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Background:There are only very few reports of cervical toxoplasma lymphadenitis being diagnosed exclusively via fine-needle aspiration cytology (with serology).Case report:We describe a case of toxoplasma lymphadenitis that was successfully diagnosed by fine-needle aspiration cytology. The case involved a male patient who was immunocompromised as a result of recurrent acute myelogenous leukaemia with cervical lymphadenopathy. The biopsy showed typical features of a well-defined pseudocyst containing Toxoplasma gondii tachyzoites.Conclusion:Toxoplasma lymphadenitis is a common cause of lymph node enlargement. Fine-needle aspiration cytology is a useful method for diagnosing and differentiating toxoplasma lymphadenitis from more serious causes of lymphadenopathy, such as metastatic lymphadenopathy or lymphoma. [ABSTRACT FROM PUBLISHER]

Reports on the high performance and steady-state experiments that have been conducted in the W-shaped divertor in the Japan Atomic Energy Research Institute Tokamak-60 Upgrade. Equivalent deuterium-tritium fusion multiplication factor; Reduction in particle diffusivity in the internal transport barriers region of the reverses shear plasma.

We studied cells in the lungs of BALB/c and BALB/c-nu/nu (nude) mice infected with Toxocara can/s, which produced interleukin-5 (IL-5) in in vitro culture with larval excretory-secretory antigen (ESAg). The proportion of CD4+/CD8+/CD4-CD8- cells in lungs of both BALB/c and nude mice was unchanged before and after infection with T. canis. Panning and complement mediated lysis using monoclonal antibody (mAb) to CD4 showed that CD4+ cells in the lung from both mice produced IL-5. Anti-CD4 mAb suppressed ESAg-stimulated IL-5 production in vitro. In vitro depletion or inhibition of CD8+ cells reduced IL-5 production significantly in some cases, suggesting involvement with IL-5 production. Anti-CD3 mAb enhanced IL-5 production when incubated with or without ESAg. Production of IL-5 was reduced by in vivo depletion of CD4+ cells only and both CD4+ and CD8+ T cells, by intraperitoneal injection with appropriate mAb; IL-5 production was stimulated by anti-CD3 mAb. In contrast, IL-5 production by lung cells of BALB/c mice decreased by more than 90% after simultaneous injection with anti-CD4, anti-CD8 and anti-CD3 mAb, and was not enhanced by anti-CD3 mAb. Similar results were obtained in nude mice. These results suggest that CD4- CD8- T cells, as well as CD4+ T cells, produce IL-5. [ABSTRACT FROM AUTHOR]

We undertook a search for cytokine-inducible molecules present on brain endothelium and which are involved in the control of lymphocyte adhesion. We screened 39 monoclonal antibodies (mAb) against rat brain endothelium in vitro, and identified five recognizing cytokine-inducible molecules. None of the 39 antibodies blocked lymphocyte adhesion, but one antibody (4A2), produced a 400% enhancement of lymphocyte binding. The 4A2 antigen is induced on brain endothelium by interferon-γ (INF-γ) but not tumour necrosis factor-α (TNF-α), at 6-48 hr. It is preferentially expressed near inter-endothelial cell junctions, but it is also expressed on all lymphocytes and weakly on aortic endothelium in vitro. In vivo, it is not detectable on cells in the normal central nervous system (CNS), however it appears in the CNS during T-cell mediated immune reactions. Triggering of cells via this molecule enhances integrin-mediated adhesion of lymphocytes to brain endothelium, primarily via LFA-1. Unlike ICAM-1, 4A2 antigen is induced on endothelium of both Lewis and PVG strains. Although, it has some functional properties of human CD31, the 4A2 antigen is not rat CD31. The cellular localization of this molecule, its actions on integrin-mediated adhesion and its induction by IFN-γ, all indicate that the 4A2 antibody recognizes a molecule involved in the control of lymphocyte migration into the brain. [ABSTRACT FROM AUTHOR]

Regardless of the availability of resources in the hospital, approximately half of these hospitals assigned AMU calculation to pharmacists in their off-duty hours. B Background: b Monitoring of antimicrobial use (AMU) is required in all hospitals to comprehensively track the process of antimicrobial stewardship. [Extracted from the article]

A natural diamond detector (NDD) has been installed on the JT-60U tokamak to measure the flux and the energy distribution of charge exchange (CX) fast neutral particles. A NDD has many important advantages to be used as a CX neutral particle analyzer, for example very compact size, high energy resolution, and high radiation hardness etc., while the neutrons and γ rays are a large noise source in the deuterium plasma. The shield was set up around the NDD to reduce those noises. Time-resolved energy distribution of CX neutral particles corresponding to injected beam energy have been successfully obtained under high intensity neutron yield Yn>1015 n/s. Further enhanced neutral particle fluxes during sawtooth oscillation and Alfvén eigenmodes were observed with the NDD. The performance of the NDD as CX neutral particle spectrometer under high intensity neutron yield was demonstrated for the first time on JT-60U in this work. [ABSTRACT FROM AUTHOR]

