Journal of Electrical Bioimpedance最新文献

{"title":"Bioimpedance-based Authentication of Defrosted Versus Fresh Pork at the End of Refrigerated Shelf Life.","authors":"Daniel E Osen,&nbsp;Sisay Mebre Abie,&nbsp;Ørjan G Martinsen,&nbsp;Bjørg Egelandsdal,&nbsp;Daniel Münch","doi":"10.2478/joeb-2022-0017","DOIUrl":"https://doi.org/10.2478/joeb-2022-0017","url":null,"abstract":"<p><p>Correct food labeling is a legal requirement and helps consumers to make informed purchasing choices. Mislabeling defrosted meat as fresh is illegal in the EU. However, there are no standardized technologies to authenticate fresh versus defrosted meat. We address this by testing if bioimpedance-based measurements can separate defrosted meat from refrigerated-only meat at the end of shelf life, i.e., when also fresh meat shows deterioration. Pork sirloin samples from 20 pigs were first tested at 12 days postmortem ('fresh group'). This time point was chosen to represent a typical use-by date for refrigerated storage of fresh pork. Then, all samples were transferred to a -24°C freezer for 3 days and thawed for 2 days before final testing ('frozen-thawed group'). Bioimpedance analyses (BIA) were done in a frequency range of [10²-10⁶ Hz]. Weight, pH and electrode positioning were assessed to test for potential confounding effects. Statistics for treatment dependent differences were based on the established P_y parameter and phase angle, which were extracted from the BI spectra. We found that using bioimpedance testing with tetrapolar electrodes, P_y and phase angle allowed almost complete separation of fresh and previously frozen samples. However, within the whole sample population, there was some overlap between the spectra of fresh and frozen samples. Yet, based on P_y, only one fresh sample (5% of N_total=20) fell in the lowest P_y class with all the frozen samples. We used a multifactorial design that allowed to test the effects of potential confounding factors, such as electrode positioning and meat quality parameters. We found a relatively low explained variance for the P_y parameter, indicating that confounding effects from other factors or quality defects in fresh pork may affect the detection capacity of bioimpedance-based authentication of fresh pork. Our data, therefore, suggest that reliable fresh-label authentication with bioimpedance testing should be based on testing a small number of samples to represent a specific lot of pork that is to be inspected.</p>","PeriodicalId":38125,"journal":{"name":"Journal of Electrical Bioimpedance","volume":"13 1","pages":"125-131"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9837875/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10677638","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":"Algorithms for Reconstruction of Impedance Spectra from Non-uniformly Sampled Step Responses.","authors":"Y Zaikou,&nbsp;C Gansauge,&nbsp;D Echtermeyer,&nbsp;U Pliquett","doi":"10.2478/joeb-2022-0020","DOIUrl":"https://doi.org/10.2478/joeb-2022-0020","url":null,"abstract":"<p><p>Fast and reliable bioimpedimetric measurements are of growing importance in many practical applications. In this work we used a measurement method in time domain by processing the step response of the biological system under test. In order to decrease the data volume and computation time while retaining all relevant information the step response is sampled non-uniformly. Consequently, fast Fourier transform cannot be directly used for spectrum calculation and non-conventional data processing algorithms for transforming measured data into the frequency domain are required. In this paper we present corresponding computational methods. They are split into two groups. The first group is oriented on calculating the local approximation of the measured step response with a set of proper functions and calculating its spectrum via analytical Fourier transform, thus yielding a relatively versatile approach for estimating the impedance spectrum. In this case, the choice of approximating functions that suit known a priori properties of the measured signals are of great importance. A second group of methods relies on the evaluation of important signal parameters directly in the time domain. In this case we use a priori information about the measurement object in the form of an underlying model. After that the model is fitted to the measured data and thus, parameter values are extracted. Practical aspects, advantages and drawbacks of all considered data processing steps are revealed when applying them to the measurements made with real biological objects.