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Devonshire I M - - 2009
This report describes a simple, non-invasive electronic device that employs a compact accelerometer integrated circuit to transduce movements in the chest wall of an anaesthetized animal into an analogue signal that can be used to calculate the rate and relative depth of respiration. The device requires amplification by signal processing ...
Ramchandra R - - 2009
Sympathetic nerve activity (SNA) consists of discharges that vary in amplitude and frequency, reflecting the level of recruitment of nerve fibers and the rhythmic generation and entrainment of activity by the central nervous system. It is unknown whether selective changes in these amplitude and frequency components account for organ-specific changes ...
Smit Dasten - - 2009
BACKGROUND: The effects of different breath-holding positions during electrocardiographic (ECG) recording on the QRS complex are unknown. METHODS: In 73 subjects, ECG recordings were made in 3 different breath-holding positions: normal expiration (rest), maximum inspiration, and maximum expiration. QRS wave excursions and changes in the frontal electrical heart axis were ...
Chang Catie C Department of Electrical Engineering, Stanford University, Stanford, CA 94305-5488, USA. - - 2009
A significant component of BOLD fMRI physiological noise is caused by variations in the depth and rate of respiration. It has previously been demonstrated that a breath-to-breath metric of respiratory variation (respiratory volume per time; RVT), computed from pneumatic belt measurements of chest expansion, has a strong linear relationship with ...
Héroux M E - - 2009
OBJECTIVES: Determine the effect of inertial loading on the strength of motor unit entrainment and the synergistic/competitive interaction between central and mechanical reflex tremor components in subjects with essential tremor (ET). METHODS: Twenty-three subjects with ET and 22 controls held their hand in an outstretched position while supporting sub-maximal loads ...
Chouchou Florian - - 2009
It was already established that exposure to hyperbaric conditions induces vagal-depended bradycardia but field study on autonomic nervous system (ANS) activity during self-contained underwater breathing apparatus (SCUBA) diving is lacking. The aim of the present study was to evaluate ANS modifications during real recreational SCUBA diving using heart rate variability ...
Olafsson Ragnar R Biomedical Engineering Department, University of Michigan, Ann Arbor, MI, - - 2009
We describe the first mapping of biological current in a live heart using ultrasound current source density imaging (UCSDI). Ablation procedures that treat severe heart arrhythmias require detailed maps of the cardiac activation wave. The conventional procedure is time-consuming and limited by its poor spatial resolution (5-10 mm). UCSDI can ...
Kawada Toru - - 2009
To better understand the pathophysiological role of angiotensin II (ANG II) in the dynamic autonomic regulation of heart rate (HR), we examined the effects of intravenous administration of ANG II (10 microg.kg(-1).h(-1)) on the transfer function from vagal or sympathetic nerve stimulation to HR in anesthetized rabbits with sinoaortic denervation ...
Kane Abdoul - - 2009
Local field potentials (LFPs) were recorded in 13 patients from pairs of microelectrodes driven through thalamus during functional localization prior to implantation of a thalamic deep brain stimulation electrode for treatment of tremor or pain. Six patients had a history of essential tremor (ET), 3 of multiple sclerosis, and the ...
Yamamoto Maki - - 2009
The characteristics of autonomic nervous activity were examined on captive great cormorants Phalacrocorax carbo hanedae, using a power spectral analysis of heart rate variability. Heart rates were calculated from recordings of the electrocardiograms of the birds via embarked data loggers. We investigated the effects of blockades of the sympathetic or ...
Mainardi Luca T - - 2009
In the last decades, one of the main challenges in the study of heart rate variability (HRV) signals has been the quantification of the low-frequency (LF) and high-frequency (HF) components of the HRV spectrum during non-stationary events. At this regard, different time-frequency and time-varying approaches have been proposed with the ...
Carignan Benoit B Département de Kinanthropologie, Université du Québec à Montréal, 1205, rue St-Denis, Montreal, QC, - - 2009
The objective of this study was to determine whether it was possible to voluntarily modulate physiological tremor (PT), i.e., reduce its amplitude. We recorded the postural index finger tremor of 30 healthy participants with a laser in four conditions: (A) eyes closed, without any attempt to modulate PT amplitude, (B) ...
Wu Shr-Da - - 2010
The cardiac and respiratory systems can be viewed as two self-sustained oscillators with various interactions between them. In this study, the cardiorespiratory phase synchronization (CRPS) quantified by synchrogram was investigated to explore the phase synchronization between these two systems. The synchrogram scheme was applied to electrocardiogram (ECG) and respiration signals. ...
