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The use of a cusp magnetic field is studied to improve the thrust performance of small electrodeless radio frequency (RF) plasma thrusters based on a theoretical analysis of a magnetized inductively coupled plasma. In this type of thruster, electrons play a critical role in determining the thrust performance. The electron energy probability function (EEPF) and two-dimensional profiles of the plasma parameters in the cusp-type magnetic field RF thruster are investigated to characterize the plasma flow. Non-Maxwellian EEPFs were obtained, which correspond to the pressure and plasma potential profiles in the plasma plume. In addition, the axial ion velocity was measured, and the presence of ion flux in the downstream direction is revealed, indicating ideal ion acceleration. [ABSTRACT FROM AUTHOR]

The use of a cusp magnetic field is studied to improve the thrust performance of small electrodeless radio frequency (RF) plasma thrusters based on a theoretical analysis of a magnetized inductively coupled plasma. In this type of thruster, electrons play a critical role in determining the thrust performance. The electron energy probability function (EEPF) and two-dimensional profiles of the plasma parameters in the cusp-type magnetic field RF thruster are investigated to characterize the plasma flow. Non-Maxwellian EEPFs were obtained, which correspond to the pressure and plasma potential profiles in the plasma plume. In addition, the axial ion velocity was measured, and the presence of ion flux in the downstream direction is revealed, indicating ideal ion acceleration. [ABSTRACT FROM AUTHOR]

In typical electrodeless radio frequency plasma thrusters, application of a rotating magnetic field (RMF) is expected to drive an azimuthal electron current via the non-linear Hall-term effect, resulting in an additional electromagnetic acceleration effect in the presence of a diverging magnetic field. Large increases in ion Mach number and electron density were found, comparing cases with and without the RMF, under a partial RMF penetration into a plasma. Spatial characteristics of the RMF acceleration were investigated to clarify the causes of these increments: 2D profiles of plasma parameters and time-varying RMF components were measured. Partial penetration of the RMF into plasma with a phase retardation was found, but the RMF azimuthal current was driven. Large diamagnetic current derived from the large density gradient also increased by the RMF application. Synergistic acceleration effect derived from the driven RMF current and the density gradient results in the plasma acceleration effect even under the partial penetration. [ABSTRACT FROM AUTHOR]

Background: In fixed‐dose antidepressant trials, the lower range of the licensed dose achieves the optimal balance between efficacy and tolerability. Whether flexible upward titration while side‐effects permit provides additional benefits is unknown. Methods: We did a systematic review of placebo‐controlled randomized trials that examined selective serotonin reuptake inhibitors (SSRIs), venlafaxine or mirtazapine in the acute treatment of major depression. Our primary outcome was response, defined as 50% or greater reduction in depression severity. Secondary outcomes included drop‐outs due to adverse effects and drop‐outs for any reason. We conducted random‐effects meta‐analyses to calculate the ratios of odds ratios (RORs) between trials comparing the flexible dose titrating above the minimum licensed dose against placebo and those comparing the fixed minimum licensed dose against placebo. Results: We included 123 published and unpublished randomized controlled trials (29 420 participants). There was no evidence supporting efficacy of the flexible dosing over the fixed low dose of SSRIs (ROR 0.96, 95% CI: 0.73 to 1.25), venlafaxine (1.24, 0.96 to 1.60) or mirtazapine (0.77, 0.33 to 1.78). No important differences were noted for tolerability or for any subgroup analyses except the superior efficacy of venlafaxine flexible dosing between 75 and 150 mg over the fixed 75 mg (1.30, 1.02 to 1.65). Conclusion: There was no evidence to support added value in terms of efficacy, tolerability or acceptability of flexibly titrating up the dosage over the minimum licensed dose of SSRIs or mirtazapine. For venlafaxine, increased efficacy can be expected by flexibly titrating up to 150 mg. [ABSTRACT FROM AUTHOR]

Objective: In modern psychiatry, depression is diagnosed with the diagnostic criteria; however, the trajectory of each of the criterion symptoms is unknown. This study aims to examine this. Methods: We made repeated assessments of the nine diagnostic criterion symptoms with the Patient Health Questionnaire‐9 (PHQ‐9) among 2011 participants of a 25‐week pragmatic randomised controlled trial of sertraline and/or mirtazapine for hitherto untreated major depressive episodes. The changes from baseline were estimated with the mixed‐effects model with repeated measures. The time to disappearance of each symptom was modeled using the Kaplan–Meier survival analysis. Results: The total score on PHQ‐9 was 18.5 (SD = 3.9, n = 2011) at baseline, which decreased to 15.3 (5.2, n = 2011) at week 1, to 11.5 (5.9, n = 1953) at week 3, to 7.8 (6.0, n = 1927) at week 9, and to 6.0 (5.9, n = 1910) at week 25. Suicidal ideas, psychomotor symptoms decreased rapidly, while anergia and sleep disturbance also decreased but only slowly. The survival analyses confirmed the primary analyses. Conclusions: Upon initiation of antidepressant treatment, patients with newly treated major depressive episodes can expect their suicidal ideas and psychomotor symptoms to disappear first but sleep disturbances and anergia to linger on. [ABSTRACT FROM AUTHOR]

A study of multiple-ion therapy with charged heavy-ion beams was performed to improve outcomes of refractory cancer treatments. We proposed the accelerator operation method for applying the multiple-ion therapy, to quickly switch the ion species and energies of the output beams. In this method, the irradiation ion species can be changed only by switching the selected ion source and the injector parameters, and the output beam energies can be varied without changing the magnetic operation patterns of the synchrotron. We verified the effectiveness of our approach by conducting experiments at the Heavy Ion Medical Accelerator in Chiba (HIMAC) and confirmed that the approach can provide the fast switching of both the ion species and the beam energies. The experimental results also demonstrated that our approach will greatly reduce the commissioning time and the routine adjustments for multiple-ion beams. [ABSTRACT FROM AUTHOR]

