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In this paper, a new hybrid scheme which combines radial basic function (RBF) neural network with a model following sliding mode control technique to take their common features is used to solve attitude control problem of gliding guide projectile. The attitude kinematics model described by second-order nonlinear uncertain system is divided into two single-input single-output subsystems by considering the nonlinearity as disturbance. To avoid generating high control value, the coupled inputs are kept as one nominal input instead of being included in lumped uncertainties. The uncertainties in the plant are cancelled by an adaptive RBF neural networks estimator, which is designed based on Lyapunov theory. To verify the effectiveness of the proposed control strategy, attitude tracking control experiments are simulated under strong internal and external disturbances.

In this article, the problem of the event-triggered optimal control for a class of strict-feedback nonlinear systems with external disturbances is investigated. First, by introducing proper low-pass filters to the steps of backstepping design, the problem of “jump of the error surfaces” is avoided. What is more, it facilitates the design of a fuzzy hybrid-mode-triggered feedforward controller, which aims to transform the original controlled nonlinear strict-feedback system into an equivalent nonlinear system in affine form. Second, by utilizing the adaptive dynamic programming theory, an event-triggered feedback controller is developed for the equivalent affine nonlinear system. Differing from the existing methods, the real control input consists of two event-triggered terms, which can be updated synchronously under the proposed composite error-based triggering condition. Moreover, it is proven that all the closed-loop signals are bounded. At last, by taking a second-order nonlinear system and missile integrated guidance and control system as examples, simulation results demonstrate the effectiveness of the proposed approach.

Lithium (Li) metal is the most promising anode for improving the energy density of currently commercialized Li-ion batteries. However, its practical application is limited due to its high reactivity to electrolytes, which induces severe electrolyte decomposition and Li-dendrite growth. Interphases are usually constructed on Li anode to address the above issue. Meanwhile, it is a big challenge to balance the stability and plating/stripping overpotential of Li anode. In this work, we report a novel strategy for constructing a highly stable and lowly polarized surface film on Li anode. A chemically and structurally unique film is formed by simply dropping a zinc trifluoromethanesulfonate [Zn(OTF)2] and fluoroethylene carbonate (FEC)-containing solution onto Li anode. This unique film consists of inner nucleation sites and outer protection textures, mainly containing Li-Zn alloy and LiF/polymer, respectively. The former results from the preferential reduction of Zn(OTF)2, providing nucleation sites with low polarization for Li plating/stripping. In contrast, the latter arises from the subsequent reduction of FEC, providing protection for the underneath Li-Zn alloy and Li metal and ensuring the stability of Li anode. The Li anode with such a unique surface film exhibits excellent cycling stability and low plating/stripping overpotentials, which have been demonstrated using Li//Li symmetric and Li//LiFePO4full cells.

Quasi-1D titanium trisulfide (TiS3) has strong in-plane anisotropy with a direct band gap of about 1 eV, which has attracted wide attention in the fields of microelectronics and optoelectronics. However, the investigation of in situsynthesis, synthetic mechanism, and nonlinear optical properties of TiS3is rarely reported. In this work, we developed a transfer-free method to grow TiS3nanoribbons, successfully reducing the synthesis time from a few days to less than 24 h without pretreatment. Raman spectroscopy revealed TiS3was not directly synthesized by titanium (Ti) and sulfur (S) but by the further sulfurization reaction of intermediate product TiS2. Moreover, the polarized four-wave mixing (FWM) imaging of the as-grown TiS3samples was conducted by ultrafast nonlinear optical spectroscopy for the first time, identifying the crystal axis orientation of TiS3accurately and quickly. Our work not only provides a rapid growth method for transfer-free synthesis of TiS3nanoribbons on SiO2/Si substrates but also investigate the fast and non-destructive ultrafast nonlinear optical characterization of quasi-1D TiS3, which lays a foundation for understanding the synthetic mechanism and physicochemical properties of transition metal trisulfides (TMTCs) and promoting the functional device applications of TMTCs represented by TiS3.

