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Abstract: Reaction rate experiments on the accelerator-driven system (ADS) are conducted by combining a critical assembly of a solid-moderated and -reflected core with a pulsed neutron generator. Neutrons (14MeV) generated from the accelerator are injected into a subcritical system and the reaction rates are measured by the foil activation method to obtain neutronic spectrum data. The numerical calculations are executed by MCNPX with ENDF/B-VI.8, JENDL-3.3 and JENDL/D-99 libraries to evaluate the reaction rates of activation foils set in the center of the core. For the ADS experiments with 14MeV neutrons, the C/E values between the experiments and the calculations are found to be well within the relative difference of about 30% in all foils up to subcriticality 1.05%Δk/k. The reaction rates do not depend on the subcriticality level in cases of 115In, 56Fe (purity 99.99%), 27Al, whereas subcriticality dependence is observed in 93Nb. In the critical experiments carried out in the A, B and C cores, special mention should be made of the remarkable effect of the composition rate of 56Fe material. Thus a remarkable improvement is observed in the accuracy of experimental and numerical reaction rates, demonstrating the importance of material impurity for subcritical experiments. [Copyright &y& Elsevier]

Background: The attainment of drug resistance in gastric cancer (GC) is a problematic issue. Although many studies have shown that cancer stem cells (CSCs) play an important role in the acquisition of drug resistance, there is no clinically available biomarker for predicting oxaliplatin (L-OHP) resistance in relation to CSCs. Organoid technology, a novel 3D cell culture system, allows harboring of patient-derived cancer cells containing abundant CSCs using niche factors in a dish., Methods: In this study, we established L-OHP-resistant gastric cancer organoids (GCOs) and evaluated their gene expression profile using microarray analysis. We validated the upregulated genes in the L-OHP-resistant GCOs compared to their parental GCOs to find a gene responsible for L-OHP resistance by qRT-PCR, immunohistochemistry, in vitro, and in vivo experiments., Results: We found myoferlin (MYOF) to be a candidate gene through microarray analysis. The results from cell viability assays and qRT-PCR showed that high expression of MYOF correlated significantly with the IC50 of L-OHP in GCOs. Immunohistochemistry of MYOF in GC tissue samples revealed that high expression of MYOF was significantly associated with poor prognosis, T grade, N grade, and lymphatic invasion, and showed MYOF to be an independent prognostic indicator, especially in the GC patients treated with platinum-based chemotherapy. The knockdown of MYOF repressed L-OHP resistance, cell growth, stem cell features, migration, invasion, and in vivo tumor growth., Conclusions: Our results suggest that MYOF is highly involved in L-OHP resistance and tumor progression in GC. MYOF could be a promising biomarker and therapeutic target for L-OHP-resistant GC cases., (© 2021. The International Gastric Cancer Association and The Japanese Gastric Cancer Association.)