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Purpose Koningic acid (KA), a sesquiterpene lactone, has been identified as an antimicrobial agent. Recent studies have revealed KA’s antitumor activities in colorectal cancer, leukemia, and lung cancer. However, its antitumor effect in thyroid cancer remains largely unknown. Methods The effects of KA on proliferation, colony formation, apoptosis in thyroid cancer cells were assessed by MTT assay and flow cytometry. After KA treatment, the glycolysis ability of thyroid cancer cells was detected by ECAR, and the glycolytic products and relative ATP levels were measured by ELISA. The underlying mechanisms of antineoplastic activity of KA in thyroid cancer were detected by Western blot. Finally, the antineoplastic activity in vivo was observed in Xenograft mouse models. Results KA inhibited the proliferation, colony formation, and increased cell apoptosis in thyroid cancer cell lines in a dose and time-dependent manner. We verified that the glycolysis ability, ATP production, and lactic acid level in thyroid cancer cells had experienced an extensive decrease after KA treatment. In addition, lactic acid, the metabolite of glycolysis, could weaken the effect of KA on its colony formation ability in C643 thyroid cancer cell line. Our data also showed that KA kills thyroid cancer cells by inhibiting the MAPK/ERK pathway and decreasing Bcl-2 level. By contrast with the control group, the growth of xenograft tumor was dramatically inhibited by KA without obvious drug side effects. Conclusion Our data demonstrate that KA kills thyroid cancer cell lines by inhibiting their glycolysis ability, the MAPK/ERK pathway and the Bcl-2 level and suggest that KA has potential clinical value in thyroid cancer therapy.

Design and fabrication of high-efficiency electrocatalysts are important to generate hydrogen via urea electrocatalysis with the minimum required energy. In this study, in situ growth of a branch-like Mo-doped Ni3S2 nanoforest on Ni foam was achieved through a facile one-pot hydrothermal process. The as-obtained catalyst exhibited excellent activity and robust durability because of its unique hierarchical nanostructures and doping-optimized electronic structural configuration, and required merely 1.33 V (vs. RHE) and 90 mV (overpotential) to attain a current density of 10 mA cm−2 for the urea oxidation reaction (UOR) and hydrogen evolution reaction (HER), without any noticeable loss in activity even after 120 h of operation. On the basis of the experimental results and theoretical calculations, it was confirmed that the incorporation of Mo in Ni3S2 altered the morphology and electronic structure of the catalyst; hence, more active sites were exposed and the Gibbs adsorption energy of the intermediates in the UOR was optimized. Notably, the overall urea electrolysis cell could afford a low voltage of 1.45 V (vs. RHE) to attain a current density of 10 mA cm−2 and showed excellent durability over 120 h. The findings from this study provide new insights into efficient electrocatalysts for urea electrolyzers, which hold great potential in electrochemical energy conversion and sewage treatment applications.

In this study, an integrated fault-tolerant control (IFTC) approach with a two-layer structure is proposed for longitudinal manoeuvre of the hypersonic vehicle with elevator deflection faults. On the top, longitudinal manoeuvre trajectory optimisation problem being subjected to state and input constraints is formulated. The minimum oscillation is taken as the objective function, and the direct collocation method is introduced to calculate the optimal manoeuvre reference trajectory online. On the bottom, diverse elevator deflection faults of the hypersonic vehicle are considered. The faulty longitudinal model is reformulated by input–output feedback linearisation, and the faults are equivalently lumped into additional uncertainties. For the lumped uncertainties and high-order derivatives of velocity and altitude of manoeuvre feasible trajectory, an extended state observer is used for online estimation. The fault-tolerant control based on continuous model predictive control is designed, where predictive models are derived by Taylor expansion approximation. To guarantee that the control inputs do not violate constraints, the analytical control law is improved by the optimal-aim distance criterion. The stability of the closed-loop control system and boundedness of observation errors are proved. The simulations verify the effectiveness of the proposed IFTC approach.

Urea electrolysis is a potential energy-efficient hydrogen (H2) production method that can simultaneously purify urea-rich wastewater. However, the lack of inexpensive and effective electrocatalyst...

Purpose: Koningic acid (KA), a sesquiterpene lactone, has been identified as an antimicrobial agent. Recent studies have revealed KA’s antitumor activities in colorectal cancer, leukemia, and lung cancer. However, its antitumor effect in thyroid cancer remains largely unknown. The aim of this study is to test the therapeutic potential of KA in thyroid cancer and explore the mechanisms underlying antitumor effects.Methods: We examined the effects of KA on proliferation, colony formation, apoptosis, ATP deprivation, and xenograft tumor growth in thyroid cancer cells.Results: KA inhibited thyroid cancer cell proliferation, colony formation, and induced cell apoptosis in a dose and time-dependent manner. Our data also showed that KA caused a rapid, extensive decrease of ATP levels in thyroid cancer cells. Growth of xenograft tumor derived from the thyroid cancer cell line C643 in nude mice was significantly inhibited by KA. Importantly, KA treatment did not cause significant liver and kidney damage in mice compared with the control group.Conclusion: KA may be used as an effective and safe agent for thyroid cancer treatment.

