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Brugada syndrome (BrS) causes sudden death in patients with structurally normal hearts. Manifestation of BrS in the ECG is dynamic and most patients do not show unequivocal signs of the syndrome during ECG screening. Electrograms (EGMs) of BrS patients show conduction delay and fractionation at the right ventricular outflow tract area (RVOT) and thus could be used for diagnosis, but their recording...
Some diseases, such as hypertension, require a close control of the patient's blood pressure. This is even more critical when that patient is going through — or has just underwent — a surgical procedure In such situations, reducing blood pressure to normal levels is of paramount importance. Usually, this demanding and time consuming monitoring is done manually by clinical personnel and are subject...
A prototype endoscope for observing inner wall of large arteries was specially designed and evaluated through in vitro and in vivo tests. The purpose of this endoscope is to visualize the inner wall of large arteries, e.g., an aorta, without blocking off the blood stream aiming for the use of an assistive technique for endovascular interventions such as stent-graft placement for aortic aneurysm. The...
This paper introduces a silicon-based imaging array for remote measurements of complex permittivity of tissue. Using a coherent pulsed measurement approach, this time-frequency resolved technique recovers the three dimensional mapping of electrical properties of the subject in the microwave/millimeter-wave frequency spectrum. Some of the major challenges in the design of the system are described....
Advances in neural electrode technology are enabling brain recordings with increasingly fine spatial and temporal resolution. We explore spatio-temporal (ST) patterns of local field potential spikes using a new high-density active electrode array with 500 μm resolution. We record subdural micro-electrocorticographic (μECoG) signals in vivo from a feline model of acute neocortical epileptiform spikes...
The remote haptic collaboration system between operating and assistant surgeons causes both shift and step delays of force feedback, and then makes users feel coarse reaction forces and different hardness of the object. In this study, we propose a haptic interface protocol for finite-element-method based deformable objects, in order to achieve a high update rate of force calculation. The method exports...
The purpose of this work was to improve the drug dispensing process at the National Institute of Respiratory Diseases of Mexico by applying the six sigma methodology, identifying the non-value added activities as well as the areas of opportunity, in order to make proposals to ensure the supply of prescription drugs to the patient in a timely manner. Seven variables were defined and three indicators...
We evaluated neurovascular and autonomic response to a Divided Attention task within a group of 16 healthy subjects, by means of Electroencephalography, Electrocardiography, functional Near Infrared Spectroscopy techniques, acquired simultaneously. We exctracted Alpha (8–13,5 Hz) and Beta (13,5–30 Hz) power rhythms with a spectral autoregressive residual model, and inter-beat-interval (RR series)...
The early detection of epileptic seizures requires computing relevant statistics from multivariate data and defining a robust decision strategy as a function of these statistics that accurately detects the transition from the normal to the peri-ictal (problematic) state. We model the afflicted brain as a hidden Markov model (HMM) with two hidden clinical states (normal and peri-ictal). The output...
The time-series data analysis described here is based on the simple idea that the accumulation of the effects of lifestyle events, such as ingestion and exercise, could affect personal health with some delay. The delay may reflect complex bio-reactions such as those of metabolism in a human body. In the analysis, the accumulation of the effects of lifestyle events is represented by a summation of...
Multiparameter m-health scenarios with bandwidth demanding requirements will be one of key applications in future 4G mobile communication systems. These applications will potentially require specific spectrum allocations with higher quality of service requirements. Furthermore, one of the key 4G technologies targeting m-health will be medical applications based on WiMAX systems. Hence, it is timely...
High resolution mapping of electrical activity is becoming an important technique for analysing normal and dysrhythmic gastrointestinal (GI) slow wave activity. Several methods are used to extract meaningful information from the large quantities of data obtained, however, at present these methods can only be used offline. Thus, all analysis currently performed is retrospective and done after the recordings...
Currently there is no efficient treatment for patients with severe bilateral vestibular function impairment. Presence of oscillopsia is their main complaint. It has a significant negative impact on their quality of life. Recently it has been shown that angular vestibulo-ocular reflex can be partially restored in animals. In humans it is possible to elicit a nystagmic response by electric stimulation...
Heart failure accounts for over five million patients in the United States alone. Many of them present dyssynchronous left ventricular (LV) contraction, whose treatment by cardiac resynchronization therapy (CRT) is until now guided by electrocardiographic analysis. One third of the selected patients, however, does not respond to the therapy. Aiming at improving the response rate, recent studies showed...
Heart rate variability analysis is fast gaining acceptance as a potential non-invasive means of autonomic nervous system assessment in research as well as clinical domains. In this study, a new nonlinear analysis method is used to detect the degree of nonlinearity and stochastic nature of heart rate variability signals during two forms of meditation (Chi and Kundalini). The data obtained from an online...
A single cuff electrode with multiple-contacts permits fibre selective recording from peripheral nerves. This has been demonstrated in frog nerve in vitro and earth worm before. In this paper we apply this method successfully to the peripheral median nerve of pig in vivo. Compound action potentials (CAPs) were electrically excited at the median nerve close to the wrist of the forelimb. The CAPs were...
Neurobiological processes associated with learning are known to be highly nonlinear, dynamical, and time-varying. Characterizing the time-varying functional input-output properties of neural systems is a critical step to understand the neurobiological basis of learning. In this paper, we present a study on tracking of the changes of neural dynamics in rat hippocampus during learning of a memory-dependent...
Movement misclassifications often occur during real-time pattern recognition control. Majority vote and a decision-based velocity ramp are two different post-processing methods that have been suggested to improve real-time control. With majority vote, spurious misclassifications are removed at the expense of an additional controller delay. With a decision-based velocity ramp, the effect of misclassifications...
Researchers are faced with huge challenges when undertaking BME research projects in developing countries. Various administrative, technical, economic and even cultural barriers have to be overcome whereas the quality and quantity of the output has to be comparable with the developed world in order to make results publishable. This paper uses a real project context to highlight the major problems...
The analysis of human motion data is interesting for the purpose of activity recognition or emergency event detection, especially in the case of elderly or disabled people living independently in their homes. Several techniques have been proposed for identifying such distress situations using either motion, audio or video sensors on the monitored subject (wearable sensors) or the surrounding environment...
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