Simultaneous measurements of the charge Q and the capacitance C were performed for an MFS capacitor with Au-(vinylidene fluoride-trifluoroethylene copolymer)-(n-Si) structure using a double-frequency voltage consisting of a low-frequency high voltage and a high-frequency sinusoidal low voltage. The use of a triangular high voltage yields asymmetrical Q-V and C-V hysteresis loops that support the full ferroelectric polarization reversal occurring in close relation to charge compensation in the n-Si layer. The use of a rectangular high voltage reveals the details of asymmetric switching dynamics. Polarization switching toward the positive side starts with the loss of the depletion layer and progresses rapidly owing to the accumulation of majority carriers to be completed at a time analogous to that for the case of a metal-ferroelectric-metal capacitor. On the other hand, that toward the negative side is markedly impeded by depletion layer formation but is eventually completed via a constant-current process at a time given by the ratio of switched polarization and constant current. On the basis of a linear relationship between the constant current and the depletion layer width, we conclude that the switching dynamics under a negative voltage is controlled by the rate of minority carrier generation in the depletion layer. [ABSTRACT FROM AUTHOR]

Piezoelectric resonance spectroscopy was employed to elucidate the microscopic mechanisms of piezoelectricity and its relaxation for the uniaxially-drawn and poled films of polyvinylidene fluoride and the vinylidene fluoride/trifluoroethylene copolymer with a composition of 75/25 mol. The former was semicrystalline whereas the latter consisted of extended-chain crystals. Accurate measurements of dielectric frequency spectra in the mHz-to-GHz range revealed piezoelectric resonance superimposed on broad dielectric relaxation. Analyses of the resonance spectra of the length, width and thickness vibrations allowed for evaluation of all elastic and piezoelectric tensor components. The single-crystalline copolymer substantiated the crystalline relaxation associated with intramolecular rotational fluctuations of trans segments and longitudinal chain softening. The most informative were the piezoelectric e 31 , e 32 , and e 33 constants expressing the charge responses induced by chain elongation, interchain separations parallel and perpendicular to thickness, respectively. It was found that e 31 showed relaxation from small negative to large positive, and e 33 was much larger than e 32 both being negative and non-relaxational. These results were discussed in reference to those of Form I crystals whose polar axis was π/6 tilted due to (110) twin. We identified three microscopic mechanisms (i) elongation of relaxing chain reduces the effective monomer dipole moment μ due to reduction of rotational fluctuations, (e 31 > 0), (ii) the increase in interchain distance reduces μ due to decrease in positive local field, (e 32 , e 33 < 0), (iii) the strain-induced reduction of dipole density (dimensional effect) is effective in experimental e 33 but is absent in e 32 and e 31. The piezoelectric tensor components determined in this study were consistent with the electrostrictive coupling measured from the strain-induced change in dielectric permittivity and the strain proportional to the square of polarization. [Display omitted] [ABSTRACT FROM AUTHOR]

We have calculated the dc Josephson current through double barrier superconducting junctions. Using a formula derived by Furusaki and Tsukada [Solid State Commun. 78, 299 (1991)], we have numerically estimated the current-phase relationship from the probability amplitude of the Andreev reflections in the junctions, and also discussed the resonant phenomena of quasiparticles. Moreover, using the obtained current-phase relationship, we have analyzed the characteristics of superconducting quantum interference devices containing double barrier superconducting junctions. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Time-varying, azimuthal electron current is obtained from measured two-dimensional profiles of excited magnetic fields, using the Rotating Magnetic Field (RMF) plasma acceleration method in an open magnetic field configuration. The RMF is applied orthogonally to cylindrical plasma, leading to the azimuthal current drive via the Hall effect. Here, dc azimuthal current, whose magnitude is equivalent to that of ac azimuthal current with twice the RMF frequency, is verified for the first time. In addition, an expected current reversal is found, with the RMF rotation direction changing by 180°. [ABSTRACT FROM AUTHOR]

A two-dimensional scanning probe instrument has been developed to survey spatial plasma characteristics in our electrodeless plasma acceleration schemes. In particular, diagnostics of plasma parameters, e.g., plasma density, temperature, velocity, and excited magnetic field, are essential for elucidating physical phenomena since we have been concentrating on next generation plasma propulsion methods, e.g., Rotating Magnetic Field plasma acceleration method, by characterizing the plasma performance. Moreover, in order to estimate the thrust performance in our experimental scheme, we have also mounted a thrust stand, which has a target type, on this movable instrument, and scanned the axial profile of the thrust performance in the presence of the external magnetic field generated by using permanent magnets, so as to investigate the plasma captured in a stand area, considering the divergent field lines in the downstream region of a generation antenna. In this paper, we will introduce the novel measurement instrument and describe how to measure these parameters. [ABSTRACT FROM AUTHOR]