Pelling Andrew E - - 2009
The mechanical oscillation of the heart is fundamental during insect metamorphosis, but it is unclear how morphological changes affect its mechanical dynamics. Here, the micromechanical heartbeat with the monarch chrysalis (Danaus plexippus) during metamorphosis is compared with the structural changes observed through in vivo magnetic resonance imaging (MRI). We employ ...
Meste Olivier O Lab. I3S UNSA-CNRS, University of Nice-Sophia Antipolis, France. - - 2009
It has been shown that a pedaling frequency component can be extracted from the heart rate variability (HRV) signal using a time-varying filter. It is shown that this filter can be implemented directly in the time-frequency plane with different approaches. The need of resampling the data is also discussed with ...
Uhríková Zdenka Z Faculty of Electrical Engineering, Czech Technical University in Prague, Karlovo nám. 13, 121 35 Prague 2, Czech Republic. - - 2009
This paper focuses on tremor frequency analysis from the video sequence. In order to analyse the video data, the signal needs to be extracted from the video using the intensity change of the local area in time. Next, the power spectral density is used for the frequency estimate from the ...
Garde Ainara A Dept. of ESAII, Universitat Politécnica de Catalunya (UPC), Institut de Bioenginyeria de Catalunya (IBEC) and CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN). c/. Pau Gargallo, 5, 08028, Barcelona, Spain. - - 2009
A correntropy-based technique is proposed for the analysis and characterization of respiratory flow signals in chronic heart failure (CHF) patients with both periodic and nonperiodic breathing (PB and nPB), and healthy subjects. Correntropy is a novel similarity measure which provides information on temporal structure and statistical distribution simultaneously. Its properties ...
Yacin S S Biomedical Engineering Group, Department of Applied Mechanics, Indian Institute of Technology Madras, Chennai-600036, India. - - 2009
Photoplethysmography (PPG) is typically used to extract cardiac-related information like heart rate and cardiac output, though extra-cardiac information like respiratory rate can also be extracted from PPG. The aim of the current study is to advance this approach further and investigate existence of gastric-related activity in PPG. To this end, ...
Maki Hiromichi - - 2009
We have developed a heart rate, respiration rate, posture, behavior and activity data acquisition system for monitoring certain health and activity features during daily life. The recording system consists of one tri-axis accelerometer, six low-power active filters, a low-power 8-bit microcontroller (MC) and a 128MB compact flash memory (CFM). The ...
Lacount Lt - - 2009
A visual display of stripes was used to examine cardio-vagal response to motion sickness. Heart rate variability (HRV) was investigated using dynamic methods to discern instantaneous fluctuations in reaction to stimulus and perception-based events. A novel point process adaptive recursive algorithm was applied to the R-R series to compute instantaneous ...
Mamorita N - - 2009
OBJECTIVES: The aim of the study was to develop a low-cost and compact system for analysis of tremor using a three-axis accelerometer (the Wii Remote (Nintendo)). To analyze tremor, we hypothesized that the influence of gravitational acceleration should be separated from that of movement. This hypothesis was tested experimentally and ...
Widjaja Ferdinan F Biorobotics Group, School of Mechanical and Aerospace Engineering in Nanyang Technological University, Singapore. - - 2009
The recorded motion from (pathological) tremor patient may consist of the involuntary tremulous component and the intended motion. These two components have to be separated so that the actuation part will be able to suppress only the tremor. This paper proposes an algorithm to remove the intended motion by using ...
Shafqat K K Engineering and Mathematical Sciences (SEMS), City University, London, UK. - - 2009
Spectral analysis of Heart Rate Variability (HRV) is used for the assessment of cardiovascular autonomic control. In this study data driven adaptive technique Empirical Mode Decomposition (EMD) and the associated Hilbert spectrum has been used to evaluate the effect of local anesthesia on HRV parameters in a group of fourteen ...
Vinjamuri Ramana - - 2009
This paper proposes an efficient method to acquire sources of tremor in patients with movement disorders based on blind source separation of convolutive mixtures. The extracted sources indicated neural activities that might be generated in the central nervous system. Four patients with essential tremor were tested in a set of ...
Borna Amir A Center for Wireless Integrated Microsystems, University of Michigan, Ann Arbor, Michigan, - - 2009
A small (<1cm(3)), light-weight (<1g including batteries), low power (10mW, lasts 25 hrs), long range (22 ft.), 3-channel wireless neural recording system is designed, fabricated and characterized through in-vitro and in-vivo experiments. The transmitter comprises of an ASIC fabricated in 2-Poly, 2-Metal 1.5 microm AMIS process which can transmit data ...
