OBJECTIVES This study sought to compare contrast-enhanced anatomic imaging and contrast-enhanced tissue characterization (delayed-enhancement cardiac magnetic resonance [DE-CMR]) for left ventricular (LV) thrombus detection. BACKGROUND Contrast echocardiography (echo) detects LV thrombus based on anatomic appearance, whereas DE-CMR imaging detects thrombus based on tissue characteristics. Alt...

An echo canceller removes undesired echo in fullduplex speech communication. The cancellation is done by modeling the echo path impulse response with an adaptive finite impulse response filter and subtracting the echo estimate from the received signal. A typical diagram of an echo canceller is depicted in Figure 1. The signal x(n) and v(n) represent the far-end and near-end speeches respectivel...

Introduction Last year the Dual-Echo PRESTO [l] technique was introduced to measure I0 and T2* simultaneously. This technique is an extension of the PRESTO [2] technique (TE > TR) and allows for the acquisition of two echoes within each TR. The first echo with a short TE (-7 ms) is acquired directly after RF excitation and is immediately followed by an echo with a long TE (-43 ms) which is echo...

In acoustic echo cancelation systems, some residual echo exists after the acoustic echo canceler (AEC) due to the fact that the adaptive filter does not model exactly the impulse response of the Loudspeaker-Enclosure-Microphone (LEM) path.This is specially important in feedback acoustic environments like speech reinforcement systems for cars where this residual echo can make the system become u...

In order to verify the chaff jamming performance, according to the time-frequency distribution and statistical characteristics of chaff echo, this paper presents a modeling and simulation method of chaff echo based on its mechanism of generation, Also it presents a simulation study of chaff echo signal based on LFM signals. The simulation results indicate that the generated chaff echo of this m...

The inherent sensitivity of multiple gradient-echo sequences to the chemical shift is exploited to rapidly map muscle water frequency shifts caused by ultrasonic heating. The use of multiple echoes is shown to offer several advantages over single gradient-echo approaches previously proposed for temperature measurement. An increase in the effective bandwidth significantly reduces aliasing proble...

A theory of optical echo spectroscopies of large polyatomic molecules in condensed phases is developed. Using phase space correlation functions, we examine the interrelationships among the following optical measurements: ordinary photon echo, stimulated photon echo, accumulated photon echo, incoherent accumulated photon echo, and pump-probe absorption. Conditions for the elimination of inhomoge...

BACKGROUND Electrocardiographically-detected left ventricular hypertrophy (LVH) is a strong predictor of cardiovascular morbidity and mortality. OBJECTIVE To assess the performance of the Sokolow-Lyon-Rappaport (SLR) and Cornell voltage criteria in a population sample regarding the diagnosis of LVH on echocardiogram (ECHO). METHODS A total of 641 out of the 682 participants of the second ph...