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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]

• The force experiment of flat roof Trough Concentrator model was carried out in the wind tunnel. • The wind load coefficient of the flat roof Trough Concentrator varies with the vertical and horizontal wind azimuth angle. • The resistance coefficient of flat roof is 67.39% smaller than that of ground. • The most unfavorable conditions appear in the tilt angle of 10°, the horizontal wind azimuth angle of 45° and 315°. • The conical vortex at the edge of the roof makes the wind coefficient between the roof and the ground different. In this paper, the flat roof Trough Condenser (FRTC) model is studied using a wind tunnel high frequency dynamic force measurement experiment. The Trough Condenser's (TC) wind (torque) coefficients were obtained in six azimuths. The regularity and features of the wind coefficient when changing within a horizontal wind azimuth angle of 0°~360° and tilt angle of 0°~90° were analyzed. In addition, the TC on the flat roof and the TC installed on the ground were compared and analyzed. The results showed that the FRTC's resistance coefficient, lift coefficient and fundament tilting torque coefficient are all much greater than the side force coefficient, side torque coefficient and azimuth torque coefficient. When designing the TC's structure, the main consideration is the influence of resistance, fundament tilting torque and lift force. The maximal value of the resistance coefficient is 0.938, the maximal fundament tilting torque coefficient is 0.869, and the maximal value of the lift coefficient is −0.620. In addition, compared with the TC on the ground, the roof's resistance coefficient is 67.39% lower, the lift coefficient is 130.65% lower and the fundament tilting torque coefficient is 68.01% lower. Furthermore, as the wind field on the roof is different from that on the ground, while the height of the condenser is lower, and the parapet shields the condenser to a certain extent, the maximum wind (torque) coefficient is also different when under different working conditions. Finally, the effect of the cone vortex on the roof's edge also impacts these results. [ABSTRACT FROM AUTHOR]

• A new measurement method of wind field characteristics is proposed and its feasibility is verified. • Dimensionless approach is proposed to solve the problem that the traditional method cannot measure the characteristics of the wind field at multiple locations at the same time. • By arranging multiple measuring points, it is used to discuss the fluctuation of wind field characteristics in a certain space area. Wind load is an important factor controlling structural design, and the study of wind field characteristics has been area of interest for many scholars. The bulky nature, high cost and immobility of the experimental equipment are the problems existing in the actual experiment. To study the wind field over a large area, this paper proposes a new type of experimental equipment based on UAV technology. This paper first demonstrates the feasibility of the new equipment by comparing the experimental data with the empirical value. In this paper, the dimensionless method is introduced to effectively solve the problem that traditional instruments cannot obtain wind field data from multiple measuring points at the same time, and the timeliness error caused by different measured times. In order to further explore whether the wind fields of the sea and the beach are significantly different, the profile fitting of the two locations is carried out respectively, and the roughness index is obtained. The analysis results show that when there are only a few trees or buildings with low heights on the coast, the impact on the coastal wind field is small. [ABSTRACT FROM AUTHOR]

In the present study, the hydrodynamic response of the novel semi-submersible floating wind turbine (FOWT) platform "Three Gorges Leading (TGL)" was investigated under the actions of wind, current, and wave load and mooring recovery force. AQWA based on potential flow theory was used to establish the hydrodynamic model of the platform and calculate the hydrodynamic coefficients and frequency domain hydrodynamic response. Premised on the hydrodynamic model, the influence of environmental parameters on the hydrodynamic response of the platform was specifically analyzed, the Kriging-MOGA algorithm was used to establish an approximate prediction model for the frequency domain hydrodynamic response of the platform, and the time domain response of the platform under the predicted hazardous conditions was analyzed using FAST-AQWA (F2A) under the action of aerodynamic-hydrodynamic coupling. Findings were made that the hydrodynamic response of the platform was significantly affected by the aerodynamic load of the blades, and the novel semi-submersible platform was verified to meet the operating requirements of offshore floating wind turbines. • Hydrodynamic response of a novel semi-submersible FOWT platform is studied. • Carry out the sensitivity and correlation analysis of the influence of each environmental parameter. • The Kriging-MOGA prediction model for the frequency domain response of the platform is used for short-term prediction. • F2A is used to calculate the time domain response of the platform under the action of aero-hydrodynamic coupling. [ABSTRACT FROM AUTHOR]

