Estimate black hole masses of AGNs using ultraviolet emission line properties

Based on the measured sizes of broad line region of the reverberation-mapping AGN sample, two new empirical relations are introduced to estimate the central black hole masses of radio-loud high-redshift ($z > 0.5$) AGNs. First, using the archival $IUE/HST$ spectroscopy data at UV band for the reverberation-mapping objects, we obtained two new empirical relations between the BLR size and \Mg/\C emission line luminosity. Secondly, using the newly determined black hole masses of the reverberation-mapping sample for calibration, two new relationships for determination of black hole mass with the full width of half maximum and the luminosity of \Mg/\C line are also found. We then apply the relations to estimate the black hole masses of AGNs in Large Bright Quasar Surveyq and a sample of radio-loud quasars. For the objects with small radio-loudness, the black hole mass estimated using the R_{\rm BLR} - L_{\eMg/\eC} relation is consistent with that from the $R_{BLR} - L_{3000\AA/1350 \AA}$ relation. But for radio-loud AGNs, the mass estimated from the R_{BLR} - L_{\eMg/\eC} relation is systematically lower than that from the continuum luminosity $L_{3000\AA/1350\AA}$. Because jets could have significant contributions to the UV/optical continuum luminosity of radio-loud AGNs, we emphasized again that for radio-loud AGNs, the emission line luminosity may be a better tracer of the ionizing luminosity than the continuum luminosity, so that the relations between the BLR size and UV emission line luminosity should be used to estimate the black hole masses of high redshift radio-loud AGNs.Comment: 19 pages, 10 figure

A Clustering-based Location Privacy Protection Scheme for Pervasive Computing

In pervasive computing environments, Location- Based Services (LBSs) are becoming increasingly important due to continuous advances in mobile networks and positioning technologies. Nevertheless, the wide deployment of LBSs can jeopardize the location privacy of mobile users. Consequently, providing safeguards for location privacy of mobile users against being attacked is an important research issue. In this paper a new scheme for safeguarding location privacy is proposed. Our approach supports location K-anonymity for a wide range of mobile users with their own desired anonymity levels by clustering. The whole area of all users is divided into clusters recursively in order to get the Minimum Bounding Rectangle (MBR). The exact location information of a user is replaced by his MBR. Privacy analysis shows that our approach can achieve high resilience to location privacy threats and provide more privacy than users expect. Complexity analysis shows clusters can be adjusted in real time as mobile users join or leave. Moreover, the clustering algorithms possess strong robustness.Comment: The 3rd IEEE/ACM Int Conf on Cyber, Physical and Social Computing (CPSCom), IEEE, Hangzhou, China, December 18-20, 201

Enhancement of the superconducting gap by nesting in CaKFe4As4 - a new high temperature superconductor

We use high resolution angle resolved photoemission spectroscopy and density functional theory with experimentally obtained crystal structure parameters to study the electronic properties of CaKFe4As4. In contrast to related CaFe2As2 compounds, CaKFe4As4 has high Tc of 35K at stochiometric composition. This presents unique opportunity to study properties of high temperature superconductivity of iron arsenic superconductors in absence of doping or substitution. The Fermi surface consists of three hole pockets at $\Gamma$ and two electron pockets at the $M$ point. We find that the values of the superconducting gap are nearly isotropic, but significantly different for each of the FS sheets. Most importantly we find that the overall momentum dependence of the gap magnitudes plotted across the entire Brillouin zone displays a strong deviation from the simple cos(kx)cos(ky) functional form of the gap function, proposed in the scenario of the Cooper-pairing driven by a short range antiferromagnetic exchange interaction. Instead, the maximum value of the gap is observed for FS sheets that are closest to the ideal nesting condition in contrast to the previous observations in some other ferropnictides. These results provide strong support for the multiband character of superconductivity in CaKFe4As4, in which Cooper pairing forms on the electron and the hole bands interacting via dominant interband repulsive interaction, enhanced by FS nesting}.Comment: 5 pages, 4 figure

Exploring the X-ray and γ-ray properties of the redback millisecond pulsar PSR J1723-2837

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Morphometric variation in the pusillus group of the genus Rhinolophus (Mammalia: Chiroptera: Rhinolophidae) in East Asia.

