Chaos最新文献_第6页

Power Levy motion. II. Evolution. 电力征收动议。2。进化。

IF 2.7 2区数学

Chaos Pub Date : 2025-03-01 DOI: 10.1063/5.0251341

Iddo Eliazar

引用次数: 0

Sensitivities in complex-time flows: Phase transitions, Hamiltonian structure, and differential geometry. 复杂时间流的敏感性：相变、哈密顿结构和微分几何。

IF 2.7 2区数学

Chaos Pub Date : 2025-03-01 DOI: 10.1063/5.0245642

Dirk Lebiedz, Johannes Poppe

引用次数: 0

Devil's staircase inside shrimp-shaped regions reveals periodicity of plateau spikes and bursts. 虾形区域内的魔鬼阶梯显示了高原尖峰和爆发的周期性。

IF 2.7 2区数学

Chaos Pub Date : 2025-03-01 DOI: 10.1063/5.0250342

Luiz F B Caixeta, Matheus H P Gonçalves, M H R Tragtenberg, Mauricio Girardi-Schappo

{"title":"Devil's staircase inside shrimp-shaped regions reveals periodicity of plateau spikes and bursts.","authors":"Luiz F B Caixeta, Matheus H P Gonçalves, M H R Tragtenberg, Mauricio Girardi-Schappo","doi":"10.1063/5.0250342","DOIUrl":"https://doi.org/10.1063/5.0250342","url":null,"abstract":"Slow-fast dynamics are intrinsically related to complex phenomena and are responsible for many of the homeostatic dynamics that keep biological systems healthy functioning. We study a discrete-time membrane potential model that can generate a diverse set of spiking behavior depending on the choice of slow-fast time scales, from fast spiking to bursting, or plateau action potentials-also known as cardiac spikes since they are characteristic in heart myocytes. The plateau of cardiac spikes can lose stability, generating early or delayed afterdepolarizations (EADs and DADs, respectively), both of which are related to cardiac arrhythmia. We show the periodicity changes along the transition from the healthy action potentials to these impaired oscillations. We show that while EADs are mainly periodic attractors, DADs usually come with chaos. EADs are found inside shrimp-shaped regions of the parameter space. However, in our system, multiple periodic attractors live within a shrimp-shaped region, giving it an internal structure made of infinite transitions between periodicities forming a complete devil's staircase. Understanding the periodicity of plateau attractors in slow-fast systems could be useful in unveiling the characteristics of heart myocyte behaviors that are linked to cardiac arrhythmias.","PeriodicalId":9974,"journal":{"name":"Chaos","volume":"35 3","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143630220","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Nonlinear mechanisms for enhanced and synchronized post-inhibitory rebound spiking associated with seizures in an inhibitory-excitatory neuronal network. 抑制性-兴奋性神经元网络中与癫痫发作相关的增强和同步抑制后反弹峰的非线性机制。

IF 2.7 2区数学

Chaos Pub Date : 2025-03-01 DOI: 10.1063/5.0232718

Yanbing Jia, Huaguang Gu, Xianjun Wang

{"title":"Nonlinear mechanisms for enhanced and synchronized post-inhibitory rebound spiking associated with seizures in an inhibitory-excitatory neuronal network.","authors":"Yanbing Jia, Huaguang Gu, Xianjun Wang","doi":"10.1063/5.0232718","DOIUrl":"https://doi.org/10.1063/5.0232718","url":null,"abstract":"Recent experimental observations on seizures showed that the optogenetic activation of inhibitory interneurons cannot suppress but enhance the frequency and synchronization of spiking of excitatory pyramidal neurons, i.e., synchronized post-inhibitory rebound (PIR) spiking. This complex phenomenon presents paradoxical functions of interneurons and novel etiologies of seizures. In the present study, nonlinear mechanisms and conditions of the synchronized PIR spiking are obtained in a network model of inhibitory interneurons and excitatory pyramidal neurons. Pyramidal neurons with low spiking frequency near the bifurcation, characterized by small conductances (gh) of the hyperpolarization-activated cation (Ih) current and small applied current, are easy to generate PIR spiking. Strong optogenetic stimulation activating interneurons with high spiking frequency and inhibitory synapses with large conductances contribute to the PIR spiking. Moreover, after the optogenetic stimulation, the excitatory synaptic current from pyramidal neurons to interneurons can induce spiking of interneurons to reduce the PIR spiking. Reducing the membrane potential of interneurons can enhance the range of excitatory synaptic conductances for PIR spiking. The PIR spiking can be interpreted by complex nonlinear interactions between the hyperpolarization activation of the Ih current and membrane potential modulated by gh and inhibitory stimulation. Furthermore, higher synchronization degrees of the PIR spiking appear for the spiking with lower frequency. During the inhibitory stimulation, pyramidal neurons become silence with a small difference in membrane potential, which remains within long intervals between spikes and results in strong synchronization after stimulation. The nonlinear mechanisms and conditions of the synchronized PIR spiking are helpful for recognizing and modulating seizures.","PeriodicalId":9974,"journal":{"name":"Chaos","volume":"35 3","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143604003","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Quantifying wave propagation in a chain of FitzHugh-Nagumo neurons. 量化FitzHugh-Nagumo神经元链中的波传播。

