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The plasma position and shaping, and the plasma current are controlled by poloidal field (PF) coils consisting of superconductors, and the fast plasma position change is controlled by in-vessel coils consisting of normal conductors on recent tokamaks. The coil current response for the voltage command value depends on the time constant of the coil. The in-vessel coils have a much faster coil current response than PF coils due to the short time constant. Therefore, the decoupling control between in-vessel coils and PF coils respecting each coil current response must be established. In this study, we introduce the issues given by the coupling of in-vessel and PF coils controls and demonstrate the improved control by the decoupling., 48th European Conference on Plasma Physics

Previous studies reported that cigarette smoking during radiation therapy was associated with unfavorable outcomes in various cancers using medical interviewing or monitoring of cotinine. Here, we evaluated the effect of smoking cessation on definitive radiation therapy for early stage glottic carcinoma by monitoring expiratory carbon monoxide (CO).We enrolled 103 patients with early glottic carcinoma (T1N0/T2N0 = 79/24) who underwent conventional radiotherapy between 2005 and 2016. The median age was 70 years. Pathologically, all patients had squamous cell carcinoma. Since 2009, we confirmed smoking cessation before radiation therapy by medical interviews. Since 2014, we measured expiratory CO to strictly monitor smoking cessation. The patients were divided according to diagnosis years: 'no cessation' (2005-2008), 'incomplete cessation' (2009-2013), and 'complete cessation' (2014-2016). We retrospectively analyzed the local recurrence rate and disease-free survival (DFS).The median follow-up period was 60.1 months (range, 1.9-110.0 months). The 2-year local recurrence rate in the 'complete cessation' group was 5.3% and tended to be lower than that in the 'incomplete cessation' group (13.7%) and 'no cessation' group (21.2%). Multivariate analysis revealed that 'no cessation' was a risk factor for DFS (hazard ratio [HR] = 4.25) and local recurrence rate (HR = 16.5,We confirmed that the 'complete cessation' group had better prognosis than the 'no cessation' group by monitoring expiratory CO during radiation therapy for early stage glottic carcinoma. Moreover, monitoring expiratory CO was easier and more suitable than conventional methods for evaluating smoking cessation because it provided real-time measurements.

To resolve concerns for heat/electromagnetic loads from vertical displacement events (VDEs), we developed an equilibrium controller, which can predict and control VDEs to an arbitrary direction and allows us to cope with either upward or downward unmitigated VDEs. Here we improve the prediction rate by parameterizing a power supplies voltage saturation rate with a newly developed adaptive voltage allocation (AVA) scheme. Furthermore, the AVA scheme also broadens accessible elongation by 0.3 in the presence of power supplies voltage saturation due to hybrid plasma current and shape/position control and unknown plasmas disturbances. In preparation for coming JT-60SA integrated commissioning, the VDE predictor and the AVA scheme are implemented in our equilibrium controller, and its performance is demonstrated by using MHD Equilibrium Control Simulator “MECS”.

垂直位置不安定性による垂直位置移動現象（VDE）の制御はプラズマの高性能化に向け必要不可欠である。特に、高プラズマ閉じ込め、高プラズマ電流駆動に寄与する高楕円度プラズマは、VDEが発生しやすい。また、小規模なプラズマ電流崩壊、β崩壊や、L-Hモード遷移などが発生する際には、プラズマ形状、位置が急激に変化し、VDEや水平位置移動現象（HDE）が生じる。VDE、HDEの制御には高速位置制御が必要である。JT-60SAにおけるプラズマ平衡制御コイル群は10本の超伝導コイル群と2本の真空容器内常伝導コイル群より構成されており、超伝導コイル群はプラズマ電流制御、形状制御を行い、低コイル時定数で、プラズマとの距離が近い位置に設置される真空容器内常伝導コイル群（高速プラズマ位置制御コイル（FPPCコイル））が高速位置制御を行う。本研究では、プラズマ電流崩壊に伴うVDEの制御性向上を図ることを目的に、FPPCコイルによる高速位置制御手法を、MHD平衡制御シミュレータ（MECS）を用いて開発・検証した。, 第38回プラズマ核融合学会 年会

