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: "academic.oup.com",cType: 'interactive',cRay: '928eae40d8778962',cH: '5v1i3kTKwHrfTBR81RIEp7BwM7WD9AW8u4OY.0BZ3ZY-1743411881-1.2.1.1-QHKu0nL4P_ui2a5.tEWT96tMKToPP8IlZPWIng2UKrhrJSwq2jHgo7pDcNoDCZul',cUPMDTk: "\/bbb\/article\/66\/2\/422-425\/5944831?__cf_chl_tk=KpXQTx0EW7Xc7qHlqUdDIlGoEkSucSknQnOFF3lwUic-1743411881-1.0.1.1-ImkN2Rky30nANlKsJ8f3D4wkXm1FzTCTU91FqERlBKc",cFPWv: 'b',cITimeS: '1743411881',cTTimeMs: '1000',cMTimeMs: '390000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "",fa: "\/bbb\/article\/66\/2\/422-425\/5944831?__cf_chl_f_tk=KpXQTx0EW7Xc7qHlqUdDIlGoEkSucSknQnOFF3lwUic-1743411881-1.0.1.1-ImkN2Rky30nANlKsJ8f3D4wkXm1FzTCTU91FqERlBKc",md: "z8cRo1c312vUL69mWKHh0oHJWUNbnG0zh..Jx6YKLRU-1743411881-1.2.1.1-7PGIHeYB.7hJ3jI.zMQbLLLR0b7gpLhTF8Aw83DxkAQwk.H9OlOcA1FVnvBqGMSrjrFbSqeFtGhcjoyKTLctv5chawmZb1daSJUnzehgo_NnIVtTXytfoLBlyVNE.JEyplq_iv2PDVBTUQxi943Q6rQ8Asc9MDJ2TYlv9AllyMj3cniADahKHfV78zgHIjYMWlLH9qDbmsVUWMlIHmu79GlLSDnkgQh31eQCdQ5cKFI0Dj2a0TbnBoITZfBScHeuEsaK9XT6zVLWk1.2u0YRZsjkoIoLpYHp5ntXhE9iuC_7EprCaE8wDCHk6WC6CJJwbAmJO7ZRRiDaCcm45anK2RDwxWZj9Opk2.4FU5FKKX3FOmqHXtzYw6sfeUuLrRSgt4fZNb9llUaw.mz6BumcULiu43vmrD.uh3ZcfD4VeWhe1CEfPVwy4n2__gOrrRTctqtotqQlQIRbhauXhLFrgKkQPSw4fKBSm2n.4S.Kr9y5KYaiY0UsnJZWKzIOeBdbhfPqsDf3RDF5oHYlKjbGUXgCGG6dS5lNA0coxCdOYXj9Dc7dJHMyW2Rnjpfqrw.JwzVnYiAgJrbo3uN4FNAIx0jq_0qLJK5ZYUTVOGINRRUr70qVmZAzIB.N_Yf6hfKzehxPXQawBi00yqFJLTDu4njzyDcDAJ.s100Feg84p2KgqCKPiVHayeh6JkS9c_qC1GSs_hFVQNU3YbR.VKlqLOj70XzwrN6HiAt39jvPrJPCYiiddELG3a1Jg.vlgrI1oBmn0iODM.Zl5uECiLsl3.K5cGXmkRCThy3V6JVSkL5G8UDF4_9_zNYezwR3qp0RKaWwD4DGXsabFefIeU8BzCVOsTw6SpMvbyGu1.RvltBq1_mZel.hIooexgp5WFlIP6w3sdOi7CMpkhqYSDjxTGDa1i3E3nk5AZN.Tx6FSJLJsRsNDVZbmk3WzTrz98hGZ8M3T4MgOU9uxFipI6EHd0leHBwmbtHd0LdJ0o_2MYtQmyeelr0AINXEVaWw7JUDk_w6ctI0rT1ua7B19NBkZDgPEKW6an5bHrnZr7AEaSxph1BWRxTyZX57JC9EeQRhI_Q.K3OgkNqLu_n4E_npG4sVtw5njWhBnTHJPAHnB8gfP1yUUi7a_uj2MgMkPJ4lcUKScfGLmmkY6K1Nqr6ea3MJWK_61NAqDI1URV4MBDfhmJZgvEjxyZyLD954aGqZc1r7YMVVUabAQi1R5aJqn6rCZBA9u5mB5nxryPAHkE8.hyeg0ICWhpQtunwysTASvlWbNcfsHSV56HUZQ0A6Ag",mdrd: "FKOHje_ATFnFrfgbUvknld5gSovS47URTaZyfdl2RHU-1743411881-1.2.1.1-t3mshGyUjZhua4rFbG17FDjM8UaZXy0qCvBqXyYi1oxd.C2wY966PC46PG.P.25_gutkRO3HEz5S2pjEnPEpglcY9Na2B2jZpmcJn5ZpF6Gaa6jLJQtdldbuCpdvHPVAO0AHJQRJnmUbmFZYk7O7fsAyBRaWRR1gsJapcBHOwETY.zGOi8z8ymOAFiVyIun4k6I0QpWmB3FUzhEWcKIcGTT2B3jMWoHt7he30Pwjl3Kg1o0i6Rdq_3TlvfvB064CZ_qZCOg71xrzAGiMRtqKRFObqDXLblFgVmjt7qYMjV_vmYr95UQ42rAT59th1tsx10EZbhDoE7mzPY3OxiR3.VXepvULQJQx1BMghaCOVl8VHxvEBbsTrqgkcu9MHVtFQf0vMZlelGkSh7N3gwgcaenSNqv_qTue6QHSB.sFdaPQuZDOzHhX0MDnD6sWESqQXNMEq3NjKh28ahMvF0FYGUZBSqfM2N7P8_IrcdAr553nXJB_npChg4OT9.vI0zQ6h_IV7h9G1aJpmNXnp1AWMfjCVA0KZLfqCBwh8bZUKFLUpQ9Kx6ge1SZP329wSHRhgS5JYQglJXtskX4xskryqT4_VFEJOn7hLDs.8CCQ51VUVEHsZ6Y5A5oxlfE9miw0a3_5QgJ8CvrBsP1OSjMzKOf_MPvS73SoSUeVbaG8nnXW7Vqw9py12MdzI_mzP95P.bMxg02oCYhR.TolV8vKJDj5kG4.H9dwi5FgsvtZOpzPKBqFFxEzO_nZb.654wL18.6NPIv1nAIuzPZdBP3E4bwAsjNcEBS66NGgeSXl5iCVatk.xpUbea8aJ1.1KnLA34i6.7MB9KppQFDkGS8IYsPpamtdeQRaQrhfbX2PAmrOPQ4VJZXAuLOG_nceZ8Z6skGe4avgPEeRAKcEn5Oi.PlGHeTIoFlUhNv_UIKBon7tTiGCtYF06SD9HRbkAkskC2wPXGlxI1avAdlwRwwHJpjhXjdEGjZZWssi4Bza8.uqLAm5LWciNyAmazVL3wjNzDe15XhM9P_0oFOCTqtcmf9X0Exc_Umr2U3c6HKu9OAHhbB_RwNvF22YTKNisYSNmxOC8PjO1DRWiWftxnMrL2Q_5zE8Ui9Lf94JWTgD6VsjnfoBdp5qX9vgfKFWMPdWwmC7vUJRyRqgW0yC_VXmw6F5mQ0D6kXk1fwQp23V9tUwzyWDeL96KdrJW91ALmTIREuYrmoWNrQ6WF7ekHVXF0e.qwFikz4FLWSLRSsx4s1rFPJmsSai7E8PoosM_cnmU6Z.dDiX_8jewZImnYIXg5rn5R0cOeKpDcbrwaryCm9tVXC8LP6EOocqA4V6NpGA9GV8nbNl8QOymI_Yib6heeyEUcIpYnFd_AKwOkRlnkN_UC_UnffkzrFH1pVCIURLKzbc_BATQdhzI8omF_r2MsHMIJGRy1A3O3phrdUmPik_xFH8r7w.xQSw7TupCuFZKhRNdJv05MxrrLCLqO.TFG3yQGZr5kW.HsNSF7FMeh7CXrD3qHO933vMvXAvBvXXAcv3nDUeb7ACQiOUB.9n7pend8DIiXLZzdxj9wyVFttFiM1FmphF8cN3uuJq8PwaXTZu1TzznQz08g6KI6eHcfge8HiB5h0TQWdkIj6wrSrIbDdn.PB0dCD7W0jq9FAaSgUHUXUK_KBRJNPapNekOEYwPPupE5HNUP67Fspc3D0otfSDU11R0VFcz3ObpdqiRVcX9pNri2mzJvqzUFcbrcafbxuLkaf_8gcLaRI2V2b56m_O9Jj92vBjAYY7AcjdR6m1DZjluiyUjjYNBsHuHq2Me4.yYzi6R49YFkw0yB2i1UpdVoBALQO.mpwvzUoHDoh8Uc9.LBSXRuXTydVmYaYGTVrnRmViyPqVIcdCrQV7gdu0Y_oRAVf25jd1OqG5NMiUrdFYN1BfLALWPqwcrtPVxrJpSBXIR949VVC1f3lMWvmyWLXO7pE3M1ntJmWi_CTWrZWPg7_TFrVwOJzgIdliiElHMkS6o.WCWFghyGkn4sOq.Sal7fBJQX4fuMxuMncOQvALBRSQDlRcmmfdxg"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=928eae40d8778962';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, "\/bbb\/article\/66\/2\/422-425\/5944831?__cf_chl_rt_tk=KpXQTx0EW7Xc7qHlqUdDIlGoEkSucSknQnOFF3lwUic-1743411881-1.0.1.1-ImkN2Rky30nANlKsJ8f3D4wkXm1FzTCTU91FqERlBKc" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>