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Rationale: Recent studies have shown that QT interval prolongation is associated with disease severity and predicts mortality in systemic inflammatory diseases, particularly rheumatoid arthritis. Systemic pro-inflammatory cytokines released from synovial tissues in rheumatoid arthritis, such as interleukin (IL)-1β, IL-6, and tumor necrosis factor-α, could have direct effects on cardiac electrophysiology, particularly changes in the expression and function of potassium and calcium channels, resulting in QT interval prolongation on surface electrocardiogram (ECG) and an increased predisposition to develop lethal ventricular arrhythmias. However, reports on torsade de pointes (TdP) due to acquired long QT syndrome in patients with polymyalgia rheumatica (PMR) are limited. Patient concerns: An 85-year-old Japanese woman with active PMR developed first syncope. Diagnosis: Frequent premature atrial contractions (PACs) with multiple patterns of aberrant conduction, QT interval prolongation, and morphological T-U wave variability followed by TdP were documented. PACs were the first beat of TdP. Interventions: Amiodarone, together with magnesium and potassium, was intravenously administered. However, TdP resulted in a ventricular arrhythmic storm, for which sedation with mechanical ventilatory support, temporary overdrive cardiac pacing, and intravenous landiolol administration in addition to multiple direct current shocks were effective. Outcomes: Approximately 2 years later, the patient was treated with amiodarone, propranolol, and prednisolone. She did not undergo implantable cardioverter-defibrillator implantation and was quite well, with no recurrence of ventricular tachyarrhythmia. Lessons: IL-6 hyperproduction in inflamed tissues has been widely confirmed in PMR. Frequent PACs with various patterns of aberrant conduction, QT interval prolongation, and morphological T-U wave variability followed by TdP, for which IL-6-mediated enhancement of L-type Ca2+ current and inhibition of the rapid component of the delayed rectifier K+ current are the most likely mechanisms, were documented in an elderly Japanese woman with PMR. ECG may be recorded once in patients with active PMR even when these patients do not complain of palpitation or syncope. If QT interval prolongation or arrhythmia, including even PACs, is observed, follow-up ECG may be warranted, particularly for patients with some risk factors for QT prolongation that could lead to TdP, such as advanced age, female sex, hypopotassemia, and polypharmacy.

Secondary-side center-tapped transformers are widely utilized for high step-down forward DC-DC converters. For reducing the copper loss, optimization of the winding layer allocation can be a promising approach. However, the optimal allocation pattern has been difficult to be elucidated, particularly if the winding is formed of parallel-connected winding layers or carries the AC and DC current as in a center-tapped winding. This difficulty is addressed in this paper by proposing a copper loss analysis method applicable to parallel-connected winding layers and a center-tapped winding. The proposed analysis method utilizes the Dowell method in combination with the extremum co-energy principle, which has been recently proposed to analyze the current distribution in parallel-connected winding layers. As an example, this paper analyzes the center-tapped transformer each secondary winding of which is made of two parallel-connected winding layers. The optimal winding layer allocation pattern was elucidated by comparing the copper loss among six possible winding layer allocation patterns. Appropriateness of the analysis was verified by simulation, suggesting the effectiveness of the proposed method and the importance of optimizing winding layer allocation in the forward transformer design.

Insulated AC/DC converters using matrix converters (MCs) have higher efficiency, smaller size, and longer lifespan compared with conventional ones. For downsizing of high-frequency (HF) transformers in these converters, developments of HF output MC control methods are active. It is expected to improve efficiency by applying soft switching techniques for these converters. However, to achieve soft switching, phase difference between an output voltage and a current is required. As a result, output power factor decreases. In this paper, a relationship between soft switching conditions and output power factor is revealed. Considering this relationship, the authors propose a new MC control method to achieve soft switching and maximum output power factor. Additionally, this method enables to suppress the distortion of input currents and reduce ripple of the output current. Also, the MC can control the output current and instantaneous reactive power. The authors confirm that experimental results show validity of the method.

Computer investigation and design of light propagation in fluorescent scattering media is considered. Suggested solution provides efficient and physically accurate model of light propagation in the media that allows simulating Stokes color shift effect and design of white LED. Based on the suggested solution the program package of simulation and design of optical devices with fluorescent scattering media was implemented and trial design of white LED was fulfilled.

