617 results on '"Kusama, Y."'
Search Results
202. 876 Human urotensin II activates the sarcolemmal Na+/H+ exchanger: roles of protein kinase C and mitogen-activated protein kinase(s)
- Author
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Kato, K., Yasutake, M., Jia, D., Kusama, Y., and Takano, T.
- Subjects
PROTEIN kinase C ,MITOGEN-activated protein kinases - Abstract
An abstract of the study "Human urotensin II activates the sarcolemmal Na+/H+ exchanger: roles of protein kinase C and mitogen-activated protein kinase(s)," by K. Kato et al. is presented.
- Published
- 2004
203. Characteristics of the JT-60 divertor and limiter plasmas with high power auxiliary heating
- Author
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The JT-60 Team, Aikawa, H, Akaoka, N, Akasaka, H, Akino, N, Akiyama, T, Ando, T, Annoh, K, Aoyagi, T, Arai, T, Arakawa, K, Araki, M, Azumi, M, Chiba, S, Dairaku, M, Ebisawa, N, Fujii, T, Fukuda, T, Funahashi, A, Furukawa, H, Hamamatsu, K, Hanada, M, Hara, M, Haraguchi, K, Hiratsuka, H, Hirayama, T, Hiroki, S, Hiruta, K, Honda, M, Horiike, H, Hosoda, R, Hosogane, N, Iijima, T, Ikeda, K, Ikeda, Y, Imai, T, Inoue, T, Isaji, N, Isaka, M, Ishida, S, Itami, K, Ichige, N, Itoh, T, Kakizaki, T, Kaminaga, A, Katoh, T, Kawai, M, Kawabe, M, Kawamata, Y, Kawasaki, K, Kikuchi, K, Kikuchi, M, Kimura, H, Kimura, T, Kishimoto, H, Kitamura, S, Kitsunezaki, A, Kiyono, K, Kobayashi, N, Kodama, K, Koide, S, Koide, Y, Koike, T, Komata, M, Kondo, I, Konoshima, S, Kubo, H, Kunieda, S, Kurihara, K, Kuriyama, M, Kuroda, T, Kusaka, M, Kusama, Y, Mabuchi, Y, Maehara, S, Maeno, K, Matoba, T, Matsuda, S, Matsukawa, M, Matsukawa, T, Matsuoka, M, Miura, Y, Miya, N, Miyachi, K, Miyo, Y, Mizuno, M, Mori, M, Moriyama, S, Mutoh, M, Nagami, M, Nagashima, A, Nagashima, K, Nagashima, T, Nagaya, S, Naito, O, Nakamura, H, Nakamura, Y, Nemoto, M, Neyatani, Y, Ninomiya, H, Nishino, N, Nishitani, T, Obara, K, Obinata, H, Ogawa, Y, Ogiwara, N, Ohga, T, Ohara, Y, Ohasa, K, Ohara, H, Ohshima, T, Ohkubo, M, Ohsawa, S, Ohta, K, Ohta, M, Ohtaka, M, Ohuchi, Y, Oikawa, A, Okumura, H, Okumura, Y, Omori, K, Omori, S, Omori, Y, Ozeki, T, Saegusa, M, Saitoh, N, Sakamoto, K, Sakasai, A, Sakata, S, Sasajima, T, Satou, K, Satou, M, Sakurai, A, Sawahata, M, Sebata, T, Seimiya, M, Seki, M, Seki, S, Shibanuma, K, Shimada, R, Shimada, T, Shimizu, K, Shimizu, M, Shimomura, Y, Shinozaki, S, Shirai, H, Shirakata, H, Shitomi, M, Suganuma, K, Sugie, T, Sugiyama, T, Sunaoshi, H, Suzuki, K, Suzuki, M, Suzuki, N, Suzuki, S, Suzuki, Y, Takahashi, M, Takahashi, S, Takahashi, T, Takasaki, M, Takatsu, H, Takeuchi, H, Takeshita, A, Takizuka, T, Tamura, S, Tanaka, S, Tani, K, Terakado, M, Terakado, T, Tobita, K, Tokutake, T, Totsuka, T, Toyoshima, N, Tsuda, F, Tsugita, T, Tsuji, S, Tsukahara, Y, Tsuneoka, M, Uehara, K, Umehara, M, Uramoto, Y, Usami, H, Ushigusa, K, Usui, K, Yagyu, J, Yamagiwa, M, Yamamoto, M, Yamamoto, T, Yamashita, O, Yamazaki, T, Yasukawa, T, Yokokura, K, Yokomizo, H, Yokoyama, K, Yoshikawa, K, Yoshikawa, M, Yoshida, H, Yoshino, R, Yoshioka, Y, Yonekawa, I, Yoneda, T, Watanabe, K, Bell, M.G, Bickerton, R.J, Engelhardt, W, Goldston, R.J, Ilne, E.K, Kaline, J, Kugel, H.W, Mondino, P.L, Soldner, F.X, Takase, Y, Thomas, P.R, and Wong, K.L
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- 1989
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204. Experimental study on beam acceleration with combined NBI heating and second-harmonic ICRF heating in JT-60.
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Kimura, H., Fujii, T., Tobita, K., Yamagiwa, M., Hamamatsu, K., Saigusa, M., Azumi, M., Hosogane, N., Kobayashi, N., Kusama, Y., Mizuno, M., Nagashima, T., Nemoto, M., Ninomiya, H., Takeuchi, H., Takizuka, T., Yoshino, R., and Team, JT-60
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- 1991
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205. Heating and confinement characteristics of second hearmonic heating in the ion cyclotron range of frequencies on the JT-60 tokamak.
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Fujii, T., Kimura, H., Saigusa, M., Moriyama, S., Hamamatsu, K., Annoh, K., Fukuda, T., Ishida, S., Kobayashi, N., Koide, Y., Kubo, H., Kusama, Y., Nagashima, K., Nemoto, M., Nishitani, T., Ogawa, Y., Sakasai, A., Sato, M., Shinozaki, S., and Sugie, T.
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- 1991
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206. Enhancement of energy confinement by acceleration of fast ions in combined lower hybrid and neutral beam heating on JT-60.
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Imai, T., Ushigusa, K., Ikeda, Y., Nemoto, N., Kusama, Y., Matsuoka, M., and Team, JT-60
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- 1990
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207. High ion temperatures and transport characteristics of high Zeff hydrogen plasmas in JT-60 limiter discharges.
- Author
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Hosogane, N., Shimizu, K., Shirai, H., Kusama, Y., Tobita, K., Nemoto, M., Sakasai, A., Koide, Y., Nagashima, K., Yoshida, H., and Team, JT-60
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- 1988
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208. ChemInform Abstract: Synthesis and Antitumor Activity of Novel Cyclopropapyrroloindole (CPI) Derivatives Bearing Methoxycarbonyl and Trifluoromethyl Groups.
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FUKUDA, Y., FURUTA, H., SHIGA, F., OOMORI, Y., KUSAMA, Y., EBISU, H., and TERASHIMA, S.
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- 1997
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209. ChemInform Abstract: Synthesis and Antitumor Activity of Novel Cyclopropapyrroloindole (CPI) Derivatives Bearing Bis(methoxycarbonyl) Groups.
