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In this paper, normal zone in a REBCO single-pancake coil induced by quenches in a low-temperature superconducting outsert coil is investigated in both experimental and numerical methods to discuss the quench protection of REBCO coils. The normal zone is experimentally clarified by measuring a partial voltage in the REBCO coil at temperatures from 30 K to 50 K during quenches of the outsert coil charging 5 T. Using practical fittings for the physical properties of the components of the REBCO coil in ranges of 0-5 T and 10-77 K, the numerical results have good agreement with the experimental results. The simulation reveals the heating distribution with initial temperatures from 10 K to 65 K, which indicates that the maximum temperature in a hot spot becomes higher for the lower initial temperature. Unexpectedly, the temperature distribution becomes rather homogeneous with an initial temperature of 65 K. It suggests that the hot spot at higher temperature has a lower risk of burning out. Finally, possible coil protections are discussed as the operation at the high temperature or the quench heater method to keep the REBCO coil at high temperature when a hot spot appears.

To assess the correlation of renal volume measured on CT with aortic contrast enhancement on the hepatic arterial phase of dynamic CT, 64 consecutive patients (34 men, 30 women) were retrospectively examined. Renal volumes were measured on CT. The aortic contrast enhancement was inversely correlated with renal medullary volume (r = -0.52, p 0.0001), and renal cortical volume (r = -0.3, p = 0.02). Renal volume may have inverse correlation with aortic contrast enhancement on the hepatic arterial phase of dynamic CT. This might call for adjustment of contrast material dose based in part on renal volume in the future.

Purpose: To evaluate the speed and precision of split renal volume (SRV) measurement (SRV), which is the ratio of unilateral renal volume to bilateral renal volume, using a newly developed software for computed tomographic (CT) volumetry and to investigate the usefulness of SRV for the estimation of split renal function (SRF) in kidney donors. Method: Both dynamic CT and renal scintigraphy in 28 adult potential living renal donors were the subjects of this study. We calculated SRV using the newly developed volumetric software built into a PACS viewer (n-SRV), and compared it with SRV calculated using a conventional workstation, ZIOSOFT (z-SRV). The correlation with split renal function (SRF) using 99mTc-DMSA scintigraphy was also investigated. Results: The time required for volumetry of bilateral kidneys with the newly developed software (16.7 ± 3.9 sec) was significantly shorter than that of the workstation (102.6 ± 38.9 sec, p < 0.0001). The results of n-SRV (49.7 ± 4.0%) were highly consistent with those of z-SRV (49.9 ± 3.6%), with a mean discrepancy of 0.12 ± 0.84%. The SRF also agreed well with the n-SRV, with a mean discrepancy of 0.25 ± 1.65%. The dominant side determined by SRF and n-SRV showed agreement in 26 of 28 cases (92.9%). Conclusion: The newly developed software for CT volumetry was more rapid than the conventional workstation volumetry and just as accurate, and was suggested to be useful for the estimation of SRF and thus the dominant side in kidney donors.

We investigated the attractiveness of a synthetic form of the pheromone of the soybean stink bug, Piezodorus hybneri (Gmelin), under field conditions, and compared it with that of (E)-2-hexenyl (E)-2-hexenoate, a pheromone component of a competitor, Riptortus pedestris (Fabricius). Many adult stink bugs were attracted to traps baited with 100 mg of the synthetic pheromone (1: 1: one mixture of β-sesquiphellandrene, (R)-15-hexadecanolide, and methyl (Z)-8-hexadecenoate), but few were attracted to 1 or 10 mg. More than twice as many females as males were attracted to this male-produced pheromone. None of the individual pheromone components (30 mg) attracted conspecifics. In summer (June-July), when field P. hybneri were not in diapause, (E)-2-hexenyl (E)-2-hexenoate was more attractive to P. hybneri than the synthetic pheromone. The sex ratio of the adults attracted to the synthetic pheromone was highly female-biased, yet almost equal numbers of both sexes were attracted to (E)-2-hexenyl (E)-2-hexenoate. Most females attracted to both attractants were mated and had mature ovaries. However, adults attracted to (E)-2-hexenyl (E)-2-hexenoate were likely to have less food in their stomach than those attracted to the synthetic pheromone. In late autumn (October-November), when the bugs were in reproductive diapause, both attractants attracted many sexually immature female and male adults that had well-developed fat body. The synthetic pheromone also attracted a large number of conspecific nymphs. These results suggest that P. hybneri pheromone and R. pedestris pheromone component, respectively, have different functions for P. hybneri. The male-produced pheromone system of P. hybneri seems to be sex-related but to have other roles.