AbstractVarious policy initiatives have been launched to spur innovation in China. They include pilot cities, self-dependent demonstration areas, and comprehensive reform zones. By reviewing the policy formulation processes of these initiatives, we describe the distinct features of experimentalist governance in China. And, we add to policy process theory by analyzing their authority distribution, strategic objectives, and policy goals and instruments. China’s pursuit of its innovation strategy has caused three experimentalist governance patterns to emerge. The cities explore policy alternatives through adaptive reconciliation. The regions test policy instruments through selective recognition. And, the central government uses hierarchical experimentation to deploy its policy frameworks. Through the temporal and spatial interactions of China’s multilevel governments, these patterns have shaped a progressive approach to the formation (or reformation) of the nation’s innovation policy.

This paper presents a novel robust optimal acceleration autopilot design for the gliding-guided projectile. First, the coupling input amplitude and rate saturation problem is analyzed, and an algorithm is developed to obtain the admissible nominal control inputs. Then, by utilizing backstepping technique and the uncertainty and disturbance estimator, a robust feedforward controller is raised to reduce the tracking control problem of the nonlinear system into an equivalent optimal stabilization issue of a linear system, which facilitates the design of a linear quadratic regulator (LQR) based feedback controller. Finally, the stability of the whole system is proved based on Lyapunov theory. Simulations are conducted to demonstrate the effectiveness of the proposed control strategy.

High energy density lithium-ion batteries using Ni-rich cathode (such as LiNi0.6Co0.2Mn0.2O2) suffer from severe capacity decay. P-toluenesulfonyl fluoride (pTSF) has been investigated as a novel film-forming electrolyte additive to enhance the cycling performances of graphite/LiNi0.6Co0.2Mn0.2O2pouch cell. In comparison with the baseline electrolyte, a small dose of pTSF can significantly improve the cyclic stability of the cell. Theoretical calculations together with experimental results indicate that pTSF would be oxidized and reduced to construct protective interphase film on the surfaces of LiNi0.6Co0.2Mn0.2O2cathode and graphite anode, respectively. These S-containing surface films derived from pTSF effectively mitigate the decomposition of electrolyte, reduce the interphasial impedance, as well as prevent the dissolution of transition metal ions from Ni-rich cathode upon cycling at high voltage. This finding is beneficial for the practical application of high energy density graphite/ LiNi0.6Co0.2Mn0.2O2cells.

High-voltage cathodes provide a promising solution to the energy density limitation of currently commercialized lithium-ion batteries, but they are unstable in electrolytes during the charge/discharge process. To address this issue, we propose a novel electrolyte additive, pentafluorophenyltriethoxysilane (TPS), which is rich in elemental F and contains elemental Si. The effectiveness of TPS has been demonstrated by cycling a representative high-voltage cathode, LiNi0.5Mn1.5O4(LNMO), in 1.0 M LiPF6–diethyl carbonate/ethylene carbonate/ethyl methyl carbonate (2/3/5 in weight). LNMO presents an increased capacity retention from 28 to 85% after 400 cycles at 1 C by applying 1 wt % TPS. Further electrochemical measurements combined with spectroscopic characterization and theoretical calculations indicate that TPS can not only construct a robust protective cathode electrolyte interphase via its oxidation during initial lithium desertion but also scavenge the detrimental hydrogen fluoride (HF) present in the electrolyte via its strong combination with the species HF, F–, and H+, highly stabilizing LNMO during the charge/discharge process. These features of TPS provide a new solution to the obstacle in the practical application of high-voltage cathodes not limited to LNMO.

