The present invention provides a modular pallet having a guide channel-defining portion configured for defining at least one guide channel. A first catheter is introduced through the right common femoral artery and used to position a first balloon occluder within the external carotid artery. The apparatus includes an energy storage unit, and a power-electronic unit. The first to third delay lines have thin film heater phase shifters for correcting phase errors involved in fabrication. In selected embodiments, processing an item can include processing the item in accordance with instructions provided by a remote user. More particularly, the present invention relates to a method for identification andor diagnosis of REM sleep loss from blood samples.