{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,24]],"date-time":"2026-01-24T17:00:49Z","timestamp":1769274049152,"version":"3.49.0"},"reference-count":51,"publisher":"Springer Science and Business Media LLC","issue":"1-2","license":[{"start":{"date-parts":[[2022,10,7]],"date-time":"2022-10-07T00:00:00Z","timestamp":1665100800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/www.springernature.com\/gp\/researchers\/text-and-data-mining"},{"start":{"date-parts":[[2022,10,7]],"date-time":"2022-10-07T00:00:00Z","timestamp":1665100800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/www.springernature.com\/gp\/researchers\/text-and-data-mining"}],"funder":[{"DOI":"10.13039\/100000001","name":"National Science Foundation","doi-asserted-by":"publisher","award":["1719620"],"award-info":[{"award-number":["1719620"]}],"id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000001","name":"National Science Foundation","doi-asserted-by":"publisher","award":["2009689"],"award-info":[{"award-number":["2009689"]}],"id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["12071332"],"award-info":[{"award-number":["12071332"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Math. Program."],"published-print":{"date-parts":[[2023,9]]},"DOI":"10.1007\/s10107-022-01900-w","type":"journal-article","created":{"date-parts":[[2022,10,7]],"date-time":"2022-10-07T12:04:37Z","timestamp":1665144277000},"page":"97-131","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Trace ratio optimization with an application to multi-view learning"],"prefix":"10.1007","volume":"201","author":[{"given":"Li","family":"Wang","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lei-Hong","family":"Zhang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4388-3398","authenticated-orcid":false,"given":"Ren-Cang","family":"Li","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2022,10,7]]},"reference":[{"key":"1900_CR1","doi-asserted-by":"publisher","DOI":"10.1515\/9781400830244","volume-title":"Optimization Algorithms On Matrix Manifolds","author":"PA Absil","year":"2008","unstructured":"Absil, P.A., Mahony, R., Sepulchre, R.: Optimization Algorithms On Matrix Manifolds. Princeton University Press, Princeton (2008)"},{"key":"1900_CR2","doi-asserted-by":"crossref","unstructured":"Bai, Z., Demmel, J., Dongarra, J., Ruhe, A., van\u00a0der Vorst, H. (eds.): Templates for the solution of Algebraic Eigenvalue Problems: A Practical Guide. SIAM, Philadelphia (2000)","DOI":"10.1137\/1.9780898719581"},{"issue":"1","key":"1900_CR3","doi-asserted-by":"publisher","first-page":"301","DOI":"10.1137\/20M136606X","volume":"43","author":"Z Bai","year":"2022","unstructured":"Bai, Z., Li, R.C., Lu, D.: Sharp estimation of convergence rate for self-consistent field iteration to solve eigenvector-dependent nonlinear eigenvalue problems. SIAM J. Matrix Anal. Appl. 43(1), 301\u2013327 (2022)","journal-title":"SIAM J. Matrix Anal. Appl."},{"issue":"2","key":"1900_CR4","doi-asserted-by":"publisher","first-page":"423","DOI":"10.1109\/TPAMI.2018.2798607","volume":"41","author":"T Baltru\u0161aitis","year":"2018","unstructured":"Baltru\u0161aitis, T., Ahuja, C., Morency, L.P.: Multimodal machine learning: a survey and taxonomy. IEEE Trans. Pattern Anal. Mach. Intell. 41(2), 423\u2013443 (2018)","journal-title":"IEEE Trans. Pattern Anal. Mach. Intell."