• Title/Summary/Keyword: Body segments

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Resource conservation using whole body autophagy: Self-digestion of shedded gut lining cells in the small intestine

  • Lee, Phil Jun;Cho, Namki;Yoo, Hee Min;Chang, Sun-Young;Ko, Hyun-Jeong;Kim, Hong Pyo
    • Korean Journal of Food Science and Technology
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    • v.52 no.3
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    • pp.244-248
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    • 2020
  • To retain valuable resources, organisms adopt several strategies including coprophagy. Cells covering the outer skin and internal digestive lumen are actively recycled to maintain their integrity. In present study, we suggested that the small intestine can consume dead cells in a manner similar to how it consumes protein from the diet. We examined the eluates from five segments of the mouse small intestine and cecum and 2 segments of the large intestine and small intestine tissue, and detected immunoreactivity with eukaryotic caveolin-1 and β-actin antibodies only in the cecum and 2 segments from the large intestine. Bacterial agitation of the mouse intestine with Shigella disrupted the architecture and absorptive function of the small intestine. Small intestine eluates were immunoreactive with murine caveolin-1 and contained heme as determined by dot blot analysis. We concluded that the body conserves resources in the small intestine by disposing of and recycling shedded cells.

A Study of the Effects of the Trunk Angles and the Upper Ann Angles on Workloads in the Lifting Work (들기작업 시 몸통각도와 상완각도가 작업부담에 미치는 영향에 관한 연구)

  • Chang, Seong-Rok;Park, Hyung-Gu
    • Journal of the Korean Society of Safety
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    • v.24 no.2
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    • pp.69-75
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    • 2009
  • It is well-known that lifting capacity of a worker is influenced by body posture during the task. When a task analyst make use of RULA and REBA Trunk and upper arm angles are recorded in a separate item. It means that the interaction between the angles of two body segments may be ignored in a final score. The NLE(NIOSH Lifting Equation) has been used to supplement this problem. However, there is no study to validate the result of RWL (Recommended Workload Limit) under the existence of interactions between trunk and upper arm angles. The goal of this study was to assess the effect of the interaction between trunk and upper arm angles. Three responses, including NMVC(normalized maximum voluntary contraction), RWL(Recommended Weight Limit) and subjective judgment in psychophysical method (Borg's scale), were recorded according to the combinations of three trunk angles and nine upper arm angles. The results showed that lifting capacity is highly influenced by interaction of two body segments(trunk and upper arm). It means that the task workload has to be analyzed along with the interaction of trunk angles and upper arm angles when the task analyst assesses potential risk factors on the postures. This study may be able to be a fundamental study to develop an assessment method for lifting task analyses according to body postures.

Kinetic Analysis of the Lower Body Joints on Golf Swing (골프 스윙시 하지의 운동역학적 분석)

  • Chang, Jae-Kwan;Ryu, Jae-Kyun
    • Korean Journal of Applied Biomechanics
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    • v.24 no.4
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    • pp.339-347
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    • 2014
  • The purpose of this study was to investigate joint torques of lower body segments on professional golfers. Three dimensional swing analysis was conducted on the seven subjects. Each subject was asked to swing with 45 inches of Callaway driver, where two force plates (9286AA, Kistler, Switzerland) were built, with his normal speed and tempo. The resultant joint moments of the lower extremities were computed using the kinematic variables of the segments, anthropometric measures and the ground reaction force data by inverse dynamics method. Based on the results of this study, the following conclusions were drawn; It was found that the left ankle joint torque at 3rd phase was increased toward extension on the X-axis and abduction on the Y-axis. The left knee joint torque was alternated from flexion to extension direction in order to lower down the body weight at the beginning of the downswing. The lumbar joint torque was alternated from flexion to extension in order to speed up the upper body rotation which could increase the club head speed ultimately.

