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The total correlations in a bipartite quantum system are measured by the quantum mutual information $\mathcal{I}$, which consists of quantum discord and classical correlation. However, recent results in quantum information shows that coherence, which is a part of total correlation, is more general and more fundamental than discord. The role of coherence in quantum resource theories is worthwhile to investigate. We first study the relation between quantum discord and coherence by reducing the difference between them. And then, we consider the dynamics of quantum discord, classical correlations and quantum coherence under incoherent quantum channels. We discover that coherence indicate the behavior of quantum discord (classical correlation) for times $t\bar t$. What is more, the coherence frozen and decay indicate the quantum discord and classical correlation frozen and decay respectively., Comment: 7pages, 5figures

We study superregular (SR) breathers (i.e., the quasi-Akhmediev breather collision with a certain phase shift) in a complex modified Korteweg-de Vries equation. We demonstrate that such SR waves can exhibit intriguing nonlinear structures, including the half-transition and full-suppression modes, which have no analogues in the standard nonlinear Schrodinger equation. In contrast to the standard SR breather formed by pairs of quasi-Akhmediev breathers, the half-transition mode describes a mix of quasi-Akhmediev and quasi-periodic waves, whereas the full-suppression mode shows a non-amplifying nonlinear dynamics of localized small perturbations associated with the vanishing growth rate of modulation instability. Interestingly, we show analytically and numerically that these different SR modes can be evolved from an identical localized small perturbation. In particular, our results demonstrate an excellent compatibility relation between SR modes and the linear stability analysis.

We investigate linear interference effects between a nonlinear plane wave and bright solitons, which are admitted by pair-transition coupled two-component Bose-Einstein condensate. We demonstrate the interference effects can induce several localized waves possessing distinctive wave structures, mainly including anti-dark soliton, W-shaped soliton, multi-peak soliton, Kuznetsov-Ma like breather, and multi-peak breather. Especially, the explicit conditions for them are clarified by a phase diagram based on the linear interference properties. Furthermore, the interactions between these localized waves are discussed. The detailed analysis indicate that soliton-soliton interaction induced phase shift brings the collision between these localized waves be inelastic for soliton involving collision, and be elastic for breathers. These characters come from that the profile of solitons depend on relative phase between bright soliton and plane wave, and the profile of breathers do not depend on the relative phase. These results would motivate more discussions on linear interference between other nonlinear waves. Especially, the solitons or breathers obtained here are not related with modulational instability. The underlying reasons are discussed in detail., 8 pages, 7 figures

To investigate the efficacy, advantages and disadvantages of internal and external elbow joint approach and olecranon osteotomy approach for the treatment of intercondylar fracture of humerus.From October 2012 to May 2016, 18 cases of intercondylar fracture of humerus were treated by operation including 12 males and 6 females with a mean age of 33.5 years old (ranged from 4 to 56 years old); 8 cases were operated by internal and external elbow joint approach, 10 cases were operated by olecranon osteotomy approach. According to AO classification, 3 cases were type C1, 8 cases were type C2, 7 cases were type C3. All patients were excluded from neurologic and vascular injuries.All patients were followed up from 12 to 26 months with an average of 15 months. The incision healed well and no heterotopic ossification was found. According to the modified Cassebaum elbow function score, the result was excellence in 14 cases, good in 3 cases, fair in 1 case.According to the fracture type, the appropriate surgical approach and fixation were selected in order to get anatomic reduction. Rigid fixation, and early functional exercise is important condition for successful operation and satisfactory functional recovery in intercondylar fracture of the humerus.

