The purpose of the present study is to develop a methodology to evaluate fuel discharge through the CRGT (control-rod guide tube) during CDAs (core-disruptive accidents) of SFRs (sodium-cooled fast reactors), si...The purpose of the present study is to develop a methodology to evaluate fuel discharge through the CRGT (control-rod guide tube) during CDAs (core-disruptive accidents) of SFRs (sodium-cooled fast reactors), since fuel discharge will decrease the core reactivity and CRGTs have a potential to provide an effective discharge path. Fuel discharge contains multi-component fluid dynamics with phase changes, and, in the present study, the SFR safety analysis code SIMMER (Sn, implicit, multifield, multicomponent, Eulerian recriticality) was utilized as a technical basis. First, dominant phenomena affecting fuel discharge through the CRGT are identified based on parametric calculations by the SIMMER code. Next, validations on the code models closely relating to these phenomena were carried out based on experimental data. It was shown that the SIMMER code with some model modifications could reproduce the experimental results appropriately. Through the present study, the evaluation methodology for the molten-fuel discharge through the CRGT was successfully developed.展开更多
Based on calculations of the tidal Coulomb failure stress and investigations of the correlation between the Earth tide and the Ning'er earthquake sequence, the processes of fault nucleation and failure were simulated...Based on calculations of the tidal Coulomb failure stress and investigations of the correlation between the Earth tide and the Ning'er earthquake sequence, the processes of fault nucleation and failure were simulated. In these simulations we consider the influence of tidal stresses using the rate- and state-dependent friction laws. Furthermore, the effects on tidal trig- gering due to the stress amplitude and periodic oscillation properties were investigated, and the triggering effects between the tidal normal and tidal shear stresses were compared. The results showed that the Ning'er earthquake sequence was a physical consequence of tidal effects. A transition period To exists between the nucleation and failure processes of a seismic fault. When the period T of stress is equal to or becomes larger than To, the fault response becomes dependent on the periodic features of the loading stress; however, for T 〈 To, the response of the fault is nearly independent of the period. Both the tidal normal and tidal shear stresses have similar effect in the nucleation and failure processes; the clock changes generally increase with the maximum amplitudes of the tidal stresses. Tidal normal and tidal shear stresses with positive amplitudes mainly induce earth- quake triggering; however, the triggering effects induced by negative tidal stresses are smaller and faults are not sensitive to negative tidal stresses. Our results primarily reveal the physical mechanisms of tidal stress triggering.展开更多
Objective: To observe the effect of recombinant interleukin-6 (IL-6) and osteoprotegerin (OPG) on inhibiting bone absorption induced by receptor activa- tor for nuclear factor- rB ligand (RANKL) in murine osteo...Objective: To observe the effect of recombinant interleukin-6 (IL-6) and osteoprotegerin (OPG) on inhibiting bone absorption induced by receptor activa- tor for nuclear factor- rB ligand (RANKL) in murine osteo- clast precursor cells (OCPs) model. Methods: RAW 264.7 cells were solely treated with 50 ng/ml RANKL for 1 day, and then they were divided into three groups: RANKL (control group), RANKL+IL-6 (IL-6 group) and RANKL+IL-6+OPG (combination group). These cells were harvested and investigated by means of HE stain- ing under light microscope after consecutive 9 days. Furthermore, staining tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells were detected by in- verted phase contrast microscope. The absorption pits of bone slices were observed under scanning electron microscope. Results: The number of mature osteoclast cells in control group was more than that in IL-6 alone or IL-6 com- bined with OPG group (P〈0.05). Interestingly, this experi- ment has also demonstrated that there was a large number of TRAP-positive multinucleated osteoclasts (more than 3 nuclei) and several bone absorption formation in the con- trol group, whereas the outcome was completely different in both IL-6 group and IL-6+OPG group (P〈0.05). Conclusion: IL-6 can suppress the differentiation of mature osteoclasts as directly adding it into the RAW 264.7 cells induced by 50 ng/ml RANKL, and further the effect of osteolysis is remarkably reduced. When treatment with IL- 6 combined with OPG, a more effective strategy for the treat- ment of osteoporosis is reached.展开更多
