Search

Dynamical modelling for neural systems with direct and indirect connections is to understand how these connections contribute to neural dynamics. Despite recent findings suggesting the existence of indirect connections in neural systems, their dynamical characteristics remain poorly understood. In this paper, we propose a simplified circuit model with indirect interactions inspired by the indirect connection between two neurons, from an energy perspective. Through bifurcation and dynamics analysis, we find that the presented model has a striking resemblance with the classical Hodgkin-Huxley neuronal model. Moreover, stability in a neural network coupled with energy is demonstrated by combining stability analysis and numerical simulation. Our analysis sheds light on the excitability dynamics and multi-stability that can emerge in biophysical systems with nonlinear interactions inspired by the neural systems and highlights the role of energy in propagating electrical activities. • We construct a neuron-inspired circuit model with indirect interactions involving energy. • The neuron-like excitability and bi-stability are identified in the neuron-inspired circuit. • The neuron-inspired circuit can reproduce excitability as same bifurcation mechanism as the HH neuron. • Stability conditions of the neural network are deduced by stability analysis. • Multistability is triggered in the neural network with different coupling matrix. [ABSTRACT FROM AUTHOR]

In this paper, we provide theoretical as well as numerical results concerning recurrent oscillations in Cohen-Grossberg neural networks with variable inputs and strengths of connectivity for cells, which are unpredictable or Poisson stable functions. A special case of the compartmental coefficients with periodic and unpredictable ingredients is also carefully researched. By numerical and graphical analysis, it is shown how a constructive technical characteristic, the degree of periodicity, reflects contributions of the ingredients to final outputs of the neural networks. Sufficient conditions are obtained to guarantee the existence of exponentially stable unpredictable outputs of the models. They are specified for Poisson stability by utilizing the original method of included intervals. Examples with numerical simulations that support the theoretical results are provided. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we focus on driving a class of directed networks to achieve cluster synchronization by pinning schemes. The desired cluster synchronization states are no longer decoupled orbits but a set of un-decoupled trajectories. Each community is considered as a whole and the synchronization criteria are derived based on the information of communities. Several pinning schemes including feedback control and adaptive strategy are proposed to select controlled communities by analyzing the information of each community such as indegrees and outdegrees. In all, this paper answers several challenging problems in pinning control of directed community networks: (1) What communities should be chosen as controlled candidates? (2) How many communities are needed to be controlled? (3) How large should the control gains be used in a given community network to achieve cluster synchronization? Finally, an example with numerical simulations is given to demonstrate the effectiveness of the theoretical results. [Copyright &y& Elsevier]

This paper concerned with a delayed diffusive eco-epidemiological model with fear effect. First, we discuss the existence and boundedness of the solution of the system. Then we give some conditions for the existence and stability of the nonnegative equilibria, and Turing instability. Furthermore, we choose the delay as bifurcation parameter to study Hopf bifurcation. Finally, we present some numerical simulations to verify our theoretical results. By mathematical and numerical analyses, we find that the fear can prevent the occurrence of limit cycle oscillation and increase the stability of the system, and the diffusion can induce the spatial pattern in the system. • We propose a delayed diffusive eco-epidemiological model with fear effect. • We have studied Hopf bifurcation and Turing bifurcation of the model. • We have discussed the global stability of the equilibria. • The results show that system can generate a wide variety of spatial patterns. [ABSTRACT FROM AUTHOR]

The aim of this paper is to construct and analyze a mathematical model for the response of T-cytotoxic lymphocytes to the Ebola virus using the Herz-tuckwill model with nonlinear Conformable order differential equations which derive from real biological data, then study the global stability of the equilibria using an appropriate Lyapunov function and the LaSalle invariance principle. Furthermore, we demonstrate the impact of the non-integer order of the model compared with the integral order. Finally consider a numerical simulation that justifies the biological hypotheses and the theory results. The numerical results provided that, the non-integer order has a great impact on the treatments of Ebola virus in this model. [ABSTRACT FROM AUTHOR]

