CINXE.COM

<!DOCTYPE html><html lang="en-US"><head><title>Just a moment...</title><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><meta http-equiv="X-UA-Compatible" content="IE=Edge"><meta name="robots" content="noindex,nofollow"><meta name="viewport" content="width=device-width,initial-scale=1"><style>*{box-sizing:border-box;margin:0;padding:0}html{line-height:1.15;-webkit-text-size-adjust:100%;color:#313131;font-family:system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica Neue,Arial,Noto Sans,sans-serif,Apple Color Emoji,Segoe UI Emoji,Segoe UI Symbol,Noto Color Emoji}body{display:flex;flex-direction:column;height:100vh;min-height:100vh}.main-content{margin:8rem auto;max-width:60rem;padding-left:1.5rem}@media (width <= 720px){.main-content{margin-top:4rem}}.h2{font-size:1.5rem;font-weight:500;line-height:2.25rem}@media (width <= 720px){.h2{font-size:1.25rem;line-height:1.5rem}}#challenge-error-text{background-image:url(data:image/svg+xml;base64,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);background-repeat:no-repeat;background-size:contain;padding-left:34px}@media (prefers-color-scheme:dark){body{background-color:#222;color:#d9d9d9}}</style><meta http-equiv="refresh" content="390"></head><body class="no-js"><div class="main-wrapper" role="main"><div class="main-content"><noscript><div class="h2"><span id="challenge-error-text">Enable JavaScript and cookies to continue</span></div></noscript></div></div><script>(function(){window._cf_chl_opt={cvId: '3',cZone: "www.journals.uchicago.edu",cType: 'managed',cRay: '8e9ff8049a90496b',cH: 'vPOK0PPaIrsFfaPBObbOjS5UOn9yWhLfeH0fyAmet0o-1732855742-1.2.1.1-FqhG4OW.vQIlvjqS2WsbrS7QvjOG4zUrtbWBGlpl7Qkzb8eb3yqDtoj6LEb7YOmj',cUPMDTk: "\/doi\/10.1086\/350839?__cf_chl_tk=i5YQ16w1r08ctQaxLZDa_Db1W9v4MzWkWjzREDMBA5k-1732855742-1.0.1.1-SlOJxmbjK_cz0Tx9lpC4iL4sLyaoYbUYxTfh7z76Fqo",cFPWv: 'b',cITimeS: '1732855742',cTTimeMs: '1000',cMTimeMs: '390000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "",fa: "\/doi\/10.1086\/350839?