diff --git a/main/admin/statistics/index.php b/main/admin/statistics/index.php
index 4624b1587f..d1d0652338 100755
--- a/main/admin/statistics/index.php
+++ b/main/admin/statistics/index.php
@@ -1,6 +1,6 @@
 <?php
-
 /* For licensing terms, see /license.txt */
+
 /**
  * This tool show global Statistics on general platform events
  * @package chamilo.Statistics
@@ -91,10 +91,11 @@ switch ($_REQUEST['report']) {
             )
         );
         $teachers = $students = array();
+        $countInvisible = isset($_GET['count_invisible_courses']) ? $_GET['count_invisible_courses'] : null;
         foreach ($course_categories as $code => $name) {
             $name = str_replace(get_lang('Department'), "", $name);
-            $teachers[$name] = Statistics::count_users(1, $code, $_GET['count_invisible_courses']);
-            $students[$name] = Statistics::count_users(5, $code, $_GET['count_invisible_courses']);
+            $teachers[$name] = Statistics::count_users(1, $code, $countInvisible);
+            $students[$name] = Statistics::count_users(5, $code, $countInvisible);
         }
         // docents for each course category
         Statistics::print_stats(get_lang('Teachers'), $teachers);
diff --git a/main/inc/lib/api.lib.php b/main/inc/lib/api.lib.php
index 271d69ff66..04776cb2dd 100644
--- a/main/inc/lib/api.lib.php
+++ b/main/inc/lib/api.lib.php
@@ -503,6 +503,15 @@ define('SOCIAL_CENTER_PLUGIN', 2);
 define('SOCIAL_RIGHT_PLUGIN', 3);
 define('CUT_GROUP_NAME', 50);
 
+/**
+ * FormValidator Filter
+ */
+define('NO_HTML', 1);
+define('STUDENT_HTML', 2);
+define('TEACHER_HTML', 3);
+define('STUDENT_HTML_FULLPAGE', 4);
+define('TEACHER_HTML_FULLPAGE', 5);
+
 /**
  * Inclusion of internationalization libraries
  */
diff --git a/main/inc/lib/formvalidator/FormValidator.class.php b/main/inc/lib/formvalidator/FormValidator.class.php
index 4bcab8b59a..fb592806f3 100755
--- a/main/inc/lib/formvalidator/FormValidator.class.php
+++ b/main/inc/lib/formvalidator/FormValidator.class.php
@@ -1,15 +1,6 @@
 <?php
 /* For licensing terms, see /license.txt */
 
-/**
- * Filter
- */
-define('NO_HTML', 1);
-define('STUDENT_HTML', 2);
-define('TEACHER_HTML', 3);
-define('STUDENT_HTML_FULLPAGE', 4);
-define('TEACHER_HTML_FULLPAGE', 5);
-
 /**
  * Objects of this class can be used to create/manipulate/validate user input.
  */
@@ -59,7 +50,7 @@ class FormValidator extends HTML_QuickForm
         $form_target = isset($form_data['target']) ? $form_data['target'] : '';
         $form_attributes = isset($form_data['attributes']) ? $form_data['attributes'] : null;
         $form_track_submit = isset($form_data['track_submit']) ? $form_data['track_submit'] : true;
-
+        $reset = null;
         $result = new FormValidator($form_name, $form_method, $form_action, $form_target, $form_attributes, $form_track_submit);
 
