Magnetic resonance imaging (MRI) in patients with multiple sclerosis (MS) has provided major insights into the disease's natural history, and many studies have focussed on possible correlations between MRI findings and the clinical manifestations of MS. In contrast, there are few reports on possible relationships between functional imaging data and cognitive function. The present study assessed the relationship between clinical presentation and combined anatomical and functional imaging data in MS. Twenty patients with definite MS underwent MRI and positron emission tomography (PET) to evaluate cerebral blood flow (rCBF) and oxygen metabolism (rCMRO2). The relationships between these neuroimaging findings and clinical data, including the Expanded Disability Status Scale (EDSS), Mini-mental status scale, Hasegawa Dementia Scale and relapse time, were evaluated with Spearman's rank correlation coefficients. A general reduction in rCBF and rCMRO2 in the gray and white matter were found in the MS patients. EDSS was correlated with the number and size of the lesions on MRI and was negatively correlated with rCMRO2. A correlation between the decrease in rCMRO2 and the level of cognitive impairment was also found. The severity of cerebral hypometabolism was also related to the number of relapses. Morphological and functional findings obtained by MRI and PET are closely related to the clinical status in MS. Our results suggest that measurement of cerebral metabolism in MS has the potential to be an objective marker for monitoring disease activity and to provide prognostic information.

High-quality GaAs films with a dislocation density of 2×106 cm−2 on (100) Si substrates have been obtained by thermal cycle annealing using the metalorganic chemical vapor deposition method. Dislocation behavior in GaAs/Si has been considered. Significant reduction effects of dislocation density in the GaAs layers on Si due to thermal annealing have been analyzed by a simple model, in which annihilation such as coalescence of dislocations is assumed to be caused by dislocation movement under high thermal stress and temperature. Numerical analysis suggests that excellent quality GaAs/Si films with a dislocation density of less than 105 cm−2 will be realized if thermal cycle annealing is carried out more than 1000 times without thermal degradation of the GaAs/Si.

We developed low-resistivity transparent conductive films having the structure of indium-tin-oxide/silver/indium-tin-oxide (ITO/Ag/ITO). The thin silver film was sandwiched by ITO films. Our goal was to study the characteristics of the sandwich films and the display characteristics of simple-matrix liquid-crystal displays (LCDs) fabricated using the sandwich film. The electrical and optical characteristics of the sandwich films depended greatly on the thickness of the ITO and silver layers. Low resistivity and high transmittance were obtained when the film structure had a thickness of ITO/Ag/ITO: 40 nm/15 nm/40 nm. The simple-matrix LCD fabricated using a sandwich of ITO/Ag/ITO exhibited 27%–48% reduction in the level of crosstalk compared to the conventionally available simple-matrix LCDs fabricated using a single-layer ITO film; thus, the display performance was improved.

High quality GaAs films with dislocation densities of less than 1×106 cm−2 on (100) Si substrates have been obtained by selective area growth using the metalorganic chemical vapor deposition method. Remarkable reduction of residual stress and dislocation density in the GaAs layers due to selective area growth have been analyzed using a simple model, in which the assumptions are that the generation of dislocations is caused by thermal stress in the films and dislocation density reduction in GaAs films on Si due to selective growth is caused by stress relief.

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