Experimental systems are being studied by several universities : the Biosphere 2 project at the University of Arizona , the Stockbridge School of Agriculture project ( University of Massachusetts at Amherst ) .
ADJ NOUN AUX AUX VERB ADP ADJ NOUN : DET PROPN NUM NOUN ADP DET PROPN ADP PROPN , DET PROPN PROPN ADP PROPN NOUN ( PROPN ADP PROPN ADP PROPN ) .