Einstein-Podolsky-Rosen (EPR) steering is an intermediate type of quantum nonlocality which sits between entanglement and Bell nonlocality. A set of correlations is Bell nonlocal if it does not admit a local hidden variable (LHV) model, while it is EPR nonlocal if it does not admit a local hidden variable-local hidden state (LHV-LHS) model. It is interesting to know what states can generate EPR-nonlocal correlations in the simplest nontrivial scenario, that is, two projective measurements for each party sharing a two-qubit state. Here we show that a two-qubit state can generate EPR-nonlocal full correlations (excluding marginal statistics) in this scenario if and only if it can generate Bell-nonlocal correlations. If full statistics (including marginal statistics) is taken into account, surprisingly, the same scenario can manifest the simplest one-way steering and the strongest hierarchy between steering and Bell nonlocality. To illustrate these intriguing phenomena in simple setups, several concrete examples are discussed in detail, which facilitates experimental demonstration. In the course of study, we introduce the concept of restricted LHS models and thereby derive a necessary and sufficient semidefinite-programming criterion to determine the steerability of any bipartite state under given measurements. Analytical criteria are further derived in several scenarios of strong theoretical and experimental interest., Comment: New results added, 13 pages, 3 figures; published in Phys. Rev. A

The periodic $Z_n$-Belavin model on a lattice with an arbitrary number of sites $N$ is studied via the off-diagonal Bethe Ansatz method (ODBA). The eigenvalues of the corresponding transfer matrix are given in terms of an unified inhomogeneous $T-Q$ relation. In the special case of $N=nl$ with $l$ being also a positive integer, the resulting $T-Q$ relation recovers the homogeneous one previously obtained via algebraic Bethe Ansatz., 24pages, no figures

Two-qubit Bell-diagonal states can be depicted as a tetrahedron in three dimensions. We investigate the structure of quantum resources, including coherence and quantum discord, in the tetrahedron. The ordering of different resources measures is a common problem in resource theories, and which measure should be chosen to investigate the structure of resources is still an open question. We consider the structure of quantum resources which is not affected by the choice of measure. Our work provides a complete structure of coherence and quantum discord for Bell-diagonal states. The pictorial approach also indicates how to explore the structure of resources even when we don't have consistent measure of a concrete quantum resource., 6 pages, 5 figures

We investigate the role of quantum coherence depletion (QCD) in Grover search algorithm (GA) by using several typical measures of quantum coherence and quantum correlations. By using the relative entropy of coherence measure ($\mathcal{C}_r$), we show that the success probability depends on the QCD. The same phenomenon is also found by using the $l_1$ norm of coherence measure ($\mathcal{C}_{l_1}$). In the limit case, the cost performance is defined to characterize the behavior about QCD in enhancing the success probability of GA, which is only related to the number of searcher items and the scale of database, no matter using $\mathcal{C}_r$ or $\mathcal{C}_{l_1}$. In generalized Grover search algorithm (GGA), the QCD for a class of states increases with the required optimal measurement time. In comparison, the quantification of other quantum correlations in GA, such as pairwise entanglement, multipartite entanglement, pairwise discord and genuine multipartite discord, cannot be directly related to the success probability or the optimal measurement time. Additionally, we do not detect pairwise nonlocality or genuine tripartite nonlocality in GA since Clauser-Horne-Shimony-Holt inequality and Svetlichny's inequality are not violated., 9 pages, 5 figures

Lycium barbarum polysaccharides (LBP) have been reported to have a wide range of beneficial effects including neuroprotection, anti-aging and anticancer. However, the anti-inflammation mechanism of LBP on primary cultured rat hippocampal neurons injured by oxygen-glucose deprivation/reperfusion (OGD/RP) is incompletely understood. We investigate the neuroprotective effects of LBP on neonatal rat primary cultured hippocampal neurons injured by OGD/RP with different approaches: MTT assay was used to detect cell viability, lactate dehydrogenase leakage was used to detect neuronal damage, formation of reactive oxygen species was determined by using fluorescent probe DCFH-DA. Hoechst 33,342 staining and TUNEL staining were used to determine the cell apoptosis. JC-1 was used to evaluate loss of mitochondrial membrane potential (MMP). The fluorescence intensity of [Ca2+]i in hippocampal neurons was determined by laser scanning confocal microscopy. The expression of various apoptotic markers such as TLR4, IκB, IL-6 and NF-κB were investigated by RT-PCR and western blot analysis. Results from each approach demonstrated that LBP increased the cell abilities and decreased the cell morphologic impairment. Furthermore, LBP increased MMP but inhibited [Ca2+]i elevation and significantly suppressed overexpression of NF-κB, IL-6 TLR4 and increased IκB expression.

