Symmetry restoration and quantumness reestablishment

A realistic quantum many-body system, characterized by a generic microscopic Hamiltonian, is accessible only through approximation methods. The mean field theories, as the simplest practices of approximation methods, commonly serve as a powerful tool, but unfortunately often violate the symmetry of the Hamiltonian. The conventional BCS theory, as an excellent mean field approach, violates the particle number conservation and completely erases quantumness characterized by concurrence and quantum discord between different modes. We restore the symmetry by using the projected BCS theory and the exact numerical solution and find that the lost quantumness is synchronously reestablished. We show that while entanglement remains unchanged with the particle numbers, quantum discord behaves as an extensive quantity with respect to the system size. Surprisingly, discord is hardly dependent on the interaction strengths. The new feature of discord offers promising applications in modern quantum technologies.Comment: 17 pages and 3 figure

Twist-3 light-cone distribution amplitudes of the scalar mesons within the QCD sum rules and their application to the B→SB \to S transition form factors

We investigate the twist-3 light-cone distribution amplitudes (LCDAs) of the scalar mesons $a_0$, $K^{\ast}_0$ and $f_0$ within the QCD sum rules. The QCD sum rules are improved by a consistent treatment of the sizable $s$-quark mass effects within the framework of the background field approach. Adopting the valence quark component $(\bar{q}_1 q_2)$ as the dominant structure of the scalar mesons, our estimation for their masses are close to the measured $a_0(1450)$, $K^{\ast}_0(1430)$ and $f_0(1710)$. From the sum rules, we obtain the first two non-zero moments of the twist-3 LCDAs $\phi^{s,\sigma}_{a_0}$: $\langle \xi_{s,a_0}^{2(4)} \rangle=0.369 \;(0.245)$ and $\langle \xi_{\sigma,a_0}^{2(4)} \rangle=0.203 \;(0.093)$; those of the twist-3 LCDAs $\phi_{K^*_0}^{s,\sigma}$: $\langle \xi_{s,K^{\ast}_0}^{1(2)} \rangle =0.004\;(0.355)$ and $\langle \xi_{\sigma,K^{\ast}_0}^{1(2)} \rangle =0.018\;(0.207)$; and those of the twist-3 LCDAs $\phi_{f_0}^{s,\sigma}$: $\langle \xi_{s,f_0}^{2(4)} \rangle=0.335 \;(0.212)$ and $\langle \xi_{\sigma,f_0}^{2(4)} \rangle=0.196 \; (0.088)$, respectively. As an application of those twist-3 LCDAs, we study the $B \to S$ transition form factors by introducing proper chiral currents into the correlator, which is constructed such that the twist-3 LCDAs give dominant contribution and the twist-2 LCDAs make negligible contribution. Our results of the $B \to S$ transition form factors at the large recoil region $q^2 \simeq 0$ are consistent with those obtained in the literature, which inversely shows the present twist-3 LCDAs are acceptable.Comment: 14 pages, 12 figures, 7 table

Higher-order solutions to non-Markovian quantum dynamics via hierarchical functional derivative

Solving realistic quantum systems coupled to an environment is a challenging task. Here we develop a hierarchical functional derivative (HFD) approach for efficiently solving the non-Markovian quantum trajectories of an open quantum system embedded in a bosonic bath. An explicit expression for arbitrary order HFD equation is derived systematically. Moreover, it is found that for an analytically solvable model, this hierarchical equation naturally terminates at a given order and thus becomes exactly solvable. This HFD approach provides a systematic method to study the non-Markovian quantum dynamics of an open system coupled to a bosonic environment.Comment: 5 pages, 2 figure

A Novel Rough Set Model in Generalized Single Valued Neutrosophic Approximation Spaces and Its Application

In this paper, we extend the rough set model on two different universes in intuitionistic fuzzy approximation spaces to a single-valued neutrosophic environment

