54 research outputs found

    Wheeze is an unreliable endpoint for bronchial methacholine challenges in preschool children

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    Background: Onset of wheeze is the endpoint often used in the determination of a positive bronchial challenge test (BCT) in young children who cannot perform spirometry. We sought to assess several clinical endpoints at the time of a positive BCT in young children with recurrent wheeze compared to findings in school-aged children with asthma. Methods: Positive BCT was defined in: (1) preschool children (n = 22) as either persistent cough, wheeze, fall in oxygen saturation (SpO2 ) of ≥5%, or ≥50% increase in respiratory rate (RR) from baseline; and (2) school-aged children (n = 22) as the concentration of methacholine (MCh) required to elicit a 20% decline in FEV1 (PC20 ). Results: All preschool children (mean age 3.4 years) had a positive BCT (median provocative MCh concentration 1.25 mg/ml [IQR, 0.62, 1.25]). Twenty (91%) school-aged children (mean age 11.3 years) had a positive BCT (median PC20 1.25 mg/ml [IQR, 0.55, 2.5]). At the time of the positive BCT, the mean fall in SpO2 (6.9% vs. 3.8%; p = .001) and the mean % increase in RR (61% vs. 22%; p < .001) were greater among preschool-aged than among school-aged children. A minority of children developed wheeze at time of positive BCT (23% preschool- vs. 15% school-aged children; p = .5). Conclusions: The use of wheeze as an endpoint for BCT in preschool children is unreliable, as it rarely occurs. The use of clinical endpoints, such as ≥25% increase in RR or fall in SpO2 of ≥3%, captured all of our positive BCT in preschool children, while minimizing undue respiratory distress

    The ASTRO-H X-ray Observatory

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    The joint JAXA/NASA ASTRO-H mission is the sixth in a series of highly successful X-ray missions initiated by the Institute of Space and Astronautical Science (ISAS). ASTRO-H will investigate the physics of the high-energy universe via a suite of four instruments, covering a very wide energy range, from 0.3 keV to 600 keV. These instruments include a high-resolution, high-throughput spectrometer sensitive over 0.3-2 keV with high spectral resolution of Delta E < 7 eV, enabled by a micro-calorimeter array located in the focal plane of thin-foil X-ray optics; hard X-ray imaging spectrometers covering 5-80 keV, located in the focal plane of multilayer-coated, focusing hard X-ray mirrors; a wide-field imaging spectrometer sensitive over 0.4-12 keV, with an X-ray CCD camera in the focal plane of a soft X-ray telescope; and a non-focusing Compton-camera type soft gamma-ray detector, sensitive in the 40-600 keV band. The simultaneous broad bandpass, coupled with high spectral resolution, will enable the pursuit of a wide variety of important science themes.Comment: 22 pages, 17 figures, Proceedings of the SPIE Astronomical Instrumentation "Space Telescopes and Instrumentation 2012: Ultraviolet to Gamma Ray

    The Quiescent Intracluster Medium in the Core of the Perseus Cluster

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    Clusters of galaxies are the most massive gravitationally-bound objects in the Universe and are still forming. They are thus important probes of cosmological parameters and a host of astrophysical processes. Knowledge of the dynamics of the pervasive hot gas, which dominates in mass over stars in a cluster, is a crucial missing ingredient. It can enable new insights into mechanical energy injection by the central supermassive black hole and the use of hydrostatic equilibrium for the determination of cluster masses. X-rays from the core of the Perseus cluster are emitted by the 50 million K diffuse hot plasma filling its gravitational potential well. The Active Galactic Nucleus of the central galaxy NGC1275 is pumping jetted energy into the surrounding intracluster medium, creating buoyant bubbles filled with relativistic plasma. These likely induce motions in the intracluster medium and heat the inner gas preventing runaway radiative cooling; a process known as Active Galactic Nucleus Feedback. Here we report on Hitomi X-ray observations of the Perseus cluster core, which reveal a remarkably quiescent atmosphere where the gas has a line-of-sight velocity dispersion of 164+/-10 km/s in a region 30-60 kpc from the central nucleus. A gradient in the line-of-sight velocity of 150+/-70 km/s is found across the 60 kpc image of the cluster core. Turbulent pressure support in the gas is 4% or less of the thermodynamic pressure, with large scale shear at most doubling that estimate. We infer that total cluster masses determined from hydrostatic equilibrium in the central regions need little correction for turbulent pressure.Comment: 31 pages, 11 Figs, published in Nature July

    Hitomi (ASTRO-H) X-ray Astronomy Satellite

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    The Hitomi (ASTRO-H) mission is the sixth Japanese x-ray astronomy satellite developed by a large international collaboration, including Japan, USA, Canada, and Europe. The mission aimed to provide the highest energy resolution ever achieved at E  >  2  keV, using a microcalorimeter instrument, and to cover a wide energy range spanning four decades in energy from soft x-rays to gamma rays. After a successful launch on February 17, 2016, the spacecraft lost its function on March 26, 2016, but the commissioning phase for about a month provided valuable information on the onboard instruments and the spacecraft system, including astrophysical results obtained from first light observations. The paper describes the Hitomi (ASTRO-H) mission, its capabilities, the initial operation, and the instruments/spacecraft performances confirmed during the commissioning operations for about a month

    Finishing the euchromatic sequence of the human genome

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    The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

    A cross-sectional survey on the status of oral health administration for students in Japanese universities

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    Purpose: A rapid deterioration of oral health after high school age is an issue to be addressed in Japan. Although this problem may relate to the weakness of oral health promotion for university students, the investigation of oral health-promoting activities, including annual dental checkups (DCs), undertaken by universities has never been conducted. Therefore, a questionnaire survey among health administration departments (HADs) was conducted to clarify the status of oral health-promoting activities for students. Methods: Self-administered questionnaire was voluntarily answered by HAD’s staff in 2015-2016. The major questions were on information concerning the university, HAD’s staff, implementation of DCs, and oral health-promoting activities for students. Results: Of 295 universities, 130 valid responses (response rate 44.1%) were analyzed. DCs were implemented in 10.9% of the universities. The main reasons for not implementing DCs were the large budgetary burden and low needs of students. The dental clinic introductory service was undertaken by 62.3%, whereas provision of oral health information was undertaken by only 23.8%. Conclusion: A low ratio of universities implemented DCs and provided oral health information. Further expansion of DC implementation is considered difficult because of the budgetary burden. Promoting the provision of oral health information from universities is required to improve students’ oral health
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