</p>","PeriodicalId":38125,"journal":{"name":"Journal of Electrical Bioimpedance","volume":"13 1","pages":"143-149"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9837874/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9178526","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":"Monitoring the Skin Biophysical Parameters Among Coronavirus Patients for Three Days in a Row: a Preliminary Study","authors":"J. M. Salih, D. S. Bari, Haval Y. Yacoob Aldosky","doi":"10.2478/joeb-2022-0004","DOIUrl":"https://doi.org/10.2478/joeb-2022-0004","url":null,"abstract":"Abstract The coronavirus epidemic 2019 is spreading all over the world now. Several parameters are used to monitor the status of hospitalized patients; however, monitoring variations in biophysical properties of the skin has not been investigated yet. In this preliminary study, we seek to monitor skin biophysical parameters among coronavirus patients for three days in a row. Skin moisture, pH, sebum, and temperature during the three days were monitored in 30 coronavirus patients by using non-invasive portable instruments. Skin biophysical parameters were increased on the third day of monitoring compared to the first one. In addition, the increase in both skin moisture and temperature were statistically significant. According to the results of this preliminary study, skin biophysical parameters changed (increased) during the specified period in which the patients were monitored. However, changes in skin sebum content and pH were not significant. These skin parameters need to be further investigated until we know their indication ability for the health condition of coronavirus patients in clinical applications.","PeriodicalId":38125,"journal":{"name":"Journal of Electrical Bioimpedance","volume":"13 1","pages":"21 - 24"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46400335","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Intravascular, Interstitial and Intracellular Volume Changes During Short Term Deep Tissue Massage of the Calf: A Case Study.","authors":"Leslie D Montgomery,&nbsp;Rowena Galang,&nbsp;Richard W Montgomery","doi":"10.2478/joeb-2022-0011","DOIUrl":"https://doi.org/10.2478/joeb-2022-0011","url":null,"abstract":"<p><p>The following case study demonstrates that the effectiveness of Deep Tissue Massage (DTM) can be monitored in real time with bioimpedance. DTM techniques are used as a medical treatment to help reduce swelling of the calves of congestive heart failure patients. Bioimpedance monitoring shows immediately how fluid is redistributed within the intravascular, interstitial and intracellular fluid compartments, and how long the redistribution lasts. Bioimpedance spectroscopy, as used in this study, is a non-invasive procedure that can be used to monitor compartment fluid volumes and changes during many fluid management procedures.</p>","PeriodicalId":38125,"journal":{"name":"Journal of Electrical Bioimpedance","volume":"13 1","pages":"73-77"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9709818/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10433283","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 Plethysmography Versus Tonometry To Measure the Pulse Wave Velocity in Peripheral Arteries in Young Healthy Volunteers: a Pilot Study.","authors":"A I P Wiegerinck,&nbsp;A Thomsen,&nbsp;J Hisdal,&nbsp;H Kalvøy,&nbsp;C Tronstad","doi":"10.2478/joeb-2021-0020","DOIUrl":"https://doi.org/10.2478/joeb-2021-0020","url":null,"abstract":"<p><p>The leading cause of health loss and deaths worldwide are cardiovascular diseases. A predictor of cardiovascular diseases and events is the arterial stiffness. The pulse wave velocity (PWV) can be used to estimate arterial stiffness non-invasively. The tonometer is considered as the gold standard for measuring PWV. This approach requires manual probe fixation above the artery and depends on the skills of the operator. Electrical impedance plethysmography (IPG) is an interesting alternative using skin surface sensing electrodes, that is miniaturizable, cost-effective and allows measurement of deeper arteries. The aim of this pilot study was to explore if IPG can be a suitable technique to measure pulse wave velocity in legs as an alternative for the tonometer technique. The PWV was estimated by differences in the ECG-gated pulse arrival times (PAT) at the <i>a. femoralis, a. popliteal, a. tibialis dorsalis</i> and <i>a. dorsalis pedis</i> in nine healthy young adults using IPG and the SphygmoCor tonometer as a reference. The estimated PWV results from bioimpedance and the tonometer were fairly in agreement, and the beat-to-beat variability in PAT was similar. This pilot study indicates that the use of IPG may be a good alternative for estimating PWV in the legs.</p>","PeriodicalId":38125,"journal":{"name":"Journal of Electrical Bioimpedance","volume":"12 1","pages":"169-177"},"PeriodicalIF":0.0,"publicationDate":"2021-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8776312/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39759468","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":"Electric Cell-substrate Impedance Sensing in Biocompatibility Research.","authors":"Andrzej Kociubiński","doi":"10.2478/joeb-2021-0019","DOIUrl":"https://doi.org/10.2478/joeb-2021-0019","url":null,"abstract":"<p><p>In this paper, the possibility of using cell culture impedance measurements to assess the biocompatibility of a material in contact with cells was analyzed. For this purpose, the Electric Cell-substrate Impedance Sensing (ECIS) method and a commercial measuring device were used. The test substrates with thin-film electrodes made of various metals were prepared using the magnetron sputtering method. The choice of metals was dictated by their varying degrees of biocompatibility. Cultures of mouse fibroblasts were cultured on the prepared substrates. The experiment showed that the complete cycle of culture from attachment and reproduction to apoptosis occurred. The results obtained indicate that it is possible to use the ECIS method to study the influence of metal on cell culture activity.