Journal articles: 'Ion action'

1

Jan, Lily Yeh. "Ion Channels—Molecules in Action." Cell 89, no. 6 (June 1997): 829–30. http://dx.doi.org/10.1016/s0092-8674(00)80267-6.

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Fuchs, I., K. Philippar, and R. Hedrich. "Ion Channels Meet Auxin Action." Plant Biology 8, no. 3 (May 2006): 353–59. http://dx.doi.org/10.1055/s-2006-924121.

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Liu, Mei Jie, Guo Ri Dong, and Ji Bin Wang. "The Effect of Heavy Metal Ion on Microorganism in Activated Sludge." Advanced Materials Research 926-930 (May 2014): 4377–80. http://dx.doi.org/10.4028/www.scientific.net/amr.926-930.4377.

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Aiming at the effect of heavy metal ion on activated sludge microorganism, this paper has concluded predecessor literatures, and analyzed mechanism of action of metal ion to activated sludge microorganism and the effect to microbial growth kinetics. And it has concluded heavy metal ion effluent COD value, SV, SVI and effect of microbial community structure about activated sludge system. And then it has summarized heavy metal ion joint action on activated sludge microorganism, and some effect like pH element to heavy metal toxic actions.

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Brown, Arthur M. "Ion Channels in Action Potential Generation." Hospital Practice 27, no. 10 (October 15, 1992): 125–32. http://dx.doi.org/10.1080/21548331.1992.11705513.

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Kiefer, Jürgen, Mathias Brend'amour, and Uwe Stoll. "Heavy ion action on biological systems." Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 107, no. 1-4 (February 1996): 292–98. http://dx.doi.org/10.1016/0168-583x(95)01035-1.

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Green, Felicia, and Anna Simmonds. "Imaging metabolism in action." Physics World 34, no. 9 (December 1, 2021): 33–36. http://dx.doi.org/10.1088/2058-7058/34/09/30.

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From improving the sensitivity of ion sources to boosting image resolution, Felicia Green and Anna Simmonds unveil the ambitious biological mass spectrometry programme at the Rosalind Franklin Institute to image molecular interactions in tissues.

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Meves, Hans. "The Action of Prostaglandins on Ion Channels." Current Neuropharmacology 4, no. 1 (January 1, 2006): 41–57. http://dx.doi.org/10.2174/157015906775203048.

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Mikheev, S. Yu, I. I. Shkarban, Y. A. Ryzhov, S. A. Khartov, M. M. Gorshkov, and R. P. Markov. "Solid nanomembrane manufacture using ion-plasma action." Russian Aeronautics (Iz VUZ) 55, no. 1 (January 2012): 108–12. http://dx.doi.org/10.3103/s1068799812010175.

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9

LLOYD, MICHAEL. "Divine and Human Action in Euripides’ Ion." Antike und Abendland 32, no. 1 (December 31, 1986): 33–45. http://dx.doi.org/10.1515/9783110241440.33.

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10

Ford, M. "Molecular action of insecticides on ion channels." Endeavour 20, no. 2 (January 1996): 92. http://dx.doi.org/10.1016/0160-9327(96)88426-2.

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11

Sabzpoushan, S. H., and A. Faghani Ghodrat. "Role of Sodium Channel on Cardiac Action Potential." Engineering, Technology & Applied Science Research 2, no. 3 (June 4, 2012): 232–36. http://dx.doi.org/10.48084/etasr.174.

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Sudden cardiac death is a major cause of death worldwide. In most cases, it's caused by abnormal action potential propagation that leads to cardiac arrhythmia. The aim of this article is to study the abnormal action potential propagation through sodium ion concentration variations. We use a new electrophysiological model that is both detailed and computationally efficient. This efficient model is based on the partial differential equation method. The central finite difference method is used for numerical solving of the two-dimensional (2D) wave propagation equation. Simulations are implemented in two stages, as a single cardiac cell and as a two-dimensional grid of cells. In both stages, the normal action potential formation in case of a single cell and it's normal propagation in case of a two-dimensional grid of cells were simulated with nominal sodium ion conductance. Then, the effect of sodium ion concentration on the action potential signal was studied by reducing the sodium ion conductance. It is concluded that reducing the sodium ion conductance, decreases both passing ability and conduction velocity of the action potential wave front.

