著者

中村 康雄 齊藤 稔 林 豊彦 江原 義弘

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.20, pp.53-64, 2010 (Released:2017-02-15)

参考文献数

12

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サッカーは, キック動作を基本とした主に足でボールをコントロールするスポーツである. ボールを自在に操る蹴り脚は, 熟練者であるほど巧みな動きをする. そのため, 多くの先行研究では, 足のみを対象としてキック動作の定量的な測定・解析が行われてきた. しかし, キック動作は全身運動である. キック動作をさらに理解するためには, 足だけでなく, 蹴り脚の動作の要となる腰部の運動についても同時に測定し, 定量的に評価する必要がある. 本研究は, インステップキック動作を対象とし運動学・動力学解析することと, 熟練者と未熟練者の腰部の運動の違いを定量的に評価することを目的とした. キック動作はモーションキャプチャ・システムを用いて測定した. 熟練者と未熟練者の運動を評価した結果から, 腰部は, 上体の急激な屈曲運動の補助, 下肢へのエネルギー伝達, 姿勢の安定の3つの役割があると考えられた.

著者

梅谷 陽二 伊能 教夫

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.5, pp.19-27, 1980-05-25 (Released:2016-12-05)

著者

秋田 浩

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.13, pp.205-215, 1996-07-25 (Released:2016-12-05)

参考文献数

9

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In human forearms, the radius and the ulna are geometrically regarded as a combination of two spirals arranged in parallel, which rotate in opposite directions. I assume that the optimal curves for these spirals are geodesic curves on a surface of a cone, expressed as a formula as follows: [numerical formula] [numerical formula] [numerical formula] γ: the shortest distance from the vertex of the cone to the geodesic curve. [numerical formula], where φ is the vertex angle in developed plane of the cone. When two geodesic curves exist on a corn, the curve which is obtained by proper prolongation or reduction of one curve proves to be homothetic to the other. And all geodesic curves on a corn are symmetrical when they are prolonged to the proper extent. It is interesting that this symmetric formula is a common characteristic of hard tissues of animals. Furthermore, it seems that these geodesic curves exist in several hard tissues of many animals, as well as in humans. When two geodesic curves rotate with rolling contact at one point and at a constant angle between tangent planes of two-geodesic curves, the distance between the vertexes of two cones is kept constant. Using this geometric concept of geodesic curves on the cone, I designed a model of forearm movement. In this model, the humeral capitulum and the mid-point of the axis of the humeral trochlea are regarded as the vertexes of two cones. The above-mentioned hypothesis proposed the novel concept that morphology and functions can be generalized under the identical geometric theory with the geodesic curves on the cone.

著者

加藤 雄一郎 遠藤 博史 木塚 朝博

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.19, pp.35-46, 2008 (Released:2017-02-15)

参考文献数

46

被引用文献数

2

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刺激─反応 (S-R) 整合性とは, 選択反応課題において刺激と反応の空間的な位置関係が一致するときの方が, 一致しないときよりも反応時間が速くなる現象のことを言う. 本研究では, S-R整合性が情報処理過程における運動プログラムの構築にどのように関与しているのかを明らかにすることを目的に, 筋電図による反応時間分析, 脳磁図による大脳皮質活動の時系列分析を行った. 不整合反応は, 整合反応と比較してPremotor time, Motor timeが遅延し, 反応実行のための一次運動野の神経活動が弱いことが認められた. これらの結果は, S-R整合性が情報処理の時間的側面だけでなく運動プログラムの構築にも影響していることを示唆する. この脳内メカニズムについて, 二重ルート情報処理による自動的賦活と制御的賦活で説明する.

