function dispNewsActus(type_na) {
     if (type_na == "news") {
         $('li#news_li').attr('class','selectionnee');
         $('li#actus_li').attr('class','non_selectionnee');
         $('div#blocNews').show();
         $('div#blocActualites').hide();
     }
     else {
         $('li#news_li').attr('class','non_selectionnee');
         $('li#actus_li').attr('class','selectionnee');
         $('div#blocNews').hide();
         $('div#blocActualites').show();
     }
     return false;
}