We study breathers and solitons on different backgrounds in optical fiber system, which is governed by generalized coupled Hirota equations with four wave mixing effect. On plane wave background, a transformation between different types of solitons is discovered. Then, on periodic wave background, we find breather-like nonlinear localized waves of which formation mechanism are related to the energy conversion between two components. The energy conversion results from four wave mixing. Furthermore, we prove that this energy conversion is controlled by amplitude and period of backgrounds. Finally, solitons on periodic wave background are also exhibited. These results would enrich our knowledge of nonlinear localized waves' excitation in coupled system with four wave mixing effect.

We study rogue wave excitation pattern in a two-component Bose-Einstein condensate with pair-transition effects. The results indicate that rogue wave excitation can exist on a stripe phase background for which there are cosine and sine wave background in the two components respectively. The rogue wave peak can be much lower than the ones of scalar matter wave rogue waves, and varies with the wave period changing. Both rogue wave pattern and rogue wave number on temporal-spatial plane are much more abundant than the ones reported before. Furthermore, we prove that the rogue wave number can be $n (n+1)/2+m (m+1)/2$ (where $m,n $ are arbitrary non-negative integers), in contrast to $n(n+1)/2$ for scalar nonlinear Schr\"{o}dinger equation described systems. These results would enrich our knowledge on nonlinear excitations in multi-component Bose-Einstein condensate with transition coupling effects., Comment: 8 pages, 8 figures

We analytically study optical rogue waves in the presence of quintic nonlinearity and nonlinear dispersion effects. Dynamics of the rogue waves are investigated through the precise expressions of their peak, valley, trajectory, and width. Based on this, the properties of a few specific rogue waves are demonstrated in detail, and the dynamical evolution of rogue waves can be well controlled under different nonlinearity management. It shows that the peak reaches its maximum and the valley becomes minimized when the width evolves to the minimum value. Moreover, we find that the higher-order effects here achieve balance due to the integrability, and they only influence the rogue waves' trajectory.

We provide a family of general monogamy inequalities for global quantum discord (GQD), which can be considered as an extension of the usual discord monogamy inequality. It can be shown that those inequalities are satisfied under the similar condition for the holding of usual monogamy relation. We find that there is an intrinsic connection among them. Furthermore, we present a different type of monogamy inequality and prove that it holds under the condition that the bipartite GQDs do not increase when tracing out some subsystems. We also study the residual GQD based on the second type of monogamy inequality. As applications of those quantities, we investigate the GQDs and residual GQD in characterizing the quantum phase transition in the transverse field Ising model., 11 pages, 6 figures

The spin-1/2 XYZ model with both periodic and anti-periodic boundary conditions is studied via the off-diagonal Bethe ansatz method. The exact spectra of the Hamiltonians and the Bethe ansatz equations are derived by constructing the inhomogeneous T-Q relations, which allow us to treat both the even N (the number of lattice sites) and odd N cases simultaneously in an unified approach., Comment: 20 pages, 3 tables, published version, numerical check is added

After constructing the Bethe state of the XXZ Gaudin model with generic non-diagonal boundary terms, we analyze the properties of this state and obtain the determinant representations of the scalar products for this XXZ Gaudin model.

Objective To observe the differences in efficacy on treatment of fractures of the middle and lower 1/3 of the tibiofibula between cribriform splints plus electroacupuncture, warming needle and moxibustion only, and external fixation with traditional splints plus the administration of an herbal formula. Clinical efficacy and the effects on serum bone morphogenic protein −7 (BMP-7) and endothelin −1 (ET-1) were both measured. Method 600 patients with fractures of the middle and lower 1/3 of the tibiofibula were randomly divided into three groups according to andome number table: splint with electroacupuncture (group A), warm needling moxibustion group (group B) and splint with traditional Chinese medicine herb (Group C). Cribriform splints with electroacupuncture were used in group A, warming needling therapy were adopted in group B, and traditional splints with external fixation were used along with oral administration of musk bone capsules ( ) in group C. Clinical results for the three groups were compared, and ELISA method was used to detect the serum BMP-7 and ET-1 of patients in the three groups before and after treatment. Results Group A was better than group B and group C in terms of clinical healing days and delayed healing status (P Conclusion Electroacupuncture treatment with cribriform splints for fractures of the middle and lower 1/3 of the tibiofibula resulted in significantly shorter clinical healing time, and lower incidence of delayed healing compared to warm needling or splints with a traditional Chinese herbal formula. Its mechanism may be associated with greater regulation of serum BMP-7 and ET-1 through electroacupuncture.