Trough solar collectors exhibit a special structure: a thin mirror surface and a large windward surface. The mechanism of trough solar collectors results in stringent structural deformation requirements. Such requirements include wind load as an important control load whose dynamic effect must be considered in structural design. The natural frequency and mode shapes of a structure are important parameters in the study of dynamics. Therefore, simulation analysis should be performed before analyzing the structural dynamics of trough solar collectors to understand their natural vibration characteristics. In this study, the ANSYS software is first used to establish a finite element model of a trough solar collector for modal analysis. The goal in this step is to obtain the natural frequencies and the mode shapes of the solar collector structure at different pitch angles. Next, field measurements are performed on a prototype of the trough solar collector to obtain the natural dynamic characteristics of the collector. The measured data are then compared with the natural frequencies and mode shapes obtained from the finite element analysis to verify the applicability of the finite element model. A uniform design method is used in the selection of optimal measuring taps, and then this paper verifies the correlation of mode shapes between the finite element and the measurement. Results show that the natural frequencies of the trough solar collector are closely spaced, and the inherent dynamic characteristics measured under various pitch angle coincide with the results of the finite element simulations. Hence, the finite element model of trough solar collectors is applicable. The main contributions of this work include: (1) By means of the modal test in field measurements and the finite element modal analysis, the natural dynamic properties of the trough solar collector can be obtained. (2) Results of modal test could evaluate and improve the accuracy of finite element model, and the results of finite element modal analysis are compared with the field measured modal test results, which verifies the accuracy and the applicability of the finite element model of the channel condenser. (3) Based on the finite element model of the trough solar collector, the information obtained in this work can serve as a reference for subsequent analyses and calculations, such as wind-induced response dynamics analysis. [ABSTRACT FROM AUTHOR]

The distribution contours of mean wind pressure coefficient and fluctuating wind pressure coefficients on mirror surface under typical working conditions were obtained by conducting wind tunnel experiments on trough concentrator model. Meanwhile, the pattern and characteristics of wind pressure distribution on mirror surface were investigated; and the mean wind pressure coefficient distribution on mirror surface was studied. By focusing on fluctuating wind pressure characteristics, the factors influencing fluctuating wind pressure distribution were analyzed, and the power spectra of fluctuating wind pressure on some measuring taps were studied. The non-Gaussian characteristics of the fluctuating wind pressure measured on mirror surface were also assessed on the basis of kurtosis coefficient and skewness coefficient. [ABSTRACT FROM AUTHOR]

Nitrogen containing carbon layer-coated carbon nanotubes (CNx-CNTs) was prepared as the support for platinum nanoparticles (Pt NPs) and their enhanced properties for electrochemical biosensor has been demonstrated in this paper. The CNx-CNTs were obtained from pyrolysis of polydopamine-wrapped CNTs, which were synthesized by a single deposition process based on the oxidative self-polymerization of dopamine on CNTs. It is found that Pt NPs are deposited on the surface of the CNx-CNTs (Pt/CNx-CNTs) with highly dispersion and small particle size (with an average diameter of 1.7 ± 0.3 nm). Compared to the nitrogen-free CNTs supported Pt NP composite (Pt/CNTs), the Pt/CNx-CNTs modified glassy carbon (GC) electrode exhibits superior electrocatalytic performance towards the oxidation of hydrogen peroxide (increase by about 55% of response current). Taking glucose oxidase (GOD) as the model, the proposed amperometric enzyme biosensor based on the Pt/CNx-CNTs shows excellent analytical characteristics to glucose detection, such as excellent sustainability in large range of pH values, high sensitivity (66.51 μA (mmol dm −3 ) −1 cm −2 ), wide linear range (0.01-6.1 mmol dm −3 ) and low detection limit (0.4 μmol dm −3 ). [ABSTRACT FROM AUTHOR]