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12

Mao, Ji Ze, Zhi Yuan Zhang, Zong Min Liu, and Chao Sun. "Damage Analysis of Concrete Subjected to Freeze-Thaw Cycles and Chloride Ion Erosion." Key Engineering Materials 488-489 (September 2011): 464–67. http://dx.doi.org/10.4028/www.scientific.net/kem.488-489.464.

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With the development of damage mechanics, many researchers have used it to analyze the constitutive equation of concrete. Since the special environment in the cold marine regions, the offshore structures are common to subject to the comprehensive effects of freeze-thaw action and chloride erosion. This might cause concrete materials degradation and reduce the mechanical performance of concrete seriously. In this paper, based on the analysis and mechanical experiments of concrete materials under the comprehensive effects of freeze-thaw action and chloride ion erosion, the damage evolution equation of concrete elastic modulus along with the freeze-thaw cycles and chloride ion contents was established. The effects of chloride ion were investigated during the process of concrete degradation. According to the damage evolution equation, a new constitutive equation of concrete under freeze-thaw action and chloride erosion was established. And then, by means of the element simulation analysis of concrete beams when subjected to the comprehensive actions, the feasibility and applicability of the equation was examined and discussed. In this equation, both the freeze-thaw action and chloride ion erosion were considered together. It will be more suitable for analyzing the durability of concrete structures in the real cold marine regions. It will also provide some references for concrete constitutive theory.

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13

Unwin, Nigel. "Neurotransmitter action: Opening of ligand-gated ion channels." Cell 72 (January 1993): 31–41. http://dx.doi.org/10.1016/s0092-8674(05)80026-1.

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14

Keynes, Richard. "Opening the gate Ion channels, molecules in action." Trends in Biochemical Sciences 22, no. 2 (February 1997): 70–71. http://dx.doi.org/10.1016/s0968-0004(97)84914-6.

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15

Allingham, John S., and David B. Haniford. "Mechanisms of Metal Ion Action in Tn10 Transposition." Journal of Molecular Biology 319, no. 1 (May 2002): 53–65. http://dx.doi.org/10.1016/s0022-2836(02)00297-8.

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16

Shajan, Anisha Brigit. "Action of Calcium Ion on Human Parathyroid Hormone." Journal of Bioinformatics and Intelligent Control 2, no. 4 (December 1, 2013): 298–99. http://dx.doi.org/10.1166/jbic.2013.1061.

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17

Wang, Jun. "Watching Microstructures in Action in Lithium-Ion Batteries." ChemElectroChem 1, no. 2 (January 21, 2014): 329–31. http://dx.doi.org/10.1002/celc.201300267.

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18

McCarthy, T. J., J. J. Zeelie, and D. J. Krause. "The antimicrobial action of zinc ion/antioxidant combinations." Journal of Clinical Pharmacy and Therapeutics 17, no. 1 (February 1992): 51–54. http://dx.doi.org/10.1111/j.1365-2710.1992.tb01265.x.

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19

WACHTEL, RUTH E., and EDWARD S. WEGRZYNOWICZ. "Mechanism of Volatile Anesthetic Action on Ion Channels." Annals of the New York Academy of Sciences 625, no. 1 Molecular and (June 1991): 116–28. http://dx.doi.org/10.1111/j.1749-6632.1991.tb33835.x.

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20

Garlid, K. D., M. Jaburek, and P. Jezek. "Mechanism of uncoupling protein action." Biochemical Society Transactions 29, no. 6 (November 1, 2001): 803–6. http://dx.doi.org/10.1042/bst0290803.

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Two competing models of uncoupling protein (UCP) transport mechanism agree that fatty acids (FAs) are obligatory for uncoupling, but they disagree about which ion is transported. In Klingenberg's model, UCPs conduct protons. In Garlid's model, UCPs conduct anions, like all members of this gene family. In the latter model, UCP transports the anionic FA head group from one side of the membrane to the other, and the cycle is completed by rapid flip-flop of protonated FAs across the bilayer. The head groups of the FA analogues, long-chain alkylsulphonates, are translocated by UCP, but they cannot induce uncoupling, because these strong acids cannot be protonated for the flip-flop part of the cycle. We have overcome this limitation by ion-pair transport of undecanesulphonate with propranolol, which causes the sulphonate to deliver protons across the membrane as if it were an FA. Full GDP-sensitive uncoupling is seen in the presence of propranolol and undecanesulphonate. This result confirms that the mechanism of UCP uncoupling requires transport of the anionic FA head group by UCP and that the proton transport occurs via the bilayer and not via UCP.

