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A divertor simulation experimental module (D-module) in the tandem mirror GAMMA 10/PDX was used for the study of plasma detachment. In previous studies, it was difficult to measure far-upstream plasma parameters in the D-module, and only electrostatic probes on the target plate were used to perform electron temperature and density measurements. To study the detached plasma structure, a Thomson scattering (TS) system and a microwave interferometer system have been installed to measure the inside plasma parameters of the D-module, and a movable electrostatic probe has been placed at the inlet of the D-module to measure the inlet plasma density and temperature. The TS system in the central cell observed the electron temperature and density of the core plasma simultaneously. These measurements revealed the entire density and temperature structure from the core plasma to the divertor plate. The line average electron density measured by the microwave interferometer showed a rollover behavior during detachment. The results indicated that the ionization region was located around the center of the D-module, and it appears to move upstream along the axis.

The transition of a detached to attached plasma experiment has been performed in GAMMA 10/PDX by applying an additional plasma heating pulse of electron cyclotron heating (ECH). In a plasma detachment experiment, a short pulse (25 ms) of ECH was applied at the east plug-cell to examine the effects of electron heating on the plasma parameters in the D-module. It was found that the ion flux increased significantly during ECH injection. In the ECH injection period, the ion flux increased with the increasing impurity injection, which indicates the impurity ion components are enhanced by ionization in the D-module due to the application of ECH. During ECH injection period, the increase of the ion flux near the corner of the target plate shows a clear dependence on the gas species. The 2D visible emission has been captured by the high-speed camera and a bright emission near the corner of the target has been observed. The spectroscopic measurement in the D-module shows that the impurity ion emission increases remarkably during ECH injection. These results indicate the detached plasma change to the attached state.

Echocardiography offers rapid and cost-effective estimations of left ventricular (LV) mass, but its accuracy in patients with cardiac disease remains unclear. LV mass was measured by M-mode-based linear method and two-dimensional echocardiography (2DE)-based area-length method in pig models and correlation with actual LV weight was assessed. Twenty-six normal, 195 ischemic heart disease (IHD), and 33 non-IHD HF pigs were included. A strong positive linear relationship to the actual LV weight was found with 2DE-based area-length method (r = 0.82, p < 0.001), whereas a moderate relationship was found with M-mode method in the overall population (r = 0.68, p < 0.001). Two correlation coefficients were significantly different (p < 0.001), and were driven mainly by incremental overestimation of LV mass in heavier hearts using the M-mode method. IHD and LV dilation were the factors contributing to overestimation using M-mode method. 2DE-based area-length method provides a better estimation of LV weight in swine models of HF, particularly in those with IHD.

In this paper, the detailed results of the effect of additional plasma heating under the condition of plasma detachment produced in the large tandem mirror GAMMA 10/PDX. In this experiment, the ECH pulse of 150 kW was applied to the upstream region of detached plasmas established by injecting heavy noble gases (Ar, Kr and Xe) and the significant phenomena on detached to attached transition were measured with Langmuir probes, calorimeters, spectrometers and a high-speed camera. In the presentation, detailed behavior of the plasma parameters is described and the effect of ECH is discussed in terms of radiation loss power and ionization and recombination processes. During the plasma detachment experiments by impurity gas seeding, a short pulse (25 ms) of ECH was applied at the east plug/barriercell to examine the effects of ECH on the detached plasma. A brief summary of the outcomes is given below: ECH heating pulse significantly increases the heat flux at the west end-cell, which indicates detached to attached transition phenomena. During ECH injection period, the ion flux also increases with the increasing gas injection. The emission from the impurity ion enhances significantly during ECH injection period. The emission intensity captured with fast camera also shows a clear dependence on the gas throughput of N2 gas. Comparison of the results using light impurities (N2 and Ne) to those by a heavy impurity gas (Ar) indicates that detached plasma with N2 seeding has a certain tolerance for the additional heating. These outcomes also indicate to consider the sustainability of the detached plasma during ELM., The 23rd International Conference on Plasma Surface Interactions in Controlled Fusion Devices (PSI-23)

GAMMA10/PDX のDモジュール内のプラズマに，水素とともに少量の窒素などの不純物ガスを入射し，それらの非接触プラズマ形成に与える影響を調べた．水素と窒素を同時に入射した場合には，電子密度とイオン束の明らかな減少が観測された．他方，ネオンやアルゴンなどの希ガスを水素とともに入射した場合には，電子密度とイオン束の減少は明らかではなかった．この結果は窒素分子が介在した再結合過程が重要であることを示唆している．