The chronic toxicity of enzymatically decomposed rutin, which consists mainly of isoquercitrin, was evaluated in male and female Wistar rats with dietary administration at concentrations of 0%, 0.04%, 0.2%, 1% and 5% for 52 weeks. No toxicological findings were found in the mortality, body weights, food consumption, hematology, clinical biochemistry or organ weights in either sex. Obvious clinical signs were chromaturia that could be attributed to the color of test substance in the 5% groups of both sexes. Coloration of the urine collected over 24h in the 1% and 5% groups of both sexes was noted. Increased daily urinary calcium excretion was observed in the 5% groups of both sexes and an increase in urinary calcium concentration was observed in the male 5% group. On histopathological examination, incidences of mineralization, inflammatory cell debris, inflammatory cell infiltration and/or transitional cell hyperplasia in the renal pelvis were increased in the 5% male group, whereas treated females showed no apparent difference in these incidences. Based on the above findings, the no observed adverse effect level (NOAEL) was estimated to be 1% in both sexes (542.4 mg/kg body weight/day for males and 674.0mg/kg body--weight/day for females).

We report a 49-year-old woman who developed lobular glomerulonephritis with prevalent deposition of material positive for IgG, C1q and lambda light chain, but which was not stained by Congo red. Glomeruli revealed massive electron-dense deposits with a microlamellar structure in the mesangial matrix and peripheral capillary loops. Clinically, the patient had nephrotic syndrome, microhematuria and hypertension. No Bence-Jones protein or cryoglobulin was found in the urine or serum. Anti-DNA antibody was positive, but systemic lupus erythematosus (SLE) was ruled out by repeated serological examinations. Immunoelectrophoresis of blood and urine revealed increased IgG-lambda paraprotein, but no free light chains were found. We reviewed 54 cases reported in the literature, which showed organized crystalline structures on ultrastructural examination, but were unassociated with amyloidosis, SLE, cryoglobulinemia or multiple myeloma. The present patient is the first reported to have exhibited a combination of glomerulonephritis with organized deposits, monoclonal IgG lambda paraproteinemia, and the presence of anti-DNA antibody.

Single photon emission with high degree of circular polarization (DCP) from a positively charged exciton (trion) state in a single quantum dot (QD) is demonstrated under zero magnetic field. Obtained high DCP as large as 0.6 is a clear manifestation of highly effective mutual polarization conversion between single photon and single electron spin. This finding also reveals that the spin relaxation is strongly suppressed during capture and thermalization processes and also in trion ground states in a quantum dot. Moreover, exciton charging state control is shown to be possible by modifying the electron capture probability through the excitation energy tuning, which leads to an exclusive formation of the positive trion in a QD.

Origin of sharp photoluminescence lines observed from an InAlAs quantum dot was identified with the measurements of excitation-power dependences and polarization correlations, together with photon correlation measurements. Single photon emission with high degree of circular polarization (DCP) up to 60% was observed from a positively charged exciton (trion) state in the single quantum dot under non-resonant excitation at zero magnetic field.

In a single self-assembled InAlAs quantum dot, we report the nonlinearity of nuclear spin polarization by optical pumping. Increasing (or decreasing) the excitation power at a particular excitation polarization, nuclear spin polarization shows the abrupt jump (or drop) and a clear hysteresis loop. In addition, the degree of circular polarization of positively charged exciton also exhibits similar bistable behavior and the hysteretic operation has the precise synchronization with the nuclear spin polarization. It suggests that an electron in the positively charged exciton plays a main role to create the abrupt change of the nuclear spin polarization in the observed quantum dot. This abrupt change reveals the sign and magnitude of the electron g -factors in z -direction and can be explained by using a simple model calculation. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Progetto CARG - ISPRA, Note illustrative del Foglio 590 - Taurianova

Nuclear magnetic resonance on oriented nuclei (NMR-ON) on Sc isotopes (A=44, 44 m, 46, 47) in Fe were performed. Using the known magnetic moments the magnetic hyperfine fields were determined. The hyperfine anomalies of various Sc were deduced; 44Δ47=0.0 (12) %, 44mΔ47=1.2 (4) %, 46Δ47=2.7 (8) %. The measured hyperfine anomalies are briefly discussed based on the shell model.