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21

Armstrong, Clay M., and Andrey Loboda. "A Model for 4-Aminopyridine Action on K Channels: Similarities to Tetraethylammonium Ion Action." Biophysical Journal 81, no. 2 (August 2001): 895–904. http://dx.doi.org/10.1016/s0006-3495(01)75749-9.

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22

DeGaspari, John. "HIP Action." Mechanical Engineering 126, no. 12 (December 1, 2004): 40–43. http://dx.doi.org/10.1115/1.2004-dec-4.

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The success of hip implants with elderly recipients has encouraged surgeons to increasingly perform hip replacement surgery on younger, more active patients as well. The condition that causes hip prostheses to loosen is known as osteolysis. While the problem affects only a relatively small set of recipients now, it may well grow as hip replacement surgery encompasses a wider range of eligible patients. A research group at the University of Leeds in the United Kingdom says it has patented a ceramic-on-metal hip prosthesis that produces one-tenth the wear particles of currently available hip replacement joints. The prosthesis has been licensed to a prosthetic manufacturer and is about to enter clinical trials in Europe. Some companies produce highly cross-linked polyethylene, either by thermal treatment or by radiation. Stryker Orthopaedics has Crossfire hip implants using highly cross-linked polyethylene cups against a metal ball. The company developed a ceramic-on-ceramic joint replacement, which it commercialized in 2003. The new Trident joint uses bearing surfaces of alumina ceramic. The company claims it has scratch resistance, low wear rates, good wettability for lubrication, and no ion release.

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23

Zhu, Jin Song, and Li Kun He. "Cellular Automata-Based Chloride Ion Diffusion Modelling of Concrete Bridge under Multifactor Coupling Action." Advanced Materials Research 368-373 (October 2011): 1407–10. http://dx.doi.org/10.4028/www.scientific.net/amr.368-373.1407.

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In order to accurately simulate the diffusion of chloride ion in the existing concrete bridge and acquire the precise concentration of chloride ion at any time, a Cellular Automata(CA)-based model is proposed. Firstly, the process of chloride ion diffusion is analyzed by the CA method and a nonlinear solution to the Fick’s second law is obtained. Secondly, considering the impact of various factors such as stress states, temporal and spatial variability of diffusion parameters and water-cement ratio on the process of chloride ion diffusion, the model of chloride ion diffusion under multifactor coupling is presented. Finally, a chloride ion penetrating experiment is used to prove the effectiveness and reasonability of this present method. A T-type beam is taken as an illustrative example to analyze the process of chloride ion diffusion.

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24

Dr. L.H. Pinto. "Viral ion channels as models for ion transport and targets for antiviral drug action." FEBS Letters 560, no. 1-3 (February 4, 2004): 1–2. http://dx.doi.org/10.1016/j.febslet.2004.01.052.

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25

Rudy, Yoram, and Jonathan R. Silva. "Computational biology in the study of cardiac ion channels and cell electrophysiology." Quarterly Reviews of Biophysics 39, no. 1 (February 2006): 57–116. http://dx.doi.org/10.1017/s0033583506004227.