Objective : The role of baseline severity as effect modifier in various psychiatric disorders is a topic of controversy and of clinical import. This study aims to examine whether baseline severity modifies the efficacy of various antidepressants for major depression through individual participant data (IPD) meta‐analysis. Method: We identified all placebo‐controlled, double‐blind randomised trials of new generation antidepressants in the acute phase treatment of major depression conducted in Japan and requested their IPD through the public–private partnerships (PPPs) between the relevant academic societies and the pharmaceutical companies. The effect modification by baseline depression severity was examined through six increasingly complex competing mixed‐effects models for repeated measures. Results: We identified eleven eligible trials and obtained IPD from six, which compared duloxetine, escitalopram, mirtazapine, paroxetine or bupropion against placebo (total n = 2464). The best‐fitting model revealed that the interaction between baseline severity and treatment was not statistically significant (coefficient = −0.04, 95% confidence interval: −0.16 to 0.08, P = 0.49). Several sensitivity analyses confirmed the robustness of the findings. Conclusion: We may expect as much benefit from antidepressant treatments for mild, moderate or severe major depression. Clinical practice guidelines will need to take these findings into consideration. [ABSTRACT FROM AUTHOR]

Objective: Our analysis aimed at comparing the placebo effect sizes from randomized controlled trials (RCTs) of two widely prescribed antidepressants, namely duloxetine and venlafaxine, and at analysing a potential influence of the investigated drugs on the placebo response. Method: We conducted a comprehensive systematic review and meta‐analysis of placebo‐controlled, double‐blind RCTs, which examined the efficacy of duloxetine and venlafaxine in the acute treatment of major depressive disorder. Results: We included 71 studies (29 duloxetine trials and 43 venlafaxine trials; one study provided data for the duloxetine and the venlafaxine data set). The placebo effect sizes, defined as pre‐postscore change divided by baseline standard deviation, differed significantly between venlafaxine and duloxetine studies (−2.51 vs. −2.09; test for subgroup differences P = 0.028; high heterogeneity). The analysis of effect modifiers and the metaregression analyses confirmed the drug, next to baseline depression severity and publication status, as the most influential independent predictor. Conclusion: Our analyses show a significant difference in the placebo response between venlafaxine and duloxetine trials and suggest that the investigated drug has an influence on the placebo response that is not related to baseline severity, changes over the years or other variables we included. [ABSTRACT FROM AUTHOR]

A two-dimensional scanning probe instrument has been developed to survey spatial plasma characteristics in our electrodeless plasma acceleration schemes. In particular, diagnostics of plasma parameters, e.g., plasma density, temperature, velocity, and excited magnetic field, are essential for elucidating physical phenomena since we have been concentrating on next generation plasma propulsion methods, e.g., Rotating Magnetic Field plasma acceleration method, by characterizing the plasma performance. Moreover, in order to estimate the thrust performance in our experimental scheme, we have also mounted a thrust stand, which has a target type, on this movable instrument, and scanned the axial profile of the thrust performance in the presence of the external magnetic field generated by using permanent magnets, so as to investigate the plasma captured in a stand area, considering the divergent field lines in the downstream region of a generation antenna. In this paper, we will introduce the novel measurement instrument and describe how to measure these parameters. [ABSTRACT FROM AUTHOR]

We have proposed Rotating Magnetic Field (RMF) acceleration method as one of electrodeless plasma accelerations. In our experimental scheme, plasma generated by an rf (radio frequency) antenna, is accelerated by RMF antennas, which consist of two-pair, opposed, facing coils, and these antennas are outside of a discharge tube. Therefore, there is no wear of electrodes, degrading the propulsion performance. Here, we will introduce our RMF acceleration system developed, including the experimental device, e.g., external antennas, a tapered quartz tube, a vacuum chamber, external magnets, and a pumping system. In addition, we can change RMF operation parameters (RMF applied current IRMF and RMF current phase difference ϕ, focusing on RMF current frequency fRMF) by adjusting matching conditions of RMF, and investigate the dependencies on plasma parameters (electron density ne and ion velocity vi); e.g., higher increases of ne and vi (~360 % and 55 %, respectively) than previous experimental results were obtained by decreasing fRMF from 5 MHz to 0.7 MHz, whose RMF penetration condition was better according to Milroy's expression. Moreover, time-varying component of RMF has been measured directly to survey the penetration condition experimentally. [ABSTRACT FROM AUTHOR]

Since 2011, a three-dimensional (3D) scanning irradiation system has been utilized for treatments at the National Institute of Radiological Sciences-Heavy Ion Medical Accelerator in Chiba (NIRS-HIMAC). In 2012, a hybrid depth scanning method was introduced for the depth direction, in which 11 discrete beam energies are used in conjunction with the range shifter. To suppress beam spread due to multiple scattering and nuclear reactions, we then developed a full energy scanning method. Accelerator tuning and beam commissioning tests prior to a treatment with this method are time-consuming, however. We therefore devised a new approach to obtain the pencil beam dataset, including consideration of the contribution of large-angle scattered (LAS) particles, which reduces the time spent on beam data preparation. The accuracy of 3D dose delivery using this new approach was verified by measuring the dose distributions for different target volumes. Results confirmed that the measured dose distributions agreed well with calculated doses. Following this evaluation, treatments using the full energy scanning method were commenced in September 2015. [ABSTRACT FROM AUTHOR]

The HIMAC clinical study has been conducted with a carbon-ion beam since June 1994. Since 2006, as a new treatment research project, NIRS has developed both the accelerator and beam-delivery technologies for the sophisticated heavy-ion radiotherapy, which brings a pencil-beam 3D rescanning technology for both the static and moving-tumor treatments. In this technology, the depth-scanning technique was improved to the full-energy depth scanning by realizing a variable-energy operation of the HIMAC synchrotron itself. At present, a heavy-ion rotating gantry has been developed with the superconducting technology and is in a beam-commissioning stage. As a future plan, we just start a study of a multi-ions irradiation for more sophisticated LET-painting and a design study of a superconducting synchrotron for more compact heavy-ion radiotherapy facility. [ABSTRACT FROM AUTHOR]

