High-resolution time-and angle-resolved photoemission measurements were conducted on the topological insulator ZrTe_(5).With strong femtosecond photoexcitation,a possible ultrafast phase transition from a weak to a st...High-resolution time-and angle-resolved photoemission measurements were conducted on the topological insulator ZrTe_(5).With strong femtosecond photoexcitation,a possible ultrafast phase transition from a weak to a strong topological insulating phase was experimentally realized by recovering the energy gap inversion in a time scale that was shorter than 0.15 ps.This photoinduced transient strong topological phase can last longer than 2 ps at the highest excitation fluence studied,and it cannot be attributed to the photoinduced heating of electrons or modification of the conduction band filling.Additionally,the measured unoccupied electronic states are consistent with the first-principles calculation based on experimental crystal lattice constants,which favor a strong topological insulating phase.These findings provide new insights into the longstanding controversy about the strong and weak topological properties in ZrTe_(5),and they suggest that many-body effects including electron–electron interactions must be taken into account to understand the equilibrium weak topological insulating phase in ZrTe_(5).展开更多
High-resolution angle-resolved photoemission measurements were taken on FeSe;S;(x=0,0.04,and 0.08)superconductors.With an ultrahigh energy resolution of 0.4 meV,unusual two hole bands near the Brillouin-zone center,wh...High-resolution angle-resolved photoemission measurements were taken on FeSe;S;(x=0,0.04,and 0.08)superconductors.With an ultrahigh energy resolution of 0.4 meV,unusual two hole bands near the Brillouin-zone center,which was possibly a result of additional symmetry breaking,were identified in all the sulfur-substituted samples.In addition,in both of the hole bands highly anisotropic superconducting gaps with resolution limited nodes were evidenced.We find that the larger superconducting gap on the outer hole band is reduced linearly to the nematic transition temperature while the gap on the inner hole is nearly S-substitution independent.Our observations strongly suggest that the superconducting gap increases with enhanced nematicity although the superconducting transition temperature is not only governed by the pairing strength,demonstrating strong constraints on theories in the FeSe family.展开更多
In order to mine gene loci associated with drought resistance and water use efficiency, and provide guidance for the breeding of drought-resistant wheat varieties, quantitative trait loci (QTLs) for plant height (P...In order to mine gene loci associated with drought resistance and water use efficiency, and provide guidance for the breeding of drought-resistant wheat varieties, quantitative trait loci (QTLs) for plant height (PH) and stem height (SH) of wheat were evaluated using a population of 302 recombinant inbred lines (RILs) derived from a cress between drought-tolerant cultivar Luohan 2 and water-sensitive cultivar Weimai 8 under different water regimes in six environments. Totally 17 additive QTLs for PH and SH were identified and distributed on chromosomes 2B, 3A, 3B, 4A, 5A, 5D, 6B, 7A and 7B, respectively, which explained 3.3% to 26.95% phenotypic variations, with additive effect of 1.919 6 to 5.382 8 cm. Among them, 14 QTLs, 24 times and 5 QTLs, 7 times were detected in three irrigation environments and three drought stress environments, respectively. Both the number of QTLs for PH and the times detected in drought stress environments were significantly less than those in irrigation environments. Of all the 17 QTLs for PH, 12 were detected only in irrigation environment, three QTLs were detected only in drought stress environment, and two QTLs were detected in both environments, suggesting that the expression of the genes is greatly influenced by en- vironmental condition. QPh-WL-7A. 3 detected between maker Xbarc049 and Xgwm273 on chromosome 7A in all the three drought stress environments, can enhance 2.481 5 - 3. 697 2 cm of PH, explain 8.6% - 10.0% additive effect, so it is useful for the genetic improvement of drought tolerance and molecular marker-assisted selection in wheat.展开更多
Variants in the solute carrier family 40 member 1(SLC40A1)gene are the molecular basis of ferroportin disease,which is an autosomal dominant hereditary hemochromatosis.Here,we present a patient with pure red cell apla...Variants in the solute carrier family 40 member 1(SLC40A1)gene are the molecular basis of ferroportin disease,which is an autosomal dominant hereditary hemochromatosis.Here,we present a patient with pure red cell aplasia(PRCA)and large granular lymphocytic leukemia(LGLL)associated with an extremely high levels of serum ferritin and iron overload syndrome.Whole exon sequencing revealed a novel heterozygous variant in SLC40A1(p.T419I),which was found in his daughter as well.A series of functional studies in vitro of the T419I variant in ferroportin were conducted and the results revealed a reduced capacity of iron export from cells without changes in protein localization and its sensitivity to hepcidin.Intracellular iron storage in mutated cells was significantly higher than that of wild-type.These findings suggest that the novel variant p.T419I can cause the classical form of ferroportin disease and an elevated intracellular iron level indicates a potential novel pathogenic mechanism underlying PRCA and LGLL.展开更多
基金support from the National Key R&D Program of China(Grant Nos.2021YFA1400202 and 2021YFA1401800)the National Natural Science Foundation of China(Grant Nos.12141404 and 11974243)+3 种基金the Natural Science Foundation of Shanghai(Grant Nos.22ZR1479700 and 23XD1422200)support from the China Postdoctoral Science Foundation(Grant No.2022M722108)support from the National Key R&D Program of China(Grant Nos.2022YFA1402400 and 2021YFA1400100)the National Natural Science Foundation of China(Grant No.12074248)。
文摘High-resolution time-and angle-resolved photoemission measurements were conducted on the topological insulator ZrTe_(5).With strong femtosecond photoexcitation,a possible ultrafast phase transition from a weak to a strong topological insulating phase was experimentally realized by recovering the energy gap inversion in a time scale that was shorter than 0.15 ps.This photoinduced transient strong topological phase can last longer than 2 ps at the highest excitation fluence studied,and it cannot be attributed to the photoinduced heating of electrons or modification of the conduction band filling.Additionally,the measured unoccupied electronic states are consistent with the first-principles calculation based on experimental crystal lattice constants,which favor a strong topological insulating phase.These findings provide new insights into the longstanding controversy about the strong and weak topological properties in ZrTe_(5),and they suggest that many-body effects including electron–electron interactions must be taken into account to understand the equilibrium weak topological insulating phase in ZrTe_(5).
