The Experts below are selected from a list of 68112 Experts worldwide ranked by ideXlab platform
J A Mccammon - One of the best experts on this subject based on the ideXlab platform.
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predicting the influence of long range molecular interactions on Macroscopic Scale diffusion by homogenization of the smoluchowski equation
Journal of Chemical Physics, 2014Co-Authors: Peter M Kekeneshuskey, Andrew Gillette, J A MccammonAbstract:The Macroscopic diffusion constant for a charged diffuser is in part dependent on (1) the volume excluded by solute “obstacles” and (2) long-range interactions between those obstacles and the diffuser. Increasing excluded volume reduces transport of the diffuser, while long-range interactions can either increase or decrease diffusivity, depending on the nature of the potential. We previously demonstrated [P. M. Kekenes-Huskey , Biophys. J. 105, 2130 (2013)] using homogenization theory that the configuration of molecular-Scale obstacles can both hinder diffusion and induce diffusional anisotropy for small ions. As the density of molecular obstacles increases, van der Waals (vdW) and electrostatic interactions between obstacle and a diffuser become significant and can strongly influence the latter's diffusivity, which was neglected in our original model. Here, we extend this methodology to include a fixed (time-independent) potential of mean force, through homogenization of the Smoluchowski equation. We consider the diffusion of ions in crowded, hydrophilic environments at physiological ionic strengths and find that electrostatic and vdW interactions can enhance or depress effective diffusion rates for attractive or repulsive forces, respectively. Additionally, we show that the observed diffusion rate may be reduced independent of non-specific electrostatic and vdW interactions by treating obstacles that exhibit specific binding interactions as “buffers” that absorb free diffusers. Finally, we demonstrate that effective diffusion rates are sensitive to distribution of surface charge on a globular protein, Troponin C, suggesting that the use of molecular structures with atomistic-Scale resolution can account for electrostatic influences on substrate transport. This approach offers new insight into the influence of molecular-Scale, long-range interactions on transport of charged species, particularly for diffusion-influenced signaling events occurring in crowded cellular environments.
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predicting the influence of long range molecular interactions on Macroscopic Scale diffusion by homogenization of the smoluchowski equation
Journal of Chemical Physics, 2014Co-Authors: Peter M Kekeneshuskey, Andrew Gillette, J A MccammonAbstract:The Macroscopic diffusion constant for a charged diffuser is in part dependent on (1) the volume excluded by solute "obstacles" and (2) long-range interactions between those obstacles and the diffuser. Increasing excluded volume reduces transport of the diffuser, while long-range interactions can either increase or decrease diffusivity, depending on the nature of the potential. We previously demonstrated [P. M. Kekenes-Huskey et al., Biophys. J. 105, 2130 (2013)] using homogenization theory that the configuration of molecular-Scale obstacles can both hinder diffusion and induce diffusional anisotropy for small ions. As the density of molecular obstacles increases, van der Waals (vdW) and electrostatic interactions between obstacle and a diffuser become significant and can strongly influence the latter's diffusivity, which was neglected in our original model. Here, we extend this methodology to include a fixed (time-independent) potential of mean force, through homogenization of the Smoluchowski equation. We consider the diffusion of ions in crowded, hydrophilic environments at physiological ionic strengths and find that electrostatic and vdW interactions can enhance or depress effective diffusion rates for attractive or repulsive forces, respectively. Additionally, we show that the observed diffusion rate may be reduced independent of non-specific electrostatic and vdW interactions by treating obstacles that exhibit specific binding interactions as "buffers" that absorb free diffusers. Finally, we demonstrate that effective diffusion rates are sensitive to distribution of surface charge on a globular protein, Troponin C, suggesting that the use of molecular structures with atomistic-Scale resolution can account for electrostatic influences on substrate transport. This approach offers new insight into the influence of molecular-Scale, long-range interactions on transport of charged species, particularly for diffusion-influenced signaling events occurring in crowded cellular environments.
Erwan Verron - One of the best experts on this subject based on the ideXlab platform.
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Fatigue damage in carbon black filled natural rubber under uni- and multiaxial loading conditions
International Journal of Fatigue, 2013Co-Authors: Jean-benoit Le Cam, Bertrand Huneau, Erwan VerronAbstract:This paper deals with fatigue damage in carbon black filled natural rubber under uni- and multiaxial loading conditions. Fatigue damage is described at both the Macroscopic (mechanical) Scale and the microscopic (material) Scale. The different fatigue damages observed at the Macroscopic Scale are presented according to the prescribed loading conditions. At this Scale, five elementary fatigue damage patterns are defined, three correspond to external Macroscopic cracks and two correspond to internal Macroscopic cracks. These elementary fatigue damage patterns are investigated at the microscopic Scale by distinguishing crack initiation and crack growth. Results show that the cracks initiate from microstructural defects, whose mean diameter does not exceed 400 mu m and that crack initiation at the Macroscopic Scale corresponds to crack growth at the microscopic Scale, which validates recent energetic approaches adopted to predict fatigue crack initiation in rubbers. The morphology of fracture surfaces exhibits two types of features: wrenchings and fatigue striations. In particular, results highlight that several shapes of fatigue striations can form, depending on the loading conditions, and that several mechanisms of fatigue striation formation could come into play.
