( ( Both schedules ) ( ( ( induced ( ( a lack ) ( of synchrony ) ) ) ( between ( ( ( ( the ( subjects ' ) ) ( sleep-wake cycle ) ) and ) ( ( their ( circadian rhythm ) ) ( -LRB- ( ( ( a ( biological pattern ) ) ( based ( on ( ( a cycle ) ( of ( ( approximately 24 ) hours ) ) ) ) ) ) -RRB- ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT Both) (NNS schedules)) (VP (VBN induced) (NP (NP (DT a) (NN lack)) (PP (IN of) (NP (NN synchrony)))) (PP (IN between) (NP (NP (NP (DT the) (NNS subjects) (POS ')) (JJ sleep-wake) (NN cycle)) (CC and) (NP (NP (PRP$ their) (NN circadian) (NN rhythm)) (PRN (-LRB- -LRB-) (NP (NP (DT a) (JJ biological) (NN pattern)) (VP (VBN based) (PP (IN on) (NP (NP (DT a) (NN cycle)) (PP (IN of) (NP (QP (RB approximately) (CD 24)) (NNS hours))))))) (-RRB- -RRB-)))))) (. .)))
Both schedules induced a lack of synchrony between the subjects' sleep-wake cycle and their circadian rhythm (a biological pattern based on a cycle of approximately 24 hours).
(ROOT (S (NP (NP (JJ Regular) (NNS changes)) (PP (IN in) (NP (NN biology) (CC or) (NN behavior))) (SBAR (WHNP (WDT that)) (S (VP (VBP occur) (PP (IN in) (NP (DT a) (CD 24) (NN hour) (NN cycle))))))) (VP (VBP are) (NP (NP (NN part)) (PP (IN of) (NP (DT the) (NN circadian) (NN rhythm))))) (. .)))