},{"key":"1900_CR5","doi-asserted-by":"publisher","DOI":"10.1007\/978-1-4612-4768-5","volume-title":"Multidimensional Similarity Structure Analysis","author":"I Borg","year":"1987","unstructured":"Borg, I., Lingoes, J.: Multidimensional Similarity Structure Analysis. Springer, New York (1987)"},{"issue":"3","key":"1900_CR6","doi-asserted-by":"publisher","first-page":"1360","DOI":"10.1137\/17M115935X","volume":"39","author":"Y Cai","year":"2018","unstructured":"Cai, Y., Zhang, L.H., Bai, Z., Li, R.C.: On an eigenvector-dependent nonlinear eigenvalue problem. SIAM J. Matrix Anal. Appl. 39(3), 1360\u20131382 (2018)","journal-title":"SIAM J. Matrix Anal. Appl."},{"issue":"9","key":"1900_CR7","doi-asserted-by":"publisher","first-page":"2542","DOI":"10.1109\/TCYB.2017.2742705","volume":"48","author":"G Cao","year":"2018","unstructured":"Cao, G., Iosifidis, A., Chen, K., Gabbouj, M.: Generalized multi-view embedding for visual recognition and cross-modal retrieval. IEEE Trans. Cybern. 48(9), 2542\u20132555 (2018)","journal-title":"IEEE Trans. Cybern."},{"issue":"4","key":"1900_CR8","doi-asserted-by":"publisher","first-page":"746","DOI":"10.1198\/106186001317243430","volume":"10","author":"MT Chu","year":"2001","unstructured":"Chu, M.T., Trendafilov, N.T.: The orthogonally constrained regression revisited. J. Comput. Graph. Stat. 10(4), 746\u2013771 (2001)","journal-title":"J. Comput. Graph. Stat."},{"key":"1900_CR9","first-page":"2859","volume":"16","author":"JP Cunningham","year":"2015","unstructured":"Cunningham, J.P., Ghahramani, Z.: Linear dimensionality reduction: survey, insights, and generalizations. J. Mach. Learn. Res. 16, 2859\u20132900 (2015)","journal-title":"J. Mach. Learn. Res."},{"key":"1900_CR10","doi-asserted-by":"publisher","DOI":"10.1137\/1.9781611971446","volume-title":"Applied Numerical Linear Algebra","author":"J Demmel","year":"1997","unstructured":"Demmel, J.: Applied Numerical Linear Algebra. SIAM, Philadelphia (1997)"},{"key":"1900_CR11","unstructured":"Dua, D., Graff, C.: UCI machine learning repository (2017). http:\/\/archive.ics.uci.edu\/ml"},{"key":"1900_CR12","first-page":"70","volume":"49","author":"JPV de Geer","year":"1984","unstructured":"de Geer, J.P.V.: Linear relations among $$k$$ sets of variables. Psychometrika 49, 70\u201394 (1984)","journal-title":"Psychometrika"},{"issue":"2","key":"1900_CR13","doi-asserted-by":"publisher","first-page":"303","DOI":"10.1137\/S0895479895290954","volume":"20","author":"A Edelman","year":"1999","unstructured":"Edelman, A., Arias, T.A., Smith, S.T.: The geometry of algorithms with orthogonality constraints. SIAM J. Matrix Anal. Appl. 20(2), 303\u2013353 (1999)","journal-title":"SIAM J. Matrix Anal. Appl."},{"key":"1900_CR14","doi-asserted-by":"publisher","first-page":"599","DOI":"10.1007\/s002110050432","volume":"82","author":"L Eld\u00e9n","year":"1999","unstructured":"Eld\u00e9n, L., Park, H.: A procrustes problem on the Stiefel manifold. Numer. Math. 82, 599\u2013619 (1999)","journal-title":"Numer. Math."