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SUMMARY: This paper presents the development results of a −1 MV dc filter and dc measurement systems for an ITER (International Thermonuclear Experimental Reactor) neutral beam injector (NBI) system. High accuracy of 0.5% and fast responsivity of 3.3 μs, −3 dB are required for the dc measurement systems: both dc voltage dividers and DCCTs. Circuit design and thermal flow design were carried out to clarify and minimize their effects on the accuracy and responsivity. The validity of the established design was demonstrated by the actual‐product tests; temperature rise of each components fell below the allowable value; inner components of dc filter withstood dc −1.2 MV; each voltage divider accurately measured the voltage during the dc −1.2 MV withstand voltage test; the voltage dividers and the DCCTs were adequate to the requirements of responsivity (3.3 μs, −3 dB). [ABSTRACT FROM AUTHOR]

SUMMARY: This paper presents development results of a five‐stage DC‐1MV Ultrahigh Voltage Generator for ITER. Each generator outputs −200 kV, and the total five generators are connected in series and outputs −1 MV. In order to realize the DC‐1MV output and 1‐h continuous operation, a feasibility of both gas insulation and gas cooling for semiconductor devices was validated. A simplified structure with stud‐type diodes and heatsinks resulted in the compatibility of enough insulation distance and wide cooling surface. Withstand voltage tests and a temperature rise test were performed for the actual equipment of the rectifier and the step‐up transformer. These test results verified the validity of the proposed design. [ABSTRACT FROM AUTHOR]

Doxapram is the only dedicated respiratory stimulant used to aid recovery of breathing after major surgery. Doxapram acts on peripheral chemoreceptors and although the central action of doxapram has been suggested, its detailed neuronal mechanism is unknown. We assessed doxapram-induced changes in spontaneous cervical nerve (C4) inspiratory activity and the firing of action potentials in pre-inspiratory and inspiratory neurones in the medulla. Experiments were performed in neonatal rat brainstem-spinal cord preparations, which can produce respiratory rhythm for several hours under in vitro conditions. Doxapram application (for 15 min) increased the frequency and amplitude of C4 activity dose-dependently. Doxapram induced changes in the electrophysiological properties of pre-inspiratory and inspiratory neurones. Our results suggest that respiratory activity enhancement was likely to be induced via effects on the potassium channels of pre-inspiratory and inspiratory neurones and indicate the central actions of doxapram. [ABSTRACT FROM AUTHOR]

Hatching responses of the Japanese whiting, Sillago japonica Temminck et Schlegel, to a series of temperature changes were measured by exposing the fertilized eggs to eight constant incubation temperatures which ranged from 20.0 to 34.0°C. For a control, hatching temperature was kept the same as temperature of the ambient environment. Hatching responses were expressed as hatching percentages. Altogether 18 experimental trials were conducted during the natural spawning season of the species which extended over a period of 2 months from late July to mid-September 1988, when seawater temperature varied between 24.0 and 30.0°C. Optimum and limiting temperatures were recorded and the data were optimally fit to the quadratic model. Results indicated that viable hatch occurred at almost all ranges of hatching temperature from 22.0 to 32.0°C. However, no hatching was recorded at either 20.0 or 32.0°C. The experiment showed that the optimum hatching temperature varied with the ambient temperature changes during the spawning season, indicating the latter to be a dependent factor for any hatching success. [ABSTRACT FROM AUTHOR]

Background The major underlying mechanisms contributing to acute coronary syndrome are plaque rupture, plaque erosion, and calcified nodule. Artery-to-artery embolic myocardial infarction (AAEMI) was defined as ST-segment-elevation myocardial infarction caused by migrating thrombus formed at the proximal ruptured plaque. The aim of this study was to investigate the prevalence and clinical features of AAEMI by using optical coherence tomography. Methods and Results This study retrospectively enrolled 297 patients with ST-segment-elevation myocardial infarction who underwent optical coherence tomography before percutaneous coronary intervention. Patients were divided into 4 groups consisting of plaque rupture, plaque erosion, calcified nodule, and AAEMI according to optical coherence tomography findings. The prevalence of AAEMI was 3.4%. The culprit vessel in 60% of patients with AAEMI was right coronary artery. Minimum lumen area at the culprit site was larger in AAEMI compared with plaque rupture, plaque erosion, and calcified nodule (4.0 mm 2 [interquartile range (IQR), 2.2-4.9] versus 1.0 mm 2 [IQR, 0.8-1.3] versus 1.0 mm 2 [IQR, 0.8-1.2] versus 1.1 mm 2 [IQR, 0.7-1.6], P <0.001). Lumen area at the rupture site was larger in patients with AAEMI compared with patients with plaque rupture (4.4 mm 2 [IQR, 2.5-6.7] versus 1.5 mm 2 [IQR, 1.0-2.4], P <0.001). In patients with AAEMI, the median minimum lumen area at the occlusion site was 1.2 mm 2 (IQR, 1.0-2.1), 40% of them had nonstent strategy, and the 3-year major adverse cardiac event rate was 0%. Conclusions AAEMI is a rare cause for ST-segment-elevation myocardial infarction and has unique morphological features of plaque including larger lumen area at rupture site and smaller lumen area at the occlusion site.

