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T Togawa

Publications and source records attributed to T Togawa.

At least 145 records · Page 8Linked to original sources
PubMed1983

[Portable multi-purpose device for monitoring of physiological informations].

Unconstrained system that measures physiological information as skin temperatures and heart rate per unit time of a human subject was developed. The system contained portable device included memory control unit, instrumentation unit, timer and batteries, read-out unit, test unit and verify unit. Total number of data and channels, and interval were selected by switches in the memory control unit. The data from the instrumentation unit were transferred to memory control unit and stored in the Erasable Programmable ROM (EPROM). After measurement, EPROM chip was taken off the memory control unit and put on the read-out unit which transferred the data to the microcomputer. The data were directly calculated and analyzed by microcomputer. In application of the instrumentation unit, 8-channel skin thermometer was developed and tested. After amplification, 8 analog signals were multiplexed and converted into the binary codes. The digital signals were sequentially transferred to memory control unit and stored in the EPROM under controlled signal. The accuracy of the system is determined primarily by the accuracy of the sensor of instrumentation unit. The overall accuracy of 8-channel skin thermometer is conservatively stated within 0.1 degree C. This may prove to be useful in providing an objective measurement of human subjects, and can be used in studying environmental effect for human body and sport activities in a large population setting.

Adult↗
PubMed1983

[Body acceleration measurement and oxygen uptake during jumping].

The integral of the positive acceleration per unit time was defined as physical activity. The device that measured physical activity during jumping was developed and the relationship between physical activity by acceleration measurement and energy expenditure was evaluated. Acceleration wave forms of back were measured with strain gauge type accelerometer. After amplification and rectification, the positive acceleration wave forms integrated. When the output of the integrator reached the threshold of comparator, the output of the comparator contained trigger signal. The physical activity was determined by the total counts of the trigger signal. 10 males jumped at four jumping cycles (20, 40, 60 min-1 and random) and 24 children jumped at random jumping. Oxygen uptake, physical activity and heart rate were simultaneously measured. The results showed the oxygen uptake, physical activity and heart rate of males were linearly related to jumping cycle. However, oxygen uptake of random jumping was less than one of 60 min-1 jumping in spite of the greater physical activity. This result indicated that the random jumping was operated efficiency due to the effect of elastic bounce. The oxygen uptake/body weight of males had good correlation to physical activity (r = 0.922), and heart rate (r = 0.902). Also the oxygen uptake/body weight of males and children had good correlation to physical activity (r = 0.953). The difference of ages and weights was not significant during jumping. These results mentioned to be useful in providing an objective evaluation of the physical activity of human subjects during jumping.

Acceleration↗
PubMed1982

[Calf blood flow at rest evaluated by thermal measurement with tissue temperature and heat flow and 133Xe clearance (author's transl)].

The regional blood flow in the calf was determined simultaneously by thermal measurement and by 133Xe clearance technique. Calf blood flow (Ft) by thermal measurement was accounted for by the equation of the form Ft = (CdTd + Ho - Mb)/rho bCD (Ta--Td), where Cd is thermal capacitance of the calf compartment, Td is the change of calf tissue temperature, Ta is arterial blood temperature, Td is calf tissue temperature, Ho is the heat dissipation from the compartment to the environment, Mb is estimated metabolism of the calf tissue and rho bCb is the product of density and specific heat of blood. The healthy men were chosen for the experiments. Total calf blood flow was 2.53 +/- 1.31 ml/(min-100 ml calf), and muscle blood flow was 2.63 +/- 1.69 ml/(min-100 ml muscle) and skin blood flow 7.19 +/- 3.83 ml/(min-100 ml skin) measured by 133Xe clearance. On the basis of the results, an estimate has been made of the proportions of the calf volume which can be ascribed to skin and muscle respectively. Estimated muscle and skin blood flow were correlated with total calf blood flow (r = 0.98).

Adult↗
PubMed1982

Ultrastructural changes in the endothelial surface of the canine carotid artery induced by wall shear stress load.

To study the morphological changes in the endothelial surface of the artery induced by wall shear stress load, an arterio-venous shunt was constructed between the common carotid artery and the external jugular vein in 21 dogs. The ultrastructural changes in the endothelial surface were observed by scanning electron microscopy after the measurement of the hemodynamic parameters. In acute experiments (3 days or 1 week postoperative), the clear ultrastructural changes, such as the disturbance of the smooth folds, the find transverse wrinkles, the small spindle swellings, the splitting of the intercellular junction of the endothelial cells and occasionally the desquamation of the endothelial cells, were significantly observed as proportional to the elevated flow rate ratio (fs/fc, fs: flow rate of the shunted artery, fc: flow rate of the control artery). In subacute experiments (2 or 4 weeks postoperative), the small spindle swellings were observed in the shunted artery with high flow rate ratio. In chronic experiments (5 or 6 months postoperative), these changes were less proportional to the flow rate ratio. These morphological changes were significant in the disturbance of the endothelial barrier in acute experiments and they were significant in adaptive regulatory change in the chronic experiments. These support our previous observation (Am. J. Physiol. 239, H14-21, 1980). The possibility of the wall shear stress for atherogenesis was discussed.

Animals↗
PubMed1982

[Transducers].

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Blood Flow Velocity↗