Background The role of calcium in physiological phenomenona such as sperm acrosome reaction and hyper-activation has been well known. Calcium ionophore A23187 is routinely used for induction of acrosome reaction in mammalians sperm. Therefore, we decided to evaluate the effect of calcium ionophore A23187 on the sperm hyper-active motility patterns. MaterialsAndMethods Ten semen samples from ind...

Performing large-scale simulations of active particles and employing finite-size-scaling analysis, we provide exhaustive evidence that motility-induced critical point belongs to the Ising universality class.

Drops of active liquid crystal have recently shown the ability to self-propel, which was associated with topological defects in the orientation of active filaments [Sanchez et al., Nature 491, 431 (2013)]. Here, we study the onset and different aspects of motility of a three-dimensional drop of active fluid on a planar surface. We analyze theoretically how motility is affected by orientation pr...

We develop a model of amoeboid cell motility based on active gel theory. Modeling the motile apparatus of a eukaryotic cell as a confined layer of finite length of poroelastic active gel permeated by a solvent, we first show that, due to active stress and gel turnover, an initially static and homogeneous layer can undergo a contractile-type instability to a polarized moving state in which the r...

We demonstrate that deep learning techniques can be used to predict motility-induced phase separation (MIPS) in suspensions of active Brownian particles (ABPs) by creating a notion at the particle level.

Active nematic droplets on surfaces are studied at different activities a wide range of surfaces. The analysis provides global description the dynamical regimes reported for active droplets, such as wetting, propulsion, and chaotic motion, it reveals dimensionless parameters that characterize dynamics

Understanding flow and transport of bacteria in porous media is crucial to technologies such as bioremediation, biomineralization or enhanced oil recovery. While physicochemical filtration well-documented, recent studies showed that bacterial motility plays a key role the process. Flow experiments performed microfluidic chips containing randomly placed obstacles confirmed distributions non-moti...

The objectives of this study were to determine if human ejaculated sperm exhibit active caspases and if caspase-dependent apoptosis markers are identifiable. Sperm from fertile donors and infertile patients were examined after gradient separation into leukocyte-free fractions of high and low motility. Sperm were evaluated for motion parameters, morphology, caspase activation, and apoptosis mark...