Abstract:
:The electrocardiogram is a representative signal containing information about the condition of the heart. The shape and size of the P-QRS-T wave, the time intervals between its various peaks, etc may contain useful information about the nature of disease affecting the heart. However, the human observer cannot directly monitor these subtle details. Besides, since bio-signals are highly subjective, the symptoms may appear at random in the time scale. Therefore, the heart rate variability signal parameters, extracted and analyzed using computers, are highly useful in diagnostics. Analysis of heart rate variability (HRV) has become a popular noninvasive tool for assessing the activities of the autonomic nervous system. The HRV analysis is based on the concept that fast fluctuations may specifically reflect changes of sympathetic and vagal activity. It shows that the structure generating the signal is not simply linear, but also involves nonlinear contributions. These signals are essentially nonstationary; may contain indicators of current disease, or even warnings about impending diseases. The indicators may be present at all times or may occur at random in the time scale. However, to study and pinpoint abnormalities in voluminous data collected over several hours is strenuous and time consuming. This paper deals with the analysis of eight types of cardiac abnormalities and presents the ranges of linear and nonlinear parameters calculated for them with a confidence level of more than 90%.
journal_name
Physiol Measjournal_title
Physiological measurementauthors
Acharya U R,Kannathal N,Krishnan SMdoi
10.1088/0967-3334/25/5/005subject
Has Abstractpub_date
2004-10-01 00:00:00pages
1139-51issue
5eissn
0967-3334issn
1361-6579journal_volume
25pub_type
杂志文章abstract::Objective assessment of stroke-patients' ability to control arm movements is vital for evidence-based therapy and progress monitoring. This study compares three different indices to quantify the quality of wrist movement during a task involving tracking a target on a screen. Each method is assessed in terms of agreeme...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/28/8/011
更新日期:2007-08-01 00:00:00
abstract::Accelerometer wear location may influence physical activity estimates. This study investigates this relationship through the examination of activity patterns throughout the day. Participants from the aging research evaluating accelerometry (AREA) study (n men = 37, n women = 47, mean age (SD) = 78.9 (5.5) years)...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/37/10/1852
更新日期:2016-10-01 00:00:00
abstract::The transthoracic electrical impedance is an important defibrillation parameter, affecting the defibrillating current amplitude and energy, and therefore the defibrillation efficiency. A close relationship between transthoracic impedance and defibrillation success rate was observed. Pre-shock measurements (using low a...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/21/1/318
更新日期:2000-02-01 00:00:00
abstract::The specific heat capacity of tissue is a critical parameter for thermal therapies that act over a long period of time. It is also critical for thermoacoustic signal generation. We present ex vivo measurements of specific heat capacity performed by a dual-pin probe with tight temperature control of the specimen. One 3...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/32/11/N02
更新日期:2011-11-01 00:00:00
abstract:OBJECTIVE:The aim of this study was to monitor the physiological changes and cytotoxic effects of exogenous contrast agents during photoacoustic imaging (PAI) and photothermal therapy (PTT). In this paper, a low-power telemetric device for mouse vital signs monitoring was designed and demonstrated. APPROACH:The power ...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aba6a1
更新日期:2021-01-01 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
pub_type: 杂志文章
doi:10.1088/1361-6579/ab5154
更新日期:2019-12-03 00:00:00
abstract::We used finite element analysis to study the relationship between the intraventricular blood conductance and the right ventricular volume. Previous studies reported a quasi-linear dependence between these two quantities. We quantified the effects of the resistivities of the surrounding tissues (e.g. heart wall, lungs)...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/15/1/004
更新日期:1994-02-01 00:00:00
abstract::The relation between the right-side (RS) electrical impedance phase angle (PA) and segmental PA in five configurations at 50 kHz was analyzed in 23 peritoneal dialysis male patients before complete drainage of the abdominal cavity. The impedance vector (Z/H) components were standardized by the height H of the subjects...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/29/9/N01
更新日期:2008-09-01 00:00:00
abstract::In electrical impedance tomography (EIT) two-dimensional models continue to be applied despite their known inability to provide correct reconstruction. In this paper, a reconstruction algorithm that assumes a translationally invariant conductivity distribution is described. A more precise forward solver is obtained by...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/21/1/308
更新日期:2000-02-01 00:00:00
abstract::The outside of the skin of the forearm is typically 15 mV more negative than the inside. Stretching the skin causes a reduction in the magnitude of this skin potential V, which we observe as a motion artifact delta V. We seek to determine the origin of this motion artifact by successively stripping 12 layers of the sk...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/17/2/003
更新日期:1996-05-01 00:00:00
abstract::One unfortunate occurrence in experimental measurements with electrical impedance tomography is electrodes which become detached or poorly connected, such that the measured data cannot be used. This paper presents an automatic approach to detect such erroneous electrodes. It is based on the assumption that all valid m...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/26/2/017
更新日期:2005-04-01 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
