433 research outputs found

    Numerical Analysis of the Dynamic Interaction between Two Closely Spaced Vertical-Axis Wind Turbines

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    To investigate the optimum layouts of small vertical-axis wind turbines, a two-dimensional analysis of dynamic fluid body interaction is performed via computational fluid dynamics for a rotor pair in various configurations. The rotational speed of each turbine rotor (diameter: D = 50 mm) varies based on the equation of motion. First, the dependence of rotor performance on the gap distance (gap) between two rotors is investigated. For parallel layouts, counter-down (CD) layouts with blades moving downwind in the gap region yield a higher mean power than counter-up (CU) layouts with blades moving upwind in the gap region. CD layouts with gap/D = 0.5–1.0 yield a maximum average power that is 23% higher than that of an isolated single rotor. Assuming isotropic bidirectional wind speed, co-rotating (CO) layouts with the same rotational direction are superior to the combination of CD and CU layouts regardless of the gap distance. For tandem layouts, the inverse-rotation (IR) configuration shows an earlier wake recovery than the CO configuration. For 16-wind-direction layouts, both the IR and CO configurations indicate similar power distribution at gap/D = 2.0. For the first time, this study demonstrates the phase synchronization of two rotors via numerical simulatio

    Performance of new Kuraray wavelength-shifting fibers with short decay time

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    We measure the decay time and the attenuation length of newly developed wavelength-shifting fibers, YS series from Kuraray, which have fast response. Using a 405 nm laser, the decay times of the YS-2, 4, and 6 are measured to be 3.70±0.043.70 \pm 0.04 ns, 2.06±0.032.06 \pm 0.03 ns, and 1.50±0.021.50 \pm 0.02 ns, respectively. The decay time of Y-11 is measured to be 7.16±0.097.16 \pm 0.09 ns using the same system. All fibers are found to have similar attenuation lengths of more than 4 meters. When combined with the plastic scintillators EJ-200 and EJ-204, the YS series have better time resolution than Y-11, with light yields of 60-100% of Y-11.Comment: 10 pages, 8 figure

    Tumorigenesis of Epstein–Barr Virus-Positive Epithelial Cell Lines Derived from Gastric Tissues in the SCID Mouse

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    AbstractTo study the tumorigenesis of Epstein–Barr virus (EBV)-positive epithelial cell lines GT38 and GT39 derived from human gastric tissues, we inoculated these cells under the skin of severe combined immunodeficient (SCID) mice. The development of tumors was observed in each of the mice about 2 months after the inoculation. The tumors were diagnosed with undifferentiated carcinoma by hematoxylin/eosin staining. EBV-encoded small RNA1 was detected in the paraffin-embedded tumor sections. The tumor cells had human chromosome. The circular, but not linear, EBV DNA was detected in the tumors. The molecular sizes of EBV DNA termini were the same as that of the inoculated GT38 or GT39 cells. The expressions of EBV nuclear antigen 2 and latent membrane protein 1 reduced in the tumors. Transcripts of BamHI C and W promoters in latency III were detected in the tumors and the cultured cells in vitro. The tumor cells were passaged from one SCID mouse to other SCID mice and to cultures in vitro. This is the first evidence that the EBV-positive epithelial cell lines produced tumors in the SCID mouse

    Social communication impairments and restricted, repetitive patterns ("Kodawari") considered from the "Comprehension" section of the WISC-IV in autism spectrum disorder

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    Background: Many studies have used the Wechsler Intelligence Scale (WISC) to examine the characteristics of autism spectrum disorder (ASD). However, most studies have been based on profile analysis, not on content analysis. Objective: The objective of the present study was to apply the WISC-IV to clinical assessment of ASD and clarify how the characteristics of the disorder were reflected in specific items. Methods: The study participants were 20 patients aged 5-16 years diagnosed with ASD according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5). We recruited 20 patients with attention-deficit/hyperactivity disorder (ADHD) and 20 patients with other disorders (neurotic disorders) as controls. We then compared the scores of the ninth item of the WISC-IV ("Comprehension") among the three groups. Results: The differences observed between the ASD vs. the other disorders group were not significant by the standard scoring method. Thus, a two-level scoring method of 0 and ≥1 point was adopted. As a result, significantly more participants in the ASD group scored 0 points compared with the ADHD and other disorders grou

    Effects of gaps in priorities between ideal and real lives on psychological burnout among academic faculty members at a medical university in Japan: a cross-sectional study

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    Background: Accumulating evidence from medical workforce research indicates that poor work/life balance and increased work/home conflict induce psychological distress. In this study we aim to examine the existence of a priority gap between ideal and real lives, and its association with psychological burnout among academic professionals. Methods: This cross-sectional survey, conducted in 2014, included faculty members (228 men, 102 women) at a single medical university in Tokyo, Japan. The outcome of interest was psychological burnout, measured with a validated inventory. Discordance between ideal-and real-life priorities, based on participants' responses (work, family, individual life, combinations thereof), was defined as a priority gap. Results: The majority (64%) of participants chose "work" as the greatest priority in real life, but only 28% chose "work" as the greatest priority in their conception of an ideal life. Priority gaps were identified in 59.5% of respondents. A stepwise multivariable general linear model demonstrated that burnout scores were associated positively with respondents' current position (P < 0.0018) and the presence of a priority gap (P < 0.0001), and negatively with the presence of social support (P < 0.0001). Among participants reporting priority gaps, burnout scores were significantly lower in those with children than in those with no children (P-interaction = 0.011); no such trend was observed in participants with no priority gap. Conclusions: A gap in priorities between an ideal and real life was associated with an increased risk of burnout, and the presence of children, which is a type of "family" social support, had a mitigating effect on burnout among those reporting priority gaps

    Multiple Physical Symptoms Are Useful to Identify High Risk Individuals for Burnout: A Study on Faculties and Hospital Workers in Japan

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    Healthcare workers have a high risk of burnout. This study aimed to investigate if the numbers of physical symptoms are associated with burnout among healthcare workers. We conducted a cross-sectional survey at a large university in Tokyo, Japan, in 2016. Participants were 1080: 525 faculties and 555 hospital workers. We investigated 16 physical symptoms perceived more than once per week and examined the association between the number of physical symptoms and Copenhagen Burnout Inventory (CBI); work-related (WBO), personal (PBO), and client-related (CBO) burnout. All CBI scores were higher among hospital workers than among faculties: WBO (43 vs. 29), PBO (50 vs. 33), CBO (33 vs. 29). Moreover, the higher the number of physical symptoms perceived, the higher the degree of burnout scores became (trend p-values < 0.001), except for CBO among faculties. Job strain (all except for CBO among hospital workers) and work-family conflict were associated with an increased risk of burnout. Being married (WBO and CBO among faculties), having a child (except for PBO and CBO among faculties), and job support (faculty and hospital workers with WBO and faculties with PBO) were associated with a decreased risk of burnout. Multiple physical symptoms might be useful for identifying high risk individuals for burnout
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