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1. Prologue 582. The Hodgkin–Huxley formalism for computing the action potential 592.1 The axon action potential model 592.2 Cardiac action potential models 623. Ion-channel based formulation of the action potential 653.1 Ion-channel structure 653.2 Markov models of ion-channel kinetics 663.3 Role of selected ion channels in rate dependence of the cardiac action potential 713.4 Physiological implications of IKs subunit interaction 773.5 Mechanism of cardiac action potential rate-adaptation is species dependent 784. Simulating ion-channel mutations and their electrophysiological consequences 814.1 Mutations in SCN5A, the gene that encodes the cardiac sodium channel 824.1.1 The ΔKPQ mutation and LQT3 824.1.2 SCN5A mutation that underlies a dual phenotype 874.2 Mutations in HERG, the gene that encodes IKr: re-examination of the ‘gain of function/loss of function’ concept 944.3 Role of IKs as ‘repolarization reserve’ 1005. Modeling cell signaling in electrophysiology 1025.1 CaMKII regulation of the Ca2+ transient 1025.2 The β-adrenergic signaling cascade 1056. Epilogue 1077. Acknowledgments 1088. References 109The cardiac cell is a complex biological system where various processes interact to generate electrical excitation (the action potential, AP) and contraction. During AP generation, membrane ion channels interact nonlinearly with dynamically changing ionic concentrations and varying transmembrane voltage, and are subject to regulatory processes. In recent years, a large body of knowledge has accumulated on the molecular structure of cardiac ion channels, their function, and their modification by genetic mutations that are associated with cardiac arrhythmias and sudden death. However, ion channels are typically studied in isolation (in expression systems or isolated membrane patches), away from the physiological environment of the cell where they interact to generate the AP. A major challenge remains the integration of ion-channel properties into the functioning, complex and highly interactive cell system, with the objective to relate molecular-level processes and their modification by disease to whole-cell function and clinical phenotype. In this article we describe how computational biology can be used to achieve such integration. We explain how mathematical (Markov) models of ion-channel kinetics are incorporated into integrated models of cardiac cells to compute the AP. We provide examples of mathematical (computer) simulations of physiological and pathological phenomena, including AP adaptation to changes in heart rate, genetic mutations in SCN5A and HERG genes that are associated with fatal cardiac arrhythmias, and effects of the CaMKII regulatory pathway and β-adrenergic cascade on the cell electrophysiological function.

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26

Gonzalez-Raya, Tasio, Enrique Solano, and Mikel Sanz. "Quantized Three-Ion-Channel Neuron Model for Neural Action Potentials." Quantum 4 (January 20, 2020): 224. http://dx.doi.org/10.22331/q-2020-01-20-224.

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The Hodgkin-Huxley model describes the conduction of the nervous impulse through the axon, whose membrane's electric response can be described employing multiple connected electric circuits containing capacitors, voltage sources, and conductances. These conductances depend on previous depolarizing membrane voltages, which can be identified with a memory resistive element called memristor. Inspired by the recent quantization of the memristor, a simplified Hodgkin-Huxley model including a single ion channel has been studied in the quantum regime. Here, we study the quantization of the complete Hodgkin-Huxley model, accounting for all three ion channels, and introduce a quantum source, together with an output waveguide as the connection to a subsequent neuron. Our system consists of two memristors and one resistor, describing potassium, sodium, and chloride ion channel conductances, respectively, and a capacitor to account for the axon's membrane capacitance. We study the behavior of both ion channel conductivities and the circuit voltage, and we compare the results with those of the single channel, for a given quantum state of the source. It is remarkable that, in opposition to the single-channel model, we are able to reproduce the voltage spike in an adiabatic regime. Arguing that the circuit voltage is a quantum variable, we find a purely quantum-mechanical contribution in the system voltage's second moment. This work represents a complete study of the Hodgkin-Huxley model in the quantum regime, establishing a recipe for constructing quantum neuron networks with quantum state inputs. This paves the way for advances in hardware-based neuromorphic quantum computing, as well as quantum machine learning, which might be more efficient resource-wise.

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27

Martí, Albert, Juan J. Pérez, and Jordi Madrenas. "Action potential propagation: ion current or intramembrane electric field?" General physiology and biophysics 37, no. 01 (2018): 71–82. http://dx.doi.org/10.4149/gpb_2017017.

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28

Carmeliet, Edward, and Kanigula Mubagwa. "Antiarrhythmic drugs and cardiac ion channels: mechanisms of action." Progress in Biophysics and Molecular Biology 70, no. 1 (July 1998): 1–72. http://dx.doi.org/10.1016/s0079-6107(98)00002-9.

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29

Franks, N. P. "Ion channels and inhalational anaesthetics: molecular mechanisms of action." European Journal of Anaesthesiology 17, Supplement 20 (2000): 12–13. http://dx.doi.org/10.1097/00003643-200000003-00025.

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30

Kajdas, C., and K. Hiratsuka. "Tribochemistry, tribocatalysis, and the negative-ion-radical action mechanism." Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology 223, no. 6 (March 18, 2009): 827–48. http://dx.doi.org/10.1243/13506501jet514.

