Seismic intensity scales Seismic intensity scales Seismic intensity scales categorize the intensity or severity of ground shaking (quaking) at a given location, such as resulting from an earthquake. They are distinguished from seismic magnitude scales, which measure the magnitude or overall strength of an earthquake. Intensity scales are based on the observed effects of the shaking, such as the degree to which people or animals were alarmed, and the extent and severity of damage to different kinds of structures or natural features. The maximal intensity observed, and the extent of the area where shaking was felt (see isosiesmal map, below), can be used
Natural product and therefore natural products are often used as starting points for drug discovery. Natural product constituents have inspired numerous drug discovery efforts that eventually gained approval as new drugs by the U.S. Food and Drug Administration Indigenous peoples and ancient civilizations experimented with various plant and animal parts to determine what effect they might have. Through trial and error in isolated cases, traditional healers or shamans found some sources to provide therapeutic effect, representing knowledge of a crude drug that was passed down through generations in such practices as traditional Chinese medicine and Ayurveda. Extracts of some natural products led