414 research outputs found

    Radiation hydrodynamics simulations of wide-angle outflows from super-critical accretion disks around black holes

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    By performing two-dimensional radiation hydrodynamics simulations with large computational domain of 5000 Schwarzschild radius, we revealed that wide-angle outflow is launched via the radiation force from the super-critical accretion flows around black holes. The angular size of the outflow, of which the radial velocity (v_r) is over the escape velocity (v_esc), increases with an increase of the distance from the black hole. As a result, the mass is blown away with speed of v_r > v_esc in all direction except for the very vicinity of the equatorial plane, theta=0-85^circ, where theta is the polar angle. The mass ejected from the outer boundary per unit time by the outflow is larger than the mass accretion rate onto the black hole, ~150L_Edd/c^2, where L_Edd and c are the Eddington luminosity and the speed of light. Kinetic power of such wide-angle high-velocity outflow is comparable to the photon luminosity and is a few times larger than the Eddington luminosity. This corresponds to ~10^39-10^40 erg/s for the stellar mass black holes. Our model consistent with the observations of shock excited bubbles observed in some ultra-luminous X-ray sources (ULXs), supporting a hypothesis that ULXs are powered by the super-critical accretion onto stellar mass black holes.Comment: 9 pages, 8 figures, accepted for publication in PAS

    IoT measurements of the winter environment around Lake Izunuma, Miyagi

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    The Tenth Symposium on Polar Science/Ordinary sessions: [OM] Polar Meteorology and Glaciology, Wed. 4 Dec. / Entrance Hall (1st floor) , National Institute of Polar Researc

    Elderly patient with 5q spinal muscular atrophy type 4 markedly improved by Nusinersen

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    Available online 17 May 2020.ArticleJournal of the Neurological Sciences.415:116901(2020)journal articl

    Circadian rhythmic kinase CK2α phosphorylates BMAL1 to regulate the mammalian clock

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    Clock proteins govern circadian physiology and their function is regulated by a variety of signaling pathways. Here, we show that p45^PFK^, a previously reported circadian rhythmic kinase, corresponds to CK2[alpha]. Rhythmic phosphorylation of the core clock protein BMAL1 by CK2[alpha] occurs in the suprachiasmatic nuclei (SCN), the mammalian central pacemaker. Circadian BMAL1 phosphorylation controls its nucleocytoplasmic localization. Gene silencing for CK2[alpha] and BMAL1 mutagenesis of a highly conserved CK2 phosphorylation site (Ser 90) result in impaired BMAL1 accumulation in the nucleus and subsequent disruption of clock function. These findings reveal that circadian rhythmic kinase CK2 is an essential regulator of the mammalian circadian system

    Theory of optical transitions in graphene nanoribbons

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    Matrix elements of electron-light interactions for armchair and zigzag graphene nanoribbons are constructed analytically using a tight-binding model. The changes in wavenumber (Δn\Delta n) and pseudospin are the necessary elements if we are to understand the optical selection rule. It is shown that an incident light with a specific polarization and energy, induces an indirect transition (Δn=±1\Delta n=\pm1), which results in a characteristic peak in absorption spectra. Such a peak provides evidence that the electron standing wave is formed by multiple reflections at both edges of a ribbon. It is also suggested that the absorption of low-energy light is sensitive to the position of the Fermi energy, direction of light polarization, and irregularities in the edge. The effect of depolarization on the absorption peak is briefly discussed.Comment: 11 pages, 7 figure

    Promoter Polymorphism of RGS2 Gene Is Associated with Change of Blood Pressure in Subjects with Antihypertensive Treatment: The Azelnidipine and Temocapril in Hypertensive Patients with Type 2 Diabetes Study

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    We performed a prospective study to examine the genetic effect on the response to a calcium (Ca) channel blocker, azelnidipine and an ACE inhibitor, temocapril treatment in patients with hypertension, as a part of the prior clinical trial, the Azelnidipine and Temocapril in Hypertensive Patients with Type 2 Diabetes Study (ATTEST). Methods and Results. All subjects who gave informed consent for genetic research were divided into two groups: the subjects treated with azelnidipine or temocapril, for 52 weeks. We selected 18 susceptible genes for hypertension and determined their genotypes using TaqMan PCR method. RNA samples were extracted from peripheral blood, and quantitative real time PCR for all genes was performed using TaqMan method. One of the polymorphisms of the RGS2 gene was extracted as being able to influence the effect of these treatments to reduce BP. At eight weeks, BP change showed a significant interaction between the A-638G polymorphism of Regulator of G protein signaling-2 (RGS2) gene and treatment with azelnidipine or temocapril. There was no gene whose expression was associated with BP phenotypes or the polymorphisms of each gene. Conclusions. A-638G polymorphism of the RGS-2 gene could be a predictive factor for therapeutic performance of Ca channel blockers

    Photoprecursor approach as an effective means for preparing multilayer organic semiconducting thin films by solution processes

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    [プレスリリース]「重ね塗り」で有機薄膜太陽電池を高性能化~光を当てると固まる材料使い、有効性を実証~プラスチック上にも作製可能 (2014/11/19)The vertical composition profile of active layer has a major effect on the performance of organic photovoltaic devices (OPVs). While stepwise deposition of different materials is a conceptually straightforward method for controlled preparation of multi-component active layers, it is practically challenging for solution processes because of dissolution of the lower layer. Herein, we overcome this difficulty by employing the photoprecursor approach, in which a soluble photoprecursor is solution-deposited then photoconverted in situ to a poorly soluble organic semiconductor. This approach enables solution-processing of the p-i-n triple-layer architecture that has been suggested to be effective in obtaining efficient OPVs. We show that, when 2,6-dithienylanthracene and a fullerene derivative PC71BM are used as donor and acceptor, respectively, the best p-i-n OPV affords a higher photovoltaic efficiency than the corresponding p-n device by 24% and bulk-heterojunction device by 67%. The photoprecursor approach is also applied to preparation of three-component p-i-n films containing another donor 2,6-bis(59-(2-ethylhexyl)-(2,29-bithiophen)-5-yl)anthracene in the i-layer to provide a nearly doubled efficiency as compared to the original two-component p-i-n system. These results indicate that the present approach can serve as an effective means for controlled preparation of well-performing multi-component active layers in OPVs and relatedorganic electronic devices
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