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A Sillén SrBi3O4Cl3 is synthesized in pure and high-crystallinity form via a flux method with an appropriate molten salt, which leads to a higher photocatalytic activity than that of SrBi3O4Cl3 prepared by a conventional solid-state reaction method.

The article discusses the musical idea of Vytautas Bacevičius, which he called “cosmic music”. The composer put it forward in the 1960s–1970s, i.e., in the latest period of his life. During this period, he composed the orchestral work Graphique, op. 68. The article aims to reveal how his idea of cosmic music manifests itself in the aforementioned work. Bacevičius used a graphic score in the process of composition of the work. By using it, the composer aimed to transcend the conventional way of musical representation and to realise his idea of cosmic music. Various factors that are implicated, such as Adomas Galdikas’s (1893–1969) painting, Edgard Varèse’s (1883–1965) music, Claude Bragdon’s (1866–1946) philosophy, should also be taken into account. The analysis of Graphique shows explicitly that these factors are closely related to the means of composition used in the work, i.e., sonoristic textures. They reveal not only Bacevičius’s attention to timbres and acoustics, but also the synaesthetic idea, which can be considered a manifestation of his cosmic music.

The frozen elephant trunk (FET) procedure enables easier replacement of the entire aortic arch because it does not require reaching the distal part of the left subclavian artery (LSCA). However, it requires additional management for reconstruction of the LSCA, which is associated with bleeding events. However, the fenestrated FET technique confers a risk of endoleakage from the fenestration site. We report our unique novel technique in which the proximal side of the hybrid stent graft is cut into V-shape around the subclavian artery and sutured continuously around the orifice of the subclavian artery during aortic stump fixation.

We carried out repeated excitation experiments of a test magnet for accelerator applications of RE-123 coated conductors in order to study its tolerance against ac loss and the stability as well as the reproducibility of the generated magnetic field. The magnet consists of a pair of 4-stacked racetrack coils with an iron return yoke in the low temperature region. It can generate 2.4 T of dipole magnetic field at its room temperature beam duct with its rated current of 200 A, and the maximum magnetic field to which the coated conductor is exposed is about 4 T. At first, the magnet was excited repeatedly with a saw-tooth waveform to examine the tolerance against ac loss: the magnetic field was ramped up to 4 T at the conductor in 120 s and down to 0 T in 120 s. We also carried out numerical electromagnetic field analyses to estimate the ac loss in the magnet. Next, we examined the influence of shielding currents on the field stability and reproducibility at the steps during ramping down, where the current was held constant. This simulated the excitation pattern of magnets for carbon gantries.

A cryocooler-cooled high-temperature superconducting magnet was constructed, and it was tested on the beam line of the heavy ion medial accelerator in Chiba (HIMAC). The magnet consists of a pair of four-stacked racetrack coils wound with RE-123 coated conductor that are plated with 41- μ m copper for protection. The magnet has a room temperature beam duct, at which 2.4 T of magnetic field is generated, whereas the maximum magnetic field to which coated conductors are exposed is approximately 4 T. The magnetic field in the beam duct was measured and calculated to examine its stability, which might have been affected by shielding currents in the coated conductors. On the beam line of the HIMAC, at first, the beam guiding by the magnet was demonstrated. The measured beam-guiding characteristics were compared with the beam tracking calculations. Next, a carbon ion beam was injected intentionally into the RE-123 coils of the magnet to simulate the incidents of uncontrolled beam injection into accelerator magnets. Prior to this test, the possible heat deposition to the coil by the beam injection was calculated, and the feasibility of quench protection using a dump resistor was studied through quench experiments using short pieces of the RE-123 coated conductors.

When superconducting magnets are operated in a conduction-cooling system, if a malfunction of the cryocooler or an abnormality in the heat transfer path occurs, the temperature of the coil increases. In most cases, the operating temperature limit is designed so that thermal runaway of the coil can be prevented by charging-down or shutdown of the magnet. Therefore, the temperature margin should be considered carefully. In this research, a bypass circuit for a REBCO coil was developed using the flux flow resistance generated inside the coil when the load factor rises. Low resistors were connected to both ends of a test coil composed of a stack of four single pancakes wound with 4-mm-wide REBCO tape having an inner diameter of 200 mm and an outer diameter of 291 mm in the cryostat. Automatic suppression of the current flowing through the coil at high load factor was attempted. In this report, the test and simulation results of the coil operation when the cryocooler was intentionally stopped under conduction-cooling conditions are compared and discussed.

