Arteries display highly directional growth and remodeling that are specific to increases in the mechanical loads imposed on them by blood pressure, blood flow, and lengthwise tensile forces that are transmitted from the tissues to which they are attached. This study examined the effect of mechanical forces on the direction in which mitosis delivers daughter cells, as a mechanism for directional...

An approach to the dynamic analysis of parallel manipulators is presented. The proposed method, based on the theory of screws and on the principle of virtual work, allows a straightforward calculation of the actuator forces as a function of the external applied forces and the imposed trajectory. In order to show the generality of such a methodology, two case studies are developed, a 2-DOF paral...

It is not known which kinetic step in the acto-myosin ATPase cycle limits contraction speed in unloaded muscles (V0). Huxley's 1957 model [Huxley AF (1957) Prog Biophys Biophys Chem 7:255-318] predicts that V0 is limited by the rate that myosin detaches from actin. However, this does not explain why, as observed by Bárány [Bárány M (1967) J Gen Physiol 50(6, Suppl):197-218], V0 is linearly corr...

Plants growing in rivers and lakes experience drag forces imposed by flowing water. In order to reduce the drag, plants reconfigure and streamline themselves at multiple scales. The ability of plants to reconfigure depends on their morphological and bio-mechanical properties. The plant leaves play an important role in this process which is still to be better defined and quantified. Therefore, t...

Structure formation in response to flow is common in soft materials and complex fluids and is dependent on the nature of the cohesive forces in the system, timescales for diffusive motions and hydrodynamic interactions. For Brownian systems with hard sphere or repulsive interactions, distortion of the microstructure due to an imposed shear rate occurs when the timescale for flow is smaller than...

Concrete guideways for proposed MAGLEV vehicles may be reinforced with electrically conducting and magnetizable steel rebars. Transient magnetic fields due to passing MAGLEV vehicles will then induce transient currents in the rebars leading to power dissipation and temperature rise as well as Lorentz and magnetization forces on the rebars. In order to evaluate if this heating and force on the r...

Orientation of the division axis can determine cell fate in the presence of morphogenetic gradients. Understanding how mitotic cells integrate directional cues is therefore an important question in embryogenesis. Here, we investigate the effect of dynamic shear forces on confined mitotic cells. We found that human epithelial cells (hTERT-RPE1) as well as MC3T3 osteoblasts align their mitotic sp...

Soft matter deforms in response to imposed external forces. Here we demonstrate how dynamic surface forces are linked to far-field deformations. This offers a new paradigm for determining forces between soft particles in colloidal systems. The particular example we use to illustrate this concept is that of a fluid drop interacting with a solid wall through hydrodynamic drainage flow coupled wit...

We show that artificial language evolution involves the interplay of two opposing forces: pressure toward simple representations imposed by the dynamics of collective learning, and pressure towards complex representations imposed by requirements of agents’ tasks. The push-pull of these two forces results in the emergence of a language that is balanced: “simple but not too simple.” We introduce ...