595 research outputs found

    The Variation of Gas Mass Distribution in Galaxy Clusters: Effects of Preheating and Shocks

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    We investigate the origin of the variation of the gas mass fraction in the core of galaxy clusters, which was indicated by our work on the X-ray fundamental plane. The adopted model supposes that the gas distribution characterized by the slope parameter is related to the preheated temperature. Comparison with observations of relatively hot (~> 3 keV) and low redshift clusters suggests that the preheated temperature is about 0.5-2 keV, which is higher than expected from the conventional galactic wind model and possibly suggests the need for additional heating such as quasars or gravitational heating on the largest scales at high redshift. The dispersion of the preheated temperature may be attributed to the gravitational heating in subclusters. We calculate the central gas fraction of a cluster from the gas distribution, assuming that the global gas mass fraction is constant within a virial radius at the time of the cluster collapse. We find that the central gas density thus calculated is in good agreement with the observed one, which suggests that the variation of gas mass fraction in cluster cores appears to be explained by breaking the self-similarity in clusters due to preheated gas. We also find that this model does not change major conclusions on the fundamental plane and its cosmological implications obtained in previous papers, which strongly suggests that not only for the dark halo but also for the intracluster gas the core structure preserves information about the cluster formation.Comment: 17 pages, to be published in Ap

    In Vivo Studies on Fast and Slow Muscle Fibers in Cat Extraocular Muscles

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    In anesthetized in vivo preparations, responses of two types of extraocular muscle fibers have been studied. The small, multiply innervated slow fibers have been shown to be capable of producing propagated impulses, and thus have been labeled slow multi-innervated twitch fibers. Fast and slow multi-innervated twitch fibers are distinguished by impulse conduction velocities, by ranges of membrane potentials, by amplitudes and frequencies of the miniature end plate potentials, by responses to the intravenous administration of succinylcholine, by the frequency of stimulation required for fused tetanus, and by the velocities of conduction of the nerve fibers innervating each of the muscle fiber types

    Mass Spectra-Based Framework for Automated Structural Elucidation of Metabolome Data to Explore Phytochemical Diversity

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    A novel framework for automated elucidation of metabolite structures in liquid chromatography–mass spectrometer metabolome data was constructed by integrating databases. High-resolution tandem mass spectra data automatically acquired from each metabolite signal were used for database searches. Three distinct databases, KNApSAcK, ReSpect, and the PRIMe standard compound database, were employed for the structural elucidation. The outputs were retrieved using the CAS metabolite identifier for identification and putative annotation. A simple metabolite ontology system was also introduced to attain putative characterization of the metabolite signals. The automated method was applied for the metabolome data sets obtained from the rosette leaves of 20 Arabidopsis accessions. Phenotypic variations in novel Arabidopsis metabolites among these accessions could be investigated using this method

    Properties of the Brightest Cluster Galaxy and Its Host Cluster

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    We investigate the relation between the properties of Brightest Cluster Galaxies (BCGs) and those of their host clusters. To quantify the properties of cluster hot gas, we employ the parameter ZZ of the fundamental plane of X-ray clusters. It is found that the offset of the BCG from the peak of cluster X-ray emission is larger for smaller ZZ clusters. The parameter ZZ (not the redshift {\it z}), which mainly depends on virial density ρvir\rho_{\rm {vir}}, is considered to represent the formation epoch of a cluster. We thus consider that the offset of the BCG is correlated with the dynamical equilibrium state of its host cluster. On the contrary, no significant correlation is found between the absolute optical magnitude of the BCG and the parameter ZZ. If the extreme brightness of the BCG is mainly acquired in the course of cluster evolution by environmental effect, BCGs are expected to be brighter in large ZZ clusters. Our result is not consistent with this simplified view. On the contrary, it is possible that the extreme brightness of the BCG is likely to be determined in the early history of cluster collapse.Comment: 18 pages, 9 figures, accepted for publication in Ap

    Biogenesisi of liver-specific microRNA, miR-122

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    Modelling the Shimokita deep coalbed biosphere over deep geological time : Starvation, stimulation, material balance and population models

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    ACKNOWLEDGEMENTS The authors are grateful to all crews, drilling team members, lab technicians and scientists on the drilling vessel Chikyu for supporting core sampling and on board measurements during the Chikyu shakedown cruise CK06‐06 and the Integrated Ocean Drilling Program (IODP) Expedition 337. This work was supported in part by the Japan Society for the Promotion of Science (JSPS) Strategic Fund for Strengthening Leading‐Edge Research and Development (to F.I. and JAMSTEC), the JSPS Funding Program for Next Generation World‐Leading Researchers (NEXT Program, no. GR102 to F.I.). All shipboard and shore‐based data presented in this manuscript are archived and publicly available on‐line in either the IODP Expedition 337 Proceedings through the J‐CORES (http://sio7.jamstec.go.jp/j-cores.data/337/C0020A/), the PANGAEA database (www.pangaea.de, doi.org/10.1594/PANGAEA.845984), or Inagaki et al., 2015, respectively. Petromod Basin Modelling software was provided by Schlumberger to the University of Aberdeen. This is a contribution to the Deep Carbon Observatory (DCO). SAB wishes to thank HSB for support preparing the manuscript. DATA AVAILABILITY STATEMENT All shipboard and shore‐based data presented in this manuscript are archived and publicly available on‐line in either the IODP Expedition 337 Proceedings through the J‐CORES (http://sio7.jamstec.go.jp/j-cores.data/337/C0020A/), the PANGAEA database (www.pangaea.de, https://doi.org/10.1594/PANGAEA.845984), or Inagaki et al., 2015, respectively.Peer reviewedPostprin
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