{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,6,27]],"date-time":"2025-06-27T08:44:49Z","timestamp":1751013889275,"version":"3.37.3"},"reference-count":73,"publisher":"Springer Science and Business Media LLC","issue":"18","license":[{"start":{"date-parts":[[2022,5,2]],"date-time":"2022-05-02T00:00:00Z","timestamp":1651449600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/www.springer.com\/tdm"},{"start":{"date-parts":[[2022,5,2]],"date-time":"2022-05-02T00:00:00Z","timestamp":1651449600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/www.springer.com\/tdm"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61806185","61802361"],"award-info":[{"award-number":["61806185","61802361"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Technology Innovation and Application Development Project in Chongqing","award":["cstc2019jscx-msxmX0299","cstc2019jscx-gksbX0073"],"award-info":[{"award-number":["cstc2019jscx-msxmX0299","cstc2019jscx-gksbX0073"]}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Neural Comput &amp; Applic"],"published-print":{"date-parts":[[2022,9]]},"DOI":"10.1007\/s00521-022-07272-8","type":"journal-article","created":{"date-parts":[[2022,5,2]],"date-time":"2022-05-02T20:02:28Z","timestamp":1651521748000},"page":"15963-15979","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Ordinal regression with representative feature strengthening for face anti-spoofing"],"prefix":"10.1007","volume":"34","author":[{"given":"Fangling","family":"Jiang","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pengcheng","family":"Liu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiang-Dong","family":"Zhou","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2022,5,2]]},"reference":[{"key":"7272_CR1","unstructured":"Arandjelovic R, Gronat P, Torii A, Pajdla T, Sivic J (2016) In: Proceedings of the IEEE conference on computer vision and pattern recognition, pp 5297\u20135307"},{"key":"7272_CR2","unstructured":"Atoum Y, Liu Y, Jourabloo A, Liu X (2017) In: 2017 IEEE International Joint Conference on Biometrics, IEEE. pp 319\u2013328"},{"key":"7272_CR3","unstructured":"Bao W, Li H, Li N, Jiang W (2009) In: 2009 International Conference on Image Analysis and Signal Processing, IEEE, pp 233\u2013236"},{"issue":"4","key":"7272_CR4","doi-asserted-by":"publisher","first-page":"043007","DOI":"10.1117\/1.JEI.26.4.043007","volume":"26","author":"A Benlamoudi","year":"2017","unstructured":"Benlamoudi A (2017) Face antispoofing based on frame difference and multilevel representation. J Electron Imaging 26(4):043007","journal-title":"J Electron Imaging"},{"key":"7272_CR5","unstructured":"Biometrics IJS (2016) Information technology \u2013 biometric presentation attack detection \u2013 part 1: Framework. International Organization for Standardization 2"},{"issue":"8","key":"7272_CR6","doi-asserted-by":"publisher","first-page":"1818","DOI":"10.1109\/TIFS.2016.2555286","volume":"11","author":"Z Boulkenafet","year":"2016","unstructured":"Boulkenafet Z, Komulainen J, Hadid A (2016) Face spoofing detection using colour texture analysis. IEEE Trans Inf Forensics Secur 11(8):1818\u20131830","journal-title":"IEEE Trans Inf Forensics Secur"},{"issue":"2","key":"7272_CR7","first-page":"141","volume":"24","author":"Z Boulkenafet","year":"2017","unstructured":"Boulkenafet