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  • 2025

    Abstract This study carried out a critical review of the principles of radioprotection, including the ALARA, ALADA, and ALADAIP principles. The Google Scholar and PubMed databases were the search resources, and the following keywords were searched: Linear No-Threshold (LNT); Biologic Effects of Ionizing Radiation (BEIR VII); As Low As Reasonably Achievable (ALARA); As Low As Diagnostically Acceptable (ALADA); As Low As Diagnostically Acceptable, being Indication-oriented and Patient-specific (ALADAIP). This critical review included studies with historical references, reviews, position papers, and clinical and experimental studies. Regarding data extraction, only original articles were selected after the screening process. Much of the current evolution of X-ray machines and radioprotection protocols has stemmed from legitimate concerns about this topic. This development has grown out of the relevant work of organizations like ICRP, UNSCEAR, and other renowned international organizations. Low doses of radiation, such as those used for diagnosis, also occur naturally and are present in everyday life. Although there is no agreement on the actual risk involving low doses, the recommendations of ALARA, ALADA, and ALADAIP prevail, in line with the trend to uphold principles that balance the importance of X-ray diagnostic imaging with the intention of keeping the doses as low as possible. The benefits of X-ray exams, when justified, tend to outweigh the low risks attributed to them.
    • Book : 39()
    • Pub. Date : 2025
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  • 2025

    In this study, we tested the overall hypothesis that CC expansion and early embryo development would be improved by including follicular fluid (FF) from small or large follicles in the oocyte maturation medium. In the first experiment, FF aspirated from bovine abattoir ovaries was added to the maturation medium at 0, 25, 50, 75 or 100%. Images of individual COCs were captured at 0, 6, 12 and 19 hours (h) of the maturation period and analyzed to calculate change in the total area over time. Cumulus cell expansion was greatest in COCs matured in 75% and 50% FF, and these differences were detectable at 12 (75% FF only) and 19 h (50% and 75% FF) of maturation. The improvement in CC expansion was greatest when FF from small follicles was used. Treatments for the subsequent experiments were selected based upon the results of the first experiment. Oocyte nuclear maturation rates were observed after supplementing the maturation medium with 0 or 75% FF and maturing for 19 h. The rate of nuclear maturation as determined by the presence or absence of the first polar body was similar between control (0% FF) and treated (75% FF) groups. In the final experiment, COCs were matured in 0%, 50% or 75% FF in preparation for IVF. Duration of the maturation period (12, 19 or 22 h) and size of the follicles from which FF was collected (small or large) also varied. In general, FF supplementation at 50% did not affect the zygotes’ developmental potential (neither increased nor decreased). Supplementation of maturation medium with 75% FF from small follicles consistently reduced measures of embryo development while 75% FF from large follicles yielded mixed results. It is concluded that FF supplementation improves CC expansion, but the greater CC expansion does not benefit subsequent embryo development. Notably, however, the 50% FF treatment did not reduce blastocyst rates, indicating that FF can be included in maturation media at concentrations of 50% or less with no detriment to IVF outcomes.
    • Book : 20(2)
    • Pub. Date : 2025
    • Page : pp.e0318376-e0318376
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  • 2025

    Oxide-dispersion-strengthened (ODS) alloys exhibit exceptional mechanical properties, making them ideal for high-temperature applications in areas such as aerospace and nuclear reactors. The traditional manufacturing of ODS alloys involves mechanical alloying, followed by processes such as hot extrusion and hot isostatic pressing. However, these methods are limited when it comes to producing complex geometries. Recent advances in additive manufacturing (AM) techniques, specifically selective laser melting (SLM) and directed-energy deposition (DED), offer exciting new possibilities for fabricating ODS alloys. Early research demonstrated the feasibility of using SLM to create complex parts with uniformly dispersed oxide particles, thereby enhancing the materials’ properties. Subsequent studies confirmed that optimising the SLM parameters could further improve the mechanical performance of ODS alloys. DED techniques have also shown promise, with innovations like in-situ oxide formation during deposition and high-speed laser cladding. These methods have achieved success by producing ODS materials with refined microstructures and enhanced mechanical properties. The latest research continues to explore the potential of AM for ODS alloys, focusing on improving the dispersion of nanoparticles and minimising the tendency of particles to agglomerate. Overall, AM has advanced the fabrication of ODS alloys by offering efficient production routes and the ability to create intricate designs with superior properties.
    • Book : 59(1)
    • Pub. Date : 2025
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  • 2025


    • Book : ()
    • Pub. Date : 2025
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  • 2025


    • Book : ()
    • Pub. Date : 2025
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  • 2025

