Purpose: Underdosage in the human larynx may be the true factor behind the decrease in local control rates.
Patients And Methods: To evaluate underdosage with Monte Carlo a CT-based geometrical model of the patient's neck (mathematical neck) was created. Dose was calculated for a pair of 6 Me V parallel-opposed photon beams modulated with 15 degree steel wedges.
Results: At least 5% of volume of 3.5 cm(3) hypothetical tumor near the air wall of the larynx receives less than 86% of the maximum tumor dose. The same volume received less than 91% of the maximum tumor dose when the mathematical neck had no air cavities.
Conclusions: We conclude the significant underdosage at the air-tissue interface in the larynx occurs in traditional radiotherapy treatments, especially in the glottic part of the larynx.
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http://dx.doi.org/10.1016/j.radonc.2005.11.010 | DOI Listing |
Environ Geochem Health
January 2025
Shandong Bureau of China Metallurgical Geology Bureau, Qingdao, 266109, China.
The natural environment and public health are gravely threatened by the enrichment of soil potentially toxic elements (PTEs). To explore the contamination level, sources and human health risks posed by PTEs, high-density soil sampling was carried out in the upper Wei River region (UWRR). The results demonstrated that the pollution risk and ecological risk in UWRR as a whole were at a low level, but there were moderate or higher ecological risks of Hg and Cd in some areas.
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January 2025
School of Physics and Electronic Engineering, Sichuan University of Science and Engineering, Yibin, 644005, China.
The three-dimensional radiation field is an important database reflecting the radioactivity distribution in a nuclear facility. It is of great significance to accurately and quickly grasp the radiation dose field distribution to implement radiation protection. Presently, majority of radiation field reconstruction algorithms concentrate on two-dimensional reconstruction and can only measure on a regular grid.
View Article and Find Full Text PDFWater Res
January 2025
CAS Key Laboratory of Mountain Ecological Restoration and Bio-resources Utilization, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China. Electronic address:
Microplastics (MPs) in aquatic environments has been observed globally. However, the ecological risks of MP pollution in riverhead prior to highly urbanized region remain poorly understood. This study investigated MP pollution related to microbiome in sediments, and ecological risks of MPs in riverhead prior to urbanized area over 291 km of Minjiang River (MJR) in Qinghai-Tibetan Plateau (QTP).
View Article and Find Full Text PDFPhys Med Biol
January 2025
CREATIS, INSA de Lyon, Bâtiment Blaise Pascal, 7 Avenue Jean Capelle, Villeurbanne, 69621 Cedex , FRANCE.
Compton cameras are imaging devices that may improve observation of sources of γ photons. We present CoReSi, a Compton Reconstruction and Simulation software implemented in Python and powered by PyTorch to leverage multi-threading and for easy interfacing with image processing and deep learning algorithms. The code is mainly dedicated to medical imaging and for near-field experiments where the images are reconstructed in 3D.
View Article and Find Full Text PDFPhys Med Biol
January 2025
Industrial Engineering, Universita degli Studi di Roma Tor Vergata, Via del Politecnico,1, Roma, 00133, ITALY.
The increasing interest in hadron therapy has heightened the need for accurate and reliable methods to assess radiation quality and the biological effectiveness of particles used in treatment. Microdosimetry has emerged as a key tool for this, demonstrating its potential, reliability, and suitability. In this context, solid-state microdosimeters offer technological advantages over traditional Tissue-Equivalent Proportional Counters, and recent advancements have further improved their performance and reliability.
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