Z, Komulainen J, Hadid A (2017) Face antispoofing using speeded-up robust features and fisher vector encoding. IEEE Signal Process Lett 24(2):141\u2013145","journal-title":"IEEE Signal Process Lett"},{"key":"7272_CR8","unstructured":"Boulkenafet Z, Hadid A (2015) In: 2015 IEEE international conference on image processing (ICIP). IEEE, pp 2636\u20132640"},{"key":"7272_CR9","unstructured":"Boulkenafet Z, Komulainen J, et al (2017) In: 2017 IEEE International Joint Conference on Biometrics (IJCB). IEEE, pp 688\u2013696"},{"key":"7272_CR10","unstructured":"Boulkenafet Z, Komulainen J, Li L, Feng X, Hadid A (2017) In: 2017 12th IEEE International Conference on Automatic Face and Gesture Recognition. IEEE, pp 612\u2013618"},{"key":"7272_CR11","unstructured":"Boureau YL, Ponce J, LeCun Y (2010) In: Proceedings of the 27th international conference on machine learning (ICML-10), pp 111\u2013118"},{"key":"7272_CR12","doi-asserted-by":"publisher","first-page":"937","DOI":"10.1109\/TIFS.2020.3026553","volume":"16","author":"R Cai","year":"2020","unstructured":"Cai R, Li H, Wang S, Chen C, Kot AC (2020) Drl-fas: A novel framework based on deep reinforcement learning for face anti-spoofing. IEEE Trans Inf Forensics Secur 16:937\u2013951","journal-title":"IEEE Trans Inf Forensics Secur"},{"key":"7272_CR13","doi-asserted-by":"publisher","first-page":"578","DOI":"10.1109\/TIFS.2019.2922241","volume":"15","author":"H Chen","year":"2019","unstructured":"Chen H, Hu G, Lei Z, Chen Y, Robertson NM, Li SZ (2019) Attention-based two-stream convolutional networks for face spoofing detection. IEEE Trans Inf Forensics Secur 15:578\u2013593","journal-title":"IEEE Trans Inf Forensics Secur"},{"key":"7272_CR14","unstructured":"Chen S, Zhang C, Dong M, Le J, Rao M (2017) In: Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition, pp 5183\u20135192"},{"key":"7272_CR15","unstructured":"Chingovska I, Anjos A, Marcel S (2012) In: Proceedings of the 11th International Conference of the Biometrics Special Interes Group, EPFL-CONF-192369"},{"key":"7272_CR16","volume-title":"Elements of information theory","author":"TM Cover","year":"1999","unstructured":"Cover TM (1999) Elements of information theory. John Wiley & Sons, New Jersey"},{"key":"7272_CR17","unstructured":"de Freitas Pereira (2013) In: 2013 International Conference on Biometrics (ICB). IEEE, pp 1\u20138"},{"key":"7272_CR18","doi-asserted-by":"crossref","unstructured":"Deb D, Jain AK (2020) Look locally infer globally: A generalizable face anti-spoofing approach. arXiv preprint arXiv:2006.02834","DOI":"10.1109\/TIFS.2020.3029879"},{"issue":"Jul","key":"7272_CR19","first-page":"2121","volume":"12","author":"J Duchi","year":"2011","unstructured":"Duchi J, Hazan E, Singer Y (2011) Adaptive subgradient methods for online learning and stochastic optimization. J Mach Learn Res 12(Jul):2121\u20132159","journal-title":"J Mach Learn Res"},{"key":"7272_CR20","doi-asserted-by":"publisher","first-page":"451","DOI":"10.1016\/j.jvcir.2016.03.019","volume":"38","author":"L Feng","year":"2016","unstructured":"Feng L, Po LM, Li Y, Xu X, Yuan F, Cheung TCH, Cheung KW (2016) Integration of image quality and motion cues for face anti-spoofing: A neural network approach. J Vis Commun Image Represent 38:451\u2013460","journal-title":"J