Background: Application of speckle-tracking echocardiography (STE) provides rapid assessment of tissue-tracking mitral annular displacement (TMAD). We investigated the value of TMAD for the assessment of decreased LV longitudinal deformation in asymptomatic patients with severe or moderate-to-severe mitral regurgitation (MR) and preserved LV ejection fraction (LVEF)., Methods: We retrospectively studied 50 patients with severe or moderate-to-severe organic MR and preserved LVEF (>60%) in whom global longitudinal strain (GLS) was successfully measured by STE. TMAD was quickly assessed in the apical four-chamber view using STE. We calculated the percentage of TMAD to LV length from the midpoint of mitral annulus to the apex at end-diastolic (%TMAD). The study population was divided into two groups: decreased GLS patients (>-20%; Group A) and preserved GLS patients (≤-20%; Group B). We examined whether %TMAD could be used as a diagnostic factor of decreased GLS., Results: %TMAD was significantly lower in Group A than Group B (12.5 ± 0.5 vs 16.8 ± 2.2, P < 0.0001). By univariate logistic regression analysis, %TMAD was a diagnostic factor of decreased GLS. By multiple regression analysis, %TMAD remained an independent diagnostic factor of decreased GLS (Odds ratio [OR] = 4.21, 95% confidence interval [CI] = 1.34-28.94, P < 0.0001). A cutoff value of %TMAD <14.6 had a sensitivity of 94% and specificity of 94% for the presence of decreased GLS., Conclusions: Tissue-tracking mitral annular displacement is useful in the assessment of decreased LV longitudinal deformation in asymptomatic patients with severe or moderate-to-severe MR and preserved LVEF., (© 2019 Wiley Periodicals, Inc.)

Background: Assessment of right ventricular (RV) function remains challenging because of its complex geometry. Application of speckle-tracking echocardiography (STE) to the tricuspid annulus provides rapid and automated assessment of the midpoint of the tricuspid annular plane displacement (TAD). The aim of this study was to investigate the value of tissue-tracking TAD for the assessment of RV systolic dysfunction., Methods: We retrospectively studied 61 patients in whom RV ejection fraction (EF) measured by 3-dimensional echocardiography was performed. STE-derived displacement of the midpoint between the septal and lateral tricuspid annulus and its percentage of RV length at end-diastole (MTAD) were automatically assessed. We performed comparative analyses between the RVEF ≥45% group and the RVEF <45% group in each parameter for the assessment of RV systolic function., Results: MTAD was successfully assessed in 56 (91.2%). According to receiver operating characteristics analysis, RVEF <45% was best detected by MTAD <14.7% with area under curve (AUC) 0.97, sensitivity 93%, specificity 95%, followed by RV free wall longitudinal strain (AUC 0.86), RV fractional area change (AUC 0.84), tricuspid annular plane systolic excursion (AUC 0.79), and systolic peak velocity of tricuspid annulus (AUC 0.70), although there was no significant difference between MTAD and RV free wall strain (P = 0.14)., Conclusion: The present study showed that MTAD was simple index and useful for the assessment of RV systolic dysfunction., (© 2018 Wiley Periodicals, Inc.)

1. Propofol (2,6-diisopropylphenol) is an intravenous anaesthetic used for the induction and maintenance of general anaesthesia; it also potently and dose-dependently depresses respiration. The aim of the present study was to analyse propofol-induced changes in spatiotemporal patterns of inspiratory-related neural activity and to investigate the involvement of the GABAA receptor by using an optical imaging technique. 2. The brain stems and spinal cords of 0-1-day-old Wistar rats were isolated and stained using a fluorescent voltage-sensitive dye. Neuronal activity in the preparation was detected using an optical recording apparatus containing a charge-coupled device (CCD)-based camera. 3. Bath-applied propofol (7.5 μmol/L) decreased the C4 burst rate to 45.9% of baseline. Although optical signals corresponding to membrane depolarization during the pre-inspiratory phase in the parafacial region of the ventral medulla decreased to 28.7% of baseline following propofol application, those during the inspiratory phase in the caudal part of the rostral ventrolateral medulla did not. 4. The inhibitory effect of bath-applied propofol was reversed by 2 μmol/L bicuculline. 5. Changes in optical signals corresponding to the population activity of pre-inspiratory neurons were parallel to changes in the C4 burst rate. 6. The results suggest that propofol decreases the inspiratory burst rate by reducing the activity of pre-inspiratory neurons and that GABAA receptor activation plays a role in propofol-induced central respiratory depression. These results are consistent with those of previous electrophysiological studies., (© 2011 The Authors. Clinical and Experimental Pharmacology and Physiology © 2011 Blackwell Publishing Asia Pty Ltd.)