著者

八田 有洋 西平 賀昭 東浦 拓郎 金 勝烈

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.20, pp.43-52, 2010 (Released:2017-02-15)

参考文献数

44

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長期的な剣道鍛錬が脳─脊髄運動神経機能に及ぼす影響について, 末梢の脊髄運動神経機能については末梢運動神経伝導速度 (motor nerve conduction velocity : MCV) を用いて, 中枢の随意運動に伴う脳内処理過程については運動関連脳電位 (movement-related cortical potentials : MRCP) を用いて剣道鍛錬者と一般健康成人を対象に研究を行った. 1) 剣道鍛錬者は利き側だけでなく, 非利き側の尺骨神経伝導速度も一般健康成人より有意に速い値を示した. 2) 自発的な非利き側握力課題に先行して頭皮上より記録される運動準備電位 (Bereitschaftspotential : BP) の開始潜時は剣道鍛錬者が一般健康成人よりも有意に短い値を示した. 3) 一次運動野の皮質錐体路ニューロンの活動を反映するmotor potential (MP) 振幅は, 利き側と非利き側の握力課題において剣道鍛錬者が一般健康成人よりも有意に大きい値を示した. したがって, 脳─脊髄運動神経機能に長期的な運動トレーニングによる適応変化が生じる可能性が示唆された.

著者

平松 祐太 遠藤 雅也 林 豊彦 織田 孝 乾 浩明

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.23, pp.195-204, 2016 (Released:2017-08-01)

参考文献数

17

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筋委縮性側索硬化症や脳性まひをはじめとする重度肢体不自由者は, 個人に合った支援機器を利用すれば, 生活の質を著しく改善できる. その利用には操作スイッチが用いられているが, 現在の技術レベルでは, 身体の痙攣や振戦などの不随意運動がスイッチを入れてしまうと, 機器への誤入力が起こってしまう. そこでわれわれは, 不随意運動がある重度肢体不自者でも使用できるように, 3軸地磁気センサを用いた操作スイッチGSN/1を開発した. 不随意運動による誤入力を最小にするために, 統計的パターン認識法のひとつであるフィッシャーの線形判別法を応用した. さらに, 健常者を用いた2種類の不随意運動 (痙攣, 振戦) のモデルを開発し, 不随意運動も起きる条件下におけるGSN/1の操作性能の定量評価に用いた. 実験結果より, 正しい入力を許容レベルに維持するために必要とされる 「痙攣および振戦の条件」 について明らにした.

著者

岡田 徳次

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.3, pp.133-144, 1975-11-15 (Released:2016-12-05)

被引用文献数

2 4

著者

田中 英一郎 瀬戸口 隼 森 崇 三枝 省三 弓削 類

出版者

バイオメカニズム学会

雑誌

バイオメカニズム

巻号頁・発行日

vol.21, pp.145-156, 2012

被引用文献数

1

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<p>全身動作である歩行を補助するモビルスーツ型全身動作補助機を開発した. 本装置は, 上肢補助部と下肢補助部をモジュール化しているため分離ができ上下肢単体でも使用可能である. 同時に, 装着者および装置の両方を個別に免荷可能な走行リフターを開発し, これらを併用することにより転倒防止を図り, 移動しながら歩行障害患者の上下肢を使った歩行動作のリハビリテーションを可能とした. 本論文では, ニューロリハビリテーションでの使用を想定し, 歩行動作を上肢・下肢共に補助する全身動作補助機を製作し, 本装置を使用して歩行したときの脳活動の変化を把握し, 運動学習に対する有用性を検討したので報告する.</p>

著者

田中 英一郎 瀬戸口 隼 森 崇 三枝 省三 弓削 類

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.21, pp.145-156, 2012 (Released:2017-02-15)

参考文献数

24

被引用文献数

1 1

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全身動作である歩行を補助するモビルスーツ型全身動作補助機を開発した. 本装置は, 上肢補助部と下肢補助部をモジュール化しているため分離ができ上下肢単体でも使用可能である. 同時に, 装着者および装置の両方を個別に免荷可能な走行リフターを開発し, これらを併用することにより転倒防止を図り, 移動しながら歩行障害患者の上下肢を使った歩行動作のリハビリテーションを可能とした. 本論文では, ニューロリハビリテーションでの使用を想定し, 歩行動作を上肢・下肢共に補助する全身動作補助機を製作し, 本装置を使用して歩行したときの脳活動の変化を把握し, 運動学習に対する有用性を検討したので報告する.

