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An Addendum to the AAPM's TG-51 protocol for the determination of absorbed dose to water is presented for electron beams with energies between 4 MeV and 22 MeV ( ). This updated formalism allows simplified calibration procedures, including the use of calibrated cylindrical ionization chambers in all electron beams without the use of a gradient correction. New data are provided for electron beams based on Monte Carlo simulations. Implementation guidance is provided. Components of the uncertainty budget in determining absorbed dose to water at the reference depth are discussed. Specifications for a reference-class chamber in electron beams include chamber stability, settling, ion recombination behavior, and polarity dependence. Progress in electron beam reference dosimetry is reviewed. Although this report introduces some major changes (e.g., gradient corrections are implicitly included in the electron beam quality conversion factors), they serve to simplify the calibration procedure. Results for absorbed dose per linac monitor unit are expected to be up to approximately 2 % higher using this Addendum compared to using the original TG-51 protocol.
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http://dx.doi.org/10.1002/mp.17277 | DOI Listing |
Adv Healthc Mater
September 2025
Department of Mechanical Engineering, University of Arkansas, Fayetteville, AR, 72701, USA.
3D scaffold architecture is critical for directing human neural stem cell (hNSC) fate and spatial organization. In this study, two-photon lithography (TPL) is used to fabricate microcapillary scaffolds based on the Hilbert space-filling curve as biomimetic basement membrane structures for guiding hippocampal-derived hNSC differentiation. The scaffolds feature 80 µm lumens with porous ellipsoidal membranes suspended above the substrate to provide topographical cues and permit nutrient diffusion while maintaining mechanical stability.
View Article and Find Full Text PDFInt J Implant Dent
September 2025
Biomaterials Research Group, UWA Dental School, the University of Western Australia, Perth, Australia.
Introduction: Peri-implantitis (PI) is a biofilm-related condition driven by bacterial colonization on dental implant surfaces, leading to inflammation of the peri-implant connective tissue and progressive bone loss. Despite advancements, effective strategies for eradicating these biofilms remain elusive. While high-intensity focused ultrasound (HIFU) has been popularized in medicine, its effects on dental implant-attached biofilms remain unclear.
View Article and Find Full Text PDFJ Appl Clin Med Phys
September 2025
Department of Radiation Oncology, Juntendo University, Graduate School of Medicine, Bunkyo-ku, Tokyo, Japan.
Background: Extending the source-to-surface distance (SSD) is an effective approach to cover a large irradiation area in electron beam therapy for large planning target volumes (PTVs). However, the accuracy of dose calculations at extended SSDs has not been fully validated.
Purpose: This study evaluated the dose calculation accuracy of the electron Monte Carlo (eMC) algorithm implemented in Varian's Eclipse radiation therapy planning system (RTPS) under extended SSD conditions.
Sensors (Basel)
August 2025
Institute of Space Science, Subsidiary of INFLPR, 409 Atomistilor Street, 077125 Magurele, Ilfov, Romania.
We present a Geant4-based simulation study of the electromagnetic sampling calorimeter (ECAL) foreseen in the LUXE experiment. The ECAL will enable precise measurement of the number and energy spectrum of positrons and electrons. The electromagnetic shower response, energy resolution, and linearity-properties that are essential for physics research-are studied.
View Article and Find Full Text PDFPolymers (Basel)
August 2025
Basic Sciences Research Center (BSRC), Deanship of Scientific Research, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh 11623, Saudi Arabia.
This work analyzes the radiation shielding effectiveness of biocompatible hydrogel pads containing carbohydrate-based polymer matrices (Alginate, Chitosan, and Cellulose) integrated with the high atomic number (Z) fillers Bismuth Oxide (BiO) and Zinc Oxide (ZnO). The Monte Carlo-based toolkit, Geant4, was used to simulate the deposition of the dose throughout a multilayer phantom that mimics the skin (Epidermis, Dermis, Subcutaneous, and Muscle) with a pad on top irradiated with photon and electron beams from 50 keV to 1000 keV. The results indicated that BiO succeeded in causing greater absorption of photons at doses, particularly in deep-layer tissues, from the increase in the filler content as well as the pad thickness.
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