A ridge filter (RGF), a beam energy modulation device, is usually used for particle radiotherapy with a pencil beam scanning system. The conventional RGF has a one-dimensional (1D) periodic laterally stepped structure in orthogonal plane with a central beam direction. The energy of a beam passing through the different thicknesses of the stepped RGF is modulated. Although the lateral pencil beam size is required to cover the several stepped RGF units to modulate its energy as designed, the current trend is to decrease lateral beam size to improve the scanning system. As a result, the beam size becomes smaller than the size of the individual RGF unit. The aim of this study was to develop a new RGF with two-dimensional (2D) honeycomb geometry to simultaneously achieve both a decrease in lateral beam size and the desired energy modulation. The conventional 1D-RGF and the 2D-RGF with honeycomb geometry were both designed so that the Bragg peak size of a 79 MeV/u carbon ion pencil beam in water was 1 mm RMS in the beam direction. To validate the design of the 2D-RGF, we calculated depth dose distributions in water using a simplified Monte Carlo method. In the calculations, we decreased the lateral pencil beam size at the entrance of the RGF and investigated the threshold of lateral beam size with which the pencil beam can reproduce the desired Bragg peak size for each type of RGF. In addition, we calculated lateral dose distributions in air downstream from the RGF and evaluated the inhomogeneity of the lateral dose distributions. Using the 2D-RGF, the threshold of lateral beam size with which the pencil beam can reproduce the desired Bragg peak size was smaller than that using the 1D-RGF. Moreover, the distance from the RGF at which the lateral dose distribution becomes uniform was shorter using the 2D-RGF than that using the 1D-RGF. These results indicate that when the periodic length of both RGFs is the same, the 2D-RGF allows use of a pencil beam with smaller lateral beam size and a shorter distance from the RGF to the target, resulting in improvement in the conformity of dose distribution in a tumor. [ABSTRACT FROM AUTHOR]

At National Institute of Radiological Sciences (NIRS), we have been commissioning a rotating-gantry system for carbon-ion radiotherapy. This rotating gantry can transport heavy ions at 430 MeV/u to an isocenter with irradiation angles of ±180° that can rotate around the patient so that the tumor can be irradiated from any direction. A three-dimensional pencil-beam scanning irradiation system equipped with the rotating gantry enables the optimal use of physical characteristics of carbon ions to provide accurate treatment. To ensure the treatment quality using such a complex system, the calibration of the primary dose monitor, output check, range check, dose rate check, machine safety check, and some mechanical tests should be performed efficiently. For this purpose, we have developed a measurement system dedicated for quality assurance (QA) of this gantry system: the Daily QA system. The system consists of an ionization chamber system and a scintillator system. The ionization chamber system is used for the calibration of the primary dose monitor, output check, and dose rate check, and the scintillator system is used for the range check, isocenter, and gantry angle. The performance of the Daily QA system was verified by a beam test. The stability of the output was within 0.5%, and the range was within 0.5 mm. The coincidence of the coordinates between the patient-positioning system and the irradiation system was verified using the Daily QA system. Our present findings verified that the new Daily QA system for a rotating gantry is capable of verifying the irradiation system with sufficient accuracy. [ABSTRACT FROM AUTHOR]

At Heavy Ion Medical Accelerator in Chiba (HIMAC) in National Institute of Radiological Sciences (NIRS), more than 9000 patients have been successfully treated by carbon ion beams since 1994. The successful results of treatments have led us to construct a new treatment facility equipped with a three-dimensional pencil beam scanning irradiation system, which is one of sophisticated techniques for cancer therapy with high energetic ion beam. This new facility comprises two treatment rooms having fixed beam lines and one treatment room having rotating gantry line. The challenge of this project is to realize treatment of a moving target by scanning irradiation. Thus, to realize this, the development of the fast scanning system is one of the most important issues in this project. After intense commissioning and quality assurance tests, the treatment with scanned ion beam was started in May 2011. After treatment of static target starts, we have developed related technologies. As a result, we can start treatment of moving target and treatment without range shifter plates since 2015. In this paper, the developments of the scanning irradiation system are described. [ABSTRACT FROM AUTHOR]

Multiple-energy synchrotron operation was developed to realize fast 3D scanning irradiation for carbon-ion radiotherapy. This type of operation can output various carbon-ion beams with different energies in a single synchrotron cycle. The beam control system used in this kind of operation was developed to quickly provide the beam energy and intensity required from the irradiation control system. The performance of the system was verified by experimental tests. The system could output beams of 197 different energies in 63 s. The beam intensity could be controlled for all the output beams without large ripples or overshooting. The experimental test of irradiation for prostate cancer treatment was also successfully performed, and the test results proved that our system can greatly reduce the irradiation time. [ABSTRACT FROM AUTHOR]

As one of the electromagnetic plasma acceleration systems, we have proposed a rotating magnetic field (RMF) acceleration scheme to overcome the present problem of direct plasma-electrode interactions, leading to a short lifetime with a poor plasma performance due to contamination. In this scheme, we generate a plasma by a helicon wave excited by a radio frequency (rf) antenna which has no direct-contact with a plasma. Then, the produced plasma is accelerated by the axial Lorentz force fz=jϑ x Br (jϑ is an azimuthal current induced by RMF, and Br is an external radial magnetic field). Erosion of electrodes and contamination are not expected in this total system since RMF coils and an rf antenna do not have contact with the plasma directly. Here, we have measured the plasma parameters (electron density ne and axial ion velocity vi) to demonstrate this RMF acceleration scheme by the use of AC currents in two sets of opposing coils to generate a RMF. The maximum increasing rate Δvi/vi was 28% (maximum vi of 3 km/s), while the density increasing rate of Δne/ne is 70% in the case of a RMF current frequency fRMF of 3 MHz, which showed a better plasma performance than that with fRMF=5MHz. Moreover, thrust characteristics such as a specific impulse and a thrust efficiency were discussed, although a target plasma was not optimized. [ABSTRACT FROM AUTHOR]

Provides information on the magnetic properties and microstructure of iron-chromium-cobalt (Fe-Cr-Co)-base cold-rolled magnets. Formation of sheet magnets of Fe-Cr-Co-base alloys; Effects of silicon, titanium and copper additions on magnetic properties and microstructures; Chemical compositions of typical alloys.

