Quantitative Evaluation of Saccadic Eye Movement Disorders Under Random Visual Stimuli on CRT

A computer aided saccadic disorder examination system for clinical use is presented. Eye movements are stimulated by an M-sequence-controlled moving target on a CRT and the degree of saccadic disorder is evaluated by estimating a linear discriminant function, via procedures of cross-correlation analysis and age compensation.     

Crazelike features in deformation of hard elastic poly(4-methyl-1-pentene) film

A hard elastic film of poly(4-methyl-1-pentene) was investigated by using wide-angle X-ray diffraction, small-angle X-ray scattering (SAXS), and stress–strain measurements. The film showed somewhat hard elasticity above the glass transition temperature (T_g), while it showed a brittle nature below T_g. In the former case, the SAXS pattern of the stretched film was very analogous to that of usual crazed materials (crazelike feature), namely void scattering on the meridian and interference scattering due to microfibrils on the equator. The fibrillation was discussed in terms of deformability of the lamellae and, further, that of the hellcal chain. Our results were also compared with the model of ?a?kovi? and Hosemann for deformation of hard elastic crystalline materials.     

Electrolytic hydrogenation of phenols in aqueous acid solutions

On platinum electrodes, may substituted phenols are electrolytically hydrogenated to form corresponding cyclohexanols with a 100% current efficiency on a platinum electrode in aqueous acid solutions. The reaction mechanism was concluded to be the surface reaction between adsorbed phenols and hydrogen. Studies on the substituent effect showed that the hydrogenation is most favoured for unsubstituted phenol, suggesting that the polarity of adsorbed hydrogen atoms are essentially neutral.     

Structural analyses of barbaloin-related compounds in aloe drinks

Four kinds of barbaloin (BA)-related compounds (A, B, C, D) in aloe drinks were isolated by using preparative HPLC. LC/MS analyses of these compounds showed the identical quasimolecular ion peak at m/z 833 [M-H]-. The chemical structures were mainly determined by NMR, including 1H-1H two-dimensional correlation spectroscopy (COSY), nuclear Overhauser and exchange spectroscopy (NOESY), heteronuclear multiple quantum coherence (HMQC), and heteronuclear multiple-bond connectivity (HMBC) experiments. They were identified as BA-related compounds A (10R, 10"S), B (10S, 10"S), C (10S, 10"R), and D (10R, 10"R) coupled through a C-10 to C-7' linkage, and newly found in nature. These results suggested that BA is converted to dimers during storage of aloe drinks.     

Estimation of chlorophyll concentration in lakes and inland seas with a field spectroradiometer above the water surface

The estimation of chlorophyll concentration in the water by use of a field spectroradiometer above the water surface is necessary for the removal of the effect of specular reflection at the water surface. The amount of specular reflection from the water surface was assessed on the basis of the spectral signature data that was measured above and below the water surface. Furthermore, a method to remove the effect of specular reflection from spectral signature data that was measured above water surface was proposed. Finally, chlorophyll-a concentration was estimated accurately from the spectral signature measured by field spectroradiometer above water surface with the proposed surface reflection model.     

Accumulation of L-cystathionine by an Escherichia coli mutant deficient in cystathionine beta-lyase

An Escherichia coli mutant deficient in cystathionine beta-lyase was found to accumulate a substance detectable by ninhydrin reaction and chloride platinic acid reaction in its cells (rarely in the culture supernatant) when cultured with a limited amount (50-200 microg/ml) of L-methionine to support the growth. The product was released by freezing treatment and isolated by ion-exchange chromatography (cation exchange resin: Daiaion SK1B). It was identified as L-cystathionine by liquid chromatography-mass spectrometry, 13C- and 1H-nuclear magnetic resonance analyses and high-performance liquid chromatography (as its 2,3,4,6-tetra-O-acetyl-beta-D-glucopyranosyl isothiocyanate derivative).     

Histological and electrophysiological analysis of the peripheral nerve allografts using an immunosuppressive agent

In peripheral nerve allografts, use of an immunosuppressive agent is one of the ways of reducing nerve rejection. FK506 is a newly discovered substance, extracted from Streptomyces tsukubaensis, and has strong immunosuppressive effects. In the present study, immunosuppressive effects of FK 506 were examined using allografts of rat sciatic nerves. Good nerve regeneration was demonstrated through 12 weeks in this model. The immunosuppressed group gained weight over the course of the experiment. Another study was performed to observe the histological changes caused by ceasing the administration of FK506. Administration of FK506 was terminated 12 weeks after grafting. At 8 weeks after cessation, cellular infiltration and large unmyelinated axons were observed in the extended subperineurial space of grafts. At 12 weeks, histological characteristics of rejection were not observed. In the electrophysiological study, the temporal dispersions were recorded at 4 and 8 weeks. However, the normal electrophysiological waves were recorded at 12 weeks after cessation. It was concluded that FK506 is effective for preventing rejection of nerve allografts without any serious side effects on rats, and findings of total rejection of grafts were not recognized after ceasing the administration of FK 506. In peripheral nerve allografts, short-term administration of an immunosuppressive agent is sufficient to lead to good nerve regeneration.     

Energy-optimal gait analysis of quadruped robots

It is important for walking robots such as quadruped robots to have an efficient gait. Since animals and insects are the basic models for most walking robots, their walking patterns are good examples. In this study, the walking energy consumption of a quadruped robot is analyzed and compared with natural animal gaits. Genetic algorithms have been applied to obtain the energy-optimal gait when the quadruped robot is walking with a set velocity. In this method, an individual in a population represents the walking pattern of the quadruped robot. The gait (individual) which consumes the least energy is considered to be the best gait (individual) in this study. The energy-optimal gait is analyzed at several walking velocities, since the amount of walking energy consumption changes if the walking velocity of the robot is changed. The results of this study can be used to decide what type of gait should be generated for a quadruped robot as its walking velocity changes. This work was presented, in part, at the Sixth International Symposium on Artificial Life and Robotics, Tokyo, Japan, January 15–17, 2001.