( ( Light ( that ( is ( emitted ( from ( ( electron transitions ) ( in solids ) ) ) ) ) ) ) ( ( is ( called luminescence ) ) . ) )
(ROOT (S (NP (NP (NNP Light)) (SBAR (WHNP (WDT that)) (S (VP (VBZ is) (VP (VBN emitted) (PP (IN from) (NP (NP (NN electron) (NNS transitions)) (PP (IN in) (NP (NNS solids)))))))))) (VP (VBZ is) (VP (VBN called) (S (ADJP (JJ luminescence))))) (. .)))
Light that is emitted from electron transitions in solids is called luminescence .
(ROOT (S (NP (NP (NNP Producing) (NN light)) (PP (IN without) (NP (DT a) (JJ high) (NN temperature)))) (VP (VBZ is) (VP (VBN called) (S (ADJP (JJ luminescence))))) (. .)))