1
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Lee J, Park E, Fujisawa A, Lee H. Diatom Silica/Polysaccharide Elastomeric Hydrogels: Adhesion and Interlocking Synergy. ACS Appl Mater Interfaces 2021; 13:21703-21713. [PMID: 33938215 DOI: 10.1021/acsami.1c01279] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The addition of particles during the sol-to-gel conversion process generally enhances the mechanical properties of the resulting hydrogels. However, the impact of the addition of porous particles during such a process remains an open question. Herein, we report hydrogel-to-elastomer conversions by natural porous particles called diatom frustule silica, namely, Melosira nummuloides. The surface pores provide mechanical interlocking points for polymers that are reinforced by gelation. The most critical aspect when choosing polymeric materials is the presence of water-resistant adhesion moieties, such as catechol, along a polymer chain, such as chitosan. Without catechol, no sol-to-gel conversion is observed; thus, no elastomeric hydrogel is produced. The resulting hybrid gel reveals reversible compressibility up to a 60% strain and high stretchability even up to ∼400% in area. Further, in vivo study demonstrates that the hybrid composite gel can be used as a therapeutic for pressure-induced ulcers. The synergy of chemical adhesion and physical chain entanglement via pores provides a way to fabricate a new class of 100% water-based elastomeric materials.
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Affiliation(s)
- Jeehee Lee
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Eunsook Park
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Aki Fujisawa
- Tokyo Institute of Technology, 2 Chome-12-1 Ookayama, Meguro City, Tokyo 152-8550, Japan
| | - Haeshin Lee
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
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2
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Ido T, Fujisawa A, Takemura K, Kobayashi TK, Nishimura D, Kasuya N, Fukuyama A, Moon C, Yamasaki K, Inagaki S, Nagashima Y, Yamada T. Conceptual design of heavy ion beam probes on the PLATO tokamak. Rev Sci Instrum 2021; 92:053553. [PMID: 34243249 DOI: 10.1063/5.0041814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2020] [Accepted: 05/05/2021] [Indexed: 06/13/2023]
Abstract
Heavy ion beam probe (HIBP) systems have been designed for the new tokamak, PLATO [A. Fujisawa, AIP Conf. Proc. 1993, 020011 (2018)]. The designs have been completed, and the installations are in progress. Two HIBPs are being installed in toroidal sections 180° apart to investigate long-range correlations in the toroidal direction. Each HIBP consists of an injection beamline and a detection beamline as usual. Yet, one of the HIBPs is equipped with an additional detection beamline; the measurement positions of its two detection beamlines can be placed on almost the same magnetic surface yet at poloidal angles that differ by ∼180°. The use of three detection beamlines allows us to investigate spatial asymmetry and long-range correlations in both the toroidal and poloidal directions, simultaneously. The detected beam intensity is expected to be enough for turbulence measurements in almost the entire plasma region when the electron density is up to 1 × 1019 m-3 by selecting appropriate ion species for the probe beam. Each detector has three channels 10 mm apart, allowing measurement of local structures of micro-scale turbulence. Therefore, using the HIBPs on the PLATO tokamak will enable both local and global properties of plasma turbulence to be investigated, simultaneously.
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Affiliation(s)
- T Ido
- Research Institute for Applied Mechanics, Kyushu University, 6-1 Kasugakoen, Kasuga, Fukuoka 816-8580, Japan
| | - A Fujisawa
- Research Institute for Applied Mechanics, Kyushu University, 6-1 Kasugakoen, Kasuga, Fukuoka 816-8580, Japan
| | - K Takemura
- Department of Applied Energy, Nagoya University, Furocho, Chikusa, Nagoya 464-8603, Japan
| | - T-K Kobayashi
- Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, 6-1 Kasugakoen, Kasuga, Fukuoka 816-8580, Japan
| | - D Nishimura
- Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, 6-1 Kasugakoen, Kasuga, Fukuoka 816-8580, Japan
| | - N Kasuya
- Research Institute for Applied Mechanics, Kyushu University, 6-1 Kasugakoen, Kasuga, Fukuoka 816-8580, Japan
| | - A Fukuyama
- Department of Nuclear Engineering, Kyoto University, Nisikyo-ku, Kyoto 615-8540, Japan
| | - C Moon
- Research Institute for Applied Mechanics, Kyushu University, 6-1 Kasugakoen, Kasuga, Fukuoka 816-8580, Japan
| | - K Yamasaki
- Research Institute for Applied Mechanics, Kyushu University, 6-1 Kasugakoen, Kasuga, Fukuoka 816-8580, Japan
| | - S Inagaki
- Research Institute for Applied Mechanics, Kyushu University, 6-1 Kasugakoen, Kasuga, Fukuoka 816-8580, Japan
| | - Y Nagashima
- Research Institute for Applied Mechanics, Kyushu University, 6-1 Kasugakoen, Kasuga, Fukuoka 816-8580, Japan
| | - T Yamada
- Faculty of Arts and Science, Kyushu University, 6-1 Kasugakoen, Kasuga, Fukuoka 816-8580, Japan
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3
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Yamasaki K, Fujisawa A, Nagashima Y, Moon C, Inagaki S, Yamada T. Tomography system for two-dimensional observation of fluctuation in magnetized plasma. Rev Sci Instrum 2020; 91:033502. [PMID: 32259999 DOI: 10.1063/1.5144480] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Accepted: 02/28/2020] [Indexed: 06/11/2023]
Abstract
A tomography system is developed for observing local fluctuations, pursuing higher spatial resolution, over the entire plasma of a linear cylindrical plasma. The system is equipped with totally 126 lines-of-sight that are distributed equally to six sets of light guide arrays placed around the plasma. The system has succeeded in measuring the two-dimensional structure of plasma emission and resolving coherent fluctuation structures, with spatial resolution comparable to the ion Larmor radius.
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Affiliation(s)
- K Yamasaki
- Research Institute for Applied Mechanics, Kyushu University, Kasuga 816-8580, Japan
| | - A Fujisawa
- Research Institute for Applied Mechanics, Kyushu University, Kasuga 816-8580, Japan
| | - Y Nagashima
- Research Institute for Applied Mechanics, Kyushu University, Kasuga 816-8580, Japan
| | - C Moon
- Research Institute for Applied Mechanics, Kyushu University, Kasuga 816-8580, Japan
| | - S Inagaki
- Research Institute for Applied Mechanics, Kyushu University, Kasuga 816-8580, Japan
| | - T Yamada
- Faculty of Arts and Science, Kyushu University, Fukuoka 819-0395, Japan
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4
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Shimizu A, Fujisawa A, Ohshima S, Nakano H, Minami T, Isobe M, Okamura S, Matsuoka K. Density profile measurement with a heavy ion beam probe in a toroidal plasma of the compact helical system. Rev Sci Instrum 2018; 89:113507. [PMID: 30501308 DOI: 10.1063/1.5039571] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 10/19/2018] [Indexed: 06/09/2023]
Abstract
A possibility of electron density measurements with heavy ion beam probes (HIBPs) has been demonstrated, along with their capability to measure the potential and magnetic field. A method has been proposed to reconstruct the electron density profile [A. Fujisawa et al., Rev. Sci. Instrum. 74, 3335 (2003)]. In the method, the profile of secondary beam currents is converted into a local density profile by taking into account local brightness and so-called path integral effects which mean the effect of beam attenuation along the beam orbit. Here the article presents the HIBP measurement of the electron density profile after the proposed method was first applied on the real experimental data of compact helical system plasmas. In the real application, the hollow density and the peaked profiles are successfully obtained with sufficiently high temporal resolution (a few ms), in accordance with the electron density profile measured with Thomson scattering for electron cyclotron resonance heating and neutral beam injection plasmas.
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Affiliation(s)
- A Shimizu
- National Institute for Fusion Science, Oroshi, Toki, Gifu 509-5292, Japan
| | - A Fujisawa
- Research Institute for Applied Mechanics, Kyushu University, 6-1 Kasuga-Kohen, Kasuga 816-8580, Japan
| | - S Ohshima
- Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
| | - H Nakano
- National Institute for Fusion Science, Oroshi, Toki, Gifu 509-5292, Japan
| | - T Minami
- Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
| | - M Isobe
- National Institute for Fusion Science, Oroshi, Toki, Gifu 509-5292, Japan
| | - S Okamura
- National Institute for Fusion Science, Oroshi, Toki, Gifu 509-5292, Japan
| | - K Matsuoka
- National Institute for Fusion Science, Oroshi, Toki, Gifu 509-5292, Japan
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5
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Kobayashi T, Sasaki M, Ido T, Kamiya K, Miura Y, Nagashima Y, Ida K, Inagaki S, Fujisawa A, Itoh SI, Itoh K. Quantification of Turbulent Driving Forces for the Geodesic Acoustic Mode in the JFT-2M Tokamak. Phys Rev Lett 2018; 120:045002. [PMID: 29437414 DOI: 10.1103/physrevlett.120.045002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Revised: 11/29/2017] [Indexed: 06/08/2023]
Abstract
We investigate spatial structures of turbulence and turbulent transport modulated by the geodesic acoustic mode (GAM), from which the excitation mechanism of the GAM is discussed. The GAM is found to be predominantly excited through a localized Reynolds stress force, rather than the dynamic shearing force. The evaluated growth rate is larger than the linear damping coefficients and is on the same order of magnitude as the effective growth rate evaluated from time evolution in the GAM kinetic energy.