Abstract: This paper investigates the problem of function projective synchronization (FPS) in drive–response dynamical networks (DRDNs) with non-identical nodes. Based on the adaptive open-plus-closed-loop (AOPCL) method, a general method of function projective synchronization is derived, which is robust to limited accuracy of data and effects of noise. Corresponding numerical simulations on the Lorenz system are performed to verify and illustrate the analytical results. [Copyright &y& Elsevier]

Abstract: In this paper, we obtain some oscillation criteria for a class of neutral difference equations with time delays. We also investigate the behavior of the eventually positive solutions of these equations. To verify our results we give various numerical simulations by using the MATLAB programming. [Copyright &y& Elsevier]

A lot of results for continuous-time memristor (CM) have been obtained. However, discrete memristor (DM), especially non-autonomous discrete memristor (NDM), has not been received adequate attention. In this paper, a new NDM model is proposed. Just only based on this model, a simple 2D NDM-based hyperchaotic (NDMH) map owning a line of fixed points is established. The NDMH map behaves several complex dynamical motions, including hyperchaos, bifurcation with parameters, and different forms of periodic and transient chaotic bursting oscillations. Meanwhile, the stability of fixed points is studied and the relationship with bifurcations and bursting oscillations is explored by theoretical analyses and numerical simulations. [ABSTRACT FROM AUTHOR]

• COVID-19 modeling transmission using known theory concerning the disease transmission and control strategies. • Formulation of a mathematical model for the COVID-19 that incorporates some key epidemiological and biological features. • Sensitivity analysis of the model. • Theoretical studies and numerical simulations. In this paper, we formulated a general model of COVID-19 model transmission using biological features of the disease and control strategies based on the isolation of exposed people, confinement (lock-downs) of the human population, testing people living risks area, wearing of masks and respect of hygienic rules. We provide a theoretical study of the model. We derive the basic reproduction number R 0 which determines the extinction and the persistence of the infection. It is shown that the model exhibits a backward bifurcation at R 0 = 1. The sensitivity analysis of the model has been performed to determine the impact of related parameters on outbreak severity. It is observed that the asymptomatic infectious group of individuals may play a major role in the spreading of transmission. Moreover, various mitigation strategies are investigated using the proposed model. A numerical evaluation of control strategies has been performed. We found that isolation has a real impact on COVID-19 transmission. When efforts are made through the tracing to isolate 80% of exposed people the disease disappears about 100 days. Although partial confinement does not eradicate the disease it is observed that, during partial confinement, when at least 10% of the partially confined population is totally confined, COVID-19 spread stops after 150 days. The strategy of massif testing has also a real impact on the disease. In that model, we found that when more than 95% of moderate and symptomatic infected people are identified and isolated, the disease is also really controlled after 90 days. The wearing of masks and respecting hygiene rules are fundamental conditions to control the COVID-19. [ABSTRACT FROM AUTHOR]

In this paper, we present mathematical analysis and numerical simulation of a three-dimensional autonomous fractional system with coexistence of multi-scroll chaotic attractors. We replaced the classical derivatives of such system with the Caputo-Fabrizio fractional derivative. This derivative combines both the exponential laws and non-singular kernels in its formulation which makes it special and useful. A two-step Adams-Bashforth scheme is derived for the approximation of the fractional derivative with exponential law and non-singular kernel. We then presented both numerical results and graphical results by considering many values of the fractional-order parameter β ∈ (0, ]. We demonstrate that the observed chaotic behavior conduct perseveres as the fractional-order parameter approaches 1. [ABSTRACT FROM AUTHOR]

In this paper, we suggest a new integro-differential equation by utilizing from the concept of fractal-fractional derivative and integral newly introduced by Atangana. We offer that under which conditions the solution of the suggested equation is exist and unique benefitting from Banach fixed-point theorem. Also, we construct a new numerical scheme for the numerical solution of our problem and we give numerical simulation and illustrations for different values of fractional order α and fractal order β. That's why, this study will guide for researchers significantly in theory and applications. [ABSTRACT FROM AUTHOR]