Gastric carcinoma with osteoclast-like giant cells (OGCs) is an extremely rare tumor. So far, only six cases have been reported in the literature. Here we report an additional case of this tumor in a Chinese 78-year...Gastric carcinoma with osteoclast-like giant cells (OGCs) is an extremely rare tumor. So far, only six cases have been reported in the literature. Here we report an additional case of this tumor in a Chinese 78-year-old man presented with abdominal pain, vomiting, and hematemesis. Physical examination and gastroscopy revealed a tumor in the gastric antrum. The biopsy and pathological findings indicated a gastric adenocarcinoma with OGCs, which were present in both the tumor and the metastatic lymph nodes. Further immunohistochemical staining indicated that OGCs were reactive with CD68, CD45, and vimentin protein, but not with pancytokeratin, carcinoembryonic antigen, or epithelial membrane antigen, suggesting the monocytic/histiocytic derivation of these OGCs. In situ hybridization for Epstein-Burr virus showed no nuclear positivity in either adenocarcinoma or OGCs. Postoperative follow-up showed that the patient had survived for at least 6 months without recurrence. Further investigation is warranted to clearly define the prognostic significance of OGCs in gastric carcinoma.展开更多
The nuclear Chirality-Parity(ChP) violation, a simultaneous breaking of chiral and reflection symmetries in the intrinsic frame, is investigated with a reflection-asymmetric triaxial particle rotor model. A new symmet...The nuclear Chirality-Parity(ChP) violation, a simultaneous breaking of chiral and reflection symmetries in the intrinsic frame, is investigated with a reflection-asymmetric triaxial particle rotor model. A new symmetry for an ideal ChP violation system is found and the corresponding selection rules of the electromagnetic transitions are derived. The fingerprints for the ChP violation including the nearly degenerate quartet bands and the selection rules of the electromagnetic transitions are provided. These fingerprints are examined for ChP quartet bands by taking a two-j shell h11/2 and d5/2 with typical energy spacing for A = 130 nuclei.展开更多
文摘The purpose of the present study is to develop a methodology to evaluate fuel discharge through the CRGT (control-rod guide tube) during CDAs (core-disruptive accidents) of SFRs (sodium-cooled fast reactors), since fuel discharge will decrease the core reactivity and CRGTs have a potential to provide an effective discharge path. Fuel discharge contains multi-component fluid dynamics with phase changes, and, in the present study, the SFR safety analysis code SIMMER (Sn, implicit, multifield, multicomponent, Eulerian recriticality) was utilized as a technical basis. First, dominant phenomena affecting fuel discharge through the CRGT are identified based on parametric calculations by the SIMMER code. Next, validations on the code models closely relating to these phenomena were carried out based on experimental data. It was shown that the SIMMER code with some model modifications could reproduce the experimental results appropriately. Through the present study, the evaluation methodology for the molten-fuel discharge through the CRGT was successfully developed.
基金supported by the National Natural Science Foundation of China(Grant Nos.4110403641004021)+1 种基金Foundation of Provincial Education Department of Yunnan(Grant No.2014Z009)Foundation of School of Resources&Earth Science in Yunnan University(Grant No.2013CK002)
文摘Based on calculations of the tidal Coulomb failure stress and investigations of the correlation between the Earth tide and the Ning'er earthquake sequence, the processes of fault nucleation and failure were simulated. In these simulations we consider the influence of tidal stresses using the rate- and state-dependent friction laws. Furthermore, the effects on tidal trig- gering due to the stress amplitude and periodic oscillation properties were investigated, and the triggering effects between the tidal normal and tidal shear stresses were compared. The results showed that the Ning'er earthquake sequence was a physical consequence of tidal effects. A transition period To exists between the nucleation and failure processes of a seismic fault. When the period T of stress is equal to or becomes larger than To, the fault response becomes dependent on the periodic features of the loading stress; however, for T 〈 To, the response of the fault is nearly independent of the period. Both the tidal normal and tidal shear stresses have similar effect in the nucleation and failure processes; the clock changes generally increase with the maximum amplitudes of the tidal stresses. Tidal normal and tidal shear stresses with positive amplitudes mainly induce earth- quake triggering; however, the triggering effects induced by negative tidal stresses are smaller and faults are not sensitive to negative tidal stresses. Our results primarily reveal the physical mechanisms of tidal stress triggering.
