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Developments of the large negative ion source have been progressed in the high-energy, high-power, and long-pulse neutral beam injector for JT-60 Super Advanced. Countermeasures have been studied and tested for critical issues of grid heat load and voltage holding capability. As for the heat load of the acceleration grids, direct interception of D- ions was reduced by adjusting the beamlet steering. As a result, the heat load was reduced below an allowable level for long-pulse injections. As for the voltage holding capability, local electric field was mitigated by tuning gap lengths between large-area acceleration grids in the accelerator. As a result, the voltage holding capability was improved up to the rated value of 500 kV. To investigate the voltage holding capability during beam acceleration, the beam acceleration test is ongoing with new extended gap. [ABSTRACT FROM AUTHOR]

Based on previous studies on the spatial uniformity of the negative ion beam, the external magnetic filter was replaced to a novel tent-shaped magnetic filter in the JAEA 10 A negative ion source. The line-cusp field configuration on the source chamber was also changed to form a symmetric magnetic field like many of positive ion sources aiming at high proton yield. This magnetic field configuration allows fast electrons emitted from filament cathodes to rotate azimuthally inside the source chamber. The source configuration thus prevents localization of fast electrons due to their B×grad B drift in the filter field. As a result, the H- ion beam profile extracted from a wide region of 340×170 mm2 showed reduction of standard deviation from 16% in the original to 7.9% with the tent filter. The negative ion source with the tent filter satisfied the requirement of the beam uniformity for a large negative ion source in the ITER neutral beam injection. [ABSTRACT FROM AUTHOR]

In order to realize neutral beam systems in International Thermonuclear Experimental Reactor whose target is to produce a 1 MeV, 200 A/m² during 3600 s D- ion beam, the electrostatic five-stages negative ion accelerator so-called "MeV accelerator" has been developed at Japan Atomic Energy Agency. To extend pulse length, heat load of the acceleration grids was reduced by controlling the ion beam trajectory. Namely, the beam deflection due to the residual magnetic field of filter magnet was suppressed with the newly developed extractor with a 0.5 mm off-set aperture displacement. The new extractor improved the deflection angle from 6 mrad to 1 mrad, resulting in the reduction of direct interception of negative ions from 23% to 15% of the total acceleration power, respectively. As a result, the pulse length of 130 A/m², 881 keV H- ion beam has been successfully extended from a previous value of 0.4 s to 8.7 s. This is the first long pulse negative ion beam acceleration over 100 MW/m². [ABSTRACT FROM AUTHOR]

A multiaperture multigrid accelerator called “MeV accelerator” has been developed for neutral beam injection system of international thermonuclear experimental reactor. In the present work, long pulse H- ion beam acceleration was performed by the MeV accelerator equipped with new water-cooled grids. At present, the pulse length was extended to 5 s for the beams of 750 keV, 221 mA, and 10 s for the beams of 600 keV, 158 mA. Energy density, defined as products of beam energy (keV), current (mA), and pulse (s) divided by aperture area (m2), increased more than one order of magnitude higher compared with original MeV accelerator without water cooling in its grids. At higher energy and current, the grid was melted by beam deflection. Due to this grid melting, breakdowns occurred between the grids, and hence, the pulse length was limited. Beam deflection will be compensated by aperture displacement in next experiment. [ABSTRACT FROM AUTHOR]

Voltage holding capability of JT-60 negative ion source that has a large electrostatic negative ion accelerator with 45 cm×1.1 m acceleration grids was experimentally examined and improved to realize 500 keV, 22 A, and 100 s D- ion beams for JT-60 Super Advanced. The gap lengths in the acceleration stages were extended to reduce electric fields in a gap between the large grids and at the corner of the support flanges from the original 4–5 to 3–4 kV/mm. As a result, the voltage holding capability without beam acceleration has been successfully improved from 400 to 500 kV. The pulse duration to hold 500 kV reached 40 s of the power supply limitation. [ABSTRACT FROM AUTHOR]

