Purpose The aim of this study was to discuss the advantages of GQI reconstruction in the imaging of nerve fibers at crossing regions. Compared with DTI, the paper also discussed the advantages of GQI in imaging principles. Methods 3-T MRI data from five normal participants were reconstructed using GQI and DTI. After adjusting the parameters, we compared the differences in reconstructed nerve fibers at the crossing regions between the two methods. To complete this study, we chose four obvious examples (the optic nerve, the Superior cerebellar peduncles, the intersection of the pyramidal tract, the corpus callosum and the arcuate fibers and the intersection of the supplementary motor area (SMA) and the anterior part of arcuate fasciculus) to illustrate. Results By reconstructing nerve fibers in three regions, we can find that crossing-area images of nerve fibers significantly differed between DTI and GQI reconstruction. Although crossing fibers could be clearly and completely visualized after GQI reconstruction, they showed artifacts, incompleteness, deletions, and fractures after DTI reconstruction. After GQI reconstruction, we can find that there were two or more nerve fibers in each voxel. However, only one nerve fiber was present in each voxel after DTI reconstruction. Conclusion The imaging of crossing fibers is more complete, consistent, and accurate when they are reconstructed by GQI than when they are reconstructed by DTI.

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A novel method is described for preparing high-quality thin films which exhibit an abrupt resistivity change of 4 - 5 orders of magnitude at about ; this is the best result among those so far prepared on non-crystal substrates. To show the difference from the ordinary sol - gel method which uses vanadium alkoxide as precursor, this method has been called (by the authors) the inorganic sol - gel method, for it uses powder as precursor. This newly developed method shows some advantages in that it produces high-quality thin films (adherent, crack-free, and with good switching properties) in a cheap, simple, and reproducible way. The method consists of four processes: quenching, coating, drying and vacuum heat treatment. These processes show strong effects on the properties of the final films. In this paper, the effects of the drying process on the film blistering and the effects of film thickness, quenching temperature, and heat treatment time on the resistivity switching property were studied, and DSC, XRD, ESCA, and SEM were utilized to study the drying process and characterize the films. It was found that when the drying temperature was and heating rate was in the drying process, the final films would be blister-free and crack-free (on non-crystal substrates). It was also found that the magnitude of resistivity change at the phase transition of the samples treated at for 10 h under a pressure of 0.8 Pa increased with increasing thickness (in the thickness range 0.4 to ). When the film thickness was about , the magnitude of resistivity change of the samples treated under the same conditions was found to decrease with increasing quenching temperature. In a certain range of treatment time the magnitude of resistivity change of the samples treated at under a pressure of 0.8 Pa was found to increase with increasing heat treatment time.

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