},{"key":"1900_CR15","doi-asserted-by":"publisher","DOI":"10.56021\/9781421407944","volume-title":"Matrix Computations","author":"GH Golub","year":"2013","unstructured":"Golub, G.H., Van Loan, C.F.: Matrix Computations, 4th edn. Johns Hopkins University Press, Baltimore (2013)","edition":"4"},{"key":"1900_CR16","doi-asserted-by":"publisher","DOI":"10.1093\/acprof:oso\/9780198510581.001.0001","volume-title":"Procrustes Problems","author":"JC Gower","year":"2004","unstructured":"Gower, J.C., Dijksterhuis, G.B.: Procrustes Problems. Oxford University Press, New York (2004)"},{"key":"1900_CR17","doi-asserted-by":"publisher","DOI":"10.1017\/CBO9780511840371","volume-title":"Topics in Matrix Analysis","author":"RA Horn","year":"1991","unstructured":"Horn, R.A., Johnson, C.R.: Topics in Matrix Analysis. Cambridge University Press, Cambridge (1991)"},{"key":"1900_CR18","doi-asserted-by":"publisher","first-page":"258","DOI":"10.1002\/bs.3830070216","volume":"7","author":"JR Hurley","year":"1962","unstructured":"Hurley, J.R., Cattell, R.B.: The Procrustes program: producing direct rotation to test a hypothesized factor structure. Behav. Sci. 7, 258\u2013262 (1962)","journal-title":"Behav. Sci."},{"key":"1900_CR19","doi-asserted-by":"publisher","first-page":"81","DOI":"10.1007\/s101070050047","volume":"85","author":"C Kanzow","year":"1999","unstructured":"Kanzow, C., Qi, H.D.: A QP-free constrained Newton-type method for variational inequality problems. Math. Program. 85, 81\u2013106 (1999)","journal-title":"Math. Program."},{"key":"1900_CR20","doi-asserted-by":"crossref","unstructured":"Kushmerick, N.: Learning to remove internet advertisements. In: Proceedings of the Third Annual Conference on Autonomous Agents, pp. 175\u2013181 (1999)","DOI":"10.1145\/301136.301186"},{"key":"1900_CR21","doi-asserted-by":"crossref","unstructured":"Lazebnik, S., Schmid, C., Ponce, J.: Beyond bags of features: spatial pyramid matching for recognizing natural scene categories. In: 2006 IEEE Computer Society Conference on Computer Vision and Pattern Recognition (CVPR\u201906), vol.\u00a02, pp. 2169\u20132178. IEEE (2006)","DOI":"10.1109\/CVPR.2006.68"},{"issue":"1","key":"1900_CR22","doi-asserted-by":"publisher","first-page":"59","DOI":"10.1016\/j.cviu.2005.09.012","volume":"106","author":"FF Li","year":"2007","unstructured":"Li, F.F., Fergus, R., Perona, P.: Learning generative visual models from few training examples: An incremental bayesian approach tested on 101 object categories. Comput. Vis. Image Underst. 106(1), 59\u201370 (2007)","journal-title":"Comput. Vis. Image Underst."},{"key":"1900_CR23","doi-asserted-by":"publisher","first-page":"304","DOI":"10.1007\/BF01989752","volume":"33","author":"RC Li","year":"1993","unstructured":"Li, R.C.: A perturbation bound for the generalized polar decomposition. BIT 33, 304\u2013308 (1993)","journal-title":"BIT"},{"key":"1900_CR24","doi-asserted-by":"publisher","first-page":"231","DOI":"10.1090\/S0025-5718-1994-1208838-3","volume":"62","author":"RC Li","year":"1994","unstructured":"Li, R.C.: On perturbations of matrix pencils with real spectra. Math. Comput. 62, 231\u2013265 (1994)","journal-title":"Math. Comput."},{"key":"1900_CR25","doi-asserted-by":"publisher","first-page":"327","DOI":"10.1137\/S0895479893256359","volume":"16","author":"RC Li","year":"1995","unstructured":"Li, R.C.: New perturbation bounds for the unitary polar factor. SIAM J. Matrix Anal. Appl. 16, 327\u2013332 (1995)","journal-title":"SIAM J. Matrix Anal. Appl."