Rails (RoR) app not working

myappname = My app rsrs

upstream app_server { server unix:/var/run/unicorn.sock fail_timeout=0; }

server { listen 80; root /home/rails/myappname/public; server_name _; index index.htm index.html;

location / {
        try_files $uri/index.html $uri.html $uri @app;
}

location ~* ^.+\.(jpg|jpeg|gif|png|ico|zip|tgz|gz|rar|bz2|doc|xls|exe|pdf|p$
                try_files $uri @app;
        }

 location @app {
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header Host $http_host;
        proxy_redirect off;
        proxy_pass http://app_server;
}

}