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31

SEVERAL AUTHORS, SEVERAL AUTHORS. "ChemInform Abstract: Molecular Action of Insecticides on Ion Channels." ChemInform 26, no. 45 (August 17, 2010): no. http://dx.doi.org/10.1002/chin.199545315.

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32

Han, Yejee, Youngmin You, Yong-Min Lee, and Wonwoo Nam. "Double Action: Toward Phosphorescence Ratiometric Sensing of Chromium Ion." Advanced Materials 24, no. 20 (April 20, 2012): 2748–54. http://dx.doi.org/10.1002/adma.201104467.

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33

El-Mallakh, Rif S. "Ion homeostasis and the mechanism of action of lithium." Clinical Neuroscience Research 4, no. 3-4 (December 2004): 227–31. http://dx.doi.org/10.1016/j.cnr.2004.09.014.

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34

Mann, Stefan A., Adam Hill, and Jamie I. Vandenberg. "Investigating Ion Channel Diseases With Dynamic Action Potential Clamp." Biophysical Journal 96, no. 3 (February 2009): 259a. http://dx.doi.org/10.1016/j.bpj.2008.12.1279.

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35

Zhao, Q. L., and Y. Z. Zhang. "Concentration Distribution of Chloride Ion under the Influence of the Convection-Diffusion Coupling." Advances in Materials Science and Engineering 2017 (2017): 1–10. http://dx.doi.org/10.1155/2017/2076986.

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The transfer process of chloride ion under the action of the convection-diffusion coupling was analyzed in order to predict the corrosion of reinforcement and the durability of structure more accurately. Considering the time-varying properties of diffusion coefficient and the space-time effect of the convection velocity, the differential equation for chloride ion transfer under the action of the convection-diffusion coupling was constructed. And then the chloride ion transfer model was validated by the existing experimental datum and the actual project datum. The results showed that when only diffusion was considered, the chlorine ion concentration increased with the time and decreased with the decay index of time. Under the action of the convection-diffusion coupling, at each point of coupling region, the chloride ion concentration first increased and then decreased and tended to stabilize, and the maximum appeared at the moment of convection velocity being 0; in the diffusion zone, the chloride ion concentration increased over time, and the chloride ion concentration of the same location increased with the depth of convection (in the later period), the velocity of convection (in the early period), and the chloride ion concentration of the surface.

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36

Wang, Xiaojun, Yulong Zhuo, Shuqiang Deng, Yongxin Li, Wen Zhong, and Kui Zhao. "Experimental Research on the Impact of Ion Exchange and Infiltration on the Microstructure of Rare Earth Orebody." Advances in Materials Science and Engineering 2017 (2017): 1–8. http://dx.doi.org/10.1155/2017/4762858.

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To detect the evolutional characteristics of pore structure in ore leaching process of ion-type rare earth, this paper analyzes the influence mechanism of ion exchange seepage action on the microstructure of orebody, and an experiment for remodeling rare earth saturated samples and ore leaching was designed. Using nuclear magnetic resonance technology obtains the pore structure T2 map of H2O and (NH4)2SO4 solution in the ore leaching process and inverts and reconstitutes the pore structure distribution image. The results of contrastive analysis experiments indicate that impact factors of the ore leaching process on the microstructure of rare earth orebodies include two aspects: solution seepage and ion exchange. The main factor of pore structure distribution is the ion exchange action, determined by a dual effect. The sole action of solution seepage leads to an increase in pore size, which means that pore size structure is changing from small and medium to macro. Ion exchange gives rise to the movement and restructuring of particles, which results in a decrease in pore sizes. The pore structure changes from loose to compact; in the entire ore leaching process, the ion exchange action advances in a layered shape along the direction of seepage, and the chemical replacement and physical seepage alternately impact the microstructure of the orebodies.

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37

Roux, Benoît. "Ion channels and ion selectivity." Essays in Biochemistry 61, no. 2 (May 9, 2017): 201–9. http://dx.doi.org/10.1042/ebc20160074.