著者

秋田 浩

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.14, pp.161-171, 1998-11-25 (Released:2016-12-05)

参考文献数

8

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I regarded an oval as a cross section of a torus (defined as closed curve E) cut by a plane II, parallel to the axis of rotation. Closed curve E is expressed as follows: [numerical formula] where a is the distance from the axis of rotation to plane II, and r is the distance from the axis of rotation to the center of the generating circle. I showed four shapes for closed curve E, which are similar to those of "real" eggs, by varying a values under constant r values. Then I demonstrated that shapes constructed by a computer are fairly similar to the "real" egg's shapes. I assumed that the most important function performed by the oval shapes of eggs is that eggs can stay near the original place when they are forced to roll. I showed that the greater the a value is, the shorter the radius of rotation of rolling eggs is.

著者

香原 志勢

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.11, pp.1-10, 1992-05-20 (Released:2016-12-05)

著者

平山 大作 藤井 範久 阿江 通良 小池 関也

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.19, pp.91-102, 2008

被引用文献数

4

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<p>本研究は, 大学野球投手を対象とし, 投球数の増加にともなうキネティクスの変化について検討することを目的とした. 実験試技は, 2台のフォースプラットフォームを埋設した簡易マウンドからストレートを投球するものであった. 被験者には, 10秒間隔で15球投げることを1イニングとし, イニング間に6分の休息をはさみながら9イニング, 計135球の投球を行わせた. 投球数とそれぞれのパラメータから単回帰分析を行い, 回帰係数の有意性について検定を行った (p<0.05). その結果, 投球数の増加にともない, ①踏込脚の股関節伸展の正仕事, 負仕事, 絶対仕事が減少する傾向がみられた. ②投球腕の肩関節内旋の正仕事が減少する傾向がみられた. ③投球腕への関節力による力学的エネルギーの流れの減少がみられた. ④投球腕の肩関節水平内転の正仕事および絶対仕事が増加する傾向がみられた. 以上のことから, 踏込脚の股関節伸展の仕事の減少は, 下肢のトレーニングの重要性を示唆するものであり, 投球腕の肩関節水平内転の仕事の増加は, "上肢動作に頼った投球動作" を示すものであると考えられる.</p>

著者

内山 孝憲 西川 龍朗 大西 祥平

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.17, pp.57-68, 2004 (Released:2005-04-15)

参考文献数

12

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The purpose of this study was to investigate muscle damage and reinforcement by electrical muscle stimulation (EMS).The first experiment involved two groups of athletes (Group 1 and Group 2) and one group of healthy volunteers who did not engage in daily exercises (Group 3 served as the control). The subjects’ triceps brachii muscles were stimulated electrically (EMS, subject&RSQUO;s variable tolerance: Group 1) and mechanically (concentric- and eccentric-resistance training of 60% MVC, RT: Group 2). For one of the subjects with EMS, the serum CPK levels of 3 and 4 days after the stimulation were approximately six times as high as that before the stimulation. The serum CPK levels of other subjects with EMS increased to twice or less of those before the stimulation. The serum CPK levels of subjects with RT did not change. The levels showed significant difference between subjects with EMS and RT, 2 and 5 days after the stimulation (Mann-Whitney test, p&LT;0.05).In the second experiment, the quadriceps femoris muscles were stimulated. EMS generating a force of 60% MVC was applied to each subject in Group 4 for 30 minutes every other day for a week. RT of 60% MVC was applied to each subject in Group 5. The subject did 30 trials, with 60 s resting time between every 10 trials, every other day for a week. The serum CPK levels of the subjects with EMS increased, but the increase rate varied with subjects. One of the subjects had more than six times as high serum CPK levels as that before the stimulation. Another subject had only one and half times as high serum CPK levels as that before the stimulation. There were significant changes with time after the stimulation (Friedman test, p<0.05). However, there were no significant differences between subjects with EMS and the control. For subjects with RT, the serum CPK levels increased slightly but there were no significant changes with time after the stimulation (p>0.05).In the third experiment, EMS was applied to the triceps brachii muscles of Group 1 and Group 3 for eight weeks. The non-athletes with EMS showed 30% increase of the maximum voluntary contractile force and they showed 38-54% improvement of endurance. The maximum voluntary contractile force of athletes with EMS did not change but the endurance showed 59% improvement. However the maximum voluntary contractile force of athletes without EMS decreased and the endurance did not change.In conclusion, we suggest that EMS could cause more severe muscle damage than concentric-, eccentric-resistance training. EMS reinforced the muscles of both athletes and non-athletes. Moreover, EMS showed stronger effects on non-athletes compared with the athletes.

