Electrostatic precipitation pressurized intraperitoneal aerosol chemotherapy (ePIPAC): Finding the optimal electrical potential

The method of first integrals (MFI) based on the equation of motion for the displacement vector, or based on the one for the traction vector was introduced recently in order to find explicit secular equations of Rayleigh waves whose characteristic equations (i.e the equations determining the attenuation factor) are fully quartic or are of higher order (then the classical approach is not applicable). In this paper it is shown that, not only to Rayleigh waves, the MFI can be applicable also to other waves by running it on the equations for mixed vectors. In particular: (i) By applying the MFI to the equations for the displacement-traction vector we get the explicit dispersion equations of Stoneley waves in twinned crystals (ii) Running the MFI on the equations for the traction-electric induction vector and the traction-electrical potential vector provides the explicit dispersion equations of SH-waves in piezoelastic materials. The obtained dispersion equations are identical with the ones previously derived using the method of polarization vector, but the procedure of driving them is more simple.

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Functional Gradient Transparent Conducting Oxide Nanowire Arrays as Monophasic Schottky-Barrier Free Memristors for Bipolar Linear Switching

10.26434/chemrxiv.11866062.v1 ◽

2020 ◽

Author(s):

Thomas Herzog ◽

Naomi Weitzel ◽

Sebastian Polarz

Keyword(s):

Schottky Barrier ◽

Data Storage ◽

Tin Oxide ◽

Transparent Conducting Oxide ◽

Electrical Potential ◽

High Resistance State ◽

Nanowire Arrays ◽

Metal Metal ◽

Resistance State ◽

Barrier Free

<div><div><div><p>One of the fascinating properties of metal-semiconductor Schottky-barriers, which has been observed for some material combinations, is memristive behavior. Memristors are smart, since they can reversibly switch between a low resistance state and a high resistance state. The devices offer a great potential for advanced computing and data storage, including neuromorphic networks and resistive random-access memory. However, as for many other cases, the presence of a real interface (metal - metal oxide) has numerous disadvantages. The realization of interface-free, respectively Schottky-barrier free memristors is highly desirable. The aim of the current paper is the generation of nanowire arrays with each nanorod possessing the same crystal phase (Rutile) and segments only differing in composition. The electric conductivity is realized by segments made of highly-doped antimony tin oxide (ATO) transitioning into pure tin oxide (TO). Complex nanoarchitectures are presented, which include ATO-TO, ATO-TO-ATO nanowires either with a stepwise distribution of antimony or as a graded functional material. The electrical characterization of the materials reveals that the introduction of memristive properties in such structures is possible. The special features observed in voltage-current (IV) curves are correlated to the behavior of mobile oxygen vacancies (VO..) at different values of applied electrical potential.</p></div></div></div>

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Electrical Potential Distributions in a Heterogeneous Subsurface in Response to Applied Current

Vadose Zone Journal ◽

10.2136/vzj2002.0273 ◽

2002 ◽

Vol 1 (2) ◽

pp. 273

Author(s):

Alex Furman ◽

A. W. Warrick ◽

Ty P. A. Ferré

Keyword(s):

Electrical Potential ◽

Applied Current

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INTERPRETATION OF DISACCHARIDE-DEPENDENT ELECTRICAL POTENTIAL DIFFERENCES IN THE SMALL INTESTINE

The Japanese Journal of Physiology ◽

10.2170/jjphysiol.26.79 ◽

1976 ◽

Vol 26 (1) ◽

pp. 79-92 ◽

Cited By ~ 3

Author(s):

Yutaka IGARASHI ◽

Yoshitaka SAITO ◽

Masayoshi HIMUKAI ◽

Takeshi HOSHI

Keyword(s):

Small Intestine ◽

Electrical Potential

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NUMERICAL COMPUTATION OF CANARDS

International Journal of Bifurcation and Chaos ◽

10.1142/s0218127400001742 ◽

2000 ◽

Vol 10 (12) ◽

pp. 2669-2687 ◽

Cited By ~ 57

Author(s):

