public function saveDataItemToRdfItem(Item $qtiItem, core_kernel_classes_Resource $rdfItem)
    {
        $label = mb_substr($rdfItem->getLabel(), 0, 256, 'UTF-8');
        //set the current data lang in the item content to keep the integrity
        if ($qtiItem->hasAttribute('xml:lang') && !empty($qtiItem->getAttributeValue('xml:lang'))) {
            $lang = $qtiItem->getAttributeValue('xml:lang');
        } else {
            $lang = \common_session_SessionManager::getSession()->getDataLanguage();
        }
        $qtiItem->setAttribute('xml:lang', $lang);
        $qtiItem->setAttribute('label', $label);

        $directory = taoItems_models_classes_ItemsService::singleton()->getItemDirectory($rdfItem);
        $success = $directory->getFile(self::QTI_ITEM_FILE)->put($qtiItem->toXML());

        if ($success) {
            $this->getEventManager()->trigger(new ItemUpdatedEvent($rdfItem->getUri()));
        }

        return $success;
    }