Analysis of the number of topological defects in active nematic fluids under applied shear flow Zhenna Li, Hao Ye, Jianzhong Lin and Zhenyu Ouyang Eur. Phys. J. E, 47 6 (2024) 43 Published online: 20 June 2024 DOI: 10.1140/epje/s10189-024-00437-4