IF 2.7 2区数学

Chaos Pub Date : 2025-03-01 DOI: 10.1063/5.0239976

L Messee Goulefack, C Masoller, R Yamapi, C Anteneodo

引用次数: 0

Structure-and-embedding-based centrality on network fragility in hypergraphs. 基于结构和嵌入的超图网络脆弱性中心性。

IF 2.7 2区数学

Chaos Pub Date : 2025-03-01 DOI: 10.1063/5.0232539

Lanlan Chang, Tian Qiu, Guang Chen

引用次数: 0

Amplitude-sensitive permutation entropy: A novel complexity measure incorporating amplitude variation for physiological time series. 振幅敏感排列熵：一种新的生理时间序列振幅变化复杂性测度。

IF 2.7 2区数学

Chaos Pub Date : 2025-03-01 DOI: 10.1063/5.0245842

Jun Huang, Huijuan Dong, Na Li, Yizhou Li, Jing Zhu, Xiaowei Li, Bin Hu

{"title":"Amplitude-sensitive permutation entropy: A novel complexity measure incorporating amplitude variation for physiological time series.","authors":"Jun Huang, Huijuan Dong, Na Li, Yizhou Li, Jing Zhu, Xiaowei Li, Bin Hu","doi":"10.1063/5.0245842","DOIUrl":"https://doi.org/10.1063/5.0245842","url":null,"abstract":"Physiological time series, such as electrocardiogram (ECG) and electroencephalogram (EEG) data, are instrumental in capturing the critical dynamics of biological systems, including cardiovascular behavior and neural activity. The traditional permutation entropy (PE) methods effectively analyze the complexity of such signals but often overlook amplitude variations, which encode essential information about physiological states and pathological conditions. This paper introduces amplitude-sensitive permutation entropy (ASPE), a novel method that enhances PE by integrating amplitude information through the coefficient of variation as a weighting factor. Unlike the existing approaches that may overemphasize or underutilize amplitude changes, ASPE's balanced weighting strategy captures both the average level and dispersion of data, preserving the overall signal complexity. To validate ASPE's effectiveness, we conducted simulation experiments and applied them to two real-world datasets: an EEG dataset of epileptic seizures and an ECG dataset of arrhythmias. In simulations, ASPE demonstrated superior sensitivity to amplitude changes, outperforming the five existing PE methods in identifying dynamic variations accurately. In the physiological datasets, ASPE distinguished disease states more effectively, accurately identifying seizure phases and arrhythmic patterns. These results highlight ASPE's potential as a robust tool for analyzing physiological data with complex amplitude dynamics, offering a more comprehensive assessment of signal behavior and disease states than the current methods.","PeriodicalId":9974,"journal":{"name":"Chaos","volume":"35 3","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143603930","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Non-trivial generation and transmission of information in electronically designed logistic-map networks. 电子设计的物流地图网络中信息的非平凡生成和传输。

