SPH–DEM coupling method based on GPU and its application to the landslide tsunami. Part II: reproduction of the Vajont landslide tsunami

Acta Geotechnica - Landslide tsunamis are complex fluid–solid coupling processes that often cause enormous catastrophes. In this study, the smooth particle hydrodynamics (SPH) and discrete...     

圆斑星鲽连续性鳃细胞系的建立

为建立圆斑星鲽(Verasper variegatus)鳃细胞系,本文采用胰蛋白酶消化法启动了圆斑星鲽鳃组织的体外培养,并通过对培养液配方和培养条件的优化成功地进行了圆斑星鲽鳃细胞的原代培养和继代培养。结果显示,圆斑星鲽鳃细胞的最适培养液为含有20%胎牛血清(FBS)的DMEM/F-12培养液,培养液最适pH值为7.2,最适培养温度为22℃;通过向20%FBS-DMEM/F-12培养液(pH=7.2)中添加N-乙酰葡萄糖盐酸盐、羧甲基壳寡糖、碱性成纤维细胞生长因子(bFGF)及I型胰岛素样生长因子(IGF-I),在22℃成功启动了圆斑星鲽鳃细胞的原代培养,细胞的贴壁、生长和分裂状态良好,为典型的成纤维样细胞形态,30 d即可形成汇合的细胞单层;经连续继代培养后,已成功建立了连续性圆斑星鲽鳃细胞系,现已继代培养至第76代;该细胞系细胞经液氮冻存复苏后仍保持其原有的成纤维样细胞形态,其贴壁生长状态和增殖速度也与冻存前无差异;生长特性鉴定结果显示,第60代圆斑星鲽鳃细胞系细胞的群体倍增时间为43.6 h,表明细胞的生长分裂依然十分旺盛。染色体分析结果显示,圆斑星鲽鳃细胞系细胞虽然出现了染色体的非整倍性,但其特征性染色体数目仍为46条,并具有其典型的二倍体核型特征(46 t),表明所建立的细胞系确为圆斑星鲽鳃细胞系。该细胞系的建立对于病毒与宿主相互作用机理的研究及病毒疫苗的开发具有重要的理论和应用价值。     

大黄鱼鳍细胞系的建立及久效磷对其毒性作用的研究

为了建市大黄鱼(Pseudosciaena crocea)鳍细胞系,为其细胞毒理学、病毒学与细胞工程等研究奠定基础,本文采用酶消化法使用含有20%胎牛血清(FBS)的DMEM/F12、Leibovitz L-15和DMEM培养液(pH7.2)在22～28℃分别启动了大黄鱼鳍组织的体外培养,通过添加促细胞贴壁和分裂的物质在最适堵养条件下对大黄鱼鳍细胞进行了原代培养和继代培养,并研究了久效磷对大黄鱼细胞系鳍细胞的毒性作用.体外培养结果显示,大黄鱼鳍细胞的最适培养液为20%FBS-DMEM/F12,最适培养温度为25℃,体外培养鳍细胞的形态主要为成纤维细胞样,22 d后便可形成汇合细胞单层,经过连续继代培养成功建立了大黄鱼的连续性鳍细胞系,目前已传至第112代;对第60代大黄鱼鳍细胞系细胞的鉴定结果显示,其群体倍增时间为50.96 h,分裂状态十分旺盛,虽然出现了染色体的非整倍性,但其特征性染色体数目仍为48条,并具有正常的6m+6sm+36t二倍体核型,证明所建立的细胞系确为大黄鱼鳍细胞系.不同浓度久效磷处理的检测结果显示,大黄鱼鳍细胞对久效磷敏感,20～160 μg/mL久效磷可引起鳍细胞乙酰胆碱酯酶活性的持续性显著降低,引起超氧化物歧化酶和谷胱甘肽-S-转移酶活性的显著升高并随着浓度的升高而逐渐降低,久效磷对该细胞系细胞的48 h半抑制浓度(IC50)为43.05 μg/mL,,证实久效磷对大黄鱼鳍细胞具有显著的毒性作用.     

SPH-DEM coupling method based on GPU and its application to the landslide tsunami. Part I: method and validation

Landslide-induced tsunami is a complex fluid–solid coupling process that plays a crucial role in the study of a disaster chain. To simulate the coupling behaviors between the fluid and solid, a graphics processing unit-based coupled smoothed particle hydrodynamics (SPH)-discrete element method (DEM) code is developed. A series of numerical tests, which are based on the laboratory test by Koshizuka et al. (Particle method for calculating splashing of incompressible viscous fluid, 1995) and Kleefsman et al. (J Comput Phys 206:363–393, 2005), are carried out to study the influence of the parameters, and to verify the accuracy of the developed SPH code. To ensure accurate results of the SPH simulation, the values for the diffusion term, particle resolution (1/25 characteristic length), and smoothing length (1.2 times of particle interval) are suggested. The ratio of the SPH particle size and the DEM particle’s diameter influences the accuracy of the coupling simulation between solid particles and water. For the coupling simulation of a single particle or a loose particle assembly (not contact each other) with fluid, this ratio should be smaller than 1/20; for a dense particle assembly, a ratio of smaller than 1/6 will be good.