The ITER Remote Experimentation Centre (REC) project (one of the three sub-projects of the International Fusion Energy Research Centre (IFERC)) is progressing under the agreement between the Government of Japan and the European Atomic Energy Community for the joint implementation of the Broader Approach (BA) activities in the field of fusion energy research. The objectives of the REC activity are to identify the functions and solve the technical issues for the construction of the REC for ITER at Rokkasho, and to develop the remote experiment system and verify the functions required for remote experimentation by using the Satellite Tokamak (JT-60SA) facilities to facilitate the future exploitation of ITER and JT-60SA. The functions of REC will be tested, and the total system will be demonstrated using JT-60SA and existing facilities in the EU, such as JET and WEST. The hardware of the REC has been prepared in Rokkasho Japan, which has the remote experiment room with a large video wall to show the plasma and operation status, IT equipment and a storage system by the reuse of the Helios supercomputer tape library. A broadband network infrastructure of 10Gbps has been installed connected to SINET5. Using this network system, fast data transfer from ITER to REC was examined in 2016, and the transfer of the data volumes expected for the initial ITER experiments has been demonstrated. A secure remote experimentation system has been developed, using JT-60SA, that has functions for preparing and setting of shot parameters, viewing the status of control data, streaming of the plasma status, data-exchange function of shot events, and monitoring of the facility operation. Remote data analysis techniques, data visualisation software, a documentation management and experiment planning system and numerical simulation codes for the preparation and performance estimation of discharges have also been developed.

An advanced ISO-FLUX equilibrium control scheme is developed and implemented in the JT-60SA equilibrium controller, which is essential for vertical displacement event (VDE) control under DEMO reactor relevant device conditions.Since conditions for VDE control in the DEMO reactor are highly disparate from that in present day tokamaks and even from that in ITER, such as the absence of in-vessel coils and stabilization plates, a large gap between plasmas and vacuum vessels, and eddy currents flowing in the breeding blanket, etc., thus improvement of the conventional control scheme is required. The developed scheme not only adaptivelyadjusts balance between plasma position/shape control and plasma current controlwithin limited power supply voltages, where plasma current control affects plasmaposition/shape control, and vice versa, but also robustly controls position of plasmasin the presence of the large eddy currents. Those two schemes contribute to enhancethe VDE controllability under the DEMO relevant device conditions. More specifically,the advanced ISO-FLUX control scheme broadens the operation window with the safe-margin from the unpredicted disturbances, which stem from auxiliary heating andminor-disruptions. The JT-60SA equilibrium controller with the developed scheme iswell verified by a magnetohydrodynamic equilibrium control simulator "MECS" andready for the integrated commissioning of JT-60SA, whose device condition is notablyrelevant to the DEMO reactor.

Divertor simulation study has been started as a new research plan, by making best use of a large linear plasma device. The experiment of generating the plasma flow with high heat and particle flux was successfully performed at an end-mirror exit of the GAMMA 10 tandem mirror. In typical hot-ion-mode plasmas, the heat-flux density of 0.6 MW/m2 and the particle-flux density of 1022 particles/s m2 were simultaneously achieved in the case of only ICRF heating and superimposing the 300 kW ECH pulse attained the peak value of the net heat-flux up to 8 MW/m2 on axis. The above experimental results and the simulation analysis of ICRF heating using the Fokker-Planck code give a clear prospect of generating the required performance for divertor studies by building up the plasma heating systems to the end-mirror cell. Detailed behavior of the plasma flow and the future research plan are also described. © 2010 Elsevier B.V. All rights reserved.

The suppression of the potential fluctuation was clearly observed by a gold neutral beam probe (GNBP) during the higher potentials and positive electric fields driven by electron cyclotron heating. The particle flux evaluated from the phase difference between the potential and density fluctuations measured by GNBP showed the radial outward flux and correlates with the decrease in the stored energy. When flux is suppressed by the potential formation, the quick plasma stored energy increase is observed.

In the tandem mirror GAMMA 10, plasma confinement is achieved not only by the magnetic mirror configuration but also by the high potentials at both end regions. Before applying plug–electron cyclotron resonance heating (P-ECH), drift-type fluctuations were observed in the potential and density measurements. The suppression potential and density of these fluctuations were clearly determined by using a gold neutral beam probe (GNBP) system during the potential formation by the application of P-ECH. We studied the relationship between the suppression levels of the potential fluctuations and the effects of potential produced by changing the applied electron cyclotron heating power. Moreover, the particle-flux-related values obtained by examining the phase difference between the potential and density fluctuations were measured by using the GNBP. We clearly show that radial anomalous transport induces radial particle transport, which decreases the stored energy of the plasma.

