The discrete-variational method within the framework of density functional theory was used to investigate the process of O2 adsorption occurring on the surface of NiTi alloy. The calculated results showed that O2 exhi...The discrete-variational method within the framework of density functional theory was used to investigate the process of O2 adsorption occurring on the surface of NiTi alloy. The calculated results showed that O2 exhibits the adsorption state of O2- (0.36< 8 <0.70).O2 only interact with one nearest surface Ti atom, and the Ti atom only adsorbs one oxygen atom of the O2 molecule. Other cluster atoms would not be influenced in the adsorption process. The density of state analysis showed that the interaction between Ti and 0 atom is mainly contributed to 2p (0) and 4s (Ti) orbitals.展开更多
The regulation of stomatal movement is one of the most important signaling networks in plants. The H+-ATPase at the plasma membrane of guard cells plays a critical role in the stomata opening, while there are some con...The regulation of stomatal movement is one of the most important signaling networks in plants. The H+-ATPase at the plasma membrane of guard cells plays a critical role in the stomata opening, while there are some conflicting results regarding the effectiveness of the plasma membrane H+-ATPase inhibitor, vanadate, in inhibiting stomata opening. We observed that 2 mmol/L vanadate hardly inhibited light-stimulated stomata opening in epidermal peels of Vicia faba L., but significantly inhibited dark- and ABA-induced stomatal closure. These results cannot be explained with the previous findings that H+-ATPase was inhibited by vanadate. In view of the fact that vanadate is an inhibitor of protein tyrosine phosphatases (PTPases), we investigated whether the stomatal movement regulated by vanadate is through the regulation of PTPase. As expected, phenylarsine oxide (PAO), a specific inhibitor of PTPase, has very similar effects and even more effective than vanadate. Typical PTPase activity was found in guard cells of V. faba; moreover, the phosphatase activity could be inhibited by both vanadate and PAO. These results not only provide a novel explanation for conflicting results about vanadate modulating stomatal movement, but also provide further evidence for the involvement of PTPases in modulating signal transduction of stomatal movement.展开更多
基金This work was financially supported by the National Natural Science Foundation of China,and the number was 50081001.
文摘The discrete-variational method within the framework of density functional theory was used to investigate the process of O2 adsorption occurring on the surface of NiTi alloy. The calculated results showed that O2 exhibits the adsorption state of O2- (0.36< 8 <0.70).O2 only interact with one nearest surface Ti atom, and the Ti atom only adsorbs one oxygen atom of the O2 molecule. Other cluster atoms would not be influenced in the adsorption process. The density of state analysis showed that the interaction between Ti and 0 atom is mainly contributed to 2p (0) and 4s (Ti) orbitals.
基金国家自然科学基金，Doctor's Fund of College and University Education
文摘The regulation of stomatal movement is one of the most important signaling networks in plants. The H+-ATPase at the plasma membrane of guard cells plays a critical role in the stomata opening, while there are some conflicting results regarding the effectiveness of the plasma membrane H+-ATPase inhibitor, vanadate, in inhibiting stomata opening. We observed that 2 mmol/L vanadate hardly inhibited light-stimulated stomata opening in epidermal peels of Vicia faba L., but significantly inhibited dark- and ABA-induced stomatal closure. These results cannot be explained with the previous findings that H+-ATPase was inhibited by vanadate. In view of the fact that vanadate is an inhibitor of protein tyrosine phosphatases (PTPases), we investigated whether the stomatal movement regulated by vanadate is through the regulation of PTPase. As expected, phenylarsine oxide (PAO), a specific inhibitor of PTPase, has very similar effects and even more effective than vanadate. Typical PTPase activity was found in guard cells of V. faba; moreover, the phosphatase activity could be inhibited by both vanadate and PAO. These results not only provide a novel explanation for conflicting results about vanadate modulating stomatal movement, but also provide further evidence for the involvement of PTPases in modulating signal transduction of stomatal movement.
