Set the bash field separator to newline:

IFS="
"

See what disk and partitions are currently up, then generate commands to re-add the missing disk and partitions, then run them:

for i in `cat /proc/mdstat | grep md | cut -d [ -f1 | sed -e 's/\(md[0-9]\).*\(sd[a-z][0-9]\)/mdadm --add \/dev\/\1 \/dev\/\2/' | sed -e 's/sdb/sda/'`;  do eval $i; done;

TODO: make it determine which disk to add (/dev/sda or /dev/sdb)