Reconsideration of the QCD corrections to the ηc\eta_c decays into light hadrons using the principle of maximum conformality

In the paper, we analyze the $\eta_c$ decays into light hadrons at the next-to-leading order QCD corrections by applying the principle of maximum conformality (PMC). The relativistic correction at the ${\cal{O}}(\alpha_s v^2)$-order level has been included in the discussion, which gives about $10\%$ contribution to the ratio $R$. The PMC, which satisfies the renormalization group invariance, is designed to obtain a scale-fixed and scheme-independent prediction at any fixed order. To avoid the confusion of treating $n_f$-terms, we transform the usual $\overline{\rm MS}$ pQCD series into the one under the minimal momentum space subtraction scheme. To compare with the prediction under conventional scale setting, $R_{\rm{Conv,mMOM}-r}= \left(4.12^{+0.30}_{-0.28}\right)\times10^3$, after applying the PMC, we obtain $R_{\rm PMC,mMOM-r}=\left(6.09^{+0.62}_{-0.55}\right) \times10^3$, where the errors are squared averages of the ones caused by $m_c$ and $\Lambda_{\rm mMOM}$. The PMC prediction agrees with the recent PDG value within errors, i.e. $R^{\rm exp}=\left(6.3\pm0.5\right)\times10^3$. Thus we think the mismatching of the prediction under conventional scale-setting with the data is due to improper choice of scale, which however can be solved by using the PMC.Comment: 5 pages, 2 figure

Outflows from active galactic nuclei: The BLR-NLR metallicity correlation

The metallicity of active galactic nuclei (AGNs), which can be measured by emission line ratios in their broad and narrow line regions (BLRs and NLRs), provides invaluable information about the physical connection between the different components of AGNs. From the archival databases of the International Ultraviolet Explorer, the Hubble Space Telescope and the Sloan Digital Sky Survey, we have assembled the largest sample available of AGNs which have adequate spectra in both the optical and ultraviolet bands to measure the narrow line ratio [N II]/H{\alpha} and also, in the same objects, the broad-line N V/C IV ratio. These permit the measurement of the metallicities in the NLRs and BLRs in the same objects. We find that neither the BLR nor the NLR metallicity correlate with black hole masses or Eddington ratios, but there is a strong correlation between NLR and BLR metallicities. This metallicity correlation implies that outflows from BLRs carry metal-rich gas to NLRs at characteristic radial distances of ~ 1.0 kiloparsec. This chemical connection provides evidence for a kinetic feedback of the outflows to their hosts. Metals transported into the NLR enhance the cooling of the ISM in this region, leading to local star formation after the AGNs turn to narrow line LINERs. This post-AGN star formation is predicted to be observable as an excess continuum emission from the host galaxies in the near infrared and ultraviolet, which needs to be further explored.Comment: 19 pages, 13 figures, 3 tables. Accepted for publication at MNRA

Fully integrated InGaAs/InP single-photon detector module with gigahertz sine wave gating

InGaAs/InP single-photon avalanche diodes (SPADs) working in the regime of GHz clock rates are crucial components for the high-speed quantum key distribution (QKD). We have developed for the first time a compact, stable and user-friendly tabletop InGaAs/InP single-photon detector system operating at a 1.25 GHz gate rate that fully integrates functions for controlling and optimizing SPAD performance. We characterize the key parameters of the detector system and test the long-term stability of the system for continuous operation of 75 hours. The detector system can substantially enhance QKD performance and our present work paves the way for practical high-speed QKD applications.Comment: 11 pages, 6 figures. Accepted for publication in Review of Scientific Instrument

Poly[di-μ2-chlorido-μ2-(1,4-dioxane-κ2 O:O′)-cadmium(II)]

