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Phytochemical investigation of the whole plant of Actaea vaginata led to the isolation of five cycloartane triterpene glycosides, including three new Actaeoside A−C (1 − 3) along with two known analogues, beesiosides E (4) and N (5). Their structures were elucidated by NMR, HRESIMS and chemical analysis. The cytotoxicity of compounds (1 − 5) was assayed against HT-29 and HepG2 cancer cell lines. All the isolates showed moderate degrees of inhibitory activity against the HT-29 with IC 50 values in a range of 18.2–27.8 μM. [Display omitted] • Five cycloartane triterpenoid glycosides were isolated from Actaea vaginata. • Three new and two known compounds were identified by spectroscopic analyses and chemical methods. • Cytotoxicity against HepG2 and HT-29 cancer cell lines were evaluated. [ABSTRACT FROM AUTHOR]

To explore the possible long-term health effects of the defoamer used in seawater desalination by sub-chronic toxicity testing. Blood analysis, internal organ assessment, and histopathological examination were carried out in rats exposed to low, medium, and high (0.5, 1.0, and 2.0 g/kg BW, respectively) doses of defoamer for 90 days through oral administration. The high dose group showed decreased blood alanine aminotransferase and aspartate aminotransferase (P < 0.05). All doses resulted in a significant increase in albumin and decrease in globulin (P < 0.05). The direct bilirubin and indirect bilirubin were decreased in the medium and high dose groups (P < 0.05). All dose groups showed significant induction of alkaline phosphatase (P < 0.05). Pathological examination revealed a case of liver mononuclear cell infiltration in the medium dose group and three cases of liver congestion, steatosis of hepatic cells around the central vein, and punctate necrosis with multiple focal mononuclear cell infiltration in male rats administered the high dose. The No Observed Adverse Effect Level was 0.5 g/kg BW in rats, with albumin and total bilirubin as health effect indices. Long-term defoamer exposure may cause liver injury but has no significant impact on renal function in rats. The effect on blood cells in female rats was more prominent than that in male rats. [ABSTRACT FROM AUTHOR]

In this study, we propose an observer-based adaptive fuzzy controller for a class of nonlinear systems with unknown symmetric nonlinear dead zone input. First, we establish the nonlinear symmetric dead zone model, which is then transformed into a linear symmetric dead zone model for processing. Next, we apply the observer-based adaptive fuzzy control method to the transformed model. The stability of the closed-loop system is proved using the Lyapunov function analysis method. Our simulation results demonstrate that the proposed method achieves the desired performance. [ABSTRACT FROM AUTHOR]

Using Dachengqi Tang (DCQT) as a model, high performance liquid chromatography (HPLC) fingerprints were applied to optimize machine extracting process with the Box–Behnken experimental design. HPLC fingerprints were carried out to investigate the chemical ingredients of DCQT; synthetic weighing method based on analytic hierarchy process (AHP) and criteria importance through intercriteria correlation (CRITIC) was performed to calculate synthetic scores of fingerprints; using the mark ingredients contents and synthetic scores as indicators, the Box–Behnken design was carried out to optimize the process parameters of machine decocting process under high pressure for DCQT. Results of optimal process showed that the herb materials were soaked for 45 min and extracted with 9 folds volume of water in the decocting machine under the temperature of 140 °C till the pressure arrived at 0.25 MPa; then hot decoction was excreted to soak Dahuang and Mangxiao for 5 min. Finally, obtained solutions were mixed, filtrated and packed. It concluded that HPLC fingerprints combined with the Box–Behnken experimental design could be used to optimize extracting process of traditional Chinese medicine (TCM). [ABSTRACT FROM AUTHOR]

Abstract: A novel impulsive control approach based on interval Type-2 T–S fuzzy model has been presented for nonlinear systems in this paper. This approach makes up for the drawback of Type-1 fuzzy impulsive control, which cannot fully handle the uncertainties in describing the complex nonlinear systems by Type-1 fuzzy membership functions and cannot give rigorous fuzzy rules. Further more, this approach uses the “broad band” effect of the Type-2 membership functions to solve the noise of training data and exterior disturbance of the Type-1 fuzzy impulsive control. By using Lyapunov theory and Lipschitz condition, which is combined with integrated approaches such as comparison methods and linear matrix inequalities, the Type-2 fuzzy impulsive controller is designed and the general asymptotical stability analysis of the systems is given. Finally, the simulation of the inverted pendulum model demonstrates the validity and superiority of the proposed method by easily determining the membership functions and choosing minimum number of fuzzy rules and the method can handle random disturbance and data uncertainties very well. [Copyright &y& Elsevier]

Abstract: The concepts of the control and the reconfigurable control, connecting the function of redundancy-complement of ecosystems, are introduced for predator–prey ecosystems with time delay, and the control laws are given when time delay does not change or changes in its respondent, respectively. According to the variations in population density, the fuzzy rule base is established as the criterion of the reconfiguration, and the reconfigurable control laws are obtained. The results of the simulations show the validity of the concepts, and provide the theory instruction for the sustainable development of ecosystems. [Copyright &y& Elsevier]

