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Double-ended airfoils with round leading and trailing edges outperform conventional round-nose and sharp trailing-edge airfoils when used for the inboard part of a rigid coaxial rotor operating in forward flight, as reverse flow can occupy 80% surface of the retreating blade. However, aerodynamic design optimization for this kind of airfoils is challenging, since it is required to achieve drag reduction over a wider lift range in both forward and reverse flows but there is no method available currently. To address this problem, this article proposes an efficient hybrid inverse/optimization design method that combines inverse design and direct optimization within a surrogate-based optimization (SBO) framework. The weighted objective function consists of two components: prescribed pressure distributions and total drag. The resulting constrained optimization problem is solved by using kriging surrogate model and dedicated infill-sampling method. The proposed method is demonstrated by aerodynamic shape optimizations of a DBLN-526 airfoil and an elliptical airfoil and compared with direct optimization method. For DBLN-526 airfoil case, 7%–30% drag reduction is achieved in the range from zero lift to maximum lift and the optimum airfoil features better stall characteristics. For the case of elliptical airfoil of 40% thickness, significant drag reduction is achieved in both forward and reverse flows and the optimum airfoil features more robust aerodynamic performance at off-design Mach numbers. The results confirm that the proposed method outperforms the conventional direct optimization method and more practical for aerodynamic shape optimization of double-ended airfoils.

The aim of the present study was to investigate the clinical benefit and side effects of propranolol treatment in 106 children with infantile hemangiomas (IHs). A retrospective chart review was conducted on all children who attended the clinic between September 16, 2009 and November 11, 2013. Propranolol was administered in a progressive schedule reaching 1.0-1.5 mg/kg/day, divided into three doses. Demographic data, clinical features, imaging, treatment regimens and outcomes were investigated. Any adverse effects following medication were evaluated and managed accordingly. Preliminary analysis of the data showed the inclusion of 106 children (71 female and 35 male) with a mean age and weight at onset of treatment of 5.1 months and 7.3 kg, respectively. All 106 patients responded positively to treatment. Side effects that required intervention and/or close monitoring included diarrhea (n=10), hypotension (n=7), nightmares (n=2), agitation (n=1) and cold extremities (n=1). No long-term adverse effects were observed in any of the patients. In conclusion, propranolol administered orally at 1.0-1.5 mg/kg/day had a rapid therapeutic effect for resolving IHs with few complications.

Fresh-cut Chinese water chestnuts (CWC) turn yellow after being peeled, reducing their shelf life and commercial value. Metabolomics, the systematic study of the full complement of small molecular metabolites, was useful for clarifying the mechanism of fresh-cut CWC etiolation and developing methods to inhibit yellowing. In this study, metabolic alterations associated with etiolation at different growth stages (0 day, 2 days, 3 days, 4 days, 5 days) from fresh-cut CWC were investigated using LC–MS and analyzed by pattern recognition methods (principal component analysis (PCA), partial least squares-discriminant analysis (PLS-DA), and orthogonal projection to latent structures-discriminant analysis (OPLS-DA)). The metabolic pathways of the etiolation molecules were elucidated. The main metabolic pathway appears to be the conversion of phenylalanine to p-coumaroyl-CoA, followed by conversion to naringenin chalcone, to naringenin, and naringenin then following different pathways. Firstly, it can transform into apigenin and its derivatives; secondly, it can produce eriodictyol and its derivatives; and thirdly it can produce dihydrokaempferol, quercetin, and myricetin. The eriodictyol can be further transformed to luteolin, cyanidin, dihydroquercetin, dihydrotricetin, and others. This is the first reported use of metabolomics to study the metabolic pathways of the etiolation of fresh-cut CWC.

The non-line-of-sight visible light communications (VLC) is investigated via both the integrating sphere model and the cuboid model, which can significantly improve the VLC mobility. The influences of geometric configurations of the LED light source on the received signal intensity and corresponding impulse broadening are analyzed via ray-tracing Monte Carlo simulations. The present task may be useful for building the future's unified testing criteria of the LED light sources both in visible light communications and general indoor lighting.

The Wehrl classical information entropy of random phase negative binomial states (RPNBS) is investigated, and their Wigner function evolution in the thermal environment is also discussed. It is shown that the evolution of the RPNBS in the thermal channel can be roughly regarded as the shift of the parameters ε and α0 of the RPNBS.

