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To further improve the application quality of the waterborne epoxy resin (WER) in road engineering, a variety of WER and polyurethane-modified WER were prepared. The WER was treated by acid solution immersion, alkali solution immersion, salt solution immersion, oil immersion or artificial-accelerated aging. The mechanical properties of the WER before and after the treatment by various methods were tested. Based on the ideal point method of entropy weight, the influence degree of each treatment method on the mechanical properties of the WER was analysed, and the mechanical properties decay and residual mechanical properties of the WER were evaluated. The bonding durability of the WER was analysed. The results show that after the xenon lamp aging treatment, the mechanical properties of the WER decreased most significantly. The mechanical durability of the WER modified by polyurethane is improved to a certain extent, and the retention rates of their mechanical properties are >85%. After treatment by various corrosion or aging methods, the retention rates of mechanical properties of the PUE-E44 WER are >89.29%, showing an improved corrosion and aging resistance. The residual mechanical and bonding properties of the PUD-E51 WER are at a high level, and still show improved mechanical and bonding properties. [ABSTRACT FROM AUTHOR]

The purpose is to clarify the development law of mechanical properties of waterborne epoxy resin coatings at low temperatures and further promote its application in cold areas. Different types of polyurethane-modified waterborne epoxy resins were prepared. The development law of low-temperature mechanical properties of waterborne epoxy resin at different curing time was studied systematically. The improvement effect of polyurethane on the mechanical properties of waterborne epoxy resin at low temperatures was evaluated. The prediction models of low-temperature mechanical properties of waterborne epoxy resin based on Grey–Markov chain method was established. The results show that the mechanical properties of waterborne epoxy resin decrease after low-temperature treatment for 15 days. Its strength and flexibility are reduced by 3% and 10%. Polyurethane could improve the low-temperature durability of waterborne epoxy resin. The retention rates of the various mechanical properties of modified waterborne epoxy resin increase significantly. Among them, the retention rate of elongation at break increases by more than 50%, and the bending deformation is almost no longer attenuated. The prediction model based on BP–Elman neural network has a higher accuracy, and the relative error is less than 0.04%. [ABSTRACT FROM AUTHOR]

Due to the propagation of traffic congestion from upstream to downstream links and the uncertainty of path choice behaviours, travel times between different links, particularly adjacent links, are highly correlated in a typical period from day to day. To improve the estimation accuracy of both the mean and covariance of link travel times, a novel measurement is proposed to optimize the locations of multi-type traffic sensors for link travel time estimation. Multi-source data from different types of traffic sensors can be integrated to better estimate link travel time in an entire road network. In practice, the allocation of multi-type traffic sensors is constrained by the total financial budget and should be optimized in accordance with measurement errors and the cost ratio. Numerical examples of synthetic and real road networks are conducted to demonstrate the applications and merits of the proposed multi-type sensor location model with covariance effects. [ABSTRACT FROM AUTHOR]

A series of 1-[2-(4-methyl-2-(methylthio)pyrimidine-5-carboxamido)phenyl]ethyl-substitutedphenyl carbamates (3a–3i) were designed and synthesized, using 4-methyl-2-(methylthio)pyrimidine-5-carboxylic acid, (2-aminophenyl)ethan-1-one, and substituted phenyl isocyanates as starting materials. Their structures were characterized by 1H NMR, 13C NMR, IR and HRMS. The in vitro fungicidal activities against Sclerotinia sclerotiorum were evaluated, and the result showed that some compounds displayed moderate antifungal activity with >60% inhibitory rates, among which 1-[2-(4-methyl-2-(methylthio)pyrimidine-5-carboxamido)phenyl] ethyl-(2- methyl phenyl)carbamate (3a) and 1-[2-(4-methyl-2-(methylthio)pyrimidine-5- carboxamido)phenyl] ethyl-(3-trifluoromethyl phenyl)carbamate (3g) held inhibitory rates of 69.5% and 70.3% at 100 mg/L, respectively. Molecular docking study showed that 3g can form two hydrogen bonds and a cation-π interaction with succinate dehydrogenase. [ABSTRACT FROM AUTHOR]