    Abstract Methanol is one of the most abundant complex organic molecules in interstellar environments. Molecular lines of its rare isotopologues 12CH3 17OH and 12CH3 18OH therefore play a crucial role in examining the column density of 12CH3 16OH, which serves as a reference for organic molecular chemistry in interstellar clouds. In this study, we have recorded the spectroscopic emission spectrum of 12CH3 17OH in the frequency range between 216 and 264 GHz by making use of an emission-type millimeter and submillimeter spectrometer. We have specifically paid attention to the Q-branch transitions, which are the strongest line series in this frequency region. Among the stable oxygen isotopes, 16O, 17O, and 18O of methanol, only 12CH3 17OH obviously shows line profiles having double and/or triple peaks in low-J transitions, due to the nuclear quadrupole interaction. The newly obtained 12CH3 17OH data will play an important role in facilitating a deeper understanding of the organic chemistry related to star and planet formation. The 12CH3 17OH line data allow us to trace and constrain the isotopic ratio 17O/18O in methanol, which is efficient to investigate the galactic-scale evolution of elements. In addition, we also assigned some transitions of 13CH3 17OH in the recorded spectrum.
    • Book : 980(1)
    • Pub. Date : 2025
    • Page : pp.110-110
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  • 2025


    • Book : ()
    • Pub. Date : 2025
    • Page : pp.1-16
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  • 2025

    Prostate cancer is a leading cause of cancer-related mortality in men, with radiotherapy (RT) playing a pivotal role in treatment. However, reliable biomarkers for assessing relapse risk following RT remain scarce. This study aimed to evaluate circulating epithelial tumor cells (CETC/CTC) as potential biomarkers for assessing relapse risk in prostate cancer patients undergoing RT. Peripheral blood samples were collected from 52 prostate cancer patients, and CETC/CTC were detected using the EpCAM surface marker. Patients received definitive, adjuvant, or salvage RT, and CETC/CTC counts were measured before, at mid-treatment, and at the end of RT. The association between changes in CETC/CTC counts and relapse risk was examined. CETC/CTC were detected in 96% of patients prior to RT. A significant reduction in CETC/CTC counts during RT, particularly in patients who had undergone surgery, was associated with a lower relapse risk. In contrast, an increase in CETC/CTC counts during or after RT was associated with a higher relapse risk (hazard ratio = 8.8; p = 0.002). Furthermore, 36% of patients receiving adjuvant RT and 14% of those receiving definitive RT relapsed, with a higher risk observed in patients showing increasing CETC/CTC counts during RT. Among patients receiving salvage RT, 18% relapsed, though changes in CETC/CTC counts were less significantly associated with relapse. Monitoring CETC/CTC levels during RT offers important prognostic insights into relapse risk in prostate cancer patients. While changes in CETC/CTC counts correlated with relapse, PSA levels measured during the study did not reliably reflect relapse risk in this cohort. CETC/CTC shows promise as a prognostic marker, though further studies are required to validate its clinical superiority over PSA.
    • Book : 26(4)
    • Pub. Date : 2025
    • Page : pp.1548-1548
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  • 2025

    Dissociation upon sulfur K-shell excitation or ionization of SF6 is studied by sulfur L-shell emission spectroscopy using synchrotron radiation and multiconfiguration Dirac-Hartree-Fock calculations of emission energies and transition rates. The decay path involves in particular Auger emission with the ejection of one or more electrons, leading to singly or multiply charged intermediate states. Nevertheless, the results of the study show that the observed photon emission at 151–152 eV following excitation at 2485–2489 eV originates dominantly from transitions in neutral sulfur. This clearly indicates that the central atom retains its electrons in a dissociation process where all fluorine atoms detach before the S 2p decay. Published by the American Physical Society 2025
    • Book : 134(6)
    • Pub. Date : 2025
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  • 2025

    AbstractIt is known that ultrasound-targeted microbubble cavitation (UTMC) can induce vasodilation. This image guided spatially targeted approach is called provascular therapy when used as a radiotherapy sensitizer in radiation oncology. Extracellular adenosine-5’-triphosphate (eATP), which plays an important role in vascular tone regulation, is released by cells following UTMC, possibly through sonoporation (formation of temporary and non-deadly pores in the cell membrane) and/or cell death. Herein, we were interested in quantifying UTMC-mediated ATP releasedin vitrousing a microfluidics-based model and study its relationship with UTMC-mediated cell fate to better understand and improve UTMC mediated bioeffects.Lipid microbubbles (MB, Definity®), luciferin-luciferase (LL – for eATP quantification), and propidium iodide (PI – poration tracer) were flown over HUVEC cells cultured in a microfluidic device. Ultrasounds at 1 MHz, varying in pressure (300, 400 kPa) and length (10, 100, 1000 cycles) were applied to the chip. The LL chemiluminescent signal after the ultrasound pulse was acquired with an EMCCD camera to characterize ATP release kinetics. Then, a viability assay was performed with calcein-AM. An in-house MATLAB program pairing eATP kinetics with PI/calcein data was used to classify cells into three categories (sonoporated, dead, and untreated).Within the testing conditions, a single UTMC pulse caused between 4% and 55% PI-positive (PI+) cells in the ultrasound-treated area. Amongst PI+ cells, we generally found more dead cells than sonoporated cells, except for milder pulses (300 kPa; 10 and 100 cycles). The analysis of individual responses of ATP release demonstrated that dead cells released more ATP (up to 22.4 ± 12.2 fmol/cell) than sonoporated cells (6.8 ± 3.4 fmol/cell) and at a faster release rate which peaked at 4s.This study showed that sonoporation plays a significant role in UTMC-mediated ATP release, advancing our understanding of UTMC’s potential use as a radiosensitizer in solid tumors.
    • Book : ()
    • Pub. Date : 2025
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