The high temperature corrosion behavior of two 9Cr and 12Cr ferritic–martensitic steel grades was studied under CO 2 pressures varying from 1 to 250 bar for exposure times up to 8000 h. No “breakaway” oxidation was observed. 9Cr steel grades suffered from fast parabolic uniform oxidation and fast carburisation. Increasing CO 2 pressure had very little effect on the oxidation rate but increased the carburisation rate. The corrosion behavior of both 12Cr steel grades differed and might be influenced by gas composition, minor elements or surface finish. A corrosion mechanism coupling oxidation and carburisation is proposed. [ABSTRACT FROM AUTHOR]

Background: Cognitive behavioral therapy (CBT) usually involves homework, the completion of which is a known predictor of a positive outcome. The aim of the present study was to examine the session-by-session relationships between enthusiasm to complete the homework and the improvement of psychological distress in depressed people through the course of therapy. Methods: Working people with subthreshold depression were recruited to participate in the telephone CBT (tCBT) program with demonstrated effectiveness. Their enthusiasm for homework was enhanced with motivational interviewing techniques and was measured by asking two questions: "How strongly do you feel you want to do this homework?" and "How confident do you feel you can actually accomplish this homework?" at the end of each session. The outcome was the K6 score, which was administered at the start of each session. The K6 is an index of psychological distress including depression and anxiety. We used structural equation modeling (SEM) to elucidate the relationships between enthusiasm and the K6 scores from session to session. Results: The best fitting model suggested that, throughout the course of behavior therapy (BT), enthusiasm to complete the homework was negatively correlated with the K6 scores for the subsequent session, while the K6 score measured at the beginning of the session did not influence the enthusiasm to complete the homeworks assigned for that session. Conclusions: Empirical data now support the practitioners of BT when they try to enhance their patient's enthusiasm for homework regardless of the participant's distress, which then would lead to a reduction in distress in the subsequent week. [ABSTRACT FROM AUTHOR]

A new laser spectroscopic method named 'OROCHI (Optical RI-atom Observation in Condensed Helium as Ion catcher)' has been developed for deriving the nuclear spins and electromagnetic moments of low-yield exotic nuclei. In this method, we observe atomic Zeeman and hyperfine structures using laser-radio-frequency/microwave double-resonance spectroscopy. In our previous works, double-resonance spectroscopy was performed successfully with laser-sputtered stable atoms including non-alkali Au atoms as well as alkali Rb and Cs atoms. Following these works, measurements with Rb energetic ion beams were carried out in the RIKEN projectile fragment separator (RIPS). In this paper, we report the present status of OROCHI and discuss its feasibility, especially for low-yield nuclei such as unstable Au isotopes. [ABSTRACT FROM AUTHOR]

We demonstrate spin-exchange optical pumping of Xe atoms with our newly made laser system. The new laser system was prepared to provide higher laser power required for the stable operation of spin maser oscillations in the Xe EDM experiment. We studied the optimum cell temperature and pumping laser power to improve the degree of Xe spin polarization. The best performance was achieved at the cell temperature of 100 C with the presently available laser power of 1 W. The results show that a more intense laser is required for further improvement of the spin polarization at higher cell temperatures in our experiment. [ABSTRACT FROM AUTHOR]

Quantum spin liquids, which are spin versions of quantum matter, have been sought after in systems with geometrical frustration. We show that disorder drives a classical magnet into a quantum spin liquid through conducting NMR experiments on an organic Mott insulator,κ -(ET)2Cu[N(CN)2]Cl. Antiferromagnetic ordering in the pristine crystal, when irradiated by x rays, disappears. Spin freezing, spin gap, and critical slowing down are not observed, but gapless spin excitations emerge, suggesting a novel role of disorder that brings forth a quantum spin liquid from a classical ordered state. [ABSTRACT FROM AUTHOR]

A newly found fast radiative cooling process of C 6 - is studied by simulation based on statistical sharing of the internal energy by the vibrational modes both in the electronic ground and excited states. For comparison, a contrasting slow cooling of C 6 H − is simulated by the same procedure. The simulation demonstrates a distinct difference in the time evolution of energy distributions between C 6 - and C 6 H − , and well reproduces the observed fast cooling of C 6 - by recurrent electronic transitions and the slow cooling of C 6 H − by vibrational de-excitation. [ABSTRACT FROM AUTHOR]

We have been developing a new nuclear laser spectroscopy method named 'OROCHI' (Optical RI-atom Observation in Condensed Helium as Ion-catcher). OROCHI utilizes superfluid helium (He II) not only as an efficient stopping medium of highly energetic ions but also as a host matrix of in-situ atomic laser spectroscopy. Using these characteristic of He II, we produce atomic spin polarization and measure Zeeman and hyperfine structure (HFS) splitting using laser-RF (radio frequency) / MW (microwave) double resonance method. From the measured energy splittings, we can deduce nuclear spins and moments. So far, we have conducted a series of experiments using both stable (Rb, Cs, Au, Ag) and unstable isotopes (Rb) to confirm the feasibility of OROCHI method, especially observing Zeeman resonance and determining nuclear spins. The measurement of HFS splitting of atoms introduced into He II is indispensable to clarify the nuclear properties by deducing nuclear moments as well as the study of nuclear spins. For this purpose, we perform a precision measurement of HFS of Cs atoms immersed in He II using laser ablation technique. In this paper, we describe the result of the experiment. [ABSTRACT FROM AUTHOR]

