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• Pub. Date : 2025
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• Pub. Date : 2025
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Abstract Background Medulloblastoma is the most common malignant pediatric brain tumor, typically treated with normofractionated craniospinal irradiation (CSI) with an additional boost over about 6 weeks in children older than 3 years. This study investigates the sensitivity of pediatric medulloblastoma cell lines to different radiation fractionation schedules. While extensively studied in adult tumors, these ratios remain unknown in pediatric cases due to the rarity of the disease. Materials and methods Five distinct medulloblastoma cell lines (ONS76, UW228-3, DAOY, D283, D425) were exposed to varying radiation doses and fractionation schemes. In addition, ONS76 and UW228-3 stably overexpressing MYC were analyzed. Alpha/beta values, representing fractionation sensitivity, were quantified using the linear-quadratic model of radiation survival. Results The study unveiled elevated alpha/beta ratios across diverse medulloblastoma cell lines, with a weighted mean alpha/beta value of 11.01 Gy (CI: 5.23–16.79 Gy). Neither TP53 status nor the levels of MYC expression influenced fractionated radiosensitivity. Furthermore, differences in alpha/beta values cannot be correlated with molecular subgroups (p = 0.07) or radiosensitivity (SF2). Conclusion These in vitro findings strongly recommend normofractionated or hyperfractionated radiotherapy for paediatric medulloblastoma cases due to consistently high alpha/beta values across subgroups. Conversely, hypofractionated radiotherapy is not advisable within a curative approach. This study presents significant potential by enabling the estimation of radiobiological fractionations and dose effects in young, vulnerable patients, highlighting its importance for advancing patient-specific therapeutic strategies.

• Book : 20(1)
• Pub. Date : 2025
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• Pub. Date : 2025
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AbstractNasopharyngeal carcinoma (NPC) is an Asia‐prevalent malignancy, yet its genetic underpinnings remain incompletely understood. Here, a transcriptome‐wide association study (TWAS) is conducted on NPC, leveraging gene expression prediction models based on epithelial tissues and genome‐wide association study (GWAS) summary statistics from 1577 NPC cases and 6359 controls of southern Chinese descent. The TWAS identifies VAMP8 on chromosome 2p11.2 as a novel susceptibility gene for NPC. Further fine‐mapping analyses pinpoint rs1058588, located within VAMP8, as a causal variant through eQTL colocalization, and GWAS analyses across multiple cohorts, achieving GWAS significance (OR = 1.18, P = 3.09 × 10−10). Functional assays demonstrate that VAMP8 exerts a tumorigenic role in NPC, enhancing cell proliferation, migration, and tumor growth. Mechanically, it is uncovered that rs1058588 modulates VAMP8 expression by altering its binding affinity to miR‐185. Furthermore, the results show that VAMP8 interacts with DHX9 to facilitate the nuclear recruitment of p65, activating the NF‐κB pathway. Collectively, the findings shed light on the genetic predisposition to NPC and underscore the critical role of the functional axis involving miR‐185, VAMP8, DHX9, and the NF‐κB pathway in NPC pathogenesis.

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• Pub. Date : 2025
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We study the diffusion of heavy quarks in the early stage of highenergy nuclear collisions. The pre-equilibrium stage of relativistic heavy-ion collisions, commonly known as Glasma, evolves according to the classical Yang-Mills equations. Heavy quarks are coupled to the evolving Glasma fields via relativistic kinetic theory. We compute the momentum broadening, σp as well as the angular momentum fluctuations of heavy quarks in the early stage, which turn out to be anisotropic due to the anisotropy of the background gluon fields. We observe that σp ∝ t2 at very initial times. This non-Markovian diffusion of heavy quarks in the early stages is explained by the memory effect present in the gluon fields.

• Book : 316()
• Pub. Date : 2025
• Page : pp.02002-02002
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In alignment with China’s “carbon peak and carbon neutrality” goals, carbon reduction and energy structure transformation are central priorities. As a major emitter, the power industry plays a key role in this transition, and identifying effective pathways for its green energy transformation is essential to driving broader industrial green transformation and ensuring sustainable development. This article calculates the elasticity of substitution between clean and non-clean energy within China’s power sector from 1993 to 2021, employing the kernel density estimation method. By further comparing the goodness-of-fit across various nested structures of clean energy sources, the study identifies the optimal internal nested structure and examines the interactions among its components. The results underscore two key insights: on the one hand, a robust substitutive relationship exists between clean and non-clean energy, with the substitution elasticity of 1.646, exhibiting pronounced regional heterogeneity characterized as “weaker in the east and stronger in the west”; on the other hand, the optimal nested structure of clean energy is identified as (hydropower + nuclear power)—wind power—solar power. In this structure, the elements display a substitutive relationship in the Eastern Region, while in the Western Region, they exhibit a complementary relationship.

• Book : 17(3)
• Pub. Date : 2025
• Page : pp.1098-1098
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• Pub. Date : 2025
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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.

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• Pub. Date : 2025
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• Book : ()
• Pub. Date : 2025
• Page : pp.1-9
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