在通用可激发媒介中,持久的纠旋环
1Department of Ecology and Evolutionary Biology, University of Arizona, Tucson 85721.
Nature
|September 15, 1994
概括
线的乱,而不仅仅是对称的螺旋,是可刺激介质中稳定的特征. 这些在数值研究中观察到的复杂结构预计会出现在各种生物和化学系统中.
科学领域:
- 复杂的系统复杂的系统.
- 非线性动力学是一种非线性动力学.
- 化学动力学 化学动力学
背景情况:
- 在生物系统 (如心肌) 和化学反应 (如贝卢索夫-扎博丁斯基反应) 中发现的可刺激介质,表现出波传播现象.
- 这些媒介中的活动模式通常表现为源自中央的螺旋波.
- 在三维系统中,这些旋流形成线条,可以创建稳定的,可拓分类的结构,如链接和结结的环.
研究的目的:
- 为了研究线在三维可激发介质中的一般配置,超出此前研究的对称结构.
- 为了确定这些线配置在不同条件下的稳定性和强度.
主要方法:
- 一种通用可激发媒介的数值模拟.
- 分析线配置及其稳定性.
- 扰动分析用于测试对参数变化的稳定性.
主要成果:
- 这项研究揭示了,可刺激介质中线的更一般的配置是乱的纠.
- 这种乱的纠配置对系统参数的变化和外部干扰具有坚固的抵抗力.
- 与之前识别的对称结构不同,乱的团代表了一个更普遍,更稳定的组织中心.
结论:
- 线的乱结是三维可激发媒介的稳定和一般特征.
- 由于其固有的稳定性,这些结构预计可以在众多已知的可刺激系统中观察到.
- 这些发现挑战了对称结构的专注,并突出了复杂,动荡的组织的普遍性.
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