test
node1
BFO:0000002
continuant
node1->node1
node2
BFO:0000020
specifically
dependent continuant
node1->node2
node5
BFO:0000019
quality
node2->node5
node2->node2
node4
PATO:0000001
quality
node2->node4
node3
BFO:0000001
entity
node3->node1
node6
PATO:0001241
physical object
quality
node4->node6
node5->node5
node5->node6
node7
PATO:0001018
physical quality
node6->node7
node8
PATO:0001019
mass density
node7->node8