We investigated optical pumping of nuclear spin polarizations in a single self-assembled In0.75Al0.25As/Al0.3Ga0.7As quantum dot. The nuclear spin polarization exhibits the abrupt jump and hysteresis in the excitation power dependence at a particular excitation polarization. Measurement of circular polarization rate of the photoluminescence reveals that the abrupt change of the nuclear spin polarization is created mainly by the spin flip-flop process between nuclei and an electron of a positive charged exciton in this single quantum dot. Model calculation explains well the experimentally observed bistable behavior in InAlAs quantum dot. By using this abrupt change, the sign and magnitude of electron and hole g-factors in z-direction are verified.

We study the exciton states of vertically coupled InAlAs/AlGaAs self-assembled quantum dot (QD) pairs which were designed to have different wetting-layer edges in two QD layers. From a single QD pair, micro-photoluminescence demonstrates four exciton s levels as a result of interdot coupling. Consistent with theory, such a level can be split into four sub-levels. In general, 2-fold splitting is exhibited by the doublet under magnetic field. The doublet is of near-circular polarization in one side but of near-linear polarization in the other side. This abnormal behavior might be understood by heavy hole–light hole mixing. The other 2-fold splitting is observed by photoluminescence excitation measurement without magnetic field. This splitting is suggested resulting from the spatial asymmetry of the coupled QD pair. It is possible that these two split states are robust against magnetic field, and are selectively excited by using pump energy associated with different wetting layers.

Nonresonant carrier tunneling has been studied as a function of temperature in GaAs/AlGaAs double quantum wells (DQWs). Time-resolved pump and probe reflectance measurements allow the direct observation of tunneling at any temperature between 15 K and room temperature. We found that for two DQWs with different barrier thicknesses, the tunneling time abruptly decreases above a critical temperature while it remains almost constant below the critical temperature. This critical temperature is shown to correspond to the exciton binding energy. Rate equation analysis explains this behavior as the thermalization of excitons into free electrons that have a faster tunneling time than excitons.

We report optical pumpingof nuclear spinpolarizationinasingle self-assembledIn0.75Al0.25As/Al0.3Ga0.7As quantum dot where the exciton has a fine structure. Through the change of state mixing that is induced by the anisotropic exchange interaction and the applied magnetic field, the relationship between the magnitude of the Overhauser shift and the optically injected electron spin polarization is discussed. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

We have investigated the influence of postgrowth thermal annealing on the optical properties of InAs/GaAs self-assembled quantum dots. Upon annealing, the emission from InAs QDs shifts toward higher energies with a narrowing of the photoluminescence spectra of QD ensemble. The time-integrated PL spectra show also the nonradiative recombination rate does not increase by annealing process. In addition, from the timeresolved PL, the exciton radiative recombination rate increases with increasing the annealing temperature and agrees well with the atomic-like radiative recombination. These results indicate that interdiffusion of Ga and In atoms into and out of the QDs leads to an increase of the average dot size and concurrently a decrease in the confinement potentials of the QDs preserving their optical quality and zero-dimensional density of states after interdiffusion in the studied annealing temperature range. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Triggered single-photon generation from InAlAs quantum dot (QD) was demonstrated for the first time. Emitted photon energy coincides with high detection efficiency range of Si single-photon detectors, which is highly suitable for free-space communication. Single-QD spectroscopy and crossed photon correlation measurements unambiguously revealed that several emitting lines observed in a single mesa structure originated from the identical QD, and two temporary competing decay processes associated with neutral states and charged states were identified. Presence of the competing process is also inferred from an analysis of steady-state photoluminescence intensities. Formation process of charged exciton in QD is also discussed.

Photon emission with nonclassical photon statistics is discussed with a single InAlAs quantum dot. The deterministic single-photon generation in which the emitted photon wavelength matches well to the highly sensitive wavelength region of highly efficient, low-noise Si-single-photon detectors and also to an atmospheric transmission window is demonstrated. Competing transition processes between neutral and charged exciton species originating from an exclusive formation in the same single quantum dot are clarified. It was found that suppressing the charged exciton formation is possible by a quasi-resonant excitation for a deterministic monochromatic single-photon generation. Polarization-dependent photoluminescence spectroscopy clearly indicates the preservation of photon polarizations between photons emitted by biexciton/exciton recombinations. Furthermore, the deterministic polarization-correlated photon pair generation with biexciton-exciton cascaded transition occurring in a single quantum dot is directly confirmed by the polarized second-order photon correlation measurements. This indicates a longer polarization flip time than the exciton lifetime, which is an essential requirement for the deterministic Einstein-Podolsky-Rosen photon pair generation under the present biexciton-exciton cascaded transition scheme.

