BACKGROUND Guidelines for the 2-min tidal-breathing and the five-breath dosimeter methods for methacholine challenge have recently been published by the American Thoracic Society (ATS). Although subjects are exposed to twice as much aerosol at any given concentration during the tidal-breathing method compared to the dosimeter method, they were thought to give equivalent results. OBJECTIVE To ...

Bronchial reactivity is being measured with increasing frequency in epidemiological studies, but there debate continues about the relative merits of the different methods used to measure reactivity, particularly for subjects with no previous experience of reactivity testing as is the case in epidemiological studies. Repeatability is likely to improve with practice, and laboratory based studies ...

Gafchromic films are increasingly being used for dosimetry in medical and industrial applications of ionizing radiation because of their favorable characteristics such as self developing in nature, easy to handle, dose rate independent response, insensitivity to normal room lights, high resolution and insensitivity to variation in the environment conditions. The dosimetry measurements using Gaf...

In this study, using methacrylic and ascorbic acid in gelatin initiated by copper (MAGIC-f) polymer gel after megavoltage energy exposure, the sensitivity of the ultrasound velocity and attenuation coefficient dose-dependent parameters was evaluated. The MAGIC-f polymer gel was irradiated under 1.25 MeV cobalt-60, ranging from 0 to 60 Gy in 2-Gy steps, and received dose uniformity and accuracy ...

Introduction: Currently, the potential application of gold nanoparticles (AuNPs) to increase the efficiency of radiation therapy have been investigated. However, the loss of an appropriate method to estimate the dose distribution in nanoparticle laden tissue limits the applicability of nanoparticles in radiotherapy clinics. Polymer gel dosimetry provides an accurate and precise...