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2025
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2025
AbstractBackgroundPatient‐specific quality assurance (PSQA) is a crucial yet resource‐intensive task in proton therapy, requiring special equipment, expertise and additional beam time. Machine delivery log files contain information about energy, position and monitor units (MU) of all delivered spots, allowing a reconstruction of the applied dose. This raises the prospect of phantomless, log file‐based QA (LFQA) as an automated replacement of current phantom‐based solutions, provided that such an approach guarantees a comparable level of safety.PurposeTo retrieve a reliable LFQA conclusion from a one‐time plan delivery before treatment initiation, deviations between planned and logged parameters must either be persistent over all following treatment fractions or, in case of random fluctuations, must not have a relevant impact on the reconstructed dose distribution. We therefore investigated the reproducibility of log file parameters over multiple patient treatment fractions and compared the reconstructed dose distributions.MethodsLog file variability was examined at both spot parameter and integral dose levels. The log files of 14 patient treatment plans were analyzed retrospectively for a total of 339 delivered fractions. From the recorded x/y position and MU parameters per spot, the respective mean difference to the planned value (accuracy) and the standard deviation (reproducibility) were calculated for 108,610 planned spots. The dose distributions reconstructed from the log files of each fraction were evaluated against the planned fraction dose using 3D gamma index analysis. The dose‐based gamma pass rate was correlated with a new spot‐based log file pass rate . Beam timing information from the log files was used to quantify the total plan/field delivery time stability after excluding machine interlocks.ResultsThe mean spot‐wise accuracy with respect to distance from planned positions and MUs was (0.6 ± 0.3) mm and (0.0001 ± 0.0023) MU, respectively. The mean reproducibility of the observed single spot deviations was (0.2 ± 0.1) mm and (0.0004 ± 0.0004) MU (mean ± standard deviation). These variations resulted in minimal changes in the reconstructed fraction dose with (2 mm/2%) > 99% for all studied fractions. Results for more sensitive criteria (1 mm/1%) were plan‐specific, but on average > 92.6% per plan and correlated with (1 mm) pass rates (0.51 ≤ rPearson ≤ 0.99). Field delivery times were reproducible within ± 4 s (2σ) and no treatment interruptions were observed in 92.8% of cases.ConclusionsThe log file records of plan‐relevant spot parameters are well‐reproducible over multiple fractions and deviations have no dosimetrically relevant impact on the reconstructed fraction doses. Results of a one‐time pre‐treatment LFQA are considered as valid for the entire treatment course and there is no concern in this regard to replace state‐of‐the‐art phantom measurements in the current PSQA workflow.- Book : ()
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2025
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2025
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- Page : pp.101726-101726
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2025
Mung bean (Vigna radiata) plays a significant role in agricultural trade, food processing and utilization, and cropping structure adjustment due to its abundant nutritional components, medicine-food homology, capacity for nitrogen fixation, and soil improvement. The low yield level is a crucial limitation factor in the mung bean industry, while heterosis is an efficient path for increasing crop yields. The flexible utilization of male sterile mung bean materials may solve this pressing demand in the industry. This study identified a completely male-sterile mutant, vrnp 1, in the EMS-mutagenized mung bean cultivar Jilv 10 population, which is controlled by a single recessive nuclear gene. Furthermore, we employed a series of microscopical and histological techniques and observed that the tapetal cells in the vrnp 1 mutant did not perform as expected when reaching stage 8 of anther development, notably exhibiting a delay in entering PCD. This was accompanied by a failure to deposit cell wall components onto the pollen wall, culminating in a complete absence of mature pollen and the manifestation of male sterility. In conclusion, the vrnp 1 mutant could potentially serve as a promising candidate for male sterility in exploiting hybrid vigor in mung bean. Our research may elucidate how the delayed initiation of programmed cell death in tapetal cells contributes to a factor implicated in mung bean male sterility. Furthermore, the phenotypic data collected during pivotal developmental phases may have contributed to a better grasp of mung bean microspores and anther development.- Book : 15(2)
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- Page : pp.312-312
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2025
Muon tomography is a consolidated technique to investigate the internal components of high-opacity objects. With the use of detectors with high angular and spatial resolution (usually referred to as “muon telescopes”), the track reconstruction of the atmospheric muons after they have crossed the object provides muography images, also called “muon radiographs.” This work presents the muography (or muon radiography) reconstruction of a French historical UNGG (natural-uranium, graphite, and gas) nuclear reactor: the G3 reactor, located at CEA Marcoule. A measurement campaign involving 46 points of view below the reactor was conducted, providing a set of muography images. The method to analyze these muographies is detailed here. Besides, a method to combine these images to provide three-dimensional (2D) tomography of the reactor is also presented. After a general description of the project, all the methods performed to reconstruct and analyze muographies and the 3D reconstruction are presented. It comprises different tools based on data augmentation and machine learning, which proved to be very efficient on simulated data and increase the quality of the experimental data analysis. All these methods were evaluated with a set of synthetic data, providing a precise evaluation for better identification of the associated systematics. Finally, all the described methods were applied to the experimental data, leading to a full characterization of the reactor, in both two dimensions and three dimensions, and the identification of some discrepancies between the reactor actual structure and the original model. These anomalies are discussed, showing the potential of the technique to evaluate the internal structure of a nuclear reactor. This could have potential applications during the decommissioning phase and the dismantling phase of different kinds of nuclear installation.
