Marius Barlea

Technical University of Cluj-Napoca, Physics Department, Faculty Member

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Papers by Marius Barlea

How to Describe the Skin’s Electrical Nonlinear Response

International Conference on Advancements of Medicine and Health Care through Technology; 12th - 15th October 2016, Cluj-Napoca, Romania, 2017

The skin’s electrical nonlinearities found experimentally arerelated to stratum corneum and model... more The skin’s electrical nonlinearities found experimentally arerelated to stratum corneum and modeled by the parallel resistance (Rp) as a linear current dependence in conductance (1/Rp). We show that such dependence could occur because the skin’s current-voltage characteristic has a non-ohmic linear portion at large voltage, due to pores’ conduction, that can be detected as a constant dynamic resistance (dU/dI).

Aplication of Blade Electrodes in Electroporation and his Importance in Electrical Properties of Skin

2019 11th International Symposium on Advanced Topics in Electrical Engineering (ATEE), 2019

For electroporation and bioimpedance measurements applications it is important to obtain informat... more For electroporation and bioimpedance measurements applications it is important to obtain information about the electrical distribution considering the different types of electrodes. This article will work strictly on blades of stainless steel electrodes. The simulations are realized in the Comsol program which uses different patterns of elements in methodical of electrical distribution of electrical field and electrical curents. In this paper, simulations and measurements will be performed to determine the applicability of blade electrodes for electrical model of the skin and electroporation. The results provide an overview of the distribution of electricity both in liquid medium and the solid medium for electroporation. To check the applicability of these electrodes, a customary electrical model of the skin will be used.

Determination of the Electrical Parameters of Some ECG Electrodes

In this paper we verify if ECG electrodes are adequate for the bioimpedance measurement. A square... more In this paper we verify if ECG electrodes are adequate for the bioimpedance measurement. A square wave signal (U=1V, f=5, 500, 5000 Hz) is applied to a calibrated resistance R=10 kΩ, in series with two identical ECG electrodes glued together by their adhesive part. Using an appropiate model, we find from the data a series resistance with one or more groups of a parallel resistance Ri with a capacitor Ci (i=1, 2, 3).

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Electrical methods for testing building and construction materials

Electrical methods for the assessment of materials are gaining interest because of their ease of ... more Electrical methods for the assessment of materials are gaining interest because of their ease of implementation. This paper presents some electrical techniques for cement and concrete characterization. For example, electrical resistivity of cement is correlated with its compressive strength and can be used to monitor the real-time evolution of cracking concrete. Archie's laws, which link the electrical conductivity to the material's porosity and to the structure of this porosity (tortuosity) can, estimate the ideal mix of concrete for a specific service life and environmental class. Electrical conductivity measurements can predict the fluid permeability through a porous material (Katz-Thompson formula) and this leads to a better design of pervious concretes for the maximization of water transport. Electrical measurements offer relevant information and versatility, and this makes them ideal for quality control, for designing and assessing construction and building materials.

Water as a Third Compartment within the Skin’s Stratum Corneum

IFMBE Proceedings, 2014

ABSTRACT In this position paper we present our view of how water is distributed inside the skin&a... more ABSTRACT In this position paper we present our view of how water is distributed inside the skin&#39;s stratum corneum to create its electrical properties. The existence of a finite electrical resistance of the skin, especially for direct current, implies a continuous domain of water from the surface of the skin to the inner of the body. We propose water as a third compartment in stratum corneum that interpenetrates the other two compartments: intercellular lipids and corneocytes. We suppose that water exchange between the two generally accepted compartments, intercellular lipids and corneocytes, takes place at the junction between corneodesmosomes and lamellar extracellular lipids. We present the evidences from scientific literature sustaining such a view for water distribution in stratum corneum. This assumption could explain some electrical properties of the skin and why skin&#39;s permeability to hydrophilic solutes is better predicted by models that imply a substance transport through corneocytes and lipid bilayers in series.

