Why networks?

Abstract

The development of the network concept is prompted by the accumulated quantitative disagreement between the behaviour of single microvessels and the changes of total tissue blood flow, as well as by the ubiquitous flow heterogeneity. It is further driven by the difficulty to attach function-oriented nomenclatures to structural elements of the terminal vascular bed. So far, the efforts of mathematical network modelling have led to a reasonably coherent analysis of microcirculatory hemodynamics from available data on network geometry and blood rheology. These efforts have shown that complete data sets are important because of the non-symmetric architecture of most networks. Due to its effect on exchange efficiency, the relationship between network heterogeneity and total flow regulation remains the currently most relevant physiological problem. So far, the hypothesis of flow heterogeneity being controlled through intra-network communication and consecutive readjustment of flow and flux dispersions is intriguing, but speculative.