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FUKUDA, Y., OOMORI, Y., KUSAMA, Y., and TERASHIMA, S.
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- 1997
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210. Highly accurate approximate solutions of the Stokes equation for high electron density and long laser wavelength.
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Imazawa, R., Kawano, Y., and Kusama, Y.
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STOKES equations , *ELECTRON distribution , *LASER beams , *WAVELENGTHS , *APPROXIMATION theory , *PARAMETER estimation , *POLARIZATION (Nuclear physics) - Abstract
We have transformed the Stokes equation to equations written in the polarization ellipse parameters. Since the transformed Stokes equations directly describe change in each polarization ellipse parameter, they enable us to easily and comprehensively understand change in the polarization ellipse in a plasma. We have obtained highly accurate approximate solutions of the transformed Stokes equation in order to connect the measured polarization state to the plasma parameters (the electron density and the magnetic field) in a short CPU time. We have compared our solutions and the other approximate solutions proposed by previous studies. Only our solutions have shown good agreement between the polarization parameters and the line-integrated plasma parameters. The errors of our solutions are less than 2% of the domain of each polarization parameter up to the high electron density (∼7 × 1020 m-3) and the long laser wavelength (∼170 &mgr;m). The CPU time of our solutions is 10 times shorter than that of the Stokes equation. [ABSTRACT FROM AUTHOR]
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- 2012
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211. Exposure of reduced activation ferritic steel F82H to TEXTOR plasma
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Tsuzuki, K., Hirai, T., Kusama, Y., Phillips, V., Pospiesczck, A., Sakamoto, M., Sakawa, Y., Sergienko, G, Schweer, B., Tanabe, T., and Ueda, Y.
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FERRITIC steel , *CORROSION & anti-corrosives , *FUSION reactors , *HEAT flux - Abstract
Abstract: Reduced activation ferritic steel, which is a leading structural material candidate for a fusion demonstration reactor, has been installed in TEXTOR and exposed to neutral beam heated plasma. When the heat load was lower than 5MW/m2, the insertion of the test limiter did not influence the plasma parameters. Visible spectroscopy near the surface showed that the emission related to constituent element such as iron and chromium is comparable to that from the stainless steel. It means that the sputtering from the ferritic steel is comparable to that from the stainless steel even for plasma exposure in high heat flux condition. When the heat load was ∼10MW/m2, the limiter was melted slightly. The strange motion of melted layer was observed by 2D camera. It slowly moved (∼0.5cm/s) in a spiral motion, forming a small droplet ∼1mm in diameter which was then released. The released droplet turned toward the limiter and hit the surface. The mechanism of this motion is discussed. [Copyright &y& Elsevier]
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- 2006
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212. Formation of a Charge-Exchange Target for Fast Ions in the Plasma of Large-Scale Toroidal Devices under NBI Conditions.
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Mironov, M. I., Khudoleev, A. V., and Kusama, Y.
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HYDROGEN isotopes , *IONS , *TOKAMAKS , *PINCH effect (Physics) , *FUSION reactors , *TRAPPED-particle instabilities , *PLASMA gases , *PHYSICS - Abstract
High-energy (E > 0.2 MeV) charge-exchange diagnostics allow the determination of the distribution function of fast atoms produced via the neutralization of hydrogen isotope ions by target hydrogen-like impurity ions. To derive the distribution function from the experimental data requires knowledge of the composition and spatial distribution of the target ions in a tokamak plasma. A charge-exchange target forms as a result of the interaction between the main impurity nuclei and the heating neutral beams. In different devices, the heating beams are arranged in different ways with respect to the diagnostics; hence, in order to accurately estimate the contribution of the secondary ions to the detected signal, it is necessary to calculate their trajectories for every particular case. A model is proposed that takes into account elementary processes resulting in the ionization equilibrium of the ions of different impurities with allowance for ion motion in a specific tokamak configuration. As an example, the model is applied to the plasma of the JT-60U tokamak. Mechanisms for the formation of charge-exchange atomic flows in various energy ranges are considered. The relative contributions of different heating injectors to the charge-exchange flow are estimated. Based on the calculated results, a method is proposed for local measurements of the ion distribution function with the help of a stationary analyzer. © 2004 MAIK “Nauka / Interperiodica”. [ABSTRACT FROM AUTHOR]
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- 2004
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213. In situ spectral calibration method for the impurity influx monitor (divertor) for ITER using angled physical contact fibers
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Kusama, Y [Fusion Research and Development Directorate, Japan Atomic Energy Agency, Ibaraki 311-0193 (Japan)]
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- 2011
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214. Defining the infrared systems for ITER
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Kusama, Y [JAEA, Naka-shi, Ibaraki 311-0193 (Japan)]
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- 2010
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215. Linearity-independent method for a safety factor profile.
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Imazawa, R., Kawano, Y., Itami, K., and Kusama, Y.
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CONSTRAINT satisfaction , *LINEAR statistical models , *DATA analysis , *MAGNETIC fields , *EQUILIBRIUM , *ARC length - Abstract
This paper proposes a new method to calculate a safety factor, q, profile from gridded data of a poloidal flux, Ψ, efficiently and accurately. Difficulties of calculating q are derived from a difficulty of specifying a contour line of Ψ and a singularity at a magnetic axis. In order to solve the first difficulty, the proposed method interpolates knots, which are located on a target Ψ, by utilizing a normalized arc length and constraints expressed by a magnetic field. Regarding the second difficulty, the proposed method identifies q0 by extrapolating a q profile around a magnetic axis with a constraint of dq/dρ = 0 at the magnetic axis. Accuracy assessments of the proposed method are carried out by utilizing the Solov'ev-type equilibrium. The results show the validity and high performance of the proposed method. [ABSTRACT FROM AUTHOR]
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- 2014
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216. Does subjective evaluation of the frequency of salty food intake predict the risk of incident hypertension? A 4-year follow-up study in a middle-aged population.
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Otsuka, T., Kato, K., Ibuki, C., Kodani, E., Kusama, Y., and Kawada, T.
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HYPERTENSION risk factors , *BLOOD pressure , *CHI-squared test , *CONFIDENCE intervals , *DIET , *SALT , *STATISTICS , *PREDICTIVE tests , *PROPORTIONAL hazards models , *DATA analysis software , *DESCRIPTIVE statistics , *KAPLAN-Meier estimator - Abstract
Background Excess salt intake increases blood pressure ( BP). Identifying individuals with excess salt intake is, therefore, important for the prevention of hypertension. Aim To examine the predictive value of subjective evaluation of salty foods intake for the risk of incident hypertension in a middle-aged population. Methods A total of 970 non-hypertensive workers (mean age, 44 ± 6 years) was followed for a maximum period of 4 years, and their BP was measured annually. At baseline, all participants were asked about their subjective frequency of salty foods intake (seldom, sometimes or always), and they were divided into three groups according to their answers. Hypertension was defined as systolic/diastolic BP ≥ 140/90 mmHg or use of antihypertensive medications. Results There were no significant differences in the 4-year cumulative incident rate of hypertension among the 'seldom', 'sometimes' and 'always' groups (15.8%, 14.3% and 10.3%, respectively, log-rank test P = 0.44). In a multivariate Cox proportional hazards model, age, body mass index and the baseline BP category were independent predictors for developing hypertension, whereas the frequency of salty foods intake was not a predictor (adjusted hazard ratio (95% confidence interval), 0.99 (0.64-1.54) in the 'sometimes' group and 0.64 (0.33-1.28) in the 'always' group as compared with the 'seldom' group). Conclusion The subjective evaluation of salty foods intake did not predict the 4-year risk of incident hypertension in this study population. Further investigations with a longer follow-up period are needed to clarify whether the present insignificant results are maintained for more than 4 years. [ABSTRACT FROM AUTHOR]
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- 2013
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217. Process and overview of diagnostics integration in ITER ports.
