A5046586634- Force Microscopy Techniques and Applications
- Microstructure and mechanical properties
- Molecular Junctions and Nanostructures
- Graphene research and applications
- Thermal properties of materials
- Advanced biosensing and bioanalysis techniques
- Theoretical and Computational Physics
- DNA and Nucleic Acid Chemistry
- Advanced Thermodynamics and Statistical Mechanics
- Carbon Nanotubes in Composites
- Hydrogen Storage and Materials
- DNA Repair Mechanisms
- Diamond and Carbon-based Materials Research
- Material Dynamics and Properties
- Composite Material Mechanics
- Earth Systems and Cosmic Evolution
- Surface and Thin Film Phenomena
- Radiation Therapy and Dosimetry
- RNA and protein synthesis mechanisms
- Advanced ceramic materials synthesis
- Semiconductor materials and interfaces
- RNA Interference and Gene Delivery
- Nanowire Synthesis and Applications
- Advanced Chemical Physics Studies
- Semiconductor materials and devices
Institut d'électronique de microélectronique et de nanotechnologie
2016-2025
Centre National de la Recherche Scientifique
2016-2025
Université de Lille
2016-2025
Université Polytechnique Hauts-de-France
2016-2024
École Centrale de Lille
2014-2024
Institut d'Électronique et des Systèmes
2017
The University of Tokyo
2015
Laboratory for Integrated Micro-Mechatronic Systems
2015
Centre de Gestion Scientifique
2013
University of Cagliari
2012
The parameters of many-body potentials for fcc and hcp transition metals, based on the second-moment approximation a tight-binding Hamiltonian, have been systematically evaluated. potential scheme, cast in analytical form, allows us to reproduce correctly thermal behavior metals making use small set adjustable parameters. large cutoff, which extends range interactions up fifth-neighbor distance, ensures good quantitative agreement with experimental data temperatures close melting point....
Thermal conductivity (kappa) of isolated carbon nanotubes (CNTs) is higher than the kappa diamond; however, in this Letter we show that a packed bed three-dimensional random networks single and multiwall CNTs smaller thermally insulating amorphous polymers. The thermoelectric power (Sigma) network was also measured. Sigma wall nanotube very similar to and, contrast with kappa, shows strong dependence on tube diameter.
We use molecular dynamics simulations to study the thermal transport properties of a range poor good conductors by method in which two portions are delimited and heated at different temperatures before approach-to-equilibrium whole structure is monitored. The numerical results compared corresponding solution heat equation. Based on this comparison, observed exponential decay temperature difference interpreted used extract conductivity homogeneous materials. first applied bulk silicon an...
Uracil-DNA glycosylase (UDG) is the first enzyme in base-excision repair (BER) pathway, acting on uracil bases DNA. How UDG finds its targets has not been conclusively resolved yet. Based available structural and other experimental evidence, two possible pathways are under discussion. In one, action of DNA believed to follow a 'pinch-push-pull' model, which generates base-flip an active manner. A second scenario based exploitation flipping out thermally from Recent molecular dynamics (MD)...
The DNA base-excision repair (BER) pathway shares the second part of its enzymatic chain with single-strand break (SSB) pathway. BER is initiated by a glycosylase, such as UDG, while SSBR multifunctional enzyme PARP1. very early steps in identification damage are crucial to correct initiation chains, and become even more complex when considering realistic environment nucleosome. We performed molecular dynamics computer simulations interaction between glycosylase UDG mutated uracil (as...
By isolating the process of dislocation emission from a crack tip under an applied tensile stress, we extract molecular dynamics simulation atomic-level displacement and stress fields on activated slip plane before after nucleation event. The stress-displacement relations so obtained provide direct link with recent continuum descriptions brittle versus ductile behavior in propagation. Crack-tip shielding by emitted dislocations is demonstrated, as role surface steps crack-tip blunting.
We use molecular dynamics simulations to study the heat transfer at interface between crystalline Si and amorphous silica. In order quantify thermal boundary resistance, we compare results of two simulation methods: one in which apply a stationary gradient across interface, trying extract resistance from temperature jump; other based on exponential approach equilibrium, by monitoring relaxation times flux exchanged interface. Si/amorphous vs. silica interfaces assess relative importance...
Stretching experiments on single molecules of arbitrary length opened the way for studying statistical mechanics small systems. In many cases in which thermodynamic limit is not satisfied, different macroscopic boundary conditions, corresponding to ensembles, yield force-displacement curves. We formulate analytical expressions and develop Monte Carlo simulations quantitatively evaluate difference between Helmholtz Gibbs ensembles a wide range polymer models biological relevance. consider...
The length dependence of the thermal conductivity over more than two decades is systematically studied for a range materials, interatomic potentials and temperatures, by atomistic approach-to-equilibrium molecular dynamics method (AEMD). By comparing values obtained given supercell maximum phonon mean-free-path (MFP), we find that such are strongly correlated, demonstrating AEMD calculation with finite length, actually probes corresponding to MFP. As consequence, less pronounced usually...
