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Selaginella tamariscina (ST), a well-known traditional medicinal plant, has been used to treat various cancers, including pancreatic cancer. However, the underlying mechanism by which Selaginellin B, a natural pigment isolated and purified from ST, protects against pancreatic cells has yet to be fully elucidated. In the present study, the biological functions of Selaginellin B were investigated using apoptosis, migration and colony formation assays in ASPC-1 and PANC-1 cells. In addition, apoptosis-associated proteins were detected by Western blotting. Our results demonstrated that Selaginellin B induced apoptosis, as evidenced by the increased cleaved caspase-3 level and Bax/Bcl-2 ratio. Moreover, Selaginellin B led to a marked up-regulation of the ratio of LC3-II/LC3-I in ASPC-1 and PANC-1 cells, respectively. Furthermore, reverse pharmacophore screening, molecular docking and molecular dynamics simulation studies revealed that Janus kinase 2 (JAK2) may be a potential target for Selaginellin B. In summary, the results of the present research have demonstrated that Selaginellin B is an effective anticancer agent against PANC-1 and ASPC-1 cells, and the compound holds great promise for the treatment of pancreatic cancer.

The Molten Salt Fast Reactor is a reactor concept developed by the European Union based on a liquid fuel salt circulating through the reactor core. A peculiar emergency system, which takes advantage of the liquid fuel state, is represented by a tank located underneath the core, where the fuel can be passively drained and cooled; its geometry ensures that the fuel remains in subcritical conditions. In the framework of the SAMOFAR project, a design for the Emergency Draining Tank has been proposed: the tank shall be equipped with vertical cooling elements, arranged in a hexagonal grid; the liquid fuel salt, which heats up due to decay heat, will fill the gaps between the elements. In this work, analytical methods (Green’s functions and orthogonal decomposition) are employed to study the transient heat transfer associated with the proposed design and to perform a preliminary dimensioning of the system, such that overheating is avoided in any moment of the transient and the fuel salt is kept in a liquid state and in safe conditions for a long time. The models are constituted by multilayer monodimensional slabs and cylinders, with a pure heat conduction model. The assessment of the available grace time and preliminary considerations about fuel salt freezing and its influence on the system effectiveness are also included.

In order to predict the coupled motion and external wave load for the design of deepwater floating structure system, based on the three-dimensional time-domain potential flow theory, this paper present the indirect time-domain dynamic coupling method and the body nonlinear dynamic coupling method. The perturbation expansion theory is adopted to evaluate hydrodynamic on the fixed mean wetted body surface for the former method. The transient free surface Green function has been extended and applied to calculate the nonlinear hydrodynamic on the instantaneous wetted exact body surface for the latter method. The finite element model is employed to solve dynamic response of mooring line. Then asynchronous coupled method is adopted to achieve the coupled dynamic analysis of platform and mooring lines. The time-domain motion responses and spectrum analysis of Spar platform are verified and compared with the traditional indirect time-domain coupling dynamic method when the mooring system is completed. Also the time-domain motion responses and statistical characteristic of Spar platform are investigated with one mooring line broken in extreme sea condition. Some conclusions are obtained, that is, dynamic coupling effects are significant and transient position hydrodynamic calculation of platform has a great influence on the low frequency motion. The results also show that the influence on the global performance of mooring system is different when the broken line is in different place. A remarkable influence occurs when the broken mooring line is in the head-wave direction.

The MPP of Photovoltaic power system undergoes migration or volatility under the influence of the external environments, especially light intensity changes. MPPT control is a very important method to increase the efficiency of the photovoltaic power generation system. But the existing variable step length incremental conductance method would produce misjudgment or even tracking failure when outside light intensity mutations. A variable step length incremental conductance MPPT control method based on power prediction has been proposed. This involves modeling, simulation and comparison of the different methods in the Matlab/Simulink environment. The proposed method can not only avoid misjudgments but can also track the MPP efficiently, improving the control accuracy compared with the variable step length incremental conductance method.

In distribution network, the single-phase ground fault accounted for 80% of all distribution networks’ fault. How accurately, rapidly to diagnosis faults lines are practical issues that electrical engineers often meet with. The current of small-current system is so little that could be easily affected by the environment changes and the influence parameters of itself. The single method of line selection cannot conform to the requirements. In this paper, the fifth harmonic of zero-sequence current, line's power and energy of the zero-sequence current are used as the fault feature. Based on the three characteristics and BP neural network, the multi-information line selection was operation. The results of simulation indicate that the multi-information line selection method is much better than the single line selection methods.

The adsorption kinetics of methylene blue from aqueous solutions on purified palygorskite was investigated. The kinetics data related to the adsorption of methylene blue from aqueous solutions are in good agreement with the pseudo-second order equation in ranges of initial concentration of 120-210 mg/L, oscillation speed of 100-200 r/min and temperature of 298-328K. The experimental results show that methylene blue is only adsorbed onto the external surface of purified palygorskite, and the apparent adsorption activation energy is 13.92 kJ/mol. The relatively low apparent adsorption activation energy suggests that the adsorption of methylene blue involves in not only a chemical, but also a physical adsorption process, and it is controlled by the combination of chemical adsorption and liquid-film diffusion.

In order to investigate the chemical constituents of the roots of Glycyrrhiza uralensis Fisch, the constituents were isolated by using preparative HPLC. The structures of the isolated compounds were identified by spectral evidence. A new oleanane-type triterpenoid saponin (S3) and 11 known compounds were obtained. The new licorice saponin (S3) was identified as 22β-acetoxyl-glycyrrhaldehyde based on MS, UV, IR and NMR spectroscopic data.

The quantitative structure--retention relationship is one of the most actively studied topics in the field of chromatography. In this paper, retention parameters of components were used to discriminate the xanthones in a methanol extract of Swertia franchetiana The extract was analysed by HPLC under two different multistage linear gradient conditions and the retention parameters calculated from these retention data. It was found that the retention parameters of xanthones are in a specific region in the plot of log k(w) vs. S and the xanthones in the extract could be distinguished from other components by this feature. Furthermore, xanthone aglycones and xanthone glucosides could also be discriminated by retention parameters.