Microstructural selection during the directional solidification of binary TiAl alloys grown from Ti–43Al–3Si (at.%) seeds was examined. By using a seed crystal, the high-temperature hexagonal close packed α-phase can be correctly oriented so that an aligned lamellar TiAl/Ti3Al microstructure results from the subsequent solid-state transformations upon cooling. From the equilibrium phase diagram, primary body-centered cubic β-phase solidification is expected in the compositional range for which the binary TiAl alloys were successfully seeded. Thus successful crystal growth of TiAl was found to be dependent upon the undercooling necessary for β nucleation. From these data, a microstructural selection map for the seeded growth of the α-phase was constructed and used to predict the compositional range for seeding TiAl alloys grown in CaO crucibles. The compositional range of the seeding criterion was then extended to multicomponent alloys by using an equivalent-Al concept to predict the shift in the liquidus surface for primary α and β solidification.

Two types of improved core confinement were observed during centrally focused electron cyclotron heating (ECH) into plasmas sustained by counter (CNTR) and Co neutral beam injections (NBI) in the Large Helical Device. The CNTR NBI plasma displayed transition phenomena to the high-electron-temperature state and had a clear electron internal transport barrier, while the Co NBI plasma did not show a clear transition or an ECH power threshold but showed broad high temperature profiles with moderate temperature gradient. This indicated that the Co NBI plasma with additional ECH also had an improved core confinement. The electron heat transport characteristics of these plasmas were directly investigated using heat pulse propagation excited by modulated ECH. These effects appear to be related to the m/n = 2/1 rational surface or the island induced by NBI beam-driven current.

Characteristics of MHD instabilities and their impacts on plasma confinement are studied in current free plasmas of the Large Helical Device. Spontaneous L?H transition is often observed in high beta plasmas close to 2% at low toroidal fields (Bt ? 0.75?T). The stored energy starts to rise rapidly just after the transition accompanying the clear rise in the electron density but quickly saturates due to the growth of the m = 2/n = 3 mode (m and n: poloidal and toroidal mode numbers), the rational surface of which is located in the edge barrier region, and edge localized mode (ELM) like activities having fairly small amplitude but high repetition frequency. Even in low beta plasmas without L?H transitions, ELM-like activities are sometimes induced in high performance plasmas with a steep edge pressure gradient and transiently reduce the stored energy up to 10%. Energetic ion driven MHD modes such as Alfv?n eigenmodes (AEs) are studied in a very wide range of characteristic parameters (the averaged beta of energetic ions, ?b?, and the ratio of energetic ion velocity to the Alfv?n velocity, Vb?/VA), of which range includes all tokamak data. In addition to the observation of toroidicity induced AEs (TAEs), coherent magnetic fluctuations of helicity induced AEs (HAEs) have been detected for the first time in NBI heated plasmas. The transition of a core-localized TAE to a global AE (GAE) is also observed in a discharge with temporal evolution of the rotational transform profile, having a similarity to the phenomenon observed in a reversed shear tokamak. At low magnetic fields, bursting TAEs transiently induce a significant loss of energetic ions, up to 40% of injected beams, but on the other hand play an important role in triggering the formation of transport barriers in the core and edge regions.

Standard diagnostics for fundamental plasma parameters and for plasma physics are routinely utilized for daily operation and physics studies in the large helical device (LHD) with high reliability. Diagnostics for steady-state plasma are under intensive development, especially for Te, ne (yttrium–aluminium garnet (YAG) laser Thomson, CO2 laser polarimeter), data acquisition in steady-state and heat-resistant probes. To clarify the plasma properties of the helical structure, two- or three-dimensional diagnostics are being aggressively developed: tangential cameras (fast SX TV, photon counting CCD, Hα TV); tomography (tangential SX CCD, bolometer); imaging (bolometer, ECE, reflectometer). Divertor and edge physics are important key issues for steady-state operation. Diagnostics for neutral flux (Hα array, Zeeman spectroscopy) and ne (fast scanning probe, Li beam probe, pulsed radar reflectometer) are also in advanced stages of development. In addition to these, advanced diagnostics are being intensively developed in LHD through domestic and international collaborations.