Vis Commun Image Represent"},{"key":"7272_CR21","unstructured":"Feng Y, Wu F, Shao X, Wang Y, Zhou X (2018) In: Proceedings of the European Conference on Computer Vision (ECCV), pp 534\u2013551"},{"key":"7272_CR22","unstructured":"Fu H, Gong M, Wang C, Batmanghelich K, Tao D (2018) In: Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition, pp 2002\u20132011"},{"key":"7272_CR23","doi-asserted-by":"crossref","unstructured":"Gan J, Li S, Zhai Y, Liu C (2017) In: 2017 2nd International Conference on Multimedia and Image Processing (ICMIP), IEEE, pp 1\u20135","DOI":"10.1109\/ICMIP.2017.9"},{"key":"7272_CR24","unstructured":"George A, Marcel S (2019) In: 2019 International Conference on Biometrics (ICB). IEEE, pp 1\u20138"},{"key":"7272_CR25","unstructured":"Granger E, Cardinal P, et al (2020) Deep da for ordinal regression of pain intensity estimation using weakly-labeled videos. arXiv preprint arXiv:2010.15675"},{"key":"7272_CR26","unstructured":"Guo J, Zhu X, Xiao J, Lei Z, Wan G, Li SZ (2019) In: 2019 International Conference on Biometrics (ICB). IEEE, pp 1\u20138"},{"key":"7272_CR27","unstructured":"Y.Z.L.C.X.X.J.Z.J.S.F.Y.W. Haiping Zhu, Hongming Shan (2020) Convolutional ordinal regression forest for image ordinal estimation. arXiv preprint arXiv:2008.03077"},{"key":"7272_CR28","unstructured":"He K, Zhang X, Ren S, Sun J (2016) In: Proceedings of the IEEE conference on computer vision and pattern recognition, pp 770\u2013778"},{"key":"7272_CR29","doi-asserted-by":"crossref","unstructured":"Huang Y, Zhang W, Wang J (2020) Deep frequent spatial temporal learning for face anti-spoofing. arXiv preprint arXiv:2002.03723","DOI":"10.1109\/CVPR42600.2020.00509"},{"key":"7272_CR30","doi-asserted-by":"crossref","unstructured":"Jia S, Li X, Hu C, Guo G, Xu Z (2020) 3d face anti-spoofing with factorized bilinear coding. arXiv preprint arXiv:2005.06514","DOI":"10.1109\/TCSVT.2020.3044986"},{"key":"7272_CR31","doi-asserted-by":"publisher","first-page":"30","DOI":"10.1016\/j.patrec.2019.08.008","volume":"128","author":"F Jiang","year":"2019","unstructured":"Jiang F, Liu P, Zhou X (2019) Multilevel fusing paired visible light and near-infrared spectral images for face anti-spoofing. Pattern Recogn Lett 128:30\u201337","journal-title":"Pattern Recogn Lett"},{"key":"7272_CR32","doi-asserted-by":"crossref","unstructured":"Jourabloo A, Liu Y, Liu X (2018) Face de-spoofing: Anti-spoofing via noise modeling. arXiv preprint arXiv:1807.09968","DOI":"10.1007\/978-3-030-01261-8_18"},{"key":"7272_CR33","unstructured":"Kim T, Kim Y, Kim I, Kim D (2019) In: Proceedings of the IEEE International Conference on Computer Vision Workshops, pp 0\u20130"},{"key":"7272_CR34","unstructured":"Kingma DP, Ba J (2014) Adam: A method for stochastic optimization. arXiv preprint arXiv:1412.6980"},{"issue":"3","key":"7272_CR35","doi-asserted-by":"publisher","first-page":"233","DOI":"10.1016\/j.imavis.2007.05.004","volume":"27","author":"K Kollreider","year":"2009","unstructured":"Kollreider K, Fronthaler H, Bigun J (2009) Non-intrusive liveness detection by face images. Image Vis Comput 27(3):233\u2013244","journal-title":"Image Vis Comput"},{"issue":"11","key":"7272_CR36","doi-asserted-by":"publisher","first-page":"2278","DOI":"10.1109\/5.726791","volume":"86","author":"Y