JOHN GUCKENHEIMER ◽

KATHLEEN HOFFMAN ◽

WARREN WECKESSER

Keyword(s):

Differential Equations ◽

Ordinary Differential Equations ◽

Electrical Potential ◽

Slow Manifold ◽

Singularly Perturbed ◽

Singularly Perturbed Systems ◽

Singularly Perturbed System ◽

Chemical Systems ◽

Perturbed System ◽

Physical And Chemical

Singularly perturbed systems of ordinary differential equations arise in many biological, physical and chemical systems. We present an example of a singularly perturbed system of ordinary differential equations that arises as a model of the electrical potential across the cell membrane of a neuron. We describe two periodic solutions of this example that were numerically computed using continuation of solutions of boundary value problems. One of these periodic orbits contains canards, trajectory segments that follow unstable portions of a slow manifold. We identify several mechanisms that lead to the formation of these and other canards in this example.

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OSMOTIC INHIBITION OF THE NATRIFERIC RESPONSE OF THE TOAD URINARY BLADDER TO VASOPRESSIN

Journal of Endocrinology ◽

10.1677/joe.0.0670119 ◽

1975 ◽

Vol 67 (1) ◽

pp. 119-125

Author(s):

P. J. BENTLEY

Keyword(s):

Urinary Bladder ◽

Water Movement ◽

Short Circuit ◽

Electrical Potential ◽

Short Circuit Current ◽

Toad Bladder ◽

Toad Urinary Bladder ◽

Electrical Potential Difference ◽

Osmotic Gradient

SUMMARY The electrical potential difference and short-circuit current (scc, reflecting active transmural sodium transport) across the toad urinary bladder in vitro was unaffected by the presence of hypo-osmotic solutions bathing the mucosal (urinary) surface, providing that the transmural flow of water was small. Vasopressin increased the scc across the toad bladder (the natriferic response), but this stimulation was considerably reduced in the presence of a hypo-osmotic solution on the mucosal side, conditions under which water transfer across the membrane was also increased. This inhibition of the natriferic response did not depend on the direction of the water movement, for if the osmotic gradient was the opposite way to that which normally occurs, the response to vasopressin was still reduced. The natriferic response to cyclic AMP was also inhibited in the presence of an osmotic gradient. Aldosterone increased the scc and Na+ transport across the toad bladder but this response was not changed when an osmotic gradient was present. The physiological implications of these observations and the possible mechanisms involved are discussed.

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The strain-generated electrical potential in cartilaginous tissues: a role for piezoelectricity

Biophysical Reviews ◽

10.1007/s12551-021-00779-9 ◽

2021 ◽

Vol 13 (1) ◽

pp. 91-100

Author(s):

Philip Poillot ◽

Christine L. Le Maitre ◽

Jacques M. Huyghe

Keyword(s):

Physiological Response ◽

Numerical Models ◽

Measurement Techniques ◽

Electrical Potential ◽

Evidence Base ◽

Piezoelectric Response ◽

Mechanical Forces ◽

Streaming Potentials ◽

Cartilaginous Tissues ◽

Electrical Potentials

AbstractThe strain-generated potential (SGP) is a well-established mechanism in cartilaginous tissues whereby mechanical forces generate electrical potentials. In articular cartilage (AC) and the intervertebral disc (IVD), studies on the SGP have focused on fluid- and ionic-driven effects, namely Donnan, diffusion and streaming potentials. However, recent evidence has indicated a direct coupling between strain and electrical potential. Piezoelectricity is one such mechanism whereby deformation of most biological structures, like collagen, can directly generate an electrical potential. In this review, the SGP in AC and the IVD will be revisited in light of piezoelectricity and mechanotransduction. While the evidence base for physiologically significant piezoelectric responses in tissue is lacking, difficulties in quantifying the physiological response and imperfect measurement techniques may have underestimated the property. Hindering our understanding of the SGP further, numerical models to-date have negated ferroelectric effects in the SGP and have utilised classic Donnan theory that, as evidence argues, may be oversimplified. Moreover, changes in the SGP with degeneration due to an altered extracellular matrix (ECM) indicate that the significance of ionic-driven mechanisms may diminish relative to the piezoelectric response. The SGP, and these mechanisms behind it, are finally discussed in relation to the cell response.

