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Complexity - Complex Systems Theory
Complex systems present problems both in mathematical modelling and philosophical foundations. The study of complex systems represents a new approach to science that investigates how relationships between parts give rise to the collective behaviors of a system and how the system interacts and forms relationships with its environment. The equations from which models of complex systems are developed generally derive from statistical physics, information theory and non-linear dynamics, and represent organized but unpredictable behaviors of natural systems that are considered fundamentally complex. wikipedia (en)
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Complexity analysis of experimental cardiac arrhythmia

To study the cardiac arrhythmia, an in vitro experimental model and technology Multielectrodes Array (MEA) are used. This platform serves as an intermediary of the electrical activities of cardiac cells and the signal processing / dynamics analysis. Through which the extracellular potential of cardiac cells is acquired, allowing a real-time monitoring / analyzing. Since MEA has 60 electrodes / channels dispatched in a rectangular region, it allows real-time monitoring and signal acquisition on multiple sites. The in vitro experimental model (cardiomyocytes cultures from new-born rats' heart) is directly prepared on the MEA. This carefully prepared culture has similar parameters as cell of human's heart. In order to discriminate the cardiac arrhythmia, complexity analysis methods (Approximate Entropy, ApEn and Sample Entropy, SampEn) are used especially taking into account noises. The results showed that, in case of arrhythmia, the ApEn and SampEn are reduced to about 50\% of the original entropies. Both parameters could be served as factors to discriminate arrhythmia. Moreover, from a point of view of biophysics this decrease 50% of Entropy coincides with the bifurcation (periods, attractors etc.) in case of arrhythmia which have been reported previously. It supports once more the hypothesis that in case of cardiac arrhythmia, the heart entered into chaos which helps better understand the mechanism of atrial fibrillation.

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The Heart as a Complex Adaptive System

The Heart as a Complex Adaptive System | Complexity - Complex Systems Theory | Scoop.it

There is mounting evidence that the heart is a system onto itself and that it is intimately intertwined with the nervous and endocrine system residing within its borders. The capacity of self-organized systems to adapt is embodied in the functional organization of the intrinsic control mechanisms. How these regulatory subsystems communicate and how uncoupling of the hierarchical organization results in loss of adaptive "fitness"remains a challenge in human biology. The principles by which "emergent properties" and functional order of a self-organizingsystem, such as the heart, achieve (homeo)dynamic stability provide a non-reductionist framework for understanding how biological system adapts to imposed internal and external stresses, e.g., ischemia, organ/tissue transplantation. In particular, the newly emergent dynamics of cardiac rhythm observed after the heart is transplanted may reflect a more stable,versatile and adaptive (as per "law of requisite variety") bipartite whole. The integrative action of the living organism can not be gotten from their concatenated fractions but is evolved "relationally", i.e., it emanates from emergent internal requirements of the constitutive parts.

J. Yasha Kresh, Igor Izrailtyan, Andrew S. Wechsler 
Depts. of Cardiothoracic Surgery and Medicine 
MCP-Hahnemann School of Medicine / Drexel University, Philadelphia, PA
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John Symons's curator insight, December 19, 2013 12:23 PM

deeply interesting study of the dynamics of the heart.  

june holley's curator insight, January 7, 8:09 AM

The heart can help us understand self-organization.