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Drevon, J.M., Walsh, M., Andrew, P., Barnsley, R., Bertalot, L., de Bock, M., Bora, D., Bouhamou, R., Direz, M.F., Encheva, A., Fang, T., Feder, R., Giacomin, T., von Hellermann, M., Jakhar, S., Johnson, D., Kaschuk, Y., Kusama, Y., Lee, H.G., and Levesy, B.
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PARTICLE beam diagnostics , *COMPUTER input-output equipment , *ENGINEERING design , *MANUFACTURING processes - Abstract
Abstract: ITER will have a set of 45 diagnostics to ensure controlled operation. Many of them are integrated in the ITER ports. This paper addresses the integration process of the diagnostic systems and the approach taken to enable coordinated progress. An overview of the Port Integration hardware introduces the various structures needed for hosting tenant systems inside ITER diagnostics ports. The responsibilities of the different parties involved (ITER Organization and the Domestic Agencies) are outlined. The main challenges for diagnostic port integration engineering are summarized. The plan for a common approach to design and manufacture of the supporting structures, in particular the Port Plug is detailed. A coordinated design including common components and a common approach for neutronic analyses is proposed. One particular port, the equatorial port 11, is used to illustrate the approach. [Copyright &y& Elsevier]
- Published
- 2013
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218. Designing a prototype of the ITER pulse scheduling system
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Yamamoto, T., Yonekawa, I., Ohta, K., Hosoyama, H., Hashimoto, Y., Wallander, A., Winter, A., Sugie, T., Kusama, Y., Kawano, Y., and Yoshino, R.
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COMPUTER scheduling , *PROTOTYPES , *PLASMA gases , *PARAMETER estimation , *COMPUTER simulation - Abstract
Abstract: A prototype of the ITER pulse scheduling system that prepares and manages parameters for ITER plasma operations has been designed. Based on the analyzed requirements on the system, structure of the parameters and necessary functions were determined. Segment and module structures were tuned to the ITER requirements. Three types of validations assure sanity of the parameters. The design limits check and the operation window check verify whether the values of the parameters do not exceed the limits. The consistency check calculates dependency among parameters in accordance with logics described in a scripting language. The ITER pulse scheduling system provides interface with a physics model and simulator. Some abstract physics parameters are converted to engineering parameters with the physics simulation. The results of simulation such as plasma characteristics of specified parameters are also shown to the researchers. The tool to specify the parameters is data-driven. Therefore, it is flexible for changes of number of the parameters. A prototype is being implemented in 2011. Using the prototype, this design will be verified and refined. The evaluation of the prototype will be a basis of the final production of the ITER pulse scheduling system. [Copyright &y& Elsevier]
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- 2012
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219. Simulation of VDE under intervention of vertical stability control and vertical electromagnetic force on the ITER vacuum vessel
- Author
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Miyamoto, S., Sugihara, M., Shinya, K., Nakamura, Y., Toshimitsu, S., Lukash, V.E., Khayrutdinov, R.R., Sugie, T., Kusama, Y., and Yoshino, R.
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STABILITY theory , *ELECTROMAGNETISM , *MAGNETIC fields , *SYSTEMS design , *PLASMA gases , *SIMULATION methods & models - Abstract
Abstract: Vertical displacement events (VDEs) and disruptions usually take place under intervention of vertical stability (VS) control and the vertical electromagnetic force induced on vacuum vessels is potentially influenced. This paper presents assessment of the force that arises from the VS control in ITER VDEs using a numerical simulation code DINA. The focus is on a possible malfunctioning of the ex-vessel VS control circuit: radial magnetic field is unintentionally applied to the direction of enhancing the vertical displacement further. Since this type of failure usually causes the largest forces (or halo currents) observed in the present experiments, this situation must be properly accommodated in the design of the ITER vacuum vessel. DINA analysis shows that although the ex-vessel VS control modifies radial field, it does not affect plasma motion and current quench behavior including halo current generation because the vacuum vessel shields the field created by the ex-vessel coils. Nevertheless, the VS control modifies the force on the vessel by directly acting on the eddy current carried by the conducting structures of the vessel. Although the worst case was explored in a range of plasma inductance and pattern of VS control in combination with the in-vessel VS control circuit, the result confirmed that the force is still within the design margin. [Copyright &y& Elsevier]
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- 2012
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220. Neutronic analysis of the ITER poloidal polarimeter
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Ishikawa, M., Kawano, Y., Imazawa, R., Sato, S., Vayakis, G., Bertalot, L., Yatsuka, E., Hatae, T., Kondoh, T., and Kusama, Y.
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FUSION reactors , *POLARISCOPE , *ELECTRIC heating , *MIRRORS , *INSTALLATION of equipment , *PLASMA gases , *RADIATION shielding , *GAMMA rays - Abstract
Abstract: The nuclear heating rates of the optical mirrors of the poloidal polarimeter installed in the equatorial port plug of ITER are calculated. Since the system cannot have a sufficiently labyrinthine structure and the second mirrors are located closer to the plasma than the first mirrors due to limited space, the nuclear heating rate of the second mirrors is as high as that of the first mirrors. However, it is possible to reduce the nuclear heating rates more than 1 order if the blanket shield module provides a sufficient degree of neutron shielding. The effect of the neutron shield on the peripheral region of the upper port plug, in which the optical system of the poloidal polarimeter is installed, is also evaluated. The gamma-ray dose rate 106 s after shutdown of operations in the back flange region has been estimated to be ∼60μSv/h when the neutron shield is filled in the port plug, which is below the design threshold for the ITER maintenance phase. Further, the nuclear heating rate of the Poloidal field coil near the same upper port has been evaluated to be more than 2 orders lower than the allowable value of 1mW/cc. [Copyright &y& Elsevier]
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- 2011
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221. Electromagnetic studies of the ITER generic upper port plug
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Sato, K., Yaguchi, E., Pitcher, C.S., Walker, C., Encheva, A., Kawano, Y., and Kusama, Y.
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ELECTROMAGNETISM , *FUSION reactors , *STRUCTURAL analysis (Engineering) , *STRAINS & stresses (Mechanics) , *PLASMA diagnostics , *NUCLEAR engineering - Abstract
Abstract: Electromagnetic analysis of the ITER generic upper port plug was carried out to estimate the most severe load to which the in-vessel components would be subjected. Static and dynamic analyses based on expected EM loads were also performed to evaluate the structural behavior of the generic upper port plug. These analyses reveal that stress and displacement of the upper port plug structure exceed design guidelines when the structure is subjected to an upward fast VDE. Stiffening the upper port plug will decrease stress and the severity of potential displacement. The design of the middle part of the generic upper port plug was considered. Static and dynamic analyses for stress and displacement of the port plug indicate that the stiffened model satisfies structural design guidelines. Further improvements have been considered to achieve sufficient design margins for the generic upper port plug for ITER. A deep slit in the diagnostic first wall and the diagnostic shield module was designed to mitigate the EM load. Additional EM analysis confirmed the applicability of these proposals. Results confirm that the generic upper port plug structure is able to withstand plasma disruptions. [Copyright &y& Elsevier]
- Published
- 2011
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222. In situ spectral calibration method for the impurity influx monitor (divertor) for ITER using angled physical contact fibers.
