The universal parameter nonorthogonal tight binding scheme proposed by Menon and Subbaswamy was used to optimize the geometrical structures, binding energies and electron affinities of small germanium clusters Ge ...The universal parameter nonorthogonal tight binding scheme proposed by Menon and Subbaswamy was used to optimize the geometrical structures, binding energies and electron affinities of small germanium clusters Ge n ( n =2—20). A complete agreement with available ab initio results from the lowest energy structures for Ge 2—Ge 6 was obtained and reasonable structures for these clusters were predicted and compared with those of corresponding silicon clusters in the range of n =7—20 . The averaged discrepancy with experiments in binding energies for n =2—7 is about 6% and the calculated electron affinities agree well with the measured values in the range of n =2—8 as well.展开更多
The electronic structures of small aluminum clusters,Al_(n)(n=5-24),are investigated by a localized-orbital theory based on the tight-binding approximation.Magic-numbered clusters each exhibit a HOMO-LUMO gap maximum,...The electronic structures of small aluminum clusters,Al_(n)(n=5-24),are investigated by a localized-orbital theory based on the tight-binding approximation.Magic-numbered clusters each exhibit a HOMO-LUMO gap maximum,and simultaneously an s-p gap minimum,but not necessarily an ionization potential maximum,where HOMO-LUMO gap denotes the energy gap between the highest occupied orbital and the lowest unoccupied orbital of the cluster.Also revealed is an irregular odd-even alternation in HOMO-LUMO gaps for Al_(n)(n=7-24).Cluster geometry either contributes to or dominates these findings.展开更多
The interplay between experiments and theory has been playing an important role from the very beginning of fullerene and carbon nanotube science. In this talk, we will present our most recent studies on computational ...The interplay between experiments and theory has been playing an important role from the very beginning of fullerene and carbon nanotube science. In this talk, we will present our most recent studies on computational fullerene and single-walled carbon nanotube (SWCNT) chemistry.展开更多
Background Rheumatoid arthritis （RA） is an autoimmune disease characterized by chronic inflammation at the synovial membrane. Although great progress has been made recently in exploring the etiology and pathogenesis...Background Rheumatoid arthritis （RA） is an autoimmune disease characterized by chronic inflammation at the synovial membrane. Although great progress has been made recently in exploring the etiology and pathogenesis of RA, its molecular pathological mechanism remains to be further defined and it is still a great challenge in determining the diagnosis and in choosing the appropriate therapy in early patients. This study was performed to screen candidate RA-associated serum proteins by comparative proteomics to provide research clues to early diagnosis and treatment of RA. Methods Sera isolated from 6 RA patients and 6 healthy volunteers were pooled respectively and high-abundance proteins were depleted by Plasma 7 Multiple Affinity Removal System. The protein expression profiles between the two groups were then compared by two-dimensional gel electrophoresis （2-DE） and the proteins over/under-expressed by more than 3-fold were identified by mass spectrometry analysis. To validate the differential expression levels of the identified proteins between the two groups, ELISA was performed in two of the identified proteins in individual sera from 32 RA patients and 32 volunteers. Results Eight proteins which over/under-expressed in sera of RA patients were identified. Among them, chain A of transthyretin （TTR） was under-expressed, while serum amyloid A protein, apolipoprotein A （ApoA）-IV, ApoA-IV precursor, haptoglobin 2, ceruloplasmin （Cp）, immunoglobulin superfamily 22 and HT016 were over-expressed. ELISA test confirmed that Cp expressed remarkably higher while TTR obviously lower in RA group compared with volunteer group. Conclusion There were 8 identified proteins differentially expressed between RA group and volunteer group, which might be candidate RA-associated proteins and might be promising diagnostic indicators or therapeutic targets for RA.展开更多
文摘The universal parameter nonorthogonal tight binding scheme proposed by Menon and Subbaswamy was used to optimize the geometrical structures, binding energies and electron affinities of small germanium clusters Ge n ( n =2—20). A complete agreement with available ab initio results from the lowest energy structures for Ge 2—Ge 6 was obtained and reasonable structures for these clusters were predicted and compared with those of corresponding silicon clusters in the range of n =7—20 . The averaged discrepancy with experiments in binding energies for n =2—7 is about 6% and the calculated electron affinities agree well with the measured values in the range of n =2—8 as well.
基金Supported by the National Natural Science Foundation of China under Grants Nos.19574059 and 19634030.
文摘The electronic structures of small aluminum clusters,Al_(n)(n=5-24),are investigated by a localized-orbital theory based on the tight-binding approximation.Magic-numbered clusters each exhibit a HOMO-LUMO gap maximum,and simultaneously an s-p gap minimum,but not necessarily an ionization potential maximum,where HOMO-LUMO gap denotes the energy gap between the highest occupied orbital and the lowest unoccupied orbital of the cluster.Also revealed is an irregular odd-even alternation in HOMO-LUMO gaps for Al_(n)(n=7-24).Cluster geometry either contributes to or dominates these findings.
文摘The interplay between experiments and theory has been playing an important role from the very beginning of fullerene and carbon nanotube science. In this talk, we will present our most recent studies on computational fullerene and single-walled carbon nanotube (SWCNT) chemistry.
基金This study was partly supported by grants from National Natural Science Foundation of China （No. 30325019 and 30471611）, Natural Science Foundation of Guangdong Province （No. 05001703） and Science and Technology Project of Guangdong Province （No. 2008B030301039）.Acknowledgments： We thank the patients and healthy volunteers who participated in this study, and also thank Shanghai Applied Protein Technology Co. Ltd for performing the spectrometry analysis and providing technical support for the 2-DE experiment.
文摘Background Rheumatoid arthritis （RA） is an autoimmune disease characterized by chronic inflammation at the synovial membrane. Although great progress has been made recently in exploring the etiology and pathogenesis of RA, its molecular pathological mechanism remains to be further defined and it is still a great challenge in determining the diagnosis and in choosing the appropriate therapy in early patients. This study was performed to screen candidate RA-associated serum proteins by comparative proteomics to provide research clues to early diagnosis and treatment of RA. Methods Sera isolated from 6 RA patients and 6 healthy volunteers were pooled respectively and high-abundance proteins were depleted by Plasma 7 Multiple Affinity Removal System. The protein expression profiles between the two groups were then compared by two-dimensional gel electrophoresis （2-DE） and the proteins over/under-expressed by more than 3-fold were identified by mass spectrometry analysis. To validate the differential expression levels of the identified proteins between the two groups, ELISA was performed in two of the identified proteins in individual sera from 32 RA patients and 32 volunteers. Results Eight proteins which over/under-expressed in sera of RA patients were identified. Among them, chain A of transthyretin （TTR） was under-expressed, while serum amyloid A protein, apolipoprotein A （ApoA）-IV, ApoA-IV precursor, haptoglobin 2, ceruloplasmin （Cp）, immunoglobulin superfamily 22 and HT016 were over-expressed. ELISA test confirmed that Cp expressed remarkably higher while TTR obviously lower in RA group compared with volunteer group. Conclusion There were 8 identified proteins differentially expressed between RA group and volunteer group, which might be candidate RA-associated proteins and might be promising diagnostic indicators or therapeutic targets for RA.