Significant progress has been made with ion cyclotron range of frequencies (ICRF) heating in the Large Helical Device. This is mainly due to better confinement of the helically trapped particles and less accumulation of impurities in the region of the plasma core. During the past two years, ICRF heating power has been increased from 1.35 to 2.7 MW. Various wave-mode tests were carried out using minority-ion heating, second-harmonic heating, slow-wave heating and high-density fast-wave heating at the fundamental cyclotron frequency. This fundamental heating mode extended the plasma density range of effective ICRF heating to a value of 1×1020 m−3. This use of the heating mode was its first successful application in large fusion devices. Using the minority-ion mode gave the best performance, and the stored energy reached 240 kJ using ICRF alone. This was obtained for the inward-shifted magnetic axis configuration. The improvement associated with the axis-shift was common for both bulk plasma and highly accelerated particles. For the minority-ion mode, high-energy ions up to 500 keV were observed by concentrating the heating power near the plasma axis. The confinement properties of high-energy particles were studied for different magnetic axis configurations, using the power-modulation technique. It confirmed that with the inward-shifted configuration the confinement of high-energy particles was better than with the normal configuration. By increasing the distance of the plasma to the vessel wall to about 2 cm, the impurity influx was sufficiently reduced to allow sustainment of the plasma with ICRF heating alone for more than 2 min.

An experiment to measure γ-ray asymmetry A γ with a high precision in neutron-proton radiative capture is under construction at LANSCE. The experiment will determine the weak pion-nucleon coupling constant H π 1 ,, 30% of its predicted value.

Internal transport barriers with respect to electron thermal transport (eITB) were observed in the large helical device, when the electron cyclotron resonance heating (ECH) power was highly localized on the centre of a plasma sustained by neutral beam injection. The eITB is characterized by a high central electron temperature of 6–8 keV with an extremely steep gradient, as high as 55 keV m−1 and a low electron thermal diffusivity within a normalized average radius ρ≈0.3 as well as by the existence of clear thresholds for the ECH power and plasma collisionality.

The behaviour of high-energy ions accelerated by an ion cyclotron range of frequency (ICRF) electric field in the large helical device (LHD) is discussed. A better confinement performance of high-energy ions in the inward-shifted magnetic axis configuration was experimentally verified by measuring their energy spectrum and comparing it with the effective temperature determined by an electron slowing down process. In the standard magnetic axis configuration a saturation of the measured tail temperature was observed as the effective temperature was increased. The ratio between these two quantities is a measure of the quality of transfer efficiency from high-energy ions to a bulk plasma; when this efficiency was compared with Monte Carlo simulations the results agreed fairly well. The ratio of the stored energy of the high-energy ions to that of the bulk plasma was measured using an ICRF heating power modulation method; it was deduced from phase differences between total and bulk plasma stored energies and the modulated ICRF heating power. The measured high energy fraction agreed with that calculated using the injected ICRF heating power, the transfer efficiency determined in the experiment and the confinement scaling of the LHD plasma.

Ion temperature at the plasma centre has been measured from Doppler broadening of Ti XXI (2.61 A) and Ar XVII (3.95 A) x-ray lines using a newly installed crystal spectrometer with CCD detector in ECH, NBI and ICRF plasmas of Large Helical Device (LHD). The ion temperature obtained in a range of 0.6 and 3.5 keV was analysed with electron density and compared with electron temperature. A new parameter range of Ti>Te was found in low-density (ne

Intrinsic impurity behaviour in neutral beam heated LHD long pulse discharges with a discharge duration of 10 s was investigated. Spectroscopic and bolometric measurements showed a remarkable temporal increase of core radiation due to metallic impurities. Central impurity accumulation was found in a narrow plasma density region (e = 1–3×1019 m−3) for both density ramp-up discharges and constant density discharges. In the density ramp-up discharges, high-Z impurities were accumulated in the low-density region and diffused out from the core plasma in the high-density region. The impurity behaviour was compared with neoclassical predictions.