In recent years, messenger RNA (mRNA) vaccines have exhibited great potential to replace conventional vaccines owing to their low risk of insertional mutagenesis, safety and efficacy, rapid and scalable production, and low‐cost manufacturing. With the great achievements of chemical modification and sequence optimization methods of mRNA, the key to the success of mRNA vaccines is strictly dependent on safe and efficient gene vectors. Among various delivery platforms, non‐viral mRNA vectors could represent perfect choices for future clinical translation regarding their safety, sufficient packaging capability, low immunogenicity, and versatility. In this review, the recent progress in the development of non‐viral mRNA vectors is focused on. Various organic vectors including lipid nanoparticles (LNPs), polymers, peptides, and exosomes for efficient mRNA delivery are presented and summarized. Furthermore, the latest advances in clinical trials of mRNA vaccines are described. Finally, the current challenges and future possibilities for the clinical translation of these promising mRNA vectors are also discussed. This review has focused on up‐to‐date development of non‐viral vectors for mRNA Vaccine. The advantages and disadvantages of various mRNA vector are commented and discussed. Meanwhile, the ongoing clinical trials of various mRNA vector are also summarized. The prospect of clinical transformation of various mRNA vectors are highlighted.

Purpose: Raltitrexed shows therapeutic effects and safety in many types of malignant tumors. However, reports of the clinical outcomes of raltitrexed-based transarterial chemoembolization (TACE) or drug-eluting beads TACE (DEB-TACE) in the treatment of hepatocellular carcinoma (HCC) are rare. We aim to report the preliminary outcomes of DEB-TACE loaded with raltitrexed in patients with unresectable or recurrent HCC. Methods: From June 2018 to March 2020, 29 patients with unresectable or recurrent HCC were recruited from our department and treated by DEB-TACE loaded with raltitrexed. Overall survival and progression-free survival were the primary end points. Tumor response was investigated by using the modified response evaluation criteria in solid tumors (mRECIST) criteria. Results: A total of 49 sessions of DEB-TACE were performed, with a technique success rate of 100%. The overall response rate and disease control rate at 1, 3, and 6 months after DEB-TACE were 72.0% and 96.0%, 57.1% and 85.7%, 47.6% and 66.7% respectively. The median progression-free survival and overall survival was 25.7 and 33.9 months, respectively. The 6-, 24- and 36-month overall survival rates were 88.4%, 66.3% and 46.3%, respectively. Minor complications were observed in 17 patients (58.6%), with no treatment-related mortality or severe adverse events. The most common treatment-related complications were abdominal pain (41.4%) and elevated ALT/AST (27.6%). Conclusion: DEB-TACE loaded with raltitrexed is suggested as a safe, feasible, efficacious palliative regimen in unresectable or recurrent HCC patients.

Luminogens with aggregation‐induced emission characteristics (AIEgens) are considered good options for two‐photon (2P) probes, owing to their flexibility of design, heavy‐metal‐free composition, and resistance to photobleaching. However, the design principles for large 2P absorption cross‐section (δ) generally require high coplanarity, strong donor–acceptor (D‐A) interactions, and long conjugation, which can severely weaken the brightness of AIEgens at the aggregated state and undermine their potential in 2P fluorescence imaging (2PFI). Exploration of a feasible approach to overcome the “Buckets Effect” of AIEgen‐based 2P probes is thus a fascinating yet challenging task. Herein, an AIEgen, namely (Z)‐2‐(4‐aminophenyl)‐3‐(5‐(4‐(bis(4‐methoxyphenyl)amino)phenyl)thiophen‐2‐yl)acrylonitrile (MTAA) is designed to have a big δ according to the calculation result and a low fluorescence quantum yield (QY) of 2.2% in dimethyl sulfoxide (DMSO). Impressively, upon integrating into bovine serum albumin (BSA), the protein‐sized MTAA@BSA dots exhibit a 25‐fold higher fluorescence QY compared to MTAA molecules, contributing to an imaging depth of 818 µm in the brain vasculature. The retention and clearance of MTAA@BSA dots in the liver and kidney are also studied using 2PFI. Overall, this work provides a facile approach to overcome the “Buckets Effect” of AIEgen to generate highly efficient, reliable, and biocompatible 2P probes. The “Buckets Effect” of two‐photon AIEgen probes, low fluorescence quantum yield, is smartly addressed by integrating AIEgens into the bovine serum albumin. Taking advantage of the highly enhanced brightness and highly biocompatible nature, MTAA@BSA dots not only exhibit good performance in two‐photon fluorescence imaging but also have negligible safety concerns.

