Chemical tracers can be used to assess the simulated circulation in ocean models. Tracers that have been used in this context include tritium, chlorofluorocarbons, natural and bomb-produced radiocarbon, and to a lesser extent, oxygen, silicate, phosphate, isotopes of organic and inorganic carbon compounds, and certain noble gases (e.g., helium and argon). This paper reviews the use of chemical ...

background: vertebrobasilar arterial territory nourishes one-quarter of human brain. it constitutes some vital and strategic parts of the central nervous system. methods: a number of keywords (vertebral, basilar, artery, and territory) were searched in medline (ovid and pubmed) as well as google, proquest, scopus, cochrane library, and science direct online databases. only articles containing a...