An R&D project funded by the Japan Science and Technology Agency under its S-Innovation Program is currently in progress. The purpose of this project is to develop fundamental technologies for accelerator magnets with REBCO coils. In the first step of this project, winding technology for fabricating REBCO coils required for HTS accelerator magnets was developed. At the last stage of this project, there are plans to fabricate cryocooler-cooled REBCO magnets and evaluate the beam guiding characteristics and stability against beam injection to the magnets at the beam line of Heavy Ion Medical Accelerator in Chiba (HIMAC). This paper describes the design of an HTS magnet fabricated for this evaluation and presents fabrication results of this magnet. The magnet had a room-temperature beam duct with dimensions 264× 40 mm for beam guiding. The magnet consisted of a pair of racetrack coil stacks each containing four coils, and a cold iron was adopted to increase the magnetic field strength. It could generate a dipole field of 2.4 T at the beam duct by 200 A excitation. Furthermore, beam windows were placed on the side of the cryostat for beam injection tests, allowing the beam to irradiate the REBCO coil directly.

A 68-year-old woman who had been well for 2 years after ascending aortic graft replacement experienced sudden chest pain. Computed tomography showed a large false aortic aneurysm around the prosthesis. However, the patient was hemodynamically stable and did not have anemia. Emergency surgery under hypothermic circulatory arrest revealed tears at both the proximal and distal anastomotic sites and blood circulating from the proximal (exit) to the distal (entry) tears underneath the pericardium. To our knowledge, the present case represents a previously unreported pathology that will be of great interest to cardiologists and cardiac surgeons.

We carried out repeated excitation experiments of a test magnet for accelerator applications of RE-123 coated conductors in order to study its tolerance against ac loss and the stability as well as the reproducibility of the generated magnetic field. The magnet consists of a pair of 4-stacked racetrack coils with an iron return yoke in the low temperature region. It can generate 2.4 T of dipole magnetic field at its room temperature beam duct with its rated current of 200 A, and the maximum magnetic field to which the coated conductor is exposed is about 4 T. At first, the magnet was excited repeatedly with a saw-tooth waveform to examine the tolerance against ac loss: the magnetic field was ramped up to 4 T at the conductor in 120 s and down to 0 T in 120 s. We also carried out numerical electromagnetic field analyses to estimate the ac loss in the magnet. Next, we examined the influence of shielding currents on the field stability and reproducibility at the steps during ramping down, where the current was held constant. This simulated the excitation pattern of magnets for carbon gantries.

A research and development project to reduce the weight of a rotating gantry for carbon ions using high-temperature superconducting (HTS) magnets started in 2013, supperted by the Japanese Ministry of Economy, Trade and Industry (METI) and the Japan Agency for Medical Research and Development (AMED). In this project, we aim to develop fundamental technologies for designing and fabricating a HTS gantry, and fabricate a small model of a HTS dipole magnet and evaluate its performance. The results of the project are described in this paper.

With the aim of verifying the winding technology required for fixed-field alternating gradient (FFAG) accelerator magnets, and also to verify the magnetic field accuracy as compared with the designed field distribution, a reduced-size test magnet, referred to as a “model magnet,” has been developed. The model magnet was designed to incorporate multiple REBa2Cu3Ox (REBCO) coils with characteristic shapes, namely negative bend parts and 3-D winding shapes, derived from a full-scale spiral-sector FFAG accelerator design which was accomplished in this study. The coils were wound using 4-mm-wide REBCO-coated conductors made by the ion-beam-assisted deposition metal organic chemical-vapor deposition method, and the total length of the conductor for the model magnet was about 2000 m. After winding, the coils were installed in heat-conduction shells made of an aluminum alloy and were directly cooled by a Gifford-McMahon (GM) cryocooler in a vacuum vessel. It was essential to wind the REBCO coils without degradations, such as local delamination of the superconducting layer, because the voltage generated at such degraded parts frequently increases during operation, and eventually results in thermal runaway. The superconducting properties of all coils were verified before and after installing them in the aluminum shells. This paper describes the assembly of the REBCO coils, as well as testing procedures and test results of the model magnet.

We designed a coil-dominated magnet wound with coated conductors for a spiral sector fixed-field alternating-gradient (FFAG) accelerator for carbon cancer therapy. The magnet consisted of deformed pancake coils with negative bends. Coils were arranged similar to a ladder to generate the required radial profile of magnetic field. The positions and the number of turns of the coils were iteratively adjusted to reduce the magnetic field error. We carried out numerical electromagnetic field analyses of the designed magnet to evaluate the influence of coated-conductor magnetization (screening or shielding current) on its field quality.

