( ( ( Congress ' ) concern ) ( ( ( ( was ( ( ( ( with scientists ) unknowingly ) and ) ( needlessly ( duplicating ( ( the work ) ( of ( other scientists ) ) ) ) ) ) ) , ) ( not ( with ( replications ( of ( experiments ( to ( ( ( check or ) expand ) ( ( the work ) ( of others ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (NNP Congress) (POS ')) (NN concern)) (VP (VBD was) (UCP (PP (IN with) (NP (NNS scientists)) (ADVP (RB unknowingly))) (CC and) (VP (ADVP (RB needlessly)) (VBG duplicating) (NP (NP (DT the) (NN work)) (PP (IN of) (NP (JJ other) (NNS scientists)))))) (, ,) (PP (RB not) (IN with) (NP (NP (NNS replications)) (PP (IN of) (NP (NNS experiments) (S (VP (TO to) (VP (VB check) (CC or) (VB expand) (NP (NP (DT the) (NN work)) (PP (IN of) (NP (NNS others)))))))))))) (. .)))
Congress' concern was with scientists unknowingly and needlessly duplicating the work of other scientists, not with replications of experiments to check or expand the work of others.
(ROOT (S (S (VP (TO To) (VP (VB confirm) (NP (NP (DT the) (NN work)) (PP (IN of) (NP (DT another) (NN scientist))))))) (, ,) (NP (DT a) (NN scientist)) (VP (MD might) (VP (VB replicate) (NP (PRP$ their) (NN work)))) (. .)))