The complicated motion of the gyroscope includes the rotation, the precession, the nutation and the sliding motion which are coupled, and it is affected by the lash-force by the whip. Taking the gyroscope which is moving stably as the research subject, according to the motion characteristics of the gyro’s rotation and precession, the gyro is assumed to be the two-force bar, and the coupled relationship of the gyroscope is analyzed quantitatively. The three-dimensional complicated motion in the different categories is analyzed. The nonlinear differential equations in the different categories is derived and linearized by the minor variables method, and then the three-dimensional motion equations on the rotation, precession, nutation and slipping of the gyroscope in the different categories is established. Take the big gym gyroscope as the example, the influence of the force, time and position of the whip on the motion state of the gyroscope is analyzed in detail, and provides the basis for the design of the gyroscope.

Yellow River Delta had been extensively engineered to control flooding and to protect coastal development which leaded to wetlands destruction and severe water pollution. The Yellow River Conservancy Commission decided the water supplement to the wetland during the water and sediment regulation period in 2010. In order to study the water quantity and distribution simulation, one-dimensional SOBEK model was used to flood simulation in the Yellow River Delta. The Re of the daily water level at four stations for the calibration period were 0.6%, 2.3%, 2.9%, 7.0%,.which indicated that the simulated values matched very well with the observed values. The SOBEK model had predicted the water level volume in 2003 within the range of acceptable accuracy. It indicated that the one-dimensional method SOBEK model was suitable for the flood simulation.

CCCTC-binding factor (CTCF), a highly conserved zinc finger protein, is a master organizer of genome spatial organization and has multiple functions in gene regulation. Mounting evidence indicates that CTCF regulates the imprinted genes Igf2 and H19 by organizing chromatin at the Igf2/H19 locus, although the mechanism by which CTCF carries out this function is not fully understood. By yeast two-hybrid screening, we identified vigilin, a multi-KH-domain protein, as a new partner of CTCF. Subsequent coimmunoprecipitation and glutathione S-transferase pulldown experiments confirmed that vigilin interacts with CTCF. Moreover, vigilin is present at several known CTCF target sites, such as the promoter regions of c-myc and BRCA1, the locus control region of β-globin, and several regions within the Igf2/H19 locus. In vivo depletion of vigilin did not affect CTCF binding; however, knockdown of CTCF reduced vigilin binding to the H19 imprinting control region. Furthermore, ectopic expression of vigilin significantly downregulated Igf2 and upregulated H19, whereas depletion of vigilin upregulated Igf2 and downregulated H19, in HepG2, CNE1 and HeLa cells. These results reveal the functional relevance of vigilin and CTCF, and show that the CTCF-vigilin complex contributes to regulation of Igf2/H19.

Vigilin contains multiple KH domains and is an evolutionarily conserved RNA-binding protein from yeast to the human. Its reported roles in human carcinogenesis are controversial in different types of human cancers. To obtain the specific expression profiles of vigilin in human hepatocellular carcinomas (HCCs), we examined vigilin protein levels in normal human liver, liver cirrhosis, adjacent non-tumor liver and HCC tumor tissues as well as in several HCC cell lines. We discovered that vigilin expression increased progressively from the liver cirrhosis tissue to adjacent non-tumor liver tissue and then to HCC tumor cells. Vigilin protein was also overexpressed in all three HCC cell lines examined, HepG2, BEL7402 and SMMC7721, when compared with the vigilin expression level in the L-02 human embryonic hepatocyte cell line. We further investigated the impact of vigilin knockdown on HCC cell proliferation, survival, motility, tumor growth and sensitivity to chemotherapy. We found that knockdown of vigilin in the BEL7402 HCC cells significantly inhibited their proliferation, colony formation and migration, but largely enhanced the cisplatin treatment-induced growth inhibition of these cells in culture. We also found that vigilin knockdown effectively inhibited the growth of BEL7402 cell-derived xenograft tumors in nude mice by decreasing the proliferation and increasing the apoptosis of the BEL7402 HCC cells. Taken together, these results suggest that progressively upregulated vigilin may serve as a molecular risk marker for HCC development, and targeting vigilin may help to inhibit HCC cell growth, survival and migration.

