A novel double 1：11 series arsenotungstate, [Cu^I（phen）2]5H6[Sm（AsW11O39）2]·6H2O （phen=1, 10-phenanthroline） was synthesized by the hydrothermal method and characterized by elemental analysis, 1R spectra, ...A novel double 1：11 series arsenotungstate, [Cu^I（phen）2]5H6[Sm（AsW11O39）2]·6H2O （phen=1, 10-phenanthroline） was synthesized by the hydrothermal method and characterized by elemental analysis, 1R spectra, and single-crystal X-ray diffraction. The title compound was monoclinic, space group P2 1/c, a=3.75710（2） nm, b=1.39776（8） nm, c=-3.33735（18） nm, β=96.967（10）°, V=17.3969（17） nm^3, Z=4. Single crystal X-ray structural analyses revealed that the dimeric polyanion, [SmAs2W22O78]^1-, consisted of one central Sm^3＋ ion and two tetradentate heteropoly ligands [ASW11O39]^7-. The Sm^3＋ ion and two tetradentate defective [AsW11O39]^7- anions were joined together by the sharing of four oxygen atoms from each heteropoly ligand. The bond valence sum （BVS） calculations of the title compound suggested that all four Cu atoms were in the ＋1 oxidation sate.展开更多
Motivated by recent advances made in the study of dividend control and risk management problems involving the U.S.bankruptcy code,in this paper we follow[44]to revisit the De Finetti dividend control problem under the...Motivated by recent advances made in the study of dividend control and risk management problems involving the U.S.bankruptcy code,in this paper we follow[44]to revisit the De Finetti dividend control problem under the reorganization process and the regulator's intervention documented in U.S.Chapter 11 bankruptcy.We do this by further accommodating the fixed transaction costs on dividends to imitate the real-world procedure of dividend payments.Incorporating the fixed transaction costs transforms the targeting optimal dividend problem into an impulse control problem rather than a singular control problem,and hence computations and proofs that are distinct from[44]are needed.To account for the financial stress that is due to the more subtle concept of Chapter 11 bankruptcy,the surplus process after dividends is driven by a piece-wise spectrally negative Lévy process with endogenous regime switching.Some explicit expressions of the expected net present values under a double barrier dividend strategy,new to the literature,are established in terms of scale functions.With the help of these expressions,we are able to characterize the optimal strategy among the set of admissible double barrier dividend strategies.When the tail of the Lévy measure is log-convex,this optimal double barrier dividend strategy is then verified as the optimal dividend strategy,solving our optimal impulse control problem.展开更多
AIM:To explore mutations in serine/threonine kinase 11(STK11) gene in Peutz-Jeghers syndrome(PJS) with gastrointestinal(GI) hamartomatous polyps.METHODS:Six Japanese PJS patients in 3 families were enrolled in this st...AIM:To explore mutations in serine/threonine kinase 11(STK11) gene in Peutz-Jeghers syndrome(PJS) with gastrointestinal(GI) hamartomatous polyps.METHODS:Six Japanese PJS patients in 3 families were enrolled in this study.Each of the cases had hamartomatous polyposis in the gastrointestinal tract,including the small intestine,along with mucocutaneous hyperpigmentation.Narrow-band imaging(NBI)-magnification endoscopy was employed to detect microvascular and microsurface irregularities in the GI lesions.NBI magnification findings could be classified into three groups(type A,type B,or type C).Endoscopic polypectomy was performed using double-balloon enteroscopy or colonoscopy.Genomic DNA was extracted from a whole blood sample from each subject.All of the coding exons of STK11 gene,its boundary regions,and the promoter region containing the polymorphic regions were amplified by polymerase chain reaction,and direct sequencing was performed to assess the germline mutations.RESULTS:NBI-magnification endoscopic observation could detect the abnormalities in microvessels and microsurface structures of GI polyps.Overall,we found 5 cases of type A and one case without the examination for the gastric polyps,while there were 4 cases of type B and 2 case of type A for the colorectal polyps.Seventy-nine small-bowel and 115 colorectal polyps over 27 sessions for each were resected endoscopically without significant complications.The only delayed complication included the occurrence of bleeding in a case,and this was successfully managed with hemoclips.Resected polyps contained no malignant components.Based on mutation analysis,all 3 cases in Family I exhibited the +658C>T nonsense mutation in exon 5,which resulted in the production of a truncated protein(Q220X).In Family II,a case had-252C>A and-193C>A in the promoter region.In Family III,a case was found to have the +1062C>G(F342L) mutation in exon 8.CONCLUSION:We found two novel mutations of STK11 in association with PJS.Endoscopic polypectomy of GI polyps in PJS patients appears to be useful to prevent emergency laparotomies and reduce the cancer risk.展开更多
The energy levels and AA bond energy of the double-A hypernucleus nBe are calculated considering two- and three-nucleon forces. The interactions between the constituent particles are contact interactions that reproduc...The energy levels and AA bond energy of the double-A hypernucleus nBe are calculated considering two- and three-nucleon forces. The interactions between the constituent particles are contact interactions that reproduce the low-energy binding energy of the nuclei. Effective action is constructed to involve the three-body forces. In this paper, we compare the binding energy result that is obtained with the experimental and other modern nucleon- nucleon potentials. The results of all the schemes agree very well, showing the high accuracy of our present ability to calculate the many-nucleon bound state with three-body forces. The experimental value of BAA（Be）=20.83 MeV seems to be more compatible with our calculated value of BAA（Be）=-19.31 MeV in comparison with the calculated result of 18.23 MeV by Hiyama et al.展开更多
基金the Natural Science Foundation of Henan Province (0611011900)
文摘A novel double 1：11 series arsenotungstate, [Cu^I（phen）2]5H6[Sm（AsW11O39）2]·6H2O （phen=1, 10-phenanthroline） was synthesized by the hydrothermal method and characterized by elemental analysis, 1R spectra, and single-crystal X-ray diffraction. The title compound was monoclinic, space group P2 1/c, a=3.75710（2） nm, b=1.39776（8） nm, c=-3.33735（18） nm, β=96.967（10）°, V=17.3969（17） nm^3, Z=4. Single crystal X-ray structural analyses revealed that the dimeric polyanion, [SmAs2W22O78]^1-, consisted of one central Sm^3＋ ion and two tetradentate heteropoly ligands [ASW11O39]^7-. The Sm^3＋ ion and two tetradentate defective [AsW11O39]^7- anions were joined together by the sharing of four oxygen atoms from each heteropoly ligand. The bond valence sum （BVS） calculations of the title compound suggested that all four Cu atoms were in the ＋1 oxidation sate.
