4,299 research outputs found

    Stellar Mass to Halo Mass Scaling Relation for X-ray Selected Low Mass Galaxy Clusters and Groups out to Redshift z1z\approx1

    Full text link
    We present the stellar mass-halo mass scaling relation for 46 X-ray selected low-mass clusters or groups detected in the XMM-BCS survey with masses 2×1013MM5002.5×1014M2\times10^{13}M_{\odot}\lesssim M_{500}\lesssim2.5\times10^{14}M_{\odot} at redshift 0.1z1.020.1\le z \le1.02. The cluster binding masses M500M_{500} are inferred from the measured X-ray luminosities \Lx, while the stellar masses MM_{\star} of the galaxy populations are estimated using near-infrared imaging from the SSDF survey and optical imaging from the BCS survey. With the measured \Lx\ and stellar mass MM_{\star}, we determine the best fit stellar mass-halo mass relation, accounting for selection effects, measurement uncertainties and the intrinsic scatter in the scaling relation. The resulting mass trend is MM5000.69±0.15M_{\star}\propto M_{500}^{0.69\pm0.15}, the intrinsic (log-normal) scatter is σlnMM500=0.360.06+0.07\sigma_{\ln M_{\star}|M_{500}}=0.36^{+0.07}_{-0.06}, and there is no significant redshift trend M(1+z)0.04±0.47M_{\star}\propto (1+z)^{-0.04\pm0.47}, although the uncertainties are still large. We also examine MM_{\star} within a fixed projected radius of 0.50.5~Mpc, showing that it provides a cluster binding mass proxy with intrinsic scatter of 93%\approx93\% (1σ\sigma in M500M_{500}). We compare our M=M(M500,z)M_{\star}=M_{\star}(M_{500}, z) scaling relation from the XMM-BCS clusters with samples of massive, SZE-selected clusters (M5006×1014MM_{500}\approx6\times10^{14}M_{\odot}) and low mass NIR-selected clusters (M5001014MM_{500}\approx10^{14}M_{\odot}) at redshift 0.6z1.30.6\lesssim z \lesssim1.3. After correcting for the known mass measurement systematics in the compared samples, we find that the scaling relation is in good agreement with the high redshift samples, suggesting that for both groups and clusters the stellar content of the galaxy populations within R500R_{500} depends strongly on mass but only weakly on redshift out to z1z\approx1.Comment: 15 pages, 10 figures. Accepted for publication in MNRA

    Effectiveness of influenza vaccination in patients with end-stage renal disease receiving hemodialysis: a population-based study.

    Get PDF
    BackgroundLittle is known on the effectiveness of influenza vaccine in ESRD patients. This study compared the incidence of hospitalization, morbidity, and mortality in end-stage renal disease (ESRD) patients undergoing hemodialysis (HD) between cohorts with and without influenza vaccination.MethodsWe used the insurance claims data from 1998 to 2009 in Taiwan to determine the incidence of these events within one year after influenza vaccination in the vaccine (N = 831) and the non-vaccine (N = 3187) cohorts. The vaccine cohort to the non-vaccine cohort incidence rate ratio and hazard ratio (HR) of morbidities and mortality were measured.ResultsThe age-specific analysis showed that the elderly in the vaccine cohort had lower hospitalization rate (100.8 vs. 133.9 per 100 person-years), contributing to an overall HR of 0.81 (95% confidence interval (CI) 0.72-0.90). The vaccine cohort also had an adjusted HR of 0.85 [95% CI 0.75-0.96] for heart disease. The corresponding incidence of pneumonia and influenza was 22.4 versus 17.2 per 100 person-years, but with an adjusted HR of 0.80 (95% CI 0.64-1.02). The vaccine cohort had lowered risks than the non-vaccine cohort for intensive care unit (ICU) admission (adjusted HR 0.20, 95% CI 0.12-0.33) and mortality (adjusted HR 0.50, 95% CI 0.41-0.60). The time-dependent Cox model revealed an overall adjusted HR for mortality of 0.30 (95% CI 0.26-0.35) after counting vaccination for multi-years.ConclusionsESRD patients with HD receiving the influenza vaccination could have reduced risks of pneumonia/influenza and other morbidities, ICU stay, hospitalization and death, particularly for the elderly

