if (document.images) {
		var home = new Image;
		var lab = new Image;
		var publications = new Image;
		var vita = new Image;
		var teaching = new Image;
		var hours = new Image;
		var contact = new Image;
		
		var homea = new Image;
		var laba = new Image;
		var publicationsa = new Image;
		var vitaa = new Image;
		var teachinga = new Image;
		var hoursa = new Image;
		var contacta = new Image;

		home.src = "images/home.jpg";
		lab.src = "images/lab.jpg";
		publications.src = "images/publications.jpg";
		vita.src = "images/vita.jpg";
		teaching.src = "images/teaching.jpg";
		hours.src = "images/officehours.jpg";
		contact.src = "images/contact.jpg";

		homea.src = "images/on/home.jpg";
		laba.src = "images/on/lab.jpg";
		publicationsa.src = "images/on/publications.jpg";
		vitaa.src = "images/on/vita.jpg";
		teachinga.src = "images/on/teaching.jpg";
		hoursa.src = "images/on/officehours.jpg";
		contacta.src = "images/on/contact.jpg";

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	function act(imgName) {
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	function inact(imgName) {
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	   document[imgName].src = imgOff;
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