As the new research plan of Plasma Research Center of the University of Tsukuba, we are planning to start a study of divertor simulation under the closely resemble to actual fusion plasmas environment making an advantage of the GAMMA 10 tandem mirror and to contribute the solution for realizing the divertor in future toroidal systems. In the research plan, the concepts of two divertor devices are introduced. One has an axi-symmetric divertor configuration with separatrix (A-Div.) and the other is a high heat flux divertor simulator by using an end-mirror exit of the large tandem mirror device (EDiv.). Preparative experiments have been successfully started at the end-mirror region of GAMMA 10 and detailed behavior of end-loss particles has been investigated by using newly developed diagnostic instruments. In standard hot-ion mode plasmas (ne0 ~ 2x1018 m-3, Ti0 ~ 5 keV), the heat flux density of 0.8 MW/m2 and the particle flux density of 4x10 22 /s·m2 were observed at 30 cm downstream of the end-mirror exit on the machine axis. It is confirmed that the heat flux density increases in proportion to the applied RF power. Superimposing the ECH pulse induces a remarkable enhancement of heat flux and a peak value in the net heat flux density of 8 MW/m2 was attained during the ECH injection, which almost comes up to the heat load level of the divertor plate of ITER. Two-dimensional visible image measurement of newly installed target plates using highspeed camera revealed a significant difference in the behavior of visible emission from plasma-material interaction. The above results give a clear prospect of generating the required performance and providing useful information for divertor studies in GAMMA 10.

We are planning to start a study of divertor simulation under the closely resemble to actual fusion plasma environment making use of the advantage of open magnetic field configuration and to contribute the solution for realizing the divertor in ITER as a future research plan of Plasma Research Center of the University of Tsukuba. In the research plan, the concepts of two divertor devices are introduced. One has an axi-symmetric divertor configuration with the separatrix which is similar to toroidal divertor of torus systems and the other is a high heat flux divertor simulator by using an end-mirror exit of the existing tandem mirror device. Development of magnetic field configuration for ensuring the MHD stability is under way and a designed example is investigated under the optimal condition for plasma production. Consideration of plasma heating scheme using Fokker-Planck simulation code was successfully performed at both axi-symmetric divertor and end-mirror regions. Preparative experiments using calorimeter, Mach probe and high-speed camera have been started at the end-mirror region and the heat flux density of the level in 1-10 MW m -2 was achieved in standard hot-ion mode plasma-confining experiments, which gives a clear prospect of generating the required heat flux density for divertor studies. © 2010 Elsevier B.V.

Recent progress and near future plan of GAMMA 10 efforts are presented. With high power plug electron cyclotron heating (ECH) up to ~ 400 kW, the ion confining potential of more than 2 kV was confirmed. The drift type low frequency fluctuations were suppressed by the positive radial electric field produced by plug ECH. It is found that the efficient EC heating on mirror devices from a strong B field side requires the minimization of the stray microwave in addition to the 100% X-mode excitation to avoid the enhancement of the ion loss. The development of a gyrotron, the key tool of these ECH experiments, has been made in collaboration with NIFS (National Institute for Fusion Science), More than 1.5 MWfor more than Is has been demonstrated at 77GHz. The plan of the boundary plasma research program with modification of GAMMA 10 is in progress. The new program includes the physics and technology studies of the divertor and SOL plasmas and PWI relevant to torus plasmas like ITER. The high heat flux experiments using the open end mirror throat has been started and we have obtained successful preliminary data, which include the heat flux of 8 MW/m2.

The electrostatic fluctuation was observed by a heavy ion beam probe (HIBP) at the central cell in the GAMMA 10 tandem mirror. The fluctuation of the end plates settled at both side of GAMMA 10 was...

A study of fluctuation is one of main issues in fusion plasma researches. In the tandem mirror GAMMA10, a potential fluctuation changes during the formation of confinement potential with the application of electron cyclotron heating (ECH). Potential fluctuation induces radial particle transports. We have studied the radial profiles of the potential fluctuation during the application of ECH. The potential in the central cell of GAMMA10 is measured by a gold neutral beam probe (GNBP) system. GNBP is a useful tool for the study of radial potential and its fluctuation directly in the fusion plasmas. It was confirmed that the stronger radial potential was formed during the application of plug ECH than that without plug-ECH.