LeCun","year":"1998","unstructured":"LeCun Y, Bottou L, Bengio Y, Haffner P et al (1998) Gradient-based learning applied to document recognition. Proc IEEE 86(11):2278\u20132324","journal-title":"Proc IEEE"},{"issue":"10","key":"7272_CR37","doi-asserted-by":"publisher","first-page":"2639","DOI":"10.1109\/TIFS.2018.2825949","volume":"13","author":"H Li","year":"2018","unstructured":"Li H, He P, Wang S, Rocha A, Jiang X, Kot AC (2018) Learning generalized deep feature representation for face anti-spoofing. IEEE Trans Inf Forensics Secur 13(10):2639\u20132652","journal-title":"IEEE Trans Inf Forensics Secur"},{"issue":"7","key":"7272_CR38","doi-asserted-by":"publisher","first-page":"1794","DOI":"10.1109\/TIFS.2018.2801312","volume":"13","author":"H Li","year":"2018","unstructured":"Li H, Li W, Kot AC (2018) Unsupervised domain adaptation for face anti-spoofing. IEEE Trans Inf Forensics Secur 13(7):1794\u20131809","journal-title":"IEEE Trans Inf Forensics Secur"},{"key":"7272_CR39","unstructured":"Liu Y, Jourabloo A, Liu X (2018) In: Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition, pp 389\u2013398"},{"key":"7272_CR40","unstructured":"Liu A, Tan Z, Li X, Wan J, Escalera S, Guo G, Li SZ (2019)Static and dynamic fusion for multi-modal cross-ethnicity face anti-spoofing. arXiv preprint arXiv:1912.02340"},{"key":"7272_CR41","unstructured":"M\u00e4\u00e4tt\u00e4 J, Hadid A, Pietik\u00e4inen M (2011) In: 2011 international joint conference on Biometrics (IJCB), IEEE, pp 1\u20137"},{"key":"7272_CR42","doi-asserted-by":"crossref","unstructured":"Nagpal C, Dubey SR (2018) A performance evaluation of convolutional neural networks for face anti spoofing. arXiv preprint arXiv:1805.04176","DOI":"10.1109\/IJCNN.2019.8852422"},{"key":"7272_CR43","unstructured":"Niu Z, Zhou M, Wang L, Gao X, Hua G (2016) In: Proceedings of the IEEE conference on computer vision and pattern recognition, pp 4920\u20134928"},{"key":"7272_CR44","unstructured":"Paszke A, Gross S, Massa F, Lerer A, Bradbury J, Chanan G, Killeen T, Lin Z, Gimelshein N, Antiga L, et al (2019) In: Advances in Neural Information Processing Systems, pp 8024\u20138035"},{"issue":"1","key":"7272_CR45","doi-asserted-by":"publisher","first-page":"7","DOI":"10.1109\/TBME.2010.2086456","volume":"58","author":"MZ Poh","year":"2011","unstructured":"Poh MZ, McDuff DJ, Picard RW (2011) Advancements in noncontact, multiparameter physiological measurements using a webcam. IEEE Trans Biomed Eng 58(1):7\u201311","journal-title":"IEEE Trans Biomed Eng"},{"key":"7272_CR46","unstructured":"Raghavendra R, Busch C (2014) In: 2014 17th International Conference on Information Fusion (FUSION). IEEE, pp 1\u20137"},{"key":"7272_CR47","unstructured":"Ruder S (2017) An overview of multi-task learning in deep neural networks. arXiv preprint arXiv:1706.05098"},{"key":"7272_CR48","unstructured":"Selvaraju RR, Cogswell M, Das A, Vedantam R, Parikh D, Batra D (2017) In: Proceedings of the IEEE international conference on computer vision, pp 618\u2013626"},{"key":"7272_CR49","unstructured":"Shao R, Lan X, Li J, Yuen PC (2019) In: Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition, pp 10,023\u201310,031"},{"key":"7272_CR50","doi-asserted-by":"crossref","unstructured":"Shao R, Lan X, Yuen PC (2017) In: 2017 IEEE International Joint Conference on