The stationary entanglement and Bell violation of two qubits collectively interacting with a common thermal reservoir is investigated, and the analytical relations among average thermal photon number of the reservoir, entanglement and Bell violation of two qubits are given in detail. The initial fraction of Bell singlet state determines whether the common thermal reservoir can enhance the entanglement of two qubits or not in this case. Moreover, the stationary maximally entangled mixed state can emerge in the collective decay of two qubits in a thermal reservoir at zero-temperature only if the fraction of Bell singlet state in the initial state is not smaller than 2/3. Furthermore, it is shown that the collective decay can induce the entanglement of two qutrits initially in the maximally mixed state, and induce distillable entanglement from bound entangled states.

We investigate the concurrence and Bell violation of the standard Werner state or Werner-like states in the presence of collective dephasing. It is shown that the standard Werner state and certain kinds of Werner-like states are robust against the collective dephasing, and some kinds of Werner-like states is fragile and becomes completely disentangled in a finite-time. The threshold time of complete disentanglement of the fragile Werner-like states is given. The influence of external driving field on the finite-time disentanglement of the standard Werner state or Werner-like states is discussed. Furthermore, we present a simple method to control the stationary state entanglement and Bell violation of two qubits. Finally, we show that the theoretical calculations of fidelity based on the initial Werner state assumption well agree with previous experimental results., 7 pages, 6 figures, 1 table, RevTex4, Accepted by EPJ D

We investigate the mutual information and entanglement of stationary state of two locally driven qubits under the influence of collective dephasing. It is shown that both the mutual information and the entanglement of two qubits in the stationary state exhibit damped oscillation with the scaled action time $\gamma{T}$ of the local external driving field. It means that we can control both the entanglement and total correlation of the stationary state of two qubits by adjusting the action time of the driving field. We also consider the influence of collective dephasing on entanglement of two qutrits and obtain the sufficient condition that the stationary state is entangled., Comment: 5 pages, 2 figures, RevTex4

We investigate a possible scheme for entangling two mode thermal fields through the quantum erasing process, in which an atom is coupled with two mode fields via the interaction governed by the two-mode two-photon Jaynes-Cummings model. The influence of phase decoherence on the entanglement of two mode fields is discussed. It is found that quantum erasing process can transfer part of entanglement between the atom and fields to two mode fields initially in the thermal states. The entanglement achieved by fields heavily depends on their initial temperature and the detuning. The entanglement of stationary state is also investigated., 11 pages, 6 figures, a minor mistake is corrected

We investigate a three-qubit Heisenberg XY chain with magnetic impurity in the model of Milburn's intrinsic decoherence and the pairwise entanglement is calculated by making use of the concurrence. It is shown that the nearest neighbor pairwise entanglement rapidly decay due to intrinsic decoherence, but next to nearest neighbor qubits finally stay in a entangled stationary state in the case without the magnetic impurity. The magnetic impurity in the central qubit can protect the nearest neighbor pairwise entanglement from being completely destroyed by the intrinsic decoherence.

We investigate the entanglement of pair coherent states in the phase damping channel by adopting the relative entropy of entanglement and propose a protocol of teleportation via pair coherent states. The fidelity of the protocol is then analyzed and the influence of phase damping on the teleportation fidelity examined.

We investigate the stationary state entanglement in the interacting system of a single mode thermal field and a single qubit with phase decoherence. The influence of initial temperature of thermal field, initial mixedness of the qubit and detuning on the stationary state entanglement is then examined.

We investigate the entanglement of multi-qubits quantum Heisenberg XY chain with phase decoherence by employing the concurrence. It is shown that the nearest neighbour pairwise entanglement of XY ring with odd number length is more robust against phase decoherence than the one with even number length.

We study the entanglement of entangled coherent states in vacuum environment by employing the entanglement of formation and propose a scheme to probabilistically teleport a coherent superposition state via entangled coherent states. The mean fidelity of the scheme is then investigated and the optimal amplitude of the teleported state found.

