Stable All-Organic Radicals with Ambipolar Charge Transport.

A series of neutral long-lived purely organic radicals based on the stable [4-(N-carbazolyl)-2,6-dichlorophenyl]bis(2,4,6-trichlorophenyl)methyl radical adduct (Cbz-TTM) is reported herein. All compounds exhibit ambipolar charge-transport properties under ambient conditions owing to their radical character. High electron and hole mobilities up to 10 and 10  cm  V  s , respectively, were achieved.

Cardiovascular responses to intrathoracic pressure variations in coronary disease patients: a computer simulation.

Several studies have suggested that the Valsalva maneuver may predispose potential lethal arrhythmias in patients with coronary artery disease, since this maneuver induces diminished coronary flow. On the other hand some studies have suggested that the Valsalva maneuver abruptly reduces determinants of cardiac oxygen demand, relieving angina pectoris. In order to study the variations of the myocardial oxygen supply-demand relation, during different applications of the maneuver, a mathematical model of the human cardiovascular system is presented.

Adaptive filter for event-related bioelectric signals using an impulse correlated reference input: comparison with signal averaging techniques.

Many bioelectric signals result from the electrical response of physiological systems to an impulse that can be internal (ECG signals) or external (evoked potentials). In this paper an adaptive impulse correlated filter (AICF) for event-related signals that are time-locked to a stimulus is presented. This filter estimates the deterministic component of the signal and removes the noise uncorrelated with the stimulus, even if this noise is colored, as in the case of evoked potentials.

Low-pass differentiators for biological signals with known spectra: application to ECG signal processing.

Digital low-pass filtering and differentiation (LPD) are useful in real-time processing of many biomedical signals. A general method is presented for determining the coefficients of a differentiator that maximizes the signal-to-noise ratio or minimizes the error between actual and ideal LPD filters, when signal and noise spectra are known. Several examples of digital filters suitable for QRS complex and P-T wave processing in ECG are presented.