相关论文: Fluctuations of a membrane nanotube covered with a…
Living cells exhibit an important out-of-equilibrium mechanical activity, mainly due to the forces generated by molecular motors. These motor proteins, acting individually or collectively on the cytoskeleton, contribute to the violation of…
Constancy of life vitally depends on the internalization of particles through biomembranes. Of particular interest, cellular uptake, including phagocytosis, receptor-mediated endocytosis, and membrane fusion, critically depends on the…
Motivated by the mechanics of dynamin-mediated membrane tube fission we analyse the stability of fluid membrane tubes subjected to shear flow in azimuthal direction. We find a novel helical instability driven by the membrane shear flow…
We analyse the thermal fluctuations of magnetization textures in two stray field coupled elements, forming mesospins. To this end, the energy landscape associated with the thermal dynamics of the textures is mapped out and asymmetric energy…
The effect of AC electric fields on the elasticity of supported lipid bilayers has been investigated at the microscopic level using grazing incidence synchrotron x-ray scattering. A strong decrease in the membrane tension up to 1mN/m and a…
Recent experiments in various cell types have shown that two-dimensional tissues often display local nematic order, with evidence of extensile stresses manifest in the dynamics of topological defects. Using a mesoscopic model where tissue…
In the framework of a phase field model of a single cell crawling on a substrate, we investigate how the properties of the cell membrane affect the shape and motility of the cell. Since the membrane influences the cell dynamics on multiple…
We present measurements of the fluctuation spectrum of giant vesicles containing bacteriorhodopsin (BR) pumps using video-microscopy. When the pumps are activated, we observe a significant increase of the fluctuations in the low wavevector…
We have measured the frequency and temperature dependences of complex ac conductivity, \sigma(\omega)=\sigma_1(\omega)-i\sigma_2(\omega), of NbN films in zero magnetic field between 0.1 to 10 GHz using a microwave broadband technique. In…
Membrane tubes (spicules) arise in cells, or artificial membranes, in the nonlinear deformation regime due to, e.g. the growth of microtubules, actin filaments or sickle hemoglobin fibers towards a membrane. We calculate the axial force…
The function of membrane-embedded proteins such as ion channels depends crucially on their conformation. We demonstrate how conformational changes in asymmetric membrane proteins may be inferred from measurements of their diffusion. Such…
We analyze both the static and dynamic fluctuation spectrum of the red-blood cell in a unified manner, using a simple model of the composite membrane. In this model, the two-dimensional spectrin network that forms the cytoskeleton is…
Membrane deformation inside living cells is crucial for the proper shaping of various intracellular organelles and is necessary during the fission/fusion processes that allow membrane recycling and transport (e.g. endocytosis). Proteins…
Density functional methods have been used to calculate the electronic properties of aligned smalldiameter single-walled carbon nanotubes under hydrostatic pressures. Abrupt pressure induced semiconductor-metal and metal-semiconductor…
The goal of this PhD thesis was to characterize the properties of friction in nanotubes and from a more general point of view the understanding of the microscopic origin of friction. Indeed, the relative simplicity of the system allows us…
Tribological characteristics of nanotube-based nanoelectromechanical systems (NEMS) exemplified by a gigahertz oscillator are studied. Various factors that influence the tribological properties of the nanotube-based NEMS are quantitatively…
Long-scale dynamic fluctuation phenomena in freely suspended films is analyzed. We consider isotropic films that, say, can be pulled from bulk smectic A liquid crystals. The key feature of such objects is possibility of bending deformations…
The plasma membrane of living cells is compartmentalized at multiple spatial scales ranging from the nano- to the meso-scale. This non-random organization is crucial for a large number of cellular functions. At the nanoscale, cell membranes…
The frequency-dependent spectrum of current fluctuations through nano-scale channels is studied using analytical and computational techniques. Using a stochastic Nernst-Planck description and neglecting the interactions between the ions…
The remaining dynamical degrees of freedom of molecular fluids confined into capillaries of nano to sub-nanometer diameter are of fundamental relevance for future developments in the field of nanofluidics. These properties cannot be simply…