The improvement in the particle confinement of pellet shots on the Large Helical Device (LHD) was found after methane (CH4) mixed hydrogen gas-puff discharges. Only four discharges introducing ∼20 Pa m 3 of CH4 caused the reduction in the radiation loss and the level of metal impurities, together with the enhanced recycling, which is expected as the real time carbonization effect. The decay rate of the electron density was mitigated in the pellet shot after CH4 discharges. Transport analysis shows 60% reduction in the particle transport coefficient at half the averaged minor radius.

The experimentally optimized magnetic field configuration of the Large Helical Device [A. Iiyoshi et al., Nucl. Fusion 39, 1245 (1999)], where the magnetic axis is shifted inward by 15 cm from the early theoretical prediction, reveals 50% better global energy confinement than the prediction of the scaling law. This configuration has been investigated further from the viewpoints of high energy particle confinement and magnetohydrodynamic (MHD) stability. The confinement of high energy ions is improved as expected. The minority heating of ion cyclotron range of frequency was successful and the heating efficiency was improved by the inward shift. The confinement of passing particles by neutral beam injection was also improved under low magnetic field strength, and there could be obtained an almost steady high beta discharge up to 3% in volume average. This was a surprising result because the observed pressure gradient exceeded the Mercier unstable limit. The observed MHD activities became as high as beta but they did not grow enough to deteriorate the confinement of high energy ions or the performance of the bulk plasma, which was still 50% better than the scaling. According to these favorable results, better performance would be expected by increasing the heating power because the neoclassical transport can also be improved there.

By using an appropriately oriented seed from the TiAl–Si system, the TiAl/Ti 3 Al lamellar structure was aligned parallel to the growth direction for ingots having composition of Ti–46Al–0.5Si–0.5X (X=Re, W and Mo) and Ti–47.5Al–0.5Re (at.%). The seeded and directionally solidified quaternary alloys containing either Re, W or Mo exhibit a nice balance of low- and high-temperature mechanical properties. Tensile elongation more than 20% is noted for the W- and Mo-containing alloys. The creep resistance for the three quaternary alloys is more than an order of magnitude better than other relevant TiAl alloys produced by conventional ingot metallurgy methods, with the best creep properties being obtained for the Re-containing alloy. The method to predict alloy compositions appropriate for aligning the lamellar structure of two-phase TiAl alloys of multi-component by directional solidification is proposed based on the assignment of ‘Al-equivalent’ for each of the alloying elements.

Gene therapies may be promising for the treatment of peritoneal fibrosis (PF) in subjects undergoing peritoneal dialysis (PD). However, a method of delivery of treatment genes to the peritoneum is lacking. We attempted to develop an in vivo small interfering RNA (siRNA) delivery system with liposome-based nanoparticles (NPs) to the peritoneum to inhibit PF. Transforming growth factor (TGF)-β1-siRNAs encapsulated in NPs (TGF-β1-siRNAs-NPs) dissolved in PD fluid were injected into the peritoneum of mice with PF three times a week for 2 weeks. TGF-β1-siRNAs-NPs knocked down TGF-β1 expression significantly in the peritoneum and inhibited peritoneal thickening with fibrous changes. TGF-β1-siRNAs-NPs also inhibited the increase of expression of α-smooth muscle actin-positive myofibroblasts. These results suggest that the TGF-β1-siRNA delivery system with NPs described here could be an effective therapeutic option for PF in subjects undergoing PD.

Tensile creep tests were conducted on directionally solidified TiAl alloys to discern the effect of alloying and lamellar orientation. A seeding technique was used to align the TiAl/Ti3Al lamellar structure parallel to the growth direction for alloys of Ti–47Al, Ti–46Al–0.5Si–0.5X (X=Re, W, Mo, and Cr), and Ti–46Al–1.5Mo–0.2C (at.%). Tensile creep tests were performed at 750 °C using applied stresses of 210 and 240 MPa. Aligning the lamellar microstructure greatly enhances the creep resistance which can further be improved by additional alloying.