The wind load is the main control load of the parabolic solar condenser (PSC) due to the special structure thereof. To ensure normal operation of the flat roof parabolic solar condenser (FRPSC), the probability characteristics of the FRPSC's upright post base shear force coefficient were explored in the present study, and the extreme values were analyzed. Multi-order moments were used to conduct Gaussian discrimination of the base shear force coefficient of the FRPSC's upright post. Subsequently, three methods were adopted to calculate the extremum of the base shear force coefficient. By analyzing the FRPSC's upright post base shear force coefficient extreme value, the data obtained by the Sadek-Simiu (SAD) extreme value calculation method were found to be the most accurate. Through the analysis of the base shear force coefficient under 250 working conditions, the change rule of the extreme value was obtained, and then compared with the mean base shear force coefficient. The identification standard of whether the base shear force coefficient of the FRPSC's upright post met the Gaussian distributive was determined, and the Gaussian distribution and non-Gaussian distribution areas were divided. • The Gaussian criterion for the base shear force coefficient of the FRPSC's upright post is given. • The reason why the base shear force is not Gaussian is that the correlation of mirror wind loads is enhanced. • The SAD method is more accurate for the base shear force coefficient of the FRPSC's upright post. • The most unfavorable working condition of base shear force coefficient is 45° horizontal wind azimuth angle and 0° tilt angle. • The extreme value of the base shear force coefficient is the smallest when the horizontal wind azimuth angle is 90°. [ABSTRACT FROM AUTHOR]

Trough Solar Collector system is usually located in the Gobi and other open areas. It has a special structure with the large windward surface made up of thin mirror. Its working regime and working environment make wind load become the most essential load for its structural design. In this paper, the high frequency dynamic force test is carried out in the atmospheric boundary layer wind tunnel of the HD-3 in Hunan University. The testing results are consistent with existing studies, indicating the accuracy of the experiment. The wind load coefficients varying with pitching and yaw angle are obtained. The maximum of wind load coefficients and the most unfavorable conditions are extracted. Then, the wind-induced dynamic response of the Trough Solar Collector is analyzed through finite element model, so that the peak displacement response and wind-induced vibration coefficient of the mirror are obtained. Finally, the pedestal internal force of the Trough Solar Collector column is analyzed. The results show that, when designing the Trough Solar Collector structure, only the influence of drag force, lift force, and base overturning moment need to be considered. The maximum values of drag coefficient and lift coefficient appear in the conditions pitch angle being 10° and 50°, with corresponding yaw angle equaling to 0°. According to the wind-induced dynamic response analysis of the Trough Solar Collector, the maximum peak displacement response appears near the midpoint of the span wise of the collector under various working conditions. The wind-induced vibration coefficient of the collector is between 1.5 and 3.4. The maximum pull-up force of the column pedestal under normal use conditions is 30.7 KN. • The force test is carried out on the Trough Solar Collector model under 130 working conditions. • The change in pitch and yaw angle considerably influences the overall force of the Trough Solar Collector. • The wind-induced dynamic response of the Trough Solar Collector is analyzed by the finite element model. • The maximum value of the peak displacement response appears at the edge near the midpoint of the span wise of the collector. • The pedestal internal force of Trough Solar Collector column under wind load is analyzed under two states. [ABSTRACT FROM AUTHOR]

Hepatic angiomyolipoma (HAML) comprises epithelioid angiomyolipoma (EAML) and classic hepatic angiomyolipoma (CAML). The imaging appearance of HAML varies widely, and EAML is more easily misdiagnosed as hepatocellular carcinoma (HCC) than as CAML. The clinical and contrast-enhanced ultrasound (CEUS) features of CAML, EAML and HCC with negative alpha-fetoprotein protein expression (HCC[AFP-]) were retrospectively reviewed. The hyper-vascular type was more commonly found in CAML and EAML lesions than in HCC lesions. Most lesions were hyper-enhanced in the arterial phase. CAMLs showed prolonged hyper-enhancement or iso-enhancement during the portal and late phases on CEUS, making them easily distinguishable from HCC(AFP-). Some EAML lesions (41.7%) were hypo-echoic, similar to HCC(AFP-). However, the hypo-enhancement of EAML lesions occurred later than that of HCC(AFP-) lesions. Thus, our findings may be useful in distinguishing among these lesions to improve diagnostic accuracy. [ABSTRACT FROM AUTHOR]