A design of coaxial hollow nanocables of carbon nanotubes and silicon composite (CNTs@Silicon) was presented, and the lithiation/delithiation behavior was investigated. The FIB-SEM studies demonstrated hollow structured silicon tends to expand inward and shrink outward during lithiation/delithiation, which reveal the mechanism of inhibitive effect of the excessive growth of solid–electrolyte interface by hollow structured silicon. The as-prepared coaxial hollow nanocables demonstrate an impressive reversible specific capacity of 1150 mAh g–1over 500 cycles, giving an average Coulombic efficiency of >99.9%. The electrochemical impedance spectroscopy and differential scanning calorimetry confirmed the SEI film excessive growth is prevented.

ObjectivesEarly placement of transjugular intrahepatic portosystemic shunt (TIPS) has been shown to improve survival in high-risk patients (Child-Pugh B plus active bleeding at endoscopy or Child-Pugh C 10–13) with cirrhosis and acute variceal bleeding (AVB). However, early TIPS criteria may overestimate the mortality risk in a significant proportion of patients, and the survival benefit conferred by early TIPS in such patients has been questioned. Alternative criteria have been proposed to refine the criteria used to identify candidates for early TIPS. Nevertheless, the true survival benefit provided (or not) by early TIPS compared with standard treatment in the different risk categories has not been investigated in specifically designed comparative studies.DesignWe collected data on 1425 consecutive patients with cirrhosis and AVB who were admitted to 12 university hospitals in China between December 2010 and June 2016. Of these, 206 patients received early TIPS, and 1219 patients received standard treatment. The Fine and Gray competing risk regression model was used to compare the outcomes between the two groups that were stratified based on the currently available risk stratification systems after adjusting for liver disease severity and other potential confounders.ResultsOverall, early TIPS was associated with an 80% relative risk reduction (RRR) in mortality at 6 weeks (adjusted HR=0.20; 95% CI: 0.10 to 044; p<0.001) and 51% RRR at 1 year (adjusted HR=0.49, 95% CI: 0.32 to 0.73; p<0.001) compared with standard treatment. In stratification analyses, the RRRs in mortality did not significantly differ among the risk categories. However, the absolute risk reductions (ARRs) of mortality were more pronounced in high-risk patients. The ARRs at 6 weeks were −2.1%, −10.2% and −32.4% in Model for End-stage Liver Disease (MELD) ≤11, 12–18 and ≥19 patients and were −1.5%, −9.1% and −23.2% in Child-Pugh A, B and C patients, respectively (interaction tests, p<0.001 for both criteria). The ARRs for mortality at 1 year were −1.7%, −5.4% and −32.7% in MELD ≤11, 12–18 and ≥19 patients, respectively, and −3.6%, −5.2% and −20.3% in Child-Pugh A, B and C patients, respectively (interaction tests, p<0.001 for both criteria). After adjusting for liver disease severity and other potential confounders, a survival benefit was observed in MELD ≥19 or Child-Pugh C patients but not in MELD ≤11 or Child-Pugh A patients. In MELD 12–18 patients, a survival benefit was observed within 6 weeks but not at 1 year. In Child-Pugh B patients, a survival benefit was observed in those with active bleeding but not those without active bleeding. However, the evaluation of active bleeding was associated with a high interobserver variability. Furthermore, early TIPS was associated with a significantly reduced incidence of failure to control bleeding or rebleeding and new or worsening ascites, without increasing the risk of overt hepatic encephalopathy.ConclusionsEarly TIPS was associated with improved survival in patients with MELD ≥19 or Child-Pugh C cirrhosis but not in patients with MELD ≤11 or Child-Pugh A cirrhosis. For MELD 12–18 or Child-Pugh B patients, future studies addressing optimal selection criteria for early TIPS remain highly warranted.

Low-salt concentration ether-based electrolyte constructed Discontinuous-SEI to maximized the capacity of Hard carbon anode.