A project to develop fundamental technologies for accelerator magnets using high- $T_{c}$ superconductors is currently underway. In this project, conceptual design studies of fixed-field alternating gradient (FFAG) accelerators for carbon cancer therapy and for accelerator-driven subcritical reactors have been carried out. To establish technologies for cryocooler-cooled high- $T_{c}$ superconducting (HTS) accelerator magnets wound with coated conductors, a downscaled model magnet system for a spiral-sector FFAG accelerator has been developed. A model magnet consisting of multiple coils with complicated shapes, including a negative-bend part or a 3-D bent part, was designed to demonstrate the generation of an asymmetrical magnetic field on the midplane of the magnet bore. One issue is how to wind coils for the accelerator magnets by using tape-shaped coated conductors, which have anisotropic bending flexibility between the flatwise and edgewise directions. Another issue is the effects of the characteristic features of the coated conductors on the accuracy of the magnetic field. The field precision of coils wound with coated conductors is considered to be influenced by the dimensional accuracy of the YBCO tapes and coils, as well as the magnetization of the HTS layer. This paper describes the design and fabrication of YBa2Cu3Ox coils for the model magnet, as well as disturbance factors of the field of the HTS magnet and the effect of dimensional variations of the YBCO coil on the magnetic field.

The effectiveness of heavy-ion radiotherapy for cancer treatment has been recognized by medical experts and the public. However, due to the large size of the equipment, this therapy has not been widely adopted. In particular, the rotating gantries used to irradiate patients with the heavy-ion beams from any direction may be as heavy as 600 tons in our estimation. By employing high-temperature superconducting (HTS) wires in these rotating gantries and increasing the magnetic field generated by the deflecting coils, the total weight of the rotating gantry can be reduced to around the weight of those used for proton radiotherapy. A project for developing an HTS deflecting magnet for heavy-ion radiotherapy has been underway since 2013, supported by the Japanese Ministry of Economy, Trade and Industry (METI) and the Japan Agency for Medical Research and Development (AMED). The aim of this project is to develop fundamental technologies for designing and fabricating HTS deflecting magnets, such as irregular magnetic field estimating techniques, design technology for HTS magnets, high-precision HTS coil winding technology, AC loss estimating techniques, and thermal runaway estimating techniques and to fabricate a small model of an HTS deflecting magnet and evaluate its performance. In this paper, the project's progress will be described.

Background The NU-FLASH trial demonstrated that febuxostat was more effective for hyperuricemia than allopurinol. This time, we compared these medications in patients with chronic kidney disease (CKD) from the NU-FLASH trial. Methods and results In the NU-FLASH trial, 141 cardiac surgery patients with hyperuricemia were randomized to a febuxostat group or an allopurinol group. This study analyzed 109 patients with an estimated glomerular filtration rate (eGFR) ≤60 mL/min/1.73 m2, and also analyzed 87 patients with stage 3 CKD. The primary endpoint was the serum uric acid level. Secondary endpoints included serum creatinine, urinary albumin, cystatin-C, oxidized low-density lipoprotein, eicosapentaenoic acid/arachidonic acid ratio, total cholesterol, triglycerides, low-density lipoprotein, high-density lipoprotein, and high-sensitivity C-reactive protein. Among patients with an eGFR ≤ 60 mL/min/1.73 m2, uric acid levels were significantly lower in the febuxostat group than the allopurinol group from 1 month of treatment onward. The serum creatinine, urinary albumin, cystatin-C, oxidized low-density lipoprotein, eicosapentaenoic acid/arachidonic acid ratio, and high-sensitivity C-reactive protein were also significantly lower in the febuxostat group. Similar results were obtained in the patients with stage 3 CKD. Conclusion In cardiac surgery patients with renal dysfunction, febuxostat reduced uric acid earlier than allopurinol, had a stronger renoprotective effect than allopurinol, and also had superior antioxidant and anti-inflammatory effects.