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Specific macromolecular transport systems, ion channels and pumps, provide the pathways to facilitate and control the passage of ions across the lipid membrane. Ion channels provide energetically favourable passage for ions to diffuse rapidly and passively according to their electrochemical potential. Selective ion channels are essential for the excitability of biological membranes: the action potential is a transient phenomenon that reflects the rapid opening and closing of voltage-dependent Na+-selective and K+-selective channels. One of the most critical functional aspects of K+ channels is their ability to remain highly selective for K+ over Na+ while allowing high-throughput ion conduction at a rate close to the diffusion limit. Permeation through the K+ channel selectivity filter is believed to proceed as a ‘knockon’ mechanism, in which 2–3 K+ ions interspersed by water molecules move in a single file. Permeation through the comparatively wider and less selective Na+ channels also proceeds via a loosely coupled knockon mechanism, although the ions do not need to be fully dehydrated. While simple structural concepts are often invoked to rationalize the mechanism of ion selectivity, a deeper analysis shows that subtle effects play an important role in these flexible dynamical structures.

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38

Korman, Can E., and Isaak D. Mayergoyz. "On hysteresis of ion channels." Mathematical Modelling of Natural Phenomena 15 (2020): 26. http://dx.doi.org/10.1051/mmnp/2019058.

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Ion channel proteins have many conformational (metastable) states and, for this reason, they exhibit hysteresis. This fact is responsible for the non-Markovian stochastic nature of single ion channel recordings. It is suggested in the paper that the stochastic single channel recordings can be modeled as the random outputs of rectangular hysteresis loops driven by stochastic processes. The latter problem can be mathematically treated as an exit problem for stochastic processes or by using the theory of stochastic processes on graphs. It is also demonstrated in the paper that the collective action of sodium and potassium channels responsible for the generation and propagation of action potentials exhibit hysteresis. This demonstration is accomplished by using the inverse problem approach to the nonlinear Hodgkin-Huxley diffusion equation.

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Bowman, W. C. "Second messenger systems as sites of drug action." Proceedings of the Royal Society of Edinburgh. Section B. Biological Sciences 99, no. 1-2 (1992): 1–17. http://dx.doi.org/10.1017/s0269727000013002.

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Synopsis:Transmembrane signalling from cell surface receptors occurs by two broad mechanisms: (i) the rapid (ms) direct opening of an ion channel, where the ion channel is a component of the receptor complex (e.g. the nicotinic acetylcholine receptor); and (ii) the more slow (s) modulation of a membrane enzyme or more distant ion channel. Most of the examples of this second mechanism involve a GTP-binding protein or so–called G-protein, and the production of a second messenger. The production of nitric oxide is a special case in that it is eventually produced as a result of the activity of the second messenger ïnositol trisphosphate. The nitric oxide then diffuses into a second cell to give rise to the production of an additional ‘second’ messenger, cyclic GMP.All of the surface receptors themselves exist as a number of subtypes. Additionally, most of the components of the second messenger systems – G-proteins, adenylyl cyclase, guanylyl cyclase, phosphoinositidase, C, inositol trisphosphate receptors, protein kinase A, protein kinase G, protein kinase C, cyclic nucleotide phosphodiesterases, and the enzymes involved in phosphatidylinositol resynthesis – occur in a number of isoforms. Furthermore, all the enzymes are controlled in their activity by a number of co-factors and other modulators. This diversity provides the potential for selective drug action, a potential which is already being exploited and which will be increasingly so in the near future.

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40

Szabó, Adrienn, Norbert Szentandrássy, Péter Birinyi, Balázs Horváth, Gergely Szabó, Tamás Bányász, Ildikó Márton, János Magyar, and Péter P. Nánási. "Effects of Ropivacaine on Action Potential Configuration and Ion Currents in Isolated Canine Ventricular Cardiomyocytes." Anesthesiology 108, no. 4 (April 1, 2008): 693–702. http://dx.doi.org/10.1097/aln.0b013e3181684b91.

