function add() {
		if (!empty($this->data)) {
			$this->Person->create();
			$this->data['Concept'] = array_map(null,$this->data['Concept']['Concept'],$this->data['Concept']['period_id']);
			$this->data['Concept'] = $this->_array_change_key_name(array('concept_id','from_period_id'),$this->data['Concept']);

			if ($this->Person->save($this->data)) {
				$this->Session->setFlash(__('The person has been saved', true));
				$this->redirect(array('action' => 'index'));
			} else {
				$this->Session->setFlash(__('The person could not be saved. Please, try again.', true));
			}
		}
		$roles = $this->Person->Role->find('list');
		$concepts = $this->Person->Concept->find('list');
		$cities = $this->Person->City->find('list');
		$this->set(compact('roles', 'concepts','cities'));
	}

	function edit($id = null) {
		if (!$id && empty($this->data)) {
			$this->Session->setFlash(__('Invalid person', true));
			$this->redirect(array('action' => 'index'));
		}
		if (!empty($this->data)) { //pr($this->data);
			$this->data['Concept'] = array_map(null,$this->data['Concept']['Concept'],$this->data['Concept']['period_id']);
			$this->data['Concept'] = $this->_array_change_key_name(array('concept_id','from_period_id'),$this->data['Concept']);

			if ($this->Person->save($this->data)) {
				$this->Session->setFlash(__('The person has been saved', true));
				$this->redirect(array('action' => 'index'));
			} else {
				$this->Session->setFlash(__('The person could not be saved. Please, try again.', true));
			}
		}
		if (empty($this->data)) {
			$this->data = $this->Person->read(null, $id);
		}

		$i = 0;
		$this->Period->recursive = 0;
		foreach($this->data['Concept'] as $personPeriod) {
			$arr[$i] =  $this->data['Concept'][$i]['ConceptsPerson']['from_period_id'];		//Obtengo un array con los todos los periods_id de las actividades
			$aux[$i] = $this->Period->find('first',array(
								'conditions'=>array('Period.id' => $this->data['Concept'][$i]['ConceptsPerson']['from_period_id'] ),
								'fields' => array('Period.from_date')
									));
			$this->data['Concept'][$i]['ConceptsPerson']['from_date'] = $aux[$i]['Period']['from_date'];
			$i++;
		}

		$periods = json_encode($arr);
		$roles = $this->Person->Role->find('list');
		$concepts = array_values($this->Person->Concept->query('SELECT Concept.id, Concept.description FROM concepts AS Concept
													WHERE Concept.id NOT IN
													    (SELECT conceptpeople.concept_id
													     FROM concepts_people as conceptpeople
													     WHERE (conceptpeople.to_period_id = "0" AND conceptpeople.person_id = "'.$this->data['Person']['id'].'") OR
													     conceptpeople.person_id = "'.$this->data['Person']['id'].'")'));

		$concepts = Set::combine($concepts, '{n}.Concept.id', '{n}.Concept.description');
		$cities = $this->Person->City->find('list');

		$this->set(compact('roles','concepts','cities','periods'));
	}