Transcranial Doppler (TCD), first described in 1982 [1], is a noninvasive ultrasound (US) study that involves the use of a low-frequency (â¤2 MHz) transducer probe to insonate the basal cerebral arteries through relatively thin bone windows.
Details. as.character and is.character are generic: you can write methods to handle specific classes of objects, see InternalMethods. Further, for as.character the default method calls as.vector, so dispatch is first on methods for as.character and then for methods for as.vector.
Character - the qualities ascribed to a certain man - and thought, according to Aristotle, are the two causes from which actions spring. These elements also determine the success of a given action. Plot, then, is arrangements of incidents (successes or failures) that result from character and thought giving way to action.