In this paper, the shielding effects for various door seals of a microwave oven are discussed. The FDTD method is adopted in the numerical calculations. It is shown here that there are optimum combinations of part sizes and structures by which the high shielding effect is obtained. © 1998 John Wiley & Sons, Inc. Microwave Opt Technol Lett 19: 333–335, 1998. [ABSTRACT FROM AUTHOR]

Develops a charge-exchange neutral particle beam analyzer for the measurement of the MeV energy range ions produced by nuclear fusion or radio frequency heating. Ionization of neutral particles entering the analyzer with a carbon foil thickness; Resolution of energy and mass of the stripped ions.

An E//B type neutral particle analyzer with an acceleration tube between a stripping cell and a deflection magnet has been developed to measure ion energy distributions in a wide energy range from thermal ions to fast ions up to several hundred kiloelectron volts simultaneously without making the analyzer size large. In the acceleration tube, ions are accelerated up to the detectable energy before coming into the deflection magnetic field. The acceleration method enables us to detect low-energy ions even for a strong deflection magnetic field to measure high-energy ions. Calibration experiments confirmed that ions were well accelerated according to expectation without degrading the abilities of the analyzer. The energy dynamic range E[sub max]/E[sub min] was improved up to 100 by the acceleration method. Using the analyzer, ion energy distributions have been measured in various heating experiments of JT-60. [ABSTRACT FROM AUTHOR]

In reactor-grade tokamaks, it is important to investigate confinement properties of alpha particles. A double charge-exchange method using a high-energy probing beam is considered to be the most reliable one in diagnostic methods proposed for the measurement. In JT-60U, an alpha particle production experiment by D-³He ICRF heating will be performed to study the behavior of fusion product alphas. The alpha particle measurement is planned using a helium diagnostic beam (200 keV) and a mass-resolved neutral panicle energy analyzer. The expected flux and spectral shape were evaluated by taking into account multistep ionization of helium beam atoms and neutralized alphas. The beam energy is lower than desirable for measuring fast confined alphas near the birth energy. However, by using the beam system, it has been found from the evaluation that we can investigate the confinement properties of fusion product alphas from the spectral shape. And also such a system using a present-day He beam is useful to diagnose behavior of confined alphas in reactor-grade tokamak such as ITER. [ABSTRACT FROM AUTHOR]

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]

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]

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]

Fusion gamma rays were measured in D–[sup 3]He experiments using negative ion-based neutral beam injection (N-NBI) in reverse shear plasmas of the JT-60 tokamak. [sup 3]He gas was puffed at plasma initiation and just before N-NB injection. The D–[sup 3]He reaction produces 3.6 MeV alphas and 14.7 MeV protons, but there is also a small branch which provides [sup 5]Li and 16.7 MeV gamma rays. The total D–[sup 3]He reaction rate can be evaluated from measurement of gamma rays of the [sup 3]He (d,γ) [sup 5]Li reactions using a 3 in. diam by 3 in. long Bi[sub 4]Ge[sub 3]O[sub 12] scintillator. The gamma-ray detector was located 17 m below the plasma center and measured the gamma-rays in a vertical line of sight. The detector was mounted inside a heavy collimator with polyethylene and lead shielding. The floor penetration, a 4×8 cm[sup 2] hole, was used as a precollimator. Energy calibration of the detector was done with photopeaks for neutron capture gamma rays from the structural materials in D–D discharges. The detection efficiency was calculated with Monte Carlo code MCNP-4B for 16.7 MeV gammas. The pulse height analysis of the gamma rays resulted in the D–[sup 3]He fusion power of 110±30 kW in this experiment. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

In order to measure the ion temperature of the JT-60 tokamak, we have developed a Rutherford scattering system using a helium atom beam. A positive-ion beam generated by an ion source which has a capability of beam energy 200 keV and drain current 3.5 A is converted to a helium atom beam by collision with cold helium gas. The He atom beam, equivalent to 0.6 A, reaches the center of the vacuum chamber of the JT-60 tokamak. The scattering angle is 7.0°. Scattered helium atoms are analyzed by an EB-type neutral particle energy analyzer with a gas stripping cell. This scattering system has been applied to investigate additionally heated plasmas by the method of neutral beam injection (NBI), ion cyclotron wave (ICRH), lower hybrid wave (LHRH), and combined heating of NBI + LHRH or ICRH in a parameter range of B[sub t] = 4.0 to 4.5 T, I[sub p] = 1.0 to 3.2 MA, and ñ[sub e] ... 1 × 10[sup 20] m[sup -3]. The ion temperatures obtained by the system are consistent with those measured by Doppler broadenings of Ti XXI and Ti XXII resonance lines. To investigate the influence of ion temperature and density profiles and the beam component of NBI heating on the determination of ion temperature, we have evaluated an energy spectrum of scattered atoms by using a simulation code. The result shows that in JT-60 plasmas the beam component hardly exerts an important influence on the determination of ion temperature by this diagnostic system. [ABSTRACT FROM AUTHOR]