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Measuring implanted patient response to tone pips

BioMedical Engineering OnLine ◽

10.1186/s12938-020-00844-6 ◽

2021 ◽

Vol 20 (1) ◽

Author(s):

Juan M. Cornejo ◽

Agar K. Quintana ◽

Nohra E. Beltran ◽

Pilar Granados

Keyword(s):

Auditory Nerve ◽

Dynamic Range ◽

Test Procedure ◽

Electrical Potential ◽

Electrical Current ◽

Intensity Level ◽

Electromyographic Activity ◽

Variable Intensity ◽

Electrode Current ◽

Auditory Behavior

Abstract Background An electrical potential not previously reported—electrical cochlear response (ECR)—observed only in implanted patients is described. Its amplitude and growth slope are a measurement of the stimulation achieved by a tone pip on the auditory nerve. The stimulation and recording system constructed for this purpose, the features of this potential obtained in a group of 43 children, and its possible clinical use are described. The ECR is obtained by averaging the EEG epochs acquired each time the cochlear implant (CI) processes a tone pip of known frequency and intensity when the patient is sleeping and using the CI in everyday mode. The ECR is sensitive to tone pip intensity level, microphone sensitivity, sound processor gain, dynamic range of electrical current, and responsiveness to electrical current of the auditory nerve portion involved with the electrode under test. It allows individual evaluation of intracochlear electrodes by choosing, one at the time, the central frequency of the electrode as the test tone pip frequency, so the ECR measurement due to a variable intensity tone pip allows to establish the suitability of the dynamic range of the electrode current. Results There is a difference in ECR measurements when patients are grouped based on their auditory behavior. The ECR slope and amplitude for the Sensitive group is 0.2 μV/dBHL and 10 μV at 50 dBHL compared with 0.04 μV/dBHL and 3 μV at 50dBHL for the Inconsistent group. The clinical cases show that adjusting the dynamic range of current based on the ECR improved the patient’s auditory behavior. Conclusions ECR can be recorded regardless of the artifact due to the electromyographic activity of the patient and the functioning of the CI. Its amplitude and growth slope versus the intensity of the stimulus differs between electrodes. The relationship between minimum ECR detection intensity level and auditory threshold suggests the possibility of estimating patient auditory thresholds this way. ECR does not depend on the subject’s age, cooperation, or health status. It can be obtained at any time after implant surgery and the test procedure is the same regardless of device manufacturer.

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Electrodiffusion Phenomena in Neuroscience and the Nernst–Planck–Poisson Equations

Electrochem ◽

10.3390/electrochem2020014 ◽

2021 ◽

Vol 2 (2) ◽

pp. 197-215

Author(s):

Jerzy J. Jasielec

Keyword(s):

Electrical Potential ◽

Signal Propagation ◽

Liquid Junction Potential ◽

Liquid Junction ◽

Patch Clamp Technique ◽

Poisson Equations ◽

Cellular Environment ◽

Electrochemical Transport ◽

Insight Into ◽

Junction Potential

This work is aimed to give an electrochemical insight into the ionic transport phenomena in the cellular environment of organized brain tissue. The Nernst–Planck–Poisson (NPP) model is presented, and its applications in the description of electrodiffusion phenomena relevant in nanoscale neurophysiology are reviewed. These phenomena include: the signal propagation in neurons, the liquid junction potential in extracellular space, electrochemical transport in ion channels, the electrical potential distortions invisible to patch-clamp technique, and calcium transport through mitochondrial membrane. The limitations, as well as the extensions of the NPP model that allow us to overcome these limitations, are also discussed.

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