Peter M Kekeneshuskey - One of the best experts on this subject based on the ideXlab platform.
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predicting the influence of long range molecular interactions on Macroscopic Scale diffusion by homogenization of the smoluchowski equation
Journal of Chemical Physics, 2014Co-Authors: Peter M Kekeneshuskey, Andrew Gillette, J A MccammonAbstract:The Macroscopic diffusion constant for a charged diffuser is in part dependent on (1) the volume excluded by solute “obstacles” and (2) long-range interactions between those obstacles and the diffuser. Increasing excluded volume reduces transport of the diffuser, while long-range interactions can either increase or decrease diffusivity, depending on the nature of the potential. We previously demonstrated [P. M. Kekenes-Huskey , Biophys. J. 105, 2130 (2013)] using homogenization theory that the configuration of molecular-Scale obstacles can both hinder diffusion and induce diffusional anisotropy for small ions. As the density of molecular obstacles increases, van der Waals (vdW) and electrostatic interactions between obstacle and a diffuser become significant and can strongly influence the latter's diffusivity, which was neglected in our original model. Here, we extend this methodology to include a fixed (time-independent) potential of mean force, through homogenization of the Smoluchowski equation. We consider the diffusion of ions in crowded, hydrophilic environments at physiological ionic strengths and find that electrostatic and vdW interactions can enhance or depress effective diffusion rates for attractive or repulsive forces, respectively. Additionally, we show that the observed diffusion rate may be reduced independent of non-specific electrostatic and vdW interactions by treating obstacles that exhibit specific binding interactions as “buffers” that absorb free diffusers. Finally, we demonstrate that effective diffusion rates are sensitive to distribution of surface charge on a globular protein, Troponin C, suggesting that the use of molecular structures with atomistic-Scale resolution can account for electrostatic influences on substrate transport. This approach offers new insight into the influence of molecular-Scale, long-range interactions on transport of charged species, particularly for diffusion-influenced signaling events occurring in crowded cellular environments.
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predicting the influence of long range molecular interactions on Macroscopic Scale diffusion by homogenization of the smoluchowski equation
Journal of Chemical Physics, 2014Co-Authors: Peter M Kekeneshuskey, Andrew Gillette, J A MccammonAbstract:The Macroscopic diffusion constant for a charged diffuser is in part dependent on (1) the volume excluded by solute "obstacles" and (2) long-range interactions between those obstacles and the diffuser. Increasing excluded volume reduces transport of the diffuser, while long-range interactions can either increase or decrease diffusivity, depending on the nature of the potential. We previously demonstrated [P. M. Kekenes-Huskey et al., Biophys. J. 105, 2130 (2013)] using homogenization theory that the configuration of molecular-Scale obstacles can both hinder diffusion and induce diffusional anisotropy for small ions. As the density of molecular obstacles increases, van der Waals (vdW) and electrostatic interactions between obstacle and a diffuser become significant and can strongly influence the latter's diffusivity, which was neglected in our original model. Here, we extend this methodology to include a fixed (time-independent) potential of mean force, through homogenization of the Smoluchowski equation. We consider the diffusion of ions in crowded, hydrophilic environments at physiological ionic strengths and find that electrostatic and vdW interactions can enhance or depress effective diffusion rates for attractive or repulsive forces, respectively. Additionally, we show that the observed diffusion rate may be reduced independent of non-specific electrostatic and vdW interactions by treating obstacles that exhibit specific binding interactions as "buffers" that absorb free diffusers. Finally, we demonstrate that effective diffusion rates are sensitive to distribution of surface charge on a globular protein, Troponin C, suggesting that the use of molecular structures with atomistic-Scale resolution can account for electrostatic influences on substrate transport. This approach offers new insight into the influence of molecular-Scale, long-range interactions on transport of charged species, particularly for diffusion-influenced signaling events occurring in crowded cellular environments.
Jean-benoit Le Cam - One of the best experts on this subject based on the ideXlab platform.
