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Fluorimetric Techniques for the Assessment of Sperm Membranes
Published on: November 28, 2018
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Effect of external shear flow on sperm motility
Manish Kumar1, Arezoo M Ardekani
1School of Mechanical Engineering, Purdue University, West Lafayette, Indiana, 47907, USA. ardekani@purdue.edu.
Soft Matter
|July 20, 2019
Summary
Sperm movement in fluid flow impacts fertilization. This study reveals how shear and Poiseuille flows affect sperm trajectories, influenced by flow rate and sperm flexibility.
Area of Science:
- Biophysics
- Fluid Dynamics
- Reproductive Biology
Background:
- Sperm motility is crucial for fertilization.
- Sperm navigate complex fluid environments with varying flow conditions.
- Understanding sperm trajectory in flow is key to reproductive success.
Purpose of the Study:
- To investigate sperm trajectory dynamics in simple shear flow and Poiseuille flow.
- To analyze the influence of flow parameters and sperm properties on sperm movement.
- To elucidate mechanisms governing sperm navigation in physiological fluid flows.
Main Methods:
- Computational modeling of sperm hydrodynamics.
- Simulation of sperm movement in unbounded simple shear flow.
- Simulation of sperm movement in Poiseuille flow.
Main Results:
- In simple shear flow, sperm follow elliptical paths, with trajectory length decreasing as shear rate increases.
- Sperm flexibility, quantified by the sperm number (viscous to elastic force ratio), influences elliptical trajectory length.
- In Poiseuille flow, sperm exhibit both downstream/upstream movement and cross-stream migration towards the centerline.
- Cross-stream migration velocity is dependent on distance from the centerline and increases with sperm number.
Conclusions:
- Sperm trajectory is significantly altered by background flow characteristics (shear vs. Poiseuille).
- Sperm number is a critical parameter influencing trajectory shape and migration behavior.
- These findings provide insights into sperm navigation strategies in the female reproductive tract.
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