DNA aptamers are versatile molecular species obtained by the folding of short single-stranded nucleotide sequences, with highly specific recognition capabilities against proteins. Here we test ability selected in interacting spike (S-)protein SARS-CoV-2 viral capsid. The S-protein, a trimer made up several subdomains, develops crucial function recognizing ACE2 receptors on surface human cells, and sub- sequent fusioning virus membrane host cell membrane. In order to do this, S1 domain one...
We investigate the physical meaning of intrinsic crack resistance in Griffith theory brittle fracture by means atomic-scale simulations. By taking cubic SiC as a typical material, we show that widely accepted identification with free surface energy underestimates energy-release rate. The strain dependence Young modulus and energy, well allowance for lattice trapping, improve estimate resistance. In smallest scale limit, can be fitted an empirical elastoplastic model.
The macroscopic fracture response of real materials originates from the competition and interplay several atomic‐scale mechanisms decohesion shear, such as inter‐planar cleavage dislocation nucleation motion. These phenomena involve processes over a wide range length scales, atomic to macroscopic. We briefly review attempts span these scales in modeling by (1) fully atomistic large‐scale simulations millions atoms or more, approaching continuum limit “bottom‐up”; (2) directly coupling...
High-density packing in organic crystals is usually associated with an increase of the coordination between molecules. Such a concept not necessarily extended to two-dimensional molecular networks self-assembled on solid surface, for which we demonstrate key role surface inducing optimal packing. By combination scanning tunneling microscopy experiments and multiscale computer simulations, study phase transition two polymorphs. We find that, contrary intuition, structure lowest fraction...
ABSTRACT The DNA base-excision repair (BER) pathway is initiated by a glycosylase, such as UDG, which identifies and removes wrong base incorporated in the sequence. very early steps identification of damage are crucial to correct initiation chain, become even more complex when considering realistic environment nucleosome. We performed all-atom docking molecular dynamics computer simulations interaction between glycosylase UDG mutated uracil. model system whole nucleosome inserted at various...
In a large number of experiments it is observed that the electrical conductivity percolating networks increases with filling, $p,$ as $(p\ensuremath{-}{p}_{c}{)}^{2},$ where ${p}_{c}$ percolation threshold over very broad range $p$ values. Our Monte Carlo simulations, however, suggest this power law will only be valid for $p<{2p}_{c},$ crossover to scaling exponent 1 higher To resolve discrepancy we postulate are dominated by contact resistance, and in case show threshold-scaling 2 holds an...
We present a statistical mechanics analysis of the finite-size elasticity model polymers, consisting domains that can exhibit transitions between more than one stable state at large applied force. The constant-force (Gibbs) and constant-displacement (Helmholtz) formulations single-molecule stretching experiments are shown to converge in thermodynamic limit. Monte Carlo simulations continuous three-dimensional polymers variable length carried out, based on this formulation. demonstrate...
Recent developments of microscopic mechanical experiments allow the manipulation individual polymer molecules in two main ways: uniform stretching by external forces and non-uniform fields. Many results can be thereby obtained for specific kinds polymers geometries. In this work, we describe a single, non-branched molecule an field (e.g., fluid motion, or electric field) universal physical framework, which leads to general conclusions on different types polymers. We derive analytical both...
A transient thermal regime is achieved in glassy GeTe4 by first-principles molecular dynamics following the recently proposed "approach-to-equilibrium" methodology. The temporal and spatial evolution of temperature do comply with time-dependent solution heat equation. We demonstrate that time scales required to create hot cold parts system observe resulting approach equilibrium are accessible dynamics. Such a strategy provides conductivity from characteristic decay time. rationalize detail...
A rare but severe complication of curative-intent radiation therapy is the induction second primary cancers. These cancers preferentially develop not inside planning target volume (PTV) around, over several centimeters, after a latency period 1-40 years. We show here that normal human or mouse dermal fibroblasts submitted to out-of-field dose scattering at margin PTV receiving mimicked patient's treatment do die enter in long-lived senescent state resulting from accumulation unrepaired DNA...
The DNA single-strand break (SSB) repair pathway is initiated by the multifunctional enzyme PARP-1, which recognizes broken ends its two zinc-finger domains, Zn1 and Zn2. Despite a number of experiments performed with different configurations reduced fragments many details this interaction that crucial to correct initiation chain are still unclear. We Molecular Dynamics (MD) computer simulations between Zn1/Zn2 domains PARP-1 hairpin including missing nucleotide simulate presence an SSB,...
By means of tight-binding molecular dynamics simulations we find that the ground-state atomic structure a typical high-energy grain boundary in diamond is highiy disordered with large fraction sp2 bonded atoms. This gives rise to localised bands within band gap. We describe how multiphonon assisted hopping conduction can arise from such electronic states boundaries, giving turn basis for experimentally observed conductivity and electron field emission nanocrystalline diamond. Simulated...