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The exact mechanism of the prothrombotic state of essential hypertension (EH) patients remains elusive. Our objective was to assess whether phosphatidylserine (PS) exposure on endothelial cells (ECs), platelets, and microparticles (MPs) can account for the hypercoagulability in EH patients. PS exposure on cells and MPs, mainly from platelets and ECs was analyzed with flow cytometry. Procoagulant activity (PCA) was evaluated by purified coagulation complex assays, clotting time, and fibrin turbidity. We found that EH patients exhibited elevated levels of PS+ platelets, serum-cultured ECs, MPs, endothelial-derived MPs and platelet-derived MPs compared to the controls (all P

Oral squamous cell carcinoma (OSCC), the subtype of head and neck cancers, is notorious for its high incidence and death rate. The role of long non-coding RNAs (lncRNAs) is discovered to be significant for the canceration and cancer progression. Long intergenic non-protein coding RNA 958 (LINC00958) is discovered as a carcinogene in multiple cancers, such as gastric cancer, pancreatic cancer, and glioma, but there has been no report about how LINC00958 functions in OSCC. The objective of our study is to unfold function and mechanism investigation on LINC00958 in OSCC. First, TCGA database showed the upregulation and prognostic significance of LINC00958 in head and neck squamous carcinoma. Then, we discovered in OSCC clinical samples that LINC00958 presented high expression and predicted poor prognosis. Also, LINC00958 was elevated in OSCC cells. In vitro gain- and loss-function experiments proved that LINC00958 facilitated cell growth, retarded apoptosis, accelerated migration, and epithelial-to-mesenchymal transition (EMT) in OSCC. Mechanistically, we confirmed the cytoplasmic expression of LINC00958 in OSCC cells, and revealed that LINC00958 sequestered miR-627-5p to upregulate YBX2 expression. Rescue assays indicated that LINC00958 regulated OSCC cell proliferation, motility and EMT through YBX2. Together, we showed that LINC00958 promoted OSCC progression through miR-627-5p/YBX2 axis, indicating LINC00958 as a new prognostic marker, and provided new perspectives for molecular targeted treatment for OSCC.

Background: Tibial plateau fracture is one of the common intra-articular fractures in clinic. And its accurate classification and treatment is a difficult problem for orthopedic surgeons. Our research aims to investigate the application value of 3D printing in the classification and preoperative planning of complex tibial plateau fractures.Methods: 28 cases of complex tibial plateau fractures diagnosed and treated in our hospital from January, 2017 to January, 2019.01 were analyzed. Preoperative spiral CT scan was performed and then DICOM data were input into the computer. We use Mimics to process data. And 3D printing technology was applied to print the 3D model of fracture (1:1). Combined with the 3D printed model, the tibial plateau fractures were subdivided into seven types according to the geometric plane of the tibial plateau. The surgical approach was determined on the 3D printed model. And then simulated operations such as accurate reduction of fracture and selection of plate placement were performed.Results: The reconstructed 3D model of tibial plateau fracture can accurately reflect the direction of fracture components displacement and the degree of plateau collapse. Also, it can help with the preoperative reconstructive plan for the tibial plateau fracture. The intraoperative fracture details were basically the same as the 3D printed model. And The fracture surface of the tibial plateau of all 28 patients was well improved in terms of restoring the anatomical structure.Conclusion: 3D printing technology can be used to guide the classification and preoperative planning of complex tibial plateau fractures.

This paper develops a closed-loop coupled fault estimation and a multivariable resilient control for high-speed train traction rectifier with upset conditions. By treating the multidimensional adverse states as changes of a single faults evolution factor, we build a reduced dimensional MIMO evolution model satisfying persistently exciting condition. In the presence of coupled faults, a nominal feed-forward controller guarantees the reliability of the closed-loop stability. Then, a fast proportional integral fault estimator is employed to predict the system resilience within a few microseconds. Under system uncertainties, a fault tolerant control scheme, including a unified robust adaptive controller, is designed to enhance the reliability. Applying the conditions of the globally asymptotically stability, the convergence of the resilient system is rigorously proved. A case study is performed to verify the effectiveness of the proposed approach.