Model of the Current-Voltage Relation for a Skin Pore

IFMBE Proceedings, 2011

ABSTRACT Using a Nernst-Planck model, we show that the current density in a membrane&#39;s po... more ABSTRACT Using a Nernst-Planck model, we show that the current density in a membrane&#39;s pore as a function of voltage has three types of behavior: a quasi-ohmic behavior at low voltages, with a small slope, a non-ohmic linear dependence at large voltages, with a large slope, and a nonlinear transition region at intermediate voltages. The magnitude of the quasi-ohmic current from low voltages depends mainly on the height of energy barrier inside the pore, w, through an exponential term, ew. The low voltages domain is experimentally accessible and almost unexplored, despite the fact that it can offer direct information about the energy barrier inside a pore. The model has only two assumed parameters, the energy barrier height, w, and the relative size of the entrance region of the pore, r, with a clear physical meaning, an important advantage for fitting and interpreting experimental data. This simple model for the current-voltage nonlinearity is a good starting point for explaining the electrical behavior of the skin at low voltages. IFMBE Proceedings, 2011, Volume 36, Part 2, 156-159, DOI: 10.1007/978-3-642-22586-4_33 http://www.springerlink.com/content/q6332305485k48u2/

The Skin’s Electrical Time Constants

IFMBE Proceedings, 2011

ABSTRACT We have studied the electrical time constants of human skin potential in response to a c... more ABSTRACT We have studied the electrical time constants of human skin potential in response to a constant current impulse (0.4-16 mA/100 us). Three relaxation times were found with values in the range 10-40 us, 100-200 us and 1-4 ms. By correlating the time constants with the electrical model of the skin we found that stratum corneum has a nonlinear resistance that diminishes and a nonlinear capacitance that increases with increasing values of current. IFMBE Proceedings, 2011, Volume 36, Part 2, 160-163, DOI: 10.1007/978-3-642-22586-4_34 http://www.springerlink.com/content/w7573u5j7513j332/

Shaping traffic flow with a ratio of time constants

Central European Journal of Engineering, 2014

In this paper we present how the main parameters of an optimal velocity model, the velocity adapt... more In this paper we present how the main parameters of an optimal velocity model, the velocity adaptation time, τ, and the desired time gap between consecutive vehicles (time headway), T, control the structure of vehicular traffic flow. We show that the ratio between the desired time gap and the velocity adaptation time, T /τ, establishes the pattern formation in congested traffic flow. This ratio controls both the collective behavior and the individual response of vehicles in traffic. We also introduced a response (transfer) function, which shows how perturbation is transmitted between adjacent vehicles and permits the study of collective stability of traffic flow.

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The current-voltage relation of a pore and its asymptotic behavior in a Nernst-Planck model

Journal of Electrical Bioimpedance, 2012

A model for current-voltage nonlinearity and asymmetry is a good starting point for explaining th... more A model for current-voltage nonlinearity and asymmetry is a good starting point for explaining the electrical behavior of nanopores in synthetic or biological membranes. Using a Nernst-Planck model, we found three behaviors for the calculated current density in a membrane's pore as a function of voltage: a quasi-ohmic, slow rising linear current at low voltages; a nonlinear current at intermediate voltages; and a non-ohmic, fast rising linear current at large voltages. The slope of the quasi-ohmic current depends mainly on the height of the energy barrier inside the pore, w, through an exponential term, ew. The magnitude of the non-ohmic linear current is controlled by the potential energy gradient at the pore entrance, w/r. The current-voltage relationship is asymmetric if the ion's potential energy inside the pore has an asymmetric triangular profile. The model has only two assumed parameters, the energy barrier height, w, and the relative size of the entrance region of th...

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Changes in the electrical properties of the electrode–skin–underlying tissue composite during a week-long programme of neuromuscular electrical stimulation

Physiological Measurement, 2014

Particular neuromuscular electrical stimulation (NMES) applications require the use of the same e... more Particular neuromuscular electrical stimulation (NMES) applications require the use of the same electrodes over a long duration (&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;1 day) without having access to them. Under such circumstance the quality of the electrode-skin contact cannot be assessed. We used the NMES signal itself to assess the quality of the electrode-skin contact and the electrical properties of the underlying tissues over a week. A 14% decrease in the skin&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s stratum corneum resistance (from 20 to 17 kΩ) and a 15% decrease in the resistance of the electrodes and underlying tissues (from 550 to 460 Ω) were observed in the 14 healthy subjects investigated. A follow-on investigation of the effect of exercise-induced sweating on the electrical properties of the electrode-skin-underlying tissue composite during NMES indicated a correlation between the decrease in the resistance values observed over the course of the week and the accumulation of sweat at the electrode-skin interface. The value of the capacitance representing the dielectric properties of the skin&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s stratum corneum increased after exercise-induced sweating but did not change significantly over the course of the week. We conclude that valuable information about the electrode-skin-underlying tissue composite can be gathered using the NMES signal itself, and suggest that this is a practical, safe and relatively simple method for monitoring these electrical properties during long-term stimulation.

