Journal of Electrical Bioimpedance最新文献

{"title":"Introducing the Hybrid \"K-means, RLS\" Learning for the RBF Network in Obstructive Apnea Disease Detection using Dual-tree Complex Wavelet Transform Based Features.","authors":"Javad Ostadieh, Mehdi Chehel Amirani","doi":"10.2478/joeb-2020-0002","DOIUrl":"10.2478/joeb-2020-0002","url":null,"abstract":"<p><p>Apnea is one of the deadliest diseases that can be prevented and cured if it is detected in time. In this paper, we propose a precise method for early detection of the obstructive sleep apnea (OSA) disease using the latest feature selection and extraction methods. The feature selection in this paper is based on the Dual tree complex wavelet (DT-CWT) coefficients of the ECG signals of several patients. The feature extraction from these coefficients is done using frequency and time techniques. The Feature selection is done using the spectral regression discriminant analysis (SRDA) algorithm and the classification is performed using the hybrid RBF network. A hybrid RBF neural network is introduced in this paper for detecting apnea that is much less computationally demanding than the previously presented SVM networks. Our findings showed a 3 percent improvement in the detection and at least a 30 percent reduction in the computational complexity in comparison with methods that have been presented recently.</p>","PeriodicalId":38125,"journal":{"name":"Journal of Electrical Bioimpedance","volume":" ","pages":"4-11"},"PeriodicalIF":0.0,"publicationDate":"2020-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/1b/27/joeb-11-004.PMC7531097.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25368389","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fast Electrical Characterization with Low Hardware Requirement.","authors":"Uwe Pliquett","doi":"10.2478/joeb-2020-0001","DOIUrl":"https://doi.org/10.2478/joeb-2020-0001","url":null,"abstract":"Electrical impedance spectroscopy can be performed using a great variety of methods and instrumentation. The most popular method, sweeping though a frequency range and measuring the impedance, either magnitude and phase or real and imaginary part at each desired frequency, offers high precision due to selective amplifiers and high dynamic range with respect to impedance magnitude. Highly sophisticated laboratory equipment guarantees robust measurement while software packages assist the interpretation of the measurement results. Although automated impedance analyzers are reasonably fast, the physical limitation of signal engagement at each measurement frequency always applies. Traditionally, the majority of the impedance analyzers are bulky and expensive and thus not suited for process instrumentation. During the last two decades, more and more economic instruments with small dimensions and low energy constraints conquer the market. Although the majority of these devices work in the frequency domain, time domain based approaches are increasingly offered.","PeriodicalId":38125,"journal":{"name":"Journal of Electrical Bioimpedance","volume":" ","pages":"1-3"},"PeriodicalIF":0.0,"publicationDate":"2020-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/ae/85/joeb-11-001.PMC7531099.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25368388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Segmental Volume Changes that Occur in Nonhuman Primates During Short Term Head Up (HUT) and Head Down (HDT) Tilt.","authors":"Leslie David Montgomery,&nbsp;Clarence Oloff","doi":"10.2478/joeb-2020-0003","DOIUrl":"https://doi.org/10.2478/joeb-2020-0003","url":null,"abstract":"<p><p>Nonhuman primates are often used in biomedical research and to investigate physiologic processes that occur in man. Impedance plethysmography was used to measure calf, thigh, pelvic, abdominal, and thoracic volume changes in ten Rhesus and eight squirrel monkeys during five-minute exposures to HUT and HDT at angles of 5, 10, and 20 degrees. Calf, rump and tail measurements were made in three squirrel monkeys at 10 and 20 degrees of HUT and HDT. Fluid volume changes in all segments of the Rhesus monkeys were found to change during HUT an HDT in direct relation to the angle of tilt used. However, the volume changes that occurred in the squirrel monkeys were found to be quite different. Their calf, thigh, and pelvic segments lost volume during both HUT and HDT while their abdominal and thoracic segments responded similarly to those of the Rhesus monkeys. These results and those of the calf/tail measurements of the squirrel monkeys suggest that they may utilize their tails as a compensatory reservoir during postural changes and therefore, may not be an appropriate animal model for man under some orthostatic test conditions.