The H- ion accelerator R&D to realize the international thermonuclear experimental reactor neutral beam is ongoing at Japan Atomic Energy Agency (JAEA). The required performance for the prototype MeV accelerator developed at JAEA is 1 MeV, 500 mA (current density of 200 A/m2) H- ion beam at the beamlet divergence angle of less than 7 mrad. Up to 2005, 836 keV, 146 A/m2 H- ion beam was successfully accelerated as the highest record of the current density at MeV class energy beams. In the present work, high current negative ion beam acceleration test was performed by increasing the beam extraction apertures from 3×3 (9 apertures) to 3×5 (15 apertures). By fixing the air leak at the source chamber due to backstream ions as well as the improvement of voltage holding capability by a new fiber reinforced plastic insulator ring, the performance of the MeV accelerator was improved. So far, H- ion beam of 320 mA was successfully accelerated up to 796 keV with the beam divergence angle of 5.5 mrad. The accelerated drain current including the electron reaches close to the power supply limit for the MeV test facility. The heat flux by the backstream ion during the above beam acceleration was estimated to be 360 W/cm2. The Cs leakage to the accelerator during the test campaign (Cs total input of 5.0 g) was 0.26 mg (7.0 μg/cm2). This is considered to be the allowable level from the viewpoint of voltage holding. [ABSTRACT FROM AUTHOR]

We have evaluated a Fermi antenna newly designed in X band for use in a multichannel reflectometer. The Fermi antenna is a tapered slot antenna provided with both a Fermi–Dirac-function-type tapered slot structure and a corrugated structure along the antenna edge in order to improve radiation patterns of the linearly tapered slot antenna. We attained a 3 dB beam width of 32° in the E plane and 37° in the H plane at 12 GHz. By optimizing the stripline dimensions according to an equivalent circuit model, a bandwidth of 8–18 GHz with a voltage standing-wave ratio less than 2 is obtained. In the mockup experiments using a rotating metal cylinder, the experimental results are in good agreement with the predicted ones. [ABSTRACT FROM AUTHOR]

A beam optics study using the ITER-relevant high intense negative ion beams, such as 1 MeV, 200 A/m 2 , has been performed experimentally and analytically using a multi-aperture and five-stage accelerator. Initially, multi-beamlets generated from this accelerator were deflected in various directions due to the magnetic field and space charge repulsion between beams and showed various divergences. These had limited the pulse length and the beam energy. Compensation methods of the beamlet deflections have worked effectively and contributed to achieving the ITER requirement, the divergence angle of <7 mrad, and the deflection angle of <1 mrad for 1 MeV beam. The beam pulse has been gradually extended from 1 to 100 s and is now going to a longer pulse based on these results. One of the remaining issues is to understand and suppress peripheral components of the beam, namely, the halo, and to reduce the local heat loads observed around the aperture edge. This halo component has been successfully distinguished from the beam core by using a newly developed beam emittance measurement system for high intense beams. By combining this measured beam emittance and the beam simulation, it was clarified for the first time that the halo components are generated in an area of 1 mm width from the aperture edge.

Long pulse negative ion beams of 500 keV and 154 A/m 2 for 118 s have been achieved for the first time, which exceeds the requirement of the JT-60SA negative ion source. In order to solve the issues of such long pulse beams, the fast cutoff system of the power supply aims to reduce the surge current and to extend the lifetime of filaments and the suppression method of excess cesium (Cs) accumulation on the plasma grid (PG) to achieve stable negative ion production. By developing the fast cutoff system using a field programmable gate array unit for the arc power supply, the cutoff time has been reduced to 1/10 that of the original system and the lifetime of the filament was extended by three times. In order to achieve stable negative ion production, incoming Cs on the PG surface has been reduced by keeping the chamber wall temperature below 40 °C. As a result, a stable beam current drift of <6% has been achieved for the 118 s duration.

The behavior of the Cesium (Cs) in Cs-seeded negative ion sources has been investigated experimentally under the beam accelerations of up to 0.5 MeV. The pulse length was extended to 100 s to catch the precise variations in the Cs D2 emission, discharge power, negative ion current, and temperatures in the ion source. The variations of the negative ions were estimated by the beam current and the heat loads in the accelerator. This experiment shows that the buildup of temperature in the chamber walls lead to the evaporation of deposited Cs to enter the plasma region and influenced H - ion production. The H - ion beams were stably sustained by reducing the temperature rise of the chamber wall below 50 °C. A stable long pulse beam could be achieved through the temperature control of the surfaces inside the source chamber walls.

