Zhang He-Peng (张何朋)a, Liu Bin (刘斌)b, Bruce Rodenbornc, Harry L. Swinneyc
a Department of Physics and Astronomy and Institute of Natural Sciences, Shanghai Jiao Tong University, Shanghai, China;
b School of Natural Sciences, University of California, Merced, California, USA;
c Department of Physics and Center for Nonlinear Dynamics, University of Texas at Austin, Austin, Texas, USA
We study the propulsion matrix of bacterial flagella numerically using slender body theory and the regularized Stokeslet method in a biologically relevant parameter regime. All three independent elements of the matrix are measured by computing propulsive force and torque generated by a rotating flagellum, and the drag force on a translating flagellum. Numerical results are compared with the predictions of resistive force theory, which is often used to interpret micro-organism propulsion. Neglecting hydrodynamic interactions between different parts of a flagellum in resistive force theory leads to both qualitative and quantitative discrepancies between the theoretical prediction of resistive force theory and the numerical results. We improve the original theory by empirically incorporating the effects of hydrodynamic interactions and propose new expressions for propulsive matrix elements that are accurate over the parameter regime explored.
Project supported by the National Natural Science Foundation of China (Grant No. 11104179), the Shanghai Pujiang Program, China (Grant No. 12PJ1405400), the Program for Professor of Special Appointment (Eastern Scholar) at Shanghai Institutions of Higher Learning, China (Grant No. SHDP201301), and the Innovation Program of Shanghai Municipal Education Commission, China (Grant No. 14ZZ030).
Altmetric calculates a score based on the online attention an article receives. Each coloured thread in the circle represents a different type of online attention. The number in the centre is the Altmetric score. Social media and mainstream news media are the main sources that calculate the score. Reference managers such as Mendeley are also tracked but do not contribute to the score. Older articles often score higher because they have had more time to get noticed. To account for this, Altmetric has included the context data for other articles of a similar age.