- Author
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Iwamae, A., Ogawa, H., Sugie, T., and Kusama, Y.
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SPECTRAL reflectance , *CALIBRATION , *CASSEGRAINIAN telescopes , *FIBERS , *IMPURITY distribution in semiconductors , *SIGNAL-to-noise ratio , *WAVELENGTHS - Abstract
The in situ calibration method for the impurity influx monitor (divertor) is experimentally examined. The total reflectance of the optical path from the focal point of the Cassegrain telescope to the first mirror is derived using a micro retroreflector array. An optical fiber with angled physical contact (APC) connectors reduces the return edge reflection. APC fibers and a multimode coupler increase the signal-to-noise ratio by about one order compared to that of triple-branched fibers and enable measurement of the wavelength dependence of the total reflectance of the optical system even after potential deterioration of mirror surfaces reduces reflectance. [ABSTRACT FROM AUTHOR]
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- 2011
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223. Terrace retro-reflector array for poloidal polarimeter on ITER.
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Imazawa, R., Kawano, Y., Ono, T., and Kusama, Y.
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POLARISCOPE , *REFLECTING telescopes , *LASERS , *ANGLE of attack (Aerodynamics) , *DIFFRACTION gratings , *DIFFRACTION patterns , *SIMULATION methods & models , *POLARIMETRY - Abstract
A new concept of a terrace retro-reflector array (TERRA) as part of the poloidal polarimeter for ITER is proposed in this paper. TERRA reflects a laser light even from a high incident angle in the direction of the incident-light path, while a conventional retro-reflector array cannot. Besides, TERRA can be installed in a smaller space than a corner-cube retro-reflector. In an optical sense, TERRA is equivalent to a Littrow grating, the blaze angle of which varies, depending on the incident angle. The reflected light generates a bright and dark fringe, and the bright fringe is required to travel along the incident-light path to achieve the objects of laser-aided diagnostics. In order to investigate the propagation properties of laser light reflected by TERRA, we have developed a new diffraction formula. Conditions for the propagation of the bright fringe in the direction of the incident light have been obtained using the Littrow grating model and have been confirmed in a simulation applying the new diffraction formula. Finally, we have designed laser transmission optics using TERRA for the ITER poloidal polarimeter and have calculated the light propagation of the system. The optical design obtains a high transmission efficiency, with 88.6% of the incident power returned. These results demonstrate the feasibility of applying TERRA to the ITER poloidal polarimeter. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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224. Defining the infrared systems for ITER.
- Author
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Reichle, R., Andrew, P., Counsell, G., Drevon, J.-M., Encheva, A., Janeschitz, G., Johnson, D., Kusama, Y., Levesy, B., Martin, A., Pitcher, C. S., Pitts, R., Thomas, D., Vayakis, G., and Walsh, M.
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FUSION reactors , *INFRARED radiation , *THERMOGRAPHY , *OPTICAL resolution , *OPTICAL reflection , *CALIBRATION , *BREMSSTRAHLUNG - Abstract
The International Thermonuclear Experimental Reactor will have wide angle viewing systems and a divertor thermography diagnostic, which shall provide infrared coverage of the divertor and large parts of the first wall surfaces with spatial and temporal resolution adequate for operational purposes and higher resolved details of the divertor and other areas for physics investigations. We propose specifications for each system such that they jointly respond to the requirements. Risk analysis driven priorities for future work concern mirror degradation, interfaces with other diagnostics, radiation damage to refractive optics, reflections, and the development of calibration and measurement methods for varying optical and thermal target properties. [ABSTRACT FROM AUTHOR]
- Published
- 2010
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225. Conceptual design of the collection optics for the edge Thomson scattering system in ITER.
- Author
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Yatsuka, E., Hatae, T., Suitoh, S., Aida, Y., and Kusama, Y.
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NUCLEAR reactor design & construction , *FUSION reactors , *THOMSON scattering , *IRRADIATION , *GAMMA rays , *NEUTRONS , *FIBER optics , *ELECTRON distribution , *OPTICAL resolution , *RAMAN effect - Abstract
Neutron and gamma-ray irradiation complicates the design of the edge Thomson scattering (TS) system in ITER. The TS light is relayed through the relaying optics with labyrinth and fiber coupling optics. Electron density of 2×1019 m-3 is sufficient to measure Te and ne within a 10% and 5% margin of error, respectively, with a spatial resolution of 5 mm. This system can cover from 0.85 to 1 of the normalized minor radius. The time resolution is 10 ms, which is determined by the repetition rate of the laser device. A super-Gaussian is the ideal laser profile for the laser injection optics to avoid a breakdown of the filling gas used in density calibration through Raman scattering. [ABSTRACT FROM AUTHOR]
- Published
- 2010
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226. Relationship between job strain and radial arterial wave reflection in middle-aged male workers.
- Author
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Otsuka T, Kawada T, Ibuki C, and Kusama Y
- Abstract
OBJECTIVE: This study examined the relationship between job stain and radial arterial wave reflection as expressed by the augmentation index (AI), a marker of cardiovascular risk, in middle-aged male workers. METHODS: Radial AI was measured using automated applanation tonometry in 808 working men (mean age; 47+/-5 years) at a company in Kanagawa, Japan in 2007. An elevated AI represents the deterioration of arterial properties and increased cardiovascular risk. Job demand and job control (decision latitude) were evaluated by a self-administered, Brief Job Stress Questionnaire. High job strain was defined as the combination of high job demand and low job control. RESULTS: In the entire study population, the mean+/-SD and the median of AI were 74+/-13% and 75%, respectively. High job strain was seen in 267 subjects. In a multiple logistic regression analysis with adjustment for multiple potential confounders, high job strain showed a significantly increased odds ratio (1.47, 95% CI; 1.04-2.09, P=0.029) for an elevated AI (> or =75%). CONCLUSION: High job strain was significantly associated with an elevated radial AI. The measurement of AI may be useful when incorporated in workplace interventions to reduce the risk of cardiovascular disease, especially at sites where workers tend to perceive high job strain.Copyright © 2009 by Elsevier Inc. [ABSTRACT FROM AUTHOR]
- Published
- 2009
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227. Engineering design of the ITER invessel neutron monitor using micro-fission chambers
- Author
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Nishitani, T., Yamauchi, M., Izumi, M., Hayakawa, A., Ebisawa, K., Kondoh, T., and Kusama, Y.
