68 research outputs found

    A phantom study investigating the relationship between ground-glass opacity visibility and physical detectability index in low-dose chest computed tomography

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    In this study, the relationship between ground-glass opacity (GGO) visibility and physical detectability index in low-dose computed tomography (LDCT) for lung cancer screening was investigated. An anthropomorphic chest phantom that included synthetic GGOs with CT numbers of -630 Hounsfield units (HU; high attenuation GGO: HGGO) and -800 HU (low attenuation GGO: LGGO), and three phantoms for physical measurements were employed. The phantoms were scanned using 12 CT systems located in 11 screening centers in Japan. The slice thicknesses and CT dose indices (CTDIvol) varied over 1.0-5.0 mm and 0.85-3.30 mGy, respectively, and several reconstruction kernels were used. Physical detectability index values were calculated from measurements of resolution, noise, and slice thickness properties for all image sets. Five radiologists and one thoracic surgeon, blind to one another\u27s observations, evaluated GGO visibility using a five-point scoring system. The physical detectability index correlated reasonably well with the GGO visibility (R2 = 0.709, p vol. Consequently, the CTDIvol also correlated reasonably well with the GGO visibility (R2 = 0.701, p vol was nearly dominant in the GGO visibility for image sets with different reconstruction kernels and slice thicknesses, used in this study

    Introduction to Digital Fujikawa –History of Medicine in Japan–

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    [The 2019 International Image Interoperability Framework (IIIF) Conference] 2019/06/24-28, Göttingen, GermanyThe Fujikawa collection is a collection of old medical books that had been collected by Dr. Yu Fujikawa (1865-1940). Books in the collection are stored in multiple institutions including Kyoto University, Keio University, and the University of Tokyo. This presentation describes our project “Digital Fujikawa –History of Medicine in Japan–”, which has been jointly launched by Kyoto University Library Network and Keio University Media Center. The project intends to contribute to the development of the research in the history of medicine in Japan by providing the comprehensive view of the Fujikawa Collection that has been physically distributed over different institutions. On September 28, 2018, we launched a website (http://www.kulib.kyoto-u.ac.jp/rdl/digital_fujikawa/en/) that virtually brings together the holdings of different institutions in one place using IIIF protocols. As of February 22, 2019, the website delivers 5, 333 titles from three institutions. In the presentation, we look back on different implementations that we examined during the development of the website. In addition, we report the influence of the project on usage statistics of titles. In the future, we increase digital images available and participating institutions and develop new functions, in order to progress this project from the current trial phase to a full-scale phase by the end of academic year 2020/2021. Acknowledgements: the digitization of the Fujikawa collections has been supported by the following projects: (1) Project to build an international collaborative research network for pre-modern Japanese texts (NIJL-NW project) by the National Institute of Japanese Literature, (2) Grants for functional enhancements by the Ministry of Education, Culture, Sports, Science and Technology, (3) Kyoto University Open Access Promotion Project, and (4) Keio University Media Center (ordinary expenses)

    Treatment responses and their predictors in patients with rheumatoid arthritis treated with biological agents

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    Biological agents represent an important advancement in for the treatment of rheumatoid arthritis (RA), but there is a subset of patients who do not improve despite therapy. This study aimed to determine the efficacy of biological agents for RA and to identify clinical factors that are associated with their response. We studied 98 patients with RA who started an initiating biological agent which was selected from infliximab, etanercept, adalimumab and tociliximab at 4 medical institutions. Etanercept was the most frequently used biological agent followed by infliximab although there was a difference in the selection of the biological agents among medical institutions. We found that etanercept achieved the highest treatment response, remission rate and drug survival rate. A high disease activity in the baseline disease activity score-c-reactive protein (CRP) was shown to be a negative predictor of the treatment response, and high patient global assessment was significantly less likely to achieve a good response. At week 4, decreases in 28 swollen joint counts and CRP were useful as predictors for sustaining the efficacy up to week 48. These data demonstrate that assessments of the disease activity at baseline and the early treatment response may be useful in predicting the efficacy and drug survival rate of biological agents

    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

    Giant Magnons on CP^3 by Dressing Method

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    We consider classical string spectrum of R x CP^3, and construct a family of solutions with residual SU(2) symmetry by the dressing method on SU(4)/U(3) sigma model. All of them obey the square-root type dispersion relation, as is expected from the su(2|2) symmetry. A single dyonic giant magnon is not found in this approach.Comment: 1+29 pages, 1 figure, v2: a figure and references added, minor corrections, v3: remarks on semiclassical quantization added. To be published in JHE

    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
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