We have recently reported a systematic variation in integrated ultrasonic backscatter throughout the cardiac cycle in canine hearts. This study was performed to determine whether the pattern of such variation is modified systematically by ischemia. Measurements of integrated ultrasonic backscatter in selected regions of normal, ischemic, and reperfused hearts were compared in view of known diff...

The elastic, two-component algorithm is the most common inversion method for retrieving the aerosol backscatter coefficient from ground- or space-based backscatter lidar systems. A quasi-analytical formulation of the statistical error associated to the aerosol backscatter coefficient caused by the use of real, noise-corrupted lidar signals in the two-component algorithm is presented. The error ...

An analysis of Clementine data obtained from a UVVIS camera and simulating laboratory photometric and polarimetric measurements is presented with the use of a new photometric threeparameter function combining the shadow-hiding and coherent backscatter mechanisms. The fit of calculated curves to the average brightness phase function of the Moon derived from Clementine data indicates that the coh...

Variability in echo intensities from aquatic organisms is caused by physical factors associated with the transmission of sound through water, and by biological factors associated with the ontogeny, physiology, and behaviour of targets. Acoustic-based density estimates depend on accurately characterizing reflected or backscattered sound from any species of interest. Digitized lateral and dorsal ...

Backscatter is the process of energy transfer from small to large scales in turbulence; it is crucially important in the inverse energy cascades of two-dimensional and quasigeostrophic turbulence, where the net transfer of energy is from small to large scales. A numerical scheme for stochastic backscatter in the two-dimensional and quasigeostrophic inverse kinetic energy cascades is developed a...

STATEMENT OF PROBLEM For some patients, radiation treatment is a part of tumor therapy in the head and neck area before and/or after surgery. The oral cavity and teeth are thereby frequently exposed to high doses of radiation. In this situation, electronic backscatter from dental materials may damage the surrounding soft tissue. PURPOSE This study determined the degree of absorption and the b...

This paper presents a study to demonstrate the potential of a spaceborne u-band scatterometer to monitor global snow cover. Global u-band data were acquired by the National Aeronautics and Space Administration (NASA) Scatterometer (NSCAT) operated on the Advanced Earth Observing Satellite (ADEOS) from September 1996 to June 1997. NSCAT backscatter patterns over the northern hemisphere reveals b...

A variation of the conventional combined Raman-elastic backscatter lidar method, the 1-2-3 lidar method, is described and analyzed. This method adds a second transmitter wavelength to the conventional combined Raman-elastic backscatter lidar. This transmitter wavelength is identical to that of the Raman receiver. One can generate the transmitted beam at this wavelength by Raman shifting the las...

To determine whether collagen content may be a determinant of the ultrasonic attenuation and backscatter in myocardium and to identify factors in the measurement of the backscatter coefficient needed for ultrasonic characterization of myocardium in vivo, two series of experiments were conducted. In the first series, the ultrasonic attenuation was measured from 110 regions in 18 dogs studied 2, ...