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Affiliation(s)
- T Kobayashi
- National Institute for Fusion Science, National Institutes of Natural Sciences, Toki 509-5292, Japan
| | - M Sasaki
- Research Institute for Applied Mechanics, Kyushu University, Kasuga 816-8580, Japan
- Research Center for Plasma Turbulence, Kyushu University, Kasuga 816-8580, Japan
| | - T Ido
- National Institute for Fusion Science, National Institutes of Natural Sciences, Toki 509-5292, Japan
| | - K Kamiya
- National Institutes for Quantum and Radiological Science and Technology, Naka 311-0193, Japan
| | - Y Miura
- Japan Atomic Energy Agency, Naka 311-0193, Japan
| | - Y Nagashima
- Research Institute for Applied Mechanics, Kyushu University, Kasuga 816-8580, Japan
- Research Center for Plasma Turbulence, Kyushu University, Kasuga 816-8580, Japan
| | - K Ida
- National Institute for Fusion Science, National Institutes of Natural Sciences, Toki 509-5292, Japan
- Research Center for Plasma Turbulence, Kyushu University, Kasuga 816-8580, Japan
| | - S Inagaki
- Research Institute for Applied Mechanics, Kyushu University, Kasuga 816-8580, Japan
- Research Center for Plasma Turbulence, Kyushu University, Kasuga 816-8580, Japan
| | - A Fujisawa
- Research Institute for Applied Mechanics, Kyushu University, Kasuga 816-8580, Japan
- Research Center for Plasma Turbulence, Kyushu University, Kasuga 816-8580, Japan
| | - S-I Itoh
- Research Institute for Applied Mechanics, Kyushu University, Kasuga 816-8580, Japan
- Research Center for Plasma Turbulence, Kyushu University, Kasuga 816-8580, Japan
| | - K Itoh
- National Institute for Fusion Science, National Institutes of Natural Sciences, Toki 509-5292, Japan
- Research Center for Plasma Turbulence, Kyushu University, Kasuga 816-8580, Japan
- Institute of Science and Technology Research, Chubu University, Kasugai 487-8501, Japan
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6
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Kobayashi T, Itoh K, Ido T, Kamiya K, Itoh SI, Miura Y, Nagashima Y, Fujisawa A, Inagaki S, Ida K. Turbulent transport reduction induced by transition on radial electric field shear and curvature through amplitude and cross-phase in torus plasma. Sci Rep 2017; 7:14971. [PMID: 29097702 PMCID: PMC5668279 DOI: 10.1038/s41598-017-14821-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Accepted: 10/16/2017] [Indexed: 11/23/2022] Open
Abstract
Spatiotemporal evolutions of radial electric field and turbulence are measured simultaneously in the H-mode transition, which is a prototypical example of turbulence structure formation in high-temperature plasmas. In the dynamical phase where transport barrier is established abruptly, the time-space-frequency-resolved turbulent particle flux is obtained. Here we report the validation of the mechanism of transport barrier formation quantitatively. It is found that the particle flux is suppressed predominantly by reducing density fluctuation amplitude and cross phase between density fluctuation and potential fluctuation. Both radial electric field shear and curvature are responsible for the amplitude suppression as was predicted by theory. Turbulence amplitude reduction immediately responds to the growth of the radial electric field non-uniformity and saturates, while cross phase continuously approaches zero.
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Affiliation(s)
- T Kobayashi
- National Institute for Fusion Science, National Institutes of Natural Sciences, Toki, 509-5292, Japan.
| | - K Itoh
- National Institute for Fusion Science, National Institutes of Natural Sciences, Toki, 509-5292, Japan.,Institute of Science and Technology Research, Chubu University, Kasugai, 487-8501, Japan.,Research Center for Plasma Turbulence, Kyushu University, Kasuga, 816-8580, Japan
| | - T Ido
- National Institute for Fusion Science, National Institutes of Natural Sciences, Toki, 509-5292, Japan
| | - K Kamiya
- National Institute for Quantum and Radiological Science and Technology, Naka, 311-0193, Japan
| | - S-I Itoh
- Research Center for Plasma Turbulence, Kyushu University, Kasuga, 816-8580, Japan.,Research Institute for Applied Mechanics, Kyushu University, Kasuga, 816-8580, Japan
| | - Y Miura
- Japan Atomic Energy Agency, Tokai, 319-1184, Japan
| | - Y Nagashima
- Research Center for Plasma Turbulence, Kyushu University, Kasuga, 816-8580, Japan.,Research Institute for Applied Mechanics, Kyushu University, Kasuga, 816-8580, Japan
| | - A Fujisawa
- Research Center for Plasma Turbulence, Kyushu University, Kasuga, 816-8580, Japan.,Research Institute for Applied Mechanics, Kyushu University, Kasuga, 816-8580, Japan
| | - S Inagaki
- Research Center for Plasma Turbulence, Kyushu University, Kasuga, 816-8580, Japan.,Research Institute for Applied Mechanics, Kyushu University, Kasuga, 816-8580, Japan
| | - K Ida
- National Institute for Fusion Science, National Institutes of Natural Sciences, Toki, 509-5292, Japan.,Research Center for Plasma Turbulence, Kyushu University, Kasuga, 816-8580, Japan
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7
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Nakamura K, Alam M, Jiang Y, Mitarai O, Kurihara K, Kawamata Y, Sueoka M, Takechi M, Hasegawa M, Tokunaga K, Araki K, Zushi H, Hanada K, Fujisawa A, Idei H, Nagashima Y, Kawasaki S, Nakashima H, Higashijima A, Nagata T, Fukuyama A. Plasma equilibrium based on RF-driven current profile without assuming nested magnetic surfaces on QUEST. Fusion Engineering and Design 2017. [DOI: 10.1016/j.fusengdes.2017.05.070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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8
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Wang Z, Hanada K, Yoshida N, Shimoji T, Miyamoto M, Oya Y, Zushi H, Idei H, Nakamura K, Fujisawa A, Nagashima Y, Hasegawa M, Kawasaki S, Higashijima A, Nakashima H, Nagata T, Kawaguchi A, Fujiwara T, Araki K, Mitarai O, Fukuyama A, Takase Y, Matsumoto K. Measurement of thickness of film deposited on the plasma-facing wall in the QUEST tokamak by colorimetry. Rev Sci Instrum 2017; 88:093502. [PMID: 28964174 DOI: 10.1063/1.5000739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 08/17/2017] [Indexed: 06/07/2023]
Abstract
After several experimental campaigns in the Kyushu University Experiment with Steady-state Spherical Tokamak (QUEST), the originally stainless steel plasma-facing wall (PFW) becomes completely covered with a deposited film composed of mixture materials, such as iron, chromium, carbon, and tungsten. In this work, an innovative colorimetry-based method was developed to measure the thickness of the deposited film on the actual QUEST wall. Because the optical constants of the deposited film on the PFW were position-dependent and the extinction coefficient k1 was about 1.0-2.0, which made the probing light not penetrate through some thick deposited films, the colorimetry method developed can only provide a rough value range of thickness of the metal-containing film deposited on the actual PFW in QUEST. However, the use of colorimetry is of great benefit to large-area inspections and to radioactive materials in future fusion devices that will be strictly prohibited from being taken out of the limited area.
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Affiliation(s)
- Z Wang
- Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - K Hanada
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - N Yoshida
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - T Shimoji
- Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - M Miyamoto
- Department of Material Science, Shimane University, Matsue, Shimane 690-8504, Japan
| | - Y Oya
- Faculty of Science, Shizuoka University, Ohya, Shizuoaka 422-8529, Japan
| | - H Zushi
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - H Idei
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - K Nakamura
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - A Fujisawa
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - Y Nagashima
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - M Hasegawa
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - S Kawasaki
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - A Higashijima
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - H Nakashima
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - T Nagata
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - A Kawaguchi
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - T Fujiwara
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - K Araki
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - O Mitarai
- Institute of Industrial Science and Technology Research, Tokai University, Kumamoto 862-8652, Japan
| | - A Fukuyama
- Department of Nuclear Engineering, Kyoto University, Kyoto 606-8501, Japan
| | - Y Takase
- Graduate School of Frontier Sciences, University of Tokyo, Kashiwa, Chiba 277-8561, Japan
| | - K Matsumoto
- Honda R&D Co., Ltd. Automobile R&D Center, Haga, Tochigi 321-3393, Japan
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9
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Yamasaki K, Fujisawa A, Nagashima Y. A proposal of Fourier-Bessel expansion with optimized ensembles of bases to analyse two dimensional image. Rev Sci Instrum 2017; 88:093507. [PMID: 28964170 DOI: 10.1063/1.5000744] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Accepted: 08/17/2017] [Indexed: 06/07/2023]
Abstract
It is a critical issue to find the best set of fitting function bases in mode structural analysis of two dimensional images like plasma emission profiles. The paper proposes a method to optimize a set of the bases in the case of Fourier-Bessel function series, using their orthonormal property, for more efficient and precise analysis. The method is applied on a tomography image of plasma emission obtained with the Maximum-likelihood expectation maximization method in a linear cylindrical device. The result demonstrates the excellency of the method that realizes the smaller residual error and minimum Akaike information criterion using smaller number of fitting function bases.