Refueling by hydrogen ice pellet injection has been studied in various plasmas. The research of pellet ablation related to refueling is very important object. In the central-cell plasma of tandem mirror GAMMA 10, we measured the position of pellet ablation by vertical and horizontal arrays of Ha detectors and a high-speed CMOS camera. We found that the penetration depths with applying electron cyclotron heating (ECH) is shorter than that without ECH. It suggests that the pellet ablation is strongly affected by warm electrons produced with ECH. Moreover, we investigated the effects of neutral beam injection (NBI) to the pellet ablation, which showed the pellet ablation in the situation of higher density plasma. The pellets penetrate through the plasma without applying ECH or NBI. We observed the pellet ablation at each position by using vertical and horizontal arrays of Ha detectors and a high-speed CMOS camera with the interference filter.

There is a radial particle transport as the loss induced by the fluctuations. It is possible to measure the potential and density fluctuations at the arbitrary point simultaneously by using gold neutral beam probe, and their phase difference between them. The radial particle transport induces the decreasing of the plasma stored energy. This phenomenon is estimated the theoretically-predicted loss process induced by the radial transport due to the phase difference between the potential and density fluctuations.

Considerable interests have been focused on the study of turbulent fluctuations in magnetic confinement system, since various theories predict such turbulent fluctuations lead to anomalous transport and energy loss in the transverse direction. Density fluctuations during the formation of the confinement potential with application of electron cyclotron heating (ECH) in GAMMA 10 were studied by using both the multi-channel microwave interferometer and gold neutral beam probe. It is found that low frequency fluctuation, which corresponds to the diamagnetic drift, is suppressed during the formation of confining potential by the application ofplug-ECH.

Generalized scaling laws for the formation of plasma confining potentials are investigated to find the physics essentials common to representative tandem-mirror operational modes in GAMMA 10. These modes are characterized in terms of (i) a high-potential mode and (ii) a hot-ion mode. The potential-formation scalings in these modes are consolidated and generalized on the basis of the consistency with finding of the wider validity of Cohen's strong electron-cyclotron heating (ECH) theory covering over both modes. A plateau-shaped electron distribution function is observed when a plug electron-confining potential is formed in the hot ion mode of GAMMA 10, as predicted in terms of the strong ECH theory.

(1) Four-time progress in ion-confining potentials Φ c to 3.0 kV in comparison to Φ c attained 1992-2002 is achieved in the hot-ion mode (T i =several keV). A scaling of Φ c , which favorably increases with plug electron-cyclotron heating (ECH) powers (P PECH ), is obtained. (2) The advance in Φ c leads to a finding of remarkable effects of radially sheared electric fields (dEr/dr) on turbulence suppression and transverse-loss reduction. (3) A weak decrease in Φ c with increasing n c to ∼10 19 m -3 with the recovery of Φ c with increasing P PECH is obtained. (4) The first achievement of active control and formation of an internal transport barrier (ITB) has been carried out with the improvement of transverse energy confinement. Off-axis ECH in an axisymmetric barrier mirror produces a cylindrical layer with energetic electrons, which flow through the central cell and into the end region. The layer, which produces a localized bumped ambipolar potential Φ c , generates a strong E r shear and peaked vorticity with the direction reversal of E r ×8 sheared flow near the Φ c peak. Intermittent vortex-like turbulent structures near the layer are suppressed in the central cell. This results in T e and T i rises surrounded by the layer. The phenomena are analogous to those in tokamaks with ITB. (5) Preliminary central ECH (170 kW, 20 ms) in a standard tandem-mirror operation raises T e0 from 70 to 300 eV together with T ι⊥0 from 4.5 to 6.1 keV, and T i//0 from 0.5 to 1.2 keV with τ P0 =95 ms for Φ c (=1.4 kV) trapped ions. The on-axis particle to energy confining ratio of τ P0 /τ E0 is observed to be 1.7 for Φ c trapped ions (consistent with Pastukhov's theory) and 2.4 for central mirror-trapped ions with 240-kW plug ECH and 90-kW ICH (η ICH ∼0.3; nl c =4.5×10 17 m -2 ). (6) Recently, a 200 kW central ECH with 430 kW plug ECH produces stable central-cell plasmas (T e =600 eV and T i =6.6 keV) with azimuthal E r ×B sheared flow. However, in the absence of the shear flow, hot plasmas migrate unstably towards vacuum wall with plasma degradation.

The efficacy of hyaluronic acid (HA) gel in adhesion prevention was evaluated in the rat cecal abrasion model. The HA gel was produced by a simple freezing process using an acidic HA solution, and ...

