Brandon Ngai

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In this paper we demonstrate that SCG can be used to estimate hemodynamic parameters such as stroke volume and the three systolic time intervals of pre-ejection period (PEP), left ventricular ejection time (LVET) and electromechanical systole (QS2).In this study, recordings of suprasternal pulsed Doppler and Impedance cardiogram (ICG) were used as the(More)
Simultaneous seismocardiogram (SCG) and ultra-low frequency ballistocardiogram (BCG) signals are recorded. Preliminary results from the BCG helped tag which waves on the SCG are related to the rapid systolic ejection and aortic valve closure events. These results agreed with and further confirmed previous findings using the echocardiogram. This is the first(More)
New approaches to fairly old noninvasive cardiology tools, based on studying low frequency vibrations created by the heart on the body, were reviewed. These signals were divided and studied in two categories and compared in their capability for estimation of hemodynamic parameters. In particular one representative signal of each category, seismocardiogram(More)
OBJECTIVE Use of vancomycin is a risk factor for acquiring vancomycin-resistant enterococci (VRE). To optimize the use of vancomycin in hospitals, the Hospital Infection Control Practices Advisory Committee (HICPAC) published recommendations in 1995. The objectives of this study were to determine the frequency, indications, and risk factors for(More)
Features are extracted from seismocardiogram data to correlate with two indexes of myocardial contractility: dP/dt(max) (maximum first derivative of left ventricular pressure) and stroke volume. In the first study on three pigs, it is shown that the time period between the R peak of the ECG and the first peak of the SCG (R-AO period or pre-ejection period,(More)
Monitoring of personnel and assets in harsh or remote environments is a great challenge both from the organizational and the technical points of view. Usually, significant infrastructure investments and highly trained personnel are required. We propose a system that employs a wireless mesh sensor network to provide the communication backbone for stationary(More)
A 39-year-old woman presented with an acute left hemisphere stroke and was found to have severe hyperthyroidism. She developed an acute right brachial artery occlusion while under continuous cardiac monitoring, and at no time exhibited atrial fibrillation. This case, and a review of the literature, suggests that thromboembolism occurs in thyrotoxicosis(More)
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