pub_type: 杂志文章,评审
doi:10.1088/0967-3334/26/3/R02
更新日期:2005-06-01 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
pub_type: 杂志文章
doi:10.1088/0967-3334/33/8/1335
更新日期:2012-08-01 00:00:00
abstract::A finite difference model of the human thorax with 113,400 control volumes (nodes) based on ECG gated MRI images was used to evaluate the Sheffield DAS-01P EIT system. Sixteen simulated electrode positions equally spaced around the thorax model at approximately the fourth intercostals space level were selected. Pairs ...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/24/2/357
更新日期:2003-05-01 00:00:00
abstract:OBJECTIVE:Metal exposures have been linked with many adverse health outcomes affecting nearly every system in the body. Exposure to metals has been tracked primarily using blood. Blood metal concentrations have drawbacks as biomarkers stemming from the metals' short biologic half-lives, shipping and storage requirement...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aad947
更新日期:2018-08-31 00:00:00
abstract::Body temperature measurement is an important clinical parameter. The performance of a number of non-invasive thermometers was measured by comparing intra- and inter-operator variability (n = 100) and clinical accuracy (n = 61). Variability was elevated in febrile compared to normothermic subjects for axillary and oral...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/31/9/003
更新日期:2010-09-01 00:00:00
abstract::Nasal obstruction is common and may disturb well-being during daytime and sleep. Its objective assessment by standard methods requires patient cooperation and inconvenient instrumentation. Therefore, the purpose of this study was to develop a novel, unobtrusive technique for continuous monitoring of changes in nasal c...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/25/2/014
更新日期:2004-04-01 00:00:00
abstract::Previous studies demonstrate that it is possible to evaluate a heart graft rejection condition using a bioimpedance technique by means of an intracavitary catheter. We propose to use a less invasive technique consisting in the use of a transoesophageal catheter and two standard ECG electrodes on the thorax. The aim of...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/32/7/S10
更新日期:2011-07-01 00:00:00
abstract::A majority of geriatric patients experience difficulty in performing sit-to-stand (SiSt) transitions. A detailed assessment of SiSt ability is a prerequisite for successful rehabilitation. Body fixed sensors (BFSs) are increasingly used to assess functional performances. As to date there is no system which analyzes cl...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/33/11/1931
更新日期:2012-11-01 00:00:00
abstract::During anaesthesia awareness and nociception are serious complications that may further lead to haemodynamic instability. Specific monitoring of depth of hypnosis and depth of analgesia based on heart rate variability (HRV) analysis is eligible to improve patient safety and reduce efforts in post-operative care. Conse...
journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/33/2/207
更新日期:2012-02-01 00:00:00
abstract::A method is described that accounts for multichannel brain field data (EEG) epochs, after transformation into the frequency domain, by a single oscillating dipole source in terms of phase angles. The method produces a potential distribution for each frequency point ('FFT dipole approximation'). These maps can be subje...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/14/4a/004
更新日期:1993-11-01 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
pub_type: 杂志文章
doi:10.1088/0967-3334/26/4/019
更新日期:2005-08-01 00:00:00
abstract::This paper investigates the main characteristics of the magneto-hemodynamic (MHD) response for application as a biomarker of vascular blood flow. The induced surface potential changes of a volunteer exposed to a 3 T static B0 field of a magnetic resonance imaging (MRI) magnet were measured over time at multiple locati...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/33/2/117
更新日期:2012-02-01 00:00:00
abstract::The standard electrocardiogram (ECG) is the most common non-invasive way to study atrial fibrillation (AF). In this respect, previous works have shown that the surface lead V(1) reflects mainly the dominant atrial frequency (DAF) of the right atrium (RA), which has been widely used to study AF. In a similar way, AF or...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/32/1/007
更新日期:2011-01-01 00:00:00
abstract:OBJECTIVE:Sleep-stage scoring is important for sleep-quality evaluation and the diagnosis of related diseases. In this study, an automatic sleep-stage scoring method using photoplethysmographic (PPG) signals was proposed. APPROACH:To construct the classification model, we extracted 14 time-domain features, 17 frequenc...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/ab921d
更新日期:2020-06-30 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
pub_type: 杂志文章
doi:10.1088/0967-3334/33/9/1491
更新日期:2012-09-01 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
pub_type: 杂志文章
doi:10.1088/0967-3334/26/6/022
更新日期:2005-12-01 00:00:00
abstract::Measurements of blood volume pulse (BVP) and skin conductance are commonly used as indications of psychological arousal in affective computing and human-machine interfaces. To date, palmar surfaces remain the primary site for these measurements. Placement of sensors on palmar surfaces, however, is undesirable when rec...
journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/32/10/002
更新日期:2011-10-01 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
pub_type: 杂志文章
doi:10.1088/0967-3334/25/6/007
更新日期:2004-12-01 00:00:00
abstract::A photoplethysmographic (PPG) signal can provide very useful information about a subject's cardiovascular status. Motion artifacts (MAs), which usually deteriorate the waveform of a PPG signal, severely obstruct its applications in the clinical diagnosis and healthcare area. To reduce the MAs from a PPG signal, in the...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/36/10/2159
更新日期:2015-10-01 00:00:00