Combined electrocardiogram and photoplethysmogram measurements as an indicator of objective sleepiness.

abstract：:Controversial data exist on acute and chronic effects of competitive sports on central hemodynamics and arterial stiffness. We investigated chronic as well as acute training effects in professional rowers. The trial was planned as a non-randomized, controlled pilot-study comparing athletes and controls. 13 German nati...

journal_title：Physiological measurement

authors： Franzen K,Reppel M,Köster J,Mortensen K

更新日期：2016-04-01 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：:In this phenomenological study we focus on dynamic measurements of volatile organic compounds (VOCs) in exhaled breath under exercise conditions. An experimental setup efficiently combining breath-by-breath analyses using proton transfer reaction mass spectrometry (PTR-MS) with data reflecting the behaviour of major h...

journal_title：Physiological measurement

authors： King J,Mochalski P,Kupferthaler A,Unterkofler K,Koc H,Filipiak W,Teschl S,Hinterhuber H,Amann A

更新日期：2010-09-01 00:00:00

abstract：:In this work, we describe a beat-by-beat method for assessing the clinical utility of pulsatile waveforms, primarily recorded from cardiovascular blood volume or pressure changes, concentrating on the photoplethysmogram (PPG). Physiological blood flow is nonstationary, with pulses changing in height, width and morphol...

journal_title：Physiological measurement

authors： Li Q,Clifford GD

更新日期：2012-09-01 00:00:00

abstract：:The ability to predict if an atrial fibrillation (AF) episode terminates spontaneously or not through non-invasive techniques is a challenging problem of great clinical interest. This fact could avoid useless therapeutic interventions and minimize the risks for the patient. The present work introduces a robust AF pred...

journal_title：Physiological measurement

authors： Alcaraz R,Rieta JJ

更新日期：2008-01-01 00:00:00

abstract：:In magnetic resonance electrical impedance tomography (MREIT) we inject currents through electrodes placed on the surface of a subject and try to reconstruct cross-sectional resistivity (or conductivity) images using internal magnetic flux density as well as boundary voltage measurements. In this paper we present a st...

journal_title：Physiological measurement

authors： Lee BI,Oh SH,Woo EJ,Lee SY,Cho MH,Kwon O,Seo JK,Baek WS

更新日期：2003-05-01 00:00:00

abstract：:The aim of this study was to establish whether analysis of the left ventricular pressure waveform provides indicative information about cardiac load and contractility and to develop an algorithm for computer-based assessment of changes in these variables. In eight healthy standard breed anaesthetized open-chest pigs, ...

journal_title：Physiological measurement

authors： Söderqvist E,Hultman J,Källner G,Nowak J,Brodin LA

更新日期：2006-12-01 00:00:00

abstract：:This review describes recent developments in microfabricated flow cytometers and related microfluidic devices that can detect, analyze, and sort cells or particles. The high-speed analytical capabilities of flow cytometry depend on the cooperative use of microfluidics, optics and electronics. Along with the improvemen...

journal_title：Physiological measurement

authors： Huh D,Gu W,Kamotani Y,Grotberg JB,Takayama S

更新日期：2005-06-01 00:00:00

abstract：:Pulmonary blood volume increase during systole was measured in patients by analysing chest images obtained during ECG gated radionuclide angiography examination. The difference in the total radiation counts between systole and diastole in regions of interest, which included the lungs and the left ventricle, was measur...

journal_title：Physiological measurement

authors： Nitzan M,Mahler Y,Schechter D,Yaffe S,Bocher M,Chisin R

更新日期：1994-11-01 00:00:00

abstract：:The main components responsible for the mechanical behavior of the arterial wall are collagen, elastin, and smooth muscle cells (SMCs) in the medial layer. We determined the structural and mechanical changes in porcine carotid arteries after administration of Triton® X-100, elastase, and collagenase using the inflatio...

journal_title：Physiological measurement

authors： Kochová P,Kuncová J,Svíglerová J,Cimrman R,Miklíková M,Liška V,Tonar Z

更新日期：2012-08-01 00:00:00

abstract：:A method was developed for simultaneously measuring plasma resistance, cell interior resistance and cell membrane capacitance of blood. A three-element circuit model for simulating the impedance of blood was evaluated by comparing measured and calculated impedance frequency curves and was found feasible. The values of...

journal_title：Physiological measurement

authors： Zhao TX,Jacobson B,Ribbe T

更新日期：1993-05-01 00:00:00

abstract：:Electrical impedance scanning (EIS) is a kind of potential bio-impedance measurement technology, especially aiding the diagnosis of breast cancer in women. By changing the frequency of the driving signal in turn while keeping the other conditions stable, multi-frequency measurement results on the object can be obtaine...

journal_title：Physiological measurement

authors： Liu R,Dong X,Fu F,You F,Shi X,Ji Z,Wang K

更新日期：2007-07-01 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：:This paper represents a reconstruction algorithm using a direct sensitivity matrix (DSM) approach for fast 3D image reconstruction in electrical impedance imaging. The boundary element method (BEM) is used in the construction of this matrix. The first images of a conductivity perturbation inside a sphere are reconstru...

journal_title：Physiological measurement

authors： Morucci JP,Granié M,Lei M,Chabert M,Marsili PM

更新日期：1995-08-01 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：:A gamma fit facilitates smoothing and extrapolation of distorted tracer-dilution curves in blood flow studies. Theoretically based empirical estimators were developed as simple alternatives to direct regression approaches from simulated gamma distributions with a wide range of shape asymmetry. Key curve features of pe...

