• 제목/요약/키워드: G-Force

검색결과 1,515건 처리시간 0.03초

교원섬유 기질을 이용한 3차원 세포 배양 모델에 기계적인 힘을 가하는 경우 기질을 통하여 세포에 가해지는 힘의 특성에 대한 비교 분석 연구 (THE FINITE ELEMENTS ANALYSIS IN THE THREE DIMENSIONAL CELL CULTURE MODEL OF THE COLLAGEN MATRIX ACCORDING TO THE APPLICATION FORCE)

  • 김현종;류인철;박준우;김성곤
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제34권2호
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    • pp.151-156
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    • 2008
  • Different kinds of forces can be applied to the biological tissue. The analysis of the applied force is highly important to explain the mechanism of cellular response. In this study, the applied force to the collagen gel was analyzed by the finite elements analysis. The model received two different kinds of static force (compression and tension). The force range was 50g to 400g. In results, von Mises stress was concentrated in the peripheral region in the compression model. It was concentrated in the central area in the tension model. However, the compressive force was high in the peripheral area of the compression model and the tensional force was also high in the same area of the tension model. In conclusion, the applied force could be different to the region and it should be considered in the experiment to analyze the effects of the mechanical force on the cells.

3차원 측정기를 위한 원자간력 프로브 성능 연구 (A Study on the Performance of Atomic Force Probe for Coordinate Measuring Machines)

  • 정판곤;배규현;홍성욱
    • 한국공작기계학회논문집
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    • 제17권4호
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    • pp.75-80
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    • 2008
  • This paper presents an atomic force probe for triggering coordinate measuring machines(CMMs). A rigorous comparison is made between touch trigger probe and atomic force probe for CMMs. Typical CMMs(touch trigger probe based CMMs) often lead to some errors associated with object curvature and difference in triggering sensitivity. Their applicability is limited only to hard objects. The aim of this work is to develop a trigger sensor for CMMs using atomic force. In order to show the applicability of atomic force as a trigger sensor, a cylindrical shape is measured with a CMM and an atomic force microscope. Three different touch probe heads with different ball sizes are tested. The experiments show that smaller ball provides better results for curved objects. The experimental results also show that the performance of atomic force as a trigger sensor is about that of the smallest ball probe. In addition, experiments are also performed to measure soft objects. Finally, this paper suggests and verifies a trigger sensor using atomic force for CMMs.

미세유체 칩 내에서 유전영동 집게(Dielectrophoretic Tweezers) 를 이용한 단백질A와 면역 글로불린 G의 결합에 관한 연구 (Investigation of the Binding Force between Protein A and Immunoglobulin G Using Dielectrophoretic(DEP) Tweezers Inside a Microfluidic Chip)

  • 곽태준;이재우;윤대성;이상우
    • 대한의용생체공학회:의공학회지
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    • 제34권3호
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    • pp.123-128
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    • 2013
  • The 'Dielectrophoretic Tweezers(DEP Tweezers)' can be used as a facile, economical toolkit for quantitative measurement of chemical and biological binding forces related to many biological interactions within a microfluidic device. Our experimental setup can probe the interaction between a single receptor molecule and its specific ligand. Immunoglobulin G(IgG) functionalized on polystyrene microspheres has been used to detect individual surface linked Staphylococcus protein A(SpA) molecules and to characterize the strength of the noncovalent IgG-SpA bond. It was measured and compared with the existing measurements. Measured single binding force of between Goat, Rabbit IgG and SpA were $17{\pm}7pN$, $74{\pm}16pN$. This work can be used to investigate several different ligand-receptor interactions and antigen-antibody interactions.

Correlations among Shearing Force, Morphological Characteristic, Chemical Composition, and In situ Digestibility of Alfalfa (Medicago sativa L) Stem

  • Liu, L.;Yang, Z.B.;Yang, W.R.;Jiang, S.Z.;Zhang, G.G.
    • Asian-Australasian Journal of Animal Sciences
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    • 제22권4호
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    • pp.520-527
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    • 2009
  • Alfalfa (Medicago sativa L) is a high-quality forage for ruminants and the main stem is the dominant morphological component contributing to the forage nutritive value in mature alfalfa forage. Shearing force, a fracturing property of plant stem, is an important indictor of forage value. The objectives of this study were to investigate the effects of morphological characteristic on shearing force, the relationship between shearing force and chemical composition, and the relationship between shearing force and in situ digestibility of alfalfa stem. The results showed that linear density (weight per unit length of stem) was more important than chemical composition in affecting shearing force. There was a positive relationship between lignin content and shearing force (r = 0.78). Correlations were not found between shearing force and other chemical components such as neutral detergent fiber (NDF), acid detergent fiber (ADF), cellulose and hemicelluloses. In situ digestibility (of dry matter and NDF) was related to shearing force. A negative correlation was found between shearing force and dry matter (DM) digestibility (r = -0.70), and there was also a negative correlation between shearing force and NDF digestibility (r = -0.87). When shearing force was standardized for stem diameter or stem linear density, the relationship between shearing force and digestibility was consistent regardless of stem diameter and stem linear density. Shearing force was significantly correlated with lignin content and in situ digestibility (of DM and NDF), and was a more direct indicator for estimating forage nutritive value related to animal performance, so it can be used to predict the forage value of alfalfa.

Adjuvant에 의해 유발된 관절염 백서모델에 있어서 대방풍탕의 진통효과 (Analgesic Effect of Daebangpung-tang on a Rat Model of Adjuvant-induced Arthritis)

  • 성병곤;박영일;김재주;김미선;김남권;임규상
    • 동의생리병리학회지
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    • 제16권1호
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    • pp.124-132
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    • 2002
  • Daebangpung-tang(DBPT) is one of the prescriptions used for the treatment of rheumatoid arthritis(RA) in oriental medicine. The present study aimed to examine the analgesic effect of DBPT on a rat model of CFA-induced arthritis, which is not identical to human auto-immune arthritis although it does have many features in common with RA, and the relation between DBPT-induced analgesia and steroid hormones. CFA-induced arthritis rat model used to test the effect of DBPT was chronic pain model. After the induction of arthritis, rats subsequently showed a reduced stepping force of the affected limb for at least the next 18 days. The reduced stepping force of the limb was presumably due to a painful knee, since oral injection of indomethacin produced temporary improvement of weight bearing. DBPT dissolved in water was orally administrated. After the treatment, behavioral tests measuring stepping force were periodically conducted during the next 4 hours. DBPT produce significant improvement of stepping force of the hindlimb affected by the arthritis lasting at least 3 hours. The magnitude of this improvement was equivalent to that obtained after an oral injection of 3mg/kg of indomethacin and this improvement of stepping force was interpreted as an analgesic effect. The reduced stepping force was divided into three stages(10-30g, 30-50g, and 50-70g). All experiments was performed at 50-70g of stepping force, since both DBPT and indomethacin showed the most excellent analgesic effect at 50-70g of stepping force. DBPT produced the improvement of stepping force of the affected hindlimb in a dose-dependent manner and showed analgesic effect on neuropathic pain as well. DBPT-induced analgesic effect could not be blocked by systemic injection of steroid antagonist mifepristone. The present study suggest 1) that DBPT produces a potent analgesic effect on the chronic knee arthritis pain model in the rat and 2) that steroids system does not mediate DBPT-induced analgesia.