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Thermal effects under high-power pumping significantly limit the laser beam quality. To address this, we developed an M simulation algorithm based on ray trajectory simulation and established a corresponding experimental platform. This approach optimized the M factor of pulsed lasers to 2.2 and output power of 25.9 W under a repetition rate of 10 kHz. The results revealed that under specific conditions, thermal effects, typically considered detrimental to beam quality, could significantly enhance it. Compared to other methods necessitating additional optical components, our strategy offers a streamlined and straightforward solution for beam quality control under high-power pumping conditions.
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http://dx.doi.org/10.1364/OE.503021 | DOI Listing |
Front Vet Sci
August 2025
Fish Research Centre, Faculty of Environmental Agricultural Sciences, Arish University, El Arish, Egypt.
The well-known technique of microtomy, which is an essential cutting tool, was first developed for light and transmission electron microscope uses, but it is currently also utilized to prepare specimens for atomic force microscopy (AFM), ion microscopy using a focused ion beam (FIB), and scanning electron microscopy (SEM). Ultramicrotomy can only be used on soft substances and metals that are sufficiently ductile to be cut with a diamond knife. Before being sliced by a microtome, many soft materials must first go through numerous preparatory processes.
View Article and Find Full Text PDFAppl Biosaf
August 2025
Fraunhofer Institute for Cell Therapy and Immunology, Leipzig, Germany.
Background: Serum and other blood-derived products are widely used in biomedical and biopharmaceutical processes, especially for the production of vaccines or cell therapeutic applications. To ensure quality and safety, each serum lot undergoes testing for sterility to minimize the risk of disease transmission. A currently performed standard procedure is gamma-irradiation of serum for effectively killing pathogens.
View Article and Find Full Text PDFMed Phys
September 2025
Department of Radiation Oncology, Mayo Clinic in Florida, Jacksonville, Florida, USA.
Background: Dose-driven continuous scanning (DDCS) enhances the efficiency and precision of proton pencil beam delivery by reducing beam pauses inherent in discrete spot scanning (DSS). However, current DDCS optimization studies using traveling salesman problem (TSP) formulations often rely on fixed beam intensity and computationally expensive interpolation for move spot generation, limiting efficiency and methodological robustness.
Purpose: This study introduces a Break Spot-Guided (BSG) method, combined with two acceleration strategies-dose rate skipping and bounding-to optimize beam intensity while minimizing beam delivery time (BDT).
Med Phys
September 2025
Department of Medical Physics and Biomedical Engineering, University College London, London, UK.
Background: Integrated mode proton imaging is a clinically accessible method for proton radiographs (pRads), but its spatial resolution is limited by multiple Coulomb scattering (MCS). As the amplitude of MCS decreases with increasing particle charge, heavier ions such as carbon ions produce radiographs with better resolution (cRads). Improving image resolution of pRads may thus be achieved by transferring individual proton pencil beam images to the equivalent carbon ion data using a trained image translation network.
View Article and Find Full Text PDFJ Appl Clin Med Phys
September 2025
Department of Radiation Oncology, University of Utah, Salt Lake City, Utah, USA.
Purpose: The development of on-board cone-beam computed tomography (CBCT) has led to improved target localization and evaluation of patient anatomical change throughout the course of radiation therapy. HyperSight, a newly developed on-board CBCT platform by Varian, has been shown to improve image quality and HU fidelity relative to conventional CBCT. The purpose of this study is to benchmark the dose calculation accuracy of Varian's HyperSight cone-beam computed tomography (CBCT) on the Halcyon platform relative to fan-beam CT-based dose calculations and to perform end-to-end testing of HyperSight CBCT-only based treatment planning.
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