Friction drive and wear control is a tough issue for linear standing-wave ultrasonic motors with intermittent contact and impact friction. For the widely recognized reduction of friction/wear, minimum quantity lubrication was adopted to improve the output performances and services for motors through friction regulation. Given different preload and driving voltages, the mechanical characteristics of motors with minimal quantity lubrication were investigated using a homemade test rig. Results show that output performances and driving efficiency under film lubrication differ from those of dry friction. The optimized driving voltage was reduced by 31.5% and the minimum startup voltage was reduced by 41.67% using film lubrication. Additionally, the output speed increased by 26.29%, and thrust decreased by 41.26% under uniform exciting conditions (e.g., 150 V at 39.14 kHz). The existence of film lubrication broadens the effective frictional contact boundary, and effective friction contribution enhances the driving efficiency (the maximum efficiency of motors increased by 14%). Furthermore, the singularity of the effect of preload is significantly improved after lubrication, and the friction interface of the stator/slider becomes more controllable. Suitable lubrication is critical to the improvement of startup performance and prone to realize low-voltage driving, and the combination of lubrication regulation and wear inhibition is conducive to the durability and reliability of motors. This study provides an additional alternative for performance improvement of linear standing-wave motors apart from frictional materials. [ABSTRACT FROM AUTHOR]

Taraxasterol (TAL) is a pentacyclic triterpenoid compound, which has anti-inflammatory effect. Cytotoxicity assay was used to determine the optimal concentration of TAL and positive control dipotassium glycyrrhizinate (DG), and the optimal dose of UVB. Experimental data indicate that TAL has scavenging activity against UVB radiation-induced intracellular reactive oxygen species (ROS) compared to UVB controls. The contents of skin barrier-related factors in the groups were detected by Enzyme-linked immunosorbent assay (ELISA), then ELISA and quantitative polymerase chain reaction (qPCR) were used to detect changes in the inflammatory factors, apoptosis factors, and gene levels in the groups. Therefore, TAL stabilised the levels of inflammation, apoptosis, and skin barrier-related factors by regulating Mitogen-activated protein kinases/nuclear factor-k-gene binding (MAPK/NF-κB) signalling pathways, such as jun-amino-terminal kinase (JNK), p38, extracellular signal-regulated kinase (ERK), and NF-κB. These results suggest that TAL repairs UVB-induced skin barrier damage by scavenging reactive oxygen species and regulating the MAPK/NF-κB signalling pathway. [ABSTRACT FROM AUTHOR]

To ensure the effective bonding of each structural layer of pavement and improve the service quality and durability of pavement, the waterborne epoxy resin (WER) emulsified asphalt (WEREA) tack coat binders were prepared by using polyurethane-epoxy resin. The basic properties of WEREA, such as tensile strength, adhesion to aggregate, high temperature heat resistance and low temperature impact resistance were studied. Its composition and ratio were optimised. The waterproof, bonding and durability performance of WEREA used in pavement tack coat were evaluated. The results show that WEREA prepared by polyether polyurethane modified E-51 epoxy resin (PUD-E51) has higher early and late strength. Its tensile strength was 1.75 MPa after curing for 7 days. The basic properties of WEREA, including adhesion to aggregate, heat resistance and impact resistance were better than those of SBS modified asphalt and crumb rubber modified asphalt binder. The tack coat of WEREA cannot seep under the dynamic water pressure of 0.6 MPa for 30 min. According to the interlaminar shear strength, the recommended spraying amount of the WEREA tack coat was 1.0 kg/m2. The WEREA could guarantee the effective bonding of each structural layer of the pavement, and improve the durability of the tack coat and pavement. [ABSTRACT FROM AUTHOR]

The purpose of the study is to clarify the curing effect of raw material composition on waterborne epoxy resin, thereby further improving working performance of waterborne epoxy resin. Based on the preferred variety of epoxy resins and curing agents, different types of waterborne epoxy resins were prepared. The effects of different raw material compositions on the physical properties of waterborne epoxy resin were studied systematically. The reasonable material composition and proportion were determined. The influence of physical properties of waterborne epoxy resin on its adhesion properties was evaluated. The results show that raw material composition has a large impact on the working performance of waterborne epoxy resin. The combination of E–44 waterborne epoxy resin and alicyclic amine has the best comprehensive property. And it is 3.65–36.22% higher than other combinations. The adhesive property index of waterborne epoxy resin has a high correlation with the mechanical property index, and they are in direct proportion. [ABSTRACT FROM AUTHOR]