The approach for autodesign of optical characteristics of different illumination units such as backlight systems, led arrays and light boxes is considered. Suggested software solution allows finding optimal configuration of lighting scheme for providing necessary distribution of output light. Additional preprocessing phase is introduced in design process, which provides reduction of design iterations and better convergence compared to conventional design methods, utilizing random fluctuations of design parameter between iterations. The results of several designs of different kinds of illumination systems are presented.

This paper proposes a new control method for three-phase to high-frequency single-phase matrix converter (MC) based on instantaneous input voltages. Direct conversion of AC input power to AC output power by MC resulting in higher conversion efficiency, longer lifespan, and more compact size compared to the conventional method by using PWM rectifier and PWM inverter. The proposed MC can produce high frequency output equal to its power devices' switching frequency. The feature of the proposed control method is its sophisticated calculation based on instantaneous input voltages, producing unity input power factor and regulating the output voltage according to the reference value at any instant. Some simulation and experiment results are shown to prove the validity and effectiveness of the proposed method.

Modern roll stabilization system, namely fin, anti-roll tank and rudder action are used respectively or in combination on most passengers and naval ships. This paper proposes the advanced rudder roll stabilization control system with fin control. Fin and rudder multivariate hybrid control system were designed using multivariate autoregressive model with multi-input (yaw and roll motion) and multi-output (rudder and fin angle), named MAFRCS (Multivariate Autoregressive Fin and Rudder hybrid Control System). This paper presents the results of studies which led to the development of performing mode of operation for this hybrid control system which system has full control of rudder while fin automatically reduce the roll motion and keep the yaw motion. The results of full scale experiments and simulations studies were given to illustrate the system performances.

動脈性出血による吐血,貧血をきたし,緊急手術を要した胃悪性リンパ腫の1例を経験したので報告する.症例は66歳,男性.主訴:吐下血,上腹部痛. 2002年1月29日上腹部痛,嘔気,吐血出現し, 30日当センター受診.貧血(Hb 10.2g/dl)認め,緊急上部消化管内視鏡検査施行.胃体部前壁に2型腫瘍と同部からの動脈性出血を認め,内視鏡的止血術を試みるも完全止血は得られず,貧血の進行を認めたため,同日緊急手術を行った.リンパ節郭清(D2)を伴う胃全摘術+脾摘術施行した.摘出標本上,胃体部前壁に7.0×4.2cm大の隆起性腫瘤と小彎側のIIc病変認め,病理ではgastric lymphoma, diffuse large cell type, mp, n 0 (0/82)であった.出血部位には表層に露出破綻した動脈を認めた.術後経過は良好で15日目に退院,現在外来通院中である.消化管悪性リンパ腫に対しても,緊急手術療法が必要となる稀な症例も存在しうる.

The combination of fin and rudder seems to be an attractive alternative for roll damping. However fin motions as well as high frequency rudder motions disturb the heading control system. In order to reduce this interaction, this paper proposes the advanced rudder roll stabilization control system with hybrid fin control system. From results of simulation and model experiments, it can be concluded that the fin and rudder hybrid control system is powerful and useful tool for stabilization of roll and course keeping.

Direct Drive Volume Control Hydraulic Servo System (DDV System) is the system which can control the position of actuator with controlling the revolution of hydraulic pump directly.This system is known that it can decrease energy consumption because the pump is driven only when the motion of actuator is required. It does not has a transient phenomena such as surging because the change of actuator motion is carried out with changing the direction of pump revolution. It can make the size of system very small, because heat loss of the system is small and it does not require a large size of oil tank for cooling. Many kinds of hydraulic system are used in a ship. One of the most important system is steering system and we adopted the DDV system to “Shioji-maru” which is the training ship of Tokyo Univ. of Mercantile Marine. The results of this study was excellent ; the size of hydraulic source system become less than 1/10, energy consumption become under 1/20 and surging is eliminated.Considering those results, the authors are trying to apply this system to anti-rolling system with rudder or fin stabilizer.