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Physics assessments on magnetohydrodynamics equilibrium, neoclassical transport and alpha particle confinement have been carried out for the helical fusion DEMO reactor FFHR-d1, using radial profiles extrapolated from the Large Helical Device. Large Shafranov shift is foreseen in FFHR-d1 due to its high-beta property. This leads to deterioration in neoclassical transport and alpha particle confinement. Plasma position control using vertical magnetic field has been examined and shown to be effective for Shafranov shift mitigation. In particular, in the high-aspect-ratio configuration, it is possible to keep the magnetic surfaces similar to those in vacuum with high central beta of ∼8% by applying a proper vertical magnetic field. As long as the Shafranov shift is mitigated, the neoclassical heat loss can be kept at a level compatible with the alpha heating power. The alpha particle loss can also be kept at a low level if the loss boundary of alpha particles is on the blanket surface and the plasma position control is properly applied. The lost positions of alpha particles are localized around the divertor region that is located behind the blanket in FFHR-d1. [ABSTRACT FROM AUTHOR]

The effect of non-axisymmetric magnetic perturbations and E × B rotation on neoclassical toroidal viscosity (NTV) is investigated using a drift-kinetic δf Monte-Carlo simulation code, FORTEC-3D, and the simulation is benchmarked with an analytic formula which uses bounce-average approximation. Although the δf code agrees with the analytic formula if the E × B velocity is low or the radial position is away from the resonant rational flux surface, a clear difference appears in the radial profile of NTV when the E × B velocity becomes large. A double-peak profile of NTV appears around the resonant rational flux surface only in the δf simulation. The double peak is created as a result of the resonance of E × B drift and passing particle motion. The benchmark result suggests that the precise drift-kinetic simulation, which treats both trapped and passing particle contributions to neoclassical viscosity, is essential for quantitative evaluation of the rotation damping rate by NTV when the E × B rotation is not slow. [ABSTRACT FROM AUTHOR]

A central ion temperature of 7 keV in a neutral beam injection (NBI)-heated plasma and a central-electron temperature of 20 keV in an electron cyclotron resonance heating plasma were achieved in the Large Helical Device (LHD) using an upgraded heating system with a newly installed perpendicular-NB injector and gyrotrons. The values of Ti and Te significantly exceeded 5.6 and 15 keV, obtained in previous experiments, respectively. High-Ti plasma was obtained using a carbon pellet injection and the kinetic-energy confinement improved by a factor of 1.5. Transport analysis of the high-Ti plasmas showed that the ion-thermal diffusivity and the viscosity were reduced after the pellet injection. Dynamic-transport analysis is applied and the transition to the ion-internal-transport barrier and back transition are discussed. [ABSTRACT FROM AUTHOR]

Electrode biasing experiments were carried out in various magnetic configurations on the Large Helical Device (LHD). The transitions of poloidal viscosity, which were accompanied with bifurcation phenomena characterized by a negative resistance in an electrode characteristic, were clearly observed on LHD by the electrode biasing. The critical external driving force required for transition was compared with the local maximum in ion viscosity, and the radial resistivity before the transition also compared with the expected value from a neoclassical theory. The critical driving force increased and the radial resistivity decreased with the major radius of the magnetic axis Rax going outwards. The configuration dependence of the transition condition and the radial resistivity qualitatively agreed with neoclassical theories. The radial electric field and the viscosity were also evaluated by the neoclassical transport code for a non-axisymmetric system, and estimated electrode voltage required for the transition, which was consistent with the experimental results. [ABSTRACT FROM AUTHOR]