This paper describes the characteristics of detached plasma produced by using hydrogen and noble gases together with the progress of high-heat and particle flux generation experiments in the GAMMA 10/PDX end-cell. In the Plasma Research Center, University of Tsukuba, divertor simulation experiments have been started at the end-cell of GAMMA 10/PDX (E-divertor). In the GAMMA 10/PDX end-cell, plasma flow with high temperature (Ti=100–400 eV, Te=30 eV), heat and particle fluxes (>10 MW/m2, >1023/m2s, respectively) have been produced under the high magnetic field (~1T), which cannot be attained by conventional liner devices. We have succeeded in achieving detachment of high temperature plasma equivalent to the SOL plasma of tokamaks in spite of using a linear device with short connection length of magnetic field line. Various gases (N2, Ne, Ar, Xe) are examined to evaluate the effect of radiation cooling against the plasma flow of MW/m2 level in a divertor simulation region and the following results are obtained: i) Xe gas was most effective on electron cooling (down to ~2 eV) and reduction of heat and particle fluxes (1%, 3%, respectively). ii) Ne gas was less effective. On the other hand, iii) N2 gas showed more favourable effects than Ar. The above results are almost consistent with the observation from an absolutely calibrated visible spectrometer viewing the inside of D-module, such as i) stronger emission from Xe I and II, ii) significant molecular visible-emission from N2, etc. Furthermore, in the case with a simultaneous injection of hydrogen and Xe gases, the ion flux was almost fully suppressed, which indicates the existence of molecular activated recombination in D-module. In plasma flow generation experiments, ICRF heating in anchor-cell successfully extended the particle flux up to 3.3ˆ1023 /m2s in the end-cell. Superimposing the ECH pulse (380 kWx5 ms) into the ICRF plasma also succeeded in extending the highest heat flux of ~15 MW/m2, which exceeds the ITER divertor heat load in the steady state. These results will contribute to the progress in detached plasma operation and clarification of radiation cooling mechanism towards the development of the future divertor., 26th IAEA Fusion Energy Conference

Until the early 1990s, Japanese education was widely commended for achieving outstanding outcomes in global comparison. At the same time, it was frequently criticized for failing to cultivate 'individuality' and 'creativity' in students. Wide-ranging education reforms were enacted during the 1990s to remedy these perceived failings. However, as this book argues, the reforms produced a different outcome than intended, contributing to growing disparity in learning motivation and educational aspiration of students from different class backgrounds instead.

BACKGROUND: Recent studies, supported by advances in computer science, have successfully simulated the excitation and repolarization processes of the heart, based on detailed cell models of electrophysiology and implemented with realistic morphology. METHODS: In this study, we extend these approaches to simulate the body surface electrocardiogram (ECG) of specific individuals. Patient-specific finite element models of the heart and torso are created for four patients with various heart diseases, based on clinical data including computer tomography, while the parallel multi-grid method is used to solve the dynamic bi-domain problem. Personalization procedures include demarcation of nonexcitable tissue, allocation of the failing myocyte model of electrophysiology, and modification of the excitation sequence. In particular, the adjustment of QRS morphology requires iterative computations, facilitated by the simultaneous visualization of the propagation of excitation in the heart, average QRS vector in the torso, and 12-lead ECG. RESULTS: In all four cases we obtained reasonable agreement between the simulated and actual ECGs. Furthermore, we also simulated the ECGs of three of the patients under bi-ventricular pacing, and once again successfully reproduced the actual ECG morphologies. Since no further adjustments were made to the heart models in the pacing simulations, the good agreement provides strong support for the validity of the models. CONCLUSIONS: These results not only help us understand the cellular basis of the body surface ECG, but also open the possibility of heart simulation for clinical applications.

The dependence of the resonance position of the central-ECH (c-ECH) on plasma behavior was investigated using a fast camera. When the resonance positions were higher, low frequency fluctuation of∼6kHz was observed and at the same time the diamagnetic signal decreased. Also, the same frequency fluctuation was observed in the potential signal by Au beam probe. On the other hand this low frequency fluctuation was not appeared when the resonance position was seemed to be on the axis of the plasma. These results indicate that the convective ExB drift instabilities may be induced due to the off-axis heating by c-ECH.

A new 28 GHz - 1 MWgyrotron has been developed for ECRH system of GAMMA 10 tandem mirror. To achieve the design target of the new gyrotron, which is 1 MW output for 1 s, the magnetron injection gun (MIG) and cavity were designed in detail with calculation codes. A first tube has been fabricated, and performance test is in progress. The maximum output power of 1.04 MW and the maximum output efficiency of 40.6% were obtained with short pulse operation. However, at the same time, it was confirmed that the output efficiency had decreased with the increase of beam current. This is explained with a decrease, which is a one of issues to develop a higher efficiency gyrotron.

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.

Three Japanese patients with lecithin: cholesterol acyltransferase (LCAT) deficiency, the offspring of a consanguineous marriage, are described. In addition to the Characteristic clinical and laboratory findings of the disease, our patients had hitherto unreported manifestations, namely unconjugated hyperbilirubinemia, peripheral neuropathy and marked hypocholesterolemia. Although the mechanism of the unconjugated hyperbilirubinemia is not clear, the rde of impaired hepatic bilirubin uridine-diphosphate-glucuronyl transferase activity combined with another unknown factor(s) was postulated. Non-random assortment was observed between LCAT deficiency and haptoglobin types, as previously reported. The discovery of Japanese patients with LCAT deficiency indicates that the distribution of this hereditary metabolic disorder is not confined to the Western hemisphere.