We estimate the influence of the discrepancy of the cross sectional shapes between the magnetic flux tube and the equi-potential surface at the mirror throats of the anchor cell on the radial drift of the plug potential bounce ion. The radial potential profiles are assumed to be Gaussian. It is found that the discrepancy enhances the radial drift of the bounce ion and the spread radial potential profile moderates the enhancement. The radial potential profile of the core plasma is adjusted by controlling the electrostatic potentials of the coaxially separated end plate. It is found that the spread type of radial potential profile is effective for the retardation of the radial transport of the bounce ions.

The efficacy of novel hyaluronic acid (HA) gel manufactured using a freezing procedure from an acidic HA solution was evaluated in a rat cecal abrasion model. HA gel films with different half-lives (50–200 hours) in a physiologic buffered saline at 37°C were prepared by regulating the freezing time. In the mouse peritoneal implantation, the HA gel films were absorbed more slowly than the freeze-dried HA film and the degradation property depended on the degree of the crosslinking reaction. The HA gel film, which was 4 × 4 cm in size (1.5 mg HA/cm2), was applied to the injured cecal surface in rats after standardized treatment with rotary abrasion apparatus. Ten (10) days after the initial operation, the incidence and severity of any adhesions were evaluated to confirm the efficacy of the HA gel films. Application of the HA gel film reduced the adhesion formation in all treatment groups. This novel HA gel film was effective for reducing postoperative adhesions in the rat model and the efficacy for adhesion ...

This paper describe about technique to retrieve chlorophyll a concentration by using field spectroradiometer data with fluorometer data and the Sea-viewing Wide Field-of-view Sensor (Sea WiFS) data. Spectroradiometer data were coupled with fluorometer data to find out the best suited bands ratio to monitor the chlorophyll a concentration for inland water. Remote sensing reflectance measurements were used to evaluate the performance of several default ocean color chlorophyll algorithms for Sea WiFS data. Using the default chlorophyll algorithms used in TeraScan System (OC2-V2) and SeaDAS (OC4-V4) as the basis of comparison; this study examined the validity of these empirical chlorophyll algorithms with in situ data. Remote sensing reflectance data from spectroradiometer and in situ chlorophyll a data from fluorometer were collected for Lake Abashiri, and SeaWiFS data for Lake Saroma were used. It is shown that the chlorophyll a concentration from fluorometer and reflectance from spectroradiometer lies in exploiting the signal provided by the chlorophyll a red absorption peak near 670nm. Two-band ratio based on a ratio of reflectance 670 and 700nm provided a good correlation for a linear model, compared with blue-green two band ratio.

In magnetic fusion plasmas, particle and energies are lost by the anomalous transport . In order to improve the particle confinement, it is important to figure out the various instabilities in plasmas. Recently, the drift-type instability is suppressed by application of electron cyclotron heating . In GAMMA 10, the plasma is created by plasma guns, and heated and sustained by using ion cyclotron heating (ICH) systems. The x-axis and y-axis are defined as vertical and horizontal directions, respectively. They are perpendicular to z-axis which is parallel to magnetic field line. The mid-plane of GAMMA 10 is z = 0 cm. The ion and electron confinement potentials are produced by using plug/barrier-electron cyclotron heating (P/B-ECH) at both sides of main confinement region, respectively. Plasma potential at main confinement region is measured by GNBP system . The fluctuation of the plasma potential and the fluctuation of electron density can be estimated by using GNBP . In GAMMA 10, the flute-type fluctuation is observed during application of P/B-ECH periods. With the confinement potential formation by ECH, electron line density and stored energy (diamagnetism) increase at first. However, the fluctuation of electron line density increases gradually and the electron line density starts decreasing phase. At the same time, diamagnetism starts decreasing phase. When the electron line density and stored energy are decreasing, the fluctuations of plasma potential and electron density are also increasing quickly. With the Fast Fourier Transform (FFT) analysis, this fluctuation is mainly observed at frequency peak of about 5 kHz in the core plasma. In the edge plasma, the fluctuation with the same frequency peak is observed by the electrostatic probes (ESPs). Moreover this fluctuation’s rotation is anti-clockwise and has no wave number along the magnetic field lines. From these results, we concluded that this fluctuation was caused by flute-type instability. The radial particle flux is estimated by the potential fluctuation, electron density fluctuation and phase difference between potential fluctuation and electron density fluctuation also increase. We thought that this fluctuation has the relation to the reduction of electron line density and stored energy. In this paper, we show the results of the potential fluctuation measurements by using GNBP and electrostatic probes during the P/B-ECH periods. The fluctuations of frequency peak of about 5 kHz are observed by GNBP and ESPs. Then, we discuss the characteristics of these fluctuations.