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Affiliation(s)
- K Yamasaki
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - A Fujisawa
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - Y Nagashima
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
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10
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Kuzmin A, Zushi H, Takagi I, Sharma S, Kobayashi M, Hirooka Y, Onchi T, Hanada K, Yoshida N, Nakamura K, Fujisawa A, Idei H, Nagashima Y, Hasegawa M, Mutoh T, Mishra K, Ohwada H. Spatial distribution of atomic and ion hydrogen flux and its effect on hydrogen recycling in long duration confined and non-confined plasmas. Nuclear Materials and Energy 2017. [DOI: 10.1016/j.nme.2017.03.027] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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11
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Matsuwaki T, Komatsuda M, Fujisawa A, Doke M, Yamanouchi K, Nishihara M. Molecular species of prostaglandins involved in modulating luteinising hormone pulses of female rats under infectious stress conditions. J Neuroendocrinol 2017; 29. [PMID: 28544399 DOI: 10.1111/jne.12490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 04/28/2017] [Accepted: 05/16/2017] [Indexed: 11/28/2022]
Abstract
Mammalian reproductive function is controlled by the hypothalamic-pituitary-gonadal (HPG) axis, which is suppressed under infectious stress conditions. By analysing the pulsatility of luteinising hormone (LH), we have previously demonstrated that prostaglandins (PGs) in the central nervous system mediate infectious stress to suppress the activity of the HPG axis. The present study aimed to characterise the types of PGs responsible for suppression of the HPG axis. We focused on three major types of PGs: PGE2 , PGD2 and PGF2α . We used female rats overiectomised bilaterally 1 week before the experiments. Lipopolysaccharide (100 μg kg-1 ) suppressed LH pulses at the same time as enhancing the concentration of all three PGs in the cerebrospinal fluid, which was restored by indomethacin (10 mg kg-1 ). Subsequently, we observed LH pulsatility after a single injection of each PG and after co-injection of PGE2 with PGF2α into the third cerebral ventricle. A single injection of PGE2 dose-dependently induced a transient increase in mean LH concentration and LH pulse amplitude, and PGD2 significantly increased the amplitude of LH pulses, wereas PGF2α did not affect LH pulsatility. On the other hand, co-injection of PGE2 and PGF2α induced a significant suppression of both the frequency and amplitude of LH pulses. These results suggest that PGE2 and PGF2α can represent two of the mediators that suppress the HPG axis in situations of infectious stress. Moreover, the results imply that there are two contradictory effects of PGE2 on LH pulsatility: (i) enhancive when working alone and (ii) suppressive when working together with PGF2α .
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Affiliation(s)
- T Matsuwaki
- Department of Veterinary Physiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - M Komatsuda
- Department of Veterinary Physiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - A Fujisawa
- Department of Veterinary Physiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - M Doke
- Department of Veterinary Physiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - K Yamanouchi
- Department of Veterinary Physiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - M Nishihara
- Department of Veterinary Physiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
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12
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Murata T, Honda T, Egawa G, Kitoh A, Dainichi T, Otsuka A, Nakajima S, Kore-eda S, Kaku Y, Nakamizo S, Endo Y, Fujisawa A, Miyachi Y, Kabashima K. Three-dimensional evaluation of subclinical extension of extramammary Paget disease: visualization of the histological border and its comparison to the clinical border. Br J Dermatol 2017; 177:229-237. [DOI: 10.1111/bjd.15282] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/14/2016] [Indexed: 02/01/2023]
Affiliation(s)
- T. Murata
- Department of Dermatology; Kyoto University Graduate School of Medicine; 54 Shogoin-Kawahara Sakyo-ku, Kyoto 606-8507 Japan
- Research Fellow of the Japan Society for the Promotion of Science
| | - T. Honda
- Department of Dermatology; Kyoto University Graduate School of Medicine; 54 Shogoin-Kawahara Sakyo-ku, Kyoto 606-8507 Japan
| | - G. Egawa
- Department of Dermatology; Kyoto University Graduate School of Medicine; 54 Shogoin-Kawahara Sakyo-ku, Kyoto 606-8507 Japan
| | - A. Kitoh
- Department of Dermatology; Kyoto University Graduate School of Medicine; 54 Shogoin-Kawahara Sakyo-ku, Kyoto 606-8507 Japan
| | - T. Dainichi
- Department of Dermatology; Kyoto University Graduate School of Medicine; 54 Shogoin-Kawahara Sakyo-ku, Kyoto 606-8507 Japan
| | - A. Otsuka
- Department of Dermatology; Kyoto University Graduate School of Medicine; 54 Shogoin-Kawahara Sakyo-ku, Kyoto 606-8507 Japan
| | - S. Nakajima
- Department of Dermatology; Kyoto University Graduate School of Medicine; 54 Shogoin-Kawahara Sakyo-ku, Kyoto 606-8507 Japan
| | | | - Y. Kaku
- Department of Dermatology; Kyoto University Graduate School of Medicine; 54 Shogoin-Kawahara Sakyo-ku, Kyoto 606-8507 Japan
| | - S. Nakamizo
- Department of Dermatology; Kyoto University Graduate School of Medicine; 54 Shogoin-Kawahara Sakyo-ku, Kyoto 606-8507 Japan
| | - Y. Endo
- Department of Dermatology; Kyoto University Graduate School of Medicine; 54 Shogoin-Kawahara Sakyo-ku, Kyoto 606-8507 Japan
| | - A. Fujisawa
- Department of Dermatology; Kyoto University Graduate School of Medicine; 54 Shogoin-Kawahara Sakyo-ku, Kyoto 606-8507 Japan
| | - Y. Miyachi
- Department of Dermatology; Kyoto University Graduate School of Medicine; 54 Shogoin-Kawahara Sakyo-ku, Kyoto 606-8507 Japan
| | - K. Kabashima
- Department of Dermatology; Kyoto University Graduate School of Medicine; 54 Shogoin-Kawahara Sakyo-ku, Kyoto 606-8507 Japan
- Singapore Immunology Network (SIgN) and Institute of Medical Biology; Agency for Science, Technology and Research (A*STAR); 8A Biomedical Grove, IMMUNOS Building #3-4 Biopolis 138648 Singapore
- PRESTO; Japan Science and Technology Agency; 4-1-8 Honcho Kawaguchi, Saitama 332-0012 Japan
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13
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Yokoyama M, Maassberg H, Beidler CD, Tribaldos V, Ida K, Castejón F, Estrada T, Fujisawa A, Minami T, Shimozuma T, Takeiri Y, Herranz J, Murakami S, Yamada H. Common Features of Core Electron-Root Confinement in Helical Devices. Fusion Science and Technology 2017. [DOI: 10.13182/fst06-a1254] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- M. Yokoyama
- National Institute for Fusion Science, Toki 509-5292, Japan
| | - H. Maassberg
- Max-Planck-Institut fur Plasmaphysik, Greifswald 17491, Germany
| | - C. D. Beidler
- Max-Planck-Institut fur Plasmaphysik, Greifswald 17491, Germany
| | - V. Tribaldos
- Laboratorio Nacional de Fusion, CIEMAT-FUSION, Madrid 28040, Spain
| | - K. Ida
- Max-Planck-Institut fur Plasmaphysik, Greifswald 17491, Germany
| | - F. Castejón
- Laboratorio Nacional de Fusion, CIEMAT-FUSION, Madrid 28040, Spain
| | - T. Estrada
- Laboratorio Nacional de Fusion, CIEMAT-FUSION, Madrid 28040, Spain
| | - A. Fujisawa
- National Institute for Fusion Science, Toki 509-5292, Japan
| | - T. Minami
- National Institute for Fusion Science, Toki 509-5292, Japan
| | - T. Shimozuma
- National Institute for Fusion Science, Toki 509-5292, Japan
| | - Y. Takeiri
- National Institute for Fusion Science, Toki 509-5292, Japan
| | - J. Herranz
- Laboratorio Nacional de Fusion, CIEMAT-FUSION, Madrid 28040, Spain
| | - S. Murakami
- Kyoto University, Department of Nuclear Engineering, Kyoto 606-8501, Japan
| | - H. Yamada
- National Institute for Fusion Science, Toki 509-5292, Japan
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14
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Irie H, Dainichi T, Fujita M, Endo Y, Fujisawa A, Tanioka M, Ishii N, Hashimoto T, Miyachi Y, Kabashima K. Anti-BP180 mucous membrane pemphigoid associated with acquired haemophilia A in a patient who suffered from life-threatening mucosal bleeding. J Eur Acad Dermatol Venereol 2016; 30:e199-e201. [PMID: 26616581 DOI: 10.1111/jdv.13525] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- H Irie
- Department of Dermatology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - T Dainichi
- Department of Dermatology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - M Fujita
- Department of Dermatology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Y Endo
- Department of Dermatology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - A Fujisawa
- Department of Dermatology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - M Tanioka
- Department of Dermatology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - N Ishii
- Department of Dermatology, Kurume University School of Medicine, Kurume, Fukuoka, Japan
| | - T Hashimoto
- Kurume University Institute of Cutaneous Cell Biology, Kurume, Fukuoka, Japan
| | - Y Miyachi
- Department of Dermatology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - K Kabashima
- Department of Dermatology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
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15
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Mitarai O, Nakamura K, Hasegawa M, Onchi T, Idei H, Fujisawa A, Hanada K, Zushi H, Higashijima A, Nakashima H, Kawasaki S, Matsuoka K, Koike S, Takahashi T, Tsutsui H. Comparative studies of inner and outer divertor discharges and a fueling study in QUEST. Fusion Engineering and Design 2016. [DOI: 10.1016/j.fusengdes.2015.12.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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16
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Honda Y, Otsuka A, Endo Y, Fujisawa A, Miyachi Y, Kabashima K. Pneumocephalus as a fatal complication of scalp angiosarcoma. J Eur Acad Dermatol Venereol 2016; 30:e40-e42. [PMID: 26332950 DOI: 10.1111/jdv.13287] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Y Honda
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - A Otsuka
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan.
| | - Y Endo
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - A Fujisawa
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Y Miyachi
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - K Kabashima
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan.
