Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Intensity values (RGB) calculated from horizontal lines across regions indicated with red bounding boxes in Fig 2. From left to right: Group 1, element 1; group 8, element 2; group 8 element 5 (smallest resolvable); group 8, element 6.
