Suzaku View of the Neutron Star in the Dipping Source 4U 1822−-37

The dipping X-ray source 4U 1822$-$37 was observed by Suzaku on 2006 Octrober 20 for a net exposure of 37 ks. The source was detected with the XIS at a 1-10 keV flux of 5.5$\times10^{-10}$ erg cm$^{-2}$ s$^{-1}$, and with the HXD (HXD-PIN) at a 10-50 keV flux of 8.9$\times10^{-10}$ erg cm$^{-2}$ s$^{-1}$. With HXD-PIN, the pulsation was detected at a barycentric period of 0.592437 s, and its change rate was reconfirmed as $-2.43\times$10$^{-12}$ s s$^{-1}$. The 1-50 keV spectra of 4U 1822-37 were found to be very similar to those of Her X-1 in the slopes, cutoff and iron lines. Three iron lines (Fe K$\alpha$, Fe XXV, and Fe XXVI) were detected, on top of a 1-50 keV continuum that is described by an NPEX model plus a soft blackbody. In addition, a cyclotron resonance scattering feature was detected significantly ($>99\%$ confidence), at an energy of 33$\pm$2 keV with a depth of 0.4$^{+0.6}_{-0.3}$. Therefore, the neutron star in this source is concluded to have a strong magnetic field of 2.8$\times10^{12}$ G. Further assuming that the source has a relatively high intrinsic luminosity of several times 10$^{37}$ erg s$^{-1}$, its spectral and timing properties are consistently explained

The Nature of the Stable Soft X-ray Emissions in Several Types of Active Galactic Nuclei Observed by Suzaku

To constrain the origin of the soft X-ray excess phenomenon seen in many active galactic nuclei, the intensity-correlated spectral analysis, developed by Noda et al. (2011b) for Markarian 509, was applied to wide-band (0.5-45 keV) Suzaku data of five representative objects with relatively weak reflection signature. They are the typical bare-nucleus type 1 Seyfert Fairall 9, the bright and typical type 1.5 Seyfert MCG-2-58-22, 3C382 which is one of the X-ray brightest broad line radio galaxies, the typical Seyfert-like radio loud quasar 4C+74.26, and the X-ray brightest radio quiet quasar MR2251-178. In all of them, soft X-ray intensities in energies below 3 keV were tightly correlated with that in 3-10 keV, but with significant positive offsets. These offsets, when calculated in finer energy bands, define a stable soft component in 0.5-3 keV. In each object, this component successfully explained the soft excess above a power-law fit. These components were interpreted in several alternative ways, including a thermal Comptonization component which is independent of the dominant power-law emission. This interpretation, considered physically most reasonable, is discussed from a viewpoint of Multi-Zone Comptonization, which was proposed for the black hole binary Cygnus X-1 (Makishima et al. 2008).Comment: 18 pages, 12 figures, 7 table

RXTE Observations of the Low-Mass X-Ray Binary 4U 1608-522 in Upper-Banana State

To investigate the physics of mass accretion onto weakly-magnetized neutron stars, 95 archival RXTE datasets of an atoll source 4U 1608-522, acquired over 1996-2004 in so-called upper-banana state, were analyzed. The object meantime exhibited 3-30 keV luminosity in the range of <~ 10^35 - 4 x 10^37 erg s^-1, assuming a distance of 3.6 kpc. The 3-30 keV PCA spectra, produced one from each dataset, were represented successfully with a combination of a soft and a hard component, of which the presence was revealed in a model-independent manner by studying spectral variations among the observations. The soft component is expressed by so-called multi-color disk model with a temperature of ~1.8 keV, and is attributed to the emission from an optically-thick standard accretion disk. The hard component is a blackbody emission with a temperature of ~2.7 keV, thought to be emitted from the neutron-star surface. As the total luminosity increases, a continuous decrease was observed in the ratio of the blackbody luminosity to that of the disk component. This property suggests that the matter flowing through the accretion disk gradually becomes difficult to reach the neutron-star surface, presumably forming outflows driven by the increased radiation pressure. On time scales of hours to days, the overall source variability was found to be controlled by two independent variables; the mass accretion rate, and the innermost disk radius which changes both physically and artificially.Comment: ApJ accepted, 29 pages, 9 figure

TriMEDB: A database to integrate transcribed markers and facilitate genetic studies of the tribe Triticeae

<p>Abstract</p> <p>Background</p> <p>The recent rapid accumulation of sequence resources of various crop species ensures an improvement in the genetics approach, including quantitative trait loci (QTL) analysis as well as the holistic population analysis and association mapping of natural variations. Because the tribe Triticeae includes important cereals such as wheat and barley, integration of information on the genetic markers in these crops should effectively accelerate map-based genetic studies on Triticeae species and lead to the discovery of key loci involved in plant productivity, which can contribute to sustainable food production. Therefore, informatics applications and a semantic knowledgebase of genome-wide markers are required for the integration of information on and further development of genetic markers in wheat and barley in order to advance conventional marker-assisted genetic analyses and population genomics of Triticeae species.</p> <p>Description</p> <p>The Triticeae mapped expressed sequence tag (EST) database (TriMEDB) provides information, along with various annotations, regarding mapped cDNA markers that are related to barley and their homologues in wheat. The current version of TriMEDB provides map-location data for barley and wheat ESTs that were retrieved from 3 published barley linkage maps (the barley single nucleotide polymorphism database of the Scottish Crop Research Institute, the barley transcript map of Leibniz Institute of Plant Genetics and Crop Plant Research, and HarvEST barley ver. 1.63) and 1 diploid wheat map. These data were imported to CMap to allow the visualization of the map positions of the ESTs and interrelationships of these ESTs with public gene models and representative cDNA sequences. The retrieved cDNA sequences corresponding to each EST marker were assigned to the rice genome to predict an exon-intron structure. Furthermore, to generate a unique set of EST markers in Triticeae plants among the public domain, 3472 markers were assembled to form 2737 unique marker groups as contigs. These contigs were applied for pairwise comparison among linkage maps obtained from different EST map resources.</p> <p>Conclusion</p> <p>TriMEDB provides information regarding transcribed genetic markers and functions as a semantic knowledgebase offering an informatics facility for the acceleration of QTL analysis and for population genetics studies of Triticeae.</p