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17
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Zhao KJ, Nagashima Y, Diamond PH, Dong JQ, Itoh K, Itoh SI, Yan LW, Cheng J, Fujisawa A, Inagaki S, Kosuga Y, Sasaki M, Wang ZX, Wei L, Huang ZH, Yu DL, Hong WY, Li Q, Ji XQ, Song XM, Huang Y, Liu Y, Yang QW, Ding XT, Duan XR. Synchronization of Geodesic Acoustic Modes and Magnetic Fluctuations in Toroidal Plasmas. Phys Rev Lett 2016; 117:145002. [PMID: 27740841 DOI: 10.1103/physrevlett.117.145002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Indexed: 06/06/2023]
Abstract
The synchronization of geodesic acoustic modes (GAMs) and magnetic fluctuations is identified in the edge plasmas of the HL-2A tokamak. Mesoscale electric fluctuations (MSEFs) having components of a dominant GAM, and m/n=6/2 potential fluctuations are found at the same frequency as that of the magnetic fluctuations of m/n=6/2 (m and n are poloidal and toroidal mode numbers, respectively). The temporal evolutions of the MSEFs and the magnetic fluctuations clearly show the frequency entrainment and the phase lock between the GAM and the m/n=6/2 magnetic fluctuations. The results indicate that GAMs and magnetic fluctuations can transfer energy through nonlinear synchronization. Such nonlinear synchronization may also contribute to low-frequency zonal flow formation, reduction of turbulence level, and thus confinement regime transitions.
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Affiliation(s)
- K J Zhao
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
| | - Y Nagashima
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Kasuga koen 6-1, 816-8580, Japan
| | - P H Diamond
- Center for Momentum Transport and Flow Organization, University of California at San Diego, California, San Diego 92093, USA
| | - J Q Dong
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
- Institute for Fusion Theory and Simulation, Zhejiang University, Hangzhou 310027, China
| | - K Itoh
- National Institute for Fusion Science, Toki 509-5292, Japan
| | - S-I Itoh
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Kasuga koen 6-1, 816-8580, Japan
| | - L W Yan
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
| | - J Cheng
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
| | - A Fujisawa
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Kasuga koen 6-1, 816-8580, Japan
| | - S Inagaki
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Kasuga koen 6-1, 816-8580, Japan
| | - Y Kosuga
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Kasuga koen 6-1, 816-8580, Japan
| | - M Sasaki
- Research Institute for Applied Mechanics, Kyushu University, Kasuga, Kasuga koen 6-1, 816-8580, Japan
| | - Z X Wang
- School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024, China
| | - L Wei
- School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024, China
| | - Z H Huang
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
| | - D L Yu
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
| | - W Y Hong
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
| | - Q Li
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
| | - X Q Ji
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
| | - X M Song
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
| | - Y Huang
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
| | - Yi Liu
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
| | - Q W Yang
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
| | - X T Ding
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
| | - X R Duan
- Southwestern Institute of Physics, P.O. Box 432, Chendu 610041, China
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18
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Kanameishi S, Nakamizo S, Endo Y, Fujisawa A, Dainichi T, Tanaka T, Izawa K, Nishikomori R, Kabashima K. High level of serum human interleukin-18 in a patient with pyogenic arthritis, pyoderma gangrenosum and acne syndrome. J Eur Acad Dermatol Venereol 2016; 31:e115-e116. [PMID: 27505688 DOI: 10.1111/jdv.13856] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- S Kanameishi
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - S Nakamizo
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan.,Singapore Immunology Network (SIgN) and Institute of Medical Biology, Agency for Science, Technology and Research (A*STAR), Biopolis, Singapore
| | - Y Endo
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - A Fujisawa
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - T Dainichi
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - T Tanaka
- Department of Pediatrics, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - K Izawa
- Department of Pediatrics, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - R Nishikomori
- Department of Pediatrics, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - K Kabashima
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan.,Singapore Immunology Network (SIgN) and Institute of Medical Biology, Agency for Science, Technology and Research (A*STAR), Biopolis, Singapore
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19
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Kobayashi T, Itoh K, Ido T, Kamiya K, Itoh SI, Miura Y, Nagashima Y, Fujisawa A, Inagaki S, Ida K, Hoshino K. Experimental Identification of Electric Field Excitation Mechanisms in a Structural Transition of Tokamak Plasmas. Sci Rep 2016; 6:30720. [PMID: 27489128 PMCID: PMC4973265 DOI: 10.1038/srep30720] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 07/06/2016] [Indexed: 11/09/2022] Open
Abstract
Self-regulation between structure and turbulence, which is a fundamental process in the complex system, has been widely regarded as one of the central issues in modern physics. A typical example of that in magnetically confined plasmas is the Low confinement mode to High confinement mode (L-H) transition, which is intensely studied for more than thirty years since it provides a confinement improvement necessary for the realization of the fusion reactor. An essential issue in the L-H transition physics is the mechanism of the abrupt "radial" electric field generation in toroidal plasmas. To date, several models for the L-H transition have been proposed but the systematic experimental validation is still challenging. Here we report the systematic and quantitative model validations of the radial electric field excitation mechanism for the first time, using a data set of the turbulence and the radial electric field having a high spatiotemporal resolution. Examining time derivative of Poisson's equation, the sum of the loss-cone loss current and the neoclassical bulk viscosity current is found to behave as the experimentally observed radial current that excites the radial electric field within a few factors of magnitude.
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Affiliation(s)
- T. Kobayashi
- National Institute for Fusion Science, Toki 509-5292, Japan
| | - K. Itoh
- National Institute for Fusion Science, Toki 509-5292, Japan
- Research Center for Plasma Turbulence, Kyushu University, Kasuga 816-8580, Japan
| | - T. Ido
- National Institute for Fusion Science, Toki 509-5292, Japan
| | - K. Kamiya
- National Institutes for Quantum and Radiological Science and Technology, Naka 311-0193, Japan
| | - S.-I. Itoh
- Research Center for Plasma Turbulence, Kyushu University, Kasuga 816-8580, Japan
- Research Institute for Applied Mechanics, Kyushu University, Kasuga 816-8580, Japan
| | - Y. Miura
- Japan Atomic Energy Agency, Tokai 319-1184, Japan
| | - Y. Nagashima
- Research Center for Plasma Turbulence, Kyushu University, Kasuga 816-8580, Japan
- Research Institute for Applied Mechanics, Kyushu University, Kasuga 816-8580, Japan
| | - A. Fujisawa
- Research Center for Plasma Turbulence, Kyushu University, Kasuga 816-8580, Japan
- Research Institute for Applied Mechanics, Kyushu University, Kasuga 816-8580, Japan
| | - S. Inagaki
- Research Center for Plasma Turbulence, Kyushu University, Kasuga 816-8580, Japan
- Research Institute for Applied Mechanics, Kyushu University, Kasuga 816-8580, Japan
| | - K. Ida
- National Institute for Fusion Science, Toki 509-5292, Japan
- Research Center for Plasma Turbulence, Kyushu University, Kasuga 816-8580, Japan
| | - K. Hoshino
- National Institutes for Quantum and Radiological Science and Technology, Naka 311-0193, Japan
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20
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Inagaki S, Kobayashi T, Kosuga Y, Itoh SI, Mitsuzono T, Nagashima Y, Arakawa H, Yamada T, Miwa Y, Kasuya N, Sasaki M, Lesur M, Fujisawa A, Itoh K. A Concept of Cross-Ferroic Plasma Turbulence. Sci Rep 2016; 6:22189. [PMID: 26917218 PMCID: PMC4768185 DOI: 10.1038/srep22189] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 02/08/2016] [Indexed: 11/18/2022] Open
Abstract
The variety of scalar and vector fields in laboratory and nature plasmas is formed by plasma turbulence. Drift-wave fluctuations, driven by density gradients in magnetized plasmas, are known to relax the density gradient while they can generate flows. On the other hand, the sheared flow in the direction of magnetic fields causes Kelvin-Helmholtz type instabilities, which mix particle and momentum. These different types of fluctuations coexist in laboratory and nature, so that the multiple mechanisms for structural formation exist in extremely non-equilibrium plasmas. Here we report the discovery of a new order in plasma turbulence, in which chained structure formation is realized by cross-interaction between inhomogeneities of scalar and vector fields. The concept of cross-ferroic turbulence is developed, and the causal relation in the multiple mechanisms behind structural formation is identified, by measuring the relaxation rate and dissipation power caused by the complex turbulence-driven flux.
