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EMS maglev train uses the active control system to maintain the levitation stability, time delay is widespread in control system. However, the existing maglev dynamics studies rarely consider the effect of time delay, so these analysis results cannot directly guide the engineering design. This paper starts from a theoretical analysis of the levitation stability of a single electromagnet levitation system to obtain the theoretical critical value for the time delay. Then the model is gradually extended to a complete vehicle model and a vehicle-girder coupling dynamics model to find the time delay engineering critical values for the complex coupling system. In order to seek ways to reduce the influence of time delay on the dynamic responses, this paper analyzes the influence regularities of the running speed and control parameters on the dynamic response under the effect of time delay. The result shows that the theoretical critical value of the time delay is equal to the ratio of the differential coefficient and proportional coefficient of the PID controller. For a complex maglev system, the engineering critical value is less than the theoretical critical value. Higher running speeds lead to time delay having a more obvious effect on the maglev system’s dynamic responses. Selecting the smaller proportional coefficient and appropriate differential coefficient for the levitation control system can expand the stability region and reduce the influence of time delay on the maglev system. This analysis is helpful and meaningful to the understanding of the EMS vehicle system stability, and helpful to explore the reason of violent coupled vibration in actual engineering.

Background and Objective: Metastasis is the leading cause of death in patients with advanced non-small cell lung cancer (NSCLC), and epithelial-mesenchymal transition (EMT) is a crucial event in the metastasis of NSCLC. Our previous works demonstrated that NgBR promoted EMT in NSCLC. However, the molecular mechanism was unclear. Methods: TGF-β1 was used to induce EMT process of NSCLC cells. The biological functions of NgBR in promoting TGF-β1-induced NSCLC metastasis were studied by gain- and loss-of-function assays both in vitro and in vivo. The underlying mechanisms were studied using molecular biology assays. Results: We found that knockdown of NgBR inhibited TGF-β1-induced cell migration and invasion in NSCLC cells. In contrast, NgBR overexpression promoted TGF-β1-induced EMT of A549 cells. Mechanically, we found that knockdown of NgBR facilitated ubiquitination and degradation of TβRI, leading to downregulation of TβRI expression in NSCLC cells. Moreover, we confirmed a positive correlation between NgBR and TβRI in NSCLC tissues. Conclusions: Our findings provide a novel role of NgBR in modulating TGF-β1-induced EMT and propose NgBR as a new therapeutic target for treating NSCLC patients.

The aim of the present study was to report a clinical survey of hereditary multiple exostoses (HME) in a large Chinese pedigree, and the identification of a novel deletion mutation of exostosin glycosyltransferase 2 (

With increased electric power replacing other secondary power in more electric aircraft (MEA), as a result, aircraft electrical power system (EPS) will face enormous challenges related to design optimization and system stability. This paper focuses on the modeling and impedance characteristics analysis of the three-stage DC generator in the 270V DC EPS for MEA, which is a critical factor in the system stability. The detailed model of the three-stage generator is derived based on the two-port network model. Then the characteristics of output impedance are analyzed and the influence of some factors including the DC-bus capacitor and control bandwidth on the output impedance is discussed. Some simulations are performed to verify the correctness of the theory.

Variable frequency AC power system is an important development direction for the main power supply system of civil aircraft. In this paper, a method of using Saber simulation software to build More-Electric Aircraft electrical system is proposed. This paper introduces the electrical system of the More-Electric Aircraft first, and then uses the Saber simulation software to build and analyze an accurate simulation model of the power supply system and two typical loads. The stability of the variable frequency AC power system is analyzed by equipping different electrical loads under different working conditions. The simulation results show that the 230 V variable frequency AC power system can quickly recover to a stable state after sudden loading, power halving and sudden unloading with lighting loads and 3 kW constant power loads, which lays the foundation for further research on the power stability of variable frequency AC power systems.

Autotransformer rectifier unit (ATRU) is one of the most important high power AC-DC electrical equipment. The electrical performance of ATRU is severely degraded under the condition of the diodes open-circuit, which causes the subsequent loads to work abnormally. This paper presents a diode open-circuit fault (OCF) diagnosis method based on the difference of DC output voltage between normal and fault conditions. Due to the absence of the specific output path for voltage phasor caused by the OCFs, the waveforms for DC output voltage will appear the sags, which are considered as features of OCFs and extracted by calculating the Hausdorff distance (HD) between the output voltage sampling and the template sequence. Then, fault diodes can be further located according to the difference of sags positions and the phase of the input voltage. The proposed method is simple and easy to implement since only the output voltage and single-phase input voltage need to be sampled. Simulation and experimental results confirm that the proposed method can detect and locate the diodes of OCF accurately. Moreover, the proposed method is beneficial to the isolation of the faulty ATRU and greatly shortens its repair time.

