$args = array(
		'type' => 'st_ai',
		'child_of' => 0,
		'parent' => '',
		'orderby' => 'name',
		'order' => 'ASC',
		'hide_empty' => 0,
		'hierarchical' => 1,
		'exclude' => '',
		'include' => '',
		'number' => '',
		'taxonomy' => 'st_ai_cat',
		'pad_counts' => false
	);
	
       $categories = get_categories($args);