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Finite/fixed-time controls for multiagent systems (MASs) in cooperative and competitive networks have been discussed intensively, and the structural balance and gauge transformation play a crucial role in analyzing the finite/fixed-time bipartite cooperative behavior of MASs. However, the structural balance for a large-sized network is not easy to verify, and it is uncertain whether the gauge transformation is feasible for nonlinear networks. Without adopting the gauge transformation, this article considers finite/fixed-time bipartite controls of nonlinear neural networks (NNs) with cooperative and competitive interactions. A matrix $M$ in cooperative networks is extended to a general one in cooperative and competitive networks to design quadratic Lyapunov functions. On this basis, the finite/fixed-time bipartite synchronization criteria and adjustment times are obtained, which avoids adopting the gauge transformation in a nonlinear system. The negative cycle is found to have a very important effect on the dynamic behavior of NNs. Numerical examples validate the proposed bipartite controls of NNs in a signed graph.

AbstractCoal seam mining causes movement and deformation of the overlying rock mass and ground surface, directly resulting in serious damage to the surface construction facilities. To investigate the deformation mechanism and characteristics of the overlying rock mass, three-dimensional numerical simulation and model test are carried out on an open-pit mine slope. The results show that the sliding instability characteristics of the slope can be identified based on the numerical analysis. Coal mining affects on the deformation characteristics of the overlying rock mass near the inner dump. The closer to the slope boundary, the greater the subsidence of overlying rock mass. The maximum displacement occurs near the inner dump. The slope mining has great influence on the deformation characteristics of inner dump. Moreover, the damage process of overlying rock mass can be further studied viathe model test. After coal seams mining out, the overlying rock mass occurs overall settlement failure. There is a large difference between the lower end side of working face and the upper end side at the caving angle of roof. This work can provide a basis for the safe operation of coal mine disaster prevention and mitigation.

Interval bipartite consensus of multiagents described by signed graphs has received extensive concern recently, and the rooted cycles play a critical role in stabilization, while the structurally balanced graphs are essential to achieve bipartite consensus. However, the gauge transformation used in the linear system is no longer feasible in the nonlinear case. This article addresses interval bipartite synchronization of multiple neural networks (NNs) in a signed graph via a Lyapunov-based approach, extending the existing work to a more practical but complicated case. A general matrix M in signed graphs is introduced to construct the novel Lyapunov functions, and sufficient conditions are obtained. We find that the rooted cycles and the structurally balanced graphs are essential to stabilize and achieve bipartite synchronization. More importantly, we discover that the nonrooted cycles are crucial in reaching interval bipartite synchronization, not previously mentioned. Several examples are presented to illustrate interval bipartite synchronization of multiple NNs with signed graphs.

The time-triggered impulsive controls were widely used to study the collective behavior of homogeneous dynamical networks due to their low control cost, which was a bit conservative in the occupation of communication channels. This article addresses designing the event-triggered impulsive controls for the quasisynchronization, namely, a weak cooperative behavior with the synchronization error no more than a positive constant in the leader-following heterogeneous dynamical network, which thus can reduce the occupation of resources significantly. The centralized and distributed impulsive controls are designed to lead the followers to synchronize approximately to the leader within a nonzero bound, where the impulsive instants are triggered, respectively, by the global or local state-dependent conditions. Numerical results are put forward to verify the effectiveness of the proposed methods.

This brief is primarily devoted to the predefined-time average consensus of heterogeneous nonlinear leaderless multi-agent systems (MASs). Firstly, the predefined-time stability for a class of fixed-time stable systems is studied, which greatly improves the overestimation for the settling time of the fixed-time stability. Moreover, compared with the classical conclusions, our results are more suitable for the control of nonlinear MASs. Then, on the basis of the proposed stability analysis, a simple control algorithm is designed for ensuring the predefined-time average consensus of the system under consideration. With this predefined-time approach, any desired settling time can be achieved by adjusting the control gain. Finally, numerical simulation is shown to support the theoretical analysis.

The cooperation of linear multiagent systems (MASs) in the signed graphs has received wide attention. However, time delays and nonlinearity are ignored. This article deals with the cooperation behavior, especially interval bipartite synchronization (IBS) of delayed nonlinear neural networks (NNs) with signed graphs. A generalized matrix is proposed for the construction of the Lyapunov functionals, establishing sufficient conditions in a linear matrix inequality related to the coupling strength, the delays, and the network structure. It suggests that the negative rooted cycles and the negative nonrooted cycles take an important part in stabilizing delayed nonlinear NNs and leading to their diversity, and time delays, especially communication delays, significantly impact cooperation performance. Numerical examples are employed to validate our derived results.

