Diffraction Patterns of the Millimeter Wave with a Helical Wavefront by a Triangular Aperture

In this paper, for the first time, we developed the measurement method of the topological charge (TC) in millimeter wave with helical wavefront by a triangular aperture. The millimeter wave with helical wavefront was passively generated by conversion from a Gaussian beam using a spiral mirror, which we also developed. Each diffraction pattern depended on TC, and negative TC and positive TC were symmetric pairs under reflection. These diffraction patterns were perfectly compatible with the calculation results

Platelet Serotonin (5-HT)2A Receptor Binding Sites in Affective Disorders: A Quantitative Receptor Autoradiographic Study with [ 125I ] Lysergic Acid Diethylamide

We used the quantitative receptor autoradiographic method with a radioligand of [ 125I ]lysergic acid diethylamide ([125I]LSD) to quantitate platelet serotonin (5-HT)2A receptors in affective disorders. Specific binding of [125I]LSD to human platelet pellet sections was saturable, and of high affinity and single. Both ketanserin and spiperone, 5-HT2A selective ligands, inhibited [125I]LSD binding to human platelet pellets with high potency (IC50 values of 0.15 and 0.19 nM, respectively), whereas 5-HT and paroxetine, selective 5- HT re-uptake inhibitors, inhibited binding with a very low potency. These data confirmed that binding sites of human platelet pellets specifically labelled by [125I] LSD were 5-HT2A receptors. The number of 5-HT2A receptors (Bmax of [ 125I] LSD binding) of human platelets obtained from drug-free depressed patients was significantly higher than those of healthy volunteers. There were no statistical differences in the number of 5-HT2A receptors between depressed patients with and without suicidal behaviors. The increased number in platelet 5-HT2A receptotrs may indicate a hyperfunction of the central 5-HT2A receptors. The method with human platelets pellet sections we used is simple and sensitive for investigating platelet 5-HT2A receptors, a diagnostic and therapeutic marker in depressive disorders, in the clinical research

女子スポーツ選手におけるMRI画像からみた腰椎アライメントと腰痛との関連について

Magnetic Resonance Imaging (MRI) was performed on 89 female athletes (26 handball players and 63 track and field athletes) to clarify the associations between symptoms of lumbago and lumbar alignment in MRI. The lumbar alignments are lumbosacral angle (LSA), angle of lumbar curvature (ALC), disk wedge angle (DWA) and angle of lumbosacral curvature (ALSC). The average LSA of all subjects was 140.81°±5.76 (154.82°-126.55°), ALC was 32.84°±7.84 (48.64°-13.62°), and ALSC was 46.95°±9.47 (72.34°-23.63°). The average LSA of subjects with lumbago was 140.02°±5.67, and that of subjects without lumbago 142.02°±5.76. The average ALC of subjects with lumbago was 33.00°±7.98, and that of subjects without lumbago 32.58°±7.73. There were no statistically significant correlations between lumbago and LSA or ALC. Further investigation will be required to determine whether lumbar alignment is the main cause of lumbago

Development of the calibration method for a fast steering antenna for investigating the mode conversion window used in EBW heating in the LHD plasma

In this study, we developed a calibration method for a fast steering antenna for investigating the mode conversion window used in electron Bernstein wave heating in the large helical device. The calibration was carried out in under-dense plasma against a line-of-sight with an optical thickness which varied spatially. Although multi-reflected background radiation becomes dominant in optically thin lines-of-sight, we succeeded in calibrating the fast steering antenna by including the effect of multi-reflected background radiation in the solution of the radiation transfer equation as the constant by which the temperature of the center of the plasma is multiplied. In addition, we report the initial results of experiments investigating the mode conversion window in over-dense plasma using the calibrated antenna

ゴルフスイングによると考えられた「下位頚椎・上位胸椎棘突起疲労骨折」の3例

We experienced 7 cases of Stress facture of Spinous Processes of lower Cervical Vertebra in "T" surgical hospital. One case was caused by a traffic accident, 3 were caused from work. Out of these 7 cases, 1 was caused by golf swing and 2 were caused by combination of golf swing and work. We fixed Cervical vertebra 3 month by cervical orthosis and the prognosis was favorable