The bioavailability of magnesium from Wakame and Hijiki, and the effects of alginic acid on absorption of dietary magnesium were examined in five groups of rats fed either control, Wakame, Hijiki, AW (containing the same amount of alginate as in the Wakame) and AH (containing the same amount of alginate as in the Hijiki) diets, and animals fed a low magnesium diet (LMg) (twentieth amount of magnesium in the original mineral mixtures as the control). Food intake and body weight gain were decreased by adding sodium alginate to the diets. A large amount of calcium accumulated only in the kidneys of the rats fed the LMg diet. Serum magnesium concentration decreased only in the LMg group. The magnesium content in the defatted left femurs did not differ between the control and Wakame fed animals and also among the animals eating Wakame, Hijiki and AW diets. The breaking force of the right femurs did not differ among all the groups except the LMg group. The ratio of apparent magnesium absorption (%) of the control, LMg, Wakame, Hijiki, AW and AH groups was 82.2, 72.7, 66.9, 50.8, 69.3 and 54.2 in the first experimental period, and was 75.3, 52.1, 57.7, 46.9, 62.6 and 60.5 in the second experimental period, respectively. It was clear that the bioavailability of magnesium in the Wakame fed rats was higher than in those eating the Hijiki. Large amounts of sodium alginate lowered magnesium absorption from the diet.

This paper proposes a dynamic equation of state for the partially frozen zone between the freezing front and the ice-lens forming front, i.e. the so-called frozen fringe, in a one-dimensionally freezing porous medium saturated with liquid. The dynamic equation of state is derived from an enthalpy balance of the liquid flow in the frozen fringe, and it can be used to quantify the segregation ratio, which represents the segregating volume in the unit volume of a porous medium for a unit time. In addition, the study has clarified that the frozen fringe consists of two zones, namely a sub-cooled zone including the ice-lens forming front where segregation occurs, and an equilibrium zone including the freezing front where in-situ freeze occurs. In the sub-cooled zone, the segregation produces an expansion strain, which was observed by a frost heave experiment. Thus the proposed theory is qualitatively verified by the experimental results.

Existence of the plug potential (PP) bounce ion is quite essential for effective improvement of axial confinement in the tandem mirror, which is bounced by the confining potential hill. We paid attention to the neutral particles changed from the bounce ions through the charge exchange process and measured simultaneously both energy and emergence angle of the neutral particles by use of a charge exchange neutral particle analyzer for measuring bounce ions located near the inner mirror throat (IMT) of the plug barrier cell. We detected successfully the bounce ions during confining potential formation and assigned the bounce ions to the PP bounce ion and the OMT bounce ion which is bounced near the outer mirror throat (OMT) of the plug/barrier cell. The trajectories of the PP bounce ion were calculated, and it was found that the confinement of the PP bounce ion was sensitive to the radial profile of the confining potential in relation to the radial transport.

The radial particle flux induced by the fluctuation is measured by a Gold Neutral Beam Probe. Then the transient transport phenomenon induced by the fluctuation is investigated in the tandem mirror GAMMA 10. When the drift wave is excited at the central cell, the density near the center is reduced and the divergence of the flux becomes similar to the time derivative of the electron density. It shows that the density reduction is caused by the flux induced by the drift wave. After the density reduction, the drift wave is saturated and comes to the steady state because the density reduction accompanies the reduction of density gradient. Therefore, the transport phenomenon accompanying the growth and saturation of the drift wave is observed experimentally. In the steady state, the phase difference obeys the boltzman relation including the electron non-adiabatic term.

In order to extensively and simultaneously analyze frequencies of fluctuations of the end-loss ion current, we prepared three types of analog-to-digital converters (ADC) whose sampling frequencies are 62.5 kHz, 333 kHz and 64 MHz, respectively. The low and intermediate frequency ADCs have 20 channels. The high frequency ADC has a single channel and analyzes the summed signal of the MCP detector. We observed the fluctuations of Alfven ion cyclotron (AIC) mode and the beat phenomenon appeared in the end-loss ion current. On the energy distribution functions of the end-loss ion, we have already observed the gentle humps. We found the relation between the gentle humps and the AIC waves observed in the end-loss ion current, and confirmed by the pitch angle analysis of the beat fluctuation that the AIC waves significantly influenced the trapped ion to transport into the loss region.

