<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>0120-419X</journal-id>
<journal-title><![CDATA[Revista Integración]]></journal-title>
<abbrev-journal-title><![CDATA[Integración - UIS]]></abbrev-journal-title>
<issn>0120-419X</issn>
<publisher>
<publisher-name><![CDATA[Universidad Industrial de Santander]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0120-419X2016000200001</article-id>
<article-id pub-id-type="doi">10.18273/revint.v34n2-2016001</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Osillations in seasonal SIR models with saturated treatment]]></article-title>
<article-title xml:lang="es"><![CDATA[Oscilaciones en modelos SIR estacionales con tratamiento saturado]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[GONZÁLEZ-RAMÍREZ]]></surname>
<given-names><![CDATA[L. ROCÍO]]></given-names>
</name>
<xref ref-type="aff" rid="AFF"/>
<xref ref-type="aff" rid="AAF"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[OSUNA]]></surname>
<given-names><![CDATA[OSVALDO]]></given-names>
</name>
<xref ref-type="aff" rid="AFF"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[VILLAVICENCIO-PULIDO]]></surname>
<given-names><![CDATA[GEISER]]></given-names>
</name>
<xref ref-type="aff" rid="AFF"/>
</contrib>
</contrib-group>
<aff id="AF1">
<institution><![CDATA[,Universidad Michoacana de San Nicolás de Hidalgo Instituto de Física y Matemáticas ]]></institution>
<addr-line><![CDATA[Morelia ]]></addr-line>
<country>México</country>
</aff>
<aff id="AF2">
<institution><![CDATA[,Conacyt  ]]></institution>
<addr-line><![CDATA[D.F., México ]]></addr-line>
</aff>
<aff id="AF3">
<institution><![CDATA[,Universidad Autónoma Metropolitana Unidad Lerma Departamento de Ciencias Ambientales ]]></institution>
<addr-line><![CDATA[ Estado de México]]></addr-line>
<country>México</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>12</month>
<year>2016</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>12</month>
<year>2016</year>
</pub-date>
<volume>34</volume>
<numero>2</numero>
<fpage>125</fpage>
<lpage>131</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_arttext&amp;pid=S0120-419X2016000200001&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_abstract&amp;pid=S0120-419X2016000200001&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_pdf&amp;pid=S0120-419X2016000200001&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract In this work, we give some conditions for the existen e of periodic orbits for a Susceptible-Infectious-Recovered (SIR) model with seasonal saturated incidence functions and saturated treatment rate. We use Leray-Schauder degree theory to prove the existence of periodic orbits.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen. En este trabajo presentamos condiciones suficientes para la existencia de soluciones periódicas en modelos epidemiológicos estacionales de tipo SIR con funciones de incidencia y de tratamiento saturados. Utilizamos la teoría de grado de Leray-Schauder para establecer la existencia de órbitas periódicas en tales modelos.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[Leray-Schauder degree]]></kwd>
<kwd lng="en"><![CDATA[SIR models]]></kwd>
<kwd lng="en"><![CDATA[periodic orbits]]></kwd>
<kwd lng="en"><![CDATA[reproductive number]]></kwd>
<kwd lng="es"><![CDATA[Grado de Leray-Schauder]]></kwd>
<kwd lng="es"><![CDATA[modelo SIR]]></kwd>
<kwd lng="es"><![CDATA[órbitas periódicas]]></kwd>
<kwd lng="es"><![CDATA[número reproductivo básico]]></kwd>
</kwd-group>
</article-meta>
</front><body><![CDATA[   <font size="2" face="Verdana">     <p align="left"><b>DOI:</b> <a href="http://dx.doi.org/10.18273/revint.v34n2-2016001" target="_blank">http://dx.doi.org/10.18273/revint.v34n2-2016001</a></p>      <p align="center"><font size="4"><b><i>Osillations in seasonal SIR models with    <br> saturated treatment</i></b></font></p>      <p align="center">L. ROC&Iacute;O GONZ&Aacute;LEZ-RAM&Iacute;REZ<sup>a, b</sup>, OSVALDO OSUNA <sup>a*</sup>,    <br> GEISER VILLAVICENCIO-PULIDO<sup>c</sup></p>      <p align="center"><sup>a</sup> Universidad Michoacana de San Nicol&aacute;s de Hidalgo, Instituto de F&iacute;sica y    <br> Matem&aacute;ticas, Morelia, M&eacute;xico.    <br> <sup>b</sup> Conacyt, D.F., M&eacute;xico.    <br> <sup>c</sup> Universidad Aut&oacute;noma Metropolitana Unidad Lerma, Departamento de Ciencias    ]]></body>
<body><![CDATA[<br> Ambientales, Estado de M&eacute;xico, M&eacute;xico.</p>  <hr>     <p align="justify"><b><i>Abstract</i></b> In this work, we give some conditions for the existen e of periodic orbits for a Susceptible-Infectious-Recovered (SIR) model with seasonal saturated incidence functions and saturated treatment rate. We use Leray-Schauder degree theory to prove the existence of periodic orbits.</p>      <p align="justify"><b><i>Keywords:</i></b> Leray-Schauder degree, SIR models, periodic orbits, reproductive number.    <br> <b><i>MSC2010:</i></b> 37J45, 34C25, 92D30, 34D23.</p>  <hr>      <p align="center"><font size="3"><b><i>Oscilaciones en modelos SIR estacionales con    <br> tratamiento saturado</i></b></font></p>       <p align="justify"><b><i>Resumen.</i></b> En este trabajo presentamos condiciones suficientes para la existencia de soluciones peri&oacute;dicas en modelos epidemiol&oacute;gicos estacionales de tipo SIR con funciones de incidencia y de tratamiento saturados. Utilizamos la teor&iacute;a de grado de Leray-Schauder para establecer la existencia de &oacute;rbitas peri&oacute;dicas en tales modelos.</p>      <p align="justify"><b><i>Palabras clave:</i></b> Grado de Leray-Schauder, modelo SIR, &oacute;rbitas peri&oacute;dicas, n&uacute;mero reproductivo b&aacute;sico.</p>  <hr>      <p align="justify">Texto Completo disponible en <a href ="pdf\rein\v34n2\v34n2a01.pdf" target="_blank">PDF</a></p>  <hr>      <p align="left"><font size="3"><b><i>References</i></b></font></p>      ]]></body>
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