Exercise in cold environments can cause significant metabolic regulation and antioxidant behavior. For discussing enzymatic responses towards cold adaptation, we investigated enzyme activities of adenylate cyclase (AC) and phosphodiesterase (PDE) in liver, skeletal muscle, and brown adipose tissue (BAT), as well as Na(+)·K(+) ATPase and Na(+)/K(+) ratio in blood. Malondialdehyde (MDA) and superoxide dismutase (SOD) activity in blood were also studied to address the effect of cold adaptation on oxidative damage and antioxidant system. Experimental results indicated that enzyme activities in liver, skeletal muscle and BAT maintained relatively constant for the control group. For the cold adaptation group, enzyme activities in liver and skeletal muscle were in high levels at the beginning, and then gradually decreased to similar values with the control group. However, enzyme activities in BAT performed an increasing trend and significantly higher than the control at the end. In addition, decreased oxidative damage and activated antioxidant system was observed along with the cold adaptation process.

To study the optimum enzyme extraction process of total flavonoids from Cryptotaenia japonica.The process was optimized by single factor experiments and orthogonal, the yield of total flavonoids was used as index.The optimum extraction technology was as follows: enzyme dosage: 1U/mL, pH value: 6.0, enzymatic hydrolysis temperature: 60%, enzymatic hydrolysis time: 1 h, the rate of material to liquid: 1 : 30, extraction temperature: 70 degrees C, extraction time: 1 h, the average extraction rate of total flavonoids from Cryptotaenia japonica was 4.76%.The method is an effective way to extract total flavonoids from Cryptotaenia japonica with high extract rate.

The time evolution of the general driven time-dependent harmonic oscillator is studied and the propagator and wave function are obtained by using a generalized canonical transformation and path integral method. We then proceed to construct the squeezed states for the system by making use of the wave function. The damped driven harmonic oscillator and the harmonic oscillator with strongly pulsating mass under the action of an arbitrary driving force are discussed as illustrative examples.

This paper analyzed the insufficient of traditional clustering methods using in complex formula for multidimensional clustering. A definition of ELD distance has been given based on the analysis of the specific characteristics of complex prescription and the results of traditional clustering algorithm. A algorithm named NNELAF has been proposed to solve the problem, and the test result showed that this algorithm could cluster the energy formulation more consistency with expert judgment.

A simulation scheme of quantum version of Cournot's Duopoly is proposed, in which there is a new Nash equilibrium that may be also Pareto optimal without any entanglement involved. The unique property of this simulation scheme is decoherence-free against the symmetric photon loss. Furthermore, we analyze the effects of the asymmetric information on this simulation scheme and investigate the case of asymmetric game caused by asymmetric photon loss. A second-order phase transition-like behavior of the average profits of the firm 1 and firm 2 in Nash equilibrium can be observed with the change of the degree of asymmetry of the information or the degree of "virtual cooperation". It is also found that asymmetric photon loss in this simulation scheme plays a similar role with the asymmetric entangled states in the quantum game. PACS numbers: 02.50.Le, 03.67.-a, Comment: 7 pages, 4 figures, RevTex, some contents have been revised

The mean parity (the Wigner function at the origin) of excited binomial states, excited coherent states and excited thermal states in thermal channel is investigated in details. It is found that the single-photon excited binomial state and the single-photon excited coherent state exhibit certain similarity in the aspect of their mean parity in the thermal channel. We show the negative mean parity can be regarded as an indicator of nonclassicality of single-photon excitation of optical fields with a little coherence, especially for the single-photon excited thermal states., 4 pages, 4 figures, RevTex4; PACS numbers: 42.50.Dv, 03.65.Yz, 05.40.Ca; Three typo errors have been corrected

The nonclassicality of single photon-added thermal states in the thermal channel is investigated by exploring the volume of the negative part of the Wigner function. The Wigner functions become positive when the decay time exceeds a threshold value $\gamma{t}_c$, which only depends on the effective temperature or mean thermal photon number of the thermal channel, but not depends on the effective temperature of the initial thermal state. This phenomenon is similar with the case of single quantum excitation of classical coherent states in thermal channel. Furthermore, we firstly demonstrate $\gamma{t}_c$ is the same for arbitrary pure or mixed nonclassical optical fields with zero population in vacuum state. PACS numbers: 42.50.Dv, 03.65.Yz, 05.40.Ca, Comment: 4 pages, 2 figures, revtex4, Welcome any comments

We investigate the economical Gaussian cloning of coherent states with the known phase, which produces $M$ copies from $N$ input replica and can be implemented with degenerate parametric amplifiers and beam splitters.The achievable fidelity of single copy is given by $2M\sqrt{N}∕[\sqrt{N}(M\ensuremath{-}1)+\sqrt{(1+N)({M}^{2}+N)}]$, which is bigger than the optimal fidelity of the universal Gaussian cloning. The cloning machine presented here works without ancillary optical modes and can be regarded as the continuous variable generalization of the economical cloning machine for qudits.

