Hi,
line 15 in author.php is missing a text-domain. The author name should not be translated.
- Old
<h1 class="page-title author"><?php $author = get_the_author(); ?><?php _e('Author Archives: ') ?><span><?php _e("$author") ?></span></h1> - New
<h1 class="page-title author"><?php $author = get_the_author(); ?><?php _e('Author Archives: ', 'thematic'); ?><span><?php echo $author ?></span></h1>
Cheers