IF 2.7 2区数学

Chaos Pub Date : 2025-03-01 DOI: 10.1063/5.0238711

Caracé Gutiérrez, Cecilia Cabeza, Nicolás Rubido

{"title":"Non-trivial generation and transmission of information in electronically designed logistic-map networks.","authors":"Caracé Gutiérrez, Cecilia Cabeza, Nicolás Rubido","doi":"10.1063/5.0238711","DOIUrl":"https://doi.org/10.1063/5.0238711","url":null,"abstract":"In this work, we carry out a critical analysis of the information generated and transmitted in an electronic implementation of diffusively coupled logistic maps. Our implementation allows one to change the coupling configuration (i.e., the network) and fine-tune the coupling strength and map parameters, but has minimal electronic noise and parameter heterogeneity, which generates collective behaviors that differ from numerical simulations. In particular, we focus on analyzing two dynamical regimes and their dependence on the coupling configuration: one where there is a maximum of information generated and transmitted-corresponding to synchronization of chaotic orbits-and another where information is generated but (practically) not transmitted-corresponding to spatiotemporal chaos. We use Shannon entropy to quantify information generation and mutual information to quantify information transmission. To characterize the two dynamical regimes, we introduce a conditional joint entropy that uses both quantities (entropy and mutual information) and analyze its values for 60 different coupling configurations involving 6 and 12 coupled maps. We find that 90% of the configurations exhibit chaotic synchronization and 92% spatiotemporal chaos, which emerges preceding the chaotic synchronous regime that requires strong coupling strengths. Our results also highlight the coupling configurations that maximize the conditional joint entropy in these regimes without requiring a densely coupled system, which has practical implications (since introducing couplings between units can be costly). Overall, our work contributes to understand the relevance that the network structure has on the generation and transmission of information in complex systems.","PeriodicalId":9974,"journal":{"name":"Chaos","volume":"35 3","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143699851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Interactions of fractional solitons with local defects: Stabilization and scattering. 具有局部缺陷的分数孤子的相互作用：稳定性和散射。

IF 2.7 2区数学

Chaos Pub Date : 2025-03-01 DOI: 10.1063/5.0259305

Thawatchai Mayteevarunyoo, Boris A Malomed

{"title":"Interactions of fractional solitons with local defects: Stabilization and scattering.","authors":"Thawatchai Mayteevarunyoo, Boris A Malomed","doi":"10.1063/5.0259305","DOIUrl":"https://doi.org/10.1063/5.0259305","url":null,"abstract":"Stability is an essential problem in theoretical and experimental studies of solitons in nonlinear media with fractional diffraction, which is represented by the Riesz derivative with Lévy index (LI) α, taking values α<2. Fractional solitons are unstable at α≤1 or α≤2 in uniform one-dimensional media with the cubic or quintic self-focusing, respectively. We demonstrate that, in these cases, the solitons may be effectively stabilized by pinning to a delta-functional trapping potential (attractive defect), which is a relevant setting in optical waveguides with the effective fractional diffraction. Using the respective fractional nonlinear Schrödinger equation with the delta-functional potential term, we find that, in the case of the cubic self-focusing, the fractional solitons are fully stabilized by the pinning to the defect for α=1 and partly stabilized for α<1. In the case of the quintic self-focusing, the full and partial stabilization are found for α=2 and α<2, respectively. In both cases, the instability boundary is exactly predicted by the Vakhitov-Kolokolov criterion. Unstable solitons spontaneously transform into oscillating breathers. A variational approximation (VA) is elaborated parallel to the numerical analysis, with a conclusion that the VA produces accurate results for lower LI values, i.e., stronger fractionality. In the cubic medium, collisions of traveling stable solitons with repulsive and attractive defects are addressed too, demonstrating outcomes in the form of rebound, splitting, and passage.","PeriodicalId":9974,"journal":{"name":"Chaos","volume":"35 3","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143662974","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A minimal model for multigroup adaptive SIS epidemics. 多群体适应性 SIS 流行病的最小模型。

IF 2.7 2区数学

Chaos Pub Date : 2025-03-01 DOI: 10.1063/5.0246228

Massimo A Achterberg, Mattia Sensi, Sara Sottile

{"title":"A minimal model for multigroup adaptive SIS epidemics.","authors":"Massimo A Achterberg, Mattia Sensi, Sara Sottile","doi":"10.1063/5.0246228","DOIUrl":"https://doi.org/10.1063/5.0246228","url":null,"abstract":"We propose a generalization of the adaptive N-Intertwined Mean-Field Approximation (aNIMFA) model studied in Achterberg and Sensi [Nonlinear Dyn. 111, 12657-12670 (2023)] to a heterogeneous network of communities. In particular, the multigroup aNIMFA model describes the impact of both local and global disease awareness on the spread of a disease in a network. We obtain results on the existence and stability of the equilibria of the system, in terms of the basic reproduction number R0. Assuming individuals have no reason to decrease their contacts in the absence of disease, we show that the basic reproduction number R0 is equivalent to the basic reproduction number of the NIMFA model on static networks. Based on numerical simulations, we demonstrate that with just two communities periodic behavior can occur, which contrasts the case with only a single community, in which periodicity was ruled out analytically. We also find that breaking connections between communities is more fruitful compared to breaking connections within communities to reduce the disease outbreak on dense networks, but both strategies are viable in networks with fewer links. Finally, we emphasize that our method of modeling adaptivity is not limited to Susceptible-Infected-Susceptible models, but has huge potential to be applied in other compartmental models in epidemiology.","PeriodicalId":9974,"journal":{"name":"Chaos","volume":"35 3","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143630214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0