以旋轉Kelvin Voigt model探討血球變形及履帶運動

Investigation of cellular deformation and tank-tread motion with the rotating Kelvin Voigt model

李崑銘(Kun-Ming Lee)

指導教授 ： 陳恕行 ； 林明哲 ； 林穀欽

崑山科技大學/工程學院/機械工程研究所/碩士(2006年)

摘要

生物細胞的黏彈性從被稱為細胞骨骼的密緻蛋白質中獲得，黏彈性使得細胞能維持其結構的完整。黏性主要從細胞質獲得，而彈性是從細胞薄膜獲得。本文為探討血球細胞在有無履帶運動時的變形情況，藉以了解細胞的流變性質與蛋白質的功能。
血液流動時，紅血球會向血管軸心集中流動，並產生變形及旋轉，這種運動方式，使得紅血球很容易變形而適應外部流場，減小血球對流場的干擾，從而使流動阻力降低，方便能夠穿梭於血管中。
白血球與紅血球不同，白血球的變形是一種複雜的被動運動，流動的白血球在剪應力的作用下，不僅出現隨流線拉長與取向而且還伴有旋轉。白血球旋轉時，首先是薄膜在剪應力作用下旋轉，然後帶動胞漿旋轉，類似如坦克車履帶的運動方式。
本研究使用旋轉Kelvin Voigt model模擬細胞變形以及血球受力情形，使用程式模擬細胞在有無履帶運動時，其細胞的變形和運動。

關鍵字

黏彈性 ； 履帶運動 ； 細胞骨骼

並列摘要

Biological cells obtain viscoelastic property from elaborate arrays of protein fibers known as cytoskeleton. With this viscoelastic property, a cell maintains its structural integrity and is able to move. Viscous property is obtained from cytoplasm, while the elasticity is obtained from cellular membrane. Cellular deformation and tank-tread motions are simulated with the rotating Kevin-Voigt model.
While traveling, red blood cells like to migrate to the central lumen of the vessel, this phenomenon is known as axial migration of red blood cells. Axial migration will lead to a red cell-free peripheral layer, where white blood cells travel at a much slower speed. This work will investigate the deformation of cells at different radial position within the vessel.
Tank-tread motion can be observed on white blood cells while they crawl on the wall the endothelial surface. A cell may undergo a tank-tread motion when the shear stress exceeds a certain threshold. Tank-tread motions are often observed on a drop of water flowing down an incline. Tank-tread motion is a mechanism to prevent the tumbling of the delicate interior of a cell.
To better understand the motions of red cells and white cells, a rotating Kelvin Voigt model is used to simulate the rotating motions.

並列關鍵字

cytoskeleton ； tank-tread motion ； viscoelastic

參考文獻

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