__cf_chl_f_tk=i5YQ16w1r08ctQaxLZDa_Db1W9v4MzWkWjzREDMBA5k-1732855742-1.0.1.1-SlOJxmbjK_cz0Tx9lpC4iL4sLyaoYbUYxTfh7z76Fqo",md: "7vRYC33rrR450DsdDeDfmuG5ZEgKmRTld6lDQ87GiDo-1732855742-1.2.1.1-6MlG_YdyAqIJ0Sp45tH2MoT1OOHqwTcqpZ2kdJ4_tK3ZQ2nldon5yQOeOnYmarVFt5noCFhp8Gs6_rrxDNUvre3TgtlbOcISP.EaU5V3kHdfun08ZV6F8uYLhfoTNRfylM0oSYShJ.g0CkA.qrFJPnaWa7sD4CS0xdUmDGxpcovcE8nwhgc1E9rA6kKZQ0ZiuCsWZ8o993mBwvZ_p8RiPgTW_QI6_2uZIhMEECD9n7XpAKhFx9nuqZ3_WU68HdKORH.0vQtTTSt5R6uQ8mtFgTzdlD3U24fspLtKS0y5bBtwopkHvpmGBTvesr3XOQ8RbXcUoAnmM7GZrigt.9B.Vepjmww0Vuxoj120iO0SLy_Fx0FmGjE0HL1lbs2skfkgLnEo6rtjfJZgKZYNfVGEzqc8zrSQQLLwVmkydrZFveKu0PdP3wr5yN594L91d1T15_ufPOKKg1dcA.zBt1rhwgCTRASB4bfy9vEk6UGaspqzpRWooWLjezNE87rqYlB7MRAfRB_yRpR56hoB8scP4bWFqzOa.Jhq3PqDhQbsLyZz4LY9vTq0RFtsdVNeH1mmOy2q8D39sg7cg3M86OrOlM31gxQLfuAyi9kr8NoyafqNnOcOecpoiL0nEMlnObT3hx0Nsna3k.xLfSVQLgCxE4BKRBo05D5Pd9EPYDzkvQZyKOCwhBrIhwyhfo1a_68b5FMNSzKyStI8hXe6dFzUUqcD3EohGZEAuoB33dRbrsAdY_i9eVWw4xSYXqAaXxUArxBSL.I_n_zUQ1_lDTQRDNWt8e_mKWv.rqJRJjXmgWm25hI3pMe28sNiSiJeLePpgBWRiet6JVnEW8Bg1KsFjbhe4KxcH5cZJRkacMKKGsVBzLFkSoXBEJD1gAs6PGYdJp3LHO6Vgitd4zoPM1chZuqpkl8HzMpMd8aZcfgOw_3aq2cKSVMfzUYFjQpxOd_C7QsKeLWEGxM1XkvWF7aV.Jg6MY836dedj.pIYvAv3Wi5Z8Y.Wd.3.ASBRSlr7yb1bOoJop9ApL3oQD29hUjRG_ski2AZkPxYqomtuOSWZp_GydG8Cw0ZjyFjt9PUhowv6vCfe57U.vS4ElfGluhb1u_Kd9meX6.U6BeAvtm1WA05J.h0YUkjsIyT._FGKcnGI.zTqVfLQNUYTIK0gko0jwSMmJ7eJFLMqA_ezWPZiRlaH.Grcyb7gwl2vGVlEteoEBIkgdfLsKn6WZVpXUiSAgJb.4IMv6a578nk0M8bBk_wyv7hEoq5PggzoTGzAQK3T3R2yQZyEGNbycJ5922FvwZLJ7QjhEKvukJRfnSYe7E_k9vYmSfl0kXnx4BTTX.FpRvfIGrKEx_u38f9EH5K.wsmmVlAs8LwY6ntti2GRY01.AWJJwvmiJ5V2kU161yHWkRCJyorH0JDJ6XCNa_YBrngOoz5wLY1OJN.F78IVlxqPrMC_.TccEsfthUk1aNFRnAR_cGt.tgY.SwvMI8cVCFtqV_SQ6hsyMdVtA.C1m051rcKmaz3dmwLVDqTKxpdBLbVZjGbA92aHY8Q9uCX4.2ToDjxT94nEZAh.2WFm.rzADKtR7kIdHsRax1JhewWr2phJBzV50S57hz6ltIHH2NisgiPWd3GezQisSImnVQYGJzUP1AGRZ9v7USL1cyYuf_wHgLWDWEeRM3ngZ2bsUvD342L9rT0m52psQJBSrpkiXA.qACpWS7Mvw.SnkZvjKs1uFt_yc2d3DK_l3x4b15ciZ8ApmPXicuYcOU2HisK1Hu2UqtZPN9nwaogfUYD.3VifTJkBx1DIyXr9udnjPXmNwHT0vLWMzluri_6.wc1M30LqpcY7omxJVMTPPkgiBDVkAT9QfvxdiWi28mFFEtsExS1NZqqzJIkU3WgziLx56YdbxuVzntA0ts027XOc0bMZ2tmPBGDDFwv5G2cWbUx9EXo96rEX93xfQnAbRNVPzPewlelmZw52STRhtNnHLFRnkhPbDC4lym1Jj5Eunrari_ud62mX0.kqjjp8sAYiykTDjoDeUxpsteCpGjYQfAP5t1Q5vKA059KjsFvZpKplcv9YtdW2VYR6A2kJeWDWrOKbYp.65lvyeHDoX._Z50mMdj.VrcO67NT9y9YpIDxfmpHl0r3Q1XgycCTz7CgGY2mowxOrJtktOHiACea3pRgAUIQjGxSyIXCj0AyFZvvtQBvUwvPjjAc5KZ.YAKqdcHi001wkuRAOf54Twsmi0KwV97B4RSj2XQCXXO2s6GaJO42369V3Zy36qDVZ4nQOChQ0UgHl3uvg8sOntQIopRt9VQEV8LjNUvOgc61dnwyL5G00RgNh6k1Ic0_XREd6MO59UIT3cBx7oQySxA0PxGGML3UuIQvxKbvRz_TpaKUdr3tfrNWKqXFbuRj8JfZ2GbRjKrGDj6uhrkwlu3k5ccM.jpSot1qOo56jjZGkcY7DJl5rz5UYscLyiAYRhSMBpXSM58FYxmmaeSn4NpmimRnyr9YttbE_8pntPVgrgDF3aUwt.66nsY3_CmxrHFJEs3kFQz1JTsFr2g.X_QDR1hekjPdoCw9HZTMnMfs4haf91TUNwEHPwjpbtS0Df.r0FeZJSfHTZ7ZNAVNZQ6Ms__5KuhNH19_dT4.lD0am8CObuAp5SZdrIdJgEpo0FZPRwQTwfwAmLjAcOjVwJ45vYSAEU_I_ZwUopktJF2Fw1bqoVUw7Wb2t7.6fskdrzFWCPAGonSwPiofe2at4KioxTyiKDDavUPiF7Bt4ajf_b5gJskmUmYOgnYs_TQWOsiKATy2AE6N8T9x7VFKPR5nitEE4N04Sm5fxk4kzCMRqWtIjps.KzSnofLF1PxwQ.cyo5FfnbMoA4mwKPRe_3dg2cMDEYi7rozAp6iZETNdyh.UVNu9MR.7okUyUu.rWRh987.M3Kyi8sEGO1HKuiCsJSBOoLFKYUPRxKbeG5nEbQ",mdrd: "t7fhNzU1l2GExUW_oO3bOjKcxpO_xnwli8qI93P2Omk-1732855742-1.2.1.1-faNqdGmgudarEUP8hcaVEyNDbIx9PNc2bUf8DwzeBLXKX5NJesocM4phGAFoyIjXpJo26s6N9zo9XzLTasPB7W2QKVvLyi0UPY1KLlAk4TBAGLzEZQLN9xgoXKrnlYfkdbqpTsJyu4kzspjieNSYqO6.KuasyhArbffQRgVPYGT6_FzXcy0OpOqvV.09V_CukC5PyQFNAqVtCJQP7F7vaAnN1hLw0XJk5Of.XG.gel5Pnk3NoFo9kWY9AW9315N9sUjvnBBq7VChcGI8f3QBLdgklFH5v3aoUDkcR4D0eqrxoQA_.22YIWeUmYoLBI2ZBhMRGhc7Oeq7pCh0WDWsXGPJW.5c3YjFMqRFdDrU5dpvWkknv.Ld3_UhzDAXsCZv1gOQeWn0UNkjYgdi0qX7cII0qyo45uBV5JxHmlKUsD93NAlDqK9IeXvx6ZqcjHIeia6A_0gS9P37So7kj9ZQ.LiQVUbeDQBA7QEYkYdxuws0M3HZIKxJFMaIGGzu6DtZHbWkds3ZeT.jS7nQFNbeZmey4ht8i7aKwBNgF8SHRRLGikrXsJsV_KLNaSgqXrisJzYsDO3odhj7lH.G8eTJE_Il2bDlvhJdWXMFF_aB73f6wFQI4EACLbcyRh274OV8Wqn_ISUUHIkicJxum0y9F0PUp76vhmPDNiBk1zypzTrUbs9EqRL1McIo2dmrKeCMTEw6DTZN0y.NQG_NnMM2Iy5mnw.LoypzaLNEXKUhbehYRt2hWeN3L6Wk__mET3zut4LZG6i2twa9uV_zblJ.8UelCE4o4d5OD80MQUihlc0y1l645._dnUVIAKdXPKsl7fxpGfHgxfBo1gZd9IvWdJRS2q3ivu5CQtTr5xZPdH6XuJnPH4LhY1W7b2eFixwyA5ERPE66euLkKyQ9rl_bosKSQT_IRWa3Dv61V4dnFse2RkNRBcwsm6gyWJLjwJxnNyAiKp4OuymmrXznrPQcSftnzdTtUlMvrNlNgYzl.FvBkmloOjEbGJ92VGt1aPFj0RtK7BLi8ciSWb7gAV9YkiaCXBkNLZFTmCUbftBnIwcbOer_UTsRadz0Wtvr5iGUM5O5t7gym5wa4vj5VXx33VfY6XwM30ZLSgUVNUa5FNw548ab_yJON.b1YV28Yb4mMjbhL2.fd.fk5VT8NAWM2pKfvDOMjBgOG2r0mBPK9qiLCUxXAWyaLlYguT6bcFl8a70_ddkQVPe0gA4qnYl7jrrArivgfYc5z9XFbvsYxfskk.vCIodPCygnIf.8FZud5dReFo.t.g1LFzWW4PN_OLKr91gP8blvcKdhJh8B7T3vgYszX93Jk9PqWNEYAE5NQEu2pGT5T6.sRSkwU7EChGtHS3rzowVFweQtfWRUqpTk5rtZpZ9FsWzPLfqK9wB1zZ5RoJepPIqh7QjAcUXiPTExWJgvKJFstZKfovTNX28fY9Qkn1JSTACjXGPI3KpuMPsZcl6PtmPLT9VKqJD4vfM8rcUjy7XJyB8o0HX0.5Fkpggdigb_w3z1EGzB5mHBi_XWMlsjX_wvy0WBMhkkv6KePyNnZraPo3_UbHZNvNui_OF6Yu5oNEWBE38nBXlPAg2fxPlInECRlAb3F6Cg5UbwoLHGL7yQ6kvsly6AiwZDVkuxmNwCCfIl24ozeUUtLFYHr_KNw4P0YecHxJVHwuP_WJCU_H..qxiwtiFluc5kJTroeD_kuIFv2ILoAS70f7yTJDOK1l35rnL9ftAOsbp9p6vCIxZ9GnI2nO1Fnr9LEWvKBq6HDAmZ2UmnHAJykeeeOGMKMtYtPGRi6VY9TZm7iqwUdxg3oE5rxcR8E9EuxQvXh_KCJR9XW.vUBza.ORnvw9LnWQthXeenWQLg34QJuv5M.ANiM0Q9XW49HaTKWnCGrYvJ0_SjU2.haSPoxlLd57qLv.EZj0r36pKc51eGD0LSuAfUx7vIJNHqQ08aDNYM3Loenx.Tuei5az8TEsqXFTQ_CuSX371M.JSRrQ"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=8e9ff8049a90496b';window._cf_chl_opt.cOgUHash = location.hash === '' && location.href.indexOf('#') !== -1 ? '#' : location.hash;window._cf_chl_opt.cOgUQuery = location.search === '' && location.href.slice(0, location.href.length - window._cf_chl_opt.cOgUHash.length).indexOf('?') !== -1 ? '?' : location.search;if (window.history && window.history.replaceState) {var ogU = location.pathname + window._cf_chl_opt.cOgUQuery + window._cf_chl_opt.cOgUHash;history.replaceState(null, null, "\/doi\/10.1086\/350839?__cf_chl_rt_tk=i5YQ16w1r08ctQaxLZDa_Db1W9v4MzWkWjzREDMBA5k-1732855742-1.0.1.1-SlOJxmbjK_cz0Tx9lpC4iL4sLyaoYbUYxTfh7z76Fqo" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>