</p>","PeriodicalId":38125,"journal":{"name":"Journal of Electrical Bioimpedance","volume":"11 1","pages":"12-18"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/57/fe/joeb-11-012.PMC7531102.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10284371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Narrowband Array Processing Beamforming Technique for Electrical Impedance Tomography.","authors":"Venkatratnam Chitturi, Nagi Farrukh","doi":"10.2478/joeb-2019-0014","DOIUrl":"10.2478/joeb-2019-0014","url":null,"abstract":"<p><p>Electrical impedance tomography (EIT) has a large potential as a two dimensional imaging technique and is gaining attention among researchers across various fields of engineering. Beamforming techniques stem from the array signal processing field and is used for spatial filtering of array data to evaluate the location of objects. In this work the circular electrodes are treated as an array of sensors and beamforming technique is used to localize the object(s) in an electrical field. The conductivity distributions within a test tank is obtained by an EIT system in terms of electrode voltages. These voltages are then interpolated using elliptic partial differential equations. Finally, a narrowband beamformer detects the peak in the output response signal to localize the test object(s). Test results show that the beamforming technique can be used as a secondary method that may provide complementary information about accurate position of the test object(s) using an eight electrode EIT system. This method could possibly open new avenues for spatial EIT data filtering techniques with an understanding that the inverse problem is more likely considered here as a source localization algorithm instead as an image reconstruction algorithm.</p>","PeriodicalId":38125,"journal":{"name":"Journal of Electrical Bioimpedance","volume":"10 1","pages":"96-102"},"PeriodicalIF":0.0,"publicationDate":"2019-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/26/1b/joeb-10-096.PMC7851972.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25367482","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Non-linear Electrical Properties of Silver/silver Chloride Electrodes in Sodium Chloride Solution.","authors":"Oliver Pabst, Abbas Anwar, Adam Andrzej Nieweglowski, Christian Rolid Lindland, Habibur Rahman, Håvard Siljedal, Henning Thorkildsen, Ibrahim Camara, Kosar Nozari Mirarkolaei, Léa Massé, Magnus Solvi Hoen, Mohsin Noman Mustafa, Ole Johan Berg, Petter André Kristiansen, Ramzi Iguenad, Robin Alexander Torstensson Pedersen, Serwa Waisi, Trym Erik Nielsen","doi":"10.2478/joeb-2019-0017","DOIUrl":"10.2478/joeb-2019-0017","url":null,"abstract":"<p><p>An electrical measurement is non-linear when it is affected by the applied stimulus, i.e. when the measured phenomenon changes with amplitude. If pinched hysteresis loops can be observed in the voltage current representation, the underlying tissue can be classified as a memristor. Several biological memristors have been published, like human skin and apples. However, changes in the polarization impedance of electrodes may also cause pinched hysteresis loops. The question whether the reported biological memristors are real or whether the results just reflect changes in the polarization impedance arises. If the impedance of the measured object is close to or smaller than the polarization impedance of the used electrodes, the latter may dominate the measurement. In this study, we investigated the non-linear electrical properties of silver/silver chloride electrodes in a sodium chloride solution that has a similar concentration as human sweat and compared these to results from human skin. First of all, we found that silver/silver chloride electrodes in sodium chloride solution can be classified as memristors. However, the currents obtained from the sodium chloride solution are much higher than the currents recorded from human skin and there is a qualitative difference in the pinched hysteresis loops in both cases. We can conclude that the non-linear electrical measurements with silver/silver chloride on human skin are actually dominated by the skin and we can confirm that the human skin memristor really exists.</p>","PeriodicalId":38125,"journal":{"name":"Journal of Electrical Bioimpedance","volume":"10 1","pages":"113-123"},"PeriodicalIF":0.0,"publicationDate":"2019-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/6a/61/joeb-10-113.PMC7851973.