Soldering ribbons mainly play a role in connecting electricity in photovoltaic modules. Therefore, it is of great significance to study the influence of new photovoltaic ribbons on the power of solar cells and photovoltaic modules. First, the principle of total reflection is applied to analyze and calculate the light propagation path, so as to obtain the influence mechanism of the surface structure of the photovoltaic electrode on the assembly power. Then, three types of photovoltaic modules were prepared by designing three new types of photovoltaic electrode surface structure schemes. Finally, the thermal stress and power effects of solar cells are analyzed. The results showed that the photovoltaic electrode warped during the cooling process, and the strain increased with the decrease of temperature. Under standard test conditions, the diagonal, sparse longitudinal, and dense longitudinal isomers are used as the control input parameters, and the diagonal, sparse longitudinal, and dense longitudinal isomers are used as the control input parameters. Compared with the traditional photovoltaic ribbon assembly, the output power of the new photovoltaic ribbon assembly is increased by 0.5%, 1.18% and 2%, respectively, and the optical gain of the dense vertical stripe heterogeneous ribbon is the highest.

Summary This study proposes an improved adaptive fault estimation and accommodation algorithm for a hypersonic flight vehicle that uses an interval type-2 Takagi-Sugeno fuzzy model and a quantum switching module. First, an interval type-2 Takagi-Sugeno fuzzy model for the hypersonic flight vehicle system with elevator faults is developed to process the nonlinearity and parameter uncertainties. An improved adaptive fault estimation algorithm is then constructed by adding an adjustable parameter. The quantum switching module is also applied to the estimation part to select an appropriate algorithm in different fault cases. The estimation results from the given fuzzy observer are used to design a type-2 fuzzy fault accommodation controller to stabilize the fuzzy system. The stability of the proposed scheme is analyzed using the Lyapunov stability theory. Finally, the validity and availability of the method are verified by a series of comparisons on numerical simulation results.

This study proposes a diagnosis method for IGBT open circuit fault and sensor drift fault in CRH2 through ensemble empirical mode decomposition (EEMD) and an improved kernel principal component analysis (KPCA) way. EEMD is modified to reduce noise in the current and voltage signals. Subsequently, an improved KPCA method using weight matrix to highlighting fault information is developed to detect and diagnose the composite fault. Then the three-phase current averaging method is applied to perform fault location. Numerical simulation results verify the validity and availability of the composite fault detection method.

This study proposes a novel nonlinear resilient trajectory control for a quadrotor unmanned aerial vehicle (UAV) using backstepping control and nonlinear disturbance observer. First, a nonlinear dynamic model for the quadrotor UAV that considers external disturbances from wind model uncertainties is developed. A nonlinear disturbance observer is then constructed separately from the controller to estimate the external disturbances and compensate for the negative effects of the disturbances. Based on the estimates from the given observer, a nominal nonlinear backstepping trajectory-tracking position controller is designed to stabilize the subsystems step by step until the ultimate control law is obtained. An extra term is added to the nominal controller to address the problem of actuator effectiveness loss and to ensure system resilience. The stability of the resilient controller is analyzed using Lyapunov stability theory. Simulation results are presented to demonstrate the effectiveness and robustness of the proposed nonlinear resilient controller.

This paper proposes a design method of robust fault reconstruction for a 3-DOF helicopter with actuator faults and disturbance. The model of the 3-DOF helicopter considered in this paper is an affine nonlinear system. An adaptive sliding mode observer is firstly proposed such that the actuator fault can be reconstructed through the adaptive law online. Then, based on linear matrix inequalities LMI, a feasible algorithm is explored to solve the designed parameters. Finally, a simulation study of the 3-DOF helicopter is presented to show the effectiveness of the scheme.

A reconfiguration control scheme is proposed for a quadrotor helicopter with loss of control effectiveness via simple adaptive control and quantum logic. Some good control performances of the helicopter can be achieved by applying quadratic optimal control with scheduled stability degree when the system is in normal operation. A parallel feedforward compensator is introduced to fulfill the condition of positive realness, and thus, the simple adaptive controller can be utilized for the helicopter. Quantum logic is also applied to the quadrotor control system, which achieves the quantization of the disturbances patterns. A mathematical model of the quadrotor helicopter for application is obtained from its dynamic equations with pitch, roll, and yaw axes, which includes the parameter perturbation and outer disturbances. Several simulation and experimental results for the faulty helicopter validate the robustness and reconfiguration control capability of the proposed scheme.

In this paper, an improved nonlinear model for a 3-DOF helicopter and its self-repairing control scheme are investigated via quantum information technique. Firstly, adopting the mechanism analysis, a modified dynamic model is developed, in which the couplings among axes are considered. Such a modeling scheme is useful for applications when the accuracy of original model can not be satisfied. Then, a reconfigurable control scheme is designed for the twin rotor helicopter with multiple faults and parametric uncertainties, which combines active disturbance rejection control method with model reference adaptive control method. In addition, quantum information technique is used to increase the accuracy of self-repairing control of helicopter. Finally, simulation verification is presented in both aspects of modeling and control. The effectiveness and feasibility of the proposed scheme are verified by comparative simulations.