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PARTICLES (Nuclear physics) , *PHYSICAL & theoretical chemistry , *ENGINEERING design , *ANALYTICAL chemistry - Abstract
Abstract: An invessel neutron monitor using micro-fission chambers is one of the most important diagnostics to measure the fusion power in ITER. A single micro-fission chamber with 10mg of 235U to be installed in a gap between a shielding blanket module and a vacuum vessel can cover the range of the fusion power from 100kW to 1GW. For the low fusion power operation including D–D operation, a micro-fission chamber bundle consisting of 13 micro-fission chamber units has been designed. Nuclear heating of the micro-fission chamber for high power operations and the micro-fission chamber bundle for low power operation were analyzed by neutron transport calculations using the MCNPX code. Heat transport analyzes for the micro-fission chambers were carried out with a general purpose Finite Element Method code ANSYS 8.1, which indicated that the detector temperature might be kept less than the operational temperature limit by the thermal conduction to the vacuum vessel with the heat transfer coefficient of 100W/m2 K or larger. [Copyright &y& Elsevier]
- Published
- 2007
- Full Text
- View/download PDF
228. Compact toroid injection system for JFT-2M
- Author
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Fukumoto, N., Ogawa, H., Nagata, M., Uyama, T., Shibata, T., Kashiwa, Y., Suzuki, S., and Kusama, Y.
- Subjects
- *
POWER resources , *ELECTRONICS , *PLASMA diagnostics , *TOROIDAL magnetic circuits - Abstract
Abstract: The compact toroid (CT) injection system for JFT-2M is composed of a CT injector, a gas delivery and vacuum system, a power supply system, and a diagnostics system. In particular, the power supply system delivers high performance for CT formation and acceleration. The CT formation capacitor bank unit achieved a formation current of 350kA with a rise time less than 10μs. Although the CT acceleration bank units are equipped with 14 ignitron switches instead of gap switches to attenuate the discharge noise level, an acceleration current of 400kA with a short rise time of 9μs is controlled within a jitter of much less than 1μs. The resulting CT velocity and mass density satisfy the requirements for CT penetration into the tokamak plasma core at a toroidal field of 1 T. This CT injection system is thus suitable for CT injection in a middle-sized tokamak plasma such as the JFT-2M tokamak. [Copyright &y& Elsevier]
- Published
- 2006
- Full Text
- View/download PDF
229. Convergence study of bispectral analysis in experiments of high temperature plasmas.
- Author
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Nagashima, Y., Itoh, S.-I., Yagi, M., Itoh, K., Fujisawa, A., Hoshino, K., Shinohara, K., Uehara, K., Kusama, Y., Ejiri, A., and Takase, Y.
- Subjects
- *
RESEARCH , *PLASMA confinement , *TURBULENCE , *STOCHASTIC convergence , *DRIFT waves , *MAGNETICS - Abstract
A convergence study of bispectral analysis on toroidal plasma turbulence is presented with a theoretical estimate of bicoherence for the system of the drift wave and zonal flow. Examples are chosen from the analysis of floating potential fluctuation in the edge region of the JFT-2M tokamak. The convergence properties of the bispectral functions are clarified for an oscillatory branch of zonal flow (or geodesic acoustic mode) and drift waves. The total squared bicoherence or the biphase converges inversely proportional to the realization number or to the square root of the realization number, respectively. The numbers of realizations to qualitatively converge and obtain a quantitatively significant value of bicoherence are discussed for the drift wave fluctuations and for the zonal flow. [ABSTRACT FROM AUTHOR]
- Published
- 2006
- Full Text
- View/download PDF
230. Blanket–plasma interaction in tokamaks: Implication from JT-60U, JFT-2M and reactor studies
- Author
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Kikuchi, M., Nishio, S., Kurita, G., Tsuzuki, K., Bakhtiari, M., Kawashima, H., Takenaga, H., Kusama, Y., and Tobita, K.
- Subjects
- *
PLASMA stability , *ELECTROMAGNETIC compatibility , *TOKAMAKS , *FERRITIC steel - Abstract
Abstract: Optimization of blanket–plasma interaction is one of important subjects of tokamak reactor design. This paper summarizes key physics R&D results of blanket–plasma interactions in tokamak system based on JT-60U, JFT-2M and DEMO studies at JAERI. Conflicting requirement between wall stabilization and disruption tolerance with respect to the electromagnetic coupling between plasma-structure seems to have a solution with somewhat distant wall location while minimization of the distance between plasma and stabilizing wall is critically important for high beta operation. Effect of ferromagnetism on plasma stability is well studied in JFT-2M and theoretically giving positive prospect for use of reduced activation ferritic steel as a first wall material. Enhancement of ion/neutral 1st wall interaction with 2nd SOL and saturated wall is discussed as an important R&D element for DEMO and existence of high-energy neutrals in JT-60U was mentioned. [Copyright &y& Elsevier]
- Published
- 2006
- Full Text
- View/download PDF
231. Deuterium retention of low activation ferritic steel and boronized wall in JFT-2M
- Author
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Yamauchi, Y., Yamaguchi, K., Hirohata, Y., Hashiba, M., Hino, T., Tsuzuki, K., and Kusama, Y.
- Subjects
- *
ENGINEERING , *FERRITIC steel , *DEUTERIUM , *BORON - Abstract
Abstract: Deuterium retention and erosion of F82H exposed to JFT-2M plasmas and the effect of boronization on the deuterium retention were examined based on material probe analysis. The amount of retained deuterium almost saturated after 300 tokamak discharges of deuterium. The retention of helium was clearly observed after helium glow discharge. The desorption temperature was approximately 600K. While no significant change in the surface atomic composition was observed after the exposure of tokamak discharges, the mixture layer of carbon, iron and oxygen was observed after the helium glow discharge due to surface erosion and redeposition of eroded particles. After the boronization using trimethylboron, both carbon and boron deposited at the surface. The atomic ratio of B to C was 1/3. The amount of retained deuterium significantly increased, three times larger than that before the boronization, owing to that a large amount of deuterium is trapped in the carbon content. [Copyright &y& Elsevier]
- Published
- 2006
- Full Text
- View/download PDF
232. Characteristics of modified CT injector for JFT-2M
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Fukumoto, N., Ogawa, H., Nagata, M., Uyama, T., Shibata, T., Kashiwa, Y., and Kusama, Y.
- Subjects
- *
CONSTITUTION of matter , *MAGNETIC structure , *CRYSTALLOGRAPHY , *CHEMICAL structure - Abstract
The HIT-CTI mark II compact toroid (CT) injector employed for the JFT-2M tokamak facility at the Japan Atomic Energy Research Institute (JAERI) has been upgraded to improve injection performance. The nozzle of the mark III injector now has a linear tube in place of the original focus cone to avoid rapid focus and deceleration, and the tapered outer electrode has been replaced with more gentle taper in the compression section in order to facilitate gradual compression. The dependence of CT velocity and electron density on poloidal bias flux and trigger time of CT acceleration have been investigated in the operable range of 70–230km/s average CT velocity and electron density of 0.1–1.0 × 1022m-3 at an accelerator bank voltage of 25kV. The operation window is broader than that of the mark II injector. Emission of a CT plasmoid from the injector, and transport to the flux conserver as a high-density spheromak magnetic structure have also been confirmed. [Copyright &y& Elsevier]
- Published
- 2004
- Full Text
- View/download PDF
233. Investigation of compatibility of low activation ferritic steel with high performance plasma by full covering of inside vacuum vessel wall on JFT-2M
- Author
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Tsuzuki, K., Shinohara, K., Kamiya, K., Kawashima, H., Sato, M., Kurita, G., Bakhtiari, M., Ogawa, H., Hoshino, K., Kasai, S., Uehara, K., Kusama, Y., Yamamoto, M., Shibata, T., Kikuchi, K., Tsutsui, H., Shimada, R., Hino, T., Hirohata, Y., and Amemiya, A.
