153 research outputs found
Fundamental Considerations on Plasma Sprayed Ceramic Coating (Report II) : Structural Study of Plasma Sprayed Al₂O₃
Post-fission properties of uranium isotopes: a hybrid method with Langevin dynamics and the Hauser-Feshbach statistical model
Background: Precise understanding of nuclear fission is crucial for
experimental and theoretical nuclear physics, astrophysics, and industrial
applications; however, the complete physical mechanics is unresolved due to the
complexities. Purpose: In this study, we present a new method to describe the
dynamical-fission process and following prompt-neutron emission, where we
combine the dynamical fission calculation based on the Langevin method and the
Hauser-Feshbach statistical model. Methods: Two methods are connected smoothly
within the universal charge distribution and the energy conservation, allowing
us to calculate a sequence of fission dynamics and post-fission phase,
including prompt neutron emission. Results: Using a certain set of model
parameters, we successfully reproduce the experimental primary-fission yields,
total kinetic energy, independent-fission yields, and prompt neutron emissions
for the neutron induced fission of U, a compound nucleus of . We elucidate the physical mechanism of the characteristic
features observed in previous experiments, such as shell properties.
Additionally, we apply our calculation to two very neutron-rich uranium
isotopes, i.e., U and U, which are not experimentally
confirmed but are important for r-process nucleosynthesis. Theoretical results
indicate that U exhibits an asymmetric multiple-peak fission yield
distribution, while the neutron-rich U has a single peak due to
symmetric fission. Our method predicts post-neutron emission fragments, where
U shows a stronger neutron emissivity than U. Conclusions:
Our framework is highly reproducible in the experiments and shows that the
number of emitted neutrons after fission differs significantly in neutron-rich
uranium fission depending on distributions of fission variables.Comment: 12 pages, 11 figures, submitted to PRC, Comments are welcom
RNA interference suppression of mucin 5AC (MUC5AC) reduces the adhesive and invasive capacity of human pancreatic cancer cells
<p>Abstract</p> <p>Background</p> <p>MUC5AC is a secretory mucin normally expressed in the surface muconous cells of stomach and bronchial tract. It has been known that MUC5AC <it>de novo </it>expression occurred in the invasive ductal carcinoma and pancreatic intraepithelial neoplasm with no detectable expression in normal pancreas, however, its function remains uncertain. Here, we report the impact of MUC5AC on the adhesive and invasive ability of pancreatic cancer cells.</p> <p>Methods</p> <p>We used two MUC5AC expressing cell lines derived from human pancreatic cancer, SW1990 and BxPC3. Small-interfering (si) RNA directed against MUC5AC were used to assess the effects of MUC5AC on invasion and adhesion of pancreas cancer cells <it>in vitro </it>and <it>in vivo</it>. We compared parental cells (SW1990 and BxPC3) with MUC5AC suppressed cells by si RNA (si-SW1990 and si-BxPC3).</p> <p>Results</p> <p>MUC5AC was found to express in more than 80% of pancreatic ductal carcinoma specimens. Next we observed that both of si-SW1990 and si-BxPC3 showed significantly lower adhesion and invasion to extracellular matrix components compared with parental cell lines. Expression of genes associated with adhesion and invasion including several integerins, matrix metalloproteinase (MMP) -3 and vascular endothelial growth factor (VEGF) were down-regulated in both MUC5AC suppressed cells. Furthermore, production of VEGF and phosphorylation of VEGFR-1 were significantly reduced by MUC5AC down regulation. Both of si-SW1990 and si-BxPC3 attenuated activation of Erk1/2. <it>In vivo</it>, si-SW1990 did not establish subcutaneous tumor in nude mice.</p> <p>Conclusions</p> <p>Knockdown of MUC5AC reduced the ability of pancreatic cancer cells to adhesion and invasion, suggesting that MUC5AC might contribute to the invasive motility of pancreatic cancer cells by enhancing the expression of integrins, MMP-3, VEGF and activating Erk pathway.</p
Induction and prevention of virus-associated malignant lymphoma by serial transmission of EBV-related virus from cynomolgus by blood transfusion in rabbits.