Focuses on the application of a two-dimensional measurement with an infrared television camera to toroidal field (TF) ripple loss study. Content of the study; Information concerning the thermal measurement of fast ion behaviors.

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

Rapid frequency sweeping modes observed in reversed magnetic shear (RS) plasmas on the Japan Atomic Energy Research Institute Tokamak 60 Upgrade (JT-60U) [H. Ninomiya and the JT-60 Team, Phys. Fluids B 4, 2070 (1992)] have been identified as reversed-shear-induced Alfvén eigenmodes (RSAEs), which are ideal magnetohydrodynamic Alfvén eigenmodes (AEs) localized to the region of minimum safety factor, qmin, and are excited by negative-ion-based neutral beam injection. The chirping and subsequent saturation of the mode frequency are consistent with theoretical predictions for the transition from RSAEs to toroidal Alfvén eigenmodes (TAEs). The previously observed rapid frequency sweeping modes in ion cyclotron wave heated plasmas in JT-60U can also be similarly explained. The observed AE amplitude is largest during the transition from RSAEs to TAEs, and fast ion loss is observed when the AE amplitude is largest at this transition. It is preferable to operate outside the transition range of qmin, e.g., 2.4

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]

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]

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]

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]

A ferritic steel wall, which might be employed in fusion demonstration reactors, has been installed in Japan Atomic Energy Research Institute Fusion Torus-2 Modified [Nucl. Fusion 41, 257 (2001)] to study the applicability of ferromagnetic walls to plasmas. The tearing mode equation is solved in presence of a ferromagnetic/resistive wall to study the effect of the ferromagnetism on the tearing mode stability in tokamaks. It is shown that a ferromagnetic wall has a weak effect on the surface tearing modes depending on the current profile. The destabilization effect due to the attraction of the perturbed magnetic field by permeability is shown to be very small compared to the stabilization effect of the conducting wall. [ABSTRACT FROM AUTHOR]

Short duration (20 msec) neutral deuterium beams are injected into the TFTR tokamak [Plasma Physics and Controlled Nuclear Fusion Research 1986 (IAEA, Vienna, 1987), Vol. I, p. 51]. The subsequent confinement, thermalization, and diffusion of the beam ions are studied with multichannel neutron and charge exchange diagnostics. The central fast-ion diffusion (<0.05 m2/sec ) is an order of magnitude smaller than typical thermal transport coefficients. [ABSTRACT FROM AUTHOR]

Steady-state and perturbative transport analysis are complementary techniques for the study of transport in tokamaks. These techniques are applied to the investigation of auxiliary-heated Lmode and supershot plasmas in the tokamak fusion test reactor (TFTR) [R. J. Hawryluk et al., Plasma Physics and Controlled Nuclear Fusion Research, Proceedings of the 11 th International Conference, Kyoto, 1986 (IAEA, Vienna, 1987), Vol. 1, p. 51. ]. In the L mode, both steady-state and perturbative transport measurements reveal a strong temperature dependence that is consistent with electrostatic microinstability theory and the degradation of confinement with neutral beam power. Steady-state analysis of the ion heat and momentum balance in supershots indicates a reduction and a significant weakening of the power-law dependence on the transport in the center of the discharge. [ABSTRACT FROM AUTHOR]

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]

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]

A high-repetition and high-energy transversely excited atmospheric carbon dioxide (CO2) laser for a collective Thomson scattering (CTS) diagnostic has been developed to establish a diagnostic method of confined α particles in burning plasmas. To excite a single-transverse and single-longitudinal mode, a continuous wave seed laser was injected to an unstable resonator with a cavity length of ∼4.4 m. Pulse energy of 10 J with a repetition rate of 10 Hz has been achieved in the single-mode operation. Pulse energies of 18 J with a repetition rate of 10 Hz and 36 J with single shot operation have also been achieved in the multimode operation. These results give a prospect for the CTS diagnostic on International Thermonuclear Experimental Reactor (ITER), which requires single-mode energy of 20 J with repetition rate of 40 Hz. [ABSTRACT FROM AUTHOR]

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]

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]

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]

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]

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.