标题： 向列型液晶弹性性质由活细胞形成并迁移所产生 显示英文标题

标题： Elastic Properties of Nematic Liquid Crystals Formed by Living and Migrating Cells

摘要： 在迁移和相互作用的变形细胞的培养物中可以形成向列型液晶相。 如果相互作用具有极性对称性，则会形成极性向列型液晶。 一种白细胞（粒细胞）形成簇，其中细胞朝向中心。 这种取向缺陷（位错）的核心要么是被迫处于各向同态状态的粒细胞，要么是另一种细胞类型，如单核细胞。 如果相互作用具有非极性对称性，则会形成非极性向列型液晶。 不同类型的细胞，如人黑素细胞（=皮肤的色素细胞）、人成纤维细胞（=结缔组织细胞）、人成骨细胞（=骨细胞）、人脂肪细胞（=脂肪细胞）等，形成非极性向列型液晶。 推导了取向弹性能量，并研究了向列型液晶的取向缺陷（位错）。 半整数位错的存在表明向列相具有非极性对称性。 估计了取向弹性常数及其绝对值对密度和有序参数的依赖关系。 从缺陷结构中发现，展曲弹性常数小于弯曲弹性常数（黑素细胞）。 位错的核心要么是无细胞的空间，要么被无取向的细胞（各向同性相）占据，要么被具有不同对称性的细胞占据，要么被另一种细胞类型占据。 显示英文摘要

摘要： In culture migrating and interacting amoeboid cells can form nematic liquid crystal phases. A polar nematic liquid crystal is formed if the interaction has a polar symmetry. One type of white blood cells (granulocytes) form clusters where the cells are oriented towards the center. The core of such an orientational defect (disclination) is either a granulocyte forced to be in an isotropic state or another cell type like a monocyte. An apolar nematic liquid crystal is formed if the interaction has an apolar symmetry. Different cell types like human melanocytes (=pigment cells of the skin), human fibroblasts (=connective tissue cells), human osteoblasts (=bone cells), human adipocytes (= fat cells) etc., form an apolar nematic liquid crystal. The orientational elastic energy is derived and the orientational defects (disclination) of nematic liquid crystals are investigated. The existence of half-numbered disclinations show that the nematic phase has an apolar symmetry. The density- and order parameter dependence of the orientational elastic constants and their absolute values are estimated. From the defect structure, one finds that the splay elastic constant is smaller than the bend elastic constant (melanocytes). The core of a disclination is either a cell free space or occupied by non oriented cells (isotropic phase) or occupied by a cell with a different symmetry or occupied by another cell type.