Based on the nonlinear equations of a quadrotor, position tracking with unknown parameters and fault-tolerant control scheme is proposed in this article. First, a multi-loop structure is designed with multiple time-scale analysis to make the system realizable. Then, to achieve the goal of accurate tracking, a sliding mode fault observer is added into each loop to accommodate the effects of all the uncertainties. This controller shows great applicability because of the simple structure. The only information the controller needs to know is the limits of uncertainties. In addition, since the above controller cannot guarantee robustness when the system model is unknown, an online adaptive estimation method is proposed to learn the parameter information. Stability of the overall closed-loop system is analyzed with the Lyapunov stability theory, and output tracks the expected trajectory. The simulation is presented with several situations (including adaptive estimation result test/robust test under parameter uncertainties and high-frequency noise/fault-tolerant ability under actuator faults) to verify the effectiveness and feasibility of the proposed scheme.

In this paper, a new direct self-repairing control scheme is developed for a helicopter flight control system with unknown actuator faults and external disturbance. The design of multi-model-based adaptive control is used to accommodate the faulty system under different fault conditions. By appropriate switching based on quantum information technique, the system can be converted to the best model and the corresponding controller. Asymptotic model following performance and system stability is guaranteed. A disturbance observer is introduced to observe the disturbance of the system, which can produce corresponding control signals according to the disturbance. The results including a numerical simulation and a semi-physical verification demonstrate the effectiveness of the proposed self-repairing control approach for the helicopter flight control system.

A multiple model–based fault detection and diagnosis approach for a helicopter with actuator faults and disturbances is developed in this article. Particularly, the actuator is locked in-place and does not respond to subsequent commands. A multiple model scheme is proposed to detect and isolate the faults. In the multiple model scheme, a series of parallel observers are constructed, each of which is based on a model that describes the system in the presence of a particular actuator fault. In addition, quantum information technique is used to choose which model matches the current system. Furthermore, to estimate the locked position, a robust fast adaptive fault estimation algorithm based on linear matrix inequality technique is proposed by considering the disturbances. Finally, the simulation results show the efficiency of this scheme.

This study considers the attitude control problems of a quadrotor helicopter with actuator failures and external disturbance and thus proposes a self-repairing control scheme via adaptive control and quantum logic. An improved model reference adaptive compensation controller is designed to compensate for the failures and disturbance, as well as to guarantee that the attitude angles of the quadrotor helicopter track the state output of a given reference system in which the upper bounds of disturbance and the unparameterized stuck faults are unknown. The asymptotic state tracking properties of the designed adaptive system are proven using Lyapunov stability theory. In addition, quantum logic is introduced to increase the control accuracy of this method. Finally, a numerical simulation example is presented to demonstrate the validity of the proposed control scheme.

In this paper, the market demand forecasting of Sci-tech Service is investigated via an improved GMDH algorithm. The total revenue of Sci-tech Service Industry is specified as the index of market demand based on the assumption that the former is positively correlated with the latter. In order to reflect the research object veritably, fifteen influence factors are selected as the main parameters of such sci-tech service industry at first. Then, an improved GMDH algorithm is developed by adding initial variables into each layer, which is helpful to construct the multi-variable prediction model. In addition, BP neural network is adopted to predict the influence factors involved in the multi-variable model. Finally, simulation results are presented to verify the effectiveness of the proposed method.

An adaptive failure compensation control scheme is developed based on linear quadratic (LQ) control for discrete-time possibly nonminimum phase systems with unknown actuator failures with characterizations that some unknown system inputs are stuck at some unknown fixed or varying values at unknown time instants. The failure compensation control problem is formulated as a new LQ control problem. Based on some results on new controller structures and design conditions developed in [9], a stable adaptive law is proposed for the estimation of uncertain parameters from both the plant and actuator-failures. The adaptive failure compensation controller is implemented with adaptive parameter estimates, for achieving closed-loop stability and output regulation. Simulation results are presented to verify the desired adaptive control performance in the presence of uncertain actuator failures.

In this paper, an adaptive back-stepping control scheme was proposed for a helicopter with faults. The controller was made up by two parts: the equal controller and the back-stepping sliding mode controller. Firstly, the fault observer was brought in to observe the trend of the collective angle of blade resulted by the main faults, which can produce control signals according to the fault signals; And then in order to compensate the interference and the model dynamics errors, the adaptive back-stepping sliding mode controller was designed, the control laws were also given. Finally, the simulation results illustrated the effectiveness and feasibility of the scheme in the paper.