During the first two years of the LHD experiment the following results have been achieved: (i) higher Te (Te(0) = 4.4 keV at ne = 5.3 × 1018 m-3 and Pabs = 1.8 MW); (ii) higher confinement (τE = 0.3 s, Te(0) = 1.1 keV at ne = 6.5 × 1019 m-3 and Pabs = 2.0 MW); (iii) higher stored energy, Wpdia = 880 kJ at B = 2.75 T. High performance plasmas have been realized in the inward shifted magnetic axis configuration (R = 3.6 m) where helical symmetry is recovered and the particle orbit properties are improved by a trade-off of MHD stability properties due to the appearance of a magnetic hill. Energy confinement was systematically higher than that predicted by the International Stellarator Scaling 95 by up to a factor of 1.6 and was comparable with the ELMy H mode confinement capability in tokamaks. This confinement improvement is attributed to configuration control (inward shift of the magnetic axis) and to the formation of a high edge temperature. The average beta value achieved reached 2.4% at B = 1.3 T, the highest beta value ever obtained in a helical device, and so far no degradation of confinement by MHD phenomena has been observed. The inward shifted configuration has also led to successful ICRF minority ion heating. ICRF powers up to 1.3 MW were reliably injected into the plasma without significant impurity contamination, and a plasma with a stored energy of 200 kJ was sustained for 5 s by ICRF alone. As another important result, long pulse discharges of more than 1 min were successfully achieved separately with an NBI heating of 0.5 MW and with an ICRF heating of 0.85 MW.

The mechanical properties of TiAl-based alloys with lamellar microstructure are extremely anisotropic. However, if the lamellar microstructure can be aligned parallel to the growth direction, the resulting material should possess a good combination of mechanical properties. Unfortunately, simple casting operations often lead to a solidification texture with the lamellar boundaries perpendicular to the heat flow direction. This difficulty can be overcome by directionally solidifying TiAl-based alloys. We have been performing directional solidification experiments with and without using a seeding technique. The current status of directional solidification of TiAl-based alloys is reviewed.

The nuclear magnetic moments of the ground states of ${}^{76}\mathrm{As}$ and ${}^{77}\mathrm{As}$ were measured using nuclear magnetic resonance on oriented nuclei (NMR-ON) by detecting $\ensuremath{\gamma}$ rays and $\ensuremath{\beta}$ rays. The magnetic hyperfine splitting frequencies of ${}^{76}\mathrm{As}\mathrm{Fe}$ and ${}^{77}\mathrm{As}\mathrm{Fe}$ in a zero external magnetic field are 117.99(8) MHz and 225.58(8) MHz, respectively. With the known hyperfine field of ${B}_{\mathrm{hf}}{(}^{75}\mathrm{As}Fe)=34.29(3) \mathrm{T}$ the magnetic moments have been determined as $\ensuremath{\mu}{(}^{76}\mathrm{As}{,2}^{\ensuremath{-}})=(\ensuremath{-})0.9028(10){\ensuremath{\mu}}_{N}$ and $\ensuremath{\mu}{(}^{77}\mathrm{As}{,3/2}^{\ensuremath{-}})=+1.2946(13){\ensuremath{\mu}}_{N}.$ The effective spin-lattice relaxation time for ${}^{76}\mathrm{As}\mathrm{Fe}$ has been measured to be 5.2(8) m and 11.2(16) m at the external magnetic field of 0.2 T and 0.6 T, respectively. The observed magnetic moments are discussed in the framework of the configuration mixing model.

Large abdominal wall defects may require a prosthesis for closure. The aim of our study was to identify the best material for abdominoplasty in pediatric patients. One hundred twenty-eight Wistar KY strain male rats (3 weeks old) were used. All animals underwent celiotomy via a midline skin incision. They were divided into seven groups as follows: the animals in groups 1 through 6 underwent full-thickness abdominal wall excision 3 cm in diameter. The animals in group 1 underwent primary closure. In groups 2 through 6 the defect was closed with prosthetic material. In Group 7, a sham operation was performed. Daily weights were measured. The animals were killed after 3 and 9 weeks. Adhesion scores were assigned for each group. Vicryl mesh resulted in the fewest adhesions and had no effect on weight gain in the developing rats.

A vacuum crystal spectrometer that covers a wavelength range of 1.0–2.5 nm has been developed to observe light (oxygen) and heavy (titanium and iron) impurities for large helical device (LHD) diagnostics. A Johann-type spectrometer (2R = 60 cm and 3 m, RAP crystal, 2d = 2.612 nm) was constructed and installed in a compact helical system (CHS). The O VII resonance line was successfully observed through a thin (3.3 μmt) polypropylene film, although the metallic impurity lines were not seen. In the case of a crystal with 2R = 3 m, however, the spectral resolution λ/Δλ was limited to 440, whereas the replacement by the crystal with 2R = 60 cm improved the resolution to 610. The result is discussed with regard to the quality of the bent crystal.