Objectives: This study aimed to identify the extent of tobacco cessation training content, including the introduction of a comprehensive programme; and the presence of tobacco-related topics, including new tobacco products, school years and course of training, educators, and attitudes and policies relevant to tobacco education in pharmacy schools in Japan., Design: A cross-sectional survey., Setting: All pharmacy schools in Japan with a 6-year course of training were invited to participate., Methods: Pharmacy schools in Japan that agreed to participate in a web-based survey asking about tobacco cessation training, and attitudes and policies relevant to tobacco education., Primary and Secondary Outcome Measures: The primary outcome was the number of pharmacy schools that introduced comprehensive tobacco cessation training in their curriculum. The secondary outcome was to clarify the curriculum coverage of 9 basic knowledge and 10 tobacco cessation-specific topics, including new tobacco products., Results: Of the 75 pharmacy schools with a 6-year course in Japan, 52 (74%) responded to the survey. While 27 (52%) schools reported that comprehensive tobacco cessation training would be beneficial, only 1 school had introduced it as a one-credit elective course in the fifth year. Basic knowledge topics for tobacco cessation listed in or related to the Model Core Curriculum were covered by 44%-65% of the schools, while practical skills were covered in 10%-19% of the schools. Only seven schools (14%) introduced the topic of new tobacco products in their curriculum., Conclusions: This study revealed that comprehensive tobacco cessation training is not generally offered in pharmacy schools in Japan. The Model Core Curriculum should revise its standards to implement updated tobacco cessation training programmes to keep up with new tobacco products and to train pharmacy students on counselling users of such products., Trial Registration Number: Tokyo University of Pharmacy and Life Sciences No. 17 - 14., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

The aim of this cross-sectional study was to use standard automated perimetry to compare fixation variability among the dominant eye fixation, non-dominant eye fixation, and binocular fixation conditions. Thirty-five eyes of 35 healthy young participants underwent standard automated perimetry (Humphrey 24-2 SITA-Standard) in dominant eye fixation, non-dominant eye fixation, and binocular fixation conditions. Fixation variability during foveal threshold and visual field measurement, which was recorded using a wearable eye-tracking glass and calculated using the bivariate contour ellipse area (deg2), was compared among the three fixation conditions. Further, the association of bivariate contour ellipse area with ocular position and fusional amplitude during binocular fixation was analysed. There were no significant differences in bivariate contour ellipse area during foveal threshold measurement among the dominant eye fixation (1.75 deg2), non-dominant eye fixation (1.45 deg2), and binocular fixation (1.62 deg2) conditions. In contrast, the bivariate contour ellipse area during visual field measurement in binocular fixation (2.85 deg2) was significantly lower than the bivariate contour ellipse area in dominant eye fixation (4.62 deg2; p = 0.0227) and non-dominant eye fixation (5.24 deg2; p = 0.0006) conditions. There was no significant difference in bivariate contour ellipse area during visual field measurement between dominant eye fixation and non-dominant eye fixation conditions. There was no significant correlation between bivariate contour ellipse area and either ocular position or fusional amplitude during both foveal threshold and visual field measurements. Thus, fixation variability might be improved in binocular fixation conditions during a long-duration test, such as visual field measurement., Competing Interests: The authors have declared that no competing interests exist.

To understand the physics of the negative ion extraction/acceleration, the heat load density profile on the acceleration grid has been firstly measured in the ITER prototype accelerator where the negative ions are accelerated to 1 MeV with five acceleration stages. In order to clarify the profile, the peripheries around the apertures on the acceleration grid were separated into thermally insulated 34 blocks with thermocouples. The spatial resolution is as low as 3 mm and small enough to measure the tail of the beam profile with a beam diameter of ∼16 mm. It was found that there were two peaks of heat load density around the aperture. These two peaks were also clarified to be caused by the intercepted negative ions and secondary electrons from detailed investigation by changing the beam optics and gas density profile. This is the first experimental result, which is useful to understand the trajectories of these particles.