A Review on the Mechanism of Human Postural Control (인간의 자세조절 메커니즘에 대한 연구)

  • Lee, Dong-Woo
    • Korean Journal of Applied Biomechanics
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    • v.15 no.1
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    • pp.45-61
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    • 2005
  • Stance is defined as any state in which the total mass of the body is supported by the feet. In order to maintain stance, the sum of gravito-inertial forces acting on the body must be registered by equal and opposite forces at the region of contact between the organism and the support surface. Balance is controlled by applying forces to the surface of support so as to maintain the body's center of mass vertically above the feet. for a muIti-segment organism, there can be a variety of ways in which balance can be controlled, since movements of different body segments can have similar effects on the control of balance. In general, the organism tends to have a body configuration that is aligned with gravito-inertial force when there are no external forces acting on it. If any segments of the body are not aligned with gravito-inertial force vector, a torque on that segment would tend to move the body's center of mass. The maintenance of postural stability is accomplished in humans by a complex neural control system. This requires organizing integrating and acting upon visual, vestibular, and somatosensory input, providing orientation information to the postural control system. The information necessary to control and coordinate movement is provided by the visual sense of eye position with respect to the surrounding surface layout, the vestibular sense of head orientation in the gravito-inertial space, and the somatic sense of body segment position relative to one another and to the support surface. In this study, perception and action capability was examined from various points of view. The underlying assumption of the study was that the change of postural configuration could be effected by organism, environment and task goal.

Human Posture Dynamics in Response to the Horizontal Vibration

  • Shin, Young-Kyun;Fard, M.A.;Inooka, Hikaru
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.1504-1508
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    • 2003
  • The functional behavior of each body segments were investigated with respect to human standing posture when they were exposed to the horizontal vibration in the sagittal plane. This study is processed by experimental approach. The data is analyzed, both in the time domain and in the frequency domain. Random and multisinusoidal vibration was used as input. The ankle, hip, and head were employed as the significant body segments. High relative movements were present between hip and head, and there was no significant relationship between ankle and head. Variations of visual input produced a significant postural effect.

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A nonlinear optimization model of lower extremity movement in seated foot operation (비선형 최적화기법을 이용한 하지근력 예측 인체공학 모형)

  • 황규성;정의승;이동춘
    • Journal of the Ergonomics Society of Korea
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    • v.13 no.2
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    • pp.65-79
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    • 1994
  • A biomechanical model of lower extremity in seated postures was developed to assess muscular activities of lower extremity involved in a variety of foot pedal operations. The model incorporated four rigid body segments with the twenty-four muscles to represent lower extremity. This study deals with quasi-static movement to investigate dymanic movement effect in seated foot operation. It is found that optimization method which has been used for modeling the articulated body segments does not predict the forces generated from biarticular muscles and antagonistic muscles reasonably. So, the revised nonlinear optimization scheme was employed to consider the synergistic effects of biarticular muscles and the antagonistic muscle effects from the stabilization of the joint. For the model validation, three male subjects performen the experiments in which EMG activities of the nine lower extremity muscles were measured. Predicted muscle forces were compared with the corresponding EMG amplitudes and it showed no statistical difference. For the selection of optimal seated posture, a physiological meaningful criterion for muscular load sharing developed.

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비선형 최적화기법을 이용한 하지근력 예측 인체역학 모형

  • 황규성;정의승;이동춘
    • Proceedings of the ESK Conference
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    • 1994.04a
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    • pp.124-135
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    • 1994
  • A biomechanical model of lower extremity in seated postures was developed to assess muscular activities of lower extremity involved in a variety of foot pedal operations. It is found that nonlinear optimization method which has been used for modeling the articulated body segments does not predict the forces generated from biarticular muscles reasonably, so the revised nonlinear optimization scheme was employed to consider the synergistic effects of biarticular muscles in the model, assuming that the muscle forces are distributed proportionally based on their physiological cross sectional area and moment arm. The model incorporated four rigid body segments with the nine muscles to represent lower extreimity. For the model valida- tion, three male subjects performed the experiments in which EMG activities of the nine lower extremity muscles were measured. Predicted muscle forces were compared with the corresponding EMG amplitudes and it showed no statistical difference. The developed model can be used to design and to assess the pedals and foot-related equipments design.