An application of electron-cyclotron heating with an off-axis resonance location produces a cylindrical layer with energetic electrons and facilitates the formation for a profile of plasma rotation...

The effects of the plasma-confining potentials and the associated radially sheared electric fields on the central-cell electron energy confinement are theoretically and experimentally investigated in the GAMMA 10 tandem mirror. In particular, the scaling of the central-cell electron temperatures with electron-confining potentials is studied on the basis of the local energy-balance equation. The obtained theoretical scaling of electron temperatures with electron-confining potentials is then compared with the experimentally observed relation between these two parameters. Recently, by the use of new 0.5-MW level gyrotrons in the plug region, four-time progress in the formation of the ion-confining potential Φ c including a new record of 3 kV has been achieved in a hot-ion mode having bulk-ion temperature T i = several keV. In the hot-ion mode, intermittent vortex-like turbulent structures are observed in the case without the gyrotron injections; in this case, radially produced weak shear ofelectric fields dE r /dr and appreciable transverse losses are observed. However, during the application of electron-cyclotron heatings, the associated potential rise produces a stronger shear in the central cell (dE r /dr = several 10 kV/m 2 ) resulting in the disappearance of such intermittent turbulent vortices with plasma confinement improvement. In order to investigate the effect of the radially sheared electric fields on the electron energy confinement, the radial profiles of the thermal diffusivity are derived from the local power-balance analysis by the use of the data from the following various diagnostics in the above-described hot-ion mode. The obtained radial profiles of radial electric field and thermal diffusivity imply that the reduction of the thermal diffusivity is associated with the radially produced strong shear of electric fields.

An inner mirror throat of the plug/barrier cell is one of the noticeable locations in the tandem mirror GAMMA10, because the location is the most suitable for a measurement of the ions bounced by the plug potential, which are essential for the tandem mirror confinement. A lithium beam probe was designed as a main part of the diagnostic system to measure the radial profiles of the electron and neutral particle density at the inner mirror throat. A neutral lithium beam is injected into the plasma and the light emitted from the beam is detected. We estimated the upper limit of the plasma density measurable by the lithium beam probe and discussed validity of the reconstruction for various types of radial profiles. We adopted, at first, a Gaussian type of radial profile of the density with the radius of 2.5 cm for the estimation of the upper limit of the density. It was found that the profile reconstruction was carried out well up to the peak density of 5 × 10 13 cm -3 , and also well even in the non-axisymmetric radial profile. This method is quite appropriate for the measurement of the density profile at the inner mirror throat.

A dynamic equation of state at the solid-liquid interface for a lipuid-saturated "solid-liquid-porous media" system has been derived from a thermodynamic study modeling simultaneous heat and mass transfer through purous media from the liquid supply front to the solid-liquid interface. This is the first step in building a mathematical model which macroscopically describes a freezing expansion phenomenon with mass transfer in saturated porous media. It has been revealed that the derived dynamic equation of state generalizes the so-called generalized Clausius-Clapeyron equation, i.e.the static equation of state for porous media without mass transfer, and that mechanical energy produced at the solid-liquid interface is equal to mechanical energy dissipation due to the mass transfer.

An experimental study has verified the dynamic equation of state derived from a thermodynamic model representing simultaneous heat and mass transfer from the liquid supply front to the solid-liquid interface in a liquid saturated porous medium. Measurement of pore liquid pressure at the solid-liquid interface fixed on the top surface of an Ohya-tuff specimen (the porous medium) enabled us to experimentally verify the relationship between temperature, pore liquid pressure and solid pressure at the interface, and liquid supply pressure. This experimental method was established by re-verifying the so-called Clausius-Clapeyron equation (GCCE), the static equation for a porous medium without liquid flow. This study also clarified the relationship between the dynamic equation of state and the GCCE on the pore liquid pressure-liquid supply pressure plane.

The so-called generalized Clausius-Clapeyron equation (GCCE), i.e., the static equation of state for "solid-liquid-porous media" systems without liquid flow through the pores, has been experimentally examined by measuring the pore liquid pressure at the solid-liquid interface, in order to verify the accuracy of our method for measuring the unfrozen pore liquid pressure. Several series of experiments were carried out using water-saturated Ohya-tuff as a porous medium specimen which was cooled from the top down. In these experiments the solid-liquid interface was always fixed on the top surface of the specimen. The experimental results imply that the measurement method should be useful for determining the relative value of the unfrozen pore liquid pressure.

