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Modeling and Simulation of Equivalent Circuits in Description of Biological Systems - A Fractional Calculus Approach

interest only to mathematicians. On the other hand, many physical phenomena have "intrinsic" fractional order descriptions and so FC is necessary in order to explain them. In many applications FC provides more accurate models of the physical systems than ordinary calculus does. Because of its success in description of anomalous diffusion [ 16 , 17 , 18 ], non-integer order calculus both in one and multidimensional space, has become an important tool in many areas of physics, mechanics, engineering, and bioengineering [ 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26

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Probing for stomach using the Focused Impedance Method (FIM)

model as shown in Figure 2 . The trunk was simulated by a vertical rectangular parallelepiped with rounded edges on all four sides. The horizontal dimensions chosen were 30 cm (representing trunk breadth, x-axis) and 25 cm (representing trunk thickness or depth, y-axis) while the vertical dimension was chosen at 40 cm (representing trunk height, z-axis). The radii of curvature for rounding of the rectangle at the corners were made greater on the assumed back of the body compared to that for the front; the values arbitrarily chosen at 8 cm and 5 cm respectively. This

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Electrical Impedance Spectroscopic Studies on Broiler Chicken Tissue Suitable for the Development of Practical Phantoms in Multifrequency EIT

in several aspects. Saline or any other salt solutions are purely resistive materials and hence the multifrequency EIT systems [ 1 , 22 , 23 , 24 ] cannot be studied properly with saline phantoms because the responses of the purely resistive materials do not change over frequency. On the other hand, electrical impedance of biological materials is a complex quantity [ 25 , 26 ] which is a function of tissue composition as well as the frequency of the applied ac signal [ 27 ]. The Protein-Lipid-Protein structure [ 28 ] of the membrane of a biological cell gives a

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Testing miniaturized electrodes for impedance measurements within the β-dispersion – a practical approach

miniaturized electrodes. Today, almost any electrode shape and size even down to molecular level are feasible [ 25 ; 26 ]. Based on theoretical prediction, like FEM (finite element method), most researchers are today sure about the behavior of the electrode systems in use [ 27 ]. Problems are not always obvious. For instance, the simulation of the field distribution at equally shaped electrodes but with different size yields the same pictures. But calculating the geometry factor d/A (distance / surface area) for a simple electrode geometry reveals marked differences. For

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Statistical methods for bioimpedance analysis

the whole population. In order to make a general conclusion about the population, we need to show that the effect that we observed was not likely due to chance from random variation in our sample. If we choose too few units, we may end up with an inconclusive result and a worthless study, and if we choose too many, we are wasting resources (e.g. sacrificing more animals than needed). Hence, sample size consideration is of ethical relevance [ 2 ]. In hypothesis testing, we want to reduce the chances of two types of errors: incorrectly rejecting a true null

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

Kuyucak S Charge state of the fast gate in chloride channels: Insights from electrostatic calculations in a schematic model The Journal of Chemical Physics 2007 127 195102 http://dx.doi.org/10.1063/1.2804419 24 Chang HC, Yossifon G. Understanding electrokinetics at the nanoscale: A perspective. Biomicrofluidics. 2009; 3:0120011--15. http://dx.doi.org/10.1063/1.3056045 19693382 Chang HC Yossifon G Understanding electrokinetics at the nanoscale: A perspective Biomicrofluidics 2009 3 0120011--15 http://dx.doi.org/10.1063/1.3056045 25

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Estimating electrical properties and the thickness of skin with electrical impedance spectroscopy: Mathematical analysis and measurements

Introduction The human skin is essentially composed of three layers – stratum corneum, living epidermis and dermis – that fulfill a range of important functions, such as acting as a mechanical and chemical barrier against the environment and upholding homeostasis by regulating water loss. The thickness of each layer varies naturally between and within individuals due to a number of biological and environmental factors: e.g., age, body site, season, race, humidity, diurnal cycle, and health condition. It is not straightforward to measure the skin thickness

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Improvement of wireless transmission system performance for EEG signals based on development of scalar quantization

}} \\ \end{align}$$ (15) S N R = 10 l o g ( σ s 2 / σ q 2 ) , $$SNR=10log\left( {\sigma _{s}^{2}}/{\sigma _{q}^{2}}\; \right),$$ where (σ q 2 ) is Mean Squared Quantization Error. Table 1 shows estimated MSQE for different number of bits per samples, 5<N<20, of a uniform quantizer, a BGAI quantizer and a BUIA quantizer. Table 1 The comparison among calculated MSQE of proposed methods and uniform quantizer. Bits per sample Uniform Quantizer (MSQE) BGAI Quantizer MSQE BUAI Quantizer MSQE 5 -104.29 dB -109.86 dB -118.64 dB

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Marking 100 years since Rudolf Höber’s discovery of the insulating envelope surrounding cells and of the β-dispersion exhibited by tissue

from 11 experiments was that the internal conductivity of red blood cells was equivalent to a 0.18% NaCl solution (minimum 0.11%, maximum 0.3%). He noted that this represented about 1/3 to 2/3 of that of the conductivity of blood serum or of Ringer’s solution. He reviewed the argument made by others that the reason why blood corpuscles, like many other cells, contain salts in other concentrations to those of their surroundings results from some of them being bound to organic components within the cell. He argues that the experiments he has presented provide proof

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Analysis of a Mechanistic Model for Non-invasive Bioimpedance of Intact Skin

{J}}_{z}}}{\partial \widetilde{z}}=0,$$ subject to the boundary conditions adjacent to the electrodes (24) Φ ˜ ( I ) = 0 , $$\widetilde{\Phi }\left( \text{I} \right)=0,$$ (25) Φ ( II ) = 1 , $$\Phi \left( \text{II} \right)=1,$$ and a continuous potential at the interface with the viable skin (N.B.: the potential drop in the electrodes is negligible at leading order as we shall show later). The current between the inject and the sense in the radial direction thus has to occur in the viable skin and/or adipose tissue, because the voltage is not enough to

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