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The following topics are dealt with: Biomedical Imaging & Image Processing; Biomedical Signal Processing; Medical Diagnostics and Biomarkers; Cardiovascular & Respiratory Systems Engineering; Neural Engineering & Rehabilitation Engineering; Bioinformatics & Computational Biology, Systems Biology & Modelling Methodologies and Bioinstrumentation, Biosensors, & Bio-Micro-Nano...
Airway hyperresponsiveness and obstruction are the major characteristics of asthma. Current asthma treatments using anti-inflammatory agents and airway smooth muscle (ASM) relaxants are expensive, variable in effectiveness and are associated with several cardiovascular side effects. ASM behaviour in vitro has been studied by various researchers to possibly provide an explanation of its mechanical...
We recently proposed an accelerated dynamic magnetic resonance imaging (MRI) reconstruction algorithm that exploits the underlying low rank and sparse properties of the data to achieve highly accelerated reconstructions. In this paper, we validate our algorithm in the context of dynamic free breathing cardiac Perfusion MRI on the Physiologically Improved Non Uniform Cardiac Torso Phantom, PINCAT phantom...
The purpose of this study was to compare the autonomic signals in response to Classical Turkish Music (CTM) of schizophrenia patients and healthy controls. Respiration and blood volume pulse signals were recorded in the rest and auditory stimulation periods from fifty participants. Respiration rate, heart rate and beat-to-beat interval values were extracted as features. Results indicated that patients...
Accurate attenuation correction (AC) requires matched emission (EM) and transmission (TX) data. For cardiac SPECT imaging with AC, historically TX data is only acquired in a non-gated manner and AC is only performed on the summed EM data. Considering that the reconstruction of the summed EM data can be decomposed into the reconstruction of each gated bin, AC using the same non-gated TX data leads...
A mathematical model of short-term arterial pressure regulation by the carotid baroreflex was integrated with a simple cardiovascular model to study the interactions between the baroreguation and the pusating heart. The cardiovascular system was modeled as an electric circuit, consisting of the left ventricle as a time-varying capacitance, the systemic circulation as a four-element RLC circuit, the...
Ballistocardiography is a non-invasive technique that yields information about the cardiovascular system that is not available in other external signals such as the electrocardiogram (ECG). In the last years, several research groups have obtained the ballistocardiogram (BCG) by using instrumentation methods simpler than those available in the 1950s and that did not progress because of their complexity...
This study investigates the effects of exposure to intermittent hypoxia on cardiovascular autonomic control and metabolic function in obese children with obstructive sleep apnea (OSA). Each subject underwent: (1) a polysomnography; (2) morning fasting blood samples and a subsequent FSIVGTT; (3) noninvasive measurement of respiration, arterial blood pressure, and heart rate during supine and standing...
A correntropy-based technique is proposed for the characterization and classification of respiratory flow signals in chronic heart failure (CHF) patients with periodic or nonperiodic breathing (PB or nPB, respectively) and healthy subjects. The correntropy is a recently introduced, generalized correlation measure whose properties lend themselves to the definition of a correntropy-based spectral density...
The purpose of this paper is to introduce an accurate algorithm to detect respiration rate and heart beat using an Ultra-Wideband (UWB) signal. One important issue to consider for obtaining precise results is the right selection of measurement parameters in UWB system. In this work the impact of these parameters in detecting respiration rate and heart beat are studied and the best values are suggested...
Slow and regular breathing can make beneficial effects on cardiovascular system and autonomic nerve system. Many researches studied the cardiovascular variabilities under paced breathing rate of 0.25 Hz and 0.1 Hz, but few quantitative data are available describing the relationships between the cardiovascular variables during the slow and regular breathing procedure, and mechanism of the beneficial...
Understanding the variability of the cardiac-related signals caused by physical exercise is an interesting and important problem. To our knowledge, there is no paper evaluating the biometric consistency of the cardiovascular based signals during the physical exercise, or the extent to which the signals can recover after that. A novel method of remotely sensing mechanical activity related to the carotid...
Quantitative evaluation of respiratory sinus arrhythmia (RSA) may provide important information in clinical practice of anesthesia and postoperative care. In this paper, we apply a point process method to assess dynamic RSA during propofol general anesthesia. Specifically, an inverse Gaussian probability distribution is used to model the heartbeat interval, whereas the instantaneous mean is identified...
We developed a new comprehensive cardiopulmonary model that takes into account the mutual interactions between the cardiovascular and the respiratory systems along with their short-term regulatory mechanisms. The model includes the heart, systemic and pulmonary circulations, lung mechanics, gas exchange and transport equations, and cardio-ventilatory control. Results show good agreement with published...
In this paper, experimental result using a 5.8 GHz Doppler radar to monitor the variations of vital signs of an infant simulator under different medical conditions is presented. The infant simulator can mimic cardiovascular derangements seen in critically ill infants. The result demonstrates the system is capable of tracking a majority of the changes in heart rate and respiratory rate. Analysis suggests...
A 5.8-GHz ISM-Band radio-frequency sensor has been developed for non-contact measurement of respiration and heart rate from stationary and semi-stationary subjects at a distance of 0.5 to 1.5 meters. We report on the accuracy of the heart rate measurements obtained using two algorithmic approaches, as compared to a reference heart rate obtained using a pulse oximeter. Simultaneous Photoplethysmograph...
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 the transarterial technique. Instead of using the fixed...
Intracellular regulation of myocardial Ca2+ has long been of interest to physiologists. The force-interval relationship provides a phenomenological approach that permits insight into aspects of calcium regulation. The response to an extrasystole is a potentiation in contractile force and the recovery in contractile force is described by the recirculation fraction (RF). The RF provides a gross estimation...
Computed tomography is not the most frequent radiologic imaging procedure, but is arguably the most important in terms of clinical impact. CT is used extensively for emergencies, cardiovascular, pulmonary, gastrointestinal, endocrine, neurological, orthopedic and other applications - often as the first and only imaging procedure needed for diagnosis. The chances are very high that a patient will have...
Airflow in the respiratory system is complicated as it goes through various regions with different geometries and mechanical properties. Three-dimensional (3-D) simulations are typically limited to local areas of the system because of their high computational cost. On the other hand, the one-dimensional (1-D) equations of flow in compliant tubes offer a good compromise between accuracy and computational...
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