The preload load on concrete during heating is considered to cause a ‘densification’ of cement mortar which led to the increased compressive strength. In order to assess the influence of coupled load and heating effects on porosity characteristics of concrete, the porosity of mortar after mechanical and thermal loading was measured by X-ray computed tomography (X-ray CT). The preload at pre-stress ratios of 0, 0.2, 0.4, and 0.6 (ratio of stress applied to the specimen to its compressive strength at room temperature) were applied on mortar specimens during heating. The residual compressive strengths of the heated and stressed mortar specimens were tested after cooling to room temperature. Combined analyses of the residual compressive strength test results and porosity test results, it shows that the porosity of the specimens under the coupled stressing and heating conditions were slightly lower than that under the unstressed conditions, however, the conclusion that the increase of compressive strength of stressed mortar was caused by the ‘densification’ of cement paste was insufficient. The preload reduced the cracks in the mortar, especially the crack induced due to the thermal mismatch in aggregates and hardened cement paste (HCP), and this may account for the increased compressive strength of stressed mortar.

This paper presents studies that focus on fire and explosion-induced damage of tunnel structures by employing the Discrete Element Method (DEM). By assuming a two-dimensional aggregate distribution and reconstructing the digital representation of the experimental concrete blocks, a numerical model of the tunnel lining concrete was established in the PFC2D program. The temperature distribution and the shock wave pressure at the surface of the tunnel lining were obtained by using Fluent and LS-Dyna separately; the final damage simulation of concrete section under different conditions was carried out in PFC2D. The results showed that PFC2D cooperatively provided more accurate and effective modeling and visualization of impact damage of concrete blocks. The visualizations of damage indicated the degree of damage more clearly and more intuitively. These findings also provide a potential method for further study of the damage assessment for entire tunnel lining structures. Published version

Concrete preloaded during heating always shows higher compressive strength than that unloaded, and the reason was confused. As one of the main components of concrete, cement mortar has an important impact on the performance of concrete at high temperatures. However, few studies have conducted on the stressed mechanical properties strength of mortar at high temperature. In this paper, a series of mechanical tests were conducted to investigate the mechanical properties of cement mortar specimens under axial loading conditions. Seven temperatures (20 °C, 100 °C, 200 °C, 300 °C, 400 °C, 500 °C, 600 °C) and three pre stress ratios (0.2, 0.4, 0.6) were set during the in-door laboratory tests. Test results showed that temperature and pre-stress have significant influences on the compressive strength and the failed mode of cement mortar specimens at high temperature. The compressive strength of mortar under stressed condition was even higher than that at room temperature which might be a reason for the improvement of stressed compressive strength.

Reinforced concrete (RC) beams will be affected by various external environmental in the service process, of which low-temperature is a representative factor. This paper presents a study on using the low-temperature damage test on damage and fracture of RC beams, and an acoustic emission (AE) system is used to monitor the whole process of testing. In the low-temperature damage test, AE hits are used to characterize the damage of each cooling step, and the low-temperature damage of the beam is divided into three processes: initial damage, extended damage and attenuated damage. A damage parameter (DTEM ) based on the accumulated energy of AE is used to analyze the whole process of low-temperature damage of the beam, and the percentage of low-temperature damage in each cooling step is obtained. The environment chamber is used to simulate the extreme low-temperature environment, and the damage of RC beam after the sudden temperature drop (process I) and the end of cooling (process II) is obtained. These two processes have important reference value for the damage degree analysis and damage warning of RC beams in the actual extreme low-temperature environment.

In this paper, a reusable launch vehicle (RLV) attitude control problem with actuator faults is addressed via the robust adaptive nonlinear fault-tolerant control (FTC) with norm estimation. Firstly, the accurate tracking task of attitude angles in the presence of parameter uncertainties and external disturbances is considered. A fault-free controller is proposed using dynamic surface control (DSC) combined with fuzzy adaptive approach. Furthermore, the minimal learning parameter strategy via norm estimation technique is introduced to reduce the multi-parameter adaptive computation burden of fuzzy approximation of the lump uncertainties. Secondly, a compensation controller is designed to handle the partial loss fault of actuator effectiveness. The unknown maximum eigenvalue of actuator efficiency loss factors is estimated online. Moreover, stability analysis guarantees that all signals of the closed-loop control system are semi-global uniformly ultimately bounded. Finally, illustrative simulations show the effectiveness of the proposed method.

