4,321 research outputs found

    Glucocorticoids Inhibit Sodium Depletion-induced Salt Appetite in Rat

    Get PDF
    Glucocorticoids, produced in adrenal cortex, exert potent natriuretic and diuretic actions in the kidney. Recently, it has been found that glucocorticoids could upregulate the expression of natriuretic peptide receptor A (NPR-A), the primary receptor of atrial natriuretic peptide, in the hypothalamus of the rat. Consequently, systemic administration of glucocorticoid could block dehydration-induced water intake by activation hypothalamic NPR-A. We describe here glucocorticoids could inhibit sodium intake when administrated systemically in conscious, salt-depleted rats; an effect which was strong and long-lasting. The study provided further evidence for the actions of glucocorticoids on central nervous system, which together with their established renal actions coordinated to normalize extracellular fluid volume

    Glucocorticoids Inhibit Sodium Depletion-induced Salt Appetite in Rat

    Get PDF

    Direct CP violation in τ±K±ρ0(ω)ντK±π+πντ\tau^\pm\rightarrow K^\pm \rho^0 (\omega)\nu_\tau \rightarrow K^\pm \pi^+\pi^-\nu_\tau

    Get PDF
    We study the direct CP violation in the τ±K±ρ0(ω)ντK±π+πντ\tau^\pm\rightarrow K^\pm \rho^0 (\omega)\nu_\tau \rightarrow K^\pm \pi^+\pi^-\nu_\tau decay process in the Standard Model. An interesting mechanism involving the charge symmetry violating mixing between ρ0\rho^0 and ω\omega is applied to enlarge the CP asymmetry. With this mechanism, the maximum differential and localized integrated CP asymmetries can reach (5.61.7+2.9)×1012-(5.6^{+2.9}_{-1.7})\times10^{-12} and 6.33.3+2.4×10116.3^{+2.4}_{-3.3}\times 10^{-11}, respectively, which still leave plenty room for CP-violating New Physics to be discovered through this process

    Transport of the Saharan dust air plumes over the tropical North Atlantic from FORMOSAT–3/COSMIC observation

    Get PDF
    AbstractLong–range transport of the Saharan dust plumes during May–August of each year is a prominent feature over the tropical North Atlantic. Observations of temperature profiles are highly desirable in clarifying the impacts of the Saharan dust plumes over the tropical North Atlantic. In this work we evaluate positive temperature anomalies (inversions in the lower troposphere) in the North Atlantic low troposphere originating from Western Africa, and to examine the correspondence of these events to Saharan dust plumes, using several temperature sources and satellite–detected measurements of Aerosol Index. We combine profiles of temperature observations from FORMOSAT–3/COSMIC (F3C) with aerosol observations from Ozone Monitoring Instrument (OMI) to provide direct evidence of the Saharan dust plumes modifying environmental stability. The F3C observations show good profile measurements compared with the radiosondes in the lower troposphere, with the average temperature differences less than 0.5K. The F3C results were also compared with the Aqua Advanced Infrared Radiation Sounder (AIRS) and meteorological analyses from the National Centers for Environmental Predictions (NCEP), the United Kingdom Met Office (UKMO), and the European Centre for Medium Range Weather Forecast (ECMWF). Our results show that hot air plumes are associated with the Saharan dust plumes during their transport across the tropical North Atlantic. There were eleven distinctive hot air plumes during May–August 2007 and 2008, respectively. These hot air plumes increase environmental temperatures below 5–km altitudes, with the maximum increase of 1–2K around 2–km. This leads to increase of environmental stability below 2–km altitudes and decrease of environmental stability between 2– and 5–km altitudes. By changing the vertical distribution of environmental stability, the Saharan dust plumes act to stabilize environmental air below 2–km while destabilize environmental air from 2– to 5–km altitudes. These results are distinctively presented in the F3C and AIRS observations but less obvious in the meteorological analyses

    Observations on shifted cumulative regulation

    Get PDF
    A response to Dynamic cumulative activity of transcription factors as a mechanism of quantitative gene regulation by F He, J Buer, AP Zeng and R Balling. Genome Biol 2007, 8:R181

    The Quasinormal Modes and Isospectrality of Bardeen (Anti-) de Sitter Black Holes

    Full text link
    Black holes (BHs) exhibiting coordinate singularities but lacking essential singularities throughout the entire spacetime are referred to as regular black holes (RBHs). The initial formulation of RBHs was presented by Bardeen, who considered the Einstein equation coupled with a nonlinear electromagnetic field. In this study, we investigate the gravitational perturbations, including the axial and polar sectors, of the Bardeen (Anti-) de Sitter black holes. We derive the master equations with source terms for both axial and polar perturbations, and subsequently compute the quasinormal modes (QNMs) through numerical methods. For the Bardeen de Sitter black hole, we employ the 6th-order WKB approach. The numerical results reveal that the isospectrality is broken in this case. Conversely, for Bardeen Anti-de Sitter black holes, the QNM frequencies are calculated by using the HH method.Comment: 12 pages, 6 figures, 4 table
    corecore