12 Key and Core Catalog With a mechanical key system, the level of security is determined by masterkey control. A masterkey system enables facilities of any size to manage the building by defining access by person and by area in increasing levels of complexity. Since BEST invented the standard for masterkey systems, there is no
When they occur in the upper part of the aorta, they are called thoracic aortic aneurysms. Aneurysms can occur anywhere in the thoracic aorta, including the ascending aorta near the heart, the aortic arch in the curve of the thoracic aorta and the descending aorta in the lower part of the thoracic aorta.
The aorta is the main artery which arises from the heart and passes through the thorax (chest) and abdomen to carry oxygenated blood from the heart to other parts of the body. 1  Abdominal aortic aneurysm is an aneurysm occurring in the abdominal portion of the aorta.hen an arterial wall is damaged or injured due to any cause, the force exerted by the blood within the artery can easily push out the weakened wall and form an aneurysm. This may occur due to 1  : Old age. 2  Hypertension â high blood pressure.