AbstractA mathematical model reflecting the evolution of both particle breakage and particle-size distribution (PSD) for rockfill subjected to triaxial shear has been proposed in this article. First, the PSD of a soil is expressed by a gradation equation which has been shown to be widely applicable by comparison with a large amount of test data from soils encountered in practice. Then two particle breakage factors Bgand Brare suggested and proved to be two suitable breakage factors in the model. Mathematical relationships between Bg, Brand the gradation equation’s parameters band mare derived. Then, correlations between the two breakage factors, effective mean normal stress and generalised shear strain during shearing are expressed by empirical functions, with several drained triaxial compression test data verifying the applicability. The inter-relationships of particle breakage, PSD and stress state of rockfill are thereby established, providing what is termed the PSD evolution model. Additionally, the proposed PSD evolution model is verified by successfully predicting the particle breakage factors and PSDs of rockfill triaxial specimens.

The leader-following consensus problem for second-order multi-agent systems is investigated in this paper. The topology of the system is directed and the dynamics of each agent is nonlinear. Based on the intermittent control strategy and the adaptive control method, a mixed protocol for each follower is designed. Using the Lyapunov stability theory, sufficient conditions are derived such that all the followers can track the leader. Finally, some numerical simulation results are presented to demonstrate the effectiveness of the proposed consensus protocol.

Although magnesium (Mg) is one of the most important nutrients, involved in many enzyme activities and the structural stabilization of tissues, its importance as a macronutrient ion has been overlooked in recent decades by botanists and agriculturists, who did not regard Mg deficiency (MGD) in plants as a severe health problem. However, recent studies have shown, surprisingly, that Mg contents in historical cereal seeds have markedly declined over time, and two thirds of people surveyed in developed countries received less than their minimum daily Mg requirement. Thus, the mechanisms of response to MGD and ways to increase Mg contents in plants are two urgent practical problems. In this review, we discuss several aspects of MGD in plants, including phenotypic and physiological changes, cell Mg2+homeostasis control by Mg2+transporters, MGD signaling, interactions between Mg2+and other ions, and roles of Mg2+in plant secondary metabolism. Our aim is to improve understanding of the influence of MGD on plant growth and development and to advance crop breeding for Mg enrichment.

Salvia miltiorrhiza, a popular traditional Chinese medicine, is widely used for treatments in cardiotonic disease. Tanshinones are a group of bioactive ingredients in S. miltiorrhiza.In this study, Ce3+was used as an elicitor to enhance tanshinones production in S. miltiorrhizahairy roots. The results showed that contents of dihydrotanshinone I (DTI) and cryptotanshinone (CT) were significantly enhanced by 50 μmol/L Ce3+, and reached to 0.875 mg/g and 0.271 mg/g, respectively. However, tanshinone II A (TIIA) and tanshinone I (TI) contents were significantly decreased to 59% and 62% of the control. Simultaneously, expressions of genes (HMGR, DXR, DXS1, DXS2and GGPPS) involved in tanshinone biosynthesis were upregulated by Ce3+. Responses of DXS1, DXS2and GGPPSto Ce3+treatments were later than HMGRand DXR. We speculated that branch pathways of DTI and CT biosynthesis were probably different from TIIA and TI. This work will help us understand biosynthetic mechanism of tanshinones in plants.

This article investigates the consensus problem of the second-order multi-agent systems with an active leader and coupling time delay in direct graph. One decentralized state control rule is constructed for each agent to track the active leader and it is proved that the proposed control scheme enables the consensus to be obtained when the adjacency topology is fixed/switched. Simulation results show effectiveness of the proposed theoretical analysis.

There is an explosive interest in rodlike vanadium oxide nanomaterials. This review discusses the current research activities on vanadium oxide nanorods in our group. We begin this paper with a variety of chemical and physical methods that have been used to synthesize vanadium oxide nanorods. There follows a discussion of techniques for adjusting vanadium oxide nanorods by doping, ordered constructing, Langmuir−Blodgett assembly, etc. At the end of this paper, we discuss a wide range of interesting properties, such as electrochemical, electrical, optical, magnetic, and field-emission properties, associated with vanadium oxide nanorods, as well as various intriguing applications. We conclude with personal remarks on the outlook for research on vanadium oxide nanorods.