A comparative study of energy transport for medium- to high-density discharges in the stellarator-heliotrons TJ-II, W7-AS and LHD is carried out. The specific discharge parameters are chosen to apply a recently concluded benchmarking study of neoclassical (NC) transport coefficients (Beidler et al 2011 Nucl. Fusion 51 076001) to perform this validation study. In contrast to previous experiments at low densities for which electron transport was predominant (Yokoyama et al 2007 Nucl. Fusion 47 1213), the current discharges also exhibit significant ion energy transport. As it affects the energy transport in 3D devices, the ambipolar radial electric field is addressed as well. For the discharges described, ion-root conditions, i.e. a small negative radial electric field were found. The energy transport in the peripheral region cannot be explained by NC theory. Within a 'core region' (r/a < 1/2 ~ 2/3), the predicted NC energy fluxes comply with experimental findings for W7-AS. For TJ-II, compliance in the core region is found for the particle transport and the electron energy transport. For the specific LHD discharges, the core energy transport complied with NC theory except for the electron energy transport in the inward-shifted magnetic configuration. The NC radial electric field tends to agree with experimental results for all devices but is measured to be more negative in the core of both LHD and TJ-II. As a general observation, the energy confinement time approaches the gyro-Bohm-type confinement scaling ISS04 (Yamada et al 2005 Nucl. Fusion 45 1684). This work is carried out within the International Stellarator-Heliotron Profile Database (www.ipp.mpg.de/ISS and http://ishpdb.nifs.ac.jp/index.html). [ABSTRACT FROM AUTHOR]

Three-dimensional effects on plasma flows have been experimentally studied in the large helical device with 3D configurations. Spontaneous toroidal flow without net driving force using the combination of perpendicular neutral beam injection (NBI) heating and balanced tangential NBI heating has been investigated with two magnetic configurations. Co- and counter-directed spontaneous flows have been observed depending on the collisionality. Toroidal flow shear changes the sign at 0.4eff<0.6 between co- and counter-flowing plasmas, where reff is a averaged minor radius. The detailed flow structures have been also examined at the edge region with stochastic magnetic field. A poloidal flow driven by the positive radial electric field has been observed at the open field region just outside of the plasma boundary. At the stochastic region, a shear of poloidal flow has been observed, while no shear of toroidal flow has been observed. The toroidal flow shear changes only in the nested magnetic flux surface region. A difference of density fluctuation property has been observed between co- and counter-flowing plasmas, where toroidal flow shears are formed. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the post-operative outcome of 14 patients 16 knees that were treated operatively with percutaneous drilling (D), screw fixation (S), and lateral retinacular release (LRR) for painful bipartite patella. All patients were male athletes, and were observed for a mean of 25.6 months. The average age of the patients was 14.9 years. The separated form of the bipartite fragment was classified as type II in 3 patients 4 knees, and type III in 12 patients 12 knees according to the Saupe classification. Growth plate was persistent in 11 patients 13 knees. D was performed in 8 patients 8 knees. D + S in 2 patients 3 knees, D + LRR in 3 patients 4 knees, and D + S + LRR in 1 patient 1 knee. Complete bony union of the separated fragment and the patella at final follow up was observed in 5 knees (31.3%), incomplete in 10 knees (61.5%), and non-union in 1 knee (6.3%). The bony union rate was not associated with surgical procedures and the presence of growth plate. Ten patients (71.4%) had returned to full sporting activities; especially all patients (4 patients 5 knees) who were treated with LRR had their pain relieved and returned to their original sporting activities. On the other hand, osteosynthesis such as D and S did not provide good clinical results. We suggest that lateral retinacular tension might influence patellofemoral pain of the bipartite patella and LRR is an effective procedure for painful bipartite patella without mal-alignment and patellar instability. [ABSTRACT FROM AUTHOR]

INTRODUCTION: A rapidly firing or triggered ectopic focus located within a pulmonary vein (PV) or close to the PV ostium could induce atrial fibrillation (AF). The aim of this study was to evaluate the efficacy and safety of a radiofrequency thermal balloon catheter for isolation of the PV from the left atrium (LA). METHODS AND RESULTS: Twenty patients with drug-resistant paroxysmal AF were treated by isolating the superior PVs using an RF thermal balloon catheter. Using a transseptal approach, the balloon, which had an inflated diameter 5 to 10 mm larger than that of the PV ostium, was wedged at the LA-PV junction. It was heated by a very-high-frequency current (13.56 MHZ) applied to the coil electrode inside the balloon for 2 to 3 minutes, and the procedure was repeated up to four times. The balloon center temperature was maintained at 60 degrees to 75 degrees C by regulating generator output. Successful PV isolation was achieved in 19 of the 20 left superior PVs and in all 20 of the right superior PVs and was associated with a decrease in amplitude of the ostial potentials. Total procedure time was 1.8 +/- 0.5 hours, which included 22 +/- 7 minutes of fluoroscopy time. After a follow-up period of 8.1 +/- 0.8 months, 17 patients were free from AF, with 10 not taking any antiarrhythmic drugs and 7 taking the same antiarrhythmic agent as before ablation. Electron beam computed tomography revealed no complications, such as PV stenosis at ablation sites. CONCLUSION: The PV and its ostial region can be safely and quickly isolated from the LA by circumferential ablation around the PV ostia using a radiofrequency thermal balloon catheter for treatment of AF. [ABSTRACT FROM AUTHOR]

