//email sign-up validation 
function validateEmailSignUp(inputElementToValidate)
{       
    var regex = new RegExp("^[\\w-_\.]*[\\w-_\.]\@[\\w]\.+[\\w]+[\\w]$");        
    if (!regex.test(inputElementToValidate.value))
    {	
        alert("Please enter a valid email address");
        inputElementToValidate.focus();
        return false;
    }       
    return true;    
}