基金supports from the National Key R&D Program of China(Grant No.2021YFA1401800)the National Natural Science Foundation of China(Grant Nos.11974243 and 12141404)+3 种基金support from a Shanghai talent programsupport from the National Natural Science Foundation of China(Grant No.12074248)Fudan University was supported by the Innovation Program of Shanghai Municipal Education Commission(Grant No.2017–01-07-00-07-E00018)the National Natural Science Foundation of China(Grant No.11874119)。
文摘High-resolution angle-resolved photoemission measurements were taken on FeSe;S;(x=0,0.04,and 0.08)superconductors.With an ultrahigh energy resolution of 0.4 meV,unusual two hole bands near the Brillouin-zone center,which was possibly a result of additional symmetry breaking,were identified in all the sulfur-substituted samples.In addition,in both of the hole bands highly anisotropic superconducting gaps with resolution limited nodes were evidenced.We find that the larger superconducting gap on the outer hole band is reduced linearly to the nematic transition temperature while the gap on the inner hole is nearly S-substitution independent.Our observations strongly suggest that the superconducting gap increases with enhanced nematicity although the superconducting transition temperature is not only governed by the pairing strength,demonstrating strong constraints on theories in the FeSe family.
基金Supported by Scientific and Technological Development Plan of Jining Municipal Government(2013CB030102)Key Technological Project for Independent Innovation of Shandong Province(2014GJJS0201)
文摘In order to mine gene loci associated with drought resistance and water use efficiency, and provide guidance for the breeding of drought-resistant wheat varieties, quantitative trait loci (QTLs) for plant height (PH) and stem height (SH) of wheat were evaluated using a population of 302 recombinant inbred lines (RILs) derived from a cress between drought-tolerant cultivar Luohan 2 and water-sensitive cultivar Weimai 8 under different water regimes in six environments. Totally 17 additive QTLs for PH and SH were identified and distributed on chromosomes 2B, 3A, 3B, 4A, 5A, 5D, 6B, 7A and 7B, respectively, which explained 3.3% to 26.95% phenotypic variations, with additive effect of 1.919 6 to 5.382 8 cm. Among them, 14 QTLs, 24 times and 5 QTLs, 7 times were detected in three irrigation environments and three drought stress environments, respectively. Both the number of QTLs for PH and the times detected in drought stress environments were significantly less than those in irrigation environments. Of all the 17 QTLs for PH, 12 were detected only in irrigation environment, three QTLs were detected only in drought stress environment, and two QTLs were detected in both environments, suggesting that the expression of the genes is greatly influenced by en- vironmental condition. QPh-WL-7A. 3 detected between maker Xbarc049 and Xgwm273 on chromosome 7A in all the three drought stress environments, can enhance 2.481 5 - 3. 697 2 cm of PH, explain 8.6% - 10.0% additive effect, so it is useful for the genetic improvement of drought tolerance and molecular marker-assisted selection in wheat.
基金was supported by grants from the National Natural Science Foundation of China under grant numbers 81770119&81700120。
文摘Variants in the solute carrier family 40 member 1(SLC40A1)gene are the molecular basis of ferroportin disease,which is an autosomal dominant hereditary hemochromatosis.Here,we present a patient with pure red cell aplasia(PRCA)and large granular lymphocytic leukemia(LGLL)associated with an extremely high levels of serum ferritin and iron overload syndrome.Whole exon sequencing revealed a novel heterozygous variant in SLC40A1(p.T419I),which was found in his daughter as well.A series of functional studies in vitro of the T419I variant in ferroportin were conducted and the results revealed a reduced capacity of iron export from cells without changes in protein localization and its sensitivity to hepcidin.Intracellular iron storage in mutated cells was significantly higher than that of wild-type.These findings suggest that the novel variant p.T419I can cause the classical form of ferroportin disease and an elevated intracellular iron level indicates a potential novel pathogenic mechanism underlying PRCA and LGLL.