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Modification of JT-60U to a superconducting device (so called JT-60SA) has been planned to contribute to ITER and DEMO. The NBI system is required to inject D 0 beams of 34 MW for 100 s. The upgraded NBI system for JT-60SA consists of 12 positive-ion-based NBI (P-NBI) units and one negative-ion-based NBI (N-NBI) unit. The injection powers of each P-NBI and N-NBI units are 2 MW at 85 keV and 10 MW at 500 keV, respectively. On JT-60U, the long pulse operations of 30 s at 2 MW and 20 s at 3.2 MW have been achieved on the P-NBI and N-NBI units, respectively. Both units have demonstrated no injection power degradation for long pulse operation. It has been also found that the thermal time constants of the main key components with active cooling, such as the ion source of the present NBI system, are less than ∼20 s. Therefore, the pulse extension up to 100 s is expected to need some modifications mainly the power supply system. In addition, the voltage-holding capability of the negative ion source is required to be improved. The detailed technical design of the NBI system for JT-60SA is presented.

We have developed a 64-channel magnetocardiograph (MCG) system for the diagnosis of heart disease. The MCG is characterized by its display of a unique three-dimensional image of bio-currents flowing inside the human body. The outline of the heart can be displayed without use of MRI. A mobile SQUID-based non-distractive evaluation apparatus was realized by the active shielding technique. The system can offer information from beneath the surface of the specimen by using a saw-wave excitation method. This mobile technology enables us to inspect ferromagnetic materials, whose high magnetic field rules out the use of a conventional SQUID apparatus near them.

Efforts to identify pharmaceuticals to treat heritable metabolic liver diseases have been hampered by the lack of models. However, cells with hepatocyte characteristics can be produced from induced pluripotent stem cells (iPSCs). Here, we have used hepatocyte-like cells generated from homozygous familial hypercholesterolemia (hoFH) iPSCs to identify drugs that can potentially be repurposed to lower serum LDL-C. We found that cardiac glycosides reduce the production of apolipoprotein B (apoB) from human hepatocytes in culture and the serum of avatar mice harboring humanized livers. The drugs act by increasing the turnover of apoB protein. Analyses of patient medical records revealed that the treatment of patients with cardiac glycosides reduced serum LDL-C levels. These studies highlight the effectiveness of using iPSCs to screen for potential treatments for inborn errors of hepatic metabolism and suggest that cardiac glycosides could provide an approach for reducing hepatocyte production of apoB and treating hypercholesterolemia.

It is desired to develop a high-strength high-conductivity material for reinforcing composite superconductors which will be employed in large-scale and/or high-field superconducting magnets in emerging large-scale projects such as fusion magnets, SMES magnets, hybrid magnets, and so on. A review of our decade long study of reinforcing stabilizers, and recent results on CuNb composite wires and high-purity Ta wires are reported. Mechanical and electrical properties are reported for CaO crucible melted and drawn CuNb composite wires and for heavily cold worked high-purity Ta wires. Tensile tests at room temperature show a yield stress of about 556 MPa even after annealing at 750°C for 1 h for CuNb composite wires and 0.2% proof stress of about 666 MPa for the Ta wires. Resistivity at 4.2 K is about 0.25 μ ω cm for CuNb wires and about 0.40 μω cm for the Ta wires, respectively at a field of 15 T. It is concluded that the CuNb composite wires, the high-purity Ta wires and the Al2O3 dispersion-strengthened copper are suitable as a reinforcing stabilizer for conductors of large-scale and/or high-field superconducting magnets.

The Nb/Al composite wires with various average thicknesses of niobium layer, from 43 to 300 nm, were fabricated by the method using aluminum-clad niobium foils as a starting material and the dependency of the critical current density J c on the niobium layer thickness was studied. Even at a thickness of 43 nm, J c gave no tendency for saturation. In contrast, the transition temperature was saturated at about 17K. Although the obtained J c values exceeded the best ones for the Nb/Al composite wires fabricated by the powder metallurgy process and niobium-tube method, they were still far from the results for stoichiometric Nb 3 Al. The J c dependency on the niobium layer thickness was compared with the data in other methods and discussed in detail.

