Bird This pericardial sac is filled with a serous fluid for lubrication. The heart itself is divided into a right and left half, each with an atrium and ventricle. The atrium and ventricles of each side are separated by atrioventricular valves which prevent back flow from one chamber to the next during contraction. Being myogenic, the heart's pace is maintained by pacemaker cells found in the sinoatrial node, located on the right atrium. The sinoatrial node uses calcium to cause a depolarising signal transduction pathway from the atrium through right and left atrioventricular bundle which communicates contraction to the ventricles. The
Node graph architecture Node graph architecture Node graph architecture is a type of software design which builds around modular node components which can be connected to form a graph. Often the software's underlying node graph architecture is also exposed to the end user as a two-dimensional visualization of the node graph. The node graph architecture is popular in the film and computer games industry. There are often many different node types participating in the node graph. For example, in the Nuke Manual they list hundreds of nodes. Each node type performs one specific task. For example, Nuke's Merge node produces an output image