PhD Comprehensive Exam | Sepehr Ghadami, Modeling and simulation of sperm in a viscous fluid

MS Teams (please email amgrad@uwaterloo.ca for the meeting link)

Candidate

Sepehr Ghadami | Applied Mathematics, University of Waterloo

Title

Modeling and simulation of sperm in a viscous fluid

Abstract

Infertility is a very significant health concern during the last decades which impact specifically the life of over 70 million couples[43]. The infertility issues are caused mostly by DNA damage, abnormal sperm morphology, low motility and low sperm count [20, 28]. Since 1990, different methods such as assisted reproductive technologies (ARTs) including invitro fertilization (IVF) were used to treat fertility issues in men [7, 44]. Moreover, recently, new methods such as using micro-helices and sperm-bot were proposed for improving the motility of sperm which is one of the main reasons of male infertility [38]. However, different issues was addressed by Mariana et al. for utilizing this method in a clinical setting [38]. Complete release of sperm from the micro helix is one of the practical issues that prevent usage of micro-helix in clinical experiments.

To solve the fertility issues, it is particularly important to improve our knowledge about the physics of sperm motion in different fluid based on its specific morphology. Therefore, in this project, as the first step, motion of sperm in a viscous Newtonian fluid is modeled. Spring model is used to simulate the sperm and regularized stokeslet method is used to model the interaction between the sperm and the fluid. In the next step, as sperms are mostly swimming in a viscoelastic fluid, the developed model for simulating sperm motion in a Newtonian fluid is improved to investigate the motion of sperm in a viscoelastic fluid. In the next step, in this project, the motion of sperm in a viscoelastic fluid is modeled while surrounded by a magnetic micro helix as a one of the feasible method to assist fertilization. In this step also the release of sperm from micro helix in different viscoelastic fluid is modeled to provide some recommendations to improve the process of releasing sperm from the micro helix as one of the most challenging part in this method for being utilized in clinical experiments. In the final step, we will try to improve the developed model for the sperm by using Geometric Clutch hypothesis to simulate the rotation of sperm rotation around its swimming direction for the first time [32].