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  • 2025


    • Book : 33()
    • Pub. Date : 2025
    • Page : pp.100306-100306
    • Keyword :
  • 2025

    It is difficult to measure neutrons and gamma rays coming directly from uranium and plutonium atoms in pyroprocessed ingot, which is of great interest to nuclear safeguards. Most neutrons of the ingot are emitted from 244Cm isotope and gamma rays from its fission products. Therefore, it is necessary to identify spent fuel characteristics such as initial enrichment, burnup and cooling time from measurement and estimate plutonium mass from calibration curve or burnup calculations.In this study, we explored the possibility of characterizing pyroprocessed ingots using neutron and gamma-ray multiplicity counting. We particularly focused on finding the possible correlation between neutron and gammaray multiplicity properties (singles, doubles, and triples) and spent fuel properties for U/TRU/RE preprocessed ingot. We examined neutron and gamma-ray correlation for spent fuel, using the Cascading Gamma-ray Multiplicity with Fission (CGMF) and the Fission Reaction Event Yield Algorithm (FREYA) library in MCNP6.2. Due to high spontaneous fission rate, neutron and gamma-ray multiplicity parameters did not strongly correlate with multiplication factor from the point model but was proportional to 244Cm mass. The results based on the CGMF and FREYA fission library showed the similar trends for neutron and gamma-ray cases. The sum of two multiplicity data yielded best linearity with the 244Cm effective mass. Although total neutron counting (S) alone was sufficient for effectively characterizing spent fuel due to its strong linearity, this feasibility study confirmed that, in principle, it will be more effective to calculate the sum of neutron and gamma-ray multiplicity properties to directly estimate the mass of 244Cm, rather than relying on the conventional method of calculating the multiplication factor.
    • Book : 57(3)
    • Pub. Date : 2025
    • Page : pp.1-6
    • Keyword :
  • 2025

    Abstract Colorectal cancer (CRC) is the third most commonly diagnosed and leading cause of death worldwide. On the other hand, glioblastoma multiforme (GBM) is the most prevalent and aggressive primary malignant brain tumor in adults. Inherited diseases of DNA mismatch repair (MMR) can cause multiple cancers in the same patient including CRC and GBM. In this study, we report a 59-year-old woman presented with fatigue, constipation, abdominal distention, perianal pain, right-sided arm weakness, and personality changes. After investigations, it was diagnosed that sporadic metastatic CRC and GBM occurred simultaneously in the same patient, which was confirmed by colonoscopy, biopsy, imaging, and molecular testing. As the treatment of two cancers in the same patient is unique and complex, the absence of guidelines for such cases was discussed in a multidisciplinary tumor board including surgeons, medical, and radiation oncologists.
    • Book : 2025(2)
    • Pub. Date : 2025
    • Page :
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  • 2025

    The paper considers the results of experiments on localization of the sources of geoacoustic radiation generated in near-surface sedimentary rocks. Geoacoustic signals from sources were recorded by a spaced sensor system consisting of two combined receivers and a hydrophone. The system was installed near the bottom of a natural water body (Mikizha lake) in Kamchatka. Radiation sources were located by two methods, a triangulation survey and estimation of the signal arrival time difference from spaced receivers. Coordinates for more than 40 sources were measured, and their space distribution was mapped. As the result of the experiment, it was stated that geoacoustic radiation sources are located in bottom rocks at the depths up to 2.20 ± 0.25 m at the distances of up to 8 ± 0.25 m. Localization of geoacoustic radiation sources is topical for projecting a new alarm system for the notification on the possibility of strong earthquake occurrence. The results of the analysis of the frequency of rock AE source generation and accurate estimation of their location will be the basis of this system.
    • Book : 25(4)
    • Pub. Date : 2025
    • Page : pp.1197-1197
    • Keyword :
  • 2025


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


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  • 2025


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

    Psilocin, the active metabolite of psilocybin, is a psychedelic and agonist at the serotonin 2A receptor (5-HT2AR) that has shown positive therapeutic effects for brain disorders such as depression. To elucidate the brain effects of psilocybin, we directly compared the acute effects of 5-HT2AR agonist (psilocybin) and antagonist (ketanserin) on cerebral blood flow (CBF) using pseudo-continuous arterial spin labeling magnetic resonance imaging (MRI) in a single-blind, cross-over study in 28 healthy participants. We evaluated associations between plasma psilocin level (PPL) or subjective drug intensity (SDI) and CBF. We also evaluated drug effects on internal carotid artery (ICA) diameter using time-of-flight MRI angiography. PPL and SDI were significantly negatively associated with regional and global CBF (∼11.6% at peak drug effect, p < 0.0001). CBF did not significantly change following ketanserin (2.3%, p = 0.35). Psilocybin induced a significantly greater decrease in CBF compared to ketanserin in the parietal cortex (pFWER < 0.0001). ICA diameter was significantly decreased following psilocybin (10.5%, p < 0.0001) but not ketanserin (−0.02%, p = 0.99). Our data support an asymmetric 5-HT2AR modulatory effect on CBF and provide the first in vivo human evidence that psilocybin constricts the ICA, which has important implications for understanding the neurophysiological mechanisms underlying its acute effects.
    • Book : ()
    • Pub. Date : 2025
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  • 2025


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    • Pub. Date : 2025
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