This paper presents an analysis of the effects of RF filter characteristics on the system performance of an impulse radio. The impulse radio system transmits modulated pulses having very short time duration. Information can be extracted in the receiver side based on the crosscorrelation between received and reference pulses. Accordingly, the pulse distortion due to in-band group delay variation...

background : hepatopulmonary syndrome (hps) refers to arterial hypoxemia caused by pulmonary vasodilation, which is a consequence of portal hypertension. hps is associated with increased morbidity and mortality; thus, it is important to diagnose this entity as soon as possible for treatment to be administered. materials and methods: in a cross-sectional study, 40 children (6 months to 14 years ...

Central blood pressure waveforms contain specific features related to cardiac and arterial function. We investigated posture-related changes in ventriculoarterial hemodynamics by means of carotid artery (CA) pulse wave analysis. ECG, brachial cuff pressure, and common CA diameter waveforms (by M-mode ultrasound) were obtained in 21 healthy volunteers (19-30 yr of age, 10 men and 11 women) in su...

A distributed waveform generator (DWG) with DAC-assisted pulse generators is presented for the ultrafast waveform generation. It time-interleaves multiple pulse generators, and uses an on-chip transmission line for wideband pulse combining. Each unit pulse generator adopts a new currentsteering topology which incorporates the edge combiner into the conventional current-steering structure for hi...

OBJECTIVE The aim of the study was to develop a computational method for the assessment of brain pressure compensation of cerebrospinal arterial blood inflow. The method was verified using clinical recordings performed during infusion studies in a group of patients diagnosed with hydrocephalus. MATERIALS AND METHODS We studied 27 patients suspected of having normal pressure hydrocephalus. The...

OBJECTIVE There are many similarities between the photoplethysmography(PPG) pulse wave and the radial pulse when a body is in a stationary state, but the difference between them under conditions of movement is not yet clear. Finding these differences may help further understanding of the cardiovascular system. METHODS PPG and radial pulse wave were recorded simultaneously while subjects were ...

Advanced hemodynamic monitoring is necessary for many patients with acute brain and/or spinal cord injury. Optimizing cerebral and systemic physiology requires multi-organ system function monitoring. Hemodynamic manipulations are cardinal among interventions to regulate cerebral perfusion pressure and cerebral blood flow. The pulmonary artery catheter is not any more the sole tool available; le...

Pulse transit Time (PTT) is a physiological parameter that based on characteristics of the pulse waveform, direct indicator Cardiovascular Diseases (CVD). The defined as time taken for arterial to travel from heart peripheral site. It commonly derived Electrocardiogram (ECG) and Photoplethysmogram (PPG) signal calculations calculated interval between peak electrocardiogram R-wave point photople...

OBSTRUCTIVE SLEEP APNEA (OSA) APPEARS TO BE AN INDEPENDENT RISK FACTOR FOR DIURNAL SYSTEMIC HYPERTENSION,1-3 although the biologic markers for this association have not been well worked out. Acute systemic blood pressure (BP) perturbations have been well described in association with obstructive events in patients with OSA,4-8 but arterial vasomotor activity, which may influence BP activity in ...