Video rate electrical impedance tomography of vascular changes: preclinical development.

abstract：OBJECTIVE:Eye-tracking devices have become widely used as clinical assessment tools in a variety of applied-scientific fields to measure saccadic eye movements. With the emergence of multiple static and dynamic devices, the concurrent need for algorithm development and validation is paramount. APPROACH:This review ass...

journal_title：Physiological measurement

authors： Stuart S,Hickey A,Vitorio R,Welman K,Foo S,Keen D,Godfrey A

更新日期：2019-02-26 00:00:00

abstract：OBJECTIVE:To quantify the presence of cardiorespiratory interaction in a group of 41 healthy subjects performing a subset of the Ewing test battery. APPROACH:We measure the empirical distribution of the cardiorespiratory coupling time (RI), defined as the time from inspiration onset to R peaks in the ECG. The study pr...

journal_title：Physiological measurement

authors： Sobiech T,Buchner T,Krzesiński P,Gielerak G

更新日期：2017-11-30 00:00:00

abstract：:Epidemiological studies have associated the negative effects of sedentary time and sedentary patterns on health indices. However, these studies have used methodologies that do not directly measure the sedentary state. Recent technological developments in the area of motion sensors have incorporated inclinometers, whic...

journal_title：Physiological measurement

authors： Dowd KP,Harrington DM,Bourke AK,Nelson J,Donnelly AE

更新日期：2012-11-01 00:00:00

abstract：:This paper discusses some important issues for the design of electrical impedance measurement systems intended for body fluid shift monitoring, in particular during dialysis treatments. We have studied two common signal generation systems: digital synthesis and carrier recovery. We have found that in prolonged measure...

journal_title：Physiological measurement

authors： Lozano A,Rosell J,Pallás-Areny R

更新日期：1995-11-01 00:00:00

abstract：:Imaging photoplethysmography is a relatively new technique for extracting biometric information from video images of faces. This is useful in non-invasive monitoring of patients including neonates or the aged, with respect to sudden infant death syndrome, sleep apnoea, pulmonary disease, physical or mental stress and ...

journal_title：Physiological measurement

authors： Mannapperuma K,Holton BD,Lesniewski PJ,Thomas JC

更新日期：2015-01-01 00:00:00

abstract：:We investigated the utility of ICA for evaluation of fetal rhythm in five uncomplicated twin pregnancies and in five twin pregnancies complicated by fetal arrhythmia. Using objective and subjective criteria, we sought to determine how the signal-to-noise ratio, signal fidelity and interference rejection are affected w...

journal_title：Physiological measurement

authors： Mensah-Brown NA,Lutter WJ,Comani S,Strasburger JF,Wakai RT

更新日期：2011-01-01 00:00:00

abstract：:The purpose of this study was to examine the performance of dual-energy computed tomography (DECT) for the quantification of liver fat content (LFC). We prepared two phantoms: homogenized mixtures of porcine liver and fat and homogeneous mixtures of liver- and fat-equivalent solutions. Tubes containing mixtures with k...

journal_title：Physiological measurement

authors： Li JH,Tsai CY,Huang HM

更新日期：2014-04-01 00:00:00

abstract：:EPR oximetry is a promising, relatively non-invasive method for monitoring the partial pressure of oxygen in tissue (PtO2) that has proved useful in following changes under various physiologic and pathophysiologic conditions. Optimal utilization of the method will be facilitated by systematic comparisons with other av...

journal_title：Physiological measurement

authors： O'Hara JA,Khan N,Hou H,Wilmo CM,Demidenko E,Dunn JF,Swartz HM

更新日期：2004-12-01 00:00:00

abstract：:In recent AASM practice, parameter actimetry is cited to measure total sleep time in obstructive sleep apnoea patients, when polysomnography is not available. An actigraph was therefore compared to polysomnographic data in 28 subjects with known sleep disordered breathing. Total sleep time (TST), sleep period time (SP...

journal_title：Physiological measurement

authors： Dick R,Penzel T,Fietze I,Partinen M,Hein H,Schulz J

更新日期：2010-12-01 00:00:00

abstract：:In this study, we designed and tested a new algorithm, which we call the 'restricted parabola', to identify the optimum atrioventricular (AV) delay in patients with biventricular pacemakers. This algorithm automatically restricts the hemodynamic data used for curve fitting to the parabolic zone in order to avoid inadv...

journal_title：Physiological measurement

authors： Dehbi HM,Jones S,Sohaib SM,Finegold JA,Siggers JH,Stegemann B,Whinnett ZI,Francis DP