A dynamic equation of state at the solid-liquid interface for a liquid-saturated "solid-liquid porous media" system has been derived from a thermodynamic study modeling simultaneous heat and mass transfer through porous media from the liquid supply front to the solid-liquid interface, as the very first step in building a mathematical model which may macroscopically describe a freezing expansion phenomenon with mass transfer in saturated porous media. It has been revealed that the derived dynamic equation of state generalizes the so-called generalized Clausius-Clapeyron equation, i.e. the static equation of state for porous media without mass transfer, and that mechanical energy produced at the solid-liquid interface is equal to mechanical energy dissipation due to the mass transfer.

A method for the measurement of the radial flux induced by the electrostatic fluctuations was developed by use of gold neutral beam probes (GNBP). Beam probes were useful devices for the measurement of density and the potential fluctuations in core plasma. The drift wave measured by a GNBP was growing with the finite phase difference between the density and the potential fluctuation. It was found that using the GNBP, the measured drift wave caused the density and the potential profile to be relaxed through the radial particle flux. Since the phase difference of the electrostatic fluctuations would cause the radial flux, the measurement of the phase difference had been one of the key parameter for the radial confinement.

To clarify whether expression of Epstein-Barr virus(EBV) nuclear antigen 2 (EBNA2) correlates with sensitivity to ionizing radiation, we tested EBNA2-transformed rat fibroblast clones for their radiosensitivity to X-rays. These transformed clones reproducibly generated tumors in mice. X-irradiation suppressed the growth of the tumors, and irradiated mice survived longer than non-irradiated ones. In contrast, tumors formed by activated H-ras or E6-E7 genes of human papillomavirus type 16 (HPV16) were strongly resistant to the same dose of X-irradiation. In in vitro culture, these EBNA2-expressing clones also showed higher radiosensitivity than cell lines transformed by activated H-ras and E6E7 genes. The averaged D(o) of EBNA2-expressing clones was 2.3 times lower than that of non-expressing and control clones. These results suggest that expression of EBNA2 is responsible for the radiosensitivity.

The eutrophication and the increase of phytoplankton occur at the many lakes polluted with inorganic and organic matter all over the world. The water quality at lake Abashiri, in which the water quality accidents called as “Aoko” and “Aoshio” in Japanease have often happend, have been simulated numericaly by using “Soumiya” model. In order to analyze numericaly the basic relationship between phytoplankton and zooplankton, the trajector of solution on the phytoplankton-zooplankton phase plane for Lotka-Volterra equation was used. It was shown that phytoplankton could be decreased largely by increasing zooplankton in the period of increasing phytoplankton.

The beam deflection coefficients to the magnetic field fluctuation using a gold neutral beam probe was examined by numerical simulations. The beam deflection parallel to the magnetic field line was mainly caused by the azimuthal component of the magnetic field fluctuation in a case of the beam passing through the plasma center; on the other hand, the beam passing through the plasma edge was deflected by the radial component of the magnetic field fluctuation because the radial and azimuthal velocity components of the beam depend on the injection angle into the plasma. Then, the coefficients could be described as being the function of the injection angle which indicated the radial position of the ionization point and the measured point. As a result of numerical simulation, the coefficients were estimated to be 0.1 and 1.3 for the radial and the azimuthal components of the magnetic field fluctuation in the case of the beam passing through the plasma center. We also estimated the potential effects on the beam...

Existence of the bounced ion by the plug potential (PP) bounce ion is essential in order to improve the ion confinement in the tandem mirror. The trajectories of the PP bounce ion were calculated on the assumption that the equipotential surface was slightly deviated from the equilibrium state, and it was found that the radial electric field affected the radial transport of the bounce ion. A charge exchange neutral particle analyzer was located at the inner mirror throat region as a bounce ion measurement device. The energy distribution function of the bounce ion was measured using the device, and compared with the energy distribution function of the end-loss ion.

An improved gold neutral beam probe system has been developed in order to measure both the potential profile and the electron density profile simultaneously at the central cell of the tandem mirror GAMMA10. A gold film detector was also developed in order to measure the plasma density profile. The yield curves of secondary electrons were measured as a function of the incident angle and electron energy using both the gold neutral beam and ultraviolet ray injection. Time evolution of the plasma line density was measured by adjusting the incident angle and adding a beam chopping method. The result is in good agreement in comparison with the line density measured using a microwave interferometer. It was found that this film detector is very useful for simultaneous measurements of the electrostatic potential and plasma density.