function optionsCheck(selectbox)
{	
	//HIV
	var region=document.getElementById('region');
        if (selectbox.selectedIndex == "0")
	{ 
		region[7].disabled = true;
	}
	else	{
		region[7].disabled = false;
	}
	if (selectbox.selectedIndex == "1"){
		region[8].disabled = true;
	}
	else{
		region[8].disabled = false;
	}
	
}


function VirusoptionsCheck(selectbox)
{

	// HFV
	var segment=document.getElementById('segmentVirus');
	var groupname=selectbox.options[selectbox.selectedIndex].parentNode.label;
        if (groupname==undefined){
		segment.disabled = true;
        }
	else if (groupname.match(/Arenavir/i)){
		segment.disabled = false;
	        segment.options[1].disabled = true;
	}
	else if (groupname.match(/Bunyavir/i)){
		segment.disabled = false;
		segment.options[0].disabled = false;
		segment.options[1].disabled = false;
	        segment.options[2].disabled = false;
	}
	else {
		segment.disabled = true;
	}
	document.getElementById('virus_name').innerHTML = selectbox.value;
}

function HideModelSelect()
{
        document.getElementById('selectModel').style.display = 'none';
        document.getElementById('selectRef').style.display   = '';
}