Abstract: A compact 500.9nm laser was realized using doubly resonant intracavity sum–frequency mixing. An Nd:YAG crystal and an Nd:YVO4 crystal were employed as the gain crystals. In two sub-cavities, 946nm radiation from the Nd:YAG and 1064nm radiation from the Nd:YVO4 were mixed to generate 500.9nm. In the overlapping of the two cavities, sum–frequency mixing was achieved in a type-II critical phase-matched KTP crystal. An output power of 78mW at a wavelength of 500.9nm was generated using a total incident pump power of 4W and the output light exhibited low noise, with the root-mean-square value being 0.3%. [Copyright &y& Elsevier]

The microecology of endophytic fungi in special habitats, such as the interior of different tissues from a medicinal plant, and its effects on the formation of metabolites with different biological activities are of great importance. However, the factors affecting fungal community formation are unclear. This study is the first to utilize "mini-community" remodeling to understand the above phenomena. First, high-throughput sequencing technology was applied to explore the community composition and diversity of endophytic fungi in the above-ground tissues (Ea) and below-ground tissues (Eb) of Ephedra sinica. Second, fungi were obtained through culture-dependent technology and used for "mini-community" remodeling in vitro. Then, the effects of environmental factors, partner fungi, and plant tissue fluid (internal environment) on endophytic fungal community formation were discussed. Results showed that environmental factors played a decisive role in the selection of endophytic fungi, that is, in Ea and Eb, 93.8% and 25.3% of endophytic fungi were halophilic, respectively, and 10.6% and 60.2% fungi were sensitive to high temperature (33 °C), respectively. Meanwhile, pH had little effect on fungal communities. The internal environment of the plant host further promoted the formation of endophytic fungal communities. [ABSTRACT FROM AUTHOR]

In the present paper, a high-order finite volume compact scheme is proposed to solve one dimensional Burgers’ equation. The nonlinear advective terms are computed by the fifth-order finite volume weighted upwind compact scheme, in which the nonlinear weighted essentially non-oscillatory weights are coupled with lower order compact stencils. The diffusive terms are discretized by using the finite volume six-order Padé scheme. The strong stability preserving third-order Runge–Kutta time discretizations is used in this work. Numerical results are compared with the exact and some existing numerical solutions to demonstrate the essentially non-oscillatory and high resolution of the proposed method. The numerical results are shown to be more accurate than some numerical results given in the literature. [ABSTRACT FROM AUTHOR]

In this study, we propose bionic fuzzy sliding mode control based on switching control item fuzzification for a class of uncertain nonlinear systems. We introduce biological adaptation strategies into sliding mode control under uncertain boundary circumstance and disturbances. The main feature of this new method is the design of the switching-type control item in the sliding mode controller based on biological active adaptation strategies. We also analyze the robustness of the bionic fuzzy sliding mode control system and prove the stability of the closed-loop system in the Lyapunov sense. Finally, simulation results obtained for the circle of inverted-pendulum system show that it is effective and feasible. We demonstrate that bionic fuzzy sliding mode control is superior to conventional fuzzy sliding mode control. This method alleviates the chattering phenomenon that affects sliding mode control and ensures that the tracking error stabilizes at zero. [ABSTRACT FROM AUTHOR]

Using the methodology of fuzzy set theory, we discussed the conception in ecology about the hierarchic structure and the dominant species of the community, community crisscross region and the measurement of similarity, the relation between the niche and the community. This showed that the fuzzy set theory be beneficial to study on ecosystem. [Copyright &y& Elsevier]

• Mechanical stress can have a significant effect on marine coating properties. • The factors involved in mechanical effect on coating degradation were discussed. • The water diffusion coefficient is a thermo-activated function of stress level. • The concentration of trapped water can also affect water uptake and diffusion. • Mechanical stress should be considered in corrosion protection design. The degradation behaviour of a marine epoxy coating on Q235 steel under mechanical stress in 3.5 % NaCl solution was investigated by electrochemical impedance spectroscopy (EIS) and adhesion tests. Results revealed that mechanical stress had a significant effect on coating barrier properties, adhesion, delaminated area, water uptake and diffusion, and this effect was not only related to the magnitude and direction of stress, but depended on immersion time. The coating under mechanical stress, regardless of stress direction, deteriorated faster than that under unstressed state. The disparity in changing trends of water uptake and diffusion coefficient with mechanical stress was also discussed. [ABSTRACT FROM AUTHOR]

In this study, the effect of low levels of elastic stress on corrosion behavior of Q235B steel in an aerated 3.5% NaCl solution was investigated through measurements of linear polarization resistance (LPR), potentiodynamic polarization characteristics and electrochemical impedance spectra (EIS). Through theoretical analysis and experimental results, new corrosion models which can distinguish the effect of mechanical stress on the corrosion process of actual marine structures have been respectively proposed on the basis of three representative existing corrosion models. The effect of corrosion models on lifetime assessment was studied by employing a steel plate element subjected to the combined effects of corrosion and mechanical stress. Analytical expressions have been obtained for the structure's lifetime, which is identified with the time when the stress reaches the yield level. An example was presented to demonstrate the combined effects of corrosion and elastic stress on the lifetime assessment of marine structures. [ABSTRACT FROM AUTHOR]