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Background Despite the widespread clinical application of ropivacaine, there is little information on the cellular cardiac effects of the drug. In the current study, therefore, the concentration-dependent effects of ropivacaine on action potential morphology and the underlying ion currents were studied and compared with those of bupivacaine in isolated canine ventricular cardiomyocytes. Methods Action potentials were recorded from the enzymatically dispersed cells using sharp microelectrodes. Conventional patch clamp and action potential voltage clamp arrangements were used to study the effects of ropivacaine on transmembrane ion currents. Results Ropivacaine induced concentration- and frequency-dependent changes in action potential configuration, including shortening of the action potentials, reduction of their amplitude and maximum velocity of depolarization, suppression of early repolarization, and depression of plateau. Reduction in maximum velocity of depolarization was characterized with an EC50 value of 81 +/- 7 microm at 1 Hz. Qualitatively similar results were obtained with bupivacaine (EC50 = 47 +/- 3 microm). Under voltage clamp conditions, a variety of ion currents were blocked by ropivacaine: L-type calcium current (EC50 = 263 +/- 67 microm), transient outward current (EC50 = 384 +/- 75 microm), inward rectifier potassium current (EC50 = 372 +/- 35 microm), rapid delayed rectifier potassium current (EC50 = 303 +/- 47 microm), and slow delayed rectifier potassium current (EC50 = 106 +/- 18 microm). Conclusions Ropivacaine, similarly to bupivacaine, can modify cardiac action potentials and the underlying ion currents at concentrations higher than the usual therapeutic range. However, in cases of overdose, cardiac complications may be anticipated both during and after anesthesia due to the blockade of various ion currents.

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41

Wang, Cai Hui, Jin Yang Jiang, Guo Wen Sun, Jian De Han, and Yun Feng Qiao. "The Research of the Effect of Dynamic Load and Temperature on the Diffusion Performance of Chlorideion in Concrete." Advanced Materials Research 163-167 (December 2010): 3167–73. http://dx.doi.org/10.4028/www.scientific.net/amr.163-167.3167.

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The diffusion performance of chloride ion in concrete under the coupling action of dynamic load and environment was researched by a new set of experimental system. The experiment are composed of study of saturated performance of concrete, diffusion performance of chloride ion with different water binder ratio and under coupling action of dynamic load and temperature. The results show that the transport mechanism of chloride ion in concrete accounted with diffusion theory due to the 99% of saturation degree of concrete; the diffusion coefficient of chloride ion is decreased with the increasing water binder ratio, but is increased with temperature increase; and the diffusion coefficient of chloride ion is changed with cycle number.

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42

Huang, Wei Bo, Xu Dong Liu, Ping Lu, and Jing Zhang. "Evaluation of the Properties of Polyaspartic Polyurea Coated Concrete Subjected to the Co-Action of Freeze-Thaw Cycles and NaCl Solution Immersion." Materials Science Forum 689 (June 2011): 336–42. http://dx.doi.org/10.4028/www.scientific.net/msf.689.336.

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The deterioration of coated concrete subjected to co-action of freeze-thaw cycles-NaCl solution immersion double factors exposure was investigated in this study. Adhesion, chloride content and resistance of chloride ion diffusivity of two types of polyaspartic ester polyurea coated concrete were analyzed. Test results showed that the adhesion of QF-1 (PAE-b-H12MDI prepolymer H66) and QF-2 (PAE-b-H12MDI prepolymer H62) coated concrete reduced about 5% respectively which kept excellent under the double factors exposure after 200, 300 days and 25, 50 times of cycles. The degradation process of coated concrete simultaneously exposed to co-action exposure was significantly accelerated. In co-action exposure tests, the average chloride ion content of coated concrete increased about 33% and 87% after 25 and 50 times of cycles compared with single NaCl solution immersion exposure; the chloride ion diffusion coefficient of concrete substrate increased with the increase of exposure time and freeze-thaw cycles. Freeze-thaw cycles results showed a severe influence on chloride ion diffusion and permeation of surface protection coating of concrete. Research also showed that the chloride ion diffusion of coated concrete subjected to the co-action of freeze-thaw cycles-NaCl solution was coincided with the Fick’s second law.

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KUMAMOTO, Eiichi. "Action of lanthanoide ion on amino-acid receptor-channel-Is this ion species specifically recognized?" Seibutsu Butsuri 38, no. 3 (1998): 99–103. http://dx.doi.org/10.2142/biophys.38.99.

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Sah, Maheshwar Pd, Hyongsuk Kim, Abdullah Eroglu, and Leon Chua. "Memristive Model of the Barnacle Giant Muscle Fibers." International Journal of Bifurcation and Chaos 26, no. 01 (January 2016): 1630001. http://dx.doi.org/10.1142/s0218127416300019.