著者

速水 則行 田中 英一 山本 創太 武内 浩樹

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.18, pp.23-34, 2006 (Released:2017-02-15)

参考文献数

20

被引用文献数

1 1

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動作解析において, これまであまり考慮されてこなかった筋疲労の影響を検討するため, 従来の力学的な筋モデルと組み合わせて使用する筋疲労モデルを開発した. そのため, 運動単位に着目し, それらを活性状態, 疲労状態により四つの状態に分割し, その状態変化を微分方程式により表現した. さらに, 代謝特性や疲労耐性の違いから三つの運動単位タイプに分割し, 運動単位の動員様式にはサイズ原理を取り入れてモデル化した. モデルの妥当性を検討するため, 先行研究や動的条件の疲労実験結果との比較を行ったところ, 筋疲労の特徴が再現できることを確認した. また, 各運動単位タイプの動員タイミング, 疲労の進行など, タイプ毎の特性の違いを再現できることが分かった.

著者

八田 有洋 西平 賀昭 東浦 拓郎 金 勝烈

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.20, pp.43-52, 2010

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<p>長期的な剣道鍛錬が脳─脊髄運動神経機能に及ぼす影響について, 末梢の脊髄運動神経機能については末梢運動神経伝導速度 (motor nerve conduction velocity : MCV) を用いて, 中枢の随意運動に伴う脳内処理過程については運動関連脳電位 (movement-related cortical potentials : MRCP) を用いて剣道鍛錬者と一般健康成人を対象に研究を行った. 1) 剣道鍛錬者は利き側だけでなく, 非利き側の尺骨神経伝導速度も一般健康成人より有意に速い値を示した. 2) 自発的な非利き側握力課題に先行して頭皮上より記録される運動準備電位 (Bereitschaftspotential : BP) の開始潜時は剣道鍛錬者が一般健康成人よりも有意に短い値を示した. 3) 一次運動野の皮質錐体路ニューロンの活動を反映するmotor potential (MP) 振幅は, 利き側と非利き側の握力課題において剣道鍛錬者が一般健康成人よりも有意に大きい値を示した. したがって, 脳─脊髄運動神経機能に長期的な運動トレーニングによる適応変化が生じる可能性が示唆された.</p>

著者

広川 俊二 松村 公志

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.11, pp.153-165, 1992-05-20 (Released:2016-12-05)

