Sinoatrial node produced an increased heart rate whereas an inferior shift (i.e. the cell producing the fastest action potential within the SA node is further down than previously) produced a decreased heart rate. Sinus node dysfunction describes an irregular heartbeat caused by faulty electrical signals of the heart. When the heart's sinoatrial node is defective, the heart’s rhythms become abnormal – typically too slow or exhibiting pauses in its function or a combination, and very rarely faster than normal. Blockage of the arterial blood supply to the SA node (most commonly due to a myocardial infarction or progressive coronary artery disease) can
Node graph architecture in which a number of input images have been layered. By connecting many different node types together complex image effects can be produced. The node graph architecture often allows grouping of nodes inside other group nodes. This hides complexity inside of the group nodes, and limits their coupling with other nodes outside the group. This leads to a hierarchy where smaller graphs are embedded in group nodes. In Nuke the group node is simply called the Group node. In the paper Hierarchical Small Worlds in Software Architecture they argue that most large software systems are built in a modular and