Intracellular calcium (Ca) alternans has been widely studied in cardiac myocytes and tissue, yet the underlying mechanism remains controversial.In this study, we used computational modeling simulation to study how randomly occurring Ca sparks interact collectively result whole-cell alternans.We developed a spatially distributed intracellular cycling model which release units (CRUs) are locally coupled by diffusion throughout myoplasm sarcoplasmic reticulum (SR) network. occur CRU network...

The collective behaviors of coupled, stochastically excitable elements subjected to global periodic forcing are investigated numerically and analytically. We show that the whole system undergoes a period-doubling bifurcation as driving period decreases, while individual still exhibit random excitations. Using mean-field representation, we this macroscopic behavior is caused by interactions between excitation, refractory period, recruitment (spatial cooperativity) elements.

Spontaneous activity of the human brain provides a window to explore intrinsic principles functional organization. However, most studies have focused on interregional connectivity. The underlying rich repertoires instantaneous remain largely unknown. We apply recently proposed eigen-microstate analysis three resting-state MRI datasets identify basic modes that represent fundamental patterns coexist over time. five leading dominate fluctuations. Each mode exhibits distinct system-dependent...

Abstract Reservoir computing, a new method of machine learning, has recently been used to predict the state evolution various chaotic dynamic systems. It significant advantages in terms training cost and adjusted parameters; however, prediction length is limited. For classic reservoir can only reach five six Lyapunov times. Here, we modified computing by adding feedback, continuous or discrete, “calibrate” input then reconstruct entire The reconstruction appreciably increased obviously...

In this paper we study nonlinear oscillatory systems consisting of two media, one supporting forward propagating waves and the other inwardly waves, separated by an interface. We find that interface can select type wave. Under certain well-defined parameter condition, these propagate in different media with same frequency wave number; is transparent to waves. The number interface-selected (ISWs) are predicted explicitly. When parameters varied from set, numbers domains become different,...

Spatial networks play a central role in the analysis of real-world systems' structures. However, modelling spatial remains challenge, primarily due to elusive mechanisms governing emergence loops. Since loops are intimately related network functionality, it is imperative gain an understanding their formation. Early models, often based on top-down planning, tend overlook evolving nature networks, resulting exceedingly high computational complexity. To address these limitations, self-organized...

Abstract The competition of waves has remained a hot topic in physics over the past few decades, especially area pattern control. Because improved understanding various dynamic behaviors, many practical applications have sprung up recently. prediction wave competitions is also very important and quite useful these fields. This paper considers behaviors simple, inhomogeneous media which modeled by Brusselator equations. We present simple rule to judge results utilizing dispersion relation...

The investigation of self-sustained oscillations in excitable complex networks is very important understanding various activities brain systems, among which the exploration key determinants a challenging task. In this paper, by investigating influence system parameters on Erdös-Rényi random (EERRNs), minimum Winfree loop (MWL) revealed to be factor determining emergence collective oscillations. Specifically, one-to-one correspondence between optimal connection probability (OCP) and MWL...

The sinoatrial node (SAN)-atrium system is closely involved with the activity of heart beating. impulse propagation and phase-locking behaviors this are theoretical interest. Some experiments have revealed that atrial strands (ASs) interdigitate penetrate into SAN, whereby SAN-atrium works as a complex network. In study, functions ASs numerically investigated using realistic cardiac models. results indicate penetrating central region SAN play major role in propagating excitation atrium. This...

Wave competition is an important phenomenon for pattern formation and control, which are required in many practical applications. In this work we consider the of wave trains around interfaces two one-dimensional oscillatory media, modeled by complex Ginzburg-Landau equations with different system control parameters. The generated pacings at boundaries media. presence both normal antiwave trains, extremely rich phenomena can be observed varying parameters systems. These behaviors fully...

Abstract Wave propagation is an important characteristic for pattern formation and dynamics. To date, various waves in homogeneous media have been investigated extensively understood to a great extent. However, the wave behaviors heterogeneous studied much less. In this work, we investigate that are spontaneously generated one-dimensional oscillatory governed by complex Ginzburg-Landau equations; heterogeneity modeled multiple interacting with different system control parameters. Rich can be...

Recently, waves propagating with negative phase velocity [simply called antiwaves (AWs)] have attracted great attention in the area of nonlinear oscillatory systems. In present work we investigate parameter conditions for AWs. So far AWs been revealed from systems slightly beyond Hopf bifurcation or some other instabilities, and wave sources certain restricted frequencies. Here study general media (including generalized complex Ginzburg-Landau Brusselator model) specify by characteristic...

In the present letter we propose a robust method to optimize conventional heterogeneous patching (HP) of controlling pattern formation in oscillatory systems. Normal patch controllers always leave visible imprints making final patterns imperfect. Our optimal HP uses normal wave (antiwave) media as patched control dynamics antiwave (normal wave) media. With properly selected and controllers, this can modulate systems desired with themselves entirely hidden homogeneous patterns. This favorable...

Scientists have been familiar with various phenomena of wave propagation for several centuries, such as reflection, diffraction, normal and negative refraction in both linear nonlinear systems. However, there has no report about imagery systems which is a well-known phenomenon optics. By periodically pacing small area medium one side the interface, we reveal target other interface. We demonstrate that unlike what happens optics, certain proper parameter sets, imaging waves can form without...

Recently, inwardly propagating waves (called antiwaves, AWs) in nonlinear oscillatory systems have attracted much attention. An interesting negative refraction phenomenon has been observed a bidomain system where one medium supports forwardly (normal waves, NWs) and the other AWs. In this paper we find that (NR) media an asymmetric property, i.e., NR can be only by applying wave source with proper frequency to medium, but not other. Moreover, appears always when incident are dense...

The study of specific physiological processes from the perspective network physiology has gained recent attention. Modeling global information integration among separated functionalized modules in structural and functional brain networks is a central problem. In this article, preferentially cutting–rewiring operation (PCRO) introduced to approximatively describe above process, which consists cutting procedure rewiring with preferential constraints. By applying PCRO on classical Erdös–Rényi...

Network diffusion processes play an important role in solving the information overload problem. It has been shown that diffusion-based recommendation methods have advantage to generate both accurate and diverse items for online users. Despite that, numerous existing works consider rating as link weight or threshold retain useful links, few studies use evaluate results. In this paper, we measure average of recommended products, finding risk recommending low-rated products addition, improve...

In this paper, we extensively investigate the oscillation-mode dynamics in excitable homogeneous random networks (EHRNs) and corresponding determinants. It is exposed that, at a certain set of system parameters, there exists two kinds oscillation modes, i.e., major mode (MajOM) minor (MinOM). Moreover, these groups can be effectively impacted by types dynamics, transfer transition, have been revealed explicitly. Importantly, minimum Winfree loop (MWL) excitation threshold as determinants...