更新日期：2015-09-01 00:00:00

abstract：:Previous studies have used isokinetic dynamometry to assess joint torques and angles during passive extension of the knee, often without reporting upon methodological errors and reliability outcomes. In addition, the reliability of the techniques used to measure passive knee extension torque-angle and the extent to wh...

journal_title：Physiological measurement

authors： Freitas SR,Vaz JR,Bruno PM,Valamatos MJ,Mil-Homens P

更新日期：2013-11-01 00:00:00

abstract：:Current methods for analysing foetal heart rate (FHR) patterns have yet to meet their full potential in the recognition of hypoxia in the foetus. Following the recent suggestion that fractal analysis can be applied to FHR recordings, the current paper describes a method for distinguishing two simultaneous fractal dime...

journal_title：Physiological measurement

authors： Gough NA

更新日期：1993-08-01 00:00:00

abstract：:The goal of the present study was to develop and evaluate a new method for the prediction of unexplained syncope occurrences. Diagnosis of syncope is currently based on the reproduction of symptoms in combination with hypotension and bradycardia induced by a 45 min 60-70 degrees head-upright tilt test (HUTT). The main...

journal_title：Physiological measurement

authors： Schang D,Feuilloy M,Plantier G,Fortrat JO,Nicolas P

更新日期：2007-02-01 00:00:00

abstract：:Dual-energy x-ray absorptiometry (DXA) is a precise, widely used method for measuring bone mineral density (BMD), usually of the lumbar spine and femoral neck. Recent developments, such as a lower x-ray tube current and pixel by pixel analysis, enable smaller bones and thinner tissues volumes, as in the hand, to be me...

journal_title：Physiological measurement

authors： Steel SA,Swann P,Langley G,Langton CM

更新日期：1997-08-01 00:00:00

abstract：BACKGROUND:Uterine activity monitoring is an essential part of managing the progress of pregnancy and labor. Although intrauterine pressure (IUP) is the only reliable method of estimating uterine mechanical activity, it is highly invasive. Since there is a direct relationship between the electrical and mechanical activ...

journal_title：Physiological measurement

authors： Benalcazar-Parra C,Garcia-Casado J,Ye-Lin Y,Alberola-Rubio J,Lopez Á,Perales-Marin A,Prats-Boluda G

更新日期：2019-09-03 00:00:00

abstract：:This paper presents the design, construction and testing of a device to measure pressure-volume loops in the left ventricle of conscious, ambulatory rats. Pressure is measured with a standard sensor, but volume is derived from data collected from a tetrapolar electrode catheter using a novel admittance technique. Ther...

journal_title：Physiological measurement

authors： Raghavan K,Feldman MD,Porterfield JE,Larson ER,Jenkins JT,Escobedo D,Pearce JA,Valvano JW

更新日期：2011-06-01 00:00:00

abstract：OBJECTIVE:Bioimpedance has been used to investigate changes in electrical parameters during ischemia in various tissues. The small intestine is a multi-layered structure, with several distinct tissue types, and ischemia related changes occur at different times in the different intestinal layers. When investigating how ...

journal_title：Physiological measurement

authors： Strand-Amundsen RJ,Reims HM,Tronstad C,Kalvøy H,Martinsen ØG,Høgetveit JO,Ruud TE,Tønnessen TI

更新日期：2017-05-01 00:00:00

abstract：:A study of the concentrations of the common breath metabolites ammonia, acetone, isoprene, ethanol and acetaldehyde in the breath of five subjects over a period of 30 days has been carried out. Breath samples were taken and analysed in the early morning on arrival at the laboratory. The real time analyses of three con...

journal_title：Physiological measurement

authors： Diskin AM,Spanel P,Smith D

更新日期：2003-02-01 00:00:00

abstract：:An analytic solution of the potential distribution on a 2D homogeneous disk for electrical impedance tomography under the complete electrode model is expressed via an infinite system of linear equations. For the shunt electrode model with two electrodes, our solution coincides with the previously derived solution expr...

journal_title：Physiological measurement

authors： Demidenko E

更新日期：2011-09-01 00:00:00

abstract：OBJECTIVE:Electrical impedance tomography (EIT) is a functional imaging technique in which cross-sectional images of structures are reconstructed based on boundary trans-impedance measurements. Continuous functional thorax monitoring using EIT has been extensively researched. Increasing the number of electrodes, number...

journal_title：Physiological measurement

authors： Shiraz A,Khodadad D,Nordebo S,Yerworth R,Frerichs I,van Kaam A,Kallio M,Papadouri T,Bayford R,Demosthenous A