Liquid wall concept has a significant place in the Advanced Power Extraction (APEX) study as a part of the US program on Nuclear Fusion. In the present paper, different approaches currently developed for modeling liquid wall magnetohydrodynamics and heat transfer in APEX have been presented. Turbulent flows of low-conductivity liquids, such as molten salts (Flibe), are analyzed using a two-equation turbulence model and Direct Numerical Simulation. The analysis of liquid metal flows under a strong reactor magnetic field is based on the magnetohydrodynamic equations for laminar flows. [ABSTRACT FROM AUTHOR]

Provides information on a study which examined receptor subtypes and ionic mechanisms involved in the noradrenergic modulation of GABAergic synapses in the cerebellar cortex. Materials and methods; Results; Discussion.

Presents several pictures on visualization study published on the 'Journal of Visualization.' Simulation of flow structure around two cylinders; Generation of vortex and breaking processes in an impinging round jet; Use of microelectromechnical systems to control turbulent flow.

Advanced glycation endproduct (AGE) accumulation in extracellular matrix proteins has been demonstrated in diabetic patients with a significant correlation with the severity of diabetic complications. AGE accumulation induces matrix protein cross-link formation, resulting in an increased stiffness of matrix fibres and the reduction of the susceptibility of matrix proteins to proteolytic degradation. We examined whether glycation-induced collagen cross-linking may affect vascular endothelial cell behaviours such as invasion, proliferation and differentiation, using the in vitro angiogenesis model of capillary-like structure formation in three-dimensional matrices of collagen type I. Endothelial cells cultured on collagen gel with angiogenic factors (the combination of fibroblast growth factor-2 and vascular endothelial growth factor) invaded the underlying collagen matrix, and organized capillary-like cord structures in the gel. We found that endothelial cell invasion into glycated collagen gel was significantly attenuated without any effect on proteinase activity including cell-associated plasminogen activator and matrix metalloproteinase in the conditioned medium. In addition, subsequent capillary-like cord formation was also inhibited in glycated collagen gel. In contrast, endothelial cell proliferation was enhanced on glycated collagen gel with or without angiogenic factors compared with control collagen gel. These results suggest that the structural alterations of extracellular matrix proteins through the glycation-induced cross-link formation affect the interaction between endothelial cell and extracellular matrix, resulting in the impairment of an adequate neovascularization in diabetic patients. [Diabetologia (1998) 41: 491–499] [ABSTRACT FROM AUTHOR]

Imipenem-resistant clinical isolates of Pseudomonas aeruginosa were divided into two categories: (i) isolates that were moderately resistant to imipenem (MIC 6.25 mg/L) that produced trace amounts of protein D2 detected with immunoblotting using anti-protein D2 antibody, but not when stained with Coomassie blue and had inducible class 1 beta-lactamase expression; (ii) isolates that were highly resistant to several beta-lactams, including meropenem, with no protein D2 by staining or immunoblotting and had stably derepressed beta-lactamase. Laboratory strains were isolated and analyzed: (i) mutants lacking protein D2, or (ii) lacking protein D2 and producing stably derepressed beta-lactamase with carbapenem resistance similar to the clinical isolates. (iii) mutants producing undetectable beta-lactamase which were four-fold more susceptible to imipenem than the mutant producing stably derepressed beta-lactamase or the strain with inducible beta-lactamase. These data suggests that beta-lactamase and outer membrane permeability govern meropenem-resistance in P. aeruginosa. [ABSTRACT FROM AUTHOR]

Presents a letter to the editor on the sexual behaviour and high risk human papillomavirus infections in Japanese women.