained from 537 adults (age greater than or equal to 16 years) living in three cities in China; in Hefei in 1985, and in Shenyang and Jinxi in 1987. The samples were subjected to blood lead (Pb-B) analyses. The subjects were factory workers either in solvent-synthesizing or solvent application plants with no known exposure to metals (including lead). Their smoking and drinking habits were confirmed in medical interviews. Blood lead was significantly higher in smokers than in non-smokers, although no dose-dependency was observed. The Pb-B values in non-smokers were log-normally distributed. The Pb-B among non-smokers was significantly higher in men [104.0 micrograms l-1 (1.428) 87] [geometric mean (geometric standard deviation) number of determinations] than in women [75.5 micrograms l-1 (1.358) 225] when the data from the three cities were combined. There was a significant difference in the Pb-B levels of non-smoking men in the three cities studied, suggesting that regional food habits should be considered as a possible contributory factor of a non-occupational nature. The present findings are compared with observations from Korea and Japan from the viewpoint of environmental health. 相似文献