Biometrics (IJCB), IEEE, pp 748\u2013755","DOI":"10.1109\/BTAS.2017.8272765"},{"key":"7272_CR51","unstructured":"Shao R, Perera P, Yuen PC, Patel VM (2020) Federated face anti-spoofing. arXiv preprint arXiv:2005.14638"},{"issue":"99","key":"7272_CR52","first-page":"1","volume":"PP","author":"W Sun","year":"2020","unstructured":"Sun W, Song Y, Huang J, Kot AC (2020) Face spoofing detection based on local ternary label supervision in fully convolutional networks. IEEE Trans Inf Forensics Secur PP(99):1\u20131","journal-title":"IEEE Trans Inf Forensics Secur"},{"key":"7272_CR53","doi-asserted-by":"crossref","unstructured":"Tian Y, Zhang K, Wang L, Sun Z (2020) Face anti-spoofing by learning polarization cues in a real-world scenario. arXiv preprint arXiv:2003.08024","DOI":"10.1145\/3441250.3441254"},{"key":"7272_CR54","unstructured":"Tran D, Bourdev L, Fergus R, Torresani L, Paluri M (2015) In: Proceedings of the IEEE international conference on computer vision, pp 4489\u20134497"},{"key":"7272_CR55","doi-asserted-by":"crossref","unstructured":"Tu X, Fang Y (2017) In: International Conference on Neural Information Processing, Springer, pp 686\u2013695","DOI":"10.1007\/978-3-319-70096-0_70"},{"key":"7272_CR56","doi-asserted-by":"crossref","unstructured":"Tu X, Zhao J, Xie M, Du G, Zhang H, Li J, Ma Z, Feng J (2019) Learning generalizable and identity-discriminative representations for face anti-spoofing. arXiv preprint arXiv:1901.05602","DOI":"10.1145\/3402446"},{"key":"7272_CR57","doi-asserted-by":"publisher","first-page":"332","DOI":"10.1016\/j.jvcir.2017.09.002","volume":"49","author":"Y Wang","year":"2017","unstructured":"Wang Y, Nian F, Li T, Meng Z, Wang K (2017) Robust face anti-spoofing with depth information. J Vis Commun Image Represent 49:332\u2013337","journal-title":"J Vis Commun Image Represent"},{"key":"7272_CR58","doi-asserted-by":"crossref","unstructured":"Wang Z, Yu Z, Zhao C, Zhu X, Qin Y, Zhou Q, Zhou F, Lei Z (2020) Deep spatial gradient and temporal depth learning for face anti-spoofing","DOI":"10.1109\/CVPR42600.2020.00509"},{"key":"7272_CR59","unstructured":"Wang Z, Zhao C, Qin Y, Zhou Q, Qi G, Wan J, Lei Z (2018) Exploiting temporal and depth information for multi-frame face anti-spoofing. arXiv preprint arXiv:1811.05118"},{"issue":"4","key":"7272_CR60","doi-asserted-by":"publisher","first-page":"746","DOI":"10.1109\/TIFS.2015.2400395","volume":"10","author":"D Wen","year":"2015","unstructured":"Wen D, Han H, Jain AK (2015) Face spoof detection with image distortion analysis. IEEE Trans Inf Forensics Secur 10(4):746\u2013761","journal-title":"IEEE Trans Inf Forensics Secur"},{"key":"7272_CR61","unstructured":"Wu J, Yu X, Liu B, Wang Z, Chandraker M (2020) Uncertainty-aware physically-guided proxy tasks for unseen domain face anti-spoofing. arXiv preprint arXiv:2011.14054"},{"key":"7272_CR62","unstructured":"Xu Z, Li S, Deng W (2015) In: 2015 3rd IAPR Asian Conference on Pattern Recognition (ACPR). IEEE, pp 141\u2013145"},{"key":"7272_CR63","first-page":"2","volume":"1","author":"J Yang","year":"2013","unstructured":"Yang J, Lei Z, Liao S, Li SZ (2013) Face liveness detection with component dependent descriptor. ICB 1:2","journal-title":"ICB"},{"key":"7272_CR64","unstructured":"Yang J, Lei Z, Li SZ (2014) Learn convolutional neural network