Published by the American Physical Society
2025
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2025
ABSTRACT
Interlinked interactions between the viral capsid (CA), nucleoporins (Nups), and the antiviral protein myxovirus resistance 2 (MX2/MXB) influence human immunodeficiency virus 1 (HIV-1) nuclear entry and the outcome of infection. Although RANBP2/NUP358 has been repeatedly identified as a critical player in HIV-1 nuclear import and MX2 activity, the mechanism by which RANBP2 facilitates HIV-1 infection is not well understood. To explore the interactions between MX2, the viral CA, and RANBP2, we utilized CRISPR-Cas9 to generate cell lines expressing RANBP2 from its endogenous locus but lacking the C-terminal cyclophilin (Cyp) homology domain and found that both HIV-1 and HIV-2 infections were reduced significantly in RANBP2
ΔCyp
cells. Importantly, although MX2 still localized to the nuclear pore complex in RANBP2
ΔCyp
cells, antiviral activity against HIV-1 was decreased. By generating cells expressing specific point mutations in the RANBP2-Cyp domain, we determined that the effect of the RANBP2-Cyp domain on MX2 anti-HIV-1 activity is due to direct interactions between RANBP2 and CA. We further determined that CypA and RANBP2-Cyp have similar effects on HIV-1 integration targeting. Finally, we found that the Nup requirements for HIV infection and MX2 activity were altered in cells lacking the RANBP2-Cyp domain. These findings demonstrate that the RANBP2-Cyp domain affects viral infection and MX2 sensitivity by altering CA-specific interactions with cellular factors that affect nuclear import and integration targeting.
IMPORTANCE
Human immunodeficiency virus 1 (HIV-1) entry into the nucleus is an essential step in viral replication that involves complex interactions between the viral capsid (CA) and multiple cellular proteins, including nucleoporins (Nups) such as RANBP2. Nups also mediate the function of the antiviral protein myxovirus resistance 2 (MX2); however, determining the precise role of Nups in HIV infection has proved challenging due to the complex nature of the nuclear pore complex (NPC) and significant pleiotropic effects elicited by Nup depletion. We have used precise gene editing to assess the role of the cyclophilin domain of RANBP2 in HIV-1 infection and MX2 activity. We find that this domain affects viral infection, nucleoporin requirements, MX2 sensitivity, and integration targeting in a CA-specific manner, providing detailed insights into how RANBP2 contributes to HIV-1 infection.
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2025
Glycogen storage diseases (GSDs) are rare, inherited disorders of glycogen metabolism caused by a deficiency of enzymes or transporters. GSDs involve the liver, kidneys, skeletal muscles, and heart of children and young adults. The complications involving these organs affect the prognosis of patients with GSDs. Magnetic resonance imaging (MRI) is useful for identifying the complications of GSDs and monitoring the response to treatments owing to its ability of tissue characterization and lack of need for ionizing radiation. This pictorial review describes the MRI sequences used for GSDs, presents clinical examples, and emphasizes the pivotal role of MRI as an imaging tool in diagnosing complications associated with GSDs. Further MRI sequences that can be used to quantify the severity of GSDs are discussed.- Book : ()
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2025
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