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.
Chiaroscuro is a method of shading which is used to give figures a sense of three-dimensional volume. Tenebrism is where an artist keeps some areas of a painting totally black, allowing one or two areas to be strongly illuminated by comparison. Tenebrism thus allows the artist to control the 'action' in his canvas.