In the title complex, [CdCl2(C4H8O2)]n, two different CdII ions are present, one in a general position and one with site symmetry 2. The CdII ions are coordinated by two O atoms from two 1,4-dioxane ligands and four chloride anions in a slightly distorted octa­hedral geometry and is connected to neighboring CdII ions by two bridging chloride anions, generating infinite linear chains along the a axis. These chains are further inter­connected by bridging 1,4-dioxane ligands, affording a three-dimensional network

Wortmannin as Targeted Therapeutic Agent for the Treatment of Triple-Negative Breast Cancer

Purpose: To investigate the inhibitory effect of wortmannin on inhibition of BT-20 and BT-474 breast cancer cells in Athymic nu/nu mice model.Methods: Forty Athymic nu/nu mice were randomly assigned to 4 groups of 10 each, namely, BT-20 control, BT-20 treatment, BT-474 control and BT-474 treatment groups. The mice were injected with 2.5 x 105 BT-20 and BT-474 cells under anesthesia. Those in the treatment groups were given wortmannin (7 mg/kg) in DMSO daily intraperitoneally whereas the animals in control groups received an equal volume of DMSO for 21 days after the cancer attained palpable stage. Western blot analysis was carried out using enhanced chemiluminescence reagent while Protean IEF cell unit was used for 1-D electrophoresis.Results: The results showed a significant decrease in the growth of the tested cancer cell lines on treatment with wortmannin at 7 mg/kg daily for 21 days. The volume of tumor in the treatment group was reduced to 42.72 ± 9.45 compared to 79.43 ± 17.11 mm3 in the control group after 21 days treatment (p < 0.005). It also changed the expression of microRNA in BT-20 cells. Exposure of BT-20 cells to wortmannin for 24 h resulted in the altered expression of proteomes. Wortmannin treatment increased the expression of miRs including miR 19a/b, 22, 29b/c, 181c/d, 195 and 663. Western blot data showed increase in the expression of NME1 (NM23 H1) and reduction in the expression of vimentin after treatment with wortmannin.Conclusion: Wortmannin can be of benefit in the treatment of human breast cancer.Keywords: Wortmannin, Vimentin, Tumor growth, Expression of microRNA, Proteome

Cobalt and Nickel Complexes Bearing 2-(2-pyridyl)-Benzimidazole: Synthesis and Ethylene Oligomerization

A series of cobalt and nickel complexes MLX2 (M=Co or Ni, X=Cl) bearing 2-(2-pyridyl)benzimidazole ligands were synthesized. Treatment of the complexes with methylaluminoxane (MAO) leads to active catalysts for ethylene oligomerization. The oligomers were olefins from C2 to C6

Cobalt and Nickel Complexes Bearing 2,6-Bis(imino)phenoxy Ligands:Synthesis and Ethylene Oligomerization Study

A series of new cobalt and nickel complexes MLX2 (M = Co or Ni, X = Cl) bearing 2,6-bis(imino)phenoxy ligands have been synthesized. Treatment of the complexes with methylaluminoxane (MAO) leads to active catalysts for ethylene oligomerization. The oligomers are olefins from C4 to C6

Magnetic light amplification by stimulated emission of radiation in subwavelength systems of a dielectric cavity and magnetic quantum emitters

We propose a magnetic laser in a subwavelength system consisting of a high-refractive-index dielectric cavity and an active medium formed by magnetic quantum emitters. Stimulated emissions of magnetic quantum emitters induced by their coherent interactions with quantized magnetic fields of a cavity are theoretically considered. The condition to archive such a magnetic laser is obtained. Numerical results show that magnetic lasers are feasible in some realistic systems, for example, a silicon disk of high-quality whispering gallery modes with embedded emitters. Furthermore, the competitions between the electric interaction and magnetic one in terms of their Purcell factors are also considered in some magnetic laser achievable systems. In a wavelength-scale silicon block of a high-order magnetic mode, the ratio of magnetic Purcell factor to the electric one can reach more than ~10^3 large. Our results open up ways to enhanced magnetic light-matter interactions.Comment: 21 pages, 5 figure