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M. Amini, J. Hisdal and H. Kalvøy

the tissue engineered constructs. However, these methods such as histology staining, are destructive and time-consuming and require fixing and cutting the tissue cultures ( 6 ). Therefore, there is a need for real-time and noninvasive monitoring techniques to evaluate the quality of the tissue engineered constructs before implanting them in the body, without the need to use fluorescents or radioactive labels or destructive methods. This in addition, would reduce the number of animals required for this purpose ( 5 , 6 ). Bioimpedance Measurements Basics of

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Jaan Ojarand and Mart Min

frequency components in it, decreases as well. In electrical bioimpedance (EBI) measurements, unfortunately, the SNR cannot be improved by increasing the overall amplitude of the summary excitation signal, since it is limited to low values because of both two issues: a) satisfying the criteria of linearity of the LTI systems and b) fulfilling the security needs for living tissues [ 3 ], [ 4 ]. Even for non-biologic measurements, the allowable input signal range and power supply voltage of electronic components, both limit the allowed amplitude of signals. Moreover, due

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Douglas Dutra and Pedro Bertemes-Filho

the field of electrical impedance spectroscopy [ 18 ], but also other properties of some materials, such as optical [ 19 ], mechanical and acoustic [ 20 ], anisotropy and viscoelasticity [ 21 ], thermal [ 22 ] and dielectric [ 23 ]. Most EIS system use the Cole model [ 24 , 25 ] for tissue characterization. This is a non-integer (0 < α < 1) polynomial function (see equation 1 ) which best describes the biological sample. Different biological samples have a different α number. Most bioimpedance analysis consist of a resistance at zero frequency (RR 0 ), a

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Michael Bodo, Leslie D. Montgomery, Frederick J. Pearce and Rocco Armonda

predicted a better patient outcome than intermittent monitoring ( Rivere-Lala et al, 2017 ). Background of Rheoencephalography (REG) The term ‘rheoencephalography’ was first applied by Jenkner (1962) to refer to the use of bioimpedance to estimate brain circulation. According to the US Food and Drug Administration (FDA), "a rheoencephalograph is a device used to estimate a patient’s cerebral circulation by electrical impedance methods with direct electrical connections to the scalp or neck area" ( Anonymous, 1997 ). The original REG device was a four

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Nermin Öztürk, Esin Ozturk-Isik and Yekta Ülgen

the bone mineral density of total body through the hip or lumbar spine. The forecast of hip fracture is performed effectively by measuring both hip and lumbar spine regions; as hips are the most effective regions for fracture comparisons [ 12 , 13 , 14 ]. Body bioimpedance characteristics are a function of body composition as well as bone mineral content. With foot to foot, single frequency (50 kHz, 0.8 mA) bioimpedance measurements of the whole body in postmenopausal women (42 – 84 years) and men (42 – 94 years), it was shown that the bioimpedance was

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Fred J. Pettersen

, such as a bioimpedance system, sensitivity takes another meaning as explained below. A short repetition of some of the mathematics involved is useful in order to explain the problem. For those requiring more detailed information on the subject, the book Bioimpedance and Bioelectricity Basics [ 1 ] is recommended. If we look at an impedance measurement system with separated current carrying (CC) electrode pair and potential pick-up (PU) electrode pair, the measured transfer impedance is the potential on the PU electrodes divided by the current flowing in the CC

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Robert Brajkovič, Tomaž Žagar and Dejan Križaj

. Technical report 004/83. Solartron Instrumentation Group. [5] Grimnes, S., Martinsen, O. (2000). Bioimpedance and Bioelectricity Basics , Academic Press. [6] Horowitz, P., Hill, W. (1996). The Art of Electronics, Second edition . Cambridge University Press. [7] Iacopini, E., Smith, B., Stefanini, G., Carusotto, S. (1983). Digital techniques applied to phase-sensitive detection. Journal of Physics E: Scientific Instruments , 16, 844-847. [8] Križaj, D., Baloh, M., Brajkovič, R., Žagar, T. (2013). Design and development of a portable WiFi enabled BIA device

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Vinicius G Sirtoli, Kaue F Morcelles and Volney C Vincence

Introduction Electrical Bioimpedance Spectroscopy (EBIS) is a technique to assess passive electrical properties of a biological material [ 1 ]. It can be invasive, non-invasive or a combination of both. To measure the bioimpedance, it is injected an electrical signal and acquired the biological material electrical response. There are many applications of EBIS, and a lot of them involve the diagnosis of diseases such as skin cancer [ 2 ], pressure ulcer [ 3 ] and brain cellular edema [ 4 ]. Highly precise instruments for both signal generation and acquisitions

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Ramon Pallàs Areny

It is often (wrongly) assumed or implied that tetrapolar bioimpedance measurements convey the same advantage than the four-wire resistance measurement method proposed by Lord Kelvin, namely, minimizing the influence of the leads that connect the resistance under test (RUT) to the measurement instruments, which is mostly beneficial in low-value resistance measurements. Tetrapolar bioimpedance measurements reduce, rather than minimize, the effect of electrode impedances but they suffer from concomitant undesired effects mainly attributable to moving from: 1) DC

Open access

J. Rosina, Jana Vranova, Ondrej Remes, Katarina Nehezova and I. Rychlik

water using impedance loci generated by multiple frequency bioelectric impedance analysis. Phys Med Biol 38:337-346, 1993 Foster K. R., Schawn H. P., ‘Dielectric properties of tissues and biological materials: a critical review’, CRC Critical Reviews in Biomedical Engineering, vol. 17, no. 1, 25-104, 1989 Ivorra A.: Bioimpedance monitoring for physicians: an overview. Hospital Clinic de Barcelona, July 2003 Adohi B. J.-P., Vanga Bouanga C., Fatyeyeva K., Tabellout M.: Application of the