Collective Thomson scattering with 77, 154, and 300 GHz sources in LHD

Collective Thomson scattering (CTS) is one of attractive diagnostics for measuring locally and directly the fuel temperature and the velocity distribution of fast ions in fusion plasmas. A mega-watt class source of millimeter or sub-millimeter waves is required to detect a weak scattered radiation superimposed on background radiation owing to electron cyclotron emissions (ECEs) from plasmas. Based on electron cyclotron resonance heating (ECRH) system with the frequencies of 77 GHz and 154 GHz in the Large Helical Device (LHD), the CTS diagnostic system has been developed to measure bulk ion temperatures from a few keV to ∼10 keV and fast ions originated from 180 keV-neutral beam injection in the LHD. The measured CTS spectra and their time evolutions are analyzed with the electrostatic scattering theory. The bulk ion temperatures obtained from CTS spectra increase with the neutral beam injections and decrease with the heating terminated. The velocity map of simulated fast ions explains that the bumps on tail of measured CTS spectra are caused by the co- and counter- fast ions. A new prescription for anisotropic velocity distribution function is proposed. As for 154 GHz bands, the CTS spectrum broadenings for D and H plasmas are distinguished reasonably at the same temperature, and its ion temperatures are comparable to those of the charge exchange recombination spectroscopy. As reactor-relevant diagnostics, a 300 GHz gyrotron and a corresponding receiver system have been implemented in LHD to access high density plasmas with low background ECEs. The recent progress for CTS diagnostics and their spectrum analysis with the probe frequencies of 77 GHz, 154 GHz, and 300 GHz in the LHD experiments is described

W-band millimeter-wave back-scattering system for high wave number turbulence measurements in LHD

A 90 GHz W-band millimeter-wave back-scattering system is designed and installed for measuring electron scale turbulence (kρs ∼ 40). Ametal lens relay antenna is used for in-vessel beam focusing, and a beam diameter of less than 40mm is achieved in the plasma core region.This antenna can be steered at an angle of 159○ ± 6○, which almost covers the plasma radius. The estimated size of the scattering volume is ∼105mm at the edge and 135mm at the core, respectively. A 60m corrugated waveguide is used to achieve a low transmission loss of ∼8 dB. A heterodyne detection system for millimeter-wave circuits with probing power modulation can distinguish the scattered signal frombackground noise

Isotope effect in transient electron thermal transport property and its impact on the electron internal transport barrier formation in LHD

In this study, we perform a comprehensive comparison of the transport hysteresis width in deuterium (D) plasmas, hydrogen (H) plasmas, and D-H mixed plasmas. The core focused modulation electron cyclotron resonance heating (MECH) is applied as the heat source perturbation, and the heat flux is evaluated using the energy conservation equation with the measured electron temperature response and the ECH deposition profile calculated by the ray-tracing scheme. Systematic density scan in plasmas with different ion mass reveals that there is no significant isotope effect in their hysteresis width. It is found that plasmas with heavier isotope mass can easily form the electron internal transport barrier. As the hysteresis width is insensitive to the isotope mass, the classical part of the diffusivity is considered to be responsible for the isotope effect in the transport barrier formation

Particle control in long-pulse discharge using divertor pumping in LHD

Density control is crucial for maintaining stable confined plasma. Divertor pumping, where neutral particles are compressed and exhausted in the divertor region, was developed for this task for the Large Helical Device. In this study, neutral particle pressure, which is related to recycling, was systematically scanned in the magnetic configuration by changing the magnetic axis position. High neutral particle pressure and compression were obtained in the divertor for a high plasma electron density and the inner magnetic axis configuration. Density control using divertor pumping with gas puffing was applied to electron cyclotron heated plasma in the inner magnetic axis configuration, which provides high neutral particle compression and exhaust in the divertor. Stable plasma density and electron temperature were maintained with divertor pumping. A heat analysis shows that divertor pumping did not affect edge electron heat conductivity, but it led to low electron heat conductivity in the core caused by electron-internal-transport-barrier-like formation