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25368384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Circuit for Simultaneous Measurements of Skin Electrical Conductance, Susceptance, and Potential.","authors":"Ørjan G Martinsen, Håvard Kalvøy, Dindar S Bari, Christian Tronstad","doi":"10.2478/joeb-2019-0016","DOIUrl":"10.2478/joeb-2019-0016","url":null,"abstract":"<p><p>A circuit is presented that enables measurement of skin electrical conductance, susceptance, and potential simultaneously beneath the same monopolar electrode. Example measurements are shown to confirm the function of the circuit. The measurements are also in accordance with earlier findings that changes in skin conductance and potential do not always correspond and hence contain unique information.</p>","PeriodicalId":38125,"journal":{"name":"Journal of Electrical Bioimpedance","volume":"10 1","pages":"110-112"},"PeriodicalIF":0.0,"publicationDate":"2019-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/ed/c7/joeb-10-110.PMC7851977.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25367956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Machine Learning for Stem Cell Differentiation and Proliferation Classification on Electrical Impedance Spectroscopy.","authors":"André B Cunha, Jie Hou, Christin Schuelke","doi":"10.2478/joeb-2019-0018","DOIUrl":"10.2478/joeb-2019-0018","url":null,"abstract":"<p><p>Electrical impedance spectroscopy (EIS) measurements on cells is a proven method to assess stem cell proliferation and differentiation. Cell regenerative medicine (CRM) is an emerging field where the need to develop and deploy stem cell assessment techniques is paramount as experimental treatments reach pre-clinical and clinical stages. However, EIS measurements on cells is a method requiring extensive post-processing and analysis. As a contribution to address this concern, we developed three machine learning models for three different stem cell lines able to classify the measured data as proliferation or differentiation laying the stone for future studies on using machine learning to profile EIS measurements on stem cells spectra.</p>","PeriodicalId":38125,"journal":{"name":"Journal of Electrical Bioimpedance","volume":"10 1","pages":"124-132"},"PeriodicalIF":0.0,"publicationDate":"2019-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/88/94/joeb-10-124.PMC7851974.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25368385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Age-related Differences in the Morphology of the Impedance Cardiography Signal.","authors":"Christian Tronstad, Jan Olav Høgetveit, Ole Elvebakk, Håvard Kalvøy","doi":"10.2478/joeb-2019-0020","DOIUrl":"10.2478/joeb-2019-0020","url":null,"abstract":"<p><p>Impedance cardiography (ICG) is a non-invasive method of hemodynamic measurement, mostly known for estimation of stroke volume and cardiac output based on characteristic features of the signal. Compared with electrocardiography, the knowledge on the morphology of the ICG signal is scarce, especially with respect to age-dependent changes in ICG waveforms. Based on recordings from ten younger (20-29 years) and ten older (60-79) healthy human subjects after three different levels of physical activity, the typical interbeat ICG waveforms were derived based on ensemble averages. Comparison of these waveforms between the age groups indicates the following differences: a later initial upward deflection for the younger group, an additional hump in the waveform from many older subjects not presented in the younger group, and a more pronounced second wave in the younger group. The explanation for these differences is not clear, but may be related to arterial stiffness. Further studies are suggested to determine whether these morphological differences have clinical value.</p>","PeriodicalId":38125,"journal":{"name":"Journal of Electrical Bioimpedance","volume":"10 1","pages":"139-145"},"PeriodicalIF":0.0,"publicationDate":"2019-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/cd/36/joeb-10-139.PMC7851975.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25368387","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electrical Impedance Myography for Assessing Paraspinal Muscles of Patients with Low Back Pain.","authors":"Yun Wang, Laura Freedman, Martin Buck, Jose Bohorquez, Seward B Rutkove, John Keel","doi":"10.2478/joeb-2019-0015","DOIUrl":"10.2478/joeb-2019-0015","url":null,"abstract":"<p><p>The objective of this study was to determine the potential value of electrical impedance myography (EIM) for assessing lumbosacral paraspinal muscle (LPM) condition in lower back pain (LBP) patients. Standard methods for assessing the condition of LPMs, such as magnetic resonance imaging, are inconvenient and expensive. One tool that could be useful for this purpose is electrical impedance myography (EIM) a technique that can be performed rapidly at the bedside. After undergoing