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Fatigue damage in carbon black filled natural rubber under uni- and multiaxial loading conditions
International Journal of Fatigue, 2013Co-Authors: Jean-benoit Le Cam, Bertrand Huneau, Erwan VerronAbstract:This paper deals with fatigue damage in carbon black filled natural rubber under uni- and multiaxial loading conditions. Fatigue damage is described at both the Macroscopic (mechanical) Scale and the microscopic (material) Scale. The different fatigue damages observed at the Macroscopic Scale are presented according to the prescribed loading conditions. At this Scale, five elementary fatigue damage patterns are defined, three correspond to external Macroscopic cracks and two correspond to internal Macroscopic cracks. These elementary fatigue damage patterns are investigated at the microscopic Scale by distinguishing crack initiation and crack growth. Results show that the cracks initiate from microstructural defects, whose mean diameter does not exceed 400 mu m and that crack initiation at the Macroscopic Scale corresponds to crack growth at the microscopic Scale, which validates recent energetic approaches adopted to predict fatigue crack initiation in rubbers. The morphology of fracture surfaces exhibits two types of features: wrenchings and fatigue striations. In particular, results highlight that several shapes of fatigue striations can form, depending on the loading conditions, and that several mechanisms of fatigue striation formation could come into play.
Andrew Gillette - One of the best experts on this subject based on the ideXlab platform.
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predicting the influence of long range molecular interactions on Macroscopic Scale diffusion by homogenization of the smoluchowski equation
Journal of Chemical Physics, 2014Co-Authors: Peter M Kekeneshuskey, Andrew Gillette, J A MccammonAbstract:The Macroscopic diffusion constant for a charged diffuser is in part dependent on (1) the volume excluded by solute “obstacles” and (2) long-range interactions between those obstacles and the diffuser. Increasing excluded volume reduces transport of the diffuser, while long-range interactions can either increase or decrease diffusivity, depending on the nature of the potential. We previously demonstrated [P. M. Kekenes-Huskey , Biophys. J. 105, 2130 (2013)] using homogenization theory that the configuration of molecular-Scale obstacles can both hinder diffusion and induce diffusional anisotropy for small ions. As the density of molecular obstacles increases, van der Waals (vdW) and electrostatic interactions between obstacle and a diffuser become significant and can strongly influence the latter's diffusivity, which was neglected in our original model. Here, we extend this methodology to include a fixed (time-independent) potential of mean force, through homogenization of the Smoluchowski equation. We consider the diffusion of ions in crowded, hydrophilic environments at physiological ionic strengths and find that electrostatic and vdW interactions can enhance or depress effective diffusion rates for attractive or repulsive forces, respectively. Additionally, we show that the observed diffusion rate may be reduced independent of non-specific electrostatic and vdW interactions by treating obstacles that exhibit specific binding interactions as “buffers” that absorb free diffusers. Finally, we demonstrate that effective diffusion rates are sensitive to distribution of surface charge on a globular protein, Troponin C, suggesting that the use of molecular structures with atomistic-Scale resolution can account for electrostatic influences on substrate transport. This approach offers new insight into the influence of molecular-Scale, long-range interactions on transport of charged species, particularly for diffusion-influenced signaling events occurring in crowded cellular environments.
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predicting the influence of long range molecular interactions on Macroscopic Scale diffusion by homogenization of the smoluchowski equation
Journal of Chemical Physics, 2014Co-Authors: Peter M Kekeneshuskey, Andrew Gillette, J A MccammonAbstract:The Macroscopic diffusion constant for a charged diffuser is in part dependent on (1) the volume excluded by solute "obstacles" and (2) long-range interactions between those obstacles and the diffuser. Increasing excluded volume reduces transport of the diffuser, while long-range interactions can either increase or decrease diffusivity, depending on the nature of the potential. We previously demonstrated [P. M. Kekenes-Huskey et al., Biophys. J. 105, 2130 (2013)] using homogenization theory that the configuration of molecular-Scale obstacles can both hinder diffusion and induce diffusional anisotropy for small ions. As the density of molecular obstacles increases, van der Waals (vdW) and electrostatic interactions between obstacle and a diffuser become significant and can strongly influence the latter's diffusivity, which was neglected in our original model. Here, we extend this methodology to include a fixed (time-independent) potential of mean force, through homogenization of the Smoluchowski equation. We consider the diffusion of ions in crowded, hydrophilic environments at physiological ionic strengths and find that electrostatic and vdW interactions can enhance or depress effective diffusion rates for attractive or repulsive forces, respectively. Additionally, we show that the observed diffusion rate may be reduced independent of non-specific electrostatic and vdW interactions by treating obstacles that exhibit specific binding interactions as "buffers" that absorb free diffusers. Finally, we demonstrate that effective diffusion rates are sensitive to distribution of surface charge on a globular protein, Troponin C, suggesting that the use of molecular structures with atomistic-Scale resolution can account for electrostatic influences on substrate transport. This approach offers new insight into the influence of molecular-Scale, long-range interactions on transport of charged species, particularly for diffusion-influenced signaling events occurring in crowded cellular environments.