- Subjects
- *
ACTIVATION (Chemistry) , *FERRITIC steel , *PLASMA gases , *VACUUM technology , *ENGINEERING design , *ELECTROMAGNETIC fields , *TOKAMAKS , *ELECTRIC discharges - Abstract
Low activation ferritic steel plates were installed in the JFT-2M tokamak to fully cover the inside wall of the vacuum vessel (ferritic inside wall; FIW) as a simulation of the blanket wall of the fusion demonstration reactor. After the physics and engineering design concerns with the ripple reduction, the electro-magnetic force and so on, FIW was installed with a tolerance of a few mm. The ripple reduction was confirmed from the detailed measurement. Tokamak discharges were obtained without changing control system, as predicted theoretically. The reduction of ripple loss of fast ions was clearly demonstrated by both experiments and calculations. Compatibility of FIW with high normalized beta plasma up to 3.3 was demonstrated at relatively far wall position. Preliminary investigation showed that the slowdown of the growth rate occurred with closer wall position, which presumably corresponds to wall stabilization effect. [Copyright &y& Elsevier]
- Published
- 2004
- Full Text
- View/download PDF
234. Impurity release and deuterium retention properties of a ferritic steel wall in JFT-2M
- Author
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Ogawa, H., Yamauchi, Y., Tsuzuki, K., Kawashima, H., Sato, M., Shinohara, K., Kamiya, K., Kasai, S., Kusama, Y., Yamaguchi, K., Hirohata, Y., Hashiba, M., and Hino, T.
- Subjects
- *
POINT defects , *DEUTERIUM , *FERRITIC steel , *NUCLEAR reactors , *NEUTRON irradiation , *PHYSICS laboratories , *STRUCTURAL plates - Abstract
Impurity release and the deuterium retention properties of the low activation ferritic steel, which is a candidate material for a demo-reactor, have been studied in the JFT-2M and in the laboratory. In the case when the inside vacuum vessel wall is fully covered by ferritic steel plates, enhancement of the oxygen influx and the emission of iron ion lines were not observed. This means that the impurity release from the ferritic steel has no deleterious effect on JFT-2M. From irradiation experiments, the retained amount of deuterium in the sample with an oxide layer was one order of magnitude larger than that of the mechanically polished sample for the low fluence case. However it became comparable at the high fluence case, and was roughly the same as that of SUS-316L. Retained amount of deuterium in the sample exposed to JFT-2M plasmas was similar to that exposed to the deuterium ion beam. [Copyright &y& Elsevier]
- Published
- 2004
- Full Text
- View/download PDF
235. Plasma material interaction studies on low activation materials used for plasma facing or blanket component
- Author
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Hino, T., Hirohata, Y., Yamauchi, Y., Hashiba, M., Kohyama, A., Katoh, Y., Lee, Y., Jinushi, T., Akiba, M., Nakamura, K., Yoshida, H., Sengoku, S., Tsuzuki, K., Kusama, Y., Yamaguchi, K., and Muroga, T.
- Subjects
- *
PLASMA gases , *ACTIVATION (Chemistry) , *SPUTTERING (Physics) , *STAINLESS steel , *VANADIUM alloys , *TITANIUM dioxide , *SURFACE coatings , *GAS absorption & adsorption , *PERMEABILITY - Abstract
Numerous issues on the plasma material interactions were investigated for low activation materials. Co-deposited carbon dust was prepared and the deuterium concentration was measured. The concentration was approximately half of the present design value for ITER. For ferritic steel, the deuterium retention was observed to be comparable to that of stainless steel. Physical sputtering yield was roughly the same as that for stainless steel. For the reduction of absorption rate in vanadium alloy, titanium oxide coating was conducted, and the coating was observed to be very effective for reduction of hydrogen absorption. Helium gas permeability was measured for numerous SiC/SiC composites, and the SiC/SiC composite made by the NITE process showed quite low permeability. The SiC/SiC blanket may be able to be used without helium leakage into plasma. [Copyright &y& Elsevier]
- Published
- 2004
- Full Text
- View/download PDF
236. Singlet oxygen-induced ultrastructural injury, calcium shifts and arrhythmias in the aerobic isolated perfused rat heart during the photosensitization of rose bengal
- Author
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Bernier, M, Vandeplassche, G, Kusama, Y, Borges, M, and Hearse, DJ
- Published
- 1988
- Full Text
- View/download PDF
237. Development of in-vessel components of the microfission chamber for ITER.
- Author
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Ishikawa, M., Kondoh, T., Ookawa, K., Fujita, K., Yamauchi, M., Hayakawa, A., Nishitani, T., and Kusama, Y.
- Subjects
- *
NUCLEAR fission , *CONTROLLED fusion , *NEUTRON sources , *VACUUM tubes , *INSULATING materials , *NUCLEAR fusion , *FUSION reactors , *NUCLEAR research - Abstract
Microfission chambers (MFCs) will measure the total neutron source strength in ITER. The MFCs will be installed behind blanket modules in the vacuum vessel (VV). Triaxial mineral insulated (MI) cables will carry signals from the MFCs. The joint connecting triaxial MI cables in the VV must be considered because the MFCs and the MI cables will be installed separately at different times. Vacuum tight triaxial connector of the MI cable has been designed and a prototype has been constructed. Performance tests indicate that the connector can be applied to the ITER environment. A small bending-radius test of the MI cable indicates no observed damage at a curvature radius of 100 mm. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
238. Engineering and maintenance studies of the ITER diagnostic upper port plug
- Author
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Sato, K., Ohmori, J., Kondoh, T., Hatae, T., Kajita, S., Ishikawa, M., Neyatani, Y., Ebisawa, K., and Kusama, Y.
- Subjects
- *
PLASMA diagnostics , *NUCLEAR reactor design & construction , *FUSION reactors , *MAINTENANCE , *ELECTROMAGNETIC fields , *ENGINEERING tolerances , *STRUCTURAL analysis (Engineering) , *FORCE & energy - Abstract
Abstract: Engineering analyses have been performed for the representative diagnostic upper port plug of ITER. Maintenance and integration design have been also carried out for the diagnostic components to be installed in the upper port plug. From the electromagnetic and structural analyses, it has come up an important problem to suppress the displacement of the upper port plug rather than to reduce the produced stress. Reducing the electro-magnetic (EM) force will help to decrease the severity of potential displacement. Maximum displacement of the port plug decreases with increase in the number of slits in a manner that the displacement would seem to be less than the design tolerance. A proposed low body roller and inner frame may enhance maintenance and integration. These studies and designs have established the design basis for the diagnostic upper port plug. [Copyright &y& Elsevier]
- Published
- 2009
- Full Text
- View/download PDF
239. Inter-code comparison benchmark between DINA and TSC for ITER disruption modelling.
- Author
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Miyamoto, S., Isayama, A., Bandyopadhyay, I., Jardin, S.C., Khayrutdinov, R.R., Lukash, V.E., Kusama, Y., and Sugihara, M.