This paper investigates the optimal synchronisation problem for unknown nonlinear heterogeneous multi-agent systems (MASs) with an active leader and disturbances. Due to the external input signal of the active leader, the resulted uncooperative behaviours and unpredictability increase difficulty to derive the analytical solution of the coupled Bellman equation. To this end, we develop a distributed model reference adaptive critic learning algorithm with a hierarchical and distributed synchronisation control framework, which transforms the synchronisation problem of unknown nonlinear MASs into that of defined reference ones. Moreover, the algorithm extends our previous work to the distributed MASs, so that it is guaranteed that all the agents reach an agreement with the minimised transient errors and robustness against the disturbances and the neural network (NN) approximation errors. It is proved that the local neighbour tracking errors and the NN weight estimation errors are uniformly ultimately bounded via Lyapunov stability theory. A simulation example for multi-manipulator systems demonstrates the effectiveness of the algorithm. [ABSTRACT FROM AUTHOR]

Cyclin-dependent kinases (CDKs) are hyperactive in many cancers and have served as cancer therapeutic targets for decades. Palbociclib (Palb) is the first approved CDK4/6 inhibitor to treat hormone receptor (HR)-positive, HER2-negative advanced breast cancer. Acquired drug resistance is one obstacle of Palb be utilized in other cancer. CDK2 compensation of CDK4/6 loss is one of the causes that cancer cells are resistant to Palb. Hence, targeting multiple CDKs could be a novel strategy to prevent the drug resistance of cancer cells and expand the application of Palb in other cancer. In this study, we initially indicated Polyphyllin I (PPI) significantly inhibits non-small lung cancer cell (NSCLC) proliferation, promotes cell apoptosis in vitro and in vivo. Mechanistically, PPI can inhibit Rb through the p21/CDK2/Rb signaling pathway in NSCLC. A combination of PPI and Palb exerts a significant synergistic anti-cancer ability on NSCLC. Of note, PPI can reverse Palb drug resistance. Herein, we first time demonstrated PPI can disturb CDK2 function through upregulation of p21. The PPI effect on CDK2 provides a choice for a chemotherapeutic strategy for the elimination of NSCLC. Our study highlighted the clinical significance of simultaneously blocking of CDK2 and CDK4/6 for NSCLC treatment. [ABSTRACT FROM AUTHOR]

Tubulin polymerisation inhibitors exhibited an important role in the treatment of patients with prostate cancer. Herein, we reported the medicinal chemistry efforts leading to a new series of benzothiazoles by a bioisosterism approach. Biological testing revealed that compound 12a could significantly inhibit in vitro tubulin polymerisation of a concentration dependent manner, with an IC50 value of 2.87 μM. Immunofluorescence and EBI competition assay investigated that compound 12a effectively inhibited tubulin polymerisation and directly bound to the colchicine-binding site of β-tubulin in PC3 cells. Docking analysis showed that 12a formed hydrogen bonds with residues Tyr357, Ala247 and Val353 of tubulin. Importantly, it displayed the promising antiproliferative ability against C42B, LNCAP, 22RV1 and PC3 cells with IC50 values of 2.81 μM, 4.31 μM, 2.13 μM and 2.04 μM, respectively. In summary, compound 12a was a novel colchicine site tubulin polymerisation inhibitor with potential to treat prostate cancer. [ABSTRACT FROM AUTHOR]

The purpose is to clarify the effect of warm-mix modifier on rheological properties of SBS warm-mix modified asphalt and its viscosity reduction mechanism. Different types of SBS warm-mix modified asphalt were prepared. The effects of modifier content and temperature on the rheological properties of SBS warm-mix modified asphalt were assessed. The viscosity reduction mechanism of SBS warm-mix modified asphalt was revealed. The results show that after adding warm-mix modifier, the viscosity of SBS warm-mix modified asphalt deceased and its high-temperature performance was improved. The optimum content of warm-mix modifier is 1.0%, and the viscosity of modified asphalt reduced to 80.4–81.1%. [ABSTRACT FROM AUTHOR]

