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This study reports the present status of our work on the hydrogen analysis of mineral and rock samples. The preparation of a standard material by means of ion implantation, a method of its calibration and the application of the method are described. The number of hydrogen atoms per unit volume in the standard material can be determined from the simultaneous observation of α-particles, γ rays and α–γ coincidence events for the 1H(19F,αγ) reaction at the 16.44 MeV resonance energy. The hydrogen content in a natural obsidian determined with the method mentioned above is in agreement with that obtained by FTIR. A heavy-ion microbeam system under construction, which consists of a Russian-type quadrupole magnet for beam focusing, a beam defining slit system and a γ-ray detector, is also described. [Copyright &y& Elsevier]

Background Gastrointestinal stromal tumor (GIST) is a type of mesenchymal tumor and has KIT mutations in 80–90% of the cases. The development of tyrosine kinase inhibitors have greatly improved patient outcomes. We have previously described association between lower pfetin (KCTD12) expression and poor prognosis in the GIST patients (Ref 1. Suenara Y et al. Clin Cancer Res2008). In this study, to investigate the protein profiles of kit expression, we performed comprehensive protein expression analysis using the gastric tumor cell lines and surgical specimens in GIST. Methods We performed KITgene knockdown using siRNA inthe GIST cell line (T1 cell line) and generated the protein expression profiling data by i-TRAQ. Based on this i-TRAQ protein profiling data from the T1 cell line, we referenced our previously published protein expression analysis databases associated with GIST prognosis in the patient samples (Ref 1.) and compared the protein profile of KIT-associated proteins (T1 cell line) and prognosis-associated protein (patient samples). Results In our study, the i-TRAQ profiling method detected expression of approximately 1500–2000 proteins. In KITknockdown cells, 125 proteins were identified to have statistically different expression (p < 0.05). Based on our previously published GIST prognosis protein profile database (using 17 patient tissue samples), 25 proteins were identified to be statistically significant (p < 0.05). Upon comparing the prognosis database with theKIT knockdown database, 6 proteins were identified as common proteins.In particular, the heat shock protein (HSP) 90-beta, which has been previously shown to contribute to the growth of cancer cells, was identified as a critical protein in the biological behavior of GIST. Conclusions HSP 90-beta is currently considered as a therapeutic target for HSP 90 inhibitors against imatinib-resistant GIST. Our data suggests that the differentiation and cell growth of GIST may be enhanced by the identified proteins, which are in turn induced by KIT. We believe that our established protein profile data will help in improving the understanding of malignant behaviors in GIST. Clinical trial identification HSP 90-betaplay an important role in the tumor progression of GISTs. Legal entity responsible for the study Juntendo University. Funding This study was supported by Grant-in-Aid from the Japan Society for the Promotion of Science (JSPS) KAKENHI (Grant Number #19K22694, #19H03789 and #15KK0353 to Y.S. ; #17K08730 to T.S.; #17K10987to K.K.; #19K16753 to K.A.; #18K15329 to T.O. , # 18K16634 to Y.K.) and Leading Advanced Projects for Medical Innovation (LEAP) (Grant Number # JP18am0001009) and the Practical Research for Innovative Cancer Control (Grant Number # JP18ck0106252) from the Japan Agency for Medical Research and Development. Disclosure All authors have declared no conflicts of interest. [ABSTRACT FROM AUTHOR]

We measured the yield of Auger electrons emitted through Coster–Kronig transitions from Rydberg states 1 s 2 p ( 3 P) nl (n = 7 , 8) and 1 s 2 2 p ( 2 P) nl (n = 5 , 6 , 7) of emergent atomic ions C q + under irradiation of 3.5-MeV/atom C+ and C 2 + ions on thin C foil targets. The Auger electron yields are suppressed for C 2 + irradiation compared with C+ irradiation and the relative yield becomes larger as n increases. Thus, amount of scattered electrons having lower relative energy in the projectile rest frame becomes larger. The results obtained in this study support the influence of projectile velocity on the cluster effect of secondary electron yields. [ABSTRACT FROM AUTHOR]

Abstract: The thermal neutron fluence that poured into the shielding concrete of proton accelerator facilities was estimated from the in situ production of 36Cl. The thermal neutron fluences at concrete surfaces during 10–30 years of operation were in the range of 1012–1014 n/cm2. The maxima in thermal neutron fluences were observed at ≈5–15cm in the depths analyzed for 36Cl/35Cl by AMS. These characteristics imply that thermalization of neutrons occurred inside the concrete. Compared to the several tens of MeV cyclotrons, secondary neutrons penetrate deeper into the concrete at the high-energy accelerators possessing acceleration energies of 400MeV and 12GeV. The attenuation length of neutrons reflects the energy spectra of secondary neutrons emitted by the nuclear reaction at the beam-loss points. Increasing the energy of secondary neutrons shifts the maximum in the thermal neutron fluences to deeper positions. The data obtained in this study will be useful for the radioactive waste management at accelerator facilities. [Copyright &y& Elsevier]

Abstract: We have measured the 36Cl/Cl ratio of uncultivated surface soil samples collected from 11 areas distributed throughout Japan to determine the undisturbed value of the ratio. The ratio was found to be on the order of 10−13 except for the Tokai-mura area, where four research reactors, two commercial nuclear power plants and a nuclear fuel reprocessing plant have been operated. The observed ratio in the Tokai-mura area was higher than 10−12. Notably, soil samples collected from a site of commercial BWR nuclear power plants in Fukushima prefecture showed no significant increase in 36Cl/Cl ratio. The 36Cl/Cl ratio depth profiles of soil samples collected at both of Makabe-town and Tokai-mura were also measured. Since Makabe-town is located about 50km apart from Tokai-mura, we do not expect it to be affected by the nuclear facilities. No large variations were observed in the Makabe depth profile; the measured ratios ranged from ∼3 to ∼5×10−13. The result obtained for Tokai-mura is significantly different in that from the surface to about 80cm depth, the measured ratios, ∼10−12, are much higher than any at Makabe. At depth below 80cm, the Tokai-mura ratios are lower and become indistinguishable from those at Makabe. The 36Cl/Cl ratio in unaffected areas of Japan is estimated to be 3–4×10−13. [Copyright &y& Elsevier]

Abstract: The mystery of 26Al origin has made the nuclide important in the astrophysics. It was proposed that the reaction, 14N(16O,α)26Al, may be one of the origin of the source of 26Al in the cosmic. In his work, the 26Al was measured with AMS by using full-stripping method, and the cross-sections of these reactions for around sub-barrier energies were deduced. The experiment details are described and the results represented. [Copyright &y& Elsevier]