We propose a scheme for realizing a two-qubit quantum phase gate between atoms inside a high-Q optical cavity. In the scheme, the dispersive interaction between atoms and the cavity field induces photon-number Stark shift, which can yield a resonant interaction inside one selected atom-field subspace and leave the others in a highly dispersive regime. Due to the selective atom-cavity interaction, (1) the scheme only requires commonly addressing the atoms inside the optical cavity during the gate operation, and (2) it can be directly used to implement an N-qubit conditional phase gate. These properties can significantly reduce the number of operations for implementing quantum computation and quantum algorithms.

We investigate the nonclassicality of photon-added coherent states in the photon loss channel by exploring the entanglement potential and negative Wigner distribution. The total negative probability defined by the absolute value of the integral of the Wigner function over the negative distribution region reduces with the increase of decay time. The total negative probability and the entanglement potential of pure photon-added coherent states exhibit the similar dependence on the beam intensity. The reduce of the total negative probability is consistent with the behavior of entanglement potential for the dissipative single-photon-added coherent state at short decay times., 5 pages, 5 figures, RevTex4, submitted

The nonclassicality of photon-added coherent fields in the thermal channel is investigated by exploring the volume of the negative part of the Wigner function which reduces with the dissipative time. The Wigner functions become positive when the decay time exceeds a threshold value. For the case of the single photon-added coherent state, we derive the exact threshold values of decay time in the thermal channel. For arbitrary partial negative Wigner distribution function, a generic analytical relation between the mean photon number of heat bath and the threshold value of decay time is presented. Finally, the possible application of SPACSs in quantum computation has been briefly discussed. OCIS codes: 270.0270, 270.2500, 000.5490, 10 pages, 5 figures, three references are added, and a brief discussion of the possible applications of SPACSs in quantum information processes has been added; Accepted by JOSA B

The study was to evaluate the microscopic changes on skin and soft tissue after repeated expansion for clinical work.Six little pigs were divideded as: conventional expansion group, repeated expansion group, and blank control group. Histologic, ultrastructure and bFGF of the skin were observed and measured in each group after samples had been made.The skin and soft tissue after repeated expansion were healthy on the whole. Compared with the conventional expansion group, there was more microscopic change in the repeated expansion group. Collagen fibers were injured evidently. Cells were injured slightly and proliferated much more, and moreover, they were more activated. The content of bFGF was more higher.The skin and soft tissue after repeated expansion are healthy on the whole by more growth and more repair though repeated expansion may result in more injuries. So repeated expansion is safe and feasible.

In this report, the performance analysis of 10Gbps optical receiver for fiber optical link is presented. Non-Return to Zero (NRZ) electrical signals from a Pseudo-Random Bit Sequence (PRBS) Generator are used as modulation input. Signals in the optical domain are detected at the PIN photodiode (PIN-PD) and are converted into electrical output signals. These electrical signals are filtered through a low pass bessel filter. Effects of bandwidth and thermal noise of receiver on the link performance are studied in detail. For the 10Gbps fiber optical communication, a Q factor of 6.55 and the BER of 5.23E?11 are observed for the worstcase, when the receiver is operated at 100°C. it is shown that BER heavily depends on thermal noise. The relation between the receiver sensitivity and the thermal noise is also investigated.