Objective Various control conditions have been employed in psychotherapy trials, but there is growing suspicion that they may lead to different effect size estimates. The present study aims to examine the differences among control conditions including waiting list ( WL), no treatment ( NT) and psychological placebo ( PP). Method We comprehensively searched for all randomized controlled trials ( RCTs) comparing cognitive-behaviour therapies ( CBT) against various control conditions in the acute phase treatment of depression, and applied network meta-analysis (NMA) to combine all direct and indirect comparisons among the treatment and control arms. Results We identified 49 RCTs (2730 participants) comparing WL, NT, PP and CBT. This network of evidence was consistent, and the effect size estimates for CBT were substantively different depending on the control condition. The odds ratio of response for NT over WL was statistically significant at 2.9 (95% CI: 1.3-5.7). However, the quality of evidence, including publication bias, was less than ideal and none of the preplanned sensitivity analyses limiting to high-quality studies could be conducted, while findings of significant differences did not persist in post hoc sensitivity analyses trying to adjust for publication bias. Conclusion There may be important differences in control conditions currently used in psychotherapy trials. [ABSTRACT FROM AUTHOR]

Abstract: For the quality assurance (QA) of therapeutic scanned carbon-ion beams, QA tool having high spatial resolution is required. The radiochromic film (such as Gafchromic EBT2 film model) is a very useful tool because of its high spatial resolution, self-development, and near tissue equivalence. However, for a complex field in carbon-ion therapy, it is difficult to unambiguously determine the dose from the measured net optical density (OD). As a first approach, we investigated the response of EBT2 to carbon-ion beam at the Heavy Ion Medical Accelerator in Chiba (HIMAC) in Japan. Based on the measured results, we performed QA measurements independently of dose. We verified the QA measurements by EBT2 by comparing the ionization chamber and the fluorescent screen. The results obtained with EBT2 were in good agreement with those obtained with the other detector. In addition, to test the use in a complex field, we verified the OD distributions for moving and static target by means of a gamma index analysis. As a result, we confirmed that EBT2 could be used as a part of QA procedures for therapeutic scanned carbon-ion beams. [Copyright &y& Elsevier]

Abstract: The NIRS has carried out carbon-ion radiotherapy (RT) with HIMAC since 1994. On the basis of their ten-year HIMAC experience, NIRS has developed a standard-type CIRT facility in order to boost availability of carbon-ion RT in Japan. Work has been carried out at its pilot facility at Gunma University since 2010. The current projects of the pilot facility include Saga-HIMAT and i-ROCK, promoted by the Kanagawa prefectural cancer center. Toward the further sophisticated conformal carbon-ion RT with HIMAC, the NIRS has since 2006 been developing new treatment technologies, such as a fast 3D rescanning with a pencil beam and a compact rotating gantry. [Copyright &y& Elsevier]

At the Heavy Ion Medical Accelerator in Chiba (HIMAC), more than 8000 patients have been successfully treated by carbon ion beams since 1994. The successful results of treatments have led us to construct a new treatment facility equipped with a 3-D pencil beam scanning irradiation system. For the implementation of this irradiation technique, we developed a fast scanning magnet and its power supply, which are required to have field ramp rate of more than 250 T/s. The scanning magnets set at the entrance of the irradiation system are two dipole magnets to scan the beam in both horizontal and vertical directions and used to form the irradiation field to be tumor shape. Before the installation, performance test including both static and dynamic field measurement was carried out. Severe delay of the field and temperature rise were not observed as expected. Measured field ramp rate reached up to 300 T/s. After the installation, we verified the accuracy and stability of the scanned ion beam through the commissioning with the beam. As a successful result of the commissioning, treatment using the new scanning system was started in 2011. [ABSTRACT FROM PUBLISHER]

We have been developing a novel laser spectroscopy method-'OROCHI' for radioisotopes trapped in superfluid helium. This new method is expected to determine nuclear spins and moments of exotic nuclei by precise measurement of Zeeman and hyperfine splitting of atoms using laser double resonance method. Its feasibility has been confirmed by means of a series of experiments with various stable atoms in superfluid helium, while the accuracy of experimental results is found strongly affected by external magnetic field. In order to obtain reliable and accurate results for atomic spectra with 'OROCHI' method, based on laser RF double resonance spectroscopy of on-line experiment, we performed off-line test experiments for $^{85,87}$Rb in helium buffer gas. In this test experiment, we used three mutually orthogonal coils to effectively compensate for laboratory residual magnetic field and subsequently observed precise laser RF double resonance spectra of atoms which affords us accurate nuclear spin value. By comparison of those results, we could make clear the effect of residual magnetic field on experimental results. The details of 'OROCHI' method and test experiments are presented. [ABSTRACT FROM AUTHOR]

We report conclusive evidence of an efficient cooling mechanism via the electronic radiative transitions of hot small molecular anions isolated in vacuum. We stored C6- and C6H- in an ion storage ring and observed laser-induced electron detachment with delays up to several milliseconds. The terminal hydrogen atom caused a drastic change in the decay profiles. The decay of photoexcited C6H- is slow and nonexponential, which can be explained by depletion cooling, whereas that for C6- occurs extremely fast, on a time scale below 0.1 ms and can only be explained by electronic radiative cooling via low-lying electronic excited states. [ABSTRACT FROM AUTHOR]