journal_title：Physiological measurement

authors： Lopatatzidis A,Millard RK

更新日期：2001-11-01 00:00:00

abstract：:Plethysmographic measurement of airway resistance (R(aw)) has been determined by single-point analysis, usually at 50% of maximum inspiratory flow (MIF). Computer-assisted (best fit) analysis, however, allows R(aw) to be calculated by applying a regression line to any portion of the plethysmograph pressure-flow loop. ...

journal_title：Physiological measurement

authors： Thomas M,Greenough A,Blowes R,Rafferty GF,Calvert S,Marlow N,Peacock JL,Milner AD

更新日期：2002-05-01 00:00:00

abstract：:Although people spend a third of their day engaged in sedentary activities, research on heart activity during sitting is almost nonexistent because of the discomfort experienced when electrocardiogram (ECG) measurement electrodes are attached to the body. Accordingly, in this study, a system was developed to monitor h...

journal_title：Physiological measurement

authors： Lim E,Lee HK,Myoung HS,Lee KJ

更新日期：2015-03-01 00:00:00

abstract：:The effects of mechanical stimulation on hemodynamics, such as due to mechanotransduction in vascular endothelial cells, have been widely discussed recently. We previously proposed a resonance model in which the arterial system is treated as a pressure-transmitting system, and suggested that the application of externa...

journal_title：Physiological measurement

authors： Hsiu H,Jan MY,Wang WK,Wang YY

更新日期：2006-02-01 00:00:00

abstract：:The paper describes the development of an electrical impedance tomography (EIT) system for gynecologic research. The GIT (gynecological impedance tomography) system has 48 electrodes and is embedded on a small space (30 mm diameter and 20 mm height) inside of the vaginal probe. The system provides real-time (one shot ...

journal_title：Physiological measurement

authors： V A C,Y V G,A V K,S A S,T S T

更新日期：2012-05-01 00:00:00

abstract：:Tetrapolar linear arrays are commonly used in geophysics to explore the vertical distribution of resistivity values in a geological section of a specific point on the earth. This technique, known as vertical electric sounding (VES), uses different electrode configurations. For our experiments, we utilized its more pop...

journal_title：Physiological measurement

authors： Gonzalez CA,offniga O,Padilla LE

更新日期：1997-02-01 00:00:00

abstract：:The holy grail of neuroimaging would be to have an imaging system, which could image neuronal electrical activity over milliseconds. One way to do this would be by imaging the impedance changes associated with ion channels opening in neuronal membranes in the brain during activity. In principle, we could measure this ...

journal_title：Physiological measurement

authors： Ahadzi GM,Liston AD,Bayford RH,Holder DS

更新日期：2004-02-01 00:00:00

abstract：:Generalizability theory was used to investigate the score consistency of observed extracellular fluid/intracellular fluid (ECF/ICF) ratio measurements for both the global and leg-segmental bio-impedance spectroscopy methods. The test instrument used was a Xitron Hydra ECF/ICF Bio-Impedance Analyzer System, model 4200 ...

journal_title：Physiological measurement

authors： Turner AA,Lozano-Nieto A,Bouffard M

更新日期：2006-04-01 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：:This paper describes an open loop feedback intelligent system for neonatal intensive care management. The system provides a tool enabling the user to make the final decision to accept or reject the advice given. The system collects 18 parameters from the bedside monitor and ventilator using a Medical Information Bus (...

journal_title：Physiological measurement

authors： Belal SY,Taktak AF,Nevill A,Spencer A

更新日期：2005-08-01 00:00:00

abstract：:The effect of composition on the dielectric properties of hydrogels for biomedical applications is experimentally investigated. The hydrogels, containing hydroxyethylcellulose (HEC), are characterized by means of the impedance spectroscopy technique. The real and imaginary parts of the electrical impedance of the hydr...

journal_title：Physiological measurement

authors： Alexe-Ionescu AL,Barbero G,Freire FC,Merletti R

更新日期：2010-10-01 00:00:00

abstract：:Cardiac output (CO) monitoring is not only essential for critically ill patients in the hospital, but also for patients at home and those undergoing cardiopulmonary exercise testing. However, CO is difficult to monitor during daily activities and exercise. In this paper, we aim at developing a novel CO estimation meth...

journal_title：Physiological measurement

authors： Wang L,Poon CC,Zhang YT

更新日期：2010-05-01 00:00:00

abstract：:The recently-introduced technique of detrended fluctuation analysis (DFA) for heart-rate variability appears to yield improved prognostic power in cardiovascular disease through calculation of the fractal scaling exponent alpha. However, the physiological meaning of alpha remains unclear. In DFA, the signal is segment...

journal_title：Physiological measurement

authors： Willson K,Francis DP,Wensel R,Coats AJ,Parker KH

更新日期：2002-05-01 00:00:00

abstract：:Twenty-nine patients were monitored overnight for breathing distress patterns during postoperative analgesia. Nasal flow apnoea monitoring and pulse oximetry data were recorded at 50 Hz. Respiratory inductive plethysmography (RIP) tracked tidal volume (TV) thoracoabdominal motion, and supplemented the flow monitoring ...

journal_title：Physiological measurement

authors： Millard RK

更新日期：1999-05-01 00:00:00

abstract：OBJECTIVE:The ratio of the partial pressure of arterial oxygen to fraction of inspired oxygen is a key component of the sequential organ failure assessment score that operationally defines sepsis. But, it is calculated infrequently due to the need for the acquisition of an arterial blood gas. So, we sought to find an o...

journal_title：Physiological measurement

authors： Gadrey SM,Lau CE,Clay R,Rhodes GT,Lake DE,Moore CC,Voss JD,Moorman JR

更新日期：2019-12-03 00:00:00