This paper concerns with a class of discrete-time linear nonzero-sum games with the partially observable system state. As is known, the optimal control policy for the nonzero-sum games relies on the full state measurement which is hard to fulfil in partially observable environment. Moreover, to achieve the optimal control, one needs to know the accurate system model. To overcome these deficiencies, this paper develops a data-driven adaptive dynamic programming method via Q-learning method using measurable input/output data without any system knowledge. First, the representation of the unmeasurable inner system state is built using historical input/output data. Then, based on the representation state, a Q-function-based policy iteration approach with convergence analysis is introduced to approximate the optimal control policy iteratively. A neural network (NN)-based actor-critic framework is applied to implement the developed data-driven approach. Finally, two simulation examples are provided to demonstrate the effectiveness of the developed approach. [ABSTRACT FROM AUTHOR]

In this paper, a glucose solution concentration measurement method is proposed based on microwave resonant cavity perturbation technique. The mathematical model of TE011 cylindrical resonator in terms of solution concentration is derived. The optimal geometry of cavity is determined by high frequency structure simulator. A brass cavity with a PVC capillary tube is produced in this study. A microwave measurement system consisting of resonator, waveguide and network analyzer is constructed to measure glucose concentrations from 70 to 150 mg/dl, using frequency range 7.539-7.546 GHz. Statistical results indicate that the resonant frequency of solution increases linearly as glucose concentration increases. Frequency shift slope (FSS) of experiment is in good accordance with the FSS of theoretical calculation, which shows the feasibility and accuracy of the method. [ABSTRACT FROM AUTHOR]

In many industrial drying processes, water is evaporated in the drying section by a large volume of fresh air supply, which contains a large amount of sensible and latent heat. Recovering heat and water from the dryer exhaust is a potential way to realize energy and water conservation in drying systems. In this paper, the experimental and theoretical investigations of the waste heat and water recovery characteristics of heat exchangers for dryer exhaust are presented. A hot air and water vapor mixture was used to simulate dryer exhaust. Convection-condensation heat transfer and water recovery characteristics were first obtained under various water vapor mass fractions, flow velocities, and humid air inlet temperatures through experiments, which revealed that the convection-condensation heat transfer coefficient increased with the increase in water vapor mass fraction and humid air velocity, and decreased with the increase in inlet temperature. The condensed water rate increased with the increase in water vapor mass fraction and humid air velocity, while inlet temperature had almost no effect on it. The condensing ratio decreased with the increase in water vapor mass fraction and humid air velocity, while improving the inlet temperature slightly reduced it. Then, a theoretical calculation model was developed to predict the heat and water recovery characteristics of heat exchangers under a wide working condition. In this model, the pipe and suction effects caused by condensation on the tube wall were considered. The properties of humid air were changed according to the temperature and vapor content instead of regarding them as constant values. The calculation results were compared with the present experimental data and those of previous studies. The good prediction accuracy and the universality of the present model were verified. This study is of great significance to the design of heat exchangers. [ABSTRACT FROM AUTHOR]

Context: Nanoparticles (NPs) have been widely used as carriers to deliver siRNA and chemotherapeutic agents. Bcl-2 siRNA has been widely used to induce cancer cell apoptosis, and doxorubicin (Dox) can destroy cancer cells by binding with cancer cell DNA. Objective: To investigate the therapeutic effect on lung cancer of simultaneously delivering Dox and Bcl-2-siRNA using epidermal growth factor (EGF) modified monomethoxy (polyethylene glycol)-poly (D, L-lactide-co-glycolide)-poly(L-lysine) (mPEG-PLGA-PLL, PEAL) NPs (EGF-PEAL). Methods: EGF-PEAL NPs were characterized with respect to size, zeta potential and morphology. Cytotoxicity and drug (or siRNA) loading capacity of EGF-PEAL NPs were analyzed. Cellular uptake, drug release profile, cell killing effects of Dox and Bcl-2-siRNA-loaded EGF-PEAL NPs were assessed. Biodistribution and therapeutic effects of Dox and Bcl-2-siRNA EGF-PEAL NPs were evaluated in H1299 tumor-bearing mice. Results and discussion: EGF-PEAL NPs or PEAL NPs had nearly negligible cytotoxicity toward H1299 cells. Dox and Bcl-2-siRNA gradually released from EGF-PEAL NPs and exhibited sustained release patterns. Dox and Bcl-2-siRNA-loaded NPs were taken up by cells and induced the apoptosis of H1299 cells more effectively than using Dox or Bcl-2 siRNA alone. With the intravenous injection of PEAL NPs into H1299 xenografted mice, we found that combination treatment suppressed lung cancer growth and reduced Bcl-2 expression in tumor tissue, and EGF-PEAL NPs concentrated in lung tumor much more than non-targeted PEAL NPs. Conclusion: We conclude that co-delivery of Dox and Bcl-2-siRNA by tumor-targeted EGF-PEAL NPs could significantly inhibit lung cancer growth. [ABSTRACT FROM PUBLISHER]

The early Permian Xiaomiao mafic dike swarm in the East Kunlun orogenic belt (EKOB) provides an excellent opportunity to study the petrogenesis of such swarms developed in supra-subduction zone environments, and to investigate the early plate tectonic history of the Palaeo-Tethyan Ocean. Hornblende40Ar–39Ar dating results indicate that the mafic dikes formed in the early Permian (277.76 ± 2.72 Ma). The Xiaomiao mafic hypabyssals have the following compositional range: SiO2 = 46.55–55.75%, MgO = 2.80–7.38%, Mg# = 36–61, and (Na2O + K2O) = 2.87–4.95%. Chemically, they display calc-alkali affinities, ranging in composition from gabbro to gabbroic diorite. All analysed dikes are enriched in light rare earth elements and large-ion lithophile elements (e.g. Rb and Ba), but are depleted in heavy rare earth elements and high field strength elements (e.g. Nb, Ta, and Ti). Their ISrand ϵNd(t) values range from 0.707 to 0.715 and –2.60 to +2.91, respectively. They are geochemically similar to subduction-related basaltic rocks (e.g. island arc basalt), but differ from E-MORB and N-MORB. Petrographic and major element data reveal that fractional crystallizations of clinopyroxene, olivine, hornblende, and Fe–Ti oxides may have occurred during magma evolution, but that crustal contamination was minor. Based on geochemical and Sr–Nd isotopic bulk-rock compositions, we suggest that the mafic dikes were likely generated by 10–20% partial melting of a spinel + minor garnet lherzolite mantle source metasomatized by subducted, slab-derived fluids, and minor sediments. Based on our results, we propose that the early evolution of the Palaeo-Tethyan Ocean involved the spreading and initial subduction of the Carboniferous to early Permian ocean basin followed by late Permian subduction, which generated the magmatic arc. [ABSTRACT FROM PUBLISHER]

We present new geochronological, mineralogical, geochemical, and isotopic data for recently recognized lamprophyre dikes in the East Kunlun orogenic belt of NW China. Based on euhedral amphibole phenocrysts and fine-grained, plagioclase-bearing groundmass with accessory magnetite, apatite, and titanite, these dikes are classified as spessartites. Plagioclase in these rocks is Ca-rich with An ranging from 45 to 82. Most of the amphibole phenocrysts are magnesiohastingsite or ferropargasite, with systematic ‘‘normal’ zoning in which Al2O3, CaO, and Mg# decrease from core to rim. The dikes have moderate Mg# (43–49) and high Al2O3(17.5–18.0 wt.%), FeOtotal(7.4–8.4 wt.%), and CaO (5.9–7.4 wt.%). Based on low total alkalis (Na2O + K2O = 4.2%–5.0 wt.%), most samples plot in the low-K, calc-alkaline field. They are enriched in large-ion lithophile elements (e.g. K, Rb, Sr, and Ba) and light rare-earth elements, but are depleted in high-field-strength elements (e.g. Ta, Nb, P, and Ti), and have enriched Sr-Nd-Hf isotopic compositions ((87Sr/86Sr)i = 0.70883–0.71045, εNd(t) = –5.51–5.72, εHf(t) = –4.42–0.38). Zircon U–Pb geochronology indicates that the dikes were emplaced at 253 ± 2.5 Ma and are unrelated to their granite host, which has an age of 443 ± 1.7 Ma. The geochemical and isotopic data suggest derivation from an enriched lithospheric mantle source that had been metasomatized by subduction-related fluids. Low degrees of partial melting of a phlogopite-bearing, spinel peridotite, followed by fractional crystallization of olivine, amphibole, and Ti-bearing minerals, can account for the observed geochemical features of the dikes. Trace element geochemistry and regional geology suggest that the East Kunlun lamprophryes formed in a subduction-related setting. [ABSTRACT FROM AUTHOR]