文摘Objective: To observe the effect of recombinant interleukin-6 (IL-6) and osteoprotegerin (OPG) on inhibiting bone absorption induced by receptor activa- tor for nuclear factor- rB ligand (RANKL) in murine osteo- clast precursor cells (OCPs) model. Methods: RAW 264.7 cells were solely treated with 50 ng/ml RANKL for 1 day, and then they were divided into three groups: RANKL (control group), RANKL+IL-6 (IL-6 group) and RANKL+IL-6+OPG (combination group). These cells were harvested and investigated by means of HE stain- ing under light microscope after consecutive 9 days. Furthermore, staining tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells were detected by in- verted phase contrast microscope. The absorption pits of bone slices were observed under scanning electron microscope. Results: The number of mature osteoclast cells in control group was more than that in IL-6 alone or IL-6 com- bined with OPG group (P〈0.05). Interestingly, this experi- ment has also demonstrated that there was a large number of TRAP-positive multinucleated osteoclasts (more than 3 nuclei) and several bone absorption formation in the con- trol group, whereas the outcome was completely different in both IL-6 group and IL-6+OPG group (P〈0.05). Conclusion: IL-6 can suppress the differentiation of mature osteoclasts as directly adding it into the RAW 264.7 cells induced by 50 ng/ml RANKL, and further the effect of osteolysis is remarkably reduced. When treatment with IL- 6 combined with OPG, a more effective strategy for the treat- ment of osteoporosis is reached.
基金supported by the National Natural Science Foundation of China (Nos. 30200284, 30600278, and 30772359)the Program for New Century Excellent Talents in University (No. NCET-06-0641), China
文摘Gastric carcinoma with osteoclast-like giant cells (OGCs) is an extremely rare tumor. So far, only six cases have been reported in the literature. Here we report an additional case of this tumor in a Chinese 78-year-old man presented with abdominal pain, vomiting, and hematemesis. Physical examination and gastroscopy revealed a tumor in the gastric antrum. The biopsy and pathological findings indicated a gastric adenocarcinoma with OGCs, which were present in both the tumor and the metastatic lymph nodes. Further immunohistochemical staining indicated that OGCs were reactive with CD68, CD45, and vimentin protein, but not with pancytokeratin, carcinoembryonic antigen, or epithelial membrane antigen, suggesting the monocytic/histiocytic derivation of these OGCs. In situ hybridization for Epstein-Burr virus showed no nuclear positivity in either adenocarcinoma or OGCs. Postoperative follow-up showed that the patient had survived for at least 6 months without recurrence. Further investigation is warranted to clearly define the prognostic significance of OGCs in gastric carcinoma.
基金supported by the National Natural Science Foundation of China (11875075, 11935003, 11975031, and 11621131001)the National Key R&D Program of China (2018YFA0404400 and 2017YFE0116700)+1 种基金the State Key Laboratory of Nuclear Physics and Technology, Peking University (NPT2020ZZ01)the China Postdoctoral Science Foundation (2020M670014)。
文摘The nuclear Chirality-Parity(ChP) violation, a simultaneous breaking of chiral and reflection symmetries in the intrinsic frame, is investigated with a reflection-asymmetric triaxial particle rotor model. A new symmetry for an ideal ChP violation system is found and the corresponding selection rules of the electromagnetic transitions are derived. The fingerprints for the ChP violation including the nearly degenerate quartet bands and the selection rules of the electromagnetic transitions are provided. These fingerprints are examined for ChP quartet bands by taking a two-j shell h11/2 and d5/2 with typical energy spacing for A = 130 nuclei.