},{"key":"1900_CR26","doi-asserted-by":"crossref","unstructured":"Li, R.C.: Rayleigh quotient based optimization methods for eigenvalue problems. In: Bai, Z., Gao, W., Su, Y. (eds.) Matrix Functions and Matrix Equations, Series in Contemporary Applied Mathematics. Lecture summary for 2013 Gene Golub SIAM Summer School vol.\u00a019, pp. 76\u2013108. World Scientific, Singapore (2015)","DOI":"10.1142\/9789814675772_0004"},{"key":"1900_CR27","doi-asserted-by":"publisher","first-page":"1183","DOI":"10.1137\/S0895479801394623","volume":"23","author":"W Li","year":"2002","unstructured":"Li, W., Sun, W.: Perturbation bounds for unitary and subunitary polar factors. SIAM J. Matrix Anal. Appl. 23, 1183\u20131193 (2002)","journal-title":"SIAM J. Matrix Anal. Appl."},{"issue":"4","key":"1900_CR28","doi-asserted-by":"publisher","first-page":"1489","DOI":"10.1137\/15M100883X","volume":"36","author":"XG Liu","year":"2015","unstructured":"Liu, X.G., Wang, X.F., Wang, W.G.: Maximization of matrix trace function of product Stiefel manifolds. SIAM J. Matrix Anal. Appl. 36(4), 1489\u20131506 (2015)","journal-title":"SIAM J. Matrix Anal. Appl."},{"key":"1900_CR29","unstructured":"Lu, D., Li, R.C.: Convergence of SCF for NEPv without unitary invariance property (2022). Work-in-progress"},{"issue":"3","key":"1900_CR30","doi-asserted-by":"publisher","first-page":"553","DOI":"10.1137\/0904038","volume":"4","author":"JJ Mor\u00e9","year":"1983","unstructured":"Mor\u00e9, J.J., Sorensen, D.C.: Computing a trust region step. SIAM J. Sci. Statist. Comput. 4(3), 553\u2013572 (1983)","journal-title":"SIAM J. Sci. Statist. Comput."},{"issue":"5","key":"1900_CR31","doi-asserted-by":"publisher","first-page":"2950","DOI":"10.1137\/090776603","volume":"31","author":"T Ngo","year":"2010","unstructured":"Ngo, T., Bellalij, M., Saad, Y.: The trace ratio optimization problem for dimensionality reduction. SIAM J. Matrix Anal. Appl. 31(5), 2950\u20132971 (2010)","journal-title":"SIAM J. Matrix Anal. Appl."},{"key":"1900_CR32","first-page":"112101:1","volume":"60","author":"F Nie","year":"2017","unstructured":"Nie, F., Zhang, R., Li, X.: A generalized power iteration method for solving quadratic problem on the Stiefel manifold. Sci. China Info. Sci. 60, 112101:1-112101:10 (2017)","journal-title":"Sci. China Info. Sci."},{"issue":"7","key":"1900_CR33","doi-asserted-by":"publisher","first-page":"971","DOI":"10.1109\/TPAMI.2002.1017623","volume":"24","author":"T Ojala","year":"2002","unstructured":"Ojala, T., Pietik\u00e4inen, M., M\u00e4enp\u00e4\u00e4, T.: Multiresolution gray-scale and rotation invariant texture classification with local binary patterns. IEEE Trans. Pattern Anal. Mach. Intell. 24(7), 971\u2013987 (2002)","journal-title":"IEEE Trans. Pattern Anal. Mach. Intell."},{"issue":"3","key":"1900_CR34","doi-asserted-by":"publisher","first-page":"145","DOI":"10.1023\/A:1011139631724","volume":"42","author":"A Oliva","year":"2001","unstructured":"Oliva, A., Torralba, A.: Modeling the shape of the scene: a holistic representation of the spatial envelope. Int. J. Comput. Vis. 42(3), 145\u2013175 (2001)","journal-title":"Int. J. Comput. Vis."