Sinoatrial nodal artery Sinoatrial nodal artery The sinoatrial nodal artery (or sinuatrial nodal artery or sinoatrial artery) is an artery of the heart which supplies the sinoatrial node, the natural pacemaker center of the heart, and arises from the right coronary artery in around 60% of people. In about 40% of cases, the sinoatrial artery is a branch of the left circumflex coronary artery. In less than 1% of humans, the artery has an anomalous origin directly from the coronary sinus, descending aorta, or distal right coronary artery. In more than 50% of human hearts, the artery actually courses close to the superior
Node 4 Node 4 Node 4, also known as the Docking Hub System (DHS), is a proposed module of the International Space Station (ISS). As of 2011 NASA was considering a 40-month design and development effort for Node 4 that would result in its launch in late 2013. Node 4 would be built using the Node Structural Test Article (STA) and docked to the forward port of the Harmony module. The Structural Test Article was built to facilitate testing of ISS hardware and was intended to become Node 1. However, during construction, structural design flaws were discovered. The under-construction Node 2 was