Event.observe(window, "load", function(){
    var options = {
        method:'post',
        onSuccess:topicsUpdate,
        parameters:"",
        evalJSON:true
    };
    new Ajax.Request('./topicsAjax.php', options);
});

function topicsUpdate(httpObj){
    var Items;
    Items = httpObj.responseJSON;
    if(Items){
        if(Items.res == 'success'){
            $("topics").update(Items.html);
        }
    }
}