Objectives: To provide an occupational physician-pharmacist cooperative management for hypertension, we aimed to improve blood pressure (BP) control for workers with high-normal BP or hypertension., Method: Health checkups were performed from May 2005 to May 2008 for male professional grooms and exercise riders aged 20-69 years working at Miho Training Center, the largest racing-horse training facility in Japan. An occupational physician-pharmacist cooperative hypertension management was performed from Jan 2007 to Mar 2008, including the use of posters at the work site and letters to employers and the subjects who were diagnosed as having high-normal BP (office systolic/diastolic BPs 130-139 and/or 85-89 mmHg) or hypertension (≥ 140 and/or 90 mmHg) twice during 2005-2006 examinations. The observational study examined BP measurements before and after the hypertension management., Results: We analyzed 232 participants in the 2008 Nov examination with had high-normal BP or hypertension in both of 2005 and 2006 Nov examinations. Office systolic and diastolic BP decreased after the hypertension management by the use of educational letters and posters (-3.1 mmHg; p<0.001, -1.5 mmHg; p=0.02). The prevalence of workers with high-normal BP and hypertension also decreased after those activities (-15% and -7%; p<0.001). The subjects who started or continued the antihypertensive medication were more likely to show reductions in office BP and body mass index than those who received no treatment., Conclusions: An occupational physician-pharmacist cooperated hypertension management by the use of educational letters and posters may improve BP control for subjects with high-normal BP or hypertension.

Background: The aim of the trial was to evaluate the effectiveness of a program of cooperation between physician and pharmacist to reduce cardiovascular risk factors in patients with mild to moderate hypertension by promoting better blood pressure (BP) control, appropriate changes in antihypertensive medications, and beneficial changes in lifestyle., Methods: The 132 subjects in this randomized, controlled trial were in the age range of 40-79 years. The inclusion criteria were: systolic BP (SBP) ranging from 140-179 mm Hg and/or diastolic BP (DBP) ranging from 90-99 mm Hg and treatment-naive (untreated for hypertension); or on a regimen of medication for hypertension. Of these 132 subjects, 124 (94%) were already receiving treatment with antihypertensive medications. Equal numbers of subjects were randomly assigned to one of two groups: a physician-pharmacist intervention group (n = 66) and a control group (n = 66)., Results: The 6-month follow-up rate was 97% in both groups. At 6 months, the mean decrease in SBP/DBP, as measured at home in the morning, was 2.9/3.3 mm Hg in the intervention group relative to baseline (P = 0.02 and P < 0.0001 for SBP and DBP, respectively). The mean decrease in home morning SBP in the intervention group was not significantly greater than in the control group. However, the DBP decline was significantly greater in the intervention than control groups, which showed a mean decrease of 2.8 mm Hg (confidence interval: -5.5 to -0.1; P = 0.04). The percentage of patients in whom control of home morning BP was achieved was 53% in the intervention group and 47% in the control group (P = 0.40). A higher percentage of patients in the intervention group, relative to the control group, were able to reduce the use of antihypertensive medications (31 vs. 8%, P < 0.0001), and fewer patients in this group required additional medications or increases in dosage relative to the controls (11 vs. 28%, P = 0.03). Patients of the intervention group were more likely to show reduction in body mass index and sodium intake and to stop smoking, as compared with the control group., Conclusions: A program of cooperation between physician and pharmacist was successful in reducing cardiovascular risk factors in patients with mild to moderate hypertension by promoting better blood pressure (BP) control, appropriate changes in antihypertensive medications, and beneficial changes in lifestyle.

