1,736,148 research outputs found
Detailed optical and near-infrared polarimetry, spectroscopy and broad-band photometry of the afterglow of GRB 091018 : polarization evolution
Get PDFFollow-up observations of large numbers of gamma-ray burst (GRB) afterglows, facilitated by the Swift satellite, have produced a large sample of spectral energy distributions and light curves, from which their basic micro- and macro-physical parameters can in principle be derived. However, a number of phenomena have been observed that defy explanation by simple versions of the standard fireball model, leading to a variety of new models. Polarimetry can be a major independent diagnostic of afterglow physics, probing the magnetic field properties and internal structure of the GRB jets. In this paper we present the first high-quality multi-night polarimetric light curve of a Swift GRB afterglow, aimed at providing a well-calibrated data set of a typical afterglow to serve as a benchmark system for modelling afterglow polarization behaviour. In particular, our data set of the afterglow of GRB 091018 (at redshift z = 0.971) comprises optical linear polarimetry (R band, 0.13-2.3d after burst); circular polarimetry (R band) and near-infrared linear polarimetry (Ks band). We add to that high-quality optical and near-infrared broad-band light curves and spectral energy distributions as well as afterglow spectroscopy. The linear polarization varies between 0 and 3per cent, with both long and short time-scale variability visible. We find an achromatic break in the afterglow light curve, which corresponds to features in the polarimetric curve. We find that the data can be reproduced by jet break models only if an additional polarized component of unknown nature is present in the polarimetric curve. We probe the ordered magnetic field component in the afterglow through our deep circular polarimetry, finding P circ < 0.15per cent (2σ), the deepest limit yet for a GRB afterglow, suggesting ordered fields are weak, if at all present. Our simultaneous R- and Ks-band polarimetry shows that dust-induced polarization in the host galaxy is likely negligible
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Decreto No. 1197 de 1951
No full textSe publica el texto del decreto N° 1197 de 1951. Artículo publicado también en el Vol. 2 N°8 (1952)
EC67-1197 Shopping for a Refrigerator
Get PDFExtension Circular 67-1197: Shopping for a refrigerator: features for a good refrigerator
149. Juntoku tennō (1197-1242)
No full textIwao Seiichi, Iyanaga Teizō, Ishii Susumu, Yoshida Shōichirō, Fujimura Jun'ichirō, Fujimura Michio, Yoshikawa Itsuji, Akiyama Terukazu, Iyanaga Shōkichi, Matsubara Hideichi. 149. Juntoku tennō (1197-1242). In: Dictionnaire historique du Japon, volume 10, 1984. Lettre J. p. 79
Effects of MCL1 knockdown on BM-1197-induced apoptosis.
No full text<p>(A) Cells were transduced with lentiviral particles containing scrambled (SCR) or MCL1-specific shRNAs for 2 days, then treated with BM-1197 for 2 days. The growth-inhibitory activity of BM-1197 was assessed by WST assay. Data are representative of three independent experiments. (B) Cells were transduced with lentiviral particles containing scrambled (SCR) or MCL1-specific shRNAs for 2 days then treated with BM-1197 (100 nM) for 20 h before harvested for immunoblotting.</p
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