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Segmental Bioelectrical Impedance Analysis(SBIA) for Determining Body Composition (부위별 생체 전기 임피던스법을 이용한 체성분 분석에 관한 연구)

  • 차기철;손정민;김기진;최승훈
    • Korean Journal of Community Nutrition
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    • v.2 no.2
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    • pp.179-186
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    • 1997
  • A new bioelectrical impedance method has been developed and evaluated. The electrodes; were made of stainless steel and electrical interfaces were created by an upright subject gripping hand electrodes and stepping onto foot electrodes. Eight tactile electrodes were in contact with surfaces of both hands and feet; thumb, palm and fingers, front sole, and rear sole. Automatic on-off switches were used to change current pathways and to measure voltage differences for target segments. Segmental body resistances and whole body resistance(RWHOLE)were measured in 60 healthy subjects. Segmental resistances of right arm(RRA), left arm(RLA), trunk(RT), right leg(RRL) and left leg(RLL)were310.0$\pm$61.6$\Omega$, 316.9$\pm$64.6$\Omega$, 25.1$\pm$3.4$\Omega$, 236.8$\pm$31.2$\Omega$ and 237.6$\pm$30.4$\Omega$, respectively. Individual segmental impedance indexes(Ht2/RRA, Ht2/RT, and Ht2 /RLA) were closely related to lean body mass(LBM)as measured by densitometry ranged from r=0.925 to 0.960. Ht2/(RRA+RT+RLA) predicted LBM slightly better(r=0.969) than the traditional index, Ht2/RWHOLE(r=0.964), supporting the accuracy of the segmental measurement. A multiple regression equation utilizing Ht2/RRA, Ht2/RT and Ht2/RRL predicted LBM with r=0.971. Ht2/RRA term of the regression contributed to more than 40$\%$ of the LBM prediction, indicating that lean mass of arm represented whole body LBM more closely than other body segments. The new bioimpedance method was characterized by upright posture, eight tactile electrodes, segmental measurements and utilization of electronic switches in comparison with the traditional method. The measurement with this new method was extremely reproducible, quick and easy to use.

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esearch on Biomechanics of Korean Body Segments (한국인 인체분적의 동특성에 관한 연구)

  • 박수찬;박세진;황민철
    • Proceedings of the ESK Conference
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    • 1996.04a
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    • pp.291-300
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    • 1996
  • This study is to determine the biomechanical characteristics of Korean. Male 58 and Female 54 were participated for the measurement which was performed by immersion method and reaction board method. Body parts were head with neck, trunk, upper arm, forearm, hand, thigh, leg, and foot. Their volumes were measures by immersion method. Their weight were determined by using Dempster(1995), Drills and Contini(1969) density data. Each center of body part weight were determined by specific posture on the reaction board. The postures were asked to the subject forearm- lifted posture, total let- lifted posture, foot-lifted posture. According to each posture, the center of each part were calculated.

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The relationships between body-cathexis and clothing image preferences in male college students (남자대학생의 신체만족도와 의복이미지 선호의 관계연구)

  • 나영주
    • Journal of the Korean Society of Costume
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    • v.49
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    • pp.65-72
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    • 1999
  • The purpose of this study was to investigate the relationships between body-calthexis and clothing image preferences in male college students. The sample included 28 male college students and an instrument was developed based on the previous studies. The statistical analyses used for this study were factor analysis cluster analysis and t-test. The result of factor analysis showed that body-cathexis consisted of four areas of body parts: face/head upper body middle body and lower/total body. Clothing image preferences consisted of 'strong vs weak' 'soft vs hard' 'young vs mature' 'mannis vs feminine' and 'distinguished vs undistinguished' images. Cluster analysis revealed that male college students are segmented into two groups. and the two groups differed in regard to clothing image preferences such as 'strong vs weak' 'young vs mature' and 'mannish vs feminine' images. In addition the two consumer segments were different concerning body-cathexis for middle body and all body areas combined. The consumers who preferred feminine weak and mature clothing images were more satisfied with their middle area of the bodies and all body areas combined.

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