Dynamics of entanglement for a two-parameter class of states in a qubit-qutrit system

We investigate the dynamics of entanglement for a two-parameter class of states in a hybrid qubit-qutrit system under the influence of various dissipative channels. Our results show that entanglement sudden death (ESD) is a general phenomenon and it usually takes place in a qubit-qutrit system interacting with various noisy channels, not only the case with dephasing and depolarizing channels observed by others. ESD can only be avoided for some initially entangled states under some particular noisy channels. Moreover, the environment affects the entanglement and the coherence of the system in very different ways.Comment: 9 pages, 6 figures, 1 table. A negligible error for type on Eq(7) is correcte

Single-photon-assisted entanglement concentration of a multi-photon system in a partially entangled W state with weak cross-Kerr nonlinearity

We propose a nonlocal entanglement concentration protocol (ECP) for $N$-photon systems in a partially entangled W state, resorting to some ancillary single photons and the parity-check measurement based on cross-Kerr nonlinearity. One party in quantum communication first performs a parity-check measurement on her photon in an $N$-photon system and an ancillary photon, and then she picks up the even-parity instance for obtaining the standard W state. When she obtains an odd-parity instance, the system is in a less-entanglement state and it is the resource in the next round of entanglement concentration. By iterating the entanglement concentration process several times, the present ECP has the total success probability approaching to the limit in theory. The present ECP has the advantage of a high success probability. Moreover, the present ECP requires only the $N$-photon system itself and some ancillary single photons, not two copies of the systems, which decreases the difficulty of its implementation largely in experiment. It maybe have good applications in quantum communication in future.Comment: 7 pages, 3 figure

Gold-Catalyzed Tandem Cycloisomerizationand Dimerization of Chiral Homopropargyl Sulfonamides

We are grateful for the financial support from the National Natural Science Foundation of China (No. 21102119 and 21272191), the Natural Science Foundation of Fujian Province of China (No. 2012J01051), NFFTBS (No. J1210014), and PCSIRT. We also thank Professor Dr. Liming Zhang (University of California Santa Barbara) for the helpful discussions

Effects of 3-Phenyl-Propenal on the Expression of Toll-Like Receptors and Downstream Signaling Components on Raw264.7 Murine Macrophages

Abstract: 3-phenyl-propenal is one of the principle compounds isolated from Guizhi (Ramulus Cinnamomi), the principal drug in Guizhi-Tang (GZT), a famous traditional Chinese medical formula. The aim of the present study was to investigate the effects of 3-phenyl-propenal on the expression of toll-like receptor 3 (TLR3), TLR4 and the downstream signaling components on Raw264.7 murine microphages. Raw264.7 cells were cultured in RPMI-1640 medium containing LPS (lipopolysaccharide) or poly (I:C) in the presence or absence of 3-phenyl-propenal. After 24-hour incubation, the medium was collected and the amount of TNF-α and IFN-β was measured by ELISA. mRNA expression of TLR3, TLR4, myeloid differentiation factor (MyD88), TRAF-6 (tumor necrosis factor receptor-associated), TRAM (toll-like receptor-associated molecule) and TRIF (TIR domain-containing adaptor inducing IFN-β) were analyzed by real-time PCR with SYBR green dye. Protein expression of TLR3 and TLR4 was analyzed by Western blotting and that of MyD88 and TRAF-6 was analyzed by immunofluorescence assay. The results indicate that LPS increased the expression of TLR4, MyD88, TRAF-6, TRAM and TRIF, but had no influence on TLR3, while poly (I:C) up-regulated the expression of TLR3, MyD88, TRAM and TRIF. 3-phenyl-propenal significantly decreased the expression of LPS-induced TLR4, MyD88, TRAF-6, while possessing no effect on LPS-induced TRAM and TRIF expression in Raw264.7 cells. When cells were stimulated by poly (I:C), 3-phenyl-propenal significantly decreased TLR3 and MyD88 expression. In conclusion, 3-phenyl-propenal blocked the over-expression of TLR3, TLR4, their downstream signaling components MyD88 and TRAF-6, which indicate that it had an antagonistic effect on TLR3 and TLR4

The imaginary part of the gap function in color superconductivity

We clarify general properties of the energy gap regarding its functional dependence on the energy-momentum dictated by the invariance under a space inversion or a time reversal. Then we derive perturbatively the equation of the imaginary part of the gap function for dense QCD in weak coupling and generalize our results from 2SC case to CFL case. We confirm that the imaginary part is down by $g$ relative to the real part in weak coupling. The numerical results show that, up to the leading order, the imaginary part is no larger than one MeV at extremely large densities and can be as large as several MeV the densities are of physical interest.Comment: 15 pages, 2 figures, typos corrected, a figure replaced. The version to be appeared in Nucl.Phys.

The momentum analyticity of two-point correlators from perturbation theory and AdS/CFT

The momentum plane analyticity of two point function of a relativistic thermal field theory at zero chemical potential is explored. A general principle regarding the location of the singularities is extracted. In the case of the N=4 supersymmetric Yang-Mills theory at large $N_c$, a qualitative change in the nature of the singularity (branch points versus simple poles) from the weak coupling regime to the strong coupling regime is observed with the aid of the AdS/CFT correspondence.Comment: 18 pages, 3 figures, typos fixed, 1 figure update