Objectives: Prevention of horse-related injuries is considered difficult because horse behavior is unpredictable. Therefore, risk factors for injuries related to professional horse racing need to be investigated. We conducted a study to determine whether body mass index (BMI) and gamma-glutamyltransferase (GGT) levels are associated with professional horse racing-related injuries., Methods: A baseline healthy survey of 546 male grooms and exercise riders aged 40-70 yr working at Miho Training Center, the largest racing-horse training facility in Japan, was performed in May 2003. A total of 93 occupational injuries occurred from June 1, 2003 to December 31, 2005. The Cox proportional hazards model was used to examine associations between the risk of injury and BMI and GGT., Results: Grooms and exercise riders with BMI <20 kg/m2 or with BMI > or =25 kg/m2 compared to BMI=20.0-22.9 kg/m(2) had 2.5 to 3.5-fold higher age-adjusted risks of injuries. The multivariate hazard ratios (95% confidence interval) after adjustment for age, GGT, smoking habit, and history of injuries were 3.5 (1.5 to 8.4) and 2.4 (1.2 to 4.8) for grooms, 3.1 (1.2 to 8.2) and 1.9 (0.4 to 10.1) for exercise riders, respectively. The age-adjusted hazard ratio of injuries for persons with GGT > or =100 IU/l was 2.0 to 2.5-fold higher than for those with GGT <60 IU/l. The multivariate hazard ratios were 1.9 (1.0 to 3.6) for grooms and 2.5 (1.0 to 6.2) for exercise riders., Conclusions: Low and high BMI and high GGT were associated with professional horse racing-related injuries.

Production and transport processes of the H(0) atoms are numerically simulated using a three-dimensional Monte Carlo transport code. The code is applied to the large JAEA 10 ampere negative ion source under a Cs-seeded condition to obtain a spatial distribution of surface-produced H(-) ions. In this analysis, we focus on the effect of the energy relaxation of the H(0) atoms at the wall on the H(-) ion production from the H(0) atoms. The result indicates that, by considering the energy relaxation of the H(0) atoms at the wall, the production profile of the surface-produced H(-) ion is well reflected in the production profile of the H(0) atom production.

Generation of oxygen-derived free radicals (oxy-radicals) in the stored rat heart was measured by chemiluminescence. Hearts subjected (ischemia) or not subjected (non-ischemia) to a 4-min regional ischemia were frozen in liquid nitrogen and stored until assayed. The frozen myocardium was ground and oxygenated by mixing it with phosphate-buffered saline (Po2: 194 mmHg) containing lucigenin. The chemiluminescence intensity of ischemic myocardium was larger than that of non-ischemic myocardium. Recombinant human superoxide dismutase significantly decreased these intensities. These results indicate that O2- is one of the major oxy-radical species in the rat heart and that the generation of oxyradicals is enhanced by regional ischemia for 4 min.

We have developed a simple and reproducible method employing chemiluminescence to measure oxygen-derived free radicals generated in oxygenated myocardium. Isolated perfused rat hearts were frozen in liquid nitrogen during the control perfusion (non-ischemia), after 30 min of global ischemia (ischemia), or after 20 min of reperfusion following 30-min global ischemia (reperfusion). The frozen hearts were ground to a fine powder and then oxygenated by mixing with phosphate-buffered saline (PBS) (pH 7.4 and PO2 183-194 mmHg) containing lucigenin. The mixed solution was injected into a chemiluminescence detection flow cell. The chemiluminescence intensity increased in relation to the lucigenin and myocardium contents of the test solution. However, it was not affected by the temperature of PBS in the range of 25 degrees C to 50 degrees C. The chemiluminescence intensity of ischemic myocardium was 2.5 times larger than that of non-ischemic or reperfused myocardium (P < 0.01). Recombinant human superoxide dismutase (r-h-SOD) reduced dose-dependently the chemiluminescence intensity induced by oxygenation of ischemic myocardium, while chemically inactivated r-h-SOD did not.

The following results have been obtained in consequence of patho-morphological examination regarding the supplemental groove. 1. Light microscopic observation of cross-sectioned supplemental grooves revealed that most of them were shallow in the form of plate or bowl. Some of the supplemental grooves had contents not described in the past and the structure of the contents was not clear under a light microscope. The contents were found in 22% of the supplemental grooves examined. 2. The contents in supplemental grooves which were confirmed under a light microscope were found to consist of enamel itself when examined by means of an electron microscope. Microhardness measurements of this enamel showed less than one third the values of normal enamel. By means of microradiography, it was established that radiolucency of this enamel was, for the most part, much higher than normal enamel. 3. It was ascertained that enamel with low hardness and high radiolucency constitutes the contents of supplemental grooves. Judging from its tissue properties, the contents were believed to be susceptible to attack by caries. This view was supported by the results of an investigation of caries sites in supplemental grooves.