Non-small cell lung cancer (NSCLC) is a highly lethal malignancy that often becomes resistant to chemotherapy. The effect of silencing the X-linked inhibitor of apoptosis gene (XIAP) on resistance to cisplatin, paclitaxel and gemcitabine was studied in the NSCLC cell lines A549 and H460. Transfection of these cells with small interfering RNA (siRNA) for XIAP blocked overexpression of the gene, suppressed cell proliferation, increased apoptosis and increased the cells' sensitivity to cisplatin and paclitaxel by preventing the binding of XIAP to caspase-3 and increasing the activity of this enzyme. There was no significant difference in resistance to gemcitabine between XIAP-silenced cells and non-transfected cells. Changes in chemoresistance were independent of the activity of caspase-9. Silencing XIAP with siRNA can decrease chemoresistance in NSCLC and may have a potential role in the treatment of this disease.

In this paper, the problem of self-repairing control for unmanned aerial vehicles (UAVs) is analyzed via quantitative feedback theory and quantum control techniques. For the complex faults of unmanned aerial vehicles, a direct self-repairing control law based on quantitative feedback theory is proposed using quantum control techniques, which can guarantee the UAVs stable and solve the problem of UAVs robust control based on the uncertain parameters. Finally. Simulation results are given to illustrate the effectiveness of the self-repairing control developed in our study.

This paper proposes a robust adaptive strategy for longitudinal dynamics of generic hypersonic flight vehicles with uncertainties and faults. Flight vehicles are generally subjected to disturbances and multiple faults, which should be compensated for to preclude performance degradation. To solve this problem, considering fast abrupt faults such as actuator stuck faults, an adaptive fault observer is added into the nominal dynamic inversion controller to accommodate the effects of faults with discrete function patterns. In addition, since the above observer is designed only for fast abrupt faults, an online support vector machine compensator is proposed to learn the state error caused by other faults. As the error contains both dynamic uncertainties and slow variation faults, additional controllers are not required to get rid of the unwanted faults. Stability of the overall closed-loop system is analyzed with the Lyapunov stability theory, and output tracks the expected trajectory. The simulation i...

A novel self-repairing control scheme is proposed for a helicopter with unknown disturbance. Firstly, a disturbance observer is introduced to observe the disturbance of the system, which can produce corresponding control signals according to the disturbance signals. Secondly, an integral sliding mode controller is designed to compensate the unobserved disturbance and uncertainties. All of the closed-loop poles can be arbitrarily placed and the output errors converge to zero effectively through the controller. Besides, a robust closed-loop system against disturbance and parameter uncertainties is achieved. In addition, quantum information technique is used to increase the self-repairing control accuracy of helicopter. Finally, simulation results demonstrate the effectiveness and feasibility of the proposed self-repairing control scheme.

In this paper, are liable tracking control method based on the regional poles placement is utilized to solve the attitude tracking problem for the 3 Degree of Freedom(3-DOF) hovering system of Quadrotor with multi-actuator faults. For the uncertain linear system, a more practical and general model of actuator faults is presented. And a sufficient condition on reliable tracking is proposed. The state feedback reliable controller is solved interms of Linear Matrix Inequality(LMI). Finally, the simulation is examined on the Quanser 3-DOF hovering system to verify the feasibility and validity of the method.

This study gives the mathematic model of a quadrotor unmanned aerial vehicle (UAV) and then proposes a robust nonlinear controller which combines the sliding-mode control technique and the backstepping control technique. To achieve Cartesian position trajectory tracking capability, the construction of the controller can be divided into two stages: a regular SMC controller for attitude subsystem (inner loop) is first developed to guarantee fast convergence rapidity of Euler angles and the backstepping technique is applied to the position loop until desired attitudes are obtained and then the ultimate control laws. The stability of the closed-loop system is guaranteed by stabilizing each of the subsystems step by step and the robustness of the controller against model uncertainty and external disturbances is investigated. In addition, an adaptive observer-based fault estimation scheme is also considered for taking off mode. Simulations are conducted to demonstrate the effectiveness of the designed robust nonlinear controller and the fault estimation scheme.

In this paper, the integrated application on self-adapting control of the uninhabited combat aerial vehicles is investigated. According to the characteristics of the flight control systems on various stages, a series of compatible methods about MRAC are adopted to satisfy the flight performance of the unmanned fighter aircraft. Firstly, controller of actuator is constructed according to MIT law. Then the design of MRAC based on Lyapunovpsilas Second Method is applied to lateral flight control. Besides, the method based on Popov super-stability of longitudinal-flight-control is proposed. The simulation results show that the proposed scheme leads to better performance on stability and dynamic response of flight control systems.