• The water quenched slag (WQS) and silica sand tailing (SST) were combined to prepared a novel permeable material (WSPM). • The WSPM with the WQS/SST mass ratio of 2/8 sintered at 1200 °C for 1 h exhibits the best engineering properties. • The prepared WSPM shows stable immobilization for the heavy-metal ions including Zn, Mn, and Cr. This research used the water quenched slag (WQS) and silica sand tailing (SST) to prepare a novel WQS-SST based permeable material (WSPM) by traditional sintering method. Effects of WQS/SST mass ratio and sintering temperature on the structure and properties of the WSPM were discussed. The XRD and SEM-EDS results show that the combination of the WQS and SST can form the glass liquid phase (GLP) which is CaO-Fe 2 O 3 -SiO 2 glass as main composition accompanying with small amount of Al 2 O 3 and one or more trace amounts of Na 2 O/K 2 O/MgO, and promote the synthesis of the WSPM. Both the WQS/SST mass ratio and sintering temperature can affect the formation of the GLP, which further alter the structure and properties of the WSPM. Under the optimum condition (WQS/SST = 2/8, 1200 °C/1h), the prepared WSPM shows the best engineering properties, including the high permeability of 2.03 × 10−2 cm/s and the considerable compressive strength of 26.83 MPa. Meanwhile, the WSPM with the optimum condition shows stable immobilization behavior for the heavy-metal ions of Zn, Mn, and Cr in the ICP test. It indicates that the WSPM in our work is an eco-friendly all-solid-waste based permeable material, which has great application value in the field of permeable bricks for sidewalk construction. [ABSTRACT FROM AUTHOR]

Abstract: Gallbladder cancer (GBC) is a rare, but highly aggressive cancer. The most common type of gallbladder cancer is adenocarcinoma (AC), while squamous cell/adenosquamous carcinoma (SC/ASC) is a rare type of gallbladder cancer. The clinicopathologic and biological characteristics of SC/ASC have not been well documented. In this study, the protein expression of N-cadherin and P-cadherin in 46 SC/ASCs and 80 ACs was measured using immunohistochemistry. We demonstrated that positive N-cadherin and P-cadherin expression were significantly associated with large tumor size, invasion, and lymph node metastasis of both SC/ASC and AC. In contrast, positive N-cadherin and P-cadherin expression were significantly associated with differentiation and TNM stage in only AC. Univariate Kaplan–Meier analysis showed that positive N-cadherin and P-cadherin expression, differentiation, tumor size, TNM stage, invasion, lymph node metastasis, and surgical curability were significantly associated with overall survival in both SC/ASC and AC patients. Multivariate Cox regression analysis showed that positive N-cadherin and P-cadherin expression are independent poor-prognostic factors in both SC/ASC and AC patients. Our study suggested that positive N-cadherin and P-cadherin expression closely correlated with clinicopathological and biological behaviors, and poor-prognosis of gallbladder cancer. [Copyright &y& Elsevier]

Abstract: A sensitive electrochemical method for the detection of hydroxyl radical ( OH) was successfully developed based on magnetic beads (MBs)–DNA–Ag nanoparticles (AgNPs) (MBs–DNA–AgNPs) nanocomposite. MBs were utilized for bioseparation and AgNPs as signal indicator. When OH broke the DNA strands, AgNPs were detached from the surface of the MBs–DNA–AgNPs nanocomposite. Magnetic particles could be easily removed from the solution and the detached AgNPs were collected. Therefore, the anodic stripping voltammetry (ASV) signal of dissolved silver on glassy carbon (GC) electrode depended on the amounts of OH. The results show that the ASV signal linearly increases with the increase of the concentration of OH in the range of 0.05–4μM, and the detection limit is as low as 10nM, which is much lower than the detection limit obtained on the recently developed electrochemical and photoelectrochemical methods. In addition, the developed method has potential application in the screening of antioxidants. [Copyright &y& Elsevier]

Abstract: A high-performance bioanode based on the composite of carbon nanotubes (CNTs)-immobilized mediator and silk film (SF)-immobilized glucose oxidase (GOD) was developed for glucose/O2 biofuel cell (BFC). Ferrocenecarboxaldehyde (Fc) was used as the mediator and covalently immobilized on the ethylenediamine (EDA)-functionalized CNTs (CNTs-EDA). GOD was cross-linked on the SF with glutaraldehyde (GA) as the cross-linking agent. The resulting electrode (CNTs-Fc/SF-GOD/glassy carbon (GC) electrode) exhibited good catalytic activity towards glucose oxidation and excellent stability. For the assembled glucose/O2 BFC with the CNTs-Fc/SF-GOD/GC electrode as the bioanode and a commercial E-TEK Pt/C modified GC electrode as the cathode, the open circuit potential is 0.48V and the maximum power density of 50.70μWcm−2 can be achieved at 0.15V. [Copyright &y& Elsevier]

The ecological risk of heavy metals (HM) resulting from the use of sewage sludge compost (SSC) as an amendment to flower garden soil (FGS) and to abandoned phosphate mine soil (APMS) influenced by acid rain were simulated in lysimeter trials and the potential ecological risk index (PERI) was evaluated with minor modifications. The use of SSC indeed increased the mobility and release of HMs in FGS and APMS under conditions of acid rain. The leaching dynamics of HMs was found to be influenced by Fe/Al oxides and organic matter (OM) in the soil. The application of SSC as a fertilizer to barren APMS dramatically decreased the mobility of Cr, Cu and Pb by 51–56% due to their retention by particulate organic matter, while the leaching of As, Cd and Ni was increased as the result of competition with OM for available Fe/Al oxides (As) and proton-metal exchange reactions that occurred in HM-OM complexes (Cd and Ni). The ecological risk of FGS and APMS resulting from HM migration was actually low (PERI = 0.07–0.12), but the increased potential ecological risk resulting from the use of SSC were estimated to be moderate (a 16.0–33.5% increase in PERI for SSC-amended FGS) or high (a 140% increase in PERI for SSC-amended APMS). Ni, Cd and Cu were identified as the three main HMs responsible for increasing the ecological risk in soil which was mainly composed of fine-grained particles, whereas Cd and As were key ecological risks HMs in soil that was mainly composed of coarse-grained particles. Image 1 • SSC amendment increased HMs release to different extent during acidic percolation. • HM leaching dynamics was influenced by Fe/Al oxides and organic matter. • SSC application to FGS varied with applying rate slightly increased HMs release. • SSC application to APMS stimulated leaching of As, Cd and Ni. • Potential ecological risk increase resulted from SSC amendment was moderate/high. [ABSTRACT FROM AUTHOR]

Micro-RNAs regulate multiple biological behaviors of cancers, making them potential targets of new cancer therapies. MiR-1181 has been demonstrated to perform oncogenic or tumor-suppressing function in a tissue-dependent way, but its role in hepatocellular carcinoma (HCC) was unclear. Here, we showed that miR-1181 was significantly overexpressed in HCC tissues when compared with tumor-adjacent normal ones or normal liver tissues from donated organ, and that inhibition of miR-1181 could repress the growth of HCC cells. Through bioinformatics analysis and luciferase reporter assays, we found that axis inhibition protein 1 (AXIN1) was a direct target of miR-1181, and the expression of AXIN1 showed a negative correlation with that of miR-1181 in HCC. Therefore, these data indicated an oncogenic function of miRNA-1181 in the development of HCC and a potential target for the clinical treatment of HCC. [ABSTRACT FROM AUTHOR]