},{"issue":"1","key":"1900_CR35","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1145\/3284750","volume":"15","author":"Y Peng","year":"2019","unstructured":"Peng, Y., Qi, J.: CM-GANs: cross-modal generative adversarial networks for common representation learning. ACM Trans. Multimed. Comput. Commun. Appl. (TOMM) 15(1), 1\u201324 (2019)","journal-title":"ACM Trans. Multimed. Comput. Commun. Appl. (TOMM)"},{"key":"1900_CR36","doi-asserted-by":"publisher","DOI":"10.1002\/9780470226797","volume-title":"A Matrix Handbook for Statisticians","author":"GAF Seber","year":"2007","unstructured":"Seber, G.A.F.: A Matrix Handbook for Statisticians. Wiley, New York (2007)"},{"key":"1900_CR37","doi-asserted-by":"crossref","unstructured":"Sharma, A., Kumar, A., Daume, H., Jacobs, D.W.: Generalized multiview analysis: a discriminative latent space. In: 2012 IEEE Conference on Computer Vision and Pattern Recognition, pp. 2160\u20132167. IEEE (2012)","DOI":"10.1109\/CVPR.2012.6247923"},{"key":"1900_CR38","doi-asserted-by":"publisher","DOI":"10.1137\/1.9780898718058","volume-title":"Matrix Algorithms, Vol. II: Eigensystems","author":"GW Stewart","year":"2001","unstructured":"Stewart, G.W.: Matrix Algorithms, Vol. II: Eigensystems. SIAM, Philadelphia (2001)"},{"key":"1900_CR39","volume-title":"Matrix Perturbation Theory","author":"GW Stewart","year":"1990","unstructured":"Stewart, G.W., Sun, J.G.: Matrix Perturbation Theory. Academic Press, Boston (1990)"},{"key":"1900_CR40","unstructured":"Sun, J.G.: Matrix Perturbation Analysis. Academic Press, Beijing (1987). (In Chinese)"},{"issue":"12","key":"1900_CR41","doi-asserted-by":"publisher","first-page":"3272","DOI":"10.1109\/TCYB.2015.2502248","volume":"46","author":"S Sun","year":"2016","unstructured":"Sun, S., Xie, X., Yang, M.: Multiview uncorrelated discriminant analysis. IEEE Trans. Cybern. 46(12), 3272\u20133284 (2016)","journal-title":"IEEE Trans. Cybern."},{"key":"1900_CR42","first-page":"286","volume":"1","author":"J von Neumann","year":"1937","unstructured":"von Neumann, J.: Some matrix-inequalities and metrization of matrix-space. Tomck. Univ. Rev. 1, 286\u2013300 (1937)","journal-title":"Tomck. Univ. Rev."},{"issue":"1","key":"1900_CR43","doi-asserted-by":"publisher","first-page":"139","DOI":"10.1016\/j.neunet.2006.09.011","volume":"20","author":"J V\u00eda","year":"2007","unstructured":"V\u00eda, J., Santamar\u00eda, I., P\u00e9rez, J.: A learning algorithm for adaptive canonical correlation analysis of several data sets. Neural Netw. 20(1), 139\u2013152 (2007)","journal-title":"Neural Netw."},{"key":"1900_CR44","doi-asserted-by":"crossref","unstructured":"Wang, H., Yan, S., Xu, D., Tang, X., Huang, T.: Trace ratio vs. ratio trace for dimensionality reduction. In: 2007 IEEE Conference on Computer Vision and Pattern Recognition, pp. 1\u20138. IEEE (2007)","DOI":"10.1109\/CVPR.2007.382983"},{"key":"1900_CR45","doi-asserted-by":"crossref","unstructured":"Wu, J., Rehg, J.M.: Where am i: Place instance and category recognition using spatial pact. In: 2008 IEEE Conference on Computer Vision and Pattern Recognition, pp. 1\u20138. IEEE (2008)","DOI":"10.1109\/CVPR.2008.4587627"},{"issue":"4","key":"1900_CR46","doi-asserted-by":"publisher","first-page":"1584","DOI":"10.1137\/080720863","volume":"31","author":"LH Zhang","year":"2010","unstructured":"Zhang, L.H., Liao, L.Z., Ng, M.K.: Fast algorithms for the generalized Foley\u2013Sammon discriminant analysis. SIAM J. Matrix Anal. Appl. 31(4), 1584\u20131605 (2010)","journal-title":"SIAM J. Matrix Anal. Appl."