for face anti-spoofing. arXiv preprint arXiv:1408.5601"},{"key":"7272_CR65","unstructured":"Yang X, Luo W, Bao L, Gao Y, Liu W (2020) In: 2019 IEEE\/CVF Conference on Computer Vision and Pattern Recognition (CVPR)"},{"key":"7272_CR66","doi-asserted-by":"crossref","unstructured":"Yi D, Lei Z, Zhang Z, Li SZ (2014) In: Handbook of Biometric Anti-Spoofing, Springer, pp 83\u2013102","DOI":"10.1007\/978-1-4471-6524-8_5"},{"key":"7272_CR67","doi-asserted-by":"crossref","unstructured":"Yu Z, Li X, Niu X, Shi J, Zhao G (2020) In: European Conference on Computer Vision, Springer, pp 557\u2013575","DOI":"10.1007\/978-3-030-58571-6_33"},{"key":"7272_CR68","unstructured":"Yu Z, Qin Y, Li X, Wang Z, Zhao C, Lei Z, Zhao G (2020) In: Proceedings of the IEEE\/CVF Conference on Computer Vision and Pattern Recognition Workshops, pp 650\u2013651"},{"key":"7272_CR69","doi-asserted-by":"crossref","unstructured":"Zhang KY, Yao T, Zhang J, Tai Y, Ding S, Li J, Huang F, Song H, Ma L (2020) In: European Conference on Computer Vision. Springer, pp 641\u2013657","DOI":"10.1007\/978-3-030-58529-7_38"},{"key":"7272_CR70","unstructured":"Zhang Z, Yan J, Liu S, Lei Z, Yi D, Li SZ (2012) In: 2012 5th IAPR international conference on Biometrics (ICB), IEEE, pp 26\u201331"},{"key":"7272_CR71","unstructured":"Zhao J, Cheng Y, Xu Y, Xiong L, Li J, Zhao F, Jayashree K, Pranata S, Shen S, Xing J, et al (2018) In: Proceedings of the IEEE conference on computer vision and pattern recognition, pp 2207\u20132216"},{"key":"7272_CR72","unstructured":"Zhao C, Qin Y, Wang Z, Fu T, Shi H (2019) Meta anti-spoofing: Learning to learn in face anti-spoofing. arXiv preprint arXiv:1904.12490"},{"issue":"2","key":"7272_CR73","first-page":"1","volume":"63","author":"H Zhu","year":"2020","unstructured":"Zhu H, Zhang Y, Li G, Zhang J, Shan H (2020) Ordinal distribution regression for gait-based age estimation. SCIENCE CHINA Inf Sci 63(2):1\u201314","journal-title":"SCIENCE CHINA Inf Sci"}],"container-title":["Neural Computing and Applications"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s00521-022-07272-8.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/article\/10.1007\/s00521-022-07272-8\/fulltext.html","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s00521-022-07272-8.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,9,23]],"date-time":"2024-09-23T16:05:22Z","timestamp":1727107522000},"score":1,"resource":{"primary":{"URL":"https:\/\/link.springer.com\/10.1007\/s00521-022-07272-8"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,5,2]]},"references-count":73,"journal-issue":{"issue":"18","published-print":{"date-parts":[[2022,9]]}},"alternative-id":["7272"],"URL":"https:\/\/doi.org\/10.1007\/s00521-022-07272-8","relation":{},"ISSN":["0941-0643","1433-3058"],"issn-type":[{"type":"print","value":"0941-0643"},{"type":"electronic","value":"1433-3058"}],"subject":[],"published":{"date-parts":[[2022,5,2]]},"assertion":[{"value":"28 December 2021","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"4 April 2022","order":2,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"2 May 2022","order":3,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"The authors declare that they have no conflict of interest.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Conflict of interest"}}]}}