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Recently, we have succeeded in identifying the structure of the adsorption layer of ethanol on a silica surface in cyclohexane to be a hydrogen-bonded linear aggregate (polymer), which we call a surface molecular macrocluster. In this work, we studied the effect of the miscibility of liquids on the formation of the surface molecular macroclusters for confirming that this is a surface induced phenomenon. We investigated the interaction and the structure of methanol adsorbed on a silica surface in methanol−cyclohexane binary liquids by a combination of colloidal probe atomic force microscopy, adsorption excess isotherm measurement, and FTIR spectroscopy using the attenuated total reflection (ATR) mode, and compared the results with those of the ethanol−cyclohexane and 1-propanol−cyclohexane binary liquids. The former system is immiscible at methanol concentrations of ca. 8−90 mol %, and the latter two are miscible at any composition. At 0.03 mol % methanol, which is far from the critical concentration for the phase separation, the contact of the methanol macrocluster layers formed on the silica surface brought about the attraction from a distance of 42 ± 5 nm which was similar to that observed in ethanol−cyclohexane. At a methanol concentration of 9.0 mol %, above bulk phase separation, completely different force profiles were observed. These results demonstrated that the molecular macrocluster formation was different from the wetting induced by the bulk.

Endothelin-1 (ET-1) induces cardiac hypertrophy. Because Ca(2+) is a major second messenger of ET-1, the role of Ca(2+) in ET-1-induced hypertrophic responses in cultured cardiac myocytes of neonatal rats was examined. ET-1 activated the promoter of the beta-type myosin heavy chain gene (beta-MHC) (-354 to +34 base pairs) by about 4-fold. This activation was inhibited by chelation of Ca(2+) and the blocking of protein kinase C activity. Similarly, the beta-MHC promoter was activated by Ca(2+) ionophores and a protein kinase C activator. beta-MHC promoter activation induced by ET-1 was suppressed by pretreatment with the calmodulin inhibitor, W7, the Ca(2+)/calmodulin-dependent kinase II (CaMKII) inhibitor, KN62, and the calcineurin inhibitor, cyclosporin A. beta-MHC promoter activation by ET-1 was also attenuated by overexpression of dominant-negative mutants of CaMKII and calcineurin. ET-1 increased the activity of CaMKII and calcineurin in cardiac myocytes. Pretreatment with KN62 and cyclosporin A strongly suppressed ET-1-induced increases in [(3)H]phenylalanine uptake and in cell size. These results suggest that Ca(2+) plays a critical role in ET-1-induced cardiomyocyte hypertrophy by activating CaMKII- and calcineurin-dependent pathways.

Triphenyl phosphite was studied by powder X-ray diffractometry, adiabatic calorimetry, and dielectric relaxation measurements. The highly correlated liquid, denoted by LC, phase corresponding with the glacial phase by Cohen et al. was prepared by annealing the ordinary liquid, denoted by LN, at 210 K, and different states in the LC phase were formed by further annealing the prepared LC-phase sample at 215 and 220 K. After the temperature jump from 210 to 215 K, two different processes first of heat absorption and then heat evolution were found to exist in the LC phase. The first process showed reversible temperature dependence of the relaxation times near the temperature of LC-phase formation as far as the process bringing the latter heat evolution effect did not proceed any further. The glass transition temperatures were found to be 209.9, 212.6, and 214.0 K for the LC-phase samples formed at 210, 215, and 220 K, respectively. The fragility parameters of the respective samples were 104, 99, and 94, comparable with 104 in the LN phase. The second process changed the relaxation times of the first process irreversibly to increase as the temperature of LC-phase formation increases in the order of 210, 215, and 220 K. The temperature dependences of β-relaxation times were found to coincide completely with each other between the LN and LC phases. Those results were interpreted by the “intracluster rearrangement for α process” model combined with the “cluster structure for supercooled liquid and glass” model; the above second process corresponds to the increase/decrease in the size of the somehow “structurally ordered” region (named a cluster) and the first one to the order/disorder process of molecules within each cluster, namely the ordinary α process. The above second effect of heat evolution at 215 K is thus due to the development of ordering following the increase in the cluster size. The β relaxation would be attributed to the rearrangement of molecules between the clusters.

Dynamic analysis and control for accurate magnetic disk head positioning using a compact double-carriage rotary actuator is presented. Rolling mode vibration, due to a small dynamic imbalance in the head arm carriage, is one of the major factors in positioning servo instability. To avoid such vibration, structural symmetry should be maintained along the actuator pivot axis. Vibration interaction in the double-carriage rotary actuator is also clarified by mathematical modeling of a disk drive. The positioning error due to the interaction is reduced by one-third to the submicron order, even during very high-speed accessing, by a cross-feedforward decoupling control using a precompensator based on the model.

The aim of the present study was to set targets for each spinal lesion level after determining the relationship between the spinal lesion level and movement abilities in patients with tetraplegia following injury to the cervical cord. A total of 109 patients, 96 men and 13 women were included in the study. We mainly examined locomotion and transfer capabilities according to Zancolli's classification. The results of this study showed that 50% of the patients classified as C6A, 75% of C6B1and 96% of the patients classified C6B2accomplished bed transfer. The number of patients who could manage toilet transfer was 53% in the group classified as C6B1and 85% in group C6B2. These results suggest that achievement of those classified as C6B2is a clue to the assumption that the patient will achieve toilet transfer capability and can perform ADL independently.

Summary Systematic morphological study of the cerebral arteries was made in six autopsy cases of ruptured aneurysms. The time course of the arterial luminal narrowing was observed by repeated angiograms, and segments of the narrowed arteries were studied histologically.

Summary Antimicrotubule agents, colchicine, vinblastine, and griseofulvin, induced conspicuous morphological anomalies inBryopsis plumosa. First, following cessation of protoplasmic streaming within 15 minutes, elongation stopped in a few hours. Second, innumerable protrusions or new growth points generated over the cell flank in a few days. Similar phenomena were observed in the cells which were subjected to high pressure or low temperature both of which are known to disrupt microtubule.

Summary For the experimental studies on chronic coronary stenosis, an ameroid constrictor was modified to facilitate serial cineangiographic evaluation of the degree of arterial narrowing. A radiolucent plastic ring instead of a stainless frame was used to prevent outward swelling of the ameroid material.

Dynamic analysis and control for accurate magnetic disk head positioning using a compact double-carriage rotary actuator is presented. Rolling mode vibration, due to a small dynamic imbalance in the head arm carriage, is one of the major factors in positioning servo instability. To avoid such vibration, structural symmetry should be maintained along the actuator pivot axis. Vibration interaction in the double-carriage rotary actuator is also clarified by mathematical modeling of a disk drive. The positioning error due to the interaction is reduced by one-third to the submicron order, even during very high-speed accessing, by a cross-feedforward decoupling control using a precompensator based on the model.