137 research outputs found

    Reduced non-Gaussianity by 30s rapid update in convective-scale numerical weather prediction

    Get PDF
    Non-Gaussian forecast error is a challenge for ensemble-based data assimilation (DA), particularly for more nonlinear convective dynamics. In this study, we investigate the degree of the non-Gaussianity of forecast error distributions at 1km resolution using a 1000-member ensemble Kalman filter, and how it is affected by the DA update frequency and observation number. Regional numerical weather prediction experiments are performed with the SCALE (Scalable Computing for Advanced Library and Environment) model and the LETKF (local ensemble transform Kalman filter) assimilating phased array radar observations every 30s. The results show that non-Gaussianity develops rapidly within convective clouds and is sensitive to the DA frequency and the number of assimilated observations. The non-Gaussianity is reduced by up to 40% when the assimilation window is shortened from 5min to 30s, particularly for vertical velocity and radar reflectivity.Fil: Ruiz, Juan Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones del Mar y la Atmósfera. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones del Mar y la Atmósfera; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; Argentina. Instituto Franco-Argentino sobre Estudios del Clima y sus Impactos; Argentina. Rikagaku Kenkyujo; JapónFil: Lien, Guo-Yuan. Central Weather Bureau, Taiwan; ArgentinaFil: Kondo, Keiichi. Meteorological Research Institute; JapónFil: Otsuka, Shigenori. Rikagaku Kenkyujo; JapónFil: Miyoshi, Takemasa. Rikagaku Kenkyujo; Japón. University of Maryland; Estados Unidos. Japan Agency for Marine-Earth Science and Technology; Japó

    Comparison of two types of polar cap aurora: Simultaneous observations with ASI and ISR at Resolute Bay, Canada

    Get PDF
    第6回極域科学シンポジウム[OS] 宙空圏11月16日(月) 国立極地研究所1階交流アトリウ

    BP and Vascular Function Following Space Flight

    Get PDF
    Blood pressure and mesenteric resistance artery function were assessed in 9-week-old spontaneously hypertensive rats following an 18 day shuttle flight on STS-80. Blood pressure was measured twice, first in conscious animals using a tail-cuff method and then while the animals were anesthetized with 2% halothane in O2. Isolated mesenteric resistance artery responses to cumulative additions of norepinephrine, acetylcholine, sodium nitroprusside, and calcium were measured within 17 hours of landing using wire myography. Blood pressure was slightly reduced in conscious animals following flight (p=0.056) but was significantly elevated (p less than.001) above vivarium control group values in anesthetized animals. Maximal contraction of mesenteric arteries to norepinephrine was attenuated in the flight animals (p less than.001)aswasrelaxationtoacetylcholine(p less than .001)andcalcium(p less than .05). There was no difference between flight and control animals in the vessel response to sodium nitroprusside (p greater than .05). The results suggest that there may have been an increase in synthesis and release of nitric oxide in the flight animals

    Gallstones were associated with the gastrointestinal adverse events of cinacalcet in hemodialysis patients with secondary hyperparathyroidism

    No full text
    This study aimed to investigate the association of gastrointestinal (GI) adverse events of cinacalcet with gallstones in the hemodialysis (HD) patients with secondary hyperparathyroidism (SHPT). A total of 23 HD patients under the treatment with cinacalcet and 101 control patients were enrolled in this cross-sectional study. We investigated the prevalence of gallstones and the association of GI adverse events of cinacalcet with gallstones. The prevalence of gallstones was significantly higher in the HD patients with cinacalcet compared with the controls (47.8% vs. 15.8%). The longer time on HD, hypercalcemia, hyperphosphatemia and elevated parathyroid hormone level were observed in the HD patients with cinacalcet. Besides, GI adverse events of cinacalcet were observed more frequently in the HD patients with gallstones compared with those without gallstones (odds ratio 13.5, 95% CI: 1.80–101). Therefore, screening for gallstones before dosing cinacalcet may reduce the risk of GI adverse events in SHPT patients
    corecore