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Two new cycloartane triterpenoid glycosides, soulieoside V (1) and 15-deacetylbeesioside O (2), together with one known compound, beesioside J (3), were isolated from the ethanolic extract of the rhizomes of Actaea vaginata. Their structures were elucidated by spectroscopic methods and by comparison with data reported in the literature. All the compounds were tested for their cytotoxic activities against human cancer cell lines.

Additional file 1 Supplementary Table 1 Characteristics of included clinical trials in the meta-analysis.

Additional file 2 Supplementary Table 2 Quality assessment of studies included.

One new cycloartane triterpene bisdesmoside, soulieoside U, was isolated from the rhizomes of Actaea vaginata. Its structure was elucidated by extensive analysis of the NMR and MS data. Soulieoside U was evaluated for cytotoxic activities against three human cancer cell lines.

When carrying out special services of rescue and firefighting in buildings, underground works, tunnels and mine, where has no GPS signal, it's important to get location information of special staff, which used by guiding rescue, evacuation and force dispatch. In order to meet the above requirements, this system uses the inertial measurement unit constructed by 3-axis acceleration, 3-axis gyroscope and 3-axis geomagnetic sensor to complete the measurement of pedestrian motion information, calculate the personnel attitude through the cosine matrix, and use the extended Kalman filter the calculation of the speed and position of the personnel is carried out, and the zero speed detection is realized by the gyroscope to reduce the accumulated error of the calculation, thus realizing the key technology of inertial navigation. Using ZigBee and WIFI modules, the development of portable wireless network nodes, to build a wireless self-organizing network. Using embedded microcontrollers and MEMS inertial sensors to build a wearable wireless navigation and positioning system. Using wireless ad hoc network, implement real-time online monitoring of the staff positions and movement trajectory. The wearable wireless navigation and positioning system can accurately obtain the position and movement trajectory of the rescue personnel. Using the wireless ad hoc network, the position and the trajectory information of the rescue personnel can be transmitted to the control center in real time to provide information for the disaster relief command and decision support service.

In this letter, a radio resource allocation scheme based on dynamic user division is proposed to improve the spectral efficiency of OFDMA cellular relay network. For each subchannel, the user selects the relay with the best channel quality and becomes a candidate of the selected relay. The base station (BS) only transmits the user data to the corresponding relay that the user selected on each subchannel, which avoids the user communicating with the relays on bad subchannels. As a result, all user data could be transmitted high efficiently and the overall cellular throughput would be improved. Lastly, a low complexity iterative algorithm is introduced to solve the resource allocation optimization problem, which can improve the allocation efficiency while ensuring load balance among the BS and relays. Simulation results show that the proposed scheme improves throughput and fairness at the same time, therefore, higher spectrum efficiency is obtained.

By introducing the concept of spring energy of permanent dipole and taking the conformations of solvent molecules into account, the formulas of electrostatic solvation energy in equilibrium and nonequilibrium are derived from the explicit solvent scheme, with the spatial distribution of the discrete permanent charges and induced dipoles of the solvent molecules involved. The energy change of solute due to the variation of wave function from the case of vacuum to that in solution is estimated by treating the solvent effect as external field in the iteration cycles of the self-consistent field. The expression for spectral shift is deduced and applied to the processes of light absorption and emission in solution. According to the new formulations, the averaged solvent electrostatic potential/molecular dynamics program is modified and adopted to investigate the equilibrium solvation energy of water molecule and spectral shift of acrolein.

Studies of the ultraviolet spectra and ab initio calculations have been carried out for vitamin E, p -benzoquinone and their complex in the present work. Steady-state absorption spectra have been experimentally measured with a Shimadzu UV-2100S spectrometer at room temperature. Measured values of maximum absorptions of vitamin E and p -benzoquinone in methanol are in excellent agreement with those reported in reference. In theoretical calculations, face-to-face conformations of the electron donor–acceptor (EDA) complex have been selected. The geometries of EDA complexes have been determined by searching for the energy minimum through the variation of the center to center distance between the isolated optimized geometries of the donor and the acceptor. The electronically excited states have been investigated by means of complete active space self-consistent field method associated with 6-31G* basis sets. The state optimizations of S 0 and S 1 for EDA complex reveal that the photoexcitation can directly yield an excited charge transfer (CT) state, and the CT absorption arises from the electron transition between two π-type molecular obitals. Based on the approximations of spherical cavity and point dipole, CT absorption in methanol has been investigated by considering the solvent reorganization energy correction.

Ab initio calculations have been performed to investigate the state transition in photoinduced electron transfer reactions between tetracyanoethylene and biphenyl as well as naphthalene. Face-to-face conformations of electron donor–acceptor (EDA) complexes were selected for this purpose. The geometries of the EDA complexes were determined by using the isolated optimized geometries of the donor and the acceptor to search for the maximum stabilization energy along the center-to-center distance. The correction of interaction energies for basis set superposition error was considered by using counterpoise methods. The ground and excited states of the EDA complexes were optimized with complete-active-space self-consistent-field calculations. The theoretical study of the ground state and excited states of the EDA complex in this work reveals that the S1 and S2 states of the EDA complexes are charge–transfer (CT) excited states, and CT absorption which corresponds to the S0→S1 and S0→S2 transitions arise from π−π* excitation. On the basis of an Onsager model, CT absorption in dichloromethane was investigated by considering the solvent reorganization energy. Detailed discussions on the excited state and on the CT absorptions were made.

Thermodynamics concerns two kinds of states, the equilibrium ones (classical thermodynamics) and the nonequilibrium ones (nonequilibrium thermodynamics). The classical thermodynamics is an extremely important theory for macroscopic properties of systems in equilibrium, but it can not be fully isolated from nonequilibrium states and irreversible processes. Therefore, within the framework of classical thermodynamics, it is significant to explore a new method to solve the questions in the nonequilibrium state. Furthermore, this treatment should be helpful for getting deep comprehension and new applications of classical thermodynamics. For an irreversible process, thermodynamics often takes the assumption of local equilibrium, which divides the whole system into a number of macroscopic subsystems. If all the subsystems stand at equilibrium or quasi-equilibrium states, the thermodynamic functions for a nonequilibrium system can be obtained by some reasonable treatments. However, the concept of local equilibrium lacks the theoretical basis and the expressions of thermodynamic functions are excessively complicated, so it is hard to be used in practice. Leontovich[1] once introduced a constrained equilibrium approach to treat nonequilibrium states within the framework of classical thermodynamics, which essentially maps a nonequilibrium state to a constrained equilibrium one by imposing an external field. In other words, the definition of thermodynamic functions in classical thermodynamics is firstly used in constrained equilibrium state, and the following step is how to extend this definition to the corresponding nonequilibrium state. This theoretical treatment is feasible in principle, but has not been paid much attention to yet. This situation is possibly resulted from the oversimplified descriptions of the Leontovich’s approach in literature and the lack of practical demands. Hence on the basis of detailed analysis of additional external parameters, we derive a more general thermodynamic formula, and apply it to the case of nonequilibrium polarization. The results show that the nonequilibrium solvation energy in the continuous medium can be obtained by imposing an appropriate external electric field, which drives the nonequilibrium state to a constrained equilibrium one meanwhile keeps the charge distribution and polarization of medium fixed.