//  preload images
picA_off = new Image ()
picA_off.src = "images/main_nav/off_images/picA.jpg"
picA_on = new Image()
picA_on.src = "images/main_nav/on_images/picA.jpg"

picB_off = new Image ()
picB_off.src = "images/main_nav/off_images/picB.jpg"
picB_on = new Image()
picB_on.src = "images/main_nav/on_images/picB.jpg"

picC_off = new Image ()
picC_off.src = "images/main_nav/off_images/picC.jpg"
picC_on = new Image()
picC_on.src = "images/main_nav/on_images/picC.jpg"

picD_off = new Image ()
picD_off.src = "images/main_nav/off_images/picD.jpg"
picD_on = new Image()
picD_on.src = "images/main_nav/on_images/picD.jpg"

picE_off = new Image ()
picE_off.src = "images/main_nav/off_images/picE.jpg"
picE_on = new Image()
picE_on.src = "images/main_nav/on_images/picE.jpg"

picF_off = new Image ()
picF_off.src = "images/main_nav/off_images/picF.jpg"
picF_on = new Image()
picF_on.src = "images/main_nav/on_images/picF.jpg"

function rollOverResearch(){
document.images.research.src = picA_on.src
document.images.research2.src = picC_on.src
}

function rollOutResearch(){
document.images.research.src = picA_off.src
document.images.research2.src = picC_off.src
}

function rollOverTeaching(){
document.images.teaching.src = picB_on.src
document.images.teaching2.src = picE_on.src
}

function rollOutTeaching(){
document.images.teaching.src = picB_off.src
document.images.teaching2.src = picE_off.src
}

function rollOverPatient(){
document.images.patient.src = picF_on.src
document.images.patient2.src = picD_on.src
}

function rollOutPatient(){
document.images.patient.src = picF_off.src
document.images.patient2.src = picD_off.src
}