WP Ajax function

function wp_infinitepaginate() {
        $loopFile = $_POST['loop_file'];
        $paged = $_POST['page_no'];
        $author_id = $_POST['author_id'];
        $posts_per_page = get_option('posts_per_page');


        # Load the posts
        query_posts(array(
            'author' => $author_id,
            'paged' => $paged,
            'posts_per_page' => $posts_per_page,
            'post_status' => 'publish',
        ));


        get_template_part($loopFile);
        wp_reset_query();

       exit;
    }

    add_action('wp_ajax_infinite_scroll', 'wp_infinitepaginate');           // for logged in user
    add_action('wp_ajax_nopriv_infinite_scroll', 'wp_infinitepaginate');    // if user not logged in