Background: Based on the revised AHA/ACC guidelines, it might be necessary to take into consideration the average life expectancy of Japanese people and revise the Japanese guidelines accordingly. Accordingly, we performed the present study to compare the long-term outcome in patients aged 65 years or older who underwent prosthetic valve replacement at our hospital using mechanical valves or biological valves. Methods: We have performed valve replacement in 416 patients aged 65 years or older (mechanical: 157; biological: 244). Results: There was no significant difference between the mechanical and biological valve for the actuarial survival rate. As for the valve-related complication free rate, in the mechanical valve group, the rates were significantly higher for all patients, aortic valve replacement (AVR) patients, and mitral valve replacement (MVR) patients. Conclusions: Following revision of the AHA/ACC guidelines for selection of prosthetic valves, it is necessary to investigate whether patients aged 60–70 represent the gray zone for selecting valves as in US and European guidelines, or whether a higher age is more appropriate in view of the longer average life expectancy in Japan. Accordingly, further evaluation of the long-term outcome for mechanical and biological valves in Japanese patients is needed to obtain evidence for preparation of original Japanese guidelines on prosthetic valve selection.

In this paper, we consider the transition process of a disaster prevention consciousness and action as a disaster subculture, and present an analytical framework using a mathematical simulation in order to enable quantitative consideration. After an unknown parameters estimation by using a questionnaire survey data, we describe the actual situation in this simulation model, and evaluate an influences imparted to the population ratio of four states related with the disaster prevention consciousness and action by some explanatory variables such as a force of contagion, a move-out ratio, and so on. As a result, we receive valuable suggestions that it is impossible to avoid a fading of the disaster prevention consciousness, and that it is possible to vitalize the disaster prevention action continuously if some social conditions are satisfied. Language: ja

A newly designed racetrack coil wound with REBCO-coated conductor was developed and demonstrated. The coil shape was improved to achieve consistent dimensional accuracy, and the winding structure was improved to prevent degradation in the epoxy-impregnated windings. The wire length of the fabricated large-scale coils was 574 m, and the overall size was 434 mm × 796 mm. This wire length was longer than that of any of the coils the authors fabricated previously. The outer radiuses in both the semicircular sections and the pseudo-straight sections, which had a slight curvature, were approximately the same in the two coils, to within 1 mm, indicating that good dimensional accuracy was obtained consistently. Furthermore, the n-value was sufficiently high at 24 in an electric field range from 10- 9 to 10- 7 V/cm at 77 K, which indicates that the coils had no damaged area in the windings.

A radial stress is generated in the winding when an impregnated YBCO pancake coil is cooled from room temperature to 77 K or less. If this radial stress locally exceeds the delamination strength of the YBCO-coated conductor under transverse tensile stress, the coil will be degraded. Although several methods for evaluating the delamination strength of YBCO-coated conductors have been reported, the delamination strength determined by these methods has shown considerable variation. In order to fabricate an impregnated coil that does not suffer from degradation, it is important to determine the exact delamination strength. The delamination strength was evaluated using small impregnated test coils with an inner diameter of 30 mm and an outer diameter from 36 mm to 60 mm, since the radial stress depends on the ratio of inner to outer diameter regardless of the coil size. The delamination strength can be obtained by investigating the ratio of inner to outer diameter that does not result in degradation. On the other hand, for a larger ratio of inner to outer diameter, it is necessary to make the radial stress less than the delamination strength of the YBCO-coated conductor. To achieve this, the radial stress was decreased by dividing the coil into a number of parts in the radial direction.

A 67-year-old man who had undergone substernal gastric tube interposition due to esophageal cancer showed ST changes on electrocardiography. Diagnosis was severe stenosis of the left anterior descending branch that required emergency coronary artery bypass grafting. Preoperative computed tomography (CT) showed the feeding arteries of the gastric tube were in contact with the left internal mammary artery. Therefore, we felt harvesting this artery could be dangerous and decided to perform a median sternotomy, approaching from the right side of the gastric tube. The pericardium was easily and safely reached. We undertook on-pump cardiac arrest single coronary artery bypass grafting of the left anterior descending artery with a saphenous vein graft. The postoperative course was uneventful without mediastinitis. Cardiac surgery after esophageal cancer is often performed from a left thoracotomy. But, we recommend a median sternotomy be performed as an option. Preoperative contrast-enhanced CT should be considered as it may indicate the need for a significant revision such as a median sternotomy.

The 7-endo Friedel–Crafts cyclization of vinyloxiranes, which have a nitrogen atom at the linker between the aromatic ring and the epoxide, was found to proceed regio- and stereoselectively to afford polyfunctional tetrahydro-1-benzazepine and tetrahydro-2-benzazepine.