200 research outputs found

    X-ray spectral diagnostics for satellite lines of H-like Mg ions measured by a high resolution spectrometer

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    X-ray spectra of H-like Mg ions produced in a laser plasma have been measured by space-resolved high-resolution spectroscopy. We identified satellite lines near Ly[alpha] lines, 2lnl′ ? 1snl′ + h[nu] for n = 2, 3, and 4. We construct a collisional radiative model including the doubly excited states for the intensity ratios of satellite lines. We use atomic data calculated by different methods for satellite lines and compare the results. We derive the electron temperature and density of the laser-produced plasma by a new technique using intensity ratios of only satellite lines. This technique is useful because the Ly[alpha] lines are often affected by opacity

    X-ray Astronomy in the Laboratory with a Miniature Compact Object Produced by Laser-Driven Implosion

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    Laboratory spectroscopy of non-thermal equilibrium plasmas photoionized by intense radiation is a key to understanding compact objects, such as black holes, based on astronomical observations. This paper describes an experiment to study photoionizing plasmas in laboratory under well-defined and genuine conditions. Photoionized plasma is here generated using a 0.5-keV Planckian x-ray source created by means of a laser-driven implosion. The measured x-ray spectrum from the photoionized silicon plasma resembles those observed from the binary stars Cygnus X-3 and Vela X-1 with the Chandra x-ray satellite. This demonstrates that an extreme radiation field was produced in the laboratory, however, the theoretical interpretation of the laboratory spectrum significantly contradicts the generally accepted explanations in x-ray astronomy. This model experiment offers a novel test bed for validation and verification of computational codes used in x-ray astronomy.Comment: 5 pages, 4 figures are included. This is the original submitted version of the manuscript to be published in Nature Physic

    Characterization of histopathology and gene-expression profiles of synovitis in early rheumatoid arthritis using targeted biopsy specimens

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    The disease category of early rheumatoid arthritis (RA) has been limited with respect to clinical criteria. Pathological manifestations of synovitis in patients whose disease is clinically classified as early RA seem to be heterogeneous, with regular variations. To clarify the relation between the molecular and histopathological features of the synovitis, we analyzed gene-expression profiles in the synovial lining tissues to correlate them with histopathological features. Synovial tissues were obtained from knee joints of 12 patients with early RA by targeted biopsy under arthroscopy. Surgical specimens of long-standing RA (from four patients) were examined as positive controls. Each histopathological parameter characteristic of rheumatoid synovitis in synovial tissues was scored under light microscopy. Total RNAs from synovial lining tissues were obtained from the specimens selected by laser capture microdissection and the mRNAs were amplified by bacteriophage T7 RNA polymerase. Their cDNAs were analyzed in a cDNA microarray with 23,040 cDNAs, and the levels of gene expression in multilayered lining tissues, compared with those of normal-like lining tissues in specimens from the same person, were determined to estimate gene-expression profiles characteristic of the synovial proliferative lesions in each case. Based on cluster analysis of all cases, gene-expression profiles in the lesions in early RA fell into two groups. The groups had different expression levels of genes critical for proliferative inflammation, including those encoding cytokines, adhesion molecules, and extracellular matrices. One group resembled synovitis in long-standing RA and had high scores for some histopathological features – involving accumulations of lymphocytes and plasma cells – but not for other features. Possible differences in the histopathogenesis and prognosis of synovitis between the two groups are discussed in relation to the candidate genes and histopathology

    Benzene substituted with bipyridine and terpyridine as electron-transporting materials for organic light-emitting devices

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    New electron-transporting materials for organic light-emitting devices (OLEDs) based on trisubstituted benzene with both bipyridine and terpyridine, 1,3-bisbipyridyl-5-terpyridylbenzene (BBTB) and 1-bipyridyl-3,5-bisterpyridylbenzene (BTBB), were developed. Glass transition temperatures of BBTB and BTBB were 93 degrees C and 108 degrees C, respectively, and BTBB was completely amorphous with no melting point. Electron mobilities of BTBB exceeded the order of 10(-4) cm(2) V-1 s(-1), while those of BBTB were very high and reached 10(-3) cm(2) V-1 s(-1) at an electric field of approximately 500 kV cm(-2). These high mobilities contributed to a low voltage operation. For example, in the case of the conventional aluminum trisquinolinol (Alq)-based fluorescent OLED with BTBB, current densities of 3.5 mA cm(-2) and 100 mA cm(-2) were reached at voltages of 3.0 V and 4.5 V, respectively. In addition, ionization potentials of BBTB (6.33 eV) and BTBB (6.50 eV) were sufficiently large to confine holes in common emissive layers.ArticleJOURNAL OF MATERIALS CHEMISTRY. 22(14):6765-6773 (2012)journal articl

