Myocyte coordinate contraction throughout the remaining heart muscle via the electrical conduction system of the heart. Sinoatrial node activity is modulated, in turn, by nerve fibres of both the sympathetic and parasympathetic nervous systems. These systems act to increase and decrease, respectively, the rate of production of electrical impulses by the sinoatrial node. There are numerous methods employed for fiber-typing, and confusion between the methods is common among non-experts. Two commonly confused methods are histochemical staining for myosin ATPase activity and immunohistochemical staining for Myosin heavy chain (MHC) type. Myosin ATPase activity is commonly—and correctly—referred to as simply "fiber type", and
Node influence metric probabilities. The accessibility has been shown to reveal community structure in urban networks, corresponds to the number of nodes which can be visited in a defined time period, and is predictive of the outcome of epidemiological SIR model spreading processes on networks with large diameter and low density. The expected force measures node influence from an epidemiological perspective. It is the expected value of the force of infection generated by the node after two transmissions. The expected force of a node formula_4 is given by where the sum is taken over the set formula_9 of all possible transmission clusters resulting