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Comparison of cardiac time intervals between echocardiography and impedance cardiography at various heart rates

, various physiological models and algorithms were used, e.g. by Sramek et al. and Bernstein [ 2 , 3 , 4 ]. Most of the estimates of SV were essentially based on the assumptions that the C-wave originates from small fluctuations in a simply distributed electrical field caused by blood volume changes or velocity changes in the aorta. Meanwhile, several studies have shown that these assumptions are too simplistic [ 5 , 6 , 7 , 8 , 9 ]. Therefore, it appears to be futile to make an interpretation of the amplitude of the ICG-signal based on simplistic models. A

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A LabVIEW-based electrical bioimpedance spectroscopic data interpreter (LEBISDI) for biological tissue impedance analysis and equivalent circuit modelling

, 25 , 26 ] reveal the impedance response of biological tissues at one, two or more specified frequencies (f). EIS has been proven as an effective technique for noninvasive tissue characterization in medical, biomedical and biological applications [ 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 ]. Because EIS is a more generalized method that provides impedance variations over a wide range of frequencies, it can be used on its own to provide information that explains other bioelectrical phenomena like dielectric polarization [ 37 , 38 , 39 , 40 , 41

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Improving Conductivity Image Quality Using Block Matrix-based Multiple Regularization (BMMR) Technique in EIT: A Simulation Study

system has, generally, poor signal to noise ratio [ 19 ] and poor spatial resolution [ 20 ] due to the factors associated with it. The boundary data profile [ 21 ] of the practical phantom [ 22 , 23 , 24 , 25 , 26 ] is highly sensitive to modeling parameters [ 27 ] such as the phantom structure [ 23 , 26 ], surface electrodes geometry [ 21 ], experimental errors [ 23 , 26 , 28 ] and errors of the EIT-instrumentation [ 29 , 30 , 31 , 32 ]. That is why there are a number of opportunities and challenges in EIT to make this technology as an efficient medical

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Impedance of tissue-mimicking phantom material under compression

readings, all did so under steady-state conditions, disregarding the dynamic relaxation behavior of the tissue under consideration. In this study, we consider the relationship between the viscoelastic behavior of a phantom material – namely tofu – to its measured bioimpedance in real-time. Tofu has become a popular phantom material in many fields of biological interest including elastography ( 24 ) and ultrasound imaging ( 25 ). Tofu, also referred to as bean curd, is a food made by pressing curds from coagulated soymilk into blocks of relative homogeneity. Coagulation

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Studies in Rheoencephalography (REG)

The brain has ongoing, substantial energy requirements but minimal stores of energy-generating substrates. As a result, it is completely dependent on a continuous, uninterrupted supply of substrate (oxygen, glucose). Although the demand by the brain for energy-generating substrates is substantial (the central nervous system consumes 20% of the oxygen (that is, 170 mmol/l00 g per min or 3-5 ml O 2 /100 g brain tissue per mm or, approximately, 40-70 ml O 2 /min) and 25% of the glucose (31 mmol/l00 g per mm) utilized by the resting individual under physiological

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Peripheral vein detection using electrical impedance method

lists the electrical resistivity of forearm biological tissues at a frequency of 100 kHz [ 6 ]. Table 1 The electrical resistivity of forearm biological tissues. Tissue Electrical resistivity ρ [Ωm] Muscle tissue 2.76 ± 0.3 Connective tissue 2.5 ± 0.5 Blood 1.42 ± 0.6 Nerve 12.5 ± 0.5 Subcutaneous fat 25 ± 0.7 Blood vessel wall 3.13 ± 0.2 Materials and methods To perform electrical impedance measurements, a special electrode system was designed to be attached to the study area. The electrode system

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A short tutorial contribution to impedance and AC-electrokinetic characterization and manipulation of cells and media: Are electric methods more versatile than acoustic and laser methods?

, Schnelle T, Fuhr G. Dielectrophoretic sorting of particles and cells in a microsystem. Anal. Chem. 1998, 70: 1909-1915. http://dx.doi.org/10.1021/ac971063b 10.1021/ac971063b Fiedler S Shirley SG Schnelle T Fuhr G Dielectrophoretic sorting of particles and cells in a microsystem Anal. Chem 1998 70 1909 – 1915 http://dx.doi.org/10.1021/ac971063b Foster KR, Schwan HP. 1996, Dielectric properties of tissues. Handbook of biological effects of electromagnetic fields. Polk C, Postow E (Eds.) CRC Press Inc., Boca Raton, FL. 25-102. Foster KR

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Electrical impedance myography for assessing paraspinal muscles of patients with low back pain

attributable to a spinal etiology as determined by board-certified physiatrist (J.K.). Exclusion criteria included, history of a generalized neuromuscular condition, except for mild polyneuropathy or common mononeuropathies (e.g., carpal tunnel syndrome, ulnar neuropathy at the elbow), history of moderate-to-severe ongoing medical conditions producing generalized disability, such as advanced cardiac or renal disease, metal spine implants of any type. For healthy subjects, the exclusion criteria included the above items as well as a history of present or past disabling back

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Electrical characterization of bolus material as phantom for use in electrical impedance and computed tomography fusion imaging

in radiation therapy were considered in the present study. The first sample, Sample 1, was the commercially available material Superflab made of 100% Akton® viscoelastic polymer; it is a low cost, well conforming material with a tissue equivalent dose absorption properties and density of 1.03 g/cc. The second sample, Sample 2, was an in-house developed material Gelatin Bolus made of gelatin (Benson Foods Ltd., Gelatine 175 Bloom). The gelatin is manufactured using pig skin and has 2% sodium by weight. Ten sub-samples of each sample were used for cross validation of

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Dielectrical properties of living epidermis and dermis in the frequency range from 1 kHz to 1 MHz

OCT [16] 65.1±8.9 8 31 - 37 OCT [17] SC (μm) 12.9±3.8 6 25 - 31 TEWL/Stripping [18] 12.3±3.6 6 33.2±3.1 TEWL/Stripping [19] 9.58±0.8 10 23 - 47 Reflectance CM [12] 10.4±3.2 13 18 - 25 CLSM [20] 22.6±4.33 14 23 - 49 CRS [21] 18±3.9 14 28 - 50 CRS [22] 10.4±0.9 9 23 - 55 OCT [22] 13.07±2.12 19 20 - 29 OCT [16] 18±2 2 23 - 25 CRS [23] DE (mm) 1.02±0.10 44 21 - 30 US 20MHz B scanner [24] 1

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