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Guided by cell-based anti-anaphylactic assay, eighteen cage-like monoterpenoid glycosides ( 1 - 18 ) were obtained from the bioactive fraction of P. lactiflora extract. Among these, compounds 1 , 5 , 6 , 11 , 12 , 15 , and 17 can significantly reduce the release rate of β-HEX and HIS without or with less cytotoxicity. Additionally, the most potent inhibitor benzoylpaeoniflorin ( 5 ) was selected as the prioritized compound for the study of action of mechanism, indicating that its anti-anaphylactic activity was medicated by dual-inhibiting HDC and MAPK signal pathway. Moreover, the molecular docking simulation explained that benzoylpaeoniflorin ( 5 ) could block the conversion of L-histidine to HIS by occupying the HDC active site. Finally, in vivo on PCA using BALB/c mice, benzoylpaeoniflorin ( 5 ) can suppress the IgE-mediated PCA reaction in antigen-challenged mice. These findings indicate that cage-like monoterpenoid glycosides, especially benzoylpaeoniflorin ( 5 ), mainly contributed to the anti-anaphylactic activity of P. lactiflora by dual-inhibiting HDC and MAPK signal pathway. Therefore, benzoylpaeoniflorin ( 5 ) may be considered as a novel drug candidate for the treatment of anaphylactic diseases.

A new scheme to create a closed toroidal magnetic waveguide for deBroglie wave on a single layer atom chip is proposed and there is no zero magnetic field along the guide center. The guide is a two-dimensional magnetic trap for trapping weak-field seeking states of atoms with a magnetic dipole moment. The designed wire structure on the atom chip consists of three concentric and isometric ring wires, and six vertical current leads of the three ring wires. By using the through silicon via technology, the current leads can be made perpendicular to the atom chip surface instead of being generally arranged side by side on the chip surface. Compared with the general wiring way, the vertical lead way has two advantages. One is that each ring wire gap caused by the current leads is substantially smaller than the distance between the ring wires, which permits the generation of a closed toroidal magnetic guide near the atom chip surface when dc currents are supplied to the three ring wires. The other is that the distance between two leads of each ring wire is considerably reduced, resulting in the fact that the magnetic perturbation of the leads to the whole toroidal magnetic guide is negligible. We numerically calculate the magnetic field distribution generated by our wire layout when dc currents are applied, and it is shown that a closed and tight toroidal magnetic guide is formed near the atom chip surface. However, there are zero magnetic fields existing along the center of the toroidal guide, which leads to Majorana spin flips from trapped magnetic substate to an un-trapped magnetic sub-state. According to the time-orbiting-potential principle, we propose an ac current modulation method, which is simple and stable, to reduce the atom losses and suppress the atomic decoherence in the toroidal magnetic guide. We deduce the ac current expressions for the case of three isometric infinite straight wires and apply the ac modulation current expressions directly to our three ring wire structure. The numerical calculation results show that the closed toroidal guide does no longer have zero magnetic fields near the magnetic field minimum, and that the magnetic field fluctuation of the guide is smaller. Based on the vertical leads and ac current modulation, the closed toroidal wave guide with no zero magnetic field along the guide center can be generated near the atom chip surface. This scheme has important scientific significance and engineering value for developing the cold atomic chip gyroscope.

The classical four-state component model haven't accord to practical situation because the equipment repairing technique based on condition of component developed quickly, and this paper put forwarded an advanced four state component model. That model redefined abnormal state and maintainable state, combined repair state based on condition of component and schedule repair state to repair state and then confirmed the conversion relationship and the parameter to each state. This paper put forwarded combining components and dividing subzone method to simplify the main electrical scheme to be a simple directional network, applied advanced four state component model in that network to calculate the subzone's reliability parameter. Applied the least path searching method to search the least path matrix for the network and predigested the method by matrix multiplication, enumerated each fault state of that network by analytical method, worked out the reliability index of that network by VC++. And the reliability index of network is the reliability index of main electrical scheme in ChuXiong plusmn800 kV rectifier station. At last this paper analyzed the result of main electrical scheme's reliability and it proved the method's validity which used in this paper.

A novel and simple method to realize polarization gradient cooling (PGC) is reported. The stabilizing, shifting and rapid tuning of the frequency of the external cavity diode laser is realized by using the Zeeman-effect-assisted Doppler-free saturated absorption technique. Based on this convenient technique, 87Rb cold atoms are captured from room-temperature background vapor in the magneto-optical trap (MOT). Meanwhile, the steady-state number, the density and the lifetime of atoms in the MOT are measured. Subsequently, a frequency-fast-varying circuit is designed to realize PGC, which is demonstrated effectively and reliably in experiments. The temperature of the cold atom cloud is measured by two different methods, which coincide with each other.

A simple method to realize both stabilization and shift of the frequency in an external cavity diode laser (ECDL) is reported. Due to the Zeeman effect, the saturated absorption spectrum of Rb atoms in a magnetic field is shifted. This shift can be used to detune the frequency of the ECDL, which is locked to the saturated absorption spectrum. The frequency shift amount can be controlled by changing the magnetic field for a specific polarization state of the laser beam. The advantages of this tunable frequency lock include low laser power requirement, without additional power loss, cheapness, and so on.