Adding new variable for the Author Pane (Follow Links)

Here's how to adding new variable for the Author Pane

function template_preprocess_author_pane(&$variables) {

  $variables['user_follow'] = '';
  $uid = $variables['account']->uid;
  $name1 = 'twitter';
  $name2 = 'googleplus';

  $twitter = db_query('SELECT path FROM {follow_links} WHERE uid = :uid and name = :name', array(':uid' => $uid, ':name' => $name1))->fetchField();
  $googleplus = db_query('SELECT path FROM {follow_links} WHERE uid = :uid and name = :name', array(':uid' => $uid, ':name' => $name2))->fetchField();
  
  if (!empty($twitter)) {
     $twitter = ' <a href="' .$twitter. '"><img typeof="foaf:Image" alt="Follow me on Twitter" title="Follow me on Twitter" src="/sites/all/modules/follow/icons/wpzoom26/icon-twitter.png"/></a> ';
     $variables['user_follow'] .= $twitter;
  }

  if (!empty($googleplus)) {
     $google = ' <a rel="author" href="' .$googleplus. '"><img typeof="foaf:Image" alt="Follow me on Google+" title="Follow me on Google+" src="/sites/all/modules/follow/icons/wpzoom26/icon-googleplus.png"/></a> ';
     $variables['user_follow'] .= $google;
  }

}

After that add the following code in author-pane.tpl.php or advanced-forum.naked.author-pane.tpl.php.

<?php /* Follow */ ?>
<?php if (isset($user_follow)): ?>
  <div class="author-pane-line author-follow">
    <?php print $user_follow; ?>
  </div>
<?php endif; ?>

Module used are Follow, Author Pane, and Advanced Forum.