Digestive tract (Duodenal bicarbonate transport), Cell biology (Acid/base transport, Intracellular pH regulation, Localization of membrane transport proteins), Cerebral and nervous system (Choroid plexus biology), Kidneys and urinary tract (Renal sodium and bicarbonate transport), Molecular medicine, Physiology (Acid/base physiology, Water and salt metabolism), Scanning and similar forms of examination (Confocal microscopy, Fluorescence microscopy, Immuno-gold electron microscopy, Live cell microscopy)