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The generation of action potentials (oscillations) in biological systems is a complex, yet poorly understood nonlinear dynamical phenomenon involving ions. This paper reveals that the time-varying calcium ion and the time-varying potassium ion, which are essential for generating action potentials in Barnacle giant muscle fibers are in fact generic memristors in the perspective of electrical circuit theory. We will show that these two ions exhibit all the fingerprints of memristors from the equations of the Morris–Lecar model of the Barnacle giant muscle fibers. This paper also gives a textbook reference to understand the difference between memristor and nonlinear resistor via analysis of the potassium ion-channel memristor and calcium ion-channel nonlinear resistor. We will also present a comprehensive in-depth analysis of the generation of action potentials (oscillations) in memristive Morris–Lecar model using small-signal circuit model and the Hopf bifurcation theorem.

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Coates, Leighton. "Ion permeation in potassium ion channels." Acta Crystallographica Section D Structural Biology 76, no. 4 (April 1, 2020): 326–31. http://dx.doi.org/10.1107/s2059798320003599.

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The study of ion channels dates back to the 1950s and the groundbreaking electrophysiology work of Hodgin and Huxley, who used giant squid axons to probe how action potentials in neurons were initiated and propagated. More recently, several experiments using different structural biology techniques and approaches have been conducted to try to understand how potassium ions permeate through the selectivity filter of potassium ion channels. Two mechanisms of permeation have been proposed, and each of the two mechanisms is supported by different experiments. The key structural biology experiments conducted so far to try to understand how ion permeation takes place in potassium ion channels are reviewed and discussed. Protein crystallography has made, and continues to make, key contributions in this field, often through the use of anomalous scattering. Other structural biology techniques used to study the contents of the selectivity filter include solid-state nuclear magnetic resonance and two-dimensional infrared spectroscopy, both of which make clever use of isotopic labeling techniques, while molecular-dynamics simulations of ion flow through the selectivity filter have been enabled by the growing number of potassium ion channel structures deposited in the Protein Data Bank.

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Glosík, Juraj, P. Hlavenka, R. Plašil, F. Windisch, D. Gerlich, A. Wolf, and H. Kreckel. "Action spectroscopy of and D 2 H + using overtone excitation." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 364, no. 1848 (September 20, 2006): 2931–42. http://dx.doi.org/10.1098/rsta.2006.1866.

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The ion and its deuterated isotopologues H 2 D + , D 2 H + and play an important role in astrophysical and laboratory plasmas. The main challenge for understanding these ions and their interaction at low temperatures are state-specific experiments. This requires manipulation and a simple but efficient in situ characterization of their low-lying rotational states. In this contribution we report measurements of near infrared (NIR) absorption spectra. Required high sensitivity is achieved by combining liquid nitrogen cooled plasma with the technique of NIR cavity ringdown absorption spectroscopy. The measured transition frequencies are then used for exciting cold ions stored in a low-temperature 22-pole radiofrequency ion trap. Absorption of a photon by the stored ion is detected by using the laser-induced reactions technique. As a monitor reaction, the endothermic proton (or deuteron) transfer to Ar is used in our studies. Since the formed ArH + (or ArD + ) ions are detected with near unit efficiency, the stored ions can be characterized very efficiently, even if there are just a few of them.

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Ihara, Makoto. "Mechanisms of action of insecticides on ligand-gated ion channels." Journal of Pesticide Science 32, no. 3 (2007): 278–80. http://dx.doi.org/10.1584/jpestics.32.278.

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Guo, Yi, Yan jun Zhang, Tang ping Xu, Chun xu Zhang, Jin sheng Chen, and Ping Jiang. "Study of Interrelationship Beteen Meridian Action and Calcium Ion concentration." Japanese Journal of Ryodoraku Medicine 39, no. 6 (1994): 204–6. http://dx.doi.org/10.17119/ryodoraku1986.39.204.

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HAMADA, Nobuyuki. "Recent Insights into the Biological Action of Heavy-Ion Radiation." Journal of Radiation Research 50, no. 1 (2009): 1–9. http://dx.doi.org/10.1269/jrr.08070.

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Housley, David M., Gary D. Housley, Michael J. Liddell, and Ernest A. Jennings. "Scorpion toxin peptide action at the ion channel subunit level." Neuropharmacology 127 (December 2017): 46–78. http://dx.doi.org/10.1016/j.neuropharm.2016.10.004.

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Journal articles on the topic 'Ion action'

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