In-situ corrosion characterization of Q235 steel under inhomogeneous elastic stress in 3.5% NaCl solution was investigated by zero resistance ammeter and electrochemical noise techniques combined with a newly developed multi-channel working electrode and reference electrode system. The galvanic corrosion, resulted from the so-called stress cell with the higher stress locations as anodes relative to the low stress locations, could be induced by the applied inhomogeneous elastic stress. The distribution and intensity of anodic and cathodic areas in galvanic corrosion were shown to be a function of corrosion time. The effect of corrosion products on the corrosion behaviour was also discussed. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance Osteoporosis is a chronic epidemic which can leads to enhanced bone fragility and consequent an increase in fracture risk. Traditional Chinese medicine (TCM) formulas have a long history of use in the prevention and treatment of osteoporosis. Antiosteoporotic TCM formulas have conspicuous advantage over single drugs. Systematic data mining of the existing antiosteoporotic TCM formulas database can certainly help the drug discovery processes and help the identification of safe candidates with synergistic formulations. In this review, the authors summarize the clinical use and animal experiments of TCM formulas and their mechanism of action, and discuss the potential antiosteoporotic activity and the active constituents of commonly used herbs in TCM formulas for the therapy of osteoporosis. Materials and methods The literature was searched from Medline, Pubmed, ScienceDirect, Spring Link, Web of Science, CNKI and VIP database from 1989 to 2015, and also collected from Chinese traditional books and Chinese Pharmacopoeia with key words such as osteoporosis, osteoblast, osteoclast, traditional Chinese medicine formulas to identify studies on the antiosteoporotic effects of TCM formulas, herbs and chemical constituents, and also their possible mechanisms. Results Thirty-three TCM formulas were commonly used to treat osteoporosis, and showed significant antiosteoporotic effects in human and animal. The herb medicines and their chemical constituents in TCM formulas were summarized, the pharmacological effects and chemical constituents of commonly used herbs in TCM formulas were described in detail. The action mechanisms of TCM formulas and their chemical constituents were described. Finally, the implication for the discovery of antiosteoporotic leads and combinatory ingredients from TCM formulas were prospectively discussed. Conclusions Clinical practice and animal experiments indicate that TCM formulas provide a definite therapeutic effect on osteoporosis. The active constituents in TCM formulas are diverse in chemical structure, and include flavonoids, lignans, saponins and iridoid glycosides. Antiosteoporotic mechanism of TCM formulas and herbs involves multi regulatory pathways, such as Wnt/β-catenin, BMP/Smad, MAPK pathway and RANKL/OPG system. Phytochemicals from TCM formulas and their compositional herb medicines offer great potential for the development of novel antiosteoporotic drugs. The active ingredients in TCM formulas can be developed in combination as potent drugs, which may exhibit better antiosteoporotic effects compared to the individual compound. [ABSTRACT FROM AUTHOR]

A multiphase mixture model was developed for investigating the characteristics of photo-hydrogen production and substrate degradation under various stacking types. In this work, the entrapped-cell photobioreactor was packed with gel granules containing photosynthetic bacteria (PSB) and the effect of organic loading rate ( OLR ) on the performances of photo-hydrogen production and substrate degradation was studied. It was presented that the numerical simulation results were in good agreement with the reported experimental data, and the relative deviations between the reported experimental data and the numerical simulation results are within the range of −2.8 to +12.4% and −2.9 to +8.4% for the hydrogen production rate ( HPR ) and substrate degradation efficiency ( SDE ), respectively. Moreover, the effects of the OLR and the height of photobioreactor ( H ) under various stacking types were also explored. The results showed that the decrease of the OLR from 7.2 to 4.2 mmol/h and the increase of the H from 0.1 to 0.2 m led to the lower HPR , but were beneficial to enhance the SDE . In addition, more closely stacking type can improve the performances of photo-hydrogen production and substrate degradation owing to the increased mass transfer amount of substrate and products. [ABSTRACT FROM AUTHOR]

Abstract: The candidate recombinant hepatitis E vaccine, HEV 239, protect monkeys against infection by hepatitis E virus (HEV). The safety and immunogenicity of the vaccine for humans was assessed in a randomized controlled phase II clinical trial. The study was conducted in an endemic area of southern China and consisted of a dose scheduling, involving 457 adults and a dose escalation component involving 155 high school students. The results showed that the vaccine is safe and immunogenic for humans and suggest that it could prevent new HEV infection. [Copyright &y& Elsevier]

In this paper, based on the procedure of derivation of the element equation, a simulation study is made in depth and the factors affecting the simulating precision are investigated. First the function of the fluidity from definition, physical significance and coupling solution aspects was analyzed in detail and a new expression, fluidity S, was presented. Then a viscosity model considering the effects of multi-components binder and powder loading was used. Finally, an algorithm for element kij of the stiffness matrix was set up, applying an element analysis method for non-Newtonian and non-isothermal feedstock melts in a thin mold cavity with symmetrical geometry. [Copyright &y& Elsevier]