基金the financial support from the National Natural Science Foundation of China(12171405 and 11661074)the Program for New Century Excellent Talents in Fujian Province University+2 种基金the financial support from the Characteristic&Preponderant Discipline of Key Construction Universities in Zhejiang Province(Zhejiang Gongshang University-Statistics)Collaborative Innovation Center of Statistical Data Engineering Technology&ApplicationDigital+Discipline Construction Project(SZJ2022B004)。
文摘Motivated by recent advances made in the study of dividend control and risk management problems involving the U.S.bankruptcy code,in this paper we follow[44]to revisit the De Finetti dividend control problem under the reorganization process and the regulator's intervention documented in U.S.Chapter 11 bankruptcy.We do this by further accommodating the fixed transaction costs on dividends to imitate the real-world procedure of dividend payments.Incorporating the fixed transaction costs transforms the targeting optimal dividend problem into an impulse control problem rather than a singular control problem,and hence computations and proofs that are distinct from[44]are needed.To account for the financial stress that is due to the more subtle concept of Chapter 11 bankruptcy,the surplus process after dividends is driven by a piece-wise spectrally negative Lévy process with endogenous regime switching.Some explicit expressions of the expected net present values under a double barrier dividend strategy,new to the literature,are established in terms of scale functions.With the help of these expressions,we are able to characterize the optimal strategy among the set of admissible double barrier dividend strategies.When the tail of the Lévy measure is log-convex,this optimal double barrier dividend strategy is then verified as the optimal dividend strategy,solving our optimal impulse control problem.
文摘AIM:To explore mutations in serine/threonine kinase 11(STK11) gene in Peutz-Jeghers syndrome(PJS) with gastrointestinal(GI) hamartomatous polyps.METHODS:Six Japanese PJS patients in 3 families were enrolled in this study.Each of the cases had hamartomatous polyposis in the gastrointestinal tract,including the small intestine,along with mucocutaneous hyperpigmentation.Narrow-band imaging(NBI)-magnification endoscopy was employed to detect microvascular and microsurface irregularities in the GI lesions.NBI magnification findings could be classified into three groups(type A,type B,or type C).Endoscopic polypectomy was performed using double-balloon enteroscopy or colonoscopy.Genomic DNA was extracted from a whole blood sample from each subject.All of the coding exons of STK11 gene,its boundary regions,and the promoter region containing the polymorphic regions were amplified by polymerase chain reaction,and direct sequencing was performed to assess the germline mutations.RESULTS:NBI-magnification endoscopic observation could detect the abnormalities in microvessels and microsurface structures of GI polyps.Overall,we found 5 cases of type A and one case without the examination for the gastric polyps,while there were 4 cases of type B and 2 case of type A for the colorectal polyps.Seventy-nine small-bowel and 115 colorectal polyps over 27 sessions for each were resected endoscopically without significant complications.The only delayed complication included the occurrence of bleeding in a case,and this was successfully managed with hemoclips.Resected polyps contained no malignant components.Based on mutation analysis,all 3 cases in Family I exhibited the +658C>T nonsense mutation in exon 5,which resulted in the production of a truncated protein(Q220X).In Family II,a case had-252C>A and-193C>A in the promoter region.In Family III,a case was found to have the +1062C>G(F342L) mutation in exon 8.CONCLUSION:We found two novel mutations of STK11 in association with PJS.Endoscopic polypectomy of GI polyps in PJS patients appears to be useful to prevent emergency laparotomies and reduce the cancer risk.
文摘The energy levels and AA bond energy of the double-A hypernucleus nBe are calculated considering two- and three-nucleon forces. The interactions between the constituent particles are contact interactions that reproduce the low-energy binding energy of the nuclei. Effective action is constructed to involve the three-body forces. In this paper, we compare the binding energy result that is obtained with the experimental and other modern nucleon- nucleon potentials. The results of all the schemes agree very well, showing the high accuracy of our present ability to calculate the many-nucleon bound state with three-body forces. The experimental value of BAA（Be）=20.83 MeV seems to be more compatible with our calculated value of BAA（Be）=-19.31 MeV in comparison with the calculated result of 18.23 MeV by Hiyama et al.
