var articleOffset = 0;

function ChangeArticle(newArticleOffset)
{
	// hide old article
	if($('article-item-' + articleOffset)) { $('article-item-' + articleOffset).hide(); }

	// change offset
	articleOffset = newArticleOffset;

	// check offset
	if(articleOffset < 0) { articleOffset = 4; }
	if(articleOffset > 4) { articleOffset = 0; }

	// show new image
	if($('article-item-' + articleOffset)) { $('article-item-' + articleOffset).show(); }

	return false;
}

function ReloadArticle()
{
	ChangeArticle(articleOffset + 1);
	setTimeout('ReloadArticle()', 30000);
}

Event.observe(window, 'load', function() { 
	setTimeout('ReloadArticle()', 30000);
});