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Affiliation(s)
- S Inagaki
- Research Institute for Applied Mechanics, Kyushu University, 6-1 Kasuga-Koen, Kasuga-city, Fukuoka 816-8580, Japan.,Research Center for Plasma Turbulence, Kyushu University, 6-1 Kasuga-Koen, Kasuga-city, Fukuoka 816-8580 Japan
| | - T Kobayashi
- National Institute for Fusion Science, 322-6 Oroshi-cho, Toki-city, Gifu 509-5292, Japan
| | - Y Kosuga
- Institute for Advanced Study, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, 812-8581, Fukuoka Japan
| | - S-I Itoh
- Research Institute for Applied Mechanics, Kyushu University, 6-1 Kasuga-Koen, Kasuga-city, Fukuoka 816-8580, Japan.,Research Center for Plasma Turbulence, Kyushu University, 6-1 Kasuga-Koen, Kasuga-city, Fukuoka 816-8580 Japan
| | - T Mitsuzono
- Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, 6-1 Kasuga-Koen, Kasuga-city, Fukuoka 816-8580, Japan
| | - Y Nagashima
- Research Institute for Applied Mechanics, Kyushu University, 6-1 Kasuga-Koen, Kasuga-city, Fukuoka 816-8580, Japan.,Research Center for Plasma Turbulence, Kyushu University, 6-1 Kasuga-Koen, Kasuga-city, Fukuoka 816-8580 Japan
| | - H Arakawa
- Teikyo University, 6-22 Misaki-machi, Omuta-city, Fukuoka 836-8505, Japan
| | - T Yamada
- Faculty of Arts and Science, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Y Miwa
- Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, 6-1 Kasuga-Koen, Kasuga-city, Fukuoka 816-8580, Japan
| | - N Kasuya
- Research Institute for Applied Mechanics, Kyushu University, 6-1 Kasuga-Koen, Kasuga-city, Fukuoka 816-8580, Japan.,Research Center for Plasma Turbulence, Kyushu University, 6-1 Kasuga-Koen, Kasuga-city, Fukuoka 816-8580 Japan
| | - M Sasaki
- Research Institute for Applied Mechanics, Kyushu University, 6-1 Kasuga-Koen, Kasuga-city, Fukuoka 816-8580, Japan.,Research Center for Plasma Turbulence, Kyushu University, 6-1 Kasuga-Koen, Kasuga-city, Fukuoka 816-8580 Japan
| | - M Lesur
- Research Institute for Applied Mechanics, Kyushu University, 6-1 Kasuga-Koen, Kasuga-city, Fukuoka 816-8580, Japan
| | - A Fujisawa
- Research Institute for Applied Mechanics, Kyushu University, 6-1 Kasuga-Koen, Kasuga-city, Fukuoka 816-8580, Japan.,Research Center for Plasma Turbulence, Kyushu University, 6-1 Kasuga-Koen, Kasuga-city, Fukuoka 816-8580 Japan
| | - K Itoh
- Research Center for Plasma Turbulence, Kyushu University, 6-1 Kasuga-Koen, Kasuga-city, Fukuoka 816-8580 Japan.,National Institute for Fusion Science, 322-6 Oroshi-cho, Toki-city, Gifu 509-5292, Japan
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21
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Anegawa H, Otsuka A, Kaku Y, Nonomura Y, Fujisawa A, Endo Y, Kabashima K. Upregulation of granzyme B and interferon-γ mRNA in responding lesions by treatment with nivolumab for metastatic melanoma: a case report. J Eur Acad Dermatol Venereol 2016; 30:e231-e232. [PMID: 26837059 DOI: 10.1111/jdv.13567] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- H Anegawa
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - A Otsuka
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Y Kaku
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Y Nonomura
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - A Fujisawa
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Y Endo
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - K Kabashima
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan
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22
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Kanameishi S, Otsuka A, Nonomura Y, Fujisawa A, Endo Y, Kabashima K. Idiopathic thrombocytopenic purpura induced by nivolumab in a metastatic melanoma patient with elevated PD-1 expression on B cells. Ann Oncol 2015; 27:546-7. [PMID: 26602778 DOI: 10.1093/annonc/mdv580] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Affiliation(s)
- S Kanameishi
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - A Otsuka
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Y Nonomura
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - A Fujisawa
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Y Endo
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - K Kabashima
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan
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23
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Banerjee S, Zushi H, Nishino N, Mishra K, Onchi T, Kuzmin A, Nagashima Y, Hanada K, Nakamura K, Idei H, Hasegawa M, Fujisawa A. Dynamical programming based turbulence velocimetry for fast visible imaging of tokamak plasma. Rev Sci Instrum 2015; 86:033505. [PMID: 25832227 DOI: 10.1063/1.4914838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
An orthogonal dynamic programming (ODP) based particle image velocimetry (PIV) technique is developed to measure the time resolved flow field of the fluctuating structures at the plasma edge and scrape off layer (SOL) of tokamaks. This non-intrusive technique can provide two dimensional velocity fields at high spatial and temporal resolution from a fast framing image sequence and hence can provide better insights into plasma flow as compared to conventional probe measurements. Applicability of the technique is tested with simulated image pairs. Finally, it is applied to tangential fast visible images of QUEST plasma to estimate the SOL flow in inboard poloidal null-natural divertor configuration. This technique is also applied to investigate the intricate features of the core of the run-away dominated phase following the injection of a large amount of neutrals in the target Ohmic plasma. Development of the ODP-PIV code and its applicability on actual plasma images is reported.
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Affiliation(s)
- Santanu Banerjee
- Institute for Plasma Research, Bhat, Gandhinagar 382428, Gujarat, India
| | - H Zushi
- RIAM, Kyushu University, 6-1 Kasuga Koen, Kasuga-shi, Fukuoka 816-8580, Japan
| | - N Nishino
- Mechanical System Engineering, Hiroshima University, Hiroshima 739-8527, Japan
| | - K Mishra
- IGSES, Kyushu University, 6-1 Kasuga Koen, Kasuga-shi, Fukuoka 816-8580, Japan
| | - T Onchi
- RIAM, Kyushu University, 6-1 Kasuga Koen, Kasuga-shi, Fukuoka 816-8580, Japan
| | - A Kuzmin
- RIAM, Kyushu University, 6-1 Kasuga Koen, Kasuga-shi, Fukuoka 816-8580, Japan
| | - Y Nagashima
- RIAM, Kyushu University, 6-1 Kasuga Koen, Kasuga-shi, Fukuoka 816-8580, Japan
| | - K Hanada
- RIAM, Kyushu University, 6-1 Kasuga Koen, Kasuga-shi, Fukuoka 816-8580, Japan
| | - K Nakamura
- RIAM, Kyushu University, 6-1 Kasuga Koen, Kasuga-shi, Fukuoka 816-8580, Japan
| | - H Idei
- RIAM, Kyushu University, 6-1 Kasuga Koen, Kasuga-shi, Fukuoka 816-8580, Japan
| | - M Hasegawa
- RIAM, Kyushu University, 6-1 Kasuga Koen, Kasuga-shi, Fukuoka 816-8580, Japan
| | - A Fujisawa
- RIAM, Kyushu University, 6-1 Kasuga Koen, Kasuga-shi, Fukuoka 816-8580, Japan
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24
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Onchi T, Fujisawa A, Sanpei A. A prototype diagnostics system to detect ultraviolet emission for plasma turbulence. Rev Sci Instrum 2014; 85:113502. [PMID: 25430111 DOI: 10.1063/1.4900660] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A system to detect ultraviolet emissions from plasma is developed for multi-point measurement, the target of which is the imaging of turbulence with a high temporal resolution. A fluorescent glass, which converts ultraviolet emissions to visible light with a wavelength of approximately 540 nm, is utilized in the system. Following the conversion, the fluorescent light is transferred with fibre optics, and is converted to electric signals in a location that is sufficiently distant from an electrically noisy environment around the plasma device. This paper describes a prototype system of this diagnostic method and discusses the spectral analysis obtained using a low-aspect-ratio reversed field pinch RELAX.
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Affiliation(s)
- T Onchi
- Research Institute for Applied Mechanics, Kyushu University, 6-1, Kasuga Kohen, Kasuga, Fukuoka 816-8580, Japan
| | - A Fujisawa
- Research Institute for Applied Mechanics, Kyushu University, 6-1, Kasuga Kohen, Kasuga, Fukuoka 816-8580, Japan
| | - A Sanpei
- Department of Electronics, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, Kyoto 606-8585, Japan
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25
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Mishra K, Idei H, Zushi H, Nagata K, Akimoto R, Yamamoto MK, Hanada K, Hasegawa M, Nakamura K, Fujisawa A, Nagashima Y, Banerjee S, Onchi T, Kuzmin A. Thermal imaging of plasma with a phased array antenna in QUEST. Rev Sci Instrum 2014; 85:11E808. [PMID: 25430373 DOI: 10.1063/1.4889903] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A thermal imaging system to measure plasma Electron Bernstein Emission (EBE) emanating from the mode conversion region in overdense plasma is discussed. Unlike conventional ECE/EBE imaging, this diagnostics does not employ any active mechanical scanning mirrors or focusing optics to scan for the emission cones in plasma. Instead, a standard 3 × 3 waveguide array antenna is used as a passive receiver to collect emission from plasma and imaging reconstruction is done by accurate measurements of phase and intensity of these signals by heterodyne detection technique. A broadband noise source simulating the EBE, is installed near the expected mode conversion region and its position is successfully reconstructed using phase array technique which is done in post processing.
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Affiliation(s)
- Kishore Mishra
- IGSES, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - H Idei
- RIAM, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - H Zushi
- RIAM, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - K Nagata
- IGSES, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - R Akimoto
- IGSES, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - M K Yamamoto
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji 611-0011, Japan
| | - K Hanada
- RIAM, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - M Hasegawa
- RIAM, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - K Nakamura
- RIAM, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - A Fujisawa
- RIAM, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - Y Nagashima
- RIAM, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - S Banerjee
- IGSES, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - T Onchi
- RIAM, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
| | - A Kuzmin
- RIAM, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
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26
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Hasegawa M, Nakamura K, Zushi H, Hanada K, Fujisawa A, Matsuoka K, Mitarai O, Idei H, Nagashima Y, Tokunaga K, Kawasaki S, Nakashima H, Higashijima A. Development of plasma control system for divertor configuration on QUEST. Fusion Engineering and Design 2013. [DOI: 10.1016/j.fusengdes.2013.03.035] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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27
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Kobayashi T, Itoh K, Ido T, Kamiya K, Itoh SI, Miura Y, Nagashima Y, Fujisawa A, Inagaki S, Ida K, Hoshino K. Spatiotemporal structures of edge limit-cycle oscillation before L-to-H transition in the JFT-2M tokamak. Phys Rev Lett 2013; 111:035002. [PMID: 23909334 DOI: 10.1103/physrevlett.111.035002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Indexed: 06/02/2023]
Abstract
In this Letter, we report analyses of spatiotemporal dynamics of turbulence and structure in the limit-cycle oscillation (LCO) that precedes an L-to-H transition. Zonal flows are not observed during LCO, and the oscillation is the periodic generations or decays of barrier with edge-localized mean flow. Oscillatory Reynolds stress is found to be too small to accelerate the LCO flow, by considering the dielectric constant in magnetized toroidal plasmas. Propagation of changes of the density gradient and turbulence amplitude into the core is also observed.
