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JournalISSN: 0140-0118

Medical & Biological Engineering & Computing 

Springer Science+Business Media
About: Medical & Biological Engineering & Computing is an academic journal published by Springer Science+Business Media. The journal publishes majorly in the area(s): Medicine & Computer science. It has an ISSN identifier of 0140-0118. Over the lifetime, 7307 publications have been published receiving 178013 citations. The journal is also known as: Medical and biological engineering and computing (Online) & Medical & biological engineering & computing (Print).


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Journal ArticleDOI
TL;DR: The various applications of HRV and different linear, frequency domain, wavelet domain, nonlinear techniques used for the analysis of the HRV are discussed.
Abstract: Heart rate variability (HRV) is a reliable reflection of the many physiological factors modulating the normal rhythm of the heart. In fact, they provide a powerful means of observing the interplay between the sympathetic and parasympathetic nervous systems. It shows that the structure generating the signal is not only simply linear, but also involves nonlinear contributions. Heart rate (HR) is a nonstationary signal; its variation may contain indicators of current disease, or warnings about impending cardiac diseases. The indicators may be present at all times or may occur at random-during certain intervals of the day. It is strenuous and time consuming to study and pinpoint abnormalities in voluminous data collected over several hours. Hence, HR variation analysis (instantaneous HR against time axis) has become a popular noninvasive tool for assessing the activities of the autonomic nervous system. Computer based analytical tools for in-depth study of data over daylong intervals can be very useful in diagnostics. Therefore, the HRV signal parameters, extracted and analyzed using computers, are highly useful in diagnostics. In this paper, we have discussed the various applications of HRV and different linear, frequency domain, wavelet domain, nonlinear techniques used for the analysis of the HRV.

2,344 citations

Journal ArticleDOI
TL;DR: It is concluded that the patient's skin should be abraded to reduce impedance, and measurements should be avoided in the first 10 min after electrode placement, to allow satisfactory images.
Abstract: A computer simulation is used to investigate the relationship between skin impedance and image artefacts in electrical impedance tomography. Sets of electrode impedance are generated with a pseudo-random distribution and used to introduce errors in boundary voltage measurements. To simplify the analysis, the non-idealities in the current injection circuit are replaced by a fixed common-mode error term. The boundary voltages are reconstructed into images and inspected. Where the simulated skin impedance remains constant between measurements, large impedances (> 2k omega) do not cause significant degradation of the image. Where the skin impedances 'drift' between measurements, a drift of 5% from a starting impedance of 100 omega is sufficient to cause significant image distortion. If the skin impedances vary randomly between measurements, they have to be less than 10 omega to allow satisfactory images. Skin impedances are typically 100-200 omega at 50 kHz on unprepared skin. These values are sufficient to cause image distortion if they drift over time. It is concluded that the patient's skin should be abraded to reduce impedance, and measurements should be avoided in the first 10 min after electrode placement.

1,976 citations

Journal ArticleDOI
TL;DR: In this procedure, essentially nothing is assumed about the source currents, except that they are spatially restricted to a certain region, and the results can describe the structure of the current flow fairly well.
Abstract: The authors have applied estimation theory to the problem of determining primary current distributions from measured neuromagnetic fields. In this procedure, essentially nothing is assumed about the source currents, except that they are spatially restricted to a certain region. Simulation experiments show that the results can describe the structure of the current flow fairly well. By increasing the number of measurements, the estimate can be made more localised. The current distributions may be also used as an interpolation and an extrapolation for the measured field patterns.

1,796 citations

Journal ArticleDOI
TL;DR: The paper traces the history of, and tabulates determinations of the electrical resistivity of blood, other body fluids, cardiac muscle, skeletal muscle, lung, kidney, liver, spleen, pancreas, nervous tissue, fat, bone, and other miscellaneous tissues.
Abstract: The paper traces the history of, and tabulates determinations of the electrical resistivity of blood, other body fluids, cardiac muscle, skeletal muscle, lung, kidney, liver, spleen, pancreas, nervous tissue, fat, bone, and other miscellaneous tissues. Where possible, the conditions of measurement are given.

1,645 citations

Journal ArticleDOI
TL;DR: The design and performance of an instrument that has been developed to apply the technique of near-infra-red spectroscopy to the monitoring of the brain in newborn infants are described.
Abstract: The technique of near-infra-red spectroscopy allows safe continuous monitoring of changes in blood and tissue oxygenation on an intact organ This is made possible by observing spectral changes in the tissues caused by oxygenated haemoglobin [HbO2], deoxygenated haemoglobin [Hb] and cytochrome aa3 [Cyt aa3] The paper describes the design and performance of an instrument that has been developed to apply this technique to the monitoring of the brain in newborn infants The instrument monitors optical transmission changes across a newborn infant's brain at four wavelengths A standard deviation in error of 1 per cent (0·01 optical density OD) is achieved on measurements of transmission changes at 20s intervals This performance is obtained at a mean attenuation of 10 OD, the approximate attenuation across a term infant's head Long-term monitoring is possible as instrumental drift is less than 0·004 OD per hour

941 citations

Performance
Metrics
No. of papers from the Journal in previous years
YearPapers
2023137
2022268
2021188
2020214
2019200
2018183