         $defaults = array();
diff --git a/main/inc/lib/statistics.lib.php b/main/inc/lib/statistics.lib.php
index 4e246f93d7..8ad623fb3e 100644
--- a/main/inc/lib/statistics.lib.php
+++ b/main/inc/lib/statistics.lib.php
@@ -141,12 +141,11 @@ class Statistics
     static function get_number_of_activities()
     {
         // Database table definitions
-        global $_configuration;
         $track_e_default  = Database :: get_main_table(TABLE_STATISTIC_TRACK_E_DEFAULT);
         $table_user = Database::get_main_table(TABLE_MAIN_USER);
         $access_url_rel_user_table= Database :: get_main_table(TABLE_MAIN_ACCESS_URL_REL_USER);
         $current_url_id = api_get_current_access_url_id();
-        if ($_configuration['multiple_access_urls']) {
+        if (api_is_multiple_url_enabled()) {
             $sql = "SELECT count(default_id) AS total_number_of_items FROM $track_e_default, $table_user user, $access_url_rel_user_table url WHERE default_user_id = user.user_id AND user.user_id=url.user_id AND access_url_id='".$current_url_id."'";
         } else {
             $sql = "SELECT count(default_id) AS total_number_of_items FROM $track_e_default, $table_user user WHERE default_user_id = user.user_id ";
@@ -537,6 +536,9 @@ class Statistics
         $user_table = Database :: get_main_table(TABLE_MAIN_USER);
         $access_url_rel_user_table= Database :: get_main_table(TABLE_MAIN_ACCESS_URL_REL_USER);
         $current_url_id = api_get_current_access_url_id();
+        $url_condition = null;
+        $url_condition2 = null;
+        $table = null;
         if (api_is_multiple_url_enabled()) {
             $url_condition =  ", $access_url_rel_user_table as url WHERE url.user_id=u.user_id AND access_url_id='".$current_url_id."'";
             $url_condition2 = " AND url.user_id=u.user_id AND access_url_id='".$current_url_id."'";
diff --git a/main/inc/lib/zombie/zombie_manager.class.php b/main/inc/lib/zombie/zombie_manager.class.php
index d2bce3d64d..37c4498178 100755
--- a/main/inc/lib/zombie/zombie_manager.class.php
+++ b/main/inc/lib/zombie/zombie_manager.class.php
@@ -1,4 +1,5 @@
 <?php
+/* For licensing terms, see /license.txt */
 
 /**
  * ZombieQuery
@@ -9,7 +10,6 @@
  */
 class ZombieManager
 {
-
     static function last_year()
     {
         $today = time();
@@ -21,7 +21,7 @@ class ZombieManager
 
     /**
      * Returns users whose last login is prior from $ceiling
-     * 
+     *
      * @param int|string $ceiling last login date
      * @param bool $active_only if true returns only active users. Otherwise returns all users.
      * @return ResultSet
@@ -34,38 +34,37 @@ class ZombieManager
         $user_table = Database::get_main_table(TABLE_MAIN_USER);
         $login_table = Database::get_statistic_table(TABLE_STATISTIC_TRACK_E_LOGIN);
 
-        $sql = 'SELECT 
-                    user.user_id, 
-                    user.firstname, 
-                    user.lastname, 
-                    user.username, 
-                    user.auth_source, 
-                    user.email, 
-                    user.status, 
-                    user.registration_date, 
-                    user.active, 
+        $sql = 'SELECT
+                    user.user_id,
+                    user.firstname,
+                    user.lastname,
+                    user.username,
+                    user.auth_source,
+                    user.email,
+                    user.status,
+                    user.registration_date,
+                    user.active,
                     access.login_date';
 
         global $_configuration;
-        if ($_configuration['multiple_access_urls']) {
-
+        if (api_is_multiple_url_enabled()) {
             $access_url_rel_user_table = Database :: get_main_table(TABLE_MAIN_ACCESS_URL_REL_USER);
             $current_url_id = api_get_current_access_url_id();
 
             $sql .= " FROM $user_table as user, $login_table as access, $access_url_rel_user_table as url
-                      WHERE 
-                        access.login_date = (SELECT MAX(a.login_date) 
-                                             FROM $login_table as a 
+                      WHERE
+                        access.login_date = (SELECT MAX(a.login_date)
+                                             FROM $login_table as a
                                              WHERE a.login_user_id = user.user_id
                                              ) AND
                         access.login_date <= '$ceiling' AND
-                        user.user_id = access.login_user_id AND 
+                        user.user_id = access.login_user_id AND
                         url.user_id = user.user_id AND url.access_url_id=$current_url_id";
         } else {
             $sql .= " FROM $user_table as user, $login_table as access
-                      WHERE 
-                        access.login_date = (SELECT MAX(a.login_date) 
-                                             FROM $login_table as a 
+                      WHERE
+                        access.login_date = (SELECT MAX(a.login_date)
+                                             FROM $login_table as a
                                              WHERE a.login_user_id = user.user_id
                                              ) AND
                         access.login_date <= '$ceiling' AND
@@ -91,4 +90,4 @@ class ZombieManager
     }
 
 
-}
\ No newline at end of file
+}