Attenuation estimation and imaging in the cervix has been utilized to evaluate the onset of cervical ripening during pregnancy. This feature has also been utilized for the acoustic characterization of leiomyomas and myometrial tissue. In this paper, we present direct narrowband substitution measurement values of the variation in the ultrasonic attenuation coefficient in ex vivo human uterine an...

Breast density is more and more considered as an important risk factor for breast cancer and several quantitative breast density evaluation methods have been proposed. The reference material for simulation of the breast attenuation properties of glandular and adipose breast tissues is manufactured by a single provider. In order to characterize the attenuation properties of these materials, meas...

Introduction: Total Skin Electron Therapy (TSET) and Total Body Irradiation (TBI) are kinds of treatment which use electron and photon beams to treat special types of cancers. The aim of these techniques are to deliver uniform dose to the entire skin while minimizing delivered dose to organs at risk. To check the homogeneity of dose delivery in TBI and TSET, using a humanoid ph...

The ultrasound attenuation coefficient and dispersion from 0-70 MHz in whole human blood and its components (red blood cells and plasma) at 37°C is reported. The measurements are made using a fixed path substitution technique that exploits optical mechanisms for the generation and detection of ultrasound. This allows the measurements to cover a broad frequency range with a single source and rec...

In previous work, we demonstrated that accurate backscatter coefficient measurements are obtained with a data reduction method that explicitly accounts for experimental factors involved in recording echo data. An alternative, relative processing method for determining the backscatter coefficient and the attenuation coefficient is presented here. This method involves comparison of echo data from...

Introduction: Protecting the vital organs in radiation therapy is one of the most important issues. Cerrobend alloy, the most common material used as the shield, is melted several times and used for different patients. In this study changes in attenuation coefficient of cerrobend due to melting was investigated.   Materials and Methods: In melting furnace, ...

The detection of scattered radiation can be a major source of systematic errors when measuring the X-ray linear attenuation coefficient, m. Angular distributions of scattered photons are studied for Z 1⁄4 1 to 20 at energies 6 keV to 100MeV, using tabulated atomic form factors and incoherent scattering functions. A circularly symmetric pencil beam irradiation geometry is considered, and scatter...

The bubbles involved in sonochemistry and other applications of cavitation oscillate inertially. A correct estimation of the wave attenuation in such bubbly media requires a realistic estimation of the power dissipated by the oscillation of each bubble, by thermal diffusion in the gas and viscous friction in the liquid. Both quantities and calculated numerically for a single inertial bubble dri...

Submersed aquatic vegetation (SAV) is an important component of shallow water estuarine systems that has declined drastically in recent decades. SAV has particularly high light requirements, and losses of SAV have, in many cases, been attributed to increased light attenuation in the water column, frequently due to coastal eutrophication. The desire to restore these valuable habitats to their hi...