Epstein-Barr virus (EBV)-related herpesvirus (Si-IIA-EBV) was serially transmitted for 3 passages from rabbit to rabbit of the opposite sex by blood transfusion, which subsequently induced virus-associated rabbit lymphomas. The virus could be transmitted by transfusion with 15-20 ml of whole blood (7/7) or irradiated blood (1/6) from the EBV-related virus-infected rabbits, but there was no transmission with transfusion of cell-free plasma (0/6) from the infected rabbits. Passive anti-EBV-VCA IgG (x 20 approximately x 10) titers decreased during the first 1-2 weeks in the transfused rabbits. The virus-transmitted rabbits showed a gradual increase in antibody titers ranging from peak titers of x 640 to x 2560 after 3 weeks of transfusion. The recipient origin of malignant lymphoma that developed in the first rabbit transfused by infected blood was confirmed by chromosomal analysis. This rabbit model thus shows that EBV-related herpesvirus is serially transmissible by blood transfusion and that transmission can not be completely prevented by irradiation of blood, but removal of blood cells is the best way to prevent transmission of EBV-related virus. Therefore, this animal model provides a convenient in vivo system for studies of the prevention and therapy of transfusion-related transmission of EBV and EBV-associated lymphoproliferative diseases in immunocompromised human beings.</p
Identification of 45 New Neutron-Rich Isotopes Produced by In-Flight Fission of a 238U Beam at 345 MeV/nucleon
A search for new isotopes using in-flight fission of a 345 MeV/nucleon 238U
beam has been carried out at the RI Beam Factory at the RIKEN Nishina Center.
Fission fragments were analyzed and identified by using the superconducting
in-flight separator BigRIPS. We observed 45 new neutron-rich isotopes: 71Mn,
73,74Fe, 76Co, 79Ni, 81,82Cu, 84,85Zn, 87Ga, 90Ge, 95Se, 98Br, 101Kr, 103Rb,
106,107Sr, 108,109Y, 111,112Zr, 114,115Nb, 115,116,117Mo, 119,120Tc,
121,122,123,124Ru, 123,124,125,126Rh, 127,128Pd, 133Cd, 138Sn, 140Sb, 143Te,
145I, 148Xe, and 152Ba
糖尿病患者における食事関連QOLの検討
Diet therapy constitutes the basis of treatment for diabetes mellitus. For its successful outcome, the patients' good compliance and persistence are essential. Thus, we have evaluated the diet-related quality of life (QOL) in diabetic patients to gain in
Urinary sodium-to-potassium ratio associates with hypertension and current disease activity in patients with rheumatoid arthritis: a cross-sectional study
BACKGROUND: Excessive salt intake is thought to exacerbate both development of hypertension and autoimmune diseases in animal models, but the clinical impact of excessive salt in rheumatoid arthritis (RA) patients is still unknown. We performed a cross-sectional study to clarify the associations between salt load index (urinary sodium-to-potassium ratio (Na/K ratio)), current disease activity, and hypertension in an RA population. METHODS: Three hundred thirty-six participants from our cohort database (KURAMA) were enrolled. We used the spot urine Na/K ratio as a simplified index of salt loading and used the 28-Joint RA Disease Activity Score (DAS28-ESR) as an indicator of current RA disease activity. Using these indicators, we evaluated statistical associations between urinary Na/K ratio, DAS28-ESR, and prevalence of hypertension. RESULTS: Urinary Na/K ratio was positively associated with measured systolic and diastolic blood pressure and also with prevalence of hypertension even after covariate adjustment (OR 1.34, p < 0.001). In addition, increased urinary Na/K ratio was significantly and positively correlated with DAS28-ESR in multiple regression analysis (estimate 0.12, p < 0.001), as was also the case in gender-separated and prednisolone-separated sub-analyses. CONCLUSION: Urinary Na/K ratio was independently associated with current disease activity as well as with prevalence of hypertension in RA patients. Thus, dietary modifications such as salt restriction and potassium supplementation should be investigated as a potential candidate for attenuating both disease activity and hypertension in RA patients
Associations between the orexin (hypocretin) receptor 2 gene polymorphism Val308Ile and nicotine dependence in genome-wide and subsequent association studies
Impact of the HCRTR2 gene risk variant on schizotypal personality traits (meanâÂąâSD). (DOC 54 kb
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