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The anterior-posterior displacement of the tibia elicited by the loading of the quadriceps and hamstring muscles was determined as a function of joint angle and muscle load using the data collected from five fresh cadaver knees with a highly accurate computerized radio-graphic technique. A two-dimensional mathematical model, taking into account movements and forces of the patellofemoral and tibiofemoral joints in the sagittal plane, was described and a computer simulation was performed to verify the experimental results. The simulated and experimental results closely coincided. Both the results demonstrated that quadriceps contraction can result in an anterior displacement of the tibia in the range of 0°to 40°of flexion, and in a posterior displacement in the range of 80°to 120°of flexion. However, hamstrings contraction always causes a posterior displacement of the tibia, irrespective of knee flexion angle. Thus it was concluded that quadriceps contraction has a direct impact on ACL stress, as hamstring contraction does on PCL stress. It was further concluded, however, that the absolute magnitudes of both the cruciate ligaments were not so much influenced by the thigh muscles' contraction as they were influenced by knee flexion angle, a conclusion that throws into question the assessment of cruciate ligament stresses by anterior-posterior displacement of the tibia. Some useful parameters that serve as a function of knee flexion angle were also introduced through the simulation: contact force and slipping ratio of the patellofemoral and tibiofemoral joints, variation of the patellar ligament force, and thigh muscle length. There is a linear relationship between quadriceps muscle force and patellofemoral contact force, whereas there is little relationship between quadriceps muscle force and tibiofemoral contact force. A semilinear relationship is observed between knee flexion angle and patello-femoral contact force. The tibiofemoral contact force shows a bell-shaped pattern against knee flexion angle. Variation of the patellofemoral slipping ratio shows a complex form in which the glide and roll of the patella on the femur take place in the opposite direction for 0°to 95°of knee flexion while glide and roll take place in the same direction for more than 95°of flexion. Variation of tibiofemoral slipping ratio shows that the femur mainly glides on the same position of the tibia between 30°and 90°of knee flexion. Linear relationships do exist between knee flexion angle and, respectively, quadriceps length and hamstrings length. Patellar ligament force varies from a similar value to about 60% of the quadriceps force as the knee flexes.

著者

藤田 欣也

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.13, pp.195-204, 1996-07-25 (Released:2016-12-05)

参考文献数

20

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The feasibility of a self-organized change of stretch reflex gain caused by the passive change of the ankle joint angle was discussed in the human soleus muscles. The amount of the maximal amplitude of Hoffman (H) reflex, normalized by the maximal direct motor (M) response, was used to evaluate the excitability of the soleus motoneuron. The H reflex amplitudes in 1) normal standing, 2) ten degree dorsiflexion, 3) ten degree plantarflexion, were measured in standing posture, and also in sitting posture with the same ankle joint angles, in ten neurologically intact subjects. The normalized H-reflex amplitude was decreased from 38 percent to 32 percent by dorsiflexion and increased to 44 percent in sitting posture. The amplitude in standing posture was also decreased 41 percent to 39 percent by dorsiflexion and increased 42 percent by plantarflexion. It was suggested that the motoneuron pool is inhibited by passive dorsiflexion and facilitated by passive plantarflexion. In 24 of the 30 inhibition by dorsiflexion was indicated in sitting posture; however, only 17 indicated the inhibition in standing posture. In 25 of the 30 facilitation by plantarflexion in sitting posture was indicated; however, only 16 indicated facilitation in standing posture. The tendency of the inhibition and facilitation was obvious in the sitting posture but not clear in the standing posture. Therefore, the change of the reflex loop gain appears to have no relation to the higher center control system such as that for postural control, and seems to be a local self-organized adaptation. Two hypotheses were proposed: 1) in feedback gain compensation, the change is for compensation of the muscle spindle sensitivity change, 2) in stiffness compensation, the change is for compensation of the nonlinearity of the joint stiffness. Measurement of the response to the mechanical perturbation is required to obtain answers for these hypotheses.

