Calibration system correction factor for measuring the reference air kerma rate (RAKR) applied to high dose rateIr sources (HDR).

The aim of this study was to use computer simulation to analyze the impact of the aluminum fixing support on the Reference Air Kerma (RAK), a physical quantity obtained in a calibration system that was experimentally developed in the Laboratory of Radiological Sciences of the University of the State of Rio de Janeiro (LCR-UERJ). Correction factors due to scattered radiation and the geometry of theIr sources were also sought to be determined. The computational simulation was validated by comparing some parameters of the experimental results with the computational results.

Comparison of spectra and mean glandular dose (MGD) with tube voltage used in digital mammography for simulated, metrological and clinical cases.

Mammography has a crucial role in breast cancer detection. The National Cancer Institute (INCA) estimates that 29.7% of the cancer cases in Brazil are related specifically to the breast.

A pilot study of a postal dosimetry system using the Fricke dosimeter for research irradiators.

Cobalt-60 irradiators and soft X-ray machines are frequently used for research purposes, but the dosimetry is not always performed using the recommended protocols. This may lead to confusing and untrustworthy results within the conducted research. Postal dosimetry systems have already been approved by the IAEA, with thermoluminescence dosimeters (TLD) and optically stimulated luminescence (OSL) as the most commonly used dosimeter systems in these cases.

COMPARISON OF SPECTRA AND MEAN GLANDULAR DOSE WITH TUBE VOLTAGES USED IN DIGITAL BREAST TOMOSYNTHESIS FROM SIMULATED, METROLOGICAL AND CLINICAL CASES.

Digital breast tomosynthesis (DBT) is a screening and diagnostic modality that acquires images of a breast at multiple angles during a short scan. The Selenia Dimensions (Hologic, Bedford, Mass) DBT system can perform both full-field digital mammography and DBT. The system acquires 25 projections over a 15° angular range (from -7.

Technical Note: Fricke dosimetry for blood irradiators.

Purpose: The Fricke dosimeter has been shown to be a viable option as an absorbed dose standard. This work aims to provide the dose distribution in an irradiator container during blood irradiation using Fricke dosimetry.

Methods: Measurements were performed using a Gammacell Elan 3000 blood irradiator at Hemocenter in Rio de Janeiro, Brazil.

DNA damage in blood cells exposed to low-level lasers.

Background And Objective: In regenerative medicine, there are increasing applications of low-level lasers in therapeutic protocols for treatment of diseases in soft and in bone tissues. However, there are doubts about effects on DNA, and an adequate dosimetry could improve the safety of clinical applications of these lasers. This work aimed to evaluate DNA damage in peripheral blood cells of Wistar rats induced by low-level red and infrared lasers at different fluences, powers, and emission modes according to therapeutic protocols.

Monte Carlo simulation for the estimation of the glandular breast dose for a digital breast tomosynthesis system.

Digital breast tomosynthesis (DBT) is a screening and diagnostic modality that acquires images of the breast at multiple angles during a short scan. The Selenia Dimensions (Hologic, Bedford, Mass) DBT system can perform both full-field digital mammography and DBT. The system acquires 15 projections over a 15° angular range (from -7.

Up-regulation of angiotensin-converting enzyme and angiotensin II type 1 receptor in irradiated rats.

Purpose: To investigate changes in cardiac functional parameters and the cardiac expression of angiotensin-converting enzyme (ACE), angiotensin II type 1 receptor (AT1), procollagen type I (proc-I) and transforming growth factor-ß1 (TGF-ß1) in rats irradiated at heart.

Material And Methods: Male Wistar rats were irradiated with a single dose of radiation (0, 5, 10 and 15 Gray [Gy]) delivered directly to the heart and the molecular evaluations were performed at various times post-irradiation (two days, 15 days and four months). The expression of ACE, AT1, proc-I and TGF-ß1 were analysed using Real Time-Polymerase Chain Reaction (RT-PCR) and/or Western blotting.