A scheme for generating the maximally entangled mixed state of two atoms on-resonance asymmetrically coupled to a single mode optical cavity field is presented. The part frontier of both maximally entangled mixed states and maximal Bell violating mixed states can be approximately reached by the evolving reduced density matrix of two atoms if the ratio of coupling strengths of two atoms is appropriately controlled. It is also shown that exchange symmetry of global maximal concurrence is broken if and only if coupling strength ratio lies between $\frac{\sqrt{3}}{3}$ and $\sqrt{3}$ for the case of one-particle excitation and asymmetric coupling, while this partial symmetry-breaking can not be verified by detecting maximal Bell violation., Comment: 5 pages, 5 figures

The simple system of two atoms couple to single mode optical cavity with the phase decoherence is studied for investigating the entanglement and Bell violation between atoms and cavity or between two atoms. We show that in the resonance case (i) atom-field entanglement rapidly decays with phase decoherence and disappears in the stationary state, (ii) atom-atom entanglement is more robust against phase decoherence and survives in the stationary state. In the nonresonance case, the pairwise atom-atom and atom-field entanglement is sensitive to the detuning parameter and is not completely destroyed during evolution. On the other hand, violation of Bell-CHSH inequality is very fragile against the phase decoherence and finally disappears in the stationary state. The phenomenon that the more Bell violation, the less entanglement, or vice versa in such a realistic physical system, is revealed. This phenomenon maybe is the consequence of the choice of concurrence as the entanglement measure and the observables to build the Bell-CHSH inequality. The genuine three-partite entanglement is also analyzed by making use of the state preparation fidelity. It is shown that the genuine three-partite entanglement can appear in the evolution of the system even in the presence of the phase decoherence.

The ground entanglement and thermal entanglement in quantum mixed spin chains consisting of two integer spins 1 and two half integer spins 1/2 arrayed as ${1/2}-{1/2}-1-1$ in a unit cell with antiferromagnetic nearest-neighbor couplings $J_1$($J_2$) between the spins of equal (different) magnitudes, are investigated by adopting the log-negativity. The ground entanglement transition found here is closely related with the valence bond state transition, and the thermal entanglement near the critical point is calculated and shown that two distinct behaviors exist in the nearest neighbor same kind of spins and different kind of spins, respectively. The potential application of our results on the quantum information processing is also discussed., 5 pages, 4 figures, RevTex4, A minor correction is added into the figure caption

We investigate the dynamics of a kicked particle in an infinite square well undergoing frequent measurements of energy. For a large class of periodic kicking force, constant diffusion is found in such a non-KAM system. The influence of phase shift of the kicking potential on the short-time dynamical behavior is discussed. The general asymptotical measurement-assisted diffusion rate is obtained. The entanglement between the particle and the measuring apparatus is investigated. There exist two distinct dynamical behaviors of entanglement. The bipartite entanglement grows with the kicking steps and it gains larger value for the more chaotic system. However, the pairwise entanglement between the system of interest and the partial spins of the measuring apparatus decreases with the kicking steps. The relation between the entanglement and quantum diffusion is also analyzed. PACS numbers: 05.45.Mt, 03.65.Ta, 7 pages, 5 figures, RevTex4, Accepted by Phys. Rev. E

We investigate nonclassical properties of the output of a Bose-Einstein condensate in Milburn's model of intrinsic decoherence. It is shown that the squeezing property of the atom laser is suppressed due to decoherence. Nevertheless, if some very special conditions were satisfied, the squeezing properties of atom laser could be robust against the decoherence., Comment: 17 pages, 5 figures, Latex

In some off-resonant cases, the reduced density matrix of two atoms symmetrically coupled with an optical cavity can very approximately approach to maximally entangled mixed states or maximal Bell violation mixed states in their evolution. The influence of phase decoherence on the generation of maximally entangled mixed state is also discussed. PACS numbers: 03.67.-a, 03.65.Ud, Comment: 7 pages, 4 figures, Latex, have a major revision of content

The entanglement of pair cat states in the phase damping channel is studied by employing the relative entropy of entanglement. It is shown that the pair cat states can always be distillable in the phase damping channel. Furthermore, we analyze the fidelity of teleportation for the pair cat states by using joint measurements of the photon-number sum and phase difference., Comment: 15 page, 6 figures, Latex

We study the quantum entanglement between two coupled cavities, in which one is initially prepared in a mesoscopic superposition state and the other is in the vacuum in dissipative environment and show how the entanglement between two cavities can arise in the dissipative environment. The dynamic behavior of the nonlocality for the system is also investigated., 12 pages, 5 figures