NaCl–MgCl2–CaCl2eutectic ternary chloride salts are potential heat transfer and storage materials for high-temperature thermal energy storage. In this study, first-principles molecular dynamics simulation results were used as a data set to develop an interatomic potential for ternary chloride salts using a neural network machine learning method. Deep potential molecular dynamics (DPMD) simulations were performed to predict the microstructure and thermophysical properties of the NaCl–MgCl2–CaCl2ternary salt. This work reveals that DPMD simulations can accurately calculate the microstructure and thermophysical properties of ternary chloride salts. The association strength of chloride ions and cations follows the order of Mg2+> Ca2+> Na+, and the coordination number decreases gradually with increasing temperature, indicating a progressively looser and more disordered molten structure. Furthermore, thermophysical properties, such as density, specific heat capacity, thermal conductivity, and viscosity, are in good agreement with the experimental measurements. Machine learning molecular dynamics will provide a feasible multivariate molten salt exploration method for the design of next-generation solar power plants and thermal energy storage systems.

Soft sensing models of the desulfurization process are developed in a circulating fluidized bed (CFB) boiler that can capture sulfur dioxide (SO2) with the limestone sorbent in the furnace. First, calcining utilization of CaCO3and sulfating utilization of CaO are proposed by mechanism analysis of the theoretical air and flue gas, and the online prediction method is achieved by using an adaptive-tree-structure-based fuzzy inference system (ATSFIS). Second, condition monitoring models of active CaCO3, active CaO, and soft sensing model of SO2emissions are studied by using the experimental data of a CFB boiler in China, which can monitor the storage and condition of the limestone in the furnace and predict SO2emissions. Finally, a nonlinear proportional–integral–derivative (PID) control system based on the above models is designed to control the feed rate of limestone for the reduction of SO2emissions. The simulation results show that the soft sensing models are consistent with the mechanism test results and can accurately predict SO2emissions. The control system of limestone is also proven to be effective.

Molecular disease mechanisms typically constitute abnormalities in the regulation of genes producing many kinds of alterations in the expression levels. To identify disease-altered genes better, we have developed an approach that searches for the genes which present a significant rank alteration in the rank of their expression profiles, by comparing an altered rank with another gene. The approach provides groups of genes and assigns a statistical measure of significance to each pair of genes selected. The method is evaluated using two experimental sets of microarrays. We investigated the possibility of inferring the rank reverse pairs and its possibility in diagnostic application when there is no prior knowledge of the genes belonging to disease, nor about the structure of gene regulatory network. We also show that rank reverse is a very powerful technique to diagnostic disease in the practical application and could be used prior to traditional biomarker discovery.

Two-dimensional (2D) material photodetectors have received considerable attention in optoelectronics as a result of their extraordinary properties, such as passivated surfaces, strong light–matter interactions, and broad spectral responses. However, single 2D material photodetectors still suffer from low responsivity, large dark current, and long response time as a result of their atomic-level thickness, large binding energy, and susceptibility to defects. Here, a transition metal trichalcogenide TiS3with excellent photoelectric characteristics, including a direct bandgap (1.1 eV), high mobility, high air stability, and anisotropy, is selected to construct a type-II heterojunction with few-layer MoS2, aiming to improve the performance of 2D photodetectors. An ultrahigh photoresponsivity of the TiS3/MoS2heterojunction of 48 666 A/W at 365 nm, 20 000 A/W at 625 nm, and 251 A/W at 850 nm is achieved under light-emitting diode illumination. The response time and dark current are 2 and 3 orders of magnitude lower than those of the current TiS3photodetector with the highest photoresponsivity (2500 A/W), respectively. Furthermore, polarized four-wave mixing spectroscopy and polarized photocurrent measurements verify its polarization-sensitive characteristics. This work confirms the excellent potential of TiS3/MoS2heterojunctions for air-stable, high-performance, polarization-sensitive, and multiband photodetectors, and the excellent type-II TiS3/MoS2heterojunction system may accelerate the design and fabrication of other 2D functional devices.