Based on 203 specimens belonging to the Rhinolophus "pusillus group" (Mammalia: Chiroptera: Rhinolophidae), univariate and multivariate morphometric analyses using 19 characters were performed to assess the confused species taxonomy. The results indicated that R. pusillus (including calidus, parcus, and szechuanus) in the continental region and Hainan Island of China and "R. cornutus" in Japan are morphologically divergent species. Rhinolophus cornutus should be further split into R. cornutus (including orii, pumilus, and miyakonis) in the main islands of Japan, the Amami and Okinawa Group of the central Ryukyu Archipelago, and Miyako Group of the southern Ryukyus; and R. perditus and R. imaizumii from the Yaeyama Group in the southern Ryukyus. Rhinolophus monoceros from Taiwan is morphologically more similar to species in Japan than to R. pusillus. In addition to R. pusillus, another form that is morphologically similar to species in Japan was recognized from Langzhong in Sichuan Province; this may represent an undescribed species, and further examination is necessary to determine its taxonomic status. Specimens from Guang'an in Sichuan Province, China, are also different from the others, and are characterized by the smallest skull size. Although further studies are required, these specimens were tentatively identified as R. subbadius

Gallium-Doped Li7La3Zr2O12 Garnet-Type Electrolytes with High Lithium-Ion Conductivity

Owing to their high conductivity, crystalline Li7–3xGaxLa3Zr2O12 garnets are promising electrolytes for all-solid-state lithium-ion batteries. Herein, the influence of Ga doping on the phase, lithium-ion distribution, and conductivity of Li7–3xGaxLa3Zr2O12 garnets is investigated, with the determined concentration and mobility of lithium ions shedding light on the origin of the high conductivity of Li7–3xGaxLa3Zr2O12. When the Ga concentration exceeds 0.20 Ga per formula unit, the garnet-type material is found to assume a cubic structure, but lower Ga concentrations result in the coexistence of cubic and tetragonal phases. Most lithium within Li7–3xGaxLa3Zr2O12 is found to reside at the octahedral 96h site, away from the central octahedral 48g site, while the remaining lithium resides at the tetrahedral 24d site. Such kind of lithium distribution leads to high lithium-ion mobility, which is the origin of the high conductivity; the highest lithium-ion conductivity of 1.46 mS/cm at 25 °C is found to be achieved for Li7–3xGaxLa3Zr2O12 at x = 0.25. Additionally, there are two lithium-ion migration pathways in the Li7–3xGaxLa3Zr2O12 garnets: 96h-96h and 24d-96h-24d, but the lithium ions transporting through the 96h-96h pathway determine the overall conductivity

Kinetics and Mechanism Study of Competitive Inhibition of Jack-Bean Urease by Baicalin

Baicalin (BA) is the principal component of Radix Scutellariae responsible for its pharmacological activity. In this study, kinetics and mechanism of inhibition by BA against jack-bean urease were investigated for its therapeutic potential. It was revealed that the IC50 of BA against jack-bean urease was 2.74 ± 0.51 mM, which was proved to be a competitive and concentration-dependent inhibition with slow-binding progress curves. The rapid formation of initial BA-urease complex with an inhibition constant of Ki=3.89 × 10−3 mM was followed by a slow isomerization into the final complex with an overall inhibition constant of Ki*=1.47×10-4 mM. High effectiveness of thiol protectors against BA inhibition indicated that the strategic role of the active-site sulfhydryl group of the urease was involved in the blocking process. Moreover, the inhibition of BA was proved to be reversible due to the fact that urease could be reactivated by dithiothreitol but not reactant dilution. Molecular docking assay suggested that BA made contacts with the important activating sulfhydryl group Cys-592 residues and restricted the mobility of the active-site flap. Taken together, it could be deduced that BA was a competitive inhibitor targeting thiol groups of urease in a slow-binding manner both reversibly and concentration-dependently, serving as a promising urease inhibitor for treatments on urease-related diseases