A answered. Atrial fibrillation can be caused by a number of different things that predispose the heart to arrhythmias. Most commonly, longstanding high blood pressure is the cause. Other causes include heart disease such as blockage in the coronary vessels or diseases such as pneumonia or COPD.
Definition: When an artist deliberately restricts the number of colors they use in a painting, they're said to be using a limited palette. (A palette being what paints are squeezed out onto, ready for use.). Also Known As: Restricted palette.
A ceremonial object, ritually buried. The Palette of Narmer was discovered in 1898 by James Quibell and Frederick Green. It was found with a collection of other objects that had been used for ceremonial purposes and then ritually buried within the temple at Hierakonpolis. Temple caches of this type are not uncommon.