Pulse wave velocity (PWV) is a measure of arterial stiffness.he study of the basic scientific principles of the velocity of the pulse wave through the arterial tree dates back to 1808 with the work of Thomas Young.
Put simply, chain migration is a derogatory term used to describe the ability of U.S. citizens and green card holders to bring their extended family into the country. A majority of the roughly one million foreigners who are allowed to enter the U.S. to become permanent residents each year are approved because they're related to Americans.
Migration (human) is the movement of people from one place in the world to another for the purpose of taking up permanent or semipermanent residence, usually across a political boundary. An example of semipermanent residence would be the seasonal movements of migrant farm laborers.eople can either choose to move (voluntary migration) or be forced to move (involuntary migration). Migrations have occurred throughout human history, beginning with the movements of the first human groups from their origins in East Africa to their current location in the world.