7,015 research outputs found

    Misclassified type 1 AGNs in the local universe

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    We search for misclassified type 1 AGNs among type 2 AGNs identified with emission line flux ratios, and investigate the properties of the sample. Using 4\,113 local type 2 AGNs at 0.02<z<0.050.02<z<0.05 selected from Sloan Digital Sky Survey Data Release 7, we detected a broad component of the \Ha\ line with a Full-Width at Half-Maximum (FWHM) ranging from 1\,700 to 19\,090 \kms\ for 142 objects, based on the spectral decomposition and visual inspection. The fraction of the misclassified type 1 AGNs among type 2 AGN sample is \sim3.5%, implying that a large number of missing type 1 AGN population may exist. The misclassified type 1 AGNs have relatively low luminosity with a mean broad \Ha\ luminosity, log LHα=40.50±0.35_{H\alpha} = 40.50\pm0.35 \ergs, while black hole mass of the sample is comparable to that of the local black hole population, with a mean black hole mass, log MBH=6.94±0.51_{\rm BH} = 6.94\pm0.51 M_{\odot}. The mean Eddington ratio of the sample is log Lbol_{\rm bol}/LEdd_{\rm Edd} = 2.00±0.40-2.00\pm0.40, indicating that black hole activity is relatively weak, hence, AGN continuum is too weak to change the host galaxy color. We find that the \OIII\ lines show significant velocity offsets, presumably due to outflows in the narrow-line region, while the velocity offset of the narrow component of the \Ha\ line is not prominent, consistent with the ionized gas kinematics of general type 1 AGN population.Comment: 12 pages, 8 figures, JKAS in pres

    Sharp low energy feature in single-particle spectra due to forward scattering in dd-wave cuprate superconductors

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    There is an enormous interest in renormalization of quasi-particle (qp) dispersion relation of cuprate superconductors both below and above the critical temperature TcT_c because it enables determination of the fluctuation spectrum to which the qps are coupled. A remarkable discovery by angle-resolved photoemission spectroscopy (ARPES) is a sharp low energy feature (LEF) in qp spectra well below the superconducting energy gap but with its energy increasing in proportion to TcT_c and its intensity increasing sharply below TcT_c. This unexpected feature needs to be reconciled with dd-wave superconductivity. Here, we present a quantitative analysis of ARPES data from Bi2_2Sr2_2CaCu2_2O8+δ_{8+\delta} (Bi2212) using Eliashberg equations to show that the qp scattering rate due to the forward scattering impurities far from the Cu-O planes is modified by the energy gap below TcT_c and shows up as the LEF. This is also a necessary step to analyze ARPES data to reveal the spectrum of fluctuations promoting superconductivity.Comment: 11 pages, 7 figure, 1 table, Accepted for publication in Phys Rev Lett, Includes the Supplemental Materia

    Geophysical features of permafrost in the Canadian Beaufort Sea

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    第6回極域科学シンポジウム分野横断セッション:[IA] 急変する北極気候システム及びその全球的な影響の総合的解明―GRENE北極気候変動研究事業研究成果報告2015―11月19日(木) 国立極地研究所1階交流アトリウ

    Bare-metal stents versus drug-eluting stents in large (≥3.5mm) single coronary artery: Angiographic and clinical outcomes at 6 months