The one-dimensional Hubbard model with arbitrary boundary magnetic fields is solved exactly via the Bethe ansatz methods. With the coordinate Bethe ansatz in the charge sector, the second eigenvalue problem associated with the spin sector is constructed. It is shown that the second eigenvalue problem can be transformed into that of the inhomogeneous XXX spin chain with arbitrary boundary fields which can be solved via the off-diagonal Bethe ansatz method., published version, 15 pages, no figure

The $so(5)$ (i.e., $B_2$) quantum integrable spin chains with both periodic and non-diagonal boundaries are studied via the off-diagonal Bethe Ansatz method. By using the fusion technique, sufficient operator product identities (comparing to those in [1]) to determine the spectrum of the transfer matrices are derived. For the periodic case, we recover the results obtained in \cite{NYReshetikhin1}, while for the non-diagonal boundary case, a new inhomogeneous $T-Q$ relation is constructed. The present method can be directly generalized to deal with the $so(2n+1)$ (i.e., $B_n$) quantum integrable spin chains with general boundaries., Published version, 42 pages, no figure

We discover new type of interference patterns generated in the focusing nonlinear Schr\"odinger equation (NLSE) with localised periodic initial conditions. At special conditions, found in the present work, these patterns exhibit novel chess-board-like spatio-temporal structures which can be observed as the outcome of collision of two breathers. The infinitely extended chess-board-like patterns correspond to the continuous spectrum bands of the NLSE theory. More complicated patterns can be observed when the initial condition contains several localised periodic swells. These patterns can be observed in a variety of physical situations ranging from optics and hydrodynamics to Bose-Einstein condensates and plasma., Comment: 6 pages, 5 figures

The anisotropic four-component spin chain with integrable off-diagonal boundary terms is studied by the nested off-diagonal Bethe ansatz method. Based on the intrinsic properties of the associated R-matrix, the recursive operator product identities of the fused transfer matrices are obtained by using the fusion. The asymptotic behaviors and the values of fused transfer matrices at certain special points are derived explicitly. The nested inhomogeneous T − Q relations of the system are constructed, and the self-consistency of these relations is demonstrated. The method and the results can be applied to study the eigenvalue problems of multicomponent integrable models with open boundaries.

Diaokou River is one of the old courses of the Yellow River access to the sea before 1976 and its estuarine delta is an important part of National Nature Reserve of Yellow River Delta. The Yellow River Conservancy Commission decided the ecological water supplement to the wetland during the water and sediment regulation period in 2010. In this study, we analyzed the land use and land cover changes before and after the ecological water supplement in Diaokou River by using HJ-1B CCD data. The impact of the ecological water supplement on land use and land cover changes in Diaokou River was remarkable. The expansion of shrub-grassland and water body at large scale is conspicuous, while decreasing areas of shallows was 15.03 km2 and unutilized land decreasing amplitude was 28%. The main area of land use change was in Yiqianer protected areas, where concentrated in the estuary of the Diaokou River.

The anisotropic spin-1/2 chains with arbitrary boundary fields are diagonalized with the off-diagonal Bethe ansatz method. Based on the properties of the R-matrix and the K-matrices, an operator product identity of the transfer matrix is constructed at some special points of the spectral parameter. Combining with the asymptotic behavior (for XXZ case) or the quasi-periodicity properties (for XYZ case) of the transfer matrix, the extended T-Q ansatzes and the corresponding Bethe ansatz equations are derived. (C) 2013 Elsevier B.V. All rights reserved.

