Question: when did notre dame go to artificial turf
[{'answer': 'in 2014', 'provenance': [{'wikipedia_id': '1761752', 'title': 'Notre Dame Stadium', 'start_paragraph_id': 2, 'start_character': 289, 'end_paragraph_id': 2, 'end_character': 296, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '1761752', 'title': 'Notre Dame Stadium', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 331, 'bleu_score': 0.838632783915484, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 16237957184268901127}, 'section': 'Section::::Abstract.'}]}]