1
2
3
4
5
6
7
8
Subject (ZB):
“...anthropogenic emissions...”
9
10
11
Subject (ZB):
“...PET (positron emission tomography)...”
12
13
14
Subject (ZB):
“...emission...”
15
16
17
Subject (ZB):
“...SPECT (single photon emission computer tomography)...”
18
19
20
Subject (ZB):
“...PET (positron emission tomography)...”