We solve a generalized nonautonomous nonlinear Schrodinger equation analytically by performing the Hirota's bilinearization method. The precise expression of a parameter e, which provides a compatibility condition and dark soliton management, is obtained. Comparing with nonautonomous bright soliton, we find that the gain parameter affects both the background and the valley of dark soliton (e2 ≠ 1) while it has no effects on the wave central position. Moreover, the precise expressions of a nonautonomous black soliton's (e2 = 1) width, background and the trajectory of its wave central, which describe the dynamic behavior of soliton's evolution, are investigated analytically. Finally, the stability of the dark soliton solution is demonstrated numerically. It is shown that the main characteristic of the dark solitons keeps unchanged under a slight perturbation in the compatibility condition.

We analytically present a family of nonautonomous dark solitons and rogue waves in a planar graded-index grating waveguide with an additional long-period grating. The dark solitons whose dynamics described by the explicit expressions such as the valley, background and wave central position are investigated. We find that dark soliton's depth and the long-period grating have effects on soliton's wave central position; the gain or loss term affects directly both the background and valley of the soliton. For rogue waves, it is reported that one can modulate the distribution of the light intensity by adjusting the parameters of the long-period grating. Additionally, more rogue waves with different evolution behaviors in this special waveguide are demonstrated clearly.

We study the correspondence between modulational instability and types of fundamental nonlinear excitation in a nonlinear fiber with both third-order and fourth-order effects. Some soliton excitations are obtained in the modulational instability regime which have not been found in nonlinear fibers with second-order effects and third-order effects. Explicit analysis suggests that the existence of solitons is related to the modulation stability circle in the modulation instability regime, and they just exist in the modulational instability regime outside of the modulational stability circle. It should be emphasized that the solitons exist only with two special profiles on a continuous-wave background at a certain frequency. The evolution stability of the solitons is tested numerically by adding some noise to initial states, which indicates that they are robust against perturbations even in the modulation instability regime. Further analysis indicates that solitons in the modulational instability regime are caused by fourth-order effects.

We study symmetric and asymmetric optical multi-peak solitons on a continuous wave background in the femtosecond regime of a single-mode fiber. Key characteristics of such multi-peak solitons, as the formation mechanism, propagation stability, and shape-changing collisions, are revealed in detail. Our results show that this multi-peak (symmetric or asymmetric) mode could be regarded as a single pulse formed by a nonlinear superposition of a periodic wave and a single-peak (W-shaped or antidark) soliton. In particular, a phase diagram for different types of nonlinear excitations on a continuous wave background including breather, rogue wave, W-shaped soliton, antidark soliton, periodic wave, and multi-peak soliton is established based on the explicit link between exact nonlinear wave solution and modulation instability analysis. Numerical simulations are performed to confirm the propagation stability of the multi-peak solitons with symmetric and asymmetric structures. Further, we unveil a remarkable shape-changing feature of asymmetric multi-peak solitons. It is interesting that these shape-changing interactions occur not only in the intraspecific collision (soliton mutual collision) but also in the interspecific interaction (soliton-breather interaction). Our results demonstrate that each multi-peak soliton exhibits the coexistence of shape change and conservation of the localized energy of light pulse against the continuous wave background., Comment: 9 pages, 8 figures

We study multi-peak solitons \textit{on a plane-wave background} in an erbium-doped fiber system with some higher-order effects, which is governed by a coupled Hirota and Maxwel-Bloch (H-MB) model. The important characteristics of multi-peak solitons induced by the higher-order effects, such as the velocity changes, localization or periodicity attenuation, and state transitions, are revealed in detail. In particular, our results demonstrate explicitly that a multi-peak soliton can be converted to an anti-dark soliton when the periodicity vanishes; on the other hand, a multi-peak soliton is transformed to a periodic wave when the localization vanishes. Numerical simulations are performed to confirm the propagation stability of multi-peak solitons riding on a plane-wave background. Finally, we compare and discuss the similarity and difference of multi-peak solitons in special degenerate cases of the H-MB system with general existence conditions., 7 pages, 4 figures

