This morning we had one of those power disruptions (the kind that last just long enough to cause you to reset the clock). Now when I restart Nginx I get the error that it can't open the error.log file

/var/log/nginx/error.log failed (13:permission denied)

also get the failure for the configuration file

/var/run/nginx.pid failed (13:permission denied)
configuration file /etc/nginx/nginx.conf test failed



(the syntax for the configuration file is ok)

Before this nginx was running with no problems.
Why am I get these errors and how do I correct them?