Pulmonary embolism is the sudden blockage of a major blood vessel (artery) in the lung, usually by a blood clot . In most cases, the clots are small and are not deadly, but they can damage the lung. But if the clot is large and stops blood flow to the lung, it can be deadly.
The term chiaroscuro (from the Italian words chiaro, meaning light, and scuro, meaning dark) refers to the use of light and shade in a work of art to define three-dimensional objects. Masters of this technique were the Italians Leonardo da Vinci and Caravaggio and the Dutch painter Rembrandt.
See  Perspective .. Casein. A milk protein used in paint-making. Chiaroscuro. An Italian word meaning light dark, and referring to the use of gradations of light and shade to create three-dimensional forms in a two-dimensional format. atmospheric perspective.See aerial perspective.balance.tmospheric perspective: Suggesting perspective in a painting with changes in tone and color between foreground and background. The background is usually blurred and hues are less intense.