- Subjects
- *
SIMULATION methods & models , *PLASMA instabilities , *TOKAMAKS , *PLASMA boundary layers - Abstract
Results of 2D disruption modelling for validation of benchmark ITER scenarios using two established codes—DINA and TSC, are compared. Although the simulation models employed in those two codes ought to be equivalent in the resistive time scale, quite different defining equations and formulations are adopted in their approaches. Moreover there are considerable differences in the implemented model of solid conducting structures placed on the periphery of the plasma such as the vacuum vessel and blanket modules. Thus it has long been unanswered whether the one of the two codes is really able to reproduce the other's results correctly, since a large number of code-wise differences render the comparison task exceedingly complicated. In this paper, it is demonstrated that after the simulations are set up accounting for the model differences, a reasonably good agreement is generally obtained, corroborating the correctness of the code results. When the halo current generation and its poloidal path in the first wall are included, however, the situation is more complicated. Because of the surface averaged treatment of the magnetic field (current density) diffusion equation, DINA can only approximately handle the poloidal electric currents in the first wall that cross the field lines. Validation is carried out for DINA simulations of the halo current generation by comparing with TSC simulations, where the treatment of halo current dynamics is more justifiable. The specific details of each code, affecting the consequence in ITER disruption prediction, are highlighted and discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
240. Development of a YAG laser system for the edge Thomson scattering system in ITER.
- Author
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Hatae, T., Yatsuka, E., Hayashi, T., Yoshida, H., Ono, T., and Kusama, Y.
- Subjects
- *
YAG lasers , *THOMSON scattering , *OPTICAL amplifiers , *SAMARIUM , *SEMICONDUCTOR doping , *PERFORMANCE evaluation - Abstract
A prototype YAG laser system for the edge Thomson scattering system in ITER has been newly developed. Performance of the laser amplifier was improved by using flow tubes made of samarium-doped glass; the small signal gain reached 20 at its maximum. As a result, an output energy of 7.66 J at 100 Hz was successfully achieved, and the performance exceeded the target performance (5 J, 100 Hz). [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
241. Polychromator for the edge Thomson scattering system in ITER.
- Author
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Yatsuka, E., Hatae, T., Fujie, D., Kurokawa, A., and Kusama, Y.
- Subjects
- *
OPTICAL instruments , *THOMSON scattering , *FUSION reactors , *SIGNAL processing , *PLASMA injection , *ELECTRIC discharges - Abstract
A new type polychromator has been designed for the edge Thomson scattering system in ITER. Signal light is parallelly dispersed into two parts at the first interference filter. Spectral transmissivities for some spectral channels may enhance better than the conventional type polychromator. In the new type polychromator, the misalignment due to the machine accuracy is expected to be within the margin of APD area. In order to calibrate the spectral transmissivity using the dual-laser injection method during the plasma discharge, it is preferred that the spectral channels are separated at the geometric mean of the injected two wavelengths. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
242. Plasma boundary and first-wall diagnostics in ITER
- Author
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Pitcher, C.S., Andrew, P., Barnsley, R., Bertalot, L., Counsell, G.G., Encheva, A., Feder, R.E., Hatae, T., Johnson, D.W., Kim, J., Kusama, Y., Lee, H.G., Mukhin, E.E., Reichle, R., Thomas, D.M., Tugarinov, S.N., Udintsev, V.S., Vasu, P., Vayakis, G., and Walker, C.I.
- Subjects
- *
PLASMA diagnostics , *FUSION reactor walls , *SIGNAL processing , *RADIATION shielding , *MATERIAL erosion , *NUCLEAR engineering - Abstract
Abstract: ITER plasma boundary and first-wall diagnostics are summarized in terms of their physical implementation and physics motivation. The challenge of extracting diagnostic signals while maintaining nuclear shielding is discussed, as well as the problems associated with high levels of erosion and redeposition. [Copyright &y& Elsevier]
- Published
- 2011
- Full Text
- View/download PDF
243. First Pediatric Case of Endocarditis Caused by Moraxella nonliquefaciens : Importance of Molecular Diagnosis.
- Author
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Yoshitake S, Kusama Y, Shiomi F, Nakahashi T, Toyota N, Yoshizawa K, Ito Y, and Kamimura K
- Subjects
- Humans, Male, Anti-Bacterial Agents therapeutic use, Molecular Diagnostic Techniques, Child, Female, Moraxellaceae Infections diagnosis, Moraxellaceae Infections drug therapy, Moraxellaceae Infections microbiology, Moraxella genetics, Moraxella isolation & purification, Endocarditis, Bacterial diagnosis, Endocarditis, Bacterial microbiology, Endocarditis, Bacterial drug therapy
- Abstract
Competing Interests: The authors have no funding or conflicts of interest to disclose.
- Published
- 2024
- Full Text
- View/download PDF
244. Can the "Access" percentage assess the antibiotic use appropriateness?
- Author
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Kusama Y
- Subjects
- Humans, Antimicrobial Stewardship statistics & numerical data, Anti-Bacterial Agents therapeutic use, Inappropriate Prescribing statistics & numerical data
- Abstract
Competing Interests: Declaration of competing interest None.
- Published
- 2024
- Full Text
- View/download PDF
245. An Infant With COVID-19 Presenting With a Bulging Fontanel: A Case Report and Literature Review.
- Author
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Kuroda H, Kusama Y, Ogura A, Matsunaga T, Atsumi Y, and Kamimura K
- Abstract
A bulging fontanel is a sign of elevated intracranial pressure, which can be caused by diseases with intracranial fluid retention or swelling of the cerebral parenchyma. We experienced a case of an infant with a typical course of mild coronavirus disease 2019 (COVID-19) but with a bulging fontanel as a finding at presentation. The patient, a three-month-old boy with no underlying conditions, presented to the emergency clinic with fever, vomiting, and loss of appetite. Due to the absence of crying and the bulging fontanel, he was referred to our hospital with suspected bacterial meningitis. The diameter of the anterior fontanel was 2.5 cm, as measured by the Popich and Smith method. He showed no signs of consciousness impairment and appeared to be as active as usual. Computed tomography revealed a bulging fontanel. Cerebrospinal fluid examination showed no elevated cell counts, and cultures were negative. Accordingly, bacterial meningitis was ruled out. The fever resolved on the day after admission, and the patient was discharged on the third day after admission in good general condition. When an infant diagnosed with COVID-19 presents with a bulging fontanel, it is important to be aware of its low specificity and excessive antibiotic treatment should be reconsidered., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Kuroda et al.)