Robinia ambiguavar. idahoensis, presumably originated from interspecific hybridization of R. pseudoacaciaL. and R. hispidaL., is a multipurpose tree. Several reports have showed that in vitromicropropagation is a feasible method to produce large quantities of ‘clonal’ plants from R. pseudoacacia, however, no information is available on micropropagation of R. ambiguaor the other assumed parental species, R. hispida. Here, we report on a tissue culture system for efficient micropropagation of R. ambiguaplants by enhanced branching of axillary buds taken from a single branch of a donor tree. The culture system consists of sequential use of three media, namely, the bud-induction medium (MS medium supplemented with 0.8–1.4 mg l−16-BA, 0.05–0.08 mg l−1NAA and 0.07–0.1 mg l−1GA), elongation medium (MS medium added with 0.35–0.5 mg l−16-BA, 0.05–0.08 mg l−1NAA and 0.07–0.1 mg l−1GA) and root-induction medium (1/4 MS medium fortified with 1.7–2.5 mg l−1IAA and 0.1–0.5 mg l−1IBA). In addition, we investigated the genetic stability (relative to the donor plant) of a sample of 41 morphologically normal plants randomly taken from ca. 13,000 micropropagated plants, by using the inter-simple sequence repeat (ISSR) marker with 32 selected primers. We found that of the 226 reproducible bands scored, 24 were polymorphic (10.62%), thus pointing to the occurrence, though at a relatively low level compared with an earlier study on R. pseudoacacia, of genomic variation in these micropropagated plants. Further sequencing on seven loci underlying the variations showed that two had significant homology to known or predicted plant genes.Robinia ambiguavar. idahoensis, presumably originated from interspecific hybridization of R. pseudoacaciaL. and R. hispidaL., is a multipurpose tree. Several reports have showed that in vitromicropropagation is a feasible method to produce large quantities of ‘clonal’ plants from R. pseudoacacia, however, no information is available on micropropagation of R. ambiguaor the other assumed parental species, R. hispida. Here, we report on a tissue culture system for efficient micropropagation of R. ambiguaplants by enhanced branching of axillary buds taken from a single branch of a donor tree. The culture system consists of sequential use of three media, namely, the bud-induction medium (MS medium supplemented with 0.8–1.4 mg l−16-BA, 0.05–0.08 mg l−1NAA and 0.07–0.1 mg l−1GA), elongation medium (MS medium added with 0.35–0.5 mg l−16-BA, 0.05–0.08 mg l−1NAA and 0.07–0.1 mg l−1GA) and root-induction medium (1/4 MS medium fortified with 1.7–2.5 mg l−1IAA and 0.1–0.5 mg l−1IBA). In addition, we investigated the genetic stability (relative to the donor plant) of a sample of 41 morphologically normal plants randomly taken from ca. 13,000 micropropagated plants, by using the inter-simple sequence repeat (ISSR) marker with 32 selected primers. We found that of the 226 reproducible bands scored, 24 were polymorphic (10.62%), thus pointing to the occurrence, though at a relatively low level compared with an earlier study on R. pseudoacacia, of genomic variation in these micropropagated plants. Further sequencing on seven loci underlying the variations showed that two had significant homology to known or predicted plant genes.

It has been demonstrated that insertion of foreign DNA into mammalian genome can profoundly alter the patterns of DNA methylation and transcription of the host genome. Introgression of alien DNA into plant genomes through sexual crossing and genetic engineering are commonly used in breeding, but it is not known if plant genomes have similar responses to alien DNA introgression as those of animals. Two stable rice lines with introgression from wild rice, Zizania latifolia, were analyzed for patterns of cytosine DNA methylation and transcription of a set of selected sequences, including cellular genes and transposable element (TE)-related DNA segments. In 21 of the 30 studied sequences, marked changes in DNA methylation and/or transcription were observed compared with those of the rice parent. In all analyzed sequences, the absence of Zizaniahomologues in the introgression lines was confirmed. No change in DNA methylation and expression patterns was detected in randomly selected individuals of the rice parent nor in two sibling lines without introgressed ZizaniaDNA. The changed methylation patterns in both introgression lines were stably maintained in all five randomly sampled individuals of a given line, as well as in selfed progenies of the lines. Changed patterns in methylation and expression were also found in an independently produced asymmetric somatic nuclear hybrid (SH6) of rice and Z. latifoliathat involves a different rice genotype but also contains a small amount of Z. latifoliaDNA integrated into the rice genome. Thus, we have demonstrated that alien DNA introgression into a plant genome can induce extensive alterations in DNA methylation and transcription of both cellular genes and TE-related DNA segments in a genotype-independent manner.

Magnesium (Mg) is one of the most important nutrients, involves mainly in plant growth and development. However, the signaling pathways response to magnesium stresses (MgSs) is known little, but several studies lately may improve the research development. Several phytohormones such as abscisic acid (ABA), ethylene, auxins, and their factors were found responding to MgSs, and there may be some signal pathways linking these hormones and downstream reactions together, e.g., carbon fixation and transfer, starch and sugar metabolism, ion uptaking and reactive oxygen species (ROS) increasing. Consequently, Arabidopsis morphogenesis is remodeled. In this review, we mainly discussed recent literatures involving in plant response to MgSs (Mg deficiency (MgD) and Mg toxicity (MgT)), including plant morphogenesis remodeling, magnesium transporters and signaling transductions. Moreover, the future study challenges related to the responding signalings to MgSs in plants are also presented. Regardless, the iceberg of signal transduction of MgSs in plants is appeared.