Recent improvements and developmental research on several high field superconducting wires are reviewed. High field characteristics of NbTiHf wires, wound in a 13.08 T superconducting magnet in a 1.8 K pressurized superfluid helium bath, have been studied in detail. Ti-alloyed Nb 3 Sn fm wires prepared by the Nb-tube method showed excellent high field J c -characteristics and were wound in a 16.7 T superconducting magnet. One of these wires was employed in the HOMER facility (a multipurpose superconducting magnet at KfK) and generated 20.15 T, recently. A new process called the clad chip extrusion (CCE) method has been developed for the preparation of superconducting Nb 3 Al wires. Short samples of the CCE processed Nb 3 Al wires showed J c higher than 10 4 A/cm 2 up to 18.8 T at 4.2 K. One of the in-situ processed V 3 Ga short sample wires prepared by an induction melting using a CaO crucible showed J c =10 4 A/cm 2 at 16.2 T and 4.2 K, which will be improved by further optimization of the process and the composition.

A thermal plume occurs above a heat island. This plume affects the real urban climate and the heat island phenomenon. Because of its complexity, a real heat island, from which the thermal plume occurs, is simplified. A simplified heat island is a line heat source. A thermal plume above this simplified heat island was investigated. In general, a thermal plume sways naturally from side to side, and, in most cases, a plume is occurring in a thermally stable stratified fluid. Therefore, a thermal plume with a swaying motion in a thermally stable stratified fluid inside a comparatively large enclosure was formed and experimentally investigated. The thermal plume was observed by flow visualization. The plume temperature was measured, and the statistical analysis was carried out in time series data of the plume temperature. As a result, the fumigation motion of the plume above the simplified heat island with extremely low heat rate is firstly visualized and then clarified by this laboratory experiment. This fumigation behavior clarified in this investigation is quite important in the heat island phenomenon and the urban climatology.

Summary This paper deals with a polishing method of free formed surface. First, the effect of tool oscillation on the characteristics of curved surface polishing is discussed, and then, a polishing method to optimize the tilt angle of curved surface is described. The surface quality polished by a polishing head with tool oscillation is superior to that by a polishing head without tool oscillation, because tool contact area become wider when the tool is oscillated at low speed. The tilt angle of curved surface can be detected m polishing process using the oscillated polishing head, and the curved surface is thus kept horizontal at every polishing point by controlling a tilting table. Consequently, the free formed surface such as moulding die and the aspheric surface of optical element can be easily polished, and scratch free polishing surface and the same polishing removal rate can be obtained at every polishing point.

The magnetoresistance of the weak itinerant-electron ferromagnet Sc3In was measured from 1.5 to 40 K in magnetic fields up to 14 T. The measurements were made on three samples containing 24.1, 24.3 and 24.4 at% In with Curie temperatures at H = 0 of Tc(0) = 5.5, 6.0 and 6.3 K, respectively. By assuming that the characteristic spin-fluctuation temperature is equal to Tc(0), the negative magnetoresistance in Sc3In was systematically and reasonably analyzed in terms of the quenching of spin fluctuations by magnetic fields.

The Hall angle θ in three V samples (RRR = 80, 120, 140) and two Nb samples (RRR = 57, 66) has been measured in the mixed state in order to elucidate the transport properties in the intrinsic type-II superconductors with intermediate purity.

The specific heat and the magnetization have been measured on Nb0.8-Mo0.2 alloy in the temperature range from 1 K to 5 K. The analysis of these data gives the Ginzburg-Landau parameter κ = 4.13 at Tc = 4.28 K. The critical fields, Hc2(0) and Hc(0), have been found to be 5437 Oe and 747 Oe, respectively. This alloy is found to be in the dirty limit of a type-II superconductor. According to the recent theory of Maki, these fundamental parameters together with the electrical resistivity in the normal state determine the type-II behaviors of the transport properties of this alloy with respect to their dependences on temperature and magnetic field. In the gapless region, the flow resistance and the entropy of the vortex motion deduced from Ettingshausen coefficients show their magnitudes and the temperature dependences in good agreement with the prediction of this microscopic theory. In addition the jump in the specific heat at the transition from the mixed state to the normal one has been measured at twelve values of the field up to 4566 Oe. This jump may be explained well in terms of the thermodynamical relation at that transition.

The Hall angle measured on a Nb0.8Mo0.2 alloy is found to be well explained by the recent theory of Maki.

A new type of manostat has been developed, in which a thin-film material is utilized. It is possible to control the liquid He vapour pressure within 0.1 Torr (1.3 × 10 Nm −2 ) in the range between 1 atm (1.01 × 10 5 Nm −2 ) and 4 Torr (5.3 × 10 2 Nm −2 ) by use of a thin polyethylene film sheet.