Abstract: The effectiveness of Al addition for improvement of the corrosion resistance of ODS steel in lead–bismuth eutectic (LBE) was investigated. Al-alloying surface treatment using a GESA facility was applied to 9Cr-ODS martensitic steel, and the corrosion resistance in stagnant LBE containing 10−6 wt% oxygen was subsequently examined. Corrosion resistance of ODS ferritic steels with high Cr content (14.7wt%), containing 3.3–3.8wt% Al and small amounts of Zr or Hf, was also examined. Al-alloying surface treated 9Cr-ODS martensitic steel was tested at 650°C and ODS ferritic steels with high Cr content, containing 3.3–3.8wt% Al and small amounts of Zr or Hf, were tested at 650 and 700°C. The maximum exposure duration was 10,000h. All tested materials showed good corrosion resistance under all test conditions. Both the Al-alloying surface treatment by the GESA facility and the Al addition to the matrix with small amounts of Zr or Hf effectively improved the compatibility of ODS steel with LBE at high temperatures. [Copyright &y& Elsevier]

Abstract: The EVEDA Li test loop (ELTL) successfully completed its construction and installation of a total of 2.5-ton Li in the frame work of the IFMIF/EVEDA as one of the ITER-BA. Design for the ELTL had been done from March 2009 to December 2009 in large part, and then the construction was started on November 2009 in the O-arai site of the Japan Atomic Energy Agency and completed on the middle of November 2010 after passing an authority inspection by a fire department in O-arai town. Subsequently, the 2.5-ton Li was installed to the ELTL by using a glove box in the form of ingots which is 240mm long and 125mm in diameter. The nitrogen concentration in the 2.5-ton Li was found to be 127wppm. During the installation, the oxygen concentration and the humidity in the glove box were almost kept less than 20wppm, and any large contamination by air was prevented during the handling of Li. [Copyright &y& Elsevier]

Abstract: A fluorescent screen+a charge coupled device (CCD) system were developed to verify the performance of scanned ion beams at the HIMAC. The fluorescent light from the screen is observed by the CCD camera. Two-dimensional fields, produced by the scanning process, i.e., the position and the size of the beam for each scan, represent of the important issues in scanning irradiation. In the developed system, the two-dimensional relative fluence and the flatness of the irradiation field were measured in a straightforward technique from the luminance distribution on the screen. The position and the size of the beams were obtained from centroid computation results of the brightness. By the good sensitivity and spatial resolution of the fluorescent screen+CCD system, the scanned ion beams were verified as the measurements at the HIMAC prototype scanning system. [Copyright &y& Elsevier]

Abstract: On the basis of more than 10years of experience with HIMAC, we proposed and designed a new treatment research facility, as an extension of the existing facility, for the further development of radiotherapy with HIMAC. The new facility employs a 3D rescanning technique developed at NIRS. Its building construction was completed in March 2010 and the devices are being installed. A beam commissioning and a pre-clinical study will be initiated from this October. Here, we report recent progress for this new treatment facility project at HIMAC. [Copyright &y& Elsevier]

Abstract: In order to realize a precise dose distribution in heavy-ion cancer therapy, high beam stability is required for the accelerator complex. Owing to load fluctuation caused by the upper ring, which is one of the two rings in HIMAC, current dips of ≈5–10Hz were observed in the power supply for the bending/quadrupole magnet of the other lower ring. The parameters of the beam stability, such as the spill variation, the beam position, and the size, were adversely affected by the current dips. In order to suppress these current dips, we developed a new feed-forward system in the magnet power supply. We verified the performance of the feed-forward system by measuring the suppression of the current dips. We also performed beam experiments to measure the variation of the horizontal tune and the structure of the beam spill, which is slowly extracted by the resonance method. The experimental result showed that the current dips were successfully reduced by the system to ΔI/I ∼10−6. It was also confirmed that the horizontal tune and the spill structure could be stabilized by the current dip suppression. [Copyright &y& Elsevier]

Abstract: A flat radiation field for heavy ion beams is used in research experiments and clinical treatments. When a flat field is required, a beam spreading system must be installed for a beam line; thus a simple and affordable method is desirable. To achieve the carbon ion beam spreading, we employed a dual-ring double scattering method (DDSM), which consists of an initial scattering foil and a dual-ring subsequent scatterer. The scatterers for the DDSM were designed and tested to verify the flatness of the radiation field of the carbon ion beam. We obtained 100mm of the flat radiation field in the isocenter plane for the 2D radiation field, as expected. For the 3D radiation field, we obtained a field size of 80mm. With a 60-min setup time, using the DDSM system, and by placing only two scatterers, we can form the flat radiation field. [Copyright &y& Elsevier]

Abstract: Engineering Validation and Engineering Design Activities (EVEDA) for the International Fusion Materials Irradiation Facility (IFMIF) were started under a collaborative international project known as the ITER Broader Approach. This paper presents the design of a cold trap for reducing oxygen concentration in Li installed in a purification loop of the EVEDA Li Test Loop (ELTL). Oxygen concentration during operation of the ELTL was estimated and the cold trap is designed with reference to the design of sodium cold trap developed for fast breeder reactor research. The presumed values in this design are expected to be reevaluated through the ELTL test program by using off- and on-line impurity monitors. [Copyright &y& Elsevier]

