Search for sterile neutrinos in holographic dark energy cosmology: Reconciling Planck observation with the local measurement of the Hubble constant

We search for sterile neutrinos in the holographic dark energy cosmology by using the latest observational data. To perform the analysis, we employ the current cosmological observations, including the cosmic microwave background temperature power spectrum data from the Planck mission, the baryon acoustic oscillation measurements, the type Ia supernova data, the redshift space distortion measurements, the shear data of weak lensing observation, the Planck lensing measurement, and the latest direct measurement of $H_0$ as well. We show that, compared to the $\Lambda$CDM cosmology, the holographic dark energy cosmology with sterile neutrinos can relieve the tension between the Planck observation and the direct measurement of $H_0$ much better. Once we include the $H_0$ measurement in the global fit, we find that the hint of the existence of sterile neutrinos in the holographic dark energy cosmology can be given. Under the constraint of the all-data combination, we obtain $N_{\rm eff}= 3.76\pm0.26$ and $m_{\nu,\rm sterile}^{\rm eff}< 0.215\,\rm eV$, indicating that the detection of $\Delta N_{\rm eff}>0$ in the holographic dark energy cosmology is at the $2.75\sigma$ level and the massless or very light sterile neutrino is favored by the current observations.Comment: 10 pages, 4 figures; typos corrected, published in PR

Neutrinos in the holographic dark energy model: constraints from latest measurements of expansion history and growth of structure

The model of holographic dark energy (HDE) with massive neutrinos and/or dark radiation is investigated in detail. The background and perturbation evolutions in the HDE model are calculated. We employ the PPF approach to overcome the gravity instability difficulty (perturbation divergence of dark energy) led by the equation-of-state parameter $w$ evolving across the phantom divide $w=-1$ in the HDE model with $c<1$. We thus derive the evolutions of density perturbations of various components and metric fluctuations in the HDE model. The impacts of massive neutrino and dark radiation on the CMB anisotropy power spectrum and the matter power spectrum in the HDE scenario are discussed. Furthermore, we constrain the models of HDE with massive neutrinos and/or dark radiation by using the latest measurements of expansion history and growth of structure, including the Planck CMB temperature data, the baryon acoustic oscillation data, the JLA supernova data, the Hubble constant direct measurement, the cosmic shear data of weak lensing, the Planck CMB lensing data, and the redshift space distortions data. We find that $\sum m_\nu<0.186$ eV (95\% CL) and $N_{\rm eff}=3.75^{+0.28}_{-0.32}$ in the HDE model from the constraints of these data.Comment: 18 pages, 5 figures; revised version accepted for publication in JCA

Generating Chinese Couplets and Quatrain Using a Statistical Approach

PACLIC 23 / City University of Hong Kong / 3-5 December 200

Note On Certain Inequalities for Neuman Means

In this paper, we give the explicit formulas for the Neuman means $N_{AH}$, $N_{HA}$, $N_{AC}$ and $N_{CA}$, and present the best possible upper and lower bounds for theses means in terms of the combinations of harmonic mean $H$, arithmetic mean $A$ and contraharmonic mean $C$.Comment: 9 page

Optimization of Porous Insert Configuration in a Central Receiver Tube for Heat Transfer Enhancement

AbstractIn this paper, the heat transfer enhancement for convection heat transfer of turbulent flow in a central receiver tube filled with porous medium under non-uniform circumferential heat flux was numerically investigated. The effects of some parameters of porous medium (layout, thermal conductivity and porosity) and the Reynolds number (Re) on the thermal and thermo-hydraulic performance were discussed. The results showed that the enhanced receiver tube (ERT) with down-filling porous inserts and in-filling porous inserts have good thermal performance when the ratio of thermal conductivity of porous medium to working fluid (λs/λf) is less than 1,000. The ERT with out-filling porous inserts and up-filling porous inserts have good thermo-hydraulic performance when λs/λf >100. The porosity (ɛ) and Re also affect the thermal and thermo-hydraulic performance, the Nusselt number (Nu) and performance evaluation criteria (PEC) of heat transfer enhancement under constant pumping power of most kinds of ERTs decrease with the increase of ɛ, but the PEC of the ERT with in-filling porous inserts increases with the increase of ɛ. The Nu of all kinds of ERTs increases with the increase of Re, but the PEC decreases with the increase of Re

Expression of Wnt and NCX1 and its correlation with cardiomyocyte apoptosis in mouse with myocardial hypertrophy

AbstractObjectiveTo study the correlation between expression of Wnt and NCX1 and cardiomyocyte apoptosis in mouse with myocardial hypertrophy.MethodsC57B/16 male mice were given the subcutaneous injection of 1 mg/kg isoprenaline to build the myocardial hypertrophy model. After 14 d of model building, mice were executed by cervical vertebra luxation. The ratio of heart weight/body weight (HW/BW) and heart weight/tibia length (HW/TL) was observed and proved using HE staining that detected the size of cardiomyocytes. 40 male C57B/16 mice were randomly divided into the sham group (normal saline) and model group (isoprenaline), with 20 mice in each group. The terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling was applied to detect the cardiomyocyte apoptosis; while Western blot and immunohistochemistry were employed to detect the expression of Wnt and NCX1. Meanwhile, the correlation between these two proteins and cardiomyocyte apoptosis was explored.ResultsCompared with the sham group, the ratio of HW/BW and HW/TL was increased in the model group, as well as the bigger and hypertrophied cardiomyocytes, decreased number and increased apoptosis of cardiomyocytes, and increased positive expression of Wnt3a, Wnt5a and NCX1 in the cardiac muscle tissue. Besides, there was positive correlation between the expression of Wnt and NCX1 and the cardiomyocyte apoptosis.ConclusionThe expression of Wnt3a, Wnt5a and NCX1 in mouse with myocardial hypertrophy is increased and positively correlated with the cardiomyocyte apoptosis