433 research outputs found

    Relation between ventriculoarterial coupling and myocardial energetics in patients with idiopathic dilated cardiomyopathy

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    AbstractObjectives. The purpose of this study was to evaluate left ventricular contractility, arterial loading conditions and the way their interaction affects myocardial energetics.Background. Ventriculoarterial coupling, defined as the ratio of effective arterial elastance to left ventricular end-systolic elastance, is known to reflect the mechanoenergetic performance of the heart. However, relations between the coupling and efficiencies of energy transfer from oxygen consumption to hydraulic energy have not been fully investigated in failing hearts.Methods. Pressure-volume data were measured in 23 patients with idiopathic dilated cardiomyopathy by using a conductance catheter, and myocardial oxygen consumption was obtained simultaneously in 16 patients by a double-thermistor coronary sinus catheter. End-systolic elastance was determined by transient inferior cava occlusion.Results. Data are reported as mean value ± SE. Ventriculoarterial coupling at baseline was 3.14 ± 0.28. It decreased from 3.12 ± 0.43 to 1.86 ± 0.15 (p < 0.05) for the group receiving dobutamine infusion and from 3.16 ± 0.45 to 1.78 ± 0.22 (p < 0.01) for the group receiving the oral phosphodiesterase inhibitor MS-857. The ratio of pressure-volume area to myocardial oxygen consumption had a positive correlation with ventriculoarterial coupling. The ratio of external work to pressure-volume area had a hyperbolic correlation with the coupling. The mechanical efficiency defined as the ratio of external work to myocardial oxygen consumption remained within a narrow range (16.4 ± 1.2%).Conclusions. The degree of ventriculoarterial coupling is far from optimal and the cardiovascular performance is severely depressed mechanically and energetically in patients with idiopathic dilated cardiomyopathy. Although inotropic agents improve the coupling, they have a minimal effect on mechanical efficiency

    Japanese university students' behavior when reading english: a questionnaire survey and factor analysis

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    This paper reports on a specific cognitive behavior often found when trying to understand a text not written in readers’ native language. Our research group conducted a questionnaire survey to examine Japanese readers’ cognitive behavior and awareness when reading English texts. We also conducted a factor analysis on this questionnaire to identify the behaviors often found when reading English. Participants were 56 Japanese students studying engineering at Chuo University. After reading the texts, a questionnaire consisting of 43 items was applied to the participants. We used exploratory factor analysis to identify the primary factors related to readers’ cognitive behavior and awareness when reading a non-native language. As a result of the analysis, mainly based on the highest contributing factors, it was suggested that readers may have made substitutions into Japanese, their own words, when reading the English texts. In other words, when reading a non-native language, the reader may read the texts by replacing them with their native language rather than comprehending it in that language. Based on the results of our experiment, it is expected that the research on the cognitive supporting systems may help readers to understand non-native languages quickly and smoothly

    Systems and Methods for Inspecting Coatings

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    A system for detecting defects in paint coatings includes a temperature manipulation apparatus configured to change the temperature of a surface and a coating applied to the surface. The system may further include an infrared sensor for measuring the change in temperature of the surface and coating and a processor to compare the measured change in temperature of the surface and coating to an expected change of temperature in order to determine anomalies in the coatings

    Reduction of thermal fluctuations in a cryogenic laser interferometric gravitational wave detector

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    The thermal fluctuation of mirror surfaces is the fundamental limitation for interferometric gravitational wave (GW) detectors. Here, we experimentally demonstrate for the first time a reduction in a mirror's thermal fluctuation in a GW detector with sapphire mirrors from the Cryogenic Laser Interferometer Observatory at 17\,K and 18\,K. The detector sensitivity, which was limited by the mirror's thermal fluctuation at room temperature, was improved in the frequency range of 90\,Hz to 240\,Hz by cooling the mirrors. The improved sensitivity reached a maximum of 2.2×1019m/Hz2.2 \times 10^{-19}\,\textrm{m}/\sqrt{\textrm{Hz}} at 165\,Hz.Comment: Accepted for publication in Physical Review Letters, 5 pages, 2 figure

    Conduction Effect of Thermal Radiation in a Metal Shield Pipe in a Cryostat for a Cryogenic Interferometric Gravitational Wave Detector

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    A large heat load caused by thermal radiation through a metal shield pipe was observed in a cooling test of a cryostat for a prototype of a cryogenic interferometric gravitational wave detector. The heat load was approximately 1000 times larger than the value calculated by the Stefan-Boltzmann law. We studied this phenomenon by simulation and experiment and found that it was caused by the conduction of thermal radiation in a metal shield pipe.Comment: 7 pages, 4 figures, 2 tables, Submitted to Jpn. J. Appl. Phy

    Pervasive Developmental Disorders and Autism Spectrum Disorders: Are These Disorders One and the Same?

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    The concept of pervasive developmental disorders (PDD) and autism spectrum disorders (ASD) closely resemble each other. Both ICD-10 and DSM-IV use the term PDD. The authors surveyed the perception of PDD/ASD and attitudes toward terminology. The subjects of this study were 205 medical/social-welfare professionals working in fields relating to developmental disorders. Questionnaires were mailed to site investigators at the collaborating institutes. With regard to what the scope of ASD and PDD encompasses, the answers were almost equally divided among three views: ASD and PDD are the same, PDD is wider in scope and ASD is wider. The terms PDD and autism were used in slightly different ways depended upon the situation. Our results demonstrate that the parameters of PDD and ASD are unclear and that the terms related to PDD/ASD are often used differently. Further studies are required to develop more clear and reliable diagnostic criteria for PDD

    Characteristics and in-hospital mortality of patients with COVID-19 from the first to fifth waves of the pandemic in 2020 and 2021 in the Japanese Medical Data Vision database

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    Objectives We aimed to describe patient characteristics, healthcare utilization, and in-hospital mortality among patients with COVID-19 in Japan across waves. Methods Using a large-scale hospital-based database, we identified patients hospitalized for COVID-19 in the first (January–June 2020), second (June–October 2020), third (October 2020–February 2021), fourth (March–June 2021), and fifth (June–December 2021) waves. We summarized patient characteristics, healthcare utilization, and in-hospital mortality during each wave and performed multivariable logistic regression analyses for in-hospital mortality. Results From the first to fifth waves, the number of patients (mean age ± standard deviation, years) was 2958 (61.2 ± 22.8), 7981 (55.6 ± 25.3), 18,788 (63.6 ± 22.9), 17,729 (60.6 ± 22.6), and 23,656 (51.2 ± 22.3), respectively. There were 190 (6.4%), 363 (4.5%), 1261 (6.7%), 1081 (6.1%), and 762 (3.2%) in-hospital deaths, respectively. The adjusted odds ratios for in-hospital deaths (95% confidence interval) were 0.78 (0.65–0.95), 0.94 (0.79–1.12), 0.99 (0.84–1.18), 0.77 (0.65–0.92), in the second to fifth waves, respectively, compared with the first wave. Conclusions In-hospital COVID-19 mortality improved from the first to the second wave; however, during the third and fourth waves, mortality was as serious as in the first wave. Although in-hospital mortality during the fifth wave improved, careful monitoring is needed for upcoming waves, considering changing patient and viral characteristics
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