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    SummaryBackgroundAlthough drug-eluting stents (DES) have been shown to dramatically reduce restenosis and improve the rate of event-free survival in large randomized trials, the benefit of DES appears to be limited to restenosis. In large arteries, it is not clear which type of stent is more superior in angiographic and clinical outcomes between DES and bare-metal stents (BMS). We compared the angiographic and clinical outcomes of DES versus BMS in large arteries (≥3.5mm).MethodTwo hundred and forty patients from March 2002 to March 2007 received stents; 196 patients were treated with DES (44.9% sirolimus-eluting stents; 43.9% paclitaxel-eluting stents; 11.2% zotarolimus-eluting stents) and 44 with cobalt–chromium BMS for single de novo lesions in a large vessel. All subjects received aspirin, clopidogrel, and/or cilostazol as the standard antiplatelet regimen. The angiographic and clinical outcomes were evaluated at 6 months.ResultsFor the baseline characteristics, there were no significant differences between the DES and BMS groups. In addition, for the initially implanted stent there was no difference in the length, stent diameter, and lesion site between the two groups. After 6 months, the follow-up angiogram showed that in-stent diameter restenosis and late loss was more common with BMS than DES (39±21% vs. 19±17%, p=0.007; 1.44±0.83mm vs. 0.62±0.58mm, p=0.009, respectively). However, the target-lesion revascularization/target-vessel revascularization, and total major adverse cardiac events showed no significant differences between the groups (5.3% vs. 3.6%, p=0.62; 5.3% vs. 4.6%, p=0.86, respectively).ConclusionThe DES and cobalt–chromium BMS placed in large coronary arteries showed equally favorable 6-month clinical outcomes, although the 6-month angiographic results appeared more favorable in the DES group than in the BMS group

    Production of Transgenic Cloned Miniature Pigs with Membrane-bound Human Fas Ligand (FasL) by Somatic Cell Nuclear Transfer

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    Cell-mediated xenograft rejection, including NK cells and CD8+ CTL, is a major obstacle in successful pig-to-human xenotransplantation. Human CD8+ CTL and NK cells display high cytotoxicity for pig cells, mediated at least in part by the Fas/FasL pathway. To prevent cell-mediated xenocytotoxicity, a membrane-bound form of human FasL (mFasL) was generated as an inhibitor for CTL and NK cell cytotoxicity that could not be cleaved by metalloproteinase to produce putative soluble FasL. We produced two healthy transgenic pigs harboring the mFasL gene via somatic cell nuclear transfer (SCNT). In a cytotoxicity assay using transgenic clonal cell lines and transgenic pig ear cells, the rate of CD8+ CTL-mediated cytotoxicity was significantly reduced in transgenic pig&#x27;s ear cells compared with that in normal minipig fetal fibroblasts. Our data indicate that grafts of transgenic pigs expressing membrane-bound human FasL control the cellular immune response to xenografts, creating a window of opportunity to facilitate xenograft survival

    A sulfated polysaccharide of Ecklonia cava inhibits the growth of colon cancer cells by inducing apoptosis

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    We investigated anticancer effects of the crude polysaccharides (CPs) isolated from Ecklonia cava enzymatic extracts using AMG, Viscozyme, Protamex, and Alcalase enzyme against a colon cancer cell line, CT26 cells. Among them, the CP of Protamex extract (PCP) contained the highest fucose and sulfated group contents and showed the highest growth inhibitory effect against CT-26 cells. In addition, PCP dose-dependently increased the formation of apoptotic body and the percentage of Sub-G1 DNA contents. Also, PCP activated caspase 9 and PARP as regulating the expressions of Bax and Bcl-2. Moreover, PPP2, a fraction purified from PCP showed the highest growth inhibitory effect against CT 26 cells with the increased fucose and sulfated group contents. The results demonstrate that the isolated SP containing plentiful fucose and sulfated group contents has the anticancer effect on colon cancer cells via regulation of Bcl-2/Bax signal pathway

    Experimental observation of hidden Berry curvature in inversion-symmetric bulk 2H-WSe2

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    We investigate the hidden Berry curvature in bulk 2H-WSe2 by utilizing the surface sensitivity of angle resolved photoemission (ARPES). The symmetry in the electronic structure of transition metal dichalcogenides is used to uniquely determine the local orbital angular momentum (OAM) contribution to the circular dichroism (CD) in ARPES. The extracted CD signals for the K and K' valleys are almost identical but their signs, which should be determined by the valley index, are opposite. In addition, the sign is found to be the same for the two spin-split bands, indicating that it is independent of spin state. These observed CD behaviors are what are expected from Berry curvature of a monolayer of WSe2. In order to see if CD-ARPES is indeed representative of hidden Berry curvature within a layer, we use tight binding analysis as well as density functional calculation to calculate the Berry curvature and local OAM of a monolayer WSe2. We find that measured CD-ARPES is approximately proportional to the calculated Berry curvature as well as local OAM, further supporting our interpretation.Comment: 6 pages, 3 figure
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