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Affiliation(s)
- T Kobayashi
- Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, Kasuga 816-8580, Japan.
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28
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Tokunaga M, Endo Y, Fujisawa A, Tanioka M, Nomura T, Miyachi Y. Improvement in telangiectatic rosacea as a side-effect of monthly docetaxel therapy. Clin Exp Dermatol 2013; 39:262-3. [PMID: 23763600 DOI: 10.1111/ced.12180] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/14/2013] [Indexed: 12/24/2022]
Affiliation(s)
- M Tokunaga
- Department of Dermatology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
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29
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Ono S, Tanioka M, Tanizaki H, Fujisawa A, Koga H, Hashimoto T, Kamiya K, Aoyama Y, Iwatsuki K, Miyachi Y. Concurrence of autoantibodies to bullous pemphigoid antigens and desmoglein 3: analysis of pathogenic and nonpathogenic antibodies. Br J Dermatol 2013; 168:1357-60. [PMID: 23738642 DOI: 10.1111/bjd.12143] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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30
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Banerjee S, Zushi H, Nishino N, Nagashima Y, Hanada K, Ishiguro M, Ryoukai T, Tashima S, Inoue T, Nakamura K, Idei H, Hasegawa M, Fujisawa A, Matsuoka K. Fast visible imaging and edge turbulence analysis in QUEST. Rev Sci Instrum 2012; 83:10E524. [PMID: 23127031 DOI: 10.1063/1.4739080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A fast visible imaging system is installed on the spherical tokamak QUEST to study edge turbulence. The camera uses a complementary metal-oxide semiconductor detector with a maximum resolution of 1024 × 1024 at 7000 frames∕s (fps) and can achieve 775 kfps at a resolution of 128 × 24. In this paper, we present the salient features of the system and its application to study edge turbulence in 8.2 GHz ECRH driven slab plasma, without plasma current. Vertical magnetic field (B(z)) topology is varied with three sets of poloidal field (PF) coils and the variation in the edge turbulence is investigated as a function of the B(z) strength and curvature. Fluctuation amplitude was highest for the shallow PF well. Cross-correlation coefficient shows distinct coherent mode along z direction at the steep density gradient region and it grows with the PF mirror ratio.
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31
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Sharma S, Zushi H, Yoshida N, Watanabe H, Osakabe M, Takeri Y, Hasegawa M, Tanabe T, Tokunaga K, Hanada K, Idei H, Sakamoto M, Nakamura K, Fujisawa A, Ishiguro M, Tashima S. Analysis of PWI footprint traces and material damage on the first walls of the spherical tokamak QUEST. Fusion Engineering and Design 2012. [DOI: 10.1016/j.fusengdes.2011.10.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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32
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Ichihara A, Jinnin M, Yamane K, Fujisawa A, Sakai K, Masuguchi S, Fukushima S, Maruo K, Ihn H. microRNA-mediated keratinocyte hyperproliferation in psoriasis vulgaris. Br J Dermatol 2011; 165:1003-10. [PMID: 21711342 DOI: 10.1111/j.1365-2133.2011.10497.x] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
BACKGROUND Psoriasis is a chronic inflammatory skin disease characterized by intense proliferation and abnormal differentiation of keratinocytes, although the pathogenesis is still not completely clarified. OBJECTIVES We investigated the mechanism of keratinocyte proliferation seen in psoriasis, focusing on microRNA (miRNA). MATERIALS AND METHODS miRNAs were extracted from tissues and sera of psoriasis, atopic dermatitis and healthy control. To determine pathogenic miRNAs, we performed miRNA polymerase chain reaction (PCR) array analysis. The results were confirmed with quantitative real-time PCR, in situ hybridization, immunohistochemistry, transient transfection of siRNA and inhibitor in cultured keratinocytes and Western blotting. RESULTS PCR array analysis using tissue miRNA demonstrated miR-424 level was markedly decreased in psoriasis skin in vivo. Protein expression of mitogen-activated protein kinase kinase 1 (MEK1) or cyclin E1, predicted target genes of miR-424, was increased in psoriatic skin, although their mRNA levels were not. The transfection of specific inhibitor of miR-424 in normal human keratinocytes led to upregulation of MEK1 or cyclin E1 protein, and resulted in increased cell proliferation. On the other hand, cell number was significantly decreased when cells were transfected with siRNA for MEK1 or cyclin E1. Furthermore, we first investigated serum miRNA levels in psoriasis. Although not significant, serum miR-424 concentration tended to be decreased in patients with psoriasis compared with healthy controls. CONCLUSIONS Decreased miR-424 expression and subsequently increased MEK1 or cyclin E1 may play a key role in the pathogenesis of psoriasis. Investigation of the regulatory mechanisms of keratinocyte proliferation by miRNA may lead to new treatments and a disease activity marker.
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Affiliation(s)
- A Ichihara
- Department of Dermatology and Plastic Surgery, Faculty of Life Sciences, Kumamoto University, Kumamoto 860-8556, Japan
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Inagaki S, Tokuzawa T, Itoh K, Ida K, Itoh SI, Tamura N, Sakakibara S, Kasuya N, Fujisawa A, Kubo S, Shimozuma T, Ido T, Nishimura S, Arakawa H, Kobayashi T, Tanaka K, Nagayama Y, Kawahata K, Sudo S, Yamada H, Komori A. Observation of long-distance radial correlation in toroidal plasma turbulence. Phys Rev Lett 2011; 107:115001. [PMID: 22026678 DOI: 10.1103/physrevlett.107.115001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2010] [Indexed: 05/31/2023]
Abstract
This Letter presents the discovery of macroscale electron temperature fluctuations with a long radial correlation length comparable to the plasma minor radius in a toroidal plasma. Their spatiotemporal structure is characterized by a low frequency of ∼1-3 kHz, ballistic radial propagation, a poloidal or toroidal mode number of m/n=1/1 (or 2/1), and an amplitude of ∼2% at maximum. Nonlinear coupling between the long-range fluctuations and the microscopic fluctuations is identified. A change of the amplitude of the long-range fluctuation is transmitted across the plasma radius at the velocity which is of the order of the drift velocity.
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Affiliation(s)
- S Inagaki
- Research Institute for Applied Mechanics, Kyushu University, Fukuoka 816-8580, Japan
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34
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Yamada T, Itoh SI, Inagaki S, Nagashima Y, Kasuya N, Kamataki K, Arakawa H, Kobayashi T, Yagi M, Fujisawa A, Itoh K. Observation of quasi-two-dimensional nonlinear interactions in a drift-wave streamer. Phys Rev Lett 2010; 105:225002. [PMID: 21231392 DOI: 10.1103/physrevlett.105.225002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2010] [Indexed: 05/30/2023]
Abstract
A streamer, which is a bunching of drift-wave fluctuations, and its mediator, which generates the streamer by coupling with other fluctuations, have been observed in a cylindrical magnetized plasma. Their radial structures were investigated in detail by using the biphase analysis. Their quasi-two-dimensional structures were revealed to be equivalent with a pair of fast and slow modes predicted by a nonlinear Schrödinger equation based on the Hasegawa-Mima model.
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Affiliation(s)
- T Yamada
- Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba 277-8561, Japan.
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35
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Makino T, Jinnin M, Muchemwa F, Fukushima S, Kogushi-Nishi H, Moriya C, Igata T, Fujisawa A, Johno T, Ihn H. Basic fibroblast growth factor stimulates the proliferation of human dermal fibroblasts via the ERK1/2 and JNK pathways. Br J Dermatol 2009; 162:717-23. [DOI: 10.1111/j.1365-2133.2009.09581.x] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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36
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Yamada T, Nagashima Y, Inagaki S, Kawai Y, Yagi M, Itoh SI, Maruta T, Shinohara S, Terasaka K, Kawaguchi M, Fukao M, Fujisawa A, Itoh K. Fine positioning of a poloidal probe array. Rev Sci Instrum 2007; 78:123501. [PMID: 18163726 DOI: 10.1063/1.2818796] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Multipoint detection is an essential requirement for investigating plasma turbulence which is a highly nonlinear phenomenon in space and time. We have fabricated an array of 64-channel poloidal probes surrounding the linear cylindrical plasma named LMD-U in order to study turbulence properties, particularly the nonlinear mode couplings, in the domain of poloidal wave number and frequency. However, misalignments of probe tips produce spurious modes, which do not exist in the real plasma, to distort the precise wave number measurements. The paper presents the description of the 64-channel poloidal probe array with means to adjust the probe positions, with discussion on the effects of the misalignments on the wave number measurements.
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Affiliation(s)
- T Yamada
- Research Institute for Applied Mechanics, Kyushu University, Kasuga 816-8580, Japan.
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37
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Nakano H, Fujisawa A, Shimizu A, Ohshima S, Iguchi H, Yoshimura Y, Minami T. Reconstruction method of local density fluctuation for heavy ion beam probe measurements. Rev Sci Instrum 2007; 78:063502. [PMID: 17614607 DOI: 10.1063/1.2745233] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Heavy ion beam probe (HIBP) is an excellent diagnostic to measure the density and potential fluctuations simultaneously in magnetically confined plasmas. However, it has been well known that the density fluctuation measured with the HIBP is not local but contains the fluctuations along the beam orbits. In this article, a method is proposed to evaluate local density fluctuation in the HIBP measurements by removing the well-known path integral effects. The reconstructed density fluctuation amplitude and power spectrum are shown, for example, by applying the proposed method on the density fluctuation measurement data obtained in a toroidal helical plasma, Compact Helical System.