The skin's electrical asymmetry

Journal of Physics: Conference Series, 2009

ABSTRACT We studied the asymmetry of skin response to a constant current pulse (4mA/0.1ms) of pos... more ABSTRACT We studied the asymmetry of skin response to a constant current pulse (4mA/0.1ms) of positive or negative polarity, followed by a free decay of skin&#39;s potential. Negative polarity pulse is related with a lower skin resistance and higher electrical capacity. This behavior corresponds to 2 of the 3 relaxation times found in our skin measurements.

The local structure of europium–lead-borate glass ceramics

Journal of Molecular Structure, 2009

Glass ceramics in the xEu 2 O 3 (100 À x)[3B 2 O 3 ÁPbO] system with 0 6 x 6 50 mol% have been pr... more Glass ceramics in the xEu 2 O 3 (100 À x)[3B 2 O 3 ÁPbO] system with 0 6 x 6 50 mol% have been prepared using the melt quenching method, succeeded by heat treatment applied at 625°C and 675°C, respectively, for 48 h. The influence of europium ions on structural behavior of the lead-borate glass ceramics has been investigated using infrared spectroscopy and DFT calculations. The addition of europium ions into the host glass ceramics matrix leads to an increase of the glass network polymerization due to the replacement of BAOAB bonds by the more resistant BAOAPb bonds. The structural evolution of the studied glass ceramics with the gradual increase of the europium oxide content up to 50 mol% could be explained by considering that the excess of oxygen may be accommodated by the formation of [PbO 4 ] structural units. Then, the formation of different ionic complexes of the lead ions will decrease the rate of crystal growth and the conversion of the glass into crystalline material becomes more difficult, in agreement to the X-ray data.

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An Electrical View of the Skin

Some features of the electrical behavior of the human skin, mainly obtained by a pulse method mes... more

Controlled iontophoresis for medical applications

ie.utcluj.ro

... Romania, Medical Engineering, e-mail: [email protected]. E. Culea is with the Technic... more

Semiconductor Gas Sensor for Detecting Air Pollution

clean air

SEMICONDUCTOR GAS SENSOR FOR DETECTING AIR POLLUTION. Nicolae-Marius BÂRLEA, Sînziana Iulia BÎRLE... more

The Importance of the Skin Galvanic Response on Certain Points

itim-cj.ro

THE IMPORTANCE OF THE SKIN GALVANIC RESPONSE ON CERTAIN POINTS. Nicolae-Marius BÂRLEA, Adina MAN.... more

Electrical detection of acupuncture points

Acta Electrotech Napocensos, 2000

ABSTRACT: Comparative total impedance measurements for normal skin and acupuncture points are pre... more

Detecting Electroporation by Assessing the Time Constants in the Exponential Response of Human Skin to Voltage Controlled Impulse Electrical Stimulation

2009 Annual International Conference of the Ieee Engineering in Medicine and Biology Society, Vols 1-20, 2009

We propose a new method for extracting the electrical properties of human skin based on the time ... more We propose a new method for extracting the electrical properties of human skin based on the time constant analysis of its exponential response to impulse stimulation. As a result of this analysis an adjacent finding has arisen. We have found that stratum corneum electroporation can be detected using this analysis method. We have observed that a one time-constant model is appropriate for describing the electrical properties of human skin at low amplitude applied voltages (&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;30V), and a two time-constant model best describes skin electrical properties at higher amplitude applied voltages (&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;30V). Higher voltage amplitudes (&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;30V) have been proven to create pores in the skin&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s stratum corneum which offer a new, lower resistance, pathway for the passage of current through the skin. Our data shows that when pores are formed in the stratum corneum they can be detected, in-vivo, due to the fact that a second time constant describes current flow through them.

Determination of the Electrical Parameters of Some ECG Electrodes

by Marius Barlea and Rares Iusan

— In this paper we verify if ECG electrodes are adequate for the bioimpedance measurement. A squa... more — In this paper we verify if ECG electrodes are adequate for the bioimpedance measurement. A square wave signal (U=1V, f=5, 500, 5000 Hz) is applied to a calibrated resistance R=10 kΩ, in series with two identical ECG electrodes glued together by their adhesive part. Using an appro-piate model, we find from the data a series resistance with one or more groups of a parallel resistance R i with a capacitor C i (i=1, 2, 3).