著者

加藤 一郎

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.1, pp.1-3, 1972-03-25 (Released:2016-12-05)

被引用文献数

2

著者

山口 仁一 玄 相昊 西野 大助 井上 貞敏 曽我 英司 高西 淳夫

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.14, pp.261-271, 1998-11-25 (Released:2016-12-05)

参考文献数

18

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Many groups are researching a biped walking robot, although they have different objectives in mind such as applications of modern control theory, the study of mechanisms, or practical use to medical fields. The authors and others are engaged in studies of biped walking robots, with "human form" as a key word, from two points of view: one is human engineering, and the other is toward the development of anthropomorphic robots. The authors and others have obtained the following results to date. In 1984, the authors and others succeeded in achieving a dynamic biped walking of 1.3 [s/step] by the use of a hydraulic biped walking robot, WL-10 RD (Waseda Leg-No.10 Refined Dynamic). From 1986 to 1994, the authors developed hydraulic biped walking robots of the WL-12 series that compensated for lower limbs moment using an upper body and realized not only fast dynamic biped walking (0.54 [s/step] with a step length 0.3 [m]) but also walking on an unknown surface. In 1995, the authors developed an electrical powered biped walking robot WL-13, in which each leg joint is driven antagonistically via a rotary-type, nonlinear spring mechanism, and realized quasi-dynamic walking (7.68 [s/step] with a 0.1 [m] step length). In the current research concerning a biped walking robot, however, there is no developed example of a life-size biped walking robot which can perform manipulation and locomotion by dynamically coordinating arms and legs. Therefore, the authors proposed the construction of a biped humanoid robot that has a hand-arm system, a head system with visual sensors, and antagonistic driven joints using a rotary-type non-linear spring mechanism, on the basis of WL-13. We designed and built it. In addition, as the first step to realize the dynamically coordinated motion of limbs and trunk, the authors developed a control algorithm and a simulation program that generates the trunk trajectory for a stable biped walking pattern even if the trajectories of upper and lower limbs are arbitrarily set for locomotion and manipulation respectively. Using this preset walking pattern with variable muscle tension references corresponding to swing phase and stance phase, the authors performed walking experiments of dynamic walking forward and backward, dynamic dance and carrying, on a flat level surface (1.28 [s/step] with a 0.15 [m] step length). As a result, the efficiency of our walking control algorithm and robot system was proven. In this paper, the mechanism of WABIAN and its control method are introduced.

著者

赤松 幹之

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.7, pp.59-68, 1984-04-25 (Released:2016-12-05)

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Pain sensations on the skin are generated by mechanical nociceptive stimuli. However, the question of what constitutes a mechanical nociceptive stimulus is still unclear. Therefore, in this study, mechanical factors which cause cutaneous mechanical nociception were investigated by computer simulation of an elastic model of the skin. In order to compare them with the results of the simulation, psycho-physical experiments on awake human subjects were performed. Indentation threshold which is indentation amplitude of the stimulus needle from the skin surface to the depth where the pin prick is first felt, were measured as a parameter of stimulus for various pins and cylindrical needles. The apparatus which measured indentation thresholds was composed of a touch sensor which detects the initial touch of the needle to the skin, a noncontacting type displacement measurement device which measures the amplitude of displacement of the needle, and the button by which the subject indicates the threshold of pain sensation. The results showed that sharp pins had shallower indentation thresholds and cylinders with small radii had shallower thresholds. The elastic model of the skin was based on the three-dimensional elastic theory that assumes that the skin is a homogeneous, isotropic, and semiinfinite elastic medium. The nociceptors, the receptors of pain sensation, were supposed to be distributed pseudo randomly at a certain depth in the skin. Each nociceptor was assumed to respond to a mechanical factor such as vertical strain, horizontal stress, and so on. The indentation threshold was defined as the smallest indentation amplitude of the needle on which the mechanical factor at one of nociceptors reached the predetermined threshold. The value of the threshold was determined to give a fit between the result of simulation and experimental observation for one of the needles. Setting the threshold at this value, indentation thresholds of other needles were examined by computer simulation, and a comparison with the experimental results was made. In all, twenty kinds of mechanical factors, stresses, strains, principal stresses and strains, and differentials of strains were included in the hypothesis for adequate stimulus to the nociceptor. Computer simulation showed that the vertical differential of vertical compressive strain and the vertical differential of averaged horizontal tensile strain explained the experiment most effectively. From this result these two differentials of strain are considered to be the candidates for the mechanical factor of nociception.