    Charmonium Spectrum from Quenched QCD with Overlap Fermions

    Get PDF
    We present preliminary results using overlap fermions for the charmonium spectrum, in particular for hyperfine splitting. Simulations are performed on 163×7216^3 \times 72 lattices, with Wilson gauge action at β=6.3345\beta=6.3345. Depending on how the scale is set, we obtain 104(5) MeV (using 1Pˉ1Sˉ1\bar{P}-1\bar{S}) or 88(4) MeV (using r0r_0=0.5 fm) for the hyperfine splitting.Comment: 3 pages, 5 fiugres. Talk presented at Lattice 2004 (heavy

    Relationship between Obesity-related Hormone Peptides and Quality of Life in Obese Women among Different Traditional Chinese Medicine Syndrome Groups

    Get PDF
    AbstractThe aim of this study was to explore the relationship between obesity-related hormone peptides and quality of life in obese women among different traditional Chinese medicine (TCM) syndrome groups (證型 zhèng xíng). 260 obese women met with age between 20 and 65years old and body mass index (BMI) ≧ 27kg/m2, were recruited. The participants filled out a questionnaire on obese TCM syndrome groups, which was designed by professional TCM doctors, and two questionnaires on quality of life (QOL), WHOQOL-BREF Taiwan version and MOS Short Form-12 (SF-12). Data of biochemical characteristics and obesity-related hormone peptides were collected at the same time. According to the responses provided, the obese subjects were classified into spleen deficiency with dampness encumbrance syndrome (脾虛濕阻證 pí xū shī zǔ zhèng; SDD), stomach heat with dampness encumbrance syndrome (胃熱濕阻證 wèi rè shī zǔ zhèng; SHD), liver depression and qi stagnation syndrome (肝鬱氣滯證 gān yù qì zhì zhèng; LDQ), dual spleen-kidney deficiency syndrome (脾腎兩虛證 pí shèn liǎng xū zhèng; SKD), yin deficiency with internal heat syndrome (陰虛內熱證 yīn xū nèi rè zhèng; YDI) and a control group. For physical conditions, SDD group had significantly higher means in weight and BMI compared with the control group. The insulin and leptin levels in SHD group were significantly higher than those in the control group. The LDQ group showed marked decrease in mental condition scores compared with the control group. This study found that obese women in the SDD group were fatter than those in the control group. SHD group might have greater influence on the regulation of obesity-related hormone peptides. The LDQ group had poor QOL than the control group. Analysis of TCM syndrome groups among obese women merits further investigation

    Stability of Solid State Reaction Fronts

    Full text link
    We analyze the stability of a planar solid-solid interface at which a chemical reaction occurs. Examples include oxidation, nitridation, or silicide formation. Using a continuum model, including a general formula for the stress-dependence of the reaction rate, we show that stress effects can render a planar interface dynamically unstable with respect to perturbations of intermediate wavelength

    Tunable nano Peltier cooling device from geometric effects using a single graphene nanoribbon

    Full text link
    Based on the phenomenon of curvature-induced doping in graphene we propose a class of Peltier cooling devices, produced by geometrical effects, without gating. We show how a graphene nanorib- bon laid on an array of curved nano cylinders can be used to create a targeted and tunable cooling device. Using two different approaches, the Nonequlibrium Green's Function (NEGF) method and experimental inputs, we predict that the cooling power of such a device can approach the order of kW/cm2, on par with the best known techniques using standard superlattice structures. The struc- ture proposed here helps pave the way toward designing graphene electronics which use geometry rather than gating to control devices.Comment: 12 pages, 5 figure

    Persistence of Japanese Encephalitis Virus Is Associated with Abnormal Expression of the Nonstructural Protein NS1 in Host Cells

