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.
Dynamic Character. Definition of Dynamic Character. Like a round character, a dynamic character also undergoes changes throughout the narrative due to several conflicts he encounters on his journey. A dynamic character faces trials and tribulations and takes time to learn from encounters, other characters, experiences, and mistakes he/she commits.