Javed Faizan F School of Electrical Engineering and Telecommunications, The University of New South Wales, Sydney, NSW, 2052, Australia. - - 2009
This paper reports changes in the spectral powers of finger photoplethysmographic waveform variability (PPGV) following hemodialysis compared to pre-dialysis. The results are based on data collected from 12 hemodynamically stable patients having regular hemodialysis thrice weekly. Six minutes of continuous electrocardiogram (ECG) and finger infra-red photoplethysmographic (PPG) signals were collected ...
Aubert Andr?? E - - 2009
OBJECTIVE: This study examined the effects of hypnosis on autonomic cardiac control. We hypothesized a modification of autonomic modulation of the heart rate with an enhanced vagal tone during hypnosis compared to baseline. METHODS: In 12 healthy subjects (6 men and 6 women, 22.2 +/- 1.0 years of age) ECG ...
Shafqat K K Engineering and Mathematical Sciences (SEMS), City University, London, UK. - - 2009
Spectral analysis of Heart Rate Variability (HRV) can be used for the assessment of cardiovascular autonomic control. In this study Smoothed-Pseudo Wigner-Ville Distribution (SPWVD) has been used to evaluate the effect of local anesthesia on HRV parameters in a group of fourteen patients undergoing brachial plexus block (local anesthesia) using ...
Saini B S BS Department of Electronics & Communication Engineering, Dr. B. R. Ambedkar National Institute of Technology, Jalandhar, 144011, India. - - 2009
In this paper an over-complete discrete wavelet transform (OCDWT) algorithm, obtained by blending two wavelet transform implementations that is redundant wavelet transform and the Mallat's multiresolution decomposition, has been proposed to retrieve the time-varying characteristics of HRV under two different postures, supine and standing. The OCDWT algorithm is critically sub-sampled ...
Hellwig B - - 2009
OBJECTIVE: There is evidence that the tremor frequency in essential tremor (ET) decreases with time. Longitudinal studies on the evolution of tremor frequencies in Parkinson's disease (PD) have so far not been published. Here, we present a longitudinal analysis of tremor frequencies in PD and ET. METHODS: We analyzed the ...
Tang Wen-Tzu - - 2008
A postural tremor appears whenever someone attempts to maintain a steady position against gravity. We examined the postural tremor that occurred while air pistol shooters were taking aim so as to compare the coordinative control of the shooters and to identify the features critical to successful shooting. Ten elite and ...
Brown S J - - 2009
Human ECG records were analyzed during supine (SUP) rest and whole body 80 degrees head-up tilt (HUT), with a respiratory acidosis (5%CO(2)) and breathing room air (RA). HUT increased heart rate in both conditions (RA(SUP) 60 +/- 13 vs. RA(HUT) 79 +/- 16; 5%CO(2SUP) 63 +/- 12 vs. 5%CO(2HUT) 79 ...
Masè Michela - - 2009
Respiratory sinus arrhythmia (RSA) is generally known as the autonomically mediated modulation of the sinus node pacemaker frequency in synchrony with respiration. Cardiorespiratory interactions have been largely investigated during sinus rhythm, whereas little is known about interactions during reentrant arrhythmias. In this study, cardiorespiratory interactions at the atrial and ventricular ...
Umapathy Karthikeyan - - 2009
Ventricular fibrillation (VF) is a medical condition that occurs due to rapid and irregular electrical activity of heart. If undiagnosed or untreated, VF leads to sudden cardiac death. VF has been studied by researchers for over 100 years to elucidate the mechanism that maintains VF, and thus to arrive at ...
Thompson Stewart - - 2008
Behavioral responses to light indirectly affect cardiovascular output, but in anesthetized rodents a direct effect of light on heart rate has also been described. Both the basis for this response and the contribution of rods, cones and melanopsin-based photosensitive retinal ganglion cells (pRGCs) remains unknown. To understand how light acutely ...
González-Landaeta R - - 2008
We propose a novel technique for beat-to-beat heart rate detection based on the ballistocardiographic (BCG) force signal from a subject standing on a common electronic weighing scale. The detection relies on sensing force variations related to the blood acceleration in the aorta, works even if wearing footwear and does not ...
Bellieni C V CV Department of Paediatrics, Obstetrics and Reproductive Medicine, University of Siena, Italy. - - 2008
Incubators are largely used to preserve preterm and sick babies from postnatal stressors, but their motors produce high electromagnetic fields (EMFs). Newborns are chronically exposed to these EMFs, but no studies about their effects on the fragile developing neonatal structure exist. To verify whether the exposure to incubator motor electric ...
