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A position-sensitive proportional counter (PSPC) for a wavelength-dispersive crystal spectrometer system has been constructed for high-resolution PIKE experiments in atmospheric air. This PSPC has seven resistive wire anodes. Each anode operates as one PSPC. Pulses from the anodes are converted into digital signals with a 512 × 7 channel charge-division analyzer. We can simultaneously obtain seven spectra. A computer software converts this 2D data set into one spectrum after adjusting the offset channels and conversion factors. The spatial resolution of this detector is somewhat larger than that of our single PSPC system previously developed, while its counting efficiency is seven times higher than that of the single one.

Since the cellular metabolism has not yet been fully elucidated, it is very useful to get the information of elemental distributions in a single cell. We applied a micro-PIXE camera to obtain a picture presented with density of an element in a cell. Our micro-PIXE camera is on the basis of PIXE analysis using micro ion beams with the spot size of less than 1 μ m and the samples can be analyzed in air, so the size and the state of samples are not limited. Here, we analyzed the spatial distributions of elements in a single cell of animal for a medical application. Bovine aortic endothelial cells(BAECs) were cultured in culture medium containing bromodeoxyuridine(BrdU) which is known to be used in the DNA synthesis. We could take the elemental maps of phosphorus, potassium and sulfur which present well a shape of cell and a position of nucleus in this cell. Moreover, we obtained the picture of Br, that is, BrdU. It was found that BrdU was locally concentrated in two or three regions in the nucleus.