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How to Describe the Skin's Electrical Nonlinear Response

by Marius Barlea and Sînziana Bîrlea

—The skin's electrical nonlinearities found experimentally are related to stratum corneum and mod... more —The skin's electrical nonlinearities found experimentally are related to stratum corneum and modeled by the parallel resistance (Rp) as a linear current dependence in con-ductance (1/Rp). We show that such dependence could occur because the skin's current-voltage characteristic has a non-ohmic linear portion at large voltage, due to pores' conduction, that can be detected as a constant dynamic resistance (dU/dI).

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How to Describe the Skin’s Electrical Nonlinear Response

International Conference on Advancements of Medicine and Health Care through Technology; 12th - 15th October 2016, Cluj-Napoca, Romania, 2017

Aplication of Blade Electrodes in Electroporation and his Importance in Electrical Properties of Skin

2019 11th International Symposium on Advanced Topics in Electrical Engineering (ATEE), 2019

Determination of the Electrical Parameters of Some ECG Electrodes

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Electrical methods for testing building and construction materials

Water as a Third Compartment within the Skin’s Stratum Corneum

IFMBE Proceedings, 2014

Model of the Current-Voltage Relation for a Skin Pore

IFMBE Proceedings, 2011

The Skin’s Electrical Time Constants

IFMBE Proceedings, 2011

Shaping traffic flow with a ratio of time constants

Central European Journal of Engineering, 2014

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The current-voltage relation of a pore and its asymptotic behavior in a Nernst-Planck model

Journal of Electrical Bioimpedance, 2012

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Changes in the electrical properties of the electrode–skin–underlying tissue composite during a week-long programme of neuromuscular electrical stimulation

Physiological Measurement, 2014

The skin's electrical asymmetry

Journal of Physics: Conference Series, 2009

The local structure of europium–lead-borate glass ceramics

Journal of Molecular Structure, 2009

Download

An Electrical View of the Skin

Some features of the electrical behavior of the human skin, mainly obtained by a pulse method mes... more

Controlled iontophoresis for medical applications

ie.utcluj.ro

... Romania, Medical Engineering, e-mail: [email protected]. E. Culea is with the Technic... more

Semiconductor Gas Sensor for Detecting Air Pollution

clean air

SEMICONDUCTOR GAS SENSOR FOR DETECTING AIR POLLUTION. Nicolae-Marius BÂRLEA, Sînziana Iulia BÎRLE... more

The Importance of the Skin Galvanic Response on Certain Points

itim-cj.ro

THE IMPORTANCE OF THE SKIN GALVANIC RESPONSE ON CERTAIN POINTS. Nicolae-Marius BÂRLEA, Adina MAN.... more

Electrical detection of acupuncture points

Acta Electrotech Napocensos, 2000

ABSTRACT: Comparative total impedance measurements for normal skin and acupuncture points are pre... more

Detecting Electroporation by Assessing the Time Constants in the Exponential Response of Human Skin to Voltage Controlled Impulse Electrical Stimulation

2009 Annual International Conference of the Ieee Engineering in Medicine and Biology Society, Vols 1-20, 2009

Determination of the Electrical Parameters of Some ECG Electrodes

by Marius Barlea and Rares Iusan

Download

How to Describe the Skin's Electrical Nonlinear Response

by Marius Barlea and Sînziana Bîrlea

Download

Changes in the electrical properties of the electrode–skin–underlying tissue composite during a week-long programme of neuromuscular electrical stimulation

by Gearóid ÓLaighin and Marius Barlea

Particular neuromuscular electrical stimulation (NMES) applications require the use of the same e... more Particular neuromuscular electrical stimulation (NMES) applications require the use of the same electrodes over a long duration (>1 day) without having access to them. Under such circumstance the quality of the electrode–skin contact cannot be assessed. We used the NMES signal itself to assess the quality of the electrode–skin contact and the electrical properties of the underlying tissues over a week. A 14% decrease in the skin's stratum corneum resistance (from 20 to 17 k) and a 15% decrease in the resistance of the electrodes and underlying tissues (from 550 to 460) were observed in the 14 healthy subjects investigated. A follow-on investigation of the effect of exercise-induced sweating on the electrical properties of the electrode–skin– underlying tissue composite during NMES indicated a correlation between the decrease in the resistance values observed over the course of the week and the accumulation of sweat at the electrode–skin interface. The value of the capacitance representing the dielectric properties of the skin's stratum corneum increased after exercise-induced sweating but did not change significantly over the course of the week. We conclude that valuable information about the electrode–skin–underlying tissue composite can be gathered using the NMES signal itself, and suggest that this is a practical, safe and relatively simple method for monitoring these electrical properties during long-term stimulation.

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