更新日期：2019-04-03 00:00:00

abstract：:Electrical impedance tomography (EIT) image reconstruction is an ill-posed problem requiring maximum measurement precision. Recent EIT systems claim 60 to 80 dB precision. Achieving higher values is hard in practice since measurements must be performed at relatively high frequency, on a living subject, while using com...

journal_title：Physiological measurement

authors： Hartinger AE,Gagnon H,Guardo R

更新日期：2006-05-01 00:00:00

abstract：:Cooperative sensors is a novel measurement architecture that allows the acquiring of biopotential signals on patients in a comfortable and easy-to-integrate manner. The novel sensors are defined as cooperative in the sense that at least two of them work in concert to measure a target physiological signal, such as a mu...

journal_title：Physiological measurement

authors： Rapin M,Proença M,Braun F,Meier C,Solà J,Ferrario D,Grossenbacher O,Porchet JA,Chételat O

更新日期：2015-04-01 00:00:00

abstract：UNLABELLED:The study created an 'ex vivo' model to test different algorithms for measurements of mucosal haemoglobin saturation with visible light spectrophotometry (VLS). The model allowed comparison between algorithms, but it also allowed comparison with co-oximetry using a 'gold standard' method. This has not been d...

journal_title：Physiological measurement

authors： Gade J,Greisen G

更新日期：2016-09-01 00:00:00

abstract：:Stroke is a major cause of disability within the western world. About 20% of strokes are a consequence of atheromatous narrowing of the origin of the internal carotid artery. Carotid endarterectomy has been shown to be an effective treatment for those with symptomatic and severe stenosis, provided the risk of death an...

journal_title：Physiological measurement

authors： Crossman J,Banister K,Bythell V,Bullock R,Chambers I,Mendelow AD

更新日期：2003-05-01 00:00:00

abstract：:The changes in haemoglobin oxygenation (SO2) occurring in the tuberculin reaction in human skin were measured using macro- and micro-lightguide spectrophotometry and the results compared. A significant difference was found between the measurements from the respective instruments, demonstrating that the micro-lightguid...

journal_title：Physiological measurement

authors： Newton DJ,Harrison DK,Delaney CJ,Beck JS,McCollum PT

更新日期：1994-05-01 00:00:00

abstract：:Electroneurograms (ENGs) from the vagus nerve (VN), the splanchnic nerve (SN) and the pancreatic nerve (PN) innervating the pancreas of a dog, were recorded with chronically implanted 33-electrode spiral cuffs (cuff) before and after the pancreas were stimulated with intravenously (i.v.) administered glucose. In the c...

journal_title：Physiological measurement

authors： Rozman J,Zorko B,Bunc M,Mikac U,Tegou E

更新日期：2002-11-01 00:00:00

abstract：:The outflow conductance (C(out)) of the cerebrospinal fluid (CSF) system is a parameter considered to be predictive in selection for hydrocephalus surgery. C(out) can be determined through an infusion test. A new apparatus for performing infusion tests in a standardized and automated way was developed. The objective w...

journal_title：Physiological measurement

authors： Andersson N,Malm J,Bäcklund T,Eklund A

更新日期：2005-12-01 00:00:00

abstract：:The point spread function (PSF) is the most widely used tool for quantifying the spatial resolution of imaging systems. However, prerequisites for the proper use of this tool are linearity and space invariance. Because EIT is non-linear it is only possible to compare different reconstruction algorithms using a standar...

journal_title：Physiological measurement

authors： Ider YZ,Eyüboğlu BM,Kuzuoğlu M,Leblebïcïoğlu K,Baysal U,Cağlar BK,Bïrgül O

更新日期：1995-08-01 00:00:00

abstract：:Non-contact heart and lung activity monitoring would be a desirable supplement to conventional monitoring techniques. Based on the potential of non-contact magnetic induction measurements, requirements for an adequate monitoring system were estimated. This formed the basis for the development of the presented extendab...

journal_title：Physiological measurement

authors： Steffen M,Heimann K,Bernstein N,Leonhardt S

更新日期：2008-06-01 00:00:00

abstract：:The purpose of this study was to examine the validity and reliability of estimated parameters of the work-time relationship during cross-country ski ergometry using the traditional multi-trial critical power (CP) test and a 3 min 'all-out' test (3MT). Fourteen recreationally active male participants (mean ± SD; age: 2...

journal_title：Physiological measurement

authors： Fukuda DH,Hetrick RP,Kendall KL,Smith-Ryan AE,Jackson ME,Stout JR

更新日期：2014-01-01 00:00:00