OBJECTIVE To evaluate the reliability of virtual non-contrast (VNC) images reconstructed from contrast-enhanced, dual-energy scans compared with true non-contrast (TNC) images in the assessment of high CT attenuation or calcification of mediastinal lymph nodes. MATERIALS AND METHODS A total of 112 mediastinal nodes from 45 patients who underwent non-contrast and dual-energy contrast-enhanced ...

Background & Aims: Today, different imaging techniques have been studied in the reading of radiationsensitive polymer gels dosage. Due to limitations of imaging techniques such as magnetic resonance imaging (MRI) and computed tomography (CT), ultrasound techniques are proposed for dose-dependent parameter extraction. In this study, using MAGIC-f (methacrylic and ascorbic acid in gelatin initiat...

OBJECTIVE Supra-aural audiometric headphones are generally not recommended for use in measuring the attenuation of earplugs, because contact between the headphone and pinna and/or earplug could alter the attenuation obtained, and because of concerns of non-comparability between modes of excitation from supra-aural headphones and the sound-field procedure required by the standardized method. In ...

background: noise-induced hearing loss (nihl) is one of the most common occupational diseases and the second most common cause of workers' claims for occupational injuries. objective: due to high prevalence of nihl and several reports of improper use of hearing protective devices (hpds), we conducted this study to compare the effect of face-to-face training in effective use of earplugs with app...

Attenuation over distance in natural habitat is often difficult to predict when measured without respect to sound frequency. The physical-acoustic structure of Florida scrub habitat is described and both attenuation and reliability of attenuation are measured as a function of sound frequency, over several distances, speaker elevations, and microphone elevations. The spatial context of sound pro...

Attenuation relation (Ground-motion prediction equation) The term “attenuation relation” is a former short-hand notation in earthquake engineering for “empirical ground-motion attenuation relationship”, now referred to as “ground-motion prediction equation” (GMPE). Attenuation relations represent empirical scaling equations that relate observed ground-motion intensity measures to parameters of ...

Optical computed tomography (optical-CT) and optical-emission computed tomography (optical-ECT) are new techniques for imaging the 3D structure and function (including gene expression) of whole unsectioned tissue samples. This work presents a method of improving the quantitative accuracy of optical-ECT by correcting for the 'self'-attenuation of photons emitted within the sample. The correction...

Quantitative whole-body PET/MR imaging is challenged by the lack of accurate and robust strategies for attenuation correction. In this work, a new pseudo-CT generation approach, referred to as sorted atlas pseudo-CT (SAP), is proposed for accurate extraction of bones and estimation of lung attenuation properties. This approach improves the Gaussian process regression (GPR) kernel proposed by Ho...