},{"issue":"3","key":"1900_CR47","doi-asserted-by":"publisher","first-page":"853","DOI":"10.1007\/s10957-011-9832-4","volume":"157","author":"LH Zhang","year":"2013","unstructured":"Zhang, L.H., Liao, L.Z., Ng, M.K.: Superlinear convergence of a general algorithm for the generalized Foley\u2013Sammon discriminant analysis. J. Optim. Theory Appl. 157(3), 853\u2013865 (2013)","journal-title":"J. Optim. Theory Appl."},{"issue":"2","key":"1900_CR48","doi-asserted-by":"publisher","first-page":"890","DOI":"10.1109\/TPAMI.2020.3012541","volume":"44","author":"LH Zhang","year":"2022","unstructured":"Zhang, L.H., Wang, L., Bai, Z., Li, R.C.: A self-consistent-field iteration for orthogonal canonical correlation analysis. IEEE Trans. Pattern Anal. Mach. Intell. 44(2), 890\u2013904 (2022). https:\/\/doi.org\/10.1109\/TPAMI.2020.3012541","journal-title":"IEEE Trans. Pattern Anal. Mach. Intell."},{"issue":"3","key":"1900_CR49","doi-asserted-by":"publisher","first-page":"957","DOI":"10.1137\/19M1270872","volume":"41","author":"LH Zhang","year":"2020","unstructured":"Zhang, L.H., Yang, W.H., Shen, C., Ying, J.: An eigenvalue-based method for the unbalanced Procrustes problem. SIAM J. Matrix Anal. Appl. 41(3), 957\u2013983 (2020)","journal-title":"SIAM J. Matrix Anal. Appl."},{"issue":"7","key":"1900_CR50","doi-asserted-by":"publisher","first-page":"971","DOI":"10.1007\/s11425-006-0971-2","volume":"49","author":"Z Zhang","year":"2006","unstructured":"Zhang, Z., Du, K.: Successive projection method for solving the unbalanced procrustes problem. Sci. China Math. 49(7), 971\u2013986 (2006)","journal-title":"Sci. China Math."},{"key":"1900_CR51","doi-asserted-by":"publisher","first-page":"200","DOI":"10.1016\/j.neucom.2016.07.037","volume":"216","author":"H Zhao","year":"2016","unstructured":"Zhao, H., Wang, Z., Nie, F.: Orthogonal least squares regression for feature extraction. Neurocomputing 216, 200\u2013207 (2016)","journal-title":"Neurocomputing"}],"container-title":["Mathematical Programming"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s10107-022-01900-w.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/article\/10.1007\/s10107-022-01900-w\/fulltext.html","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s10107-022-01900-w.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,10,5]],"date-time":"2024-10-05T09:39:08Z","timestamp":1728121148000},"score":1,"resource":{"primary":{"URL":"https:\/\/link.springer.com\/10.1007\/s10107-022-01900-w"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,10,7]]},"references-count":51,"journal-issue":{"issue":"1-2","published-print":{"date-parts":[[2023,9]]}},"alternative-id":["1900"],"URL":"https:\/\/doi.org\/10.1007\/s10107-022-01900-w","relation":{},"ISSN":["0025-5610","1436-4646"],"issn-type":[{"value":"0025-5610","type":"print"},{"value":"1436-4646","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,10,7]]},"assertion":[{"value":"11 January 2021","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"19 September 2022","order":2,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"7 October 2022","order":3,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Declaration"}},{"value":"The authors declare that they have no conflict of interest.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Conflict of interest"}}]}}