deletions | additions       diff --git a/background.md b/background.md  deleted file mode 100644  index aedf6c2..0000000  --- a/background.md  +++ /dev/null 
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**background**  diff --git a/layout.md b/layout.md  index 2e38204..5d12fac 100644  --- a/layout.md  +++ b/layout.md 
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Introduction.md  background.md  results.md  figures/sysred/sysred.png