a screening history and examination, subjects were studied with the mView EIM device (Myolex, Inc, Boston). Bilateral LPMs were measured three times each and the two closest sets of measurements averaged on each side. Data analysis included non-parametric two-group comparisons between healthy subjects and back pain patients, receiver-operating curve analyses, and correlation analyses to age and body mass index. A total of 86 healthy individuals (median age (interquartile range) (IQR), 45.5 years (30.3-56.0 years), 42 men, 44 women) and 47 LBP (median age 51.0 year (39.5-57.5) years, 21 men, 26 women) were enrolled. Median EIM 100kHz phase was lower in the LBP patients (9.3°(IQR 8.4°-10.6°) versus 11.4°(IQR 9.4°-13.0°), p = 0.0007). Significantly increased normalized side-to-side differences were present for all three EIM variables (e.g., median 100 kHz phase 0.15 (IQR 0.07-0.31 in LBP patients versus 0.09 (IQR 0.04-0.17) in healthy individuals). A significant correlation between 100 kHz EIM phase and reactance was found with age (R_spearman=-0.46, P=0.0002 and R_spearman=-0.440, P=0.0003) but not for resistance. This study provides early evidence supporting that EIM has the potential to serve as a useful tool for evaluating the condition of LPMs.</p>","PeriodicalId":38125,"journal":{"name":"Journal of Electrical Bioimpedance","volume":"10 1","pages":"103-109"},"PeriodicalIF":0.0,"publicationDate":"2019-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/f2/ad/joeb-10-103.PMC7851978.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25367955","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of Body Composition in Oncologic Patients: Experimental Survey on the Role of Bioimpedentiometric Analysis.","authors":"Maria Alessandra Gammone,&nbsp;Cristiana Ficoneri,&nbsp;Nicolantonio D'Orazio","doi":"10.2478/joeb-2019-0013","DOIUrl":"https://doi.org/10.2478/joeb-2019-0013","url":null,"abstract":"<p><p>Overall survival of oncologic patients is strongly influenced by the incidence of malnutrition, with subsequent loss of muscle mass until sarcopenia. In this respect, the assessment of body composition has a pivotal role in order to manage the clinical consequences of muscle loss.</p><p><strong>Aim: </strong>This study focuses on the body composition assessment in oncologic patients, following a diet plan in order to detect and contrast neoplastic cachexia.</p><p><strong>Materials and method: </strong>35 oncologic patients were enrolled and divided into two groups: 24 responders (R) and 11 non-responders (NR). Anthropometric data were collected and body composition was assessed through bioimpedentiometry. All patients received an individualized normocaloric diet. Energetic content was assigned on the basis of individual basal metabolic rate estimated by BIA. All patients were revaluated by anthropometry and bioimpedentiometry 3 and 6 months thereafter.</p><p><strong>Results: </strong>Comparing the two male groups R and NR after 6 months, the former maintained almost the same confidence interval, unlike the latter whose interval increased, indicating a light worsening both of body composition and of clinical conditions. Furthermore, in the same male responder group, an improvement of the phase angle (PhA), a positive prognostic factor, was found, with an average weight loss between 2,6 - 3 kg of fat mass (FM). Besides, data show how the R female group maintained the confidence interval unlike the NR female group, whose confidence interval remarkably increased, therefore indicating an important alteration of body composition and subsequently a clinical conditions worsening. Finally, comparing the NR male group with the NR female group after 6 months, a remarkable worsening of body composition (marker of tissue decay and damage) could be noticed in the latter group.</p><p><strong>Conclusion: </strong>After 6 months, NR patients show worse results (both in the body composition and in the clinical conditions) compared to the responders, with particularly worse results in females, probably because of a genetically determined sex-related smaller muscle cells and inferior muscular strength. A multidimensional assessment of oncologic patient is necessary, with a special attention to nutritional evaluation and body composition monitoring, in order to avoid malnutrition and subsequent further clinical worsening.</p>","PeriodicalId":38125,"journal":{"name":"Journal of Electrical Bioimpedance","volume":"10 1","pages":"90-95"},"PeriodicalIF":0.0,"publicationDate":"2019-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/3c/b1/joeb-10-090.PMC7851971.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25367481","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}