    Effectiveness of outpatient-based group cognitive-behavioral therapy in Japanese patients with mood disorders and neurotic disorders

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    Background: Although the effectiveness of group cognitive-behavioral therapy (GCBT) has been studied, evidence is still not sufficient. Objective: The aim of the present study is to consider the effectiveness of GCBT with mood disorders and neurotic disorders. Methods: The present study assessed a total of 32 patients who were classified as F3 (mood disorders) or F4 (neurotic disorders) according to the ICD-10, and who attended GCBT sessions offered at The Tokai University Hospital. Depression and mood in these patients were assessed before and after GCBT by using the Center for Epidemiologic Studies Depression Scale (CES-D) and the Profile of Mood States (POMS). Results: A comparison of pre- and post-GCBT CES-D scores among all patients as well as within F3 and F4 groups showed a significant decrease in CES-D scores after GCBT. As for the POMS, a comparison of pre- and post-GCBT scores among all patients showed a significant improvement in “vigor” and “confusion” scores after GCBT. Discussion: The present study demonstrated that GCBT can relieve depression and improve some mood states. Furthermore, the GCBT sessions offered proved to be effective even when administered to a group of participants consisting of both mood disorders and neurotic disorder patients

    Benzene substituted with bipyridine and terpyridine as electron-transporting materials for organic light-emitting devices

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    New electron-transporting materials for organic light-emitting devices (OLEDs) based on trisubstituted benzene with both bipyridine and terpyridine, 1,3-bisbipyridyl-5-terpyridylbenzene (BBTB) and 1-bipyridyl-3,5-bisterpyridylbenzene (BTBB), were developed. Glass transition temperatures of BBTB and BTBB were 93 degrees C and 108 degrees C, respectively, and BTBB was completely amorphous with no melting point. Electron mobilities of BTBB exceeded the order of 10(-4) cm(2) V-1 s(-1), while those of BBTB were very high and reached 10(-3) cm(2) V-1 s(-1) at an electric field of approximately 500 kV cm(-2). These high mobilities contributed to a low voltage operation. For example, in the case of the conventional aluminum trisquinolinol (Alq)-based fluorescent OLED with BTBB, current densities of 3.5 mA cm(-2) and 100 mA cm(-2) were reached at voltages of 3.0 V and 4.5 V, respectively. In addition, ionization potentials of BBTB (6.33 eV) and BTBB (6.50 eV) were sufficiently large to confine holes in common emissive layers.ArticleJOURNAL OF MATERIALS CHEMISTRY. 22(14):6765-6773 (2012)journal articl

    Sm系及びCe系充填スクッテルダイト化合物の熱電特性

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    Filled skutterudites have been actively studied as potentially useful thermoelectric materials. SmT4P12 (T=Fe, Ru, Os) and LaxCel-xT4P12(T=Ru, Os) (0 ≤ x ≤ O.2) with the filled skutterudite-type structure have been prepared at high temperature and high pressure. The structure of samples was characterized by powder X-ray diffraction. The thermoelectric properties of these compounds have been investigated by means of electrical resistivity, Seebeck coefficient and thermal conductivity measurements. SmFe4P12 and SmOs4P12 behaved metallic down to 5K, while SmRu4P12 shows metal-insulation transition around 16K. SmFe4P12 showed significantly high values of Seebeck coefficient (46μV/K), comparing to other metallic compounds at the temperature 600K. LaxCel-xT4P12 (T=Ru, Os) (0 ≤ x ≤ 0.2) showed semiconducting behavior, and the power factor was optimized by doping 10% La in CeRu4P12.投稿論

    Analysis of Fe XXI Spectral Lines Measured in LHD Plasma

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    We measured extreme ultraviolet spectra of plasmas in the Large Helical Device after an Fe pellet was injected and analyzed the Fe XXI spectral lines λ 12.12 nm (2s22p2 3P2-2s2p3 3P2) and λ 12.875 nm (2s22p2 3P0-2s2p3 3D1). By constructing a collisional-radiative model for Fe XXI, we obtained the electron density dependence of the line intensity ratio, which is the result of the excitation process among the fine-structure levels of the ground state, 2s22p2 3PJ by electron and proton impact. Using the obtained electron density dependence, we estimated the electron density from the measured intensity ratio. By comparing the estimated density with the electron density distribution measured by a far infrared interferometer, we could estimate the location of the Fe XXI emitting region. We found that Fe XXI appeared first around the density peak formed by the pellet and later expanded toward a low-density region. The corresponding electron temperature of the location is lower than that for ionization equilibrium, and the Fe XXI ions are expected to be in a non-equilibrium ionization state
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