Accretion Geometry of the Low-Mass X-ray Binary Aquila X-1 in the Soft and Hard States

The neutron-star Low-Mass X-ray Binary Aquila X-1 was observed seven times in total with the Suzaku X-ray observatory from September 28 to October 30 in 2007, in the decaying phase of an outburst. In order to constrain the flux-dependent accretion geometry of this source over wider energy bands than employed in most of previous works, the present study utilized two out of the seven data sets. The 0.8-31 keV spectrum on September 28, taken with the XIS and HXD-PIN for an exposure of 13.8 ks, shows an absorbed 0.8-31 keV flux of $3.6\times 10^{-9}$ erg s$^{-1}$ cm$^{-2}$, together with typical characteristics of the soft state of this type of objects. The spectrum was successfully explained by an optically-thick disk emission plus a Comptonized blackbody component. Although these results are in general agreement with previous studies, the significance of a hard tail recently reported using the same data was inconclusive in our analysis. The spectrum acquired on October 9 for an exposure of 19.7 ks was detected over a 0.8-100 keV band with the XIS, HXD-PIN, and HXD-GSO, at an absorbed flux of $8.5\times 10^{-10}$ erg s$^{-1}$ cm$^{-2}$ (in 0.8-100 keV). It shows characteristics of the hard state, and was successfully explained by the same two continuum components but with rather different parameters including much stronger thermal Comptonization, of which the seed photon source was identified with blackbody emission from the neutron-star surface. As a result, the accretion flow in the hard state is inferred to take a form of an optically-thick and geometrically-thin disk down to a radius of $21\pm 4$ km from the neutron star, and then turn into an optically-thin nearly-spherical hot flow.Comment: PASJ in publish. 12 pages including 16 figure

Influence of local antigen exposure dose in the upper respiratory tract on sensitization with cedar pollen

ABSTRACTBackgroundAn increase in Japanese cedar pollen counts is the probable reason for the increase in the number of Japanese cedar hay fever patients. To determine whether local antigen exposure dose affects sensitization with cedar pollen, we compared serum levels of specific IgE antibody in rats exposed to higher and lower doses of cedar pollen antigen through the nose.MethodsSerum levels of cedar pollen-specific IgE antibody was examined in Brown Norway rats exposed to a higher dose of (20 μg) Cry j I, a lower dose (2 μg) of Cry j I or no dose for 6 months. Serum levels of cedar pollen-specific IgE antibody were measured by reverse IgE-capture ELISA. The extent of local eosinophilia in the nasal, laryngeal and tracheal mucosa of rats exposed higher and lower doses of cedar pollen antigen and controls were observed microscopically.ResultsThe mean serum levels of specific IgE antibody in rats exposed to the higher dose were significantly higher than those in rats exposed to the lower dose, and the mean levels in rats in the lower-dose group were significantly higher than in controls. The extent of eosinophilia in the nasal mucosa in the higher-dose group was significantly greater than in controls, but no significant differences between the lower-dose group and controls were found. The extent of eosinophilia in the laryngeal mucosa in the higher-dose group was significantly greater than that in the lower-dose group and in controls. Only a small degree of eosinophilia was observed in the trachea of all three groups.ConclusionsLocal exposure dose of the upper airway to cedar pollen may affect sensitization

Plaque Vulnerability in Internal Carotid Arteries with Positive Remodeling

Background: This study aimed to evaluate the efficacy of assessing positive remodeling for predicting future stroke events in the internal carotid artery. We therefore assessed narrowing of the carotid artery lumen using multidetector-row computer tomography (MDCT) angiography and carotid plaque characteristics using black-blood (BB) magnetic resonance (MR). Methods: We retrospectively selected 17 symptomatic and 11 asymptomatic lesions with luminal narrowing >50%. We compared remodeling parameters of luminal stenosis (remodeling ratio, RR/remodeling index, RI) using MDCT and MR intensities of atherosclerotic plaque contents using the BB technique (relative signal intensity, rSI). We also confirmed the validity of the relationship between MR intensity and atherosclerotic plaque contents by histology. The levels of biological markers related to vessel atherosclerosis were measured. Results: Plaque lesions with positive remodeling in carotid arteries were associated with a significantly higher prevalence of stroke compared with plaques with negative remodeling (p Conclusions: The results of this study suggest that the combined analysis of RR, RI and rSI could potentially help to predict future stroke events