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Affiliation(s)
- H Nakano
- National Institute for Fusion Science, Oroshi-cho, Toki 509-5292, Japan
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38
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Fujisawa A, Itoh K, Shimizu A, Nakano H, Ohshima S, Iguchi H, Matsuoka K, Okamura S, Minami T, Yoshimura Y, Nagaoka K, Ida K, Toi K, Takahashi C, Kojima M, Nishimura S, Isobe M, Suzuki C, Akiyama T, Nagashima Y, Itoh SI, Diamond PH. Experimental evidence of a zonal magnetic field in a toroidal plasma. Phys Rev Lett 2007; 98:165001. [PMID: 17501426 DOI: 10.1103/physrevlett.98.165001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2006] [Indexed: 05/15/2023]
Abstract
A zonal magnetic field is found in a toroidal plasma. The magnetic field has a symmetric bandlike structure, which is uniform in the toroidal and poloidal directions and varies radially with a finite wavelength of mesoscale, which is analogous to zonal flows. A time-dependent bicoherence analysis reveals that the magnetic field should be generated by the background plasma turbulence. The discovery is classified as a new kind of phenomenon of structured magnetic field generation, giving insight into phenomena such as dipole field generation in rotational planets.
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Affiliation(s)
- A Fujisawa
- National Institute for Fusion Science, Oroshi-cho, Toki-shi 509-52, Japan
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39
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Okamura S, Akiyama T, Fujisawa A, Ida K, Iguchi H, Isobe M, Kado S, Minami T, Nagaoka K, Nakamura K, Nishimura S, Matsuoka K, Matsushita H, Nakano H, Ohshima S, Oishi T, Shimizu A, Suzuki C, Takahashi C, Toi K, Yoshimura Y, Yoshinu M. Improved Confinement and Related Physics Study in the Compact Helical System. Fusion Science and Technology 2007. [DOI: 10.13182/fst07-a1286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- S. Okamura
- National Institute for Fusion Science, Oroshi 322-6, Toki 509-5292, Japan
| | - T. Akiyama
- National Institute for Fusion Science, Oroshi 322-6, Toki 509-5292, Japan
| | - A. Fujisawa
- National Institute for Fusion Science, Oroshi 322-6, Toki 509-5292, Japan
| | - K. Ida
- National Institute for Fusion Science, Oroshi 322-6, Toki 509-5292, Japan
| | - H. Iguchi
- National Institute for Fusion Science, Oroshi 322-6, Toki 509-5292, Japan
| | - M. Isobe
- National Institute for Fusion Science, Oroshi 322-6, Toki 509-5292, Japan
| | - S. Kado
- The University of Tokyo, High-Temperature Plasma Center, 5-1-5 Kashiwanoha, Kashiwa, Chiba 227-8568, Japan
| | - T. Minami
- National Institute for Fusion Science, Oroshi 322-6, Toki 509-5292, Japan
| | - K. Nagaoka
- National Institute for Fusion Science, Oroshi 322-6, Toki 509-5292, Japan
| | - K. Nakamura
- National Institute for Fusion Science, Oroshi 322-6, Toki 509-5292, Japan
| | - S. Nishimura
- National Institute for Fusion Science, Oroshi 322-6, Toki 509-5292, Japan
| | - K. Matsuoka
- National Institute for Fusion Science, Oroshi 322-6, Toki 509-5292, Japan
| | - H. Matsushita
- National Institute for Fusion Science, Oroshi 322-6, Toki 509-5292, Japan
| | - H. Nakano
- National Institute for Fusion Science, Oroshi 322-6, Toki 509-5292, Japan
| | - S. Ohshima
- National Institute for Fusion Science, Oroshi 322-6, Toki 509-5292, Japan
| | - T. Oishi
- The University of Tokyo, Graduate School of Engineering, Department of Quantum Engineering and System Science Hongo 7-3-1, Tokyo 113-8656, Japan
| | - A. Shimizu
- National Institute for Fusion Science, Oroshi 322-6, Toki 509-5292, Japan
| | - C. Suzuki
- National Institute for Fusion Science, Oroshi 322-6, Toki 509-5292, Japan
| | - C. Takahashi
- National Institute for Fusion Science, Oroshi 322-6, Toki 509-5292, Japan
| | - K. Toi
- National Institute for Fusion Science, Oroshi 322-6, Toki 509-5292, Japan
| | - Y. Yoshimura
- National Institute for Fusion Science, Oroshi 322-6, Toki 509-5292, Japan
| | - M. Yoshinu
- National Institute for Fusion Science, Oroshi 322-6, Toki 509-5292, Japan
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40
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Uehara M, Shibahara K, Fujita S, Tobita T, Ohba S, Fujisawa A, Nonaka M, Inokuchi T. Epithelioid hemangioendothelioma of tongue: A case report with immunohistochemical studies. ACTA ACUST UNITED AC 2006. [DOI: 10.1016/j.ooe.2005.09.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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41
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Nonaka M, Ikeda H, Fujisawa A, Uehara M, Inokuchi T. Induction of apoptosis by paclitaxel in human oral carcinoma cells. Int J Oral Maxillofac Surg 2006; 35:649-52. [PMID: 16513327 DOI: 10.1016/j.ijom.2006.01.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2005] [Revised: 08/19/2005] [Accepted: 01/16/2006] [Indexed: 11/24/2022]
Abstract
The present study investigated induction of apoptosis in NB-1 oral carcinoma cells by paclitaxel and the expression of Bcl-2 and Bax in relation to this apoptotic cell death. Paclitaxel induced apoptotic cell death in NB-1 cells in a dose- and a time-dependent manner. The present results suggest that paclitaxel can induce apoptosis of NB-1 cells, which may be mediated by down-regulation of Bcl-2 together with up-regulation of Bax.
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Affiliation(s)
- M Nonaka
- Department of Developmental and Reconstructive Medicine, Division of Oral & Maxillofacial Surgical Reconstruction and Functional Restoration, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8588, Japan.
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42
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Fujisawa A, Itoh K, Iguchi H, Matsuoka K, Okamura S, Shimizu A, Minami T, Yoshimura Y, Nagaoka K, Takahashi C, Kojima M, Nakano H, Ohsima S, Nishimura S, Isobe M, Suzuki C, Akiyama T, Ida K, Toi K, Itoh SI, Diamond PH. Identification of zonal flows in a toroidal plasma. Phys Rev Lett 2004; 93:165002. [PMID: 15524996 DOI: 10.1103/physrevlett.93.165002] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2004] [Indexed: 05/24/2023]
Abstract
This Letter presents experimental confirmation of the presence of zonal flows in magnetically confined toroidal plasma using an advanced diagnostic system--dual heavy ion beam probes. The simultaneous observation of an electric field at two distant toroidal locations (approximately 1.5 m apart) in the high temperature (approximately 1 keV) plasma provides a fluctuation spectrum of electric field (or flow), a spatiotemporal structure of the zonal flows (characteristic radial length of approximately 1.5 cm and lifetime of approximately 1.5 ms), their long-range correlation with toroidal symmetry (n=0), and the difference in the zonal flow amplitude with and without a transport barrier. These constitute essential elements of turbulence-zonal flow systems, and illustrate one of the fundamental processes of structure formation in nature.
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Affiliation(s)
- A Fujisawa
- National Institute for Fusion Science, Oroshi-cho, Toki-shi, 509-52 Japan
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43
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Yamamoto Y, Fujisawa A, Hara A, Dunlap WC. An unusual vitamin E constituent (alpha-tocomonoenol) provides enhanced antioxidant protection in marine organisms adapted to cold-water environments. Proc Natl Acad Sci U S A 2001; 98:13144-8. [PMID: 11687648 PMCID: PMC60838 DOI: 10.1073/pnas.241024298] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A new vitamin E constituent having an unusual methylene unsaturation at the isoprenoid-chain terminus of alpha-tocopherol (alpha-Toc) was isolated from chum salmon eggs and was found to have identical antioxidant activity as does alpha-Toc in methanol or liposomal suspension at 37 degrees C. Here we report that this marine-derived tocopherol (MDT) is broadly distributed with alpha-Toc in the tissue of marine fish, and that the MDT composition of total vitamin E is greater in the flesh of cold-water salmon (12-20%) than in that of tropical fish (< or =2.5%). Vitamin E analysis of cultured masu salmon maintained on a MDT-deplete diet showed substantially less MDT content than native masu salmon, suggesting a trophic origin of MDT. This contention is supported by the finding of MDT in marine plankton from the cold waters of Hokkaido. We found that MDT inhibited peroxidation of cholesterol-containing phosphatidylcholine liposomes to a greater extent than did alpha-Toc at 0 degrees C. Furthermore, the ratios of the rate constants for MDT and alpha-Toc to scavenge peroxyl radicals increased with decreasing rates of radical flux in liposomes and fish oil at 0 degrees C, indicating that the enhanced activity of MDT at low temperature is attributed to its greater rate of diffusion in viscous lipids. These results suggest that MDT production, or its trophic accumulation, may reduce lipid peroxidation in marine organisms functionally adapted to cold-water environments.
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Affiliation(s)
- Y Yamamoto
- Department of Chemistry and Biotechnology, School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
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44
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Ikeda H, Kitamura A, Uehara M, Tobita T, Ohba S, Nonaka M, Fujisawa A, Inokuchi T. [A case of squamous cell carcinoma of the oral floor showing a complete response to oral administration of UFT]. Gan To Kagaku Ryoho 2001; 28:1929-31. [PMID: 11729490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
A 73-year-old male with squamous cell carcinoma of the oral floor (T1N0M0), who had not consented to radical treatment was treated with UFT by oral administration alone. After commencement of the administration, tumor remission was observed at 2 weeks and disappeared clinically at 8 weeks. The total period of oral administration of UFT was twenty-three months, and the total dose was 186.5 g as tegafur. Major adverse effects were pigmentation of hands and liver dysfunction. He remains under observation, and there is no evidence of tumor recurrence.