Estañol Bruno - - 2008
OBJECTIVE OF THE STUDY: The skin blood flow (SBF) has been known to oscillate in frequency and amplitude. The nature and type of these oscillations have remained obscure. We studied the oscillations of the SBF in frequency and amplitude with non invasive techniques during normal breathing at rest and compared ...
Birdno Merrill J MJ Biomedical Engineering, Duke University, Duke University Medical Center, Durham, North Carolina 27708-0281, - - 2008
The frequency of stimulation is one of the primary factors determining the effectiveness of deep brain stimulation (DBS) in relieving tremor. DBS efficacy, however, may depend not only on the average frequency of stimulation, but also on the temporal pattern of stimulation. We conducted intraoperative measurements of the effect of ...
Sowman Paul F - - 2008
Normal physiological tremor of the jaw has a frequency of 6 to 8 Hz. A patient is described with jaw tremor at frequencies of 12 Hz during jaw movement and 15 Hz when the jaw was relaxed. The 15 Hz tremor was driven by synchronous, bilateral bursts of activity in ...
Min Kyoung-Bok - - 2008
Air pollution, both particulate and gaseous, is known to cause adverse health effects and is associated with increased cardiovascular mortality and morbidity. With a growing recognition in the importance of the autonomic nervous system in air pollution, we examined the effects of air pollutants, namely, particulate matter (PM10), sulfur dioxide ...
Vogel Stefan S Institute for Medical Information Technology, RWTH Aachen University, 52074, Germany. - - 2008
Cardiovascular diseases are among the most common causes of death in developed industrial nations. It is of great interest of both physician and patient to determine the cardiovascular risk factors early in order to take preventive measures. To assist these investigations we develop a wearable in-ear measuring system (IN-MONIT) for ...
Shahsavari Sima S Department of Signals and Systems Chalmers University of Technology, Sweden. - - 2008
A new approach to locate different components of ICP signal for each cardiac induced ICP beat is presented. In this method an initial timing map is used to define the appropriate part of the ICP wave which should be searched for the specific component. In parallel a recently proposed method ...
Diamond Solomon Gilbert - - 2008
The authors investigated whether heart-rate variability can serve as a device for real-time quantitative measurement of hypnotic depth. This study compared the continuous self-rated hypnotic depth (SRHD) of 10 volunteers with heart rate, amplitude, and frequency changes from a time-frequency analysis of heart-rate variability (HRV). The authors found significant linear ...
Santarcangelo Enrica L - - 2008
Subjects with high (Highs) and low (Lows) susceptibility to hypnosis show differences in the sensory-motor integration for postural control and in the cardiovascular response to stress and experimental pain. Aim of the experiment was to assess whether the cardiac response to gravity-related stimulation depending on changes in the body position ...
Bilodeau Martin - - 2009
The aim of this study was to assess differences in physiological tremor amplitude of the hand between the dominant and non-dominant side of right-handed individuals. Mechanical loading of the hand and frequency analysis were used in an attempt to identify the physiological mechanisms involved in observed differences. Seventeen healthy right-handed ...
Hansson-Sandsten Maria - - 2007
In this paper, we evaluate the correlation estimate, based on multiple window spectrum analysis, between the respiratory center frequency and the high-frequency band of the heartrate variability (HRV) power. One aim is to examine whether a more restricted frequency range would better capture respiratory related HR variation, especially when the ...
Singh J - - 2007
In the present paper analysis of phonocardiogram (PCG) records are presented. The analysis has been carried out in both time and frequency domains with the aim of detecting certain correlations between the time and frequency domain representations of PCG. The analysis is limited to first and second heart sounds (S1 ...
Zhong Yuru - - 2007
Cardiac sympathetic and parasympathetic neural activities have been found to interact with each other to efficiently regulate the heart rate and maintain homeostasis. Quantitative and noninvasive methods used to detect the presence of interactions have been lacking, however. This may be because interactions among autonomic nervous systems are nonlinear and ...
Sowman Paul F PF Research Centre for Human Movement Control, Discipline of Physiology, School of Molecular and Biomedical Sciences, University of Adelaide, Adelaide, SA, - - 2008
We have previously shown that the application of anaesthesia to periodontal mechanoreceptors (PMRs) dramatically reduces the 6-12 Hz physiological tremor (PT) in the human mandible during constant isometric contractions where visual feedback is provided. This current study shows that during a ramp contraction where force is slowly increased, the amplitude ...
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