We investigate the thermodynamic limit of the su(n)-invariant spin chain models with unparallel boundary fields. It is found that the contribution of the inhomogeneous term in the associated T-Q relation to the ground state energy does vanish in the thermodynamic limit. This fact allows us to calculate the boundary energy of the system. Taking the su(2) (or the XXX) spin chain and the su(3) spin chain as concrete examples, we have studied the corresponding boundary energies of the models. The method used in this paper can be generalized to study the thermodynamic properties and boundary energy of other high rank models with non-diagonal boundary fields., published version, 21 pages, 4 figures, typos are corrected

We investigate the relationship between two kinds of ground-state local convertibility and quantum phase transitions in XY model. The local operations and classical communications (LOCC) convertibility is examined by the majorization relations and the entanglement-assisted local operations and classical communications (E- LOCC) via Renyi entropy interception. In the phase diagram of XY model, LOCC convertibility and ELOCC convertibility of ground-states are presented and compared. It is shown that different phases in the phase dia- gram of XY model can have different LOCC or ELOCC convertibility, which can be used to detect the quantum phase transition. This study will enlighten extensive studies of quantum phase transitions from the perspective of local convertibility, e.g., finite-temperature phase transitions and other quantum many-body models., 5 pages, 4 figures

We study nonlinear waves on a plane-wave background in an erbium-doped fiber system, which is governed by the coupled nonlinear Schrodinger and the Maxwell–Bloch equations. We find that prolific different types of nonlinear localized and periodic waves do exist in the system, including multi-peak soliton, periodic wave, antidark soliton, and W-shaped soliton (as well as the known bright soliton, breather, and rogue wave). In particular, the dynamics of these waves can be extracted from a unified exact solution, and the corresponding existence conditions are presented explicitly. Our results demonstrate the structural diversity of the nonlinear waves in this system.

The trigonometric su(n) spin chain with anti-periodic boundary condition (su(n) spin torus) is demonstrated to be Yang-Baxter integrable. Based on some intrinsic properties of the R-matrix, certain operator product identities of the transfer matrix are derived. These identities and the asymptotic behavior of the transfer matrix together allow us to obtain the exact eigenvalues in terms of an inhomogeneous T-Q relation via the off-diagonal Bethe Ansatz., Comment: 24 pages, no figure, published version

An orthogonal basis of the Hilbert space for the quantum spin chain associated with the su(3) algebra is introduced. Such kind of basis could be treated as a nested generalization of separation of variables (SoV) basis for high-rank quantum integrable models. It is found that all the monodromy-matrix elements acting on a basis vector take simple forms. With the help of the basis, we construct eigenstates of the su(3) inhomogeneous spin torus (the trigonometric su(3) spin chain with antiperiodic boundary condition) from its spectrum obtained via the off-diagonal Bethe Ansatz (ODBA). Based on small sites (i.e. N=2) check, it is conjectured that the homogeneous limit of the eigenstates exists, which gives rise to the corresponding eigenstates of the homogenous model., Comment: 24 pages, no figure, published version

We investigate the steerability of two-qubit Bell-diagonal states under projective measurements by the steering party. In the simplest nontrivial scenario of two projective measurements, we solve this problem completely by virtue of the connection between the steering problem and the joint-measurement problem. A necessary and sufficient criterion is derived together with a simple geometrical interpretation. Our study shows that a Bell-diagonal state is steerable by two projective measurements iff it violates the Clauser-Horne-Shimony-Holt (CHSH) inequality, in sharp contrast with the strict hierarchy expected between steering and Bell nonlocality. We also introduce a steering measure and clarify its connections with concurrence and the volume of the steering ellipsoid. In particular, we determine the maximal concurrence and ellipsoid volume of Bell-diagonal states that are not steerable by two projective measurements. Finally, we explore the steerability of Bell-diagonal states under three projective measurements. A simple sufficient criterion is derived, which can detect the steerability of many states that are not steerable by two projective measurements. Our study offers valuable insight on steering of Bell-diagonal states as well as the connections between entanglement, steering, and Bell nonlocality., Comment: 12 pages, 5 figures, published in Scientific Reports

We perform a Hamiltonian analysis of the Green-Schwarz sigma model on a supercoset target with 4m grading. The fundamental Poisson brackets between the spatial component of the flat currents depending on a continuous parameter, which can be thought of as a first step in the complete calculation of the algebra of the transition matrices, are obtained. When m = 1, our results are reduced to the results of the type IIB Green-Schwarz superstring on AdS5 × S5 background obtained by Das, Melikyan and Sato.