Purpose. The goal of this study was to assess the clinical efficacy and safety of the arsenic trioxide (ATO)/lipiodol emulsion in the transcatheter arterial chemoembolization (TACE) combined with apatinib in the treatment of advanced hepatocellular carcinoma (HCC). Methods. From December 2015 to February 2017, a total of 87 patients were consecutively enrolled and underwent ATO-TACE (aTACE) combined with apatinib in the treatment of advanced HCC. The treatment response and adverse events were assessed at the first month and third month after aTACE therapy. Progression-free survival (PFS), overall survival (OS), and treatment-related adverse events were also analyzed. Results. 87 patients (57 men; 30 women) were enrolled in the present study. Compared to that at the pre-aTACE examination, the levels of AST and ALT were elevated at the first week after procedure (65.84 U/L ± 22.93 U/L vs. 54.15 U/L ± 19.60 U/L, p=0.032; 63.44 U/L ± 22.50 U/L vs. 51.60 U/L ± 13.89 U/L, p=0.027, respectively). Most of the adverse events were grade 1 or 2 according to National Cancer Institute Common Terminology Criteria for Adverse Event (CTCAE). Of the exception, 4 persons (2%) did have grade 3 hand-foot skin reactions, 1 (1%) had grade 3 diarrhea, 1 (1%) had grade 3 hypertension, and 3 (3%) had grade 3 proteinuria and forced to reduce the dose of apatinib by half. The survival analysis of the combination with aTACE and apatinib therapy found that the median PFS was 10.2 months (95% CI: 8.543–11.857), and the median OS was 23.300 months (95% CI: 20.833–25.767). Additionally, both univariate and multivariate Cox regression revealed that the tumor burden (≤50%) and the patients without portal vein tumor thrombus (PVTT) significantly impacted the patient’s PFS and OS and were related to better survival. Conclusion. aTACE combined with apatinib is a safe and promising treatment approach for patients with advanced HCC. Additionally, tumor burden (≤50%) and the patients without PVTT are associated with better PFS and OS.

This paper presents a robust repetitive control (RC) design applied to three-dimensional homing guidance of missiles with impact angle constraint. The proposed guidance law is substantially a composite control method, which is constructed through a combination of RC and sliding mode control. More specifically, the RC exerts advantages to drive the state tracking error converge to zero, then sliding mode control is triggered, making the system be robust in terms of noise and disturbance. The effectiveness of the proposed guidance law is validated through simulation.

Aerodynamic damping and bend–twist coupling significantly affect the dynamic response of wind turbines. In this paper, unsteady aerodynamics, aerodynamic damping, and bend–twist coupling (twist-towards-feather) are combined to establish a smart rotor model with trailing edge flaps (TEFs) based on a National Renewable Energy Laboratory (NREL) 5 MW reference horizontal-axis wind turbine. The overall idea is to quantitatively evaluate the influence of aerodynamic damping and bend–twist coupling on the smart rotor and to present the control effect of the TEFs under normal wind turbine operating conditions. An aerodynamic model considering the dynamic stall and aerodynamic damping as well as a structural bend–twist coupling model with the influence of gravity and centrifugal force are incorporated into the coupling analysis. The model verification shows that the present model is relatively stable under highly unsteady wind conditions. Then, a robust adaptive tracking (RAT) controller is designed to suppress fluctuations in both the flapwise tip deflection and output power. The simulations show an average reduction of up to 63.86% in the flapwise tip deflection power spectral density (PSD) of blade 1 at the 1P frequency, with an average reduction in the standard deviation of the output power of up to 34.33%.

Traditional spectroscopic analysis based on the Beer-Lambert law cannot analyze the analyte with high concentration and interference between different compositions, such as the electrolyte in vanadium redox flow batteries (VRBs). Here we propose a new method for online detection of such analytes. We demonstrate experimentally that, by comparing the transmittance spectrum of the analyte with the spectra in a preprepared database using our intensity-corrected correlation coefficient (ICCC) algorithm, parameters such as the state of charge (SOC) of both the positive and the negative electrolytes in the VRB can be online monitored. This method could monitor the level of the electrolytes imbalance in the VRB, which is useful for further rebalancing the electrolyte and restoring the capacity loss of the VRB. The method also has the potential to be used in the online detection of other chemical reactions, in which the chemical reagents have high concentration and interferences between different compositions.