In this paper, an acceleration sensing node for pavement vibration was developed to monitor traffic information, including vehicle speed, vehicle types, and traffic flow, where a hardware design with low energy consumption and node encapsulation could be accomplished. The service performance of the sensing node was evaluated, by methods including waterproof test, compression test, sensing performance analysis, and comparison test. The results demonstrate that the sensing node is low in energy consumption, high in strength, IPX8 waterproof, and high in sensitivity and resolution. These characteristics can be applied to practical road environments. Two sensing nodes were spaced apart in the direction of travelling. In the experiment, three types of vehicles passed by the monitoring points at several different speeds and values of d (the distance between the sensor and the nearest tire center line). Based on cross-correlation with kernel pre-smoothing, a calculation method was applied to process the raw data. New algorithms for traffic flow, speed, and axle length were proposed. Finally, the effects of vehicle speed, vehicle weight, and d value on acceleration amplitude were statistically evaluated. It was found that the acceleration sensing node can be used for traffic flow, vehicle speed, and other types of monitoring.

Phosphogypsum-slag-clink (PSC) cement were prepared by original phosphogypsum(PG), which was grinded after dried at 60 °C combined with different contents of phosphogypsum (15%, 20%, 30%), and a small amount of different C3A, C4AF contents of finely ground cement clinker, and ground granulated blast furnace slag (GGBFS). Physical mechanical and sugaring properties were studied. The results show that compressive strength of PSC cement with 20% phosphogypsum at 3 d ages would be higher than 17 MPa and even 50 MPa at 28 days. Compressive strength at longer curing stage and sugaring properties of PSC with lower content of C3A higher C4AF clinker were improved. pH value of PSC cement system at early stage was relatively low, and pH gradually increased with the addition of clinker. pH increased firstly and then decreased with the hydration stage. SEM analyses showed that the amount of ettringite, which was influenced by pH and content of Al, must be controlled in PSC cement system, which may cause damage to microstructure or even expansive cracks if large amount of ettringite formed in hardened paste.

We have previously reported on electrically pumped random lasing (RL) with onset voltages at least 3.3 V from ZnO-based light-emitting devices with metal–insulator–semiconductor (MIS) structures in the form of Au/SiO2/ZnO. Here, by inserting an ∼5 nm thick MoO3 layer between SiO2 and ZnO films in the aforementioned MIS structured device, the RL onset voltage is decreased to only ∼2.6 V and, moreover, the output optical power is multiplied several times. Such improved RL performance is ascribed to the enhanced injection of holes into ZnO via the MoO3 interlayer that features a low-lying conductive band and therefore a large work function.

Coal gangue and clay shale usually contain more than 70 % SiO2 and Al2O3, which have potential pozzolanic activity when calcined at suitable temperature. In this study, the feasibility of utilizing calcined coal gangue and clay shale in the production of multiple cementitious materials was assessed under the condition of no cement clinker. The minerals and chemical composition of coal gangue and clay shale were characterized by analytical techniques such as X-ray diffraction (XRD) and X-ray fluorescence analysis (XRF). The optimal calcining temperature of coal gangue and clay shale was obtained through differential thermal analysis (DTA), and the activity evaluation method was conducted to get the optimal calcining procedure. The results showed that, the optimal calcining procedure for coal gangue and clay shale to obtain the best pozzolanic activity is as following: coal gangue and clay shale under the ratio of 7:3 were calcined at 780 °C for 2 h, and then quickly cooled in the air. The cementitious materials, which were prepared by calcining coal gangue, clay shale, slag, gypsum and CaO (as activator) under the ratio of 45:35:5:15, could reach the strength of class P.C. 32.5 of the Chinese standard GB175-2007.

We report on multicolor and near-infrared electroluminescence (EL) from the devices using rare-earth doped TiO2 (TiO2:RE) films as light-emitting layers, which are ascribed to the impact excitation of RE3+ ions, with the EL onset voltages below 10 V. The devices are in the structure of ITO/TiO2:RE/SiO2/Si, in which the SiO2 layer is ∼10 nm thick and RE includes Eu, Er, Tm, Nd, and so on. With sufficiently high positive voltage applied on the ITO electrode, the conduction electrons in Si can tunnel into the conduction band of SiO2 layer via the trap-assisted tunneling mechanism, gaining the potential energy ∼4 eV higher than the conduction band edge of TiO2. Therefore, as the electrons in the SiO2 layer drift into the TiO2:RE layer, they become hot electrons. Such hot electrons impact-excite the RE3+ ions incorporated into the TiO2 host, leading to the characteristic emissions.