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Related papers: Permeation as a Diffusion Process

200 papers

We study the effect of intracellular ion diffusion on ionic currents permeating through the cell membrane. Ion flux across the cell membrane is mediated by special proteins forming specific channels. The structure of potassium channels have…

Cell Behavior · Quantitative Biology 2015-02-20 D. Andreucci , D. Bellaveglia , E. N. M. Cirillo , S. Marconi

We consider in this paper a solvable model for the motion of molecular motors. Based on the averaging principle, we reduce the problem to a diffusion process on a graph. We then calculate the effective speed of transportation of these…

Probability · Mathematics 2013-06-11 Mark Freidlin , Wenqing Hu

In this paper we develop a model to describe the diffusion process in a porous medium. For the observed decrease in current yield, we propose other causes than difference in diffusivity, which we consider unaltered by the porous medium. The…

Chemical Physics · Physics 2012-05-10 P. C. T. DÁjello , G. L. Nunes , J. J. Piacentini , L. Lauck

Unassisted ion transport through lipid membranes plays a crucial role in many cell functions without which life would not be possible, yet the precise mechanism behind the process remains unknown due to its molecular complexity. Here, we…

Soft Condensed Matter · Physics 2022-07-25 David Roesel , Maksim Eremchev , Chetan S. Poojari , Jochen S. Hub , Sylvie Roke

Ion channels are proteins with a hole down the middle embedded in cell membranes. Membranes form insulating structures and the channels through them allow and control the movement of charged particles, spherical ions, mostly Na+, K+, Ca++,…

Biomolecules · Quantitative Biology 2015-05-11 Bob Eisenberg

On the basis of a previous theoretical approach to the plastic flow of highly refined materials, a physical explanation for diffusion bonding is essayed, which yields closed--form equations relating the bonding progress with time,…

Materials Science · Physics 2010-07-02 Miguel Lagos , César Retamal

Because of the large mass differences between electrons and ions, the heat diffusion in electron-ion plasmas exhibits more complex behavior than simple heat diffusion found in typical gas mixtures. In particular, heat is diffused in two…

Plasma Physics · Physics 2021-05-12 S. Jin , A. H. Reiman , N. J. Fisch

Particle transport, acceleration and energisation are phenomena of major importance for both space and laboratory plasmas. Despite years of study, an accurate theoretical description of these effects is still lacking. Validating models with…

The movement of ionic solutions is an essential part of biology and technology. Fluidics, from nano- to micro- to microfluidics, is a burgeoning area of technology which is all about the movement of ionic solutions, on various scales. Many…

Quantitative Methods · Quantitative Biology 2018-06-08 Shixin Xu , Bob Eisenberg , Zilong Song , Huaxiong Huang

We propose a method for the theoretical investigation of polymer translocation through composite pore structures possessing arbitrarily specified geometries. Translocation through each constituent part of the composite is treated as being…

Soft Condensed Matter · Physics 2008-03-07 Aruna Mohan , Anatoly B. Kolomeisky , Matteo Pasquali

How many times a diffusing molecule can permeate across a membrane or be adsorbed on a substrate? We employ the encounter-based approach to find the statistics of adsorption or permeation events for molecular diffusion in a general…

Chemical Physics · Physics 2025-07-15 Denis S. Grebenkov

Plasma technology has found widespread applications in numerous domains, yet the techniques to manipulate plasma transport predominantly rely on magnetic control. In this review, we present a streamlined diffusion-migration method to…

Plasma Physics · Physics 2023-09-26 Fubao Yang , Zeren Zhang

In this paper we present a mathematical model for the electrochemical deposition aimed at the production of inverse opals. The real system consists of an arrangement of sub micrometer spheres, through which the species in an electrolytic…

Chemical Physics · Physics 2013-06-25 P. C. T. D'Ajello , L. Lauck , G. L. Nunes

This paper presents a method for shaping the transmit pulse of a molecular signal such that the diffusion channel's response is a sharp pulse. The impulse response of a diffusion channel is typically characterised as having an infinitely…

Emerging Technologies · Computer Science 2016-11-17 Siyi Wang , Weisi Guo , Mark D. McDonnell

We show how active transport of ions can be interpreted as an entropy facilitated process. In this interpretation, the pore geometry through which substrates are transported can give rise to a driving force. This gives a direct link between…

Biomolecules · Quantitative Biology 2017-05-24 J. M. Rubi , A. Lervik , D. Bedeaux , S. Kjelstrup

The translocation dynamics of a polymer chain through a nanopore in the absence of an external driving force is analyzed by means of scaling arguments, fractional calculus, and computer simulations. The problem at hand is mapped on a one…

Soft Condensed Matter · Physics 2007-07-29 J. L. A. Dubbeldam , A. Milchev , V. G. Rostiashvili , T. A. Vilgis

A microscopic theory for cation diffusion in polymer electrolytes is presented. Based on a thorough analysis of molecular dynamics simulations on PEO with LiBF$_4$ the mechanisms of cation dynamics are characterised. Cation jumps between…

Soft Condensed Matter · Physics 2009-11-13 A. Maitra , A. Heuer

In this article we review classical and recent results in anomalous diffusion and provide mechanisms useful for the study of the fundamentals of certain processes, mainly in condensed matter physics, chemistry and biology. Emphasis will be…

Statistical Mechanics · Physics 2019-02-25 Fernando A. Oliveira , Rogelma M. S. Ferreira , Luciano C. Lapas , Mendeli H. Vainstein

Potassium channels play critical roles in many physiological processes, providing a selective permeation route for K+ ions in and out of a cell, by employing a carefully designed selectivity filter, evolutionarily conserved from viruses to…

Biological Physics · Physics 2021-04-16 Andrei Mironenko , Ulrich Zachariae , Bert L. de Groot , Wojciech Kopec

Molecular dynamics simulations are used to study the mechanism and kinetics of hydrated electron diffusion. The electron center of mass is found to exhibit Brownian-type behavior with a diffusion coefficient considerably greater than that…

Chemical Physics · Physics 2012-11-06 Kafui A. Tay , François-Xavier Coudert , Anne Boutin