arXiv subjects

Yves-Henri Sanejouand

Publications and source records attributed to Yves-Henri Sanejouand.

22 records · Page 2Linked to original sources

arXiv2007

Discrete breathers in nonlinear network models of proteins

We introduce a topology-based nonlinear network model of protein dynamics with the aim of investigating the interplay of spatial disorder and nonlinearity. We show that spontaneous localization of energy occurs generically and is a site-dependent process. Localized modes of nonlinear origin form spontaneously in the stiffest parts of the structure and display site-dependent activation energies. Our results provide a straightforward way for understanding the recently discovered link between protein local stiffness and enzymatic activity. They strongly suggest that nonlinear phenomena may play an important role in enzyme function, allowing for energy storage during the catalytic process.

q-bio.BM↗

arXiv2005

A simple varying-speed-of-light hypothesis is enough for explaining high-redshift supernovae data

The hypothesis that the speed of light decreases by nearly 2 cm per sec and per year is discussed within the frame of a simple phenomenological model. It is shown that this hypothesis can provide an alternative explanation for the redshift-distance relationship of type Ia supernovae, which is nowadays given in terms of a new form of (dark) energy of unknown origin.

astro-ph↗

arXiv2005

Functional modes of proteins are among the most robust ones

It is shown that a small subset of modes which are likely to be involved in protein functional motions of large amplitude can be determined by retaining the most robust normal modes obtained using different protein models. This result should prove helpful in the context of several applications proposed recently, like for solving difficult molecular replacement problems or for fitting atomic structures into low-resolution electron density maps. Moreover, it may also pave the way for the development of methods allowing to predict such motions accurately.

q-bio.BM↗

arXiv2005

Slow energy relaxation of macromolecules and nano-clusters in solution

Many systems in the realm of nanophysics from both the living and inorganic world display slow relaxation kinetics of energy fluctuations. In this paper we propose a general explanation for such phenomenon, based on the effects of interactions with the solvent. Within a simple harmonic model of the system fluctuations, we demonstrate that the inhomogeneity of coupling to the solvent of the bulk and surface atoms suffices to generate a complex spectrum of decay rates. We show for Myoglobin and for a metal nano-cluster that the result is a complex, non-exponential relaxation dynamics.

cond-mat.stat-mech↗