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Questioning the aloe vera plant and apple memristors

(three electrode system that enables monopolar recordings and silver/silver chloride (Ag/AgCl) electrodes). We also used transimpedance amplifiers for the reading of the current instead of single resistors in series. Furthermore, we recorded simultaneously with a stainless steel needle electrode to compare also with the results of Volkov et al . who used coated platinum needle electrodes. We found that dependent on which electrode type was used, there are large differences in the results and two possible explanations arise. If the recorded non-linear electrical

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The non-linear electrical properties of silver/silver chloride electrodes in sodium chloride solution

supplementary information Figs. S1 to S4 ). Finally, we did some additional measurements on the forehead of one test subject that allow for a direct comparison with the recordings in the sodium chloride solution. Materials and methods All measurements were done at the University of Oslo. Instrumentation The recordings were done by the use of a custom built measurement system (see Fig. 1b and [ 4 ]). The setup contains a DAQ card (NI USB-6356) which is connected to a computer and controlled by a custom made program based on LabVIEW 2018. A three electrode

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Impedance detection of the electrical resistivity of the wound tissue around deep brain stimulation electrodes permits registration of the encapsulation process in a rat model

Education and Research (BMBF, FKZ 01EZ0911). The custom-made stimulator system was developed in cooperation with the Steinbeis company (STZ1050, Rostock, Germany) and Dr. R. Arndt (Rückmann & Arndt, Berlin, Germany). References 1 Krack P, Hariz MI, Baunez C, Guridi J, Obeso JA. Deep brain stimulation: from neurology to psychiatry? Trends Neurosci. 2010;33:474-84. https://doi.org/10.1016/j.tins.2010.07.002 20832128 10.1016/j.tins.2010.07.002 Krack P Hariz MI Baunez C Guridi J Obeso JA Deep brain stimulation: from neurology to psychiatry

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Monitoring Change of Body Fluid during Physical Exercise using Bioimpedance Spectroscopy and Finite Element Simulations

magnetic field strength (h) are assigned to the edges. Hence, a system of equations, called Maxwell-Grid Equations, has to be solved for the whole calculation domain, where each cell is described by: (1) C e → = − ∂ b → ∂ t                                   C ˜ h → = − ∂ d → ∂ t + j → $$C\overrightarrow{e}=-\frac{\partial \overrightarrow{b}}{\partial t}\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \tilde{C}\overrightarrow{h}=-\frac{\partial \overrightarrow{d}}{\partial t}+\overrightarrow{j}$$ (2) S ˜ d → = q                 S b → = 0 $$\tilde

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Significance of biological membranes for accurate computational dosimetry of low frequency electric fields

, and to attain this field in specific regions of the brain, the electric current should pass through different head layers via skin, fat, skull, meninges, and cortex (part of the brain). In order to model the brain, different layers should be considered, including gray and white matters. The meninges, three layers of protective tissue, cover the outer surface of the central nervous system (brain and spinal cord) and comprise three connective tissue layers viz. (from the innermost to the outermost layer) the pia mater, arachnoid and the dura mater. The meninges also

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Mechanistic multilayer model for non-invasive bioimpedance of intact skin

electrodes are near-to constant because of the high resistance to current of the stratum corneum in the considered frequency range [ 3 ]. This allows us to rewrite the boundary conditions, Eqs. 5 - 7 , between the probe and the uppermost skin layer n , stratum corneum, as (we drop the subindex ` eff ’ for notational convenience in the analysis) − σ n ∂ Φ ( r , H n ) ∂ z = ∑ j = 1 m I j A j [ U ( R 2 j − 1 − r ) − U ( R 2 j − 2 − r ) ] , $$\begin{array}{} \displaystyle -\sigma_{n}\frac{\partial\Phi(r,\mathcal{H}_{n})}{\partial z}=\sum_{j=1}^{m

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