With the help of the F-basis provided by the Drinfeld twist or factorizing F-matrix for the open XXZ spin chain with non-diagonal boundary terms, we obtain the determinant representation of the partition function of the six-vertex model with a non-diagonal reflecting end under domain wall boundary condition., Comment: Latex file, 24 pages, 4 figures

We construct the explicit free field representations of the current algebras $so(2n)_k$, $so(2n+1)_k$ and $sp(2n)_k$ for a generic positive integer $n$ and an arbitrary level $k$. The corresponding energy-momentum tensors and screening currents of the first kind are also given in terms of free fields., Comment: Latex file, 25 pages

The decomposition of $Spin^{c}(4)$ gauge potential in terms of the Dirac 4% -spinor is investigated, where an important characterizing equation $\Delta A_{\mu}=-\lambda A_{\mu}$ has been discovered. Here $\lambda $ is the vacuum expectation value of the spinor field, $\lambda =\Vert \Phi \Vert ^{2}$, and $A_{\mu}$ the twisting U(1) potential. It is found that when $\lambda $ takes constant values, the characterizing equation becomes an eigenvalue problem of the Laplacian operator. It provides a revenue to determine the modulus of the spinor field by using the Laplacian spectral theory. The above study could be useful in determining the spinor field and twisting potential in the Seiberg-Witten equations. Moreover, topological characteristic numbers of instantons in the self-dual sub-space are also discussed.

The normal function of excision repair cross complementing group 1 (ERCC1) is essential for maintaining genomic integrity and preventing cellular neoplastic transformation, and multiple studies have reported an association between ERCC1 polymorphisms and increased risk of cancers. To test whether the genetic variants of ERCC1 gene modify the risk of nasopharyngeal carcinoma (NPC), we compared the 8092 C > A and 19007 C > T single nucleotide polymorphisms (SNPs) and the haplotypes of ERCC1 between 267 patients with NPC and 304 healthy controls. Linkage disequilibrium was observed between the two SNPs loci (D′ = 0.861). Significant differences of allele frequencies were found for ERCC1 8092C > A between the cases and controls. Individuals with 8092 C allele showed 1.411-fold (OR = 1.411, 95% CI, 1.076–1.850, P = 0.014) increased risk of developing NPC, and the CC haplotype was associated with a significantly increased risk of NPC (OR = 1.712; 95% CI, 1.211–2.421; P = 0.013). No interactions were found between 8092C > A polymorphism and genders, smoking status and alcohol consumption. These results suggested that the polymorphism of ERCC1 8092 C > A might be a contributing factor in the development of NPC in Chinese population. © 2008 Wiley-Liss, Inc.

We study two-dimensional nonlinear sigma models with target spaces being the complex super Grassmannian manifolds, that is, coset supermanifolds $G(m,p|n,q)\cong U(m|n)/[U(p|q)\otimes U(m-p|n-q)]$ for $0\leq p \leq m$, $0\leq q \leq n$ and $1\leq p+q$. The projective superspace ${\bf CP}^{m-1|n}$ is a special case of $p=1$, $q=0$. For the two-dimensional Euclidean base space, a wide class of exact classical solutions (or harmonic maps) are constructed explicitly and elementarily in terms of Gramm-Schmidt orthonormalisation procedure starting from holomorphic bosonic and fermionic supervector input functions. The construction is a generalisation of the non-super case published more than twenty years ago by one of the present authors., Comment: Latex file, 17 pages; V2, typos corrected, this version will appear in Nucl. Phys. B