( AMS ( ( was ( used ( for ( ( the determination ) ( of ( carbon isotopes ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP AMS)) (VP (VBD was) (VP (VBN used) (PP (IN for) (NP (NP (DT the) (NN determination)) (PP (IN of) (NP (NN carbon) (NNS isotopes))))))) (. .)))
AMS was used for the determination of carbon isotopes.
(ROOT (S (NP (NP (NNP Carbon) (CD 14) (NN isotope)) (PP (IN of) (NP (NN carbon)))) (VP (VBZ is) (ADVP (RB typically)) (VP (VBN used) (PP (TO to) (NP (NN date) (JJ ancient) (NNS items))))) (. .)))