</p>","PeriodicalId":38125,"journal":{"name":"Journal of Electrical Bioimpedance","volume":"12 1","pages":"163-168"},"PeriodicalIF":0.0,"publicationDate":"2021-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8776311/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39744487","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":"Classification of Emotions Based on Electrodermal Activity and Transfer Learning - a Pilot Study.","authors":"Fredrik A Jacobsen,&nbsp;Ellen W Hafli,&nbsp;Christian Tronstad,&nbsp;Ørjan G Martinsen","doi":"10.2478/joeb-2021-0021","DOIUrl":"https://doi.org/10.2478/joeb-2021-0021","url":null,"abstract":"<p><p>This paper describes the development, execution and results of an experiment assessing emotions with electrodermal response measurements and machine learning. With ten participants, the study was carried out by eliciting emotions through film clips. The data was gathered with the Sudologger 3 and processed with continuous wavelet transformation. A machine learning algorithm was used to classify the data with the use of transfer learning and random forest classification. The results showed that the experiment lays a foundation for further exploration in the field. The addition of augmented data strengthened the classification and proved that more data would benefit the machine learning algorithm. The pilot study brought to light several areas to help with the expansion of the study for larger scale assessment of emotions with electrodermal response measurements and machine learning for the benefit of fields like psychology.</p>","PeriodicalId":38125,"journal":{"name":"Journal of Electrical Bioimpedance","volume":"12 1","pages":"178-183"},"PeriodicalIF":0.0,"publicationDate":"2021-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8776313/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39759469","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":"Stochastic Bioimpedance-Based Channel Model of The Human Body for Galvanic Coupling.","authors":"Aaron Roopnarine, Sean A Rocke","doi":"10.2478/joeb-2021-0014","DOIUrl":"10.2478/joeb-2021-0014","url":null,"abstract":"<p><p>Human body communication (HBC) uses the human body as the channel to transfer data. Extensive work has been done to characterize the human body channel for different HBC techniques and scenarios. However, statistical channel bioimpedance characterisation of human body channels, particularly under dynamic conditions, remains relatively understudied. This paper develops a stochastic fading bioimpedance model for the human body channel using Monte Carlo simulations. Differential body segments were modelled as 2-port networks using ABCD parameters which are functions of bioimpedance based body parameters modelled as random variables. The channel was then modelled as the cascade of these random 2-port networks for different combinations of probability distribution functions (PDFs) assumed for the bioimpedance-based body parameters. The resultant distribution of the cascaded body segments varied for the different assumed bioimpedance based body parameter distributions and differential body segment sizes. However, considering the distribution names that demonstrated a best fit (in the top 3 PDF rankings) with highest frequency under the varying conditions, this paper recommends the distribution names: Generalized Pareto for phase distributions and Log-normal for magnitude distributions for each element in the overall cascaded random variable ABCD matrix.</p>","PeriodicalId":38125,"journal":{"name":"Journal of Electrical Bioimpedance","volume":"12 1","pages":"117-124"},"PeriodicalIF":0.0,"publicationDate":"2021-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8713383/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39729218","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":"Thoracic, Peripheral, and Cerebral Volume, Circulatory and Pressure Responses To PEEP During Simulated Hemorrhage in a Pig Model: a Case Study.","authors":"Leslie D Montgomery,&nbsp;Richard W Montgomery,&nbsp;Michael Bodo,&nbsp;Richard T Mahon,&nbsp;Frederick J Pearce","doi":"10.2478/joeb-2021-0013","DOIUrl":"10.2478/joeb-2021-0013","url":null,"abstract":"<p><p>Positive end-expiratory pressure (PEEP) is a respiratory/ventilation procedure that is used to maintain or improve breathing in clinical and experimental cases that exhibit impaired lung function. Body fluid shift movement is not monitored during PEEP application in intensive care units (ICU), which would be