著者

吉村 寿人 飯田 敏行

出版者

THE PHYSIOLOGICAL SOCIETY OF JAPAN

雑誌

The Japanese Journal of Physiology (ISSN:0021521X)

巻号頁・発行日

vol.2, pp.177-185, 1951 (Released:2011-06-07)

参考文献数

10

被引用文献数

24 32

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Factors governing individual differences of temperature reaction to cold found by Lewis were studied by estimating reaction index devised in the first part of this study. Main results obtained are as follows:1. The reaction was found even a few days after birth and developed rapidly with lapse of days. The high reactivity in childhood was lessened in puberty and again it rose in young adult, after which it decreased gradually with the progress of age.2. A female adult seemed to show a little lower reactivity than a male.3. Native countries and racial specificity were proved to have an intimate relation with the reactivity, and a main factor of the influences was deduced to be the effect of training to cold.4. The Orochons were found to have the highest reactivity among all nations in Manchuria, and thus protecting themselves from frost-bite, adapted to their nomadic life in a cold country. The reactivity of Japanese adults recently came to Manchuria was the lowest of all the natives, while that of Japanese children was about the same with those of the native (the Mongols and the Chinese) children.5. A validity of training effect reported by Takahashi was ascertained, and it was proved that the effect was more remarkable on the youth than on the adult.6. Subjects of low reactivity were proved to show frequently high sympathetic tonus. Thus the tonus of autonomic nervous system had an intimate bearing with the reactivity.7. Main internal factors causing individual differences of the reaction were presumed to be differences of the following three: the morphological constitution, especially of blood vessels, the nervous control (activities) and other physiological properties of the skin. The experimental results mentioned above were explained from this point of view.

著者

吉村 寿人 飯田 敏行

出版者

THE PHYSIOLOGICAL SOCIETY OF JAPAN

雑誌

The Japanese Journal of Physiology (ISSN:0021521X)

巻号頁・発行日

vol.1, pp.147-159, 1950 (Released:2011-06-07)

参考文献数

7

被引用文献数

29 29

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1. There were found marked individual differences in the vascular reaction to cold reported by Lewis which protects the temperature fall of fingers or toes in severe cold. The difference should be an essential factor in constitutional difference of resistance against frost damage.2. A method was devised to determine the temperature reaction to cold by dipping the middle finger of the subject in ice water for 30 minutes, and measuring its skin temperature, and to compare the reactivity of the subject with one another by evaluating the so-called. “resistance index of frost bite” from the temperature curve thus determined. The method was called “a point test of the resistance against frost bite”.3. The resistance index estimated by the method was fairly reproducible, as far as the experimental conditions were constant. When measuring repeated attempts should, however, be avoided unless after several hours, and to have such living conditions before and during the measurement that do not cause changes in the thermoregulatory function.4. A marked seasonal change was found in the temperature reaction of one and the same subject, which increased in summer, and decreased in winter. The change was found to be mainly due to the change of room temperature. Even at the same room temperature, however, the reaction differed a little in summer and winter, i. e. is accelerated in the former when compared with the latter. The difference is probably due to an acclimatization of the vasomotor centre, in which the tonus changes to dilation of the skin vessels of extremities in summer, and constriction in winter.5. Influences of environmental temperature were examined in detail and it was found that the reactivity was accelerated by rise in room temperature in proportion with the magnitude of the reactivity itself. This fact can be explained by the fact that the reactivity of vessels is controlled by the tonus of the vasomotor, especially of the vasodilator, which changes with the environmental temperature.6. Effects of humidity on the temperature reaction was proved to exist, but not so marked as those of room temperature.7. Making use of the above experimental results, a method was devised to eliminate the errors in the temperature reaction due to the change of room temperature, and to evaluate the resistance index at the standard temperature of 20°C. from measurements at other temperatures. It was found that 81%-94% of values thus corrected coincided with those actually measured at 20°C. withinthe scope of experimental error, when the room temperature was between 15C°C. to 25°C.

著者

飯田 敏行

出版者

大阪大学

雑誌

基盤研究(C)

巻号頁・発行日

2000

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高純度サファイアの電気的特性を放射線照射下で調べた。その場測定の為の実験装置を製作し、中性子とγ線の照射実験を行った。一定のバイアス電圧下では、サファイア試料の放射線誘起電流はフラックスにほぼ比例し、単位呼吸線量率当りの電気伝導度増加係数は〜1.0×10^<-10>(S/m)(Gy/Sec)であった。また照射開始直後には大きな過渡電流が、そして、照射停止後には非常に遅い電流回復成分が観測された。さらに、外部バイアス電圧が無い状態でも放射線誘起電流が観測され、サファイア試料内部に電圧発生機構があることがわかる。これらの過渡電流やオフセット電圧の発生原因としては、試料の電荷蓄積や電荷キャリアの捕獲・再放出機構が考えられる。また、無機絶縁(MI)ケーブルについても同様の測定を行った。パルスX線照射実験では、ケーブル芯線に誘起される電荷量がパルス当りの吸収線量と芯線-シース間電圧にほぼ比例した。この事は、絶縁性低下の主要因が絶縁層内における電荷生成量とそのドリフトである事を示唆している。実験値を基にケーブル芯線に誘起されるパルス電荷量のシミュレーション計算を行った結果、絶縁材中の生成電子の平均ドリフト距離は、芯線-シース間電圧100Vに対して約15nmと推定された。この値の物理的妥当性については別方法によるクロスチェックが必要である。