An effective countermeasure against vibration under limitation of volume and weight of small satellites is to insert thin polyimide tape between structural elements, especially for structural vibration of a small satellite during its launch. In this study, we deal with three types of aluminum elastic beams clamped on an aluminum rigid base. To explain dynamic damping properties of thin polyimide tapes inserted between structural elements based on our experimental data, we first develop a mathematical model, which can be applied to FEM analysis. Although this model generally depends on both the number of laminated tape layers and frequency, it shall be modified to a special model, which only depends on frequency but not depend on the number of layers. Finally, using a new test beam, the validity of the proposed mathematical model is demonstrated. [ABSTRACT FROM AUTHOR]

Abstract: A key problem in the application of a supercritical carbon dioxide (CO2) turbine cycle to a fast breeder reactor is the corrosion of structural materials brought about by supercritical CO2 at high temperatures. In this study, long-term (8000 h) compatibility tests on candidate materials, two high-chromium martensitic steels (12Cr- and 9Cr-steels) and an austenitic stainless steel (316FR), were performed at 400–600 °C in supercritical CO2 pressurized at 20 MPa, and corrosion allowances for the steels were proposed for application to preliminary reactor design. Although high temperature oxidation was measured in all steels, the behavior differed greatly. For martensitic steels, weight gain exhibited parabolic growth as exposure time increased at each temperature. Neither exfoliation of the oxide nor the breakage was observed during the 8000 h of exposure. The corrosion behavior was equivalent to that seen in supercritical CO2 at 10 MPa, and it was confirmed that no effects of CO2 pressure were present under the CO2 turbine cycle operation conditions. Based on the results, corrosion allowances for temperature-dependant parabolic growth were proposed. For 316FR steel, weight gain was significantly lower than that of martensitic steels, with a maximum value of 6.2 g/m2 at 600 °C for 8000 h. Since no dependency of temperature and immersion time on weight gain such as the martensitic steels was noted, corrosion allowances proportional to time was proposed. Estimated corrosion allowances for the martensitic and austenitic steels were 380 μm and 220 μm, respectively, for reactors, whose design life is rated at 60 years. [Copyright &y& Elsevier]

The development of a microbial source tracking (MST) method is strongly desired to ensure public health and bacteriological safety in coastal recreation areas. We try to specify the source of faecal pollution by applying pulsed-field gel electrophoresis (PFGE) to the study of the aquatic environment on Aoshima Beach, Japan. Enterococcus faecium, an enterococcus, was used as a faecal indicator bacterium in this study. Enterococcus faecium strains were isolated and identified from each water sample collected from Aoshima Beach and five rivers (Oyodo, Kiyotake, Kaeda, Chifuku and Tsukunami Rivers) that might be potential sources of faecal pollution. Enterococcus faecium strains collected from water samples were analysed using PFGE. The similarities of all the PFGE types of the Ent. faecium strains were compared using dendrogram analysis. The PFGE types of the strains isolated from Aoshima Beach showed a high similarity to those of the strains isolated from the Oyodo River at a 0·9 similarity level. It was suggested that the Oyodo River is the source of faecal pollution on Aoshima Beach. The PFGE analysis using enterococci is a potential tool for the MST of faecal indicator bacteria that can be applied to the study of the coastal environment. This is one of the studies that PFGE was applied to the coastal environment. The approach using PFGE could estimate the river that is source of faecal pollution in Aoshima Beach. By applying PFGE as a tool of MST method, detailed information of faecal pollution in coastal area can be provided. [ABSTRACT FROM AUTHOR]

Abstract: Both UVB radiation and DNA-breaking agents were previously reported to kill Arabidopsis stem cells. We demonstrate that death induced by UVB or by ionizing radiation (IR) requires Suppressor of Gamma Response 1 (SOG1), a transcription factor already found to govern many responses to these agents in Arabidopsis. DNA-damage responses (DDRs) triggered primarily by replication-blocking photoadducts or double-strand-breaks thus converge to a shared programmed-cell-death (PCD) pathway. Both UVB- and IR-induced PCD also require functional DDR protein kinases. Employment of atr atm mutants (uniquely available in Arabidopsis) shows that either ATR (which recognizes ssDNA) or ATM (which recognizes DSBs) suffices for PCD induction by either agent. Thus, DNA damage made by UVB or by IR engenders both ATM-activating and ATR-activating structures. The elevated PCD in UVB-irradiated atr and atm mutants suggests that in wt plants ATR and/or ATM may activate both pathways that avert PCD and those that elicit it. The similar PCD levels induced by roughly 30,000 unrepaired photoadducts vs. 20 IR-induced DSBs indicate that DDR damage-tolerance activities in this model stem-cell niche are remarkably efficient. [ABSTRACT FROM AUTHOR]

We have been developing a new laser spectroscopic technique "OROCHI," which is based on the combination of superfluid helium as a stopper of radioactive isotope (RI) beam and in-situ laser spectroscopy of RI atoms, for determining spins and moments of exotic RIs. By using this unique technique, it is feasible to measure nuclear spins and electromagnetic moments of extremely low yield RI (estimated as less than 1 pps). Recently, we have demonstrated that nuclear spins and moments are obtained from Zeeman and hyperfine splittings of stable Rb isotopes measured using this OROCHI technique. Details of this laser spectroscopy method in He II "OROCHI" and the summary of our development are presented. [ABSTRACT FROM AUTHOR]

Abstract: In order to incorporate a procedure for the evaluation of the sodium environmental effects on core and structural materials into the elevated temperature structural design guide lines for fast breeder reactors, R&D on the sodium compatibility of the materials has been in progress in Japan Atomic Energy Agency. This paper reviews corrosion behavior in the sodium of conventional austenitic and ferritic steel. Simultaneously, the corrosion and mechanical properties of the materials for advanced FBRs, 12Cr steel and ODS steels are summarized, including the results of recent research. [Copyright &y& Elsevier]