interesting specifically in hypotensive patients. Brain injured and hypotensive patients are known to have compromised cerebral blood flow (CBF) autoregulation (AR) but currently, there is no non-invasive way to assess the risk of implementing a hypotensive resuscitation strategy and PEEP use in these patients. The advantage of electrical bioimpedance measurement is that it is noninvasive, continuous, and convenient. Since it has good time resolution, it is ideal for monitoring in intensive care units (ICU). The basis of its future use is to establish physiological correlates. In this study, we demonstrate the use of electrical bioimpedance measurement during bleeding and the use of PEEP in pig measurement. In an anesthetized pig, we performed multimodal recording on the torso and head involving electrical bioimpedance spectroscopy (EIS), fixed frequency impedance plethysmography (IPG), and bipolar (rheoencephalography - REG) measurements and processed data offline. Challenges (n=16) were PEEP, bleeding, change of SAP, and CO₂ inhalation. The total measurement time was 4.12 hours. Systemic circulatory results: Bleeding caused a continuous decrease of SAP, cardiac output (CO), and increase of heart rate, temperature, shock index (SI), vegetative - Kerdo index (KI). Pulse pressure (PP) decreased only after second bleeding which coincided with loss of CBF AR. Pulmonary arterial pressure (PAP) increased during PEEP challenges as a function of time and bleeding. EIS/IPG results: Body fluid shift change was characterized by EIS-related variables. Electrical Impedance Spectroscopy was used to quantify the intravascular, interstitial, and intracellular volume changes during the application of PEEP and simulated hemorrhage. The intravascular fluid compartment was the primary source of blood during hemorrhage. PEEP produced a large fluid shift out of the intravascular compartment during the first bleeding period and continued to lose more blood following the second and third bleeding. Fixed frequency IPG was used to quantify the circulatory responses of the calf during PEEP and simulated hemorrhage. PEEP reduced the arterial blood flow into the calf and venous outflow from the calf. Head results: CBF AR was evaluated as a function of SAP change. Before bleeding, and after moderate bleeding, intracranial pressure (ICP), REG, and carotid flow pulse amplitudes (CFa) increased. This change reflected vasodilatation and active CBF AR. After additional hemorrhaging during PEEP, SAP, ICP, REG, CFa signal amplitudes decreased, indicating passive CBF AR. 1) The indicators of active AR status by modalities was the following: REG (n=9, 56 %), CFa ","PeriodicalId":38125,"journal":{"name":"Journal of Electrical Bioimpedance","volume":"12 1","pages":"103-116"},"PeriodicalIF":0.0,"publicationDate":"2021-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8713386/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39729217","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":"Improved Estimation of Left Ventricular Volume from Electric Field Modeling.","authors":"Leonie Korn,&nbsp;Stephan Dahlmanns,&nbsp;Steffen Leonhardt,&nbsp;Marian Walter","doi":"10.2478/joeb-2021-0015","DOIUrl":"https://doi.org/10.2478/joeb-2021-0015","url":null,"abstract":"<p><p>Volume measurement is beneficial in left ventricular assist device (LVAD) therapy to quantify patient demand. In principle, an LVAD could provide a platform that allows bioimpedance measurements inside the ventricle without requiring additional implants. Conductance measured by the LVAD can then be used to estimate the ventricular radius, which can be applied to calculate ventricular volume. However, established methods that estimate radius from conductance require elaborate individual calibration or show low accuracy. This study presents two analytical calculation methods to estimate left ventricular radius from conductance using electric field theory. These methods build on the established method of Wei, now considering the dielectric properties of muscle and background tissue, the refraction of the electric field at the blood-muscle boundary, and the changes of the electric field caused by the measurements. The methods are validated in five glass containers of different radius. Additional bioimpedance measurements are performed in in-vitro models that replicate the left ventricle's shape and conductive properties. The proposed analytical calculation methods estimate the radii of the containers and the in-vitro models with higher accuracy and precision than Wei's method. The lead method performs excellently in glass cylinders over a wide range of radii (bias: 1.66%-2.48%, limits of agreement < 16.33%) without calibration to specific geometries.</p>","PeriodicalId":38125,"journal":{"name":"Journal of Electrical Bioimpedance","volume":"12 1","pages":"125-134"},"PeriodicalIF":0.0,"publicationDate":"2021-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8713389/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39729219","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}