    Get PDF
    AbstractPersistent infection with Japanese encephalitis virus (JEV) was established in murine neuroblastoma N18 cells, and the persistency has been maintained in cell culture for over 6 months. From the persistently infected cells, a clone named C2-2 was selected and expanded to form a stable cell line. The vast majority of C2-2 cells showed viral protein staining by immunofluorescence and continuously produced low levels of virus (103to 104PFU/ml) without marked cytopathic effects or cyclic variations. In addition to the wild-type viral proteins, truncated forms of the viral nonstructural protein 1 (NS1) as well as its derivative NS1′ were produced in C2-2 cells. Both truncated NS1 and NS1′ contain deletions at their N-termini; however, the analyses by RT–PCR and direct sequencing of the viral RNA failed to detect any truncations or mutations within the NS1 region, suggesting that NS1 truncation was a result of a unique posttranslational proteolytic cleavage of NS1 in the persistently infected cells. Similar but not identical truncation of NS1 was also observed in two other persistently infected cell lines established in Vero and DBT (murine astrocytoma) cells. However, viruses released from C2-2 cells did not produce truncated NS1 upon infection of N18 cells, suggesting that NS1 truncations were the result of virus–cell interaction in persistently infected cells. These data indicate a strong association between abnormal NS1 expression and JEV persistency. A probable involvement of dysfunctional NS1 in the establishment and/or maintenance of JEV persistency in tissue culture is discussed

    Baryon Content of Massive Galaxy Clusters (0.57 < z < 1.33)

    Get PDF
    We study the stellar, Brightest Cluster Galaxy (BCG) and intracluster medium (ICM) masses of 14 South Pole Telescope (SPT) selected galaxy clusters with median redshift z=0.9z=0.9 and median mass M500=6×1014MM_{500}=6\times10^{14}M_{\odot}. We estimate stellar masses for each cluster and BCG using six photometric bands spanning the range from the ultraviolet to the near-infrared observed with the VLT, HST and Spitzer. The ICM masses are derived from Chandra and XMM-Newton X-ray observations, and the virial masses are derived from the SPT Sunyaev-Zel'dovich Effect signature. At z=0.9z=0.9 the BCG mass MBCGM_{\star}^{\textrm{BCG}} constitutes 0.12±0.010.12\pm0.01% of the halo mass for a 6×1014M6\times10^{14}M_{\odot} cluster, and this fraction falls as M5000.58±0.07M_{500}^{-0.58\pm0.07}. The cluster stellar mass function has a characteristic mass M0=1011.0±0.1MM_{0}=10^{11.0\pm0.1}M_{\odot}, and the number of galaxies per unit mass in clusters is larger than in the field by a factor 1.65±0.21.65\pm0.2. Both results are consistent with measurements on group scales and at lower redshift. We combine our SPT sample with previously published samples at low redshift that we correct to a common initial mass function and for systematic differences in virial masses. We then explore mass and redshift trends in the stellar fraction (fstar), the ICM fraction (fICM), the cold baryon fraction (fc) and the baryon fraction (fb). At a pivot mass of 6×1014M6\times10^{14}M_{\odot} and redshift z=0.9z=0.9, the characteristic values are fstar=1.1±0.11.1\pm0.1%, fICM=9.6±0.59.6\pm0.5%, fc=10.4±1.210.4\pm1.2% and fb=10.7±0.610.7\pm0.6%. These fractions all vary with cluster mass at high significance, indicating that higher mass clusters have lower fstar and fc and higher fICM and fb. When accounting for a 15% systematic virial mass uncertainty, there is no statistically significant redshift trend at fixed mass in these baryon fractions. (abridged)Comment: Accepted for publication in MNRA

    Optimal Receiver Antenna Location in Indoor Environment Using Dynamic Differential Evolution and Genetic Algorithm

    Get PDF
    [[abstract]]Using the impulse responses of these multipath channels, the bit error rate (BER) performance for binary pulse amplitude modulation impulse radio ultra-wideband communication system is calculated. The optimization location of receiving antenna is investigated by dynamic differential evolution (DDE) and genetic algorithm (GA) to minimize the outage probability. Numerical results show that the performance for reducing BER and outage probability by DDE algorithm is better than that by GA.[[notice]]補正完畢[[incitationindex]]SCI[[booktype]]紙本[[booktype]]電子
    corecore