- Published
- 2024
- Full Text
- View/download PDF
246. Factors Associated with Geographical Variability of Antimicrobial Use in Japan.
- Author
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Kitano T, Tsuzuki S, Koizumi R, Aoyagi K, Asai Y, Kusama Y, and Ohmagari N
- Abstract
Introduction: Evidence regarding the factors affecting the geographical variation of antimicrobial use (AMU) is relatively scarce. This study aimed to evaluate factors potentially associated with geographical variability of AMU per day per 1000 habitants in the 47 prefectures of Japan., Methods: This is an observational ecological study using the Japanese national database in 2019. The outcome was the defined daily doses per 1000 inhabitants per day by prefecture. Multivariable negative binomial regression analysis was conducted using patient- and physician-level variables., Results: The study included 605,391,054 defined daily doses of AMU in 2019 from the 47 prefectures. In the multivariable negative binomial regression analyses for the outcome of total AMU, the proportion of female individuals (adjusted rate ratio [aRR] 1.04 [1.01-1.08] per 1% increase, p = 0.021), the proportion of upper secondary graduates going to further education (aRR 1.01 [1.00-1.01] per 1% increase, p = 0.005), and the annual number of diagnoses related to upper respiratory infections (URIs) per 1000 inhabitants per day (aRR 1.21 [1.10-1.34], p < 0.001) were significantly correlated with total AMU., Conclusions: In this ecological study, the variability of total AMU by Japanese prefecture was associated with the proportion of female individuals, education level, and the number of URI diagnoses per population. The results suggest the potential need for additional stewardship efforts to reduce unnecessary antimicrobial prescriptions for URI., (© 2023. The Author(s).)
- Published
- 2023
- Full Text
- View/download PDF
247. Guidelines for the Management of Respiratory Infectious Diseases in Children in Japan 2022.
- Author
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Ishiwada N, Shinjoh M, Kusama Y, Arakawa H, Ohishi T, Saitoh A, Suzuki A, Tsutsumi H, Nishi J, Hoshino T, Mitsuda T, Miyairi I, Iwamoto-Kinoshita N, Kobayashi H, Satoh K, Shimizu A, Takeshita K, Tanaka T, Tamura D, Tokunaga O, Tomita K, Nagasawa K, Funaki T, Furuichi M, Miyata I, Yaginuma M, Yamaguchi Y, Yamamoto S, Uehara S, Kurosaki T, Okada K, and Ouchi K
- Subjects
- Child, Humans, Japan epidemiology, Communicable Diseases diagnosis, Communicable Diseases epidemiology, Communicable Diseases therapy, Respiratory Tract Infections diagnosis, Respiratory Tract Infections drug therapy, Respiratory Tract Infections epidemiology
- Abstract
The members of the Japanese Society for Pediatric Infectious Diseases and the Japanese Society of Pediatric Pulmonology have developed Guidelines for the Management of Respiratory Infectious Diseases in Children with the objective of facilitating appropriate diagnosis, treatment and prevention of respiratory infections in children. The first edition was published in 2004 and the fifth edition was published in 2022. The Guideline 2022 consists of 2 parts, clinical questions and commentary, and includes general respiratory infections and specific infections in children with underlying diseases and severe infections. This executive summary outlines the clinical questions in the Guidelines 2022, with reference to the Japanese Medical Information Distribution Service Manual. All recommendations are supported by a systematic search for relevant evidence and are followed by the strength of the recommendation and the quality of the evidence statements., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)
- Published
- 2023
- Full Text
- View/download PDF
248. Investigation of oral macrolide prescriptions in Japan using a retrospective claims database, 2013-2018.
- Author
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Ide S, Ishikane M, Aoyagi K, Ono A, Asai Y, Tsuzuki S, Kusama Y, Gu Y, Kodama E, and Ohmagari N
- Subjects
- Humans, Macrolides therapeutic use, Retrospective Studies, Japan, Anti-Bacterial Agents therapeutic use, Prescriptions, Observational Studies as Topic, Common Cold drug therapy, Anti-Infective Agents, Hypersensitivity drug therapy
- Abstract
Macrolide usage in Japan exceeds that in Europe and the United States. Investigating the actual conditions in which macrolides are used is important for identifying further interventions for appropriate antimicrobial use; however, this situation has not been evaluated in Japan. Therefore, we aimed to clarify the number of macrolide prescriptions and their changes before and after implementation of the Antimicrobial Resistance (AMR) Action Plan. In addition, we also investigated the names of diseases for which macrolides have been prescribed and the number of days of prescription. A retrospective observational study was conducted using JMDC claims data from January 2013 to December 2018. The proportion of all oral antimicrobials and macrolides used during this period and the diseases for which macrolides were used in the 3 years before and after the AMR Action Plan were determined separately for acute (< 14 prescription days) and chronic (> 14 prescription days) diseases. The number of prescriptions for macrolides constituted approximately 30% of those for all oral antimicrobials; of these, clarithromycin accounted for approximately 60%. Most prescriptions for acute diseases were for common cold, whereas allergic and dermatological diseases were included among chronic diseases. The names of these illnesses did not change before and after the AMR Action Plan. Overall, these results indicate that appropriate macrolide use involves a review of their use for common cold along with appropriate evaluation of their long-term use for skin and allergic diseases. They also indicate the need for further fact-finding studies and ongoing AMR measures., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Ide et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
- Published
- 2023
- Full Text
- View/download PDF
249. Intussusception Initially Diagnosed as a Brief Resolved Unexplained Event (BRUE).
- Author
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Atsumi Y, Kusama Y, Fukui S, and Kamimura K
- Abstract
Brief resolved unexplained event (BRUE) are transient and worrying episodes observed in infants and are characterized by changes in skin color, breathing, muscle tone, and/or responsiveness. We describe the case of a female infant who was initially diagnosed with BRUE but was later determined to have intussusception. She presented to our emergency department with a transient pallor and a single episode of vomiting that resolved before her visit. Physicians did not detect any abnormalities on physical or laboratory examinations, so she was diagnosed with BRUE and discharged to be re-evaluated the next day. After returning home, she vomited several times. The patient revisited our hospital the following day and was definitively diagnosed with intussusception using ultrasonography, which was successfully treated using fluoroscopy-guided hydrostatic reduction. This case was initially diagnosed as a BRUE; however, re-evaluation helped in identifying the proper diagnosis of intussusception. Physicians should exercise caution when diagnosing patients with BRUE. When the diagnostic criteria are not completely met, follow-up should be conducted, assuming that the patient has a potentially serious condition., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Atsumi et al.)
- Published
- 2023
- Full Text
- View/download PDF
250. Two Pediatric Cases of Food Protein-Induced Enterocolitis Syndrome to Soy Eaten as an Infant Food.
- Author
-
Maeda K, Kusama Y, Atsumi Y, Takahara T, and Kamimura K
- Abstract
Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE-mediated food allergy that can be caused not only by infant formula but also by infant food. Herein, we report two pediatric cases of FPIES to solid soy foods, such as tofu. The patients presented with repetitive vomiting after eating the trigger food as infant food. Although both cases promptly recovered following the cessation of the trigger food, one case required rapid intravenous hydration for compensated shock. Both cases were diagnosed with FPIES to soy based on the typical presentation and parental interviews regarding food exposure. One case had a positive response to an oral food challenge for tofu, and both cases were negative for soy-specific IgE. One of our cases did not develop FPIES from fermented soy products despite having soy-triggered FPIES. The fermentation process may reduce the allergenicity of soy, but further evidence is required to confirm this hypothesis. There are various trigger foods for solid food FPIES (SFF), and these differ among countries. Solid food FPIES to soy is more common in Japan than in other countries due to the frequent use of tofu in infant food. Increased international awareness of the possibility of tofu-triggered FPIES may be warranted due to the rising global use of tofu in infant food., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Maeda et al.)
- Published
- 2023
- Full Text
- View/download PDF
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