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161.
162.
A lignan skeleton is prepared in good yield through desulfurization of 3,4-dibenzyl-thiophene or 2,5-diaryl-3,4-dimethylthiophenes which are obtained by the nickel- or palladium-phosphine complex catalyzed Grignard cross-coupling reaction of halothiophenes. 相似文献
163.
164.
Akio Yamada 《Probability Theory and Related Fields》1970,15(3):230-238
Summary Hunt's theory of potentials has recently been treated from the operator-theoretical viewpoint by K. Yosida in a series of his papers. The aim of the treatment is to analyze the mechanism of Hunt's theory and moreover to contribute new and sharpened results to the theory. In the present paper we shall develop his work into showing that the closure of what has been called so far potential operator with its domain restricted to the space of continuous functions with compact supports does deserve the title of the potential operator by verifying its various properties. There will also be given generalizations and straightforward proofs of the theorems proved by K. Yosida concerning pseudoresolvents and the principle of majoration. It will enable us in the near future to treat the whole theory not only in the function spaces such as c
(S), but also in the abstract Banach lattices. 相似文献
165.
166.
Yasunari Hashimoto Junichi Ushiba Akio Kimura Meigen Liu Yutaka Tomita 《BMC neuroscience》2010,11(1):117
Background
For severely paralyzed people, a brain-computer interface (BCI) provides a way of re-establishing communication. Although subjects with muscular dystrophy (MD) appear to be potential BCI users, the actual long-term effects of BCI use on brain activities in MD subjects have yet to be clarified. To investigate these effects, we followed BCI use by a chronic tetraplegic subject with MD over 5 months. The topographic changes in an electroencephalogram (EEG) after long-term use of the virtual reality (VR)-based BCI were also assessed. Our originally developed BCI system was used to classify an EEG recorded over the sensorimotor cortex in real time and estimate the user's motor intention (MI) in 3 different limb movements: feet, left hand, and right hand. An avatar in the internet-based VR was controlled in accordance with the results of the EEG classification by the BCI. The subject was trained to control his avatar via the BCI by strolling in the VR for 1 hour a day and then continued the same training twice a month at his home. 相似文献167.
168.
We consider the Penrose–Fife phase field model [Thermodynamically consistent models of phase-field type for the kinetics of phase transitions, Physica D 43 (1990) 44–62] with homogeneous Neumann boundary condition to the nonlinear heat flux q=∇(1/θ), i.e., q=0 on the boundary, where θ>0 is the temperature. There is a unique H1 solution globally in time with the non-empty, connected, compact ω-limit set composed of stationary solutions, and the linearized stable stationary solution is dynamically stable. 相似文献
169.
Kenji Asano Akio Miyao Hirohiko Hirochika Hidemi Kitano Makoto Matsuoka Motoyuki Ashikari 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2010,86(3):265-273
Plant height is one of the most important traits in crop improvement. Therefore revealing the mechanism of plant elongation and controlling plant height in accordance with breeding object is important. In this study we analyzed a novel dwarf mutant, ssd1, of which phenotype is different from typical GA- or BR-related dwarf phenotype. ssd1 exhibits pleiotropic defects in elongation of various organs such as stems, roots, leaves, and flowers. ssd1 also shows abnormal cell files and shapes, which suggests defects of normal cell division in the mutant. Map-based cloning and complementation test demonstrated that the dwarf phenotype in ssd1 mutant was caused by insertion of retrotransposon in a gene, which encodes plant-specific protein with unknown biochemical function. A BLAST search revealed that SSD1-like genes exist in diverse plant species, including monocots and dicots, but not fern and moss. Our results demonstrate that SSD1 controls plant elongation by controlling cell division in higher plants. 相似文献
170.
Tetsuo Tsuchiya Akio Watanabe Tomohiko Nakajima Toshiya Kumagai 《Applied Physics A: Materials Science & Processing》2010,101(4):681-684
Europium-doped yttrium oxide (Y2O3:Eu) thin films were successfully deposited on quartz and ITO/glass substrates by excimer-laser-assisted metal organic deposition
(ELAMOD) at low temperatures. The effects of laser wavelength and thermal temperature on the films’ crystallinity and photoluminescence
properties were investigated. Films irradiated by an ArF laser at 80 mJ/cm2 and 400–500°C were highly crystallized compared with those prepared by thermal MOD. In contrast, when the film was irradiated
by a KrF laser at 500°C, no crystalline Y2O3:Eu was formed. The Y2O3:Eu film irradiated by the ArF laser at 80 mJ/cm2 and 500°C showed typical PL spectra of Eu3+ ions with cubic symmetry and a 5D0→7F2 transition at ∼612 nm. The PL intensity at 612 nm was much higher for the film prepared with ELAMOD than for that prepared
by the thermal-assisted process, and the photoemission intensity of the film prepared with ELAMOD strongly depended on the
substrate material. 相似文献