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="120"></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: "publications.waset.org",cType: 'non-interactive',cRay: '9135b5d50e18ce6e',cH: 'iou8yCBO_w5ubPCByY2lWQAHrUK2fPf3I5OzAXpCmcE-1739794604-1.2.1.1-zpF25MKhLtCC_qjQIo8WKuy0PmEu8hJDIHSZHjWHrmqNwIQc54oLJJI9k9RKvdtQ',cUPMDTk: "\/abstracts\/search?q=M.%20G.%20Tanga&__cf_chl_tk=wVpNsw646lWRBaJVxgDsHNdVh4dfA_x_47m2kTHb0Kw-1739794604-1.0.1.1-OtBLdpve400uEzEEjGALr1r6civd87v.D3t7WPFEYqw",cFPWv: 'b',cITimeS: '1739794604',cTTimeMs: '1000',cMTimeMs: '120000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "",fa: "\/abstracts\/search?q=M.%20G.%20Tanga&__cf_chl_f_tk=wVpNsw646lWRBaJVxgDsHNdVh4dfA_x_47m2kTHb0Kw-1739794604-1.0.1.1-OtBLdpve400uEzEEjGALr1r6civd87v.D3t7WPFEYqw",md: "Ht9DuFSrQmstXpJhk8_rvvFL6Uf6bU6grnNrqO8szGo-1739794604-1.2.1.1-hTN4cQ.KOBOc.WJuz5JpmjUU21J_b1kcrSIPyhTpNlitwuQzNloeFnOYob.KdDoEXzlAMJsL56.wzkXT2yYlLbJ3njPuu8owUVtg2PRoFsM5mMVlsb3Rdi9f.EYGpEUtcq2DvVjAuK9GjnP6SqeMvqFEih5Y2DrCZDGRQYBRpz6GUVo0ZmPczqy2gHDJcoS6GnsUIyfKuZ6Q2WzetnIa1zA6pjpJknOWD2sKUUKVZuF6idOj3UzSl30K5gu7mSRQyydW0x5IjNPhstDD6_AMlAxOYSfhdwyXSgVLrswpVRaahM7kbVmHu35cCH9rZdHPWf7vtlaWvBGEEGIR.s8xySq8SY1HYqeZ_x7jO2rr5TpNEgztHdLUh3jguNTG0dNLslrdiX45UDo.ioM29GSr743GQHpOkMqWubfASz7TLX2Lc_1tpp3FpBlU55R4PrlJGAdctDBH2YKGtz61HXjBzMX588fWK3shieG0zqSojb1hzXu48nvbKIzPUgea4Lfl_qf56j_LCxVXWXGds.LvcYzmzm_tFFrvhvxTZUnSlEEfd3wSwZ00vi_dK2oCmOPY3CN.D0huzJW00KfkJkBVDLwQR_76B_CewLHgLVKL3vvW8ThqUh2DIKSA8OPnEwa5orfgkovsoGqWm712Gj.qjvQ61BHiitXzTr0Fvvx6i7htdJv802bNQQgW9DvAyQo.dcxueBf1wFKAGMiBYjHingcUW3SbMXuyyxHPhbYx81krxR7ekkh3jItGDZKQI79ZQhPEETCc.5wM4wYHUdGFrobtDs.tLImRSDfW85T88be_Z_LtACsu915qBTEYchoOut50Ys6N9uJb5tvaR81T.zwi0QEZlRWa6wMH5.isxQoIG.N0q6Ef1.xUgXL8oWVbe1ZDR_M_7TnLb7s6h4KWAuxXCCeoF0BXEZqDPMyqPT6YbeIa8FhkaxeNH.8RsGqegBMmQQnbIF2IjxEK3alLB14kYqNW7HP0fSfk91UaYuVfB2MqCI_CxKOx5RVg3Vm2TpARcAEazWre1ONcm2aaOTvzVwaAlBOtGoskER6KxngLwJBqc6f5h0aCPz3.Aualwz2qTCm996a4CFMcSd6n3Rfej_bY1lCyBlQNoQKem6n3ov8WouH3b9qwJdl6PUCD.xqbPhxCwFzk6cUh0kFZHKR5nnebBfRP07.ZEFE31EWEvAO21wN9yzJ9QvhQ_P7laQXAspxT8Vjg_deQt9c1glWXuZ5_a32ugdy_mBSPd8Hm7nFWF2WOY4PntswItRK6geh2R_VMRs5uVV65J_nYelh.KThqpDDK1V49mlE54e_jH1vYxpHFlZOdKMeAoZ70Kkx8pRUtrzPhcOTvngOKD8kKrZjaPXDhwtODUpnybfJJqtkPT9wV.7bGRymh6jf5ZXNe8CttZySW3qa_dYKW_qOKTXypxGiTd5FEadxP.oZyG6frCx_oTM3jlpFR0FmmYT6fPkWdQkDLRZIcvvgzWqvXHa9GNAe.Q5DEB637vb3YpL9xhEvpcQmaOkPh..Z.D4ABDQY7IEvqEPG9YU9BrdLoaEayK230UKbBPwOksnPCQI41XSdqDLWDEuSG053Y9SYEzzE506E1CDXxdMDpW3hxrRMSfeYWELqbNrD9otjXLiHm9MDeVCYXFQB3EUojoq4uvuM5xop6F5EbbqjRaNrX.hQxUDlQoV8S9mreXutfw3u07uHCv50IJmGiJn4fJROdrXHEhMoWz8PsZZ45oanqSmR.IwYOpeiIR.VrDfcrWPWGckIdMxYQO94R9QVmYZ1qY3sfIh_mWZ8J8ceWhzNtV7tDxG6GdCqpToO1qdIqJGHniPWVoVrV4qsGV6MzXUVJRag7FA5uy5GnHPvjr8IuKD0pd2UnV.JMgrEsR9MuZhtVh9gGJgwpAIyCAl_GCbMcJdop0p6wI26CndKQruXT2KJ3AeHBPZM9_ISXN80",mdrd: "3E9OuXT9spfrdZHrZinC_pcr914igwwnSkvZvnVJo7I-1739794604-1.2.1.1-eRnkF8_Zu1Yy1cPTohwwxICH7wHvLtTABmX39HQtMuAY4UHkdRrMn7PfTMjLFdWL18VKChADZJmUIEr2C29P4vSLcn6BgI65v1YEjls5Q.8Q7hgMu0Y0NFE6974utpmRnIvWLV1eHlM31xBiKT8HfJRTI1IEk5ce7Qus06Hp845zWRZuu3ozq52kzhulQjtP7zXwl0ZEXNxSNo22JBWQJEoSQE1MwMj9OH8CnP1ysNdX_WxLbirvOdccjY9bkCX_jBzPwg4hgujG4cng0S2TUsHfrdxF2uEwrs2VRzuTZxeybn65JFluB_Zk9jZs7CbfIM8CBAOqjXL92PjMjwMohOv_yBdtrx9vcqqN5hzGUH9.jEX6s_e7dyy9RcNp_8gq3mI0yIgMOlAn_x3.lf4fGQE0UWMEK_bPiHyMHiTZ4CUqc4bFRuIGCUxHUjySL8lYPQu_Dw4czCghVA1l.6jBUuPl_NLozj8KfpxTOTyOlg.OSVnWk85AW7eGkjvABkdoK_zvB7XtfnsxElopFsie3Bs8_oGxgdOU1mV.3hSokrrZ1at1nSWHW5q7KuVKTI4EcuVk9pOpwHLUUq9FnIWDnfz3vFI9Ow6h0jTEC4qeE9IWL2llvQ1x7yFGtEtGjrusNjTh4F31gOayZ_rKpOpMqK.EB2IvmJ_FWRfoKDtHtBGKqGUsMTJ0jTbWHogjs8masBM1h2Ns.WpHZ.1NK.qszJfIZg7_iFE3aw173A4aRkFsVOyr1zAmERSol0vU6lFS.BylHZcb8.L6dmaZTkZ6mzxy01djVTFXPoaC5REca3bxE0_XmGX3bIU0uQg838ibe.c0ZkYE1EdFUwcPLN1tIIrIYQvdSgCMpFtKLugh2P6eQAhwFtZ7ZajZneoC_81OxqBdzYYp5pGreHdjqnG6LLZTQd01_Zex27UdmiLkbsR28az1Ge8b6xvKm7gy5MRiCDo41OmdKkg7ANcslznW2eVycx3f.dKiF6RS6Df971PnGHV8QT0FbGhpBskuZIU9T9Jer1nKXO54tnDMg_gz6PKEHeyZw43fx4BT.rYA2LGpaqh.TLrGtvvBCJsXQO3B0TxbebniTXMsLcdTfnCfer1QElMxy7mRETua_.CqqMAA4lZnYqc4CS5Lw0Llcwc3oeLeODsbjnJ9uADbO1B2eMDIpuOkT2AcrHlWgGHalbTAe90m9tNbgJlxVkjQ6yUP_K1RpnbBCXN6DqXa5b.BFj3TsTmEjaaCZVZ10Mm.EojpXm3wFsY12Kllr1IesihnM4CGnIMWOr9vjahDjIlXx465i_LlBbJalESpu87rNaL4ukHA4NOLpHV9MgAsei1263aLQWi36hDvJordXUwwwYzMj_zoDlbXzI9iUZ_ikTtPdLtRiR_TOcMnTEbriis5eO9Ruol1xMjOz6aAJoIaANk33E8XaSHEXyNsjCwQyYX01pEjRbclkeha9AwsEwZKSq1O6.koQ_wAwgrD32SJg2gLyaZe_ZEaEVP.unmE1fgZyCgldHFPvcqoG1wodicgf0AJF.xxekj_d68GRCiDJuGBccIgKamYlUjxkx9g7pR6jkLC5XEAsvIuP1bA6FV5i1aRfj1Cnrxch4ZHPcO9_xSJ5k1Dw3XESrv9zJTf1bEKcjanMe6qj74kiPQI4RawJ_Z1efcIoEp2OA9we.x91ERexSF7GhAn3l7LlA.FEJSVOqXmI2IQZdfE5Qu8JE2BYtWdLXJneDbIAI4DB29gA_hFx7usvZzFkfW2aR6t8iCWCbPXI3aylCKntqC8LCfJRZz_7ciXastSYqRAIVdpgO4lxfepkQ1VJq_pEzilm9G7c3Gzaw5OVU3ms_OScIOXtSX86YosV67ppl4qXhYUAXTHv2w2yopsIi_d2gZspA.UjzYafVGbJyHWxa.JOnIEUCUDNHbeU4.MGJtRjgRpdkcWg8nDMBMHpLn58b15vCrq60k59M2f11vXo1wHitQr"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=9135b5d50e18ce6e';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, "\/abstracts\/search?q=M.%20G.%20Tanga&__cf_chl_rt_tk=wVpNsw646lWRBaJVxgDsHNdVh4dfA_x_47m2kTHb0Kw-1739794604-1.0.1.1-OtBLdpve400uEzEEjGALr1r6civd87v.D3t7WPFEYqw" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>