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Affiliation(s)
- H Ikeda
- Second Dept. of Oral and Maxillofacial Surgery, Nagasaki University School of Dentistry
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45
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Abstract
The blood-contacting surface, mainly composed of polycarbonate, of the Gyro C1E3 pump was modified using plasma glow discharge to introduce a carboxyl functional group, coated with a base layer of polyethyleneimine as a linker, and coupled with heparin by multi-ionic binding to enhance blood compatibility. A relative surface content of 3.7% sulfur, which demonstrated heparin immobilization on the polycarbonate substrate, was observed on x-ray photoelectron spectroscopy, and a initial bioactivity of approximately 88.5 +/- 7.3 mIU/cm2 was obtained by the chromogenic method for antifactor Xa assay. Furthermore, in vitro observation of platelet and fibrin adherence using bovine blood under dynamic flow conditions for 6 h revealed that the multi-ionically heparinized Gyro C1E3 had significantly stronger antithrombogenecity than the noncoated original type which was evaluated as a good hemocompatible blood pump for clinical use. Not only the Gyro C1E3 but also the ionically heparin-coated Gyro pump are expected to be thromboresistant in clinical use.
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Affiliation(s)
- K Muramatsu
- Research and Development Department, Bioceram Division, Kyocera Corporation, 10-1, Kawai, Gamo-cho, Shiga 529-1595, Japan.
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46
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Ida K, Minami T, Yoshimura Y, Fujisawa A, Suzuki C, Okamura S, Nishimura S, Isobe M, Iguchi H, Itoh K, Kado S, Liang Y, Nomura I, Osakabe M, Takahashi C, Tanaka K, Matsuoka K. Observation of toroidal flow antiparallel to the <E(r) x B(straight theta)> drift direction in the hot electron mode plasmas in the compact helical system. Phys Rev Lett 2001; 86:3040-3043. [PMID: 11290102 DOI: 10.1103/physrevlett.86.3040] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2000] [Indexed: 05/23/2023]
Abstract
A toroidal flow antiparallel to the <E(r) x B(straight theta)> drift direction is observed in the hot electron mode plasmas when a large positive electric field and a sharp electron temperature gradient are sustained inside the internal transport barrier in the Compact Helical System. This toroidal flow reaches up to 5x10(4) m/s at the plasma center, and it is large enough to reverse the toroidal flow driven by a tangentially injected neutral beam. These observations clearly show the plasma favors flow in the minimum nablaB direction at the transport barrier.
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Affiliation(s)
- K Ida
- National Institute for Fusion Science, Toki 509-5292, Japan
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47
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Abstract
PURPOSE To evaluate the clinical aspects of patients with primary cornea guttata and the specular microscopical findings/morphology in their corneal endothelial cells. METHODS Twenty-three patients consulting Kanazawa Medical University Hospital or related hospitals in Ishikawa or Fukui prefectures and diagnosed with primary cornea guttata by slit-lamp examination underwent an analysis of their clinical features and corneal endothelial cells. RESULTS Most cases were middle-aged to elderly women. None of them complained of visual impairment due to cornea guttata. The 46 eyes of these cases were included in this study. Specular microscopical findings revealed that the size and density of dark areas varied, with asymmetry noted in some cases. The parameters of the endothelial cells comprising mean cell area, the proportion of hexagonal cells, and the coefficient of variation, were almost within normal limits except for 1 eye of a 79-year-old man who was speculated to be at an early stage of Fuchs endothelial corneal dystrophy. Three cases had undergone cataract surgery, but did not show significant changes in endothelial morphology before and after surgery. In a statistical study on endothelial cell morphology, cell parameters except for minimal cell area correlated significantly with age. Although the density and size of dark areas correlated with each other, neither correlated with any of the cell parameters. CONCLUSION Cornea guttata does not lead to visual impairment or abnormalities in corneal endothelial cell parameters except for a small number of cases that must be considered to be at an early stage of Fuchs dystrophy.
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Affiliation(s)
- K Kitagawa
- Department of Ophthalmology, Kanazawa Medical University, Uchinada, Ishikawa, Japan
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48
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Takano T, Schulte-Eistrup S, Yoshikawa M, Nakata K, Kawahito S, Maeda T, Nonaka K, Linneweber J, Glueck J, Fujisawa A, Makinouchi K, Yokokawa M, Nosé Y. Impeller design for a miniaturized centrifugal blood pump. Artif Organs 2000; 24:821-5. [PMID: 11091172 DOI: 10.1046/j.1525-1594.2000.06630.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The impeller design for a miniature centrifugal blood pump is an important consideration since the small diameter impeller requires higher rotational speed, which may cause more blood trauma compared to the larger diameter impeller. Three different impeller vanes (straight vanes with a height of 4 mm and 8 mm, and 8 mm curved vanes) of which the diameter was 35 mm were subjected to hydraulic performance and hemolysis tests in the same pump housing. Both straight vane impellers attained left ventricular assist condition (5 L/min against 100 mm Hg) at 2,900 rpm while the curved vane required 3,280 rpm. There was no significant hemolysis difference between the tall and short vanes. The curved impeller vanes did not exhibit sufficient hydraulic performance when compared to the straight vanes. The straight vane impellers, even with different heights, were incorporated into the same pump housings, and the vane heights did not drastically change the hydraulic performance or hemolysis.
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Affiliation(s)
- T Takano
- Baylor College of Medicine, Department of Surgery, Houston, Texas 77030, USA.
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49
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Nakata K, Yoshikawa M, Takano T, Maeda T, Nonaka K, Linneweber J, Kawahito S, Glueck J, Fujisawa A, Makinouchi K, Yokokawa M, Nosé Y. Gyro pump wear and deformation analysis in vivo study: creep deformation. Artif Organs 2000; 24:653-5. [PMID: 10971256 DOI: 10.1046/j.1525-1594.2000.06596.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The Gyro pump has a double pivot bearing system to support its impeller. In this study, the integrity of the bearing system was examined after ex vivo studies. The pumps were implanted into calves and evaluated for different periods as a paracorporeal left ventricular assist device (LVAD). One pump was subjected to a test of 30 days, 1 for 15 days, 4 for 14 days, 1 for 10 days, 1 for 7 days, 2 for 4 days, and 4 for 2 days. One additional pump was subjected to percutaneous cardiopulmonary support (PCPS) condition for 6 days (total pressure head 500 mm Hg with a pump flow rate of 3 L/min). The anticoagulation treatment consisted of a continuous administration of heparin to maintain an achieved clotting time (ACT) of 200-250 s during the LVAD study and 250-300 s during the PCPS study. After the experiment, the pumps were disassembled, and the wear and deformation of male and female bearings were analyzed. There were no dimensional changes on male bearings but there were on female bearings. Wear and deformation of the female bearings were calculated as follows: wear and deformation = (depth of female before pumping) - (depth after pumping). Thirteen assembled Gyro pumps were disassembled to measure the depth of the female bearings before pumping. There was no statistical relationship between the wear and deformation and the motor speed x driving period. From these results, the deformation was not due to wear but to the creep or elastic deformation. This study suggested that the double pivot bearing system of the Gyro pump is highly durable.
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Affiliation(s)
- K Nakata
- Department of Surgery, Baylor College of Medicine, Houston, Texas, USA
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50
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Nakata KI, Yoshikawa M, Takano T, Sankai Y, Ohtsuka G, Glueck J, Fujisawa A, Makinouchi K, Yokokawa M, Nosaka S, Nose Y. Control system for an implantable rotary blood pump. Ann Thorac Cardiovasc Surg 2000; 6:242-6. [PMID: 11042480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
Rotary blood pumps can be used for long-term left ventricular assist devices. These pumps have several advantages over the conventional pulsatile pumps including smaller size, higher efficiency, and simple design and construction. However, one of the difficulties associated with the rotary blood pump is the proper control method to maintain an optimum flow rate in different physiological conditions. The rotary blood pump can be controlled by two methods. The first is to utilize the measured pump flow rate from its servo signal. The second is to detect and avoid abnormal pumping conditions such as; back flow and sudden increase in the pressure head. This abnormal situation typically occurs from excessive suction of blood when there is a functional or mechanical occlusion in the inflow cannula. The ultrasound flow meter is durable and reliable but it is difficult to continually monitor the blood flow rate of an implantable pump. Therefore, another method is needed instead of the continuous flow monitoring. One chronic calf having an LVAD was subjected for the development of this control system. This calf survived more than 6 months. Voltage, current, motor speed, heart rate and the pump flow rate were recorded and stored at 30-min intervals in a computer. Utilizing these parameters, attempts were made (1) to achieve indirect flow assessments and (2) to reveal abnormal operating parameters of the centrifugal pump (1). Indirect flow measurement, the predicted pump flow rate was calculated from these pump derived parameters (required power, motor speed and heart rate). The value of the coefficient of determination (R) between the measured and estimated pump flow rate was 0.796. (2) Abnormal operating indicator, there was an association between the required current and pump flow waves. The current was differentiated, and then calculated to the power of the differentiated current. The normal range of this value was 0.02+/-0.54. In abnormal conditions, this abnormal operating indicator increased 500 times. The predicted flow estimation method and abnormal operating indicator were available from intrinsic operating parameters of the pump and need no sensors. These two methods were simple, yet they are possibly effective and reliable servo control methods for a rotary blood pump.
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Affiliation(s)
- K I Nakata
- Department of Surgery, Baylor College of Medicine, One Baylor Plaza, Houston, Texas 77030, USA
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