2,4-Dichloro-6-nitro­benzoic acid

The title compound, C7H3Cl2NO4, was prepared by the reaction of 2,4-dichloro-6-nitro­toluene with 20% HNO3 solution at 430 K. The carboxyl and nitro groups are twisted by 82.82 (12) and 11.9 (2)°, respectively, with respect to the benzene ring. The crystal structure is stabilized by O—H⋯O hydrogen bonding between carboxyl groups and weak C—H⋯O hydrogen bonding between the nitro group and the benzene ring of an adjacent mol­ecule

Dynamical invariants in non-Markovian quantum state diffusion equation

We find dynamical invariants for open quantum systems described by the non-Markovian quantum state diffusion (QSD) equation. In stark contrast to closed systems where the dynamical invariant can be identical to the system density operator, these dynamical invariants no longer share the equation of motion for the density operator. Moreover, the invariants obtained with from bi-orthonormal basis can be used to render an exact solution to the QSD equation and the corresponding non-Markovian dynamics without using master equations or numerical simulations. Significantly we show that we can apply these dynamic invariants to reverse-engineering a Hamiltonian that is capable of driving the system to the target state, providing a novel way to design control strategy for open quantum systems.Comment: 6 pages, 2 figure

Cardioprotective effects of the total flavonoids of Polygonum cuspidatum Sieb. et Zucc. Root extract on experimental myocardial infarction in mice

Purpose: To study the cardioprotective effects of the total flavonoids from the roots of Polygonum cuspidatum Sieb. et Zucc. (FHZ) on experimental myocardial infarction in mice.Methods: Ultrasonic-assisted extraction of FHZ was optimized by response surface methodology (RSM) to obtain a higher extraction yield. Myocardial infarction (MI) was established by ligation of the left anterior descending (LAD) branch of the coronary artery in mice. Cardiac troponin T (cTnT), creatine phosphokinase (CPK), lactate dehydrogenase (LDH), lipid peroxide (LPO), malondialdehyde (MDA) and superoxide dismutase (SOD) levels in the serum of mice were assessed by enzyme-linked immunosorbent assay. Furthermore, myocardial infarction size (MIS) was examined by Masson’s Trichrome staining on heart tissues.Results: Optimum extraction conditions of FHZ were as follows: an ethanol concentration of 69.03 %, a liquid-solid ratio of 27.14 g/mL and an extraction time of 30.30 min. The obtained extraction conditions were proven to be accurate and reliable. After treatment with FHZ for 3 and 7 days, the serum level of cTnT in MI mice decreased significantly. Also, the serum levels of CPK, LPO, MDA, and LDH were significantly decreased while SOD level increased in MI mice treated with FHZ. Furthermore, after treatment with FHZ for two weeks, the MIS of MI mice decreased (p < 0.01).Conclusion: RSM is a useful tool to optimize the ultrasonic-assisted extraction conditions for FHZ. Furthermore, FHZ possesses significant cardioprotective effects on experimental myocardial infarction in mice and thus may find application in the clinical management of myocardial infarction.Keywords: Polygonum cuspidatum, Flavonoids, Response surface methodology, Myocardial infarction, Cardioprotectiv

Trajectory tracking and traction coordinating controller design for lunar rover based on dynamics and kinematics analysis

Trajectory tracking control is a necessary part for autonomous navigation of planetary rover and traction coordinating control can reduce the forces consumption during navigation. As a result, a trajectory tracking and traction coordinating controller for wheeled lunar rover with Rocker Bogie is proposed in the paper. Firstly, the longitudinal dynamics model and the kinematics model of six-wheeled rover are established. Secondly, the traction coordinating control algorithm is studied based on sliding mode theory with improved exponential approach law. Thirdly, based on kinematics analysis and traction system identification, the trajectory tracking controller is designed using optimal theory. Then, co-simulations between ADAMS and MATLAB/Simulink are carried out to validate the proposed algorithm, and the simulation results have confirmed the effectiveness of path tracking and traction mobility improving