For on/off-grid DC microgrid, this paper proposes an improved droop control strategy combined with DC bus signaling to split transient and average load power between supercapacitor (SC), battery, and grid. SC converter with virtual impedance droop is responsible for supplying transient load power, whereas battery converter and grid rectifier, both with virtual resistor droop, are responsible for additional average load power in off-grid and on-grid modes, respectively. DC bus signaling is implemented for the smooth transition of DC microgrid from off-grid to on-grid state. The working methods for the proposed control strategy and the design of the system are explained, and theoretical analyses are verified by simulations.

This paper proposes an extended droop control strategy for dynamic transient power-sharing between supercapacitor (SC) and AC grid to manage the power demand in the DC microgrid. The proposed control strategy utilizes a virtual impedance droop structure with the SC converter and a virtual resistor droop structure with the grid rectifier, which are responsible for splitting the load power into transient and average load power, respectively. Load transient caused by a sudden change in the load is buffered by supercapacitor and additional average load power demand is supplied by the grid. The working methods of the proposed control strategy and the design of the system are explained, and theoretical analyses are verified by simulations.

Nogo-B receptor (NgBR) is a specific receptor of Nogo-B that regulates vascular remodeling and angiogenesis. Previously, we found that NgBR promotes the membrane translocation and activation of Ras in breast cancer cells and enhances the chemoresistance of hepatocellular carcinoma cells to 5-fluorouracil. However, the role of NgBR in lung cancer has not yet been elucidated. In the present study, we found that NgBR knockdown inhibited epithelial–mesenchymal transition (EMT) in non-small cell lung cancer (NSCLC) cells in vitro and metastasis of NSCLC cells in vivo. In contrast, NgBR overexpression promoted EMT in and lung metastasis of NSCLC cells. At the molecular level, NgBR modulated the expression of EMT-related proteins and enhanced the protein expression of Snail1, a crucial transcription factor that represses epithelial cell protein marker E-cadherin. Moreover, we found that NgBR overexpression promoted the membrane localization of Ras and activation of downstream MEK/ERK signaling pathway and that NgBR knockdown by using a specific shRNA inversely affected the expression of EMT-related proteins in NSCLC cells. Thus, our results provide novel insights on the regulatory role of NgBR in the metastasis of NSCLC that should be investigated further for developing a therapeutic strategy for treating patients with NSCLC.

In the millimeter wave train-ground communication system of high-speed maglev train, train-mounted antennas are required to have the characteristics of miniaturization, wide band, circular polarization, and fan-beam radiation. A side-feed rectangular waveguide helical array antenna is designed to meet these requirements in this paper. Short axial-mode helical antenna which has compact structure and circularly polarized radiation characteristics is used as the unit antenna. To realize fan-beam radiation characteristics, this array is composed of 2×15 unit antennas. All elements are fed by a rectangular waveguide which is divided into two rectangular waveguides from the side direction of the antenna. By properly designing the length of the coupling probe in the feed system, an equal excitation amplitude distribution can be realized for all unit antennas. The radiation phase of the unit antenna can be adjusted by rotating the helix arounding its axis to realize in-phase radiation of all elements. An array antenna with a center frequency of 38.0 GHz was designed through simulation. Simulation results show that the antenna has a gain of 22.1dB, an axial ratio of 2.09dB, an elevation plane beam width of 4.4°, an azimuth plane beam width of 30.1° at 38.0GHz. In the band of 37.0-39.0GHz, the reflection coefficient of this antenna is less than -15dB, the antenna gain is greater than 21.5dB and the axial ratio is less than 2.0dB which meet the design requirements of train-mounted antenna in the millimeter wave train-ground communication system.

High-speed maglev rail line adopts an elevated structure, which makes the train roof a local high point. Due to an absence of lightning protector along maglev rail line, train roof can easily attract lightning strikes in thunderbolt weather because of its height. As the maglev train is suspended without any mechanical contact with rail track when operating under high-speed, strong currents generated by lightning strike is unable to be conducted to the ground. Therefore, the lightning strike currents could produce a great over-voltage fluctuation on car body and further threatens operation safety of high- speed maglev train. In this paper, regarding the structure of high-speed maglev rail line, the related standards of lightning protection are studied. Considering the characteristic of ground equipment and the characteristic of maglev train, the grounding system structure and lighting current discharge path of high-speed maglev are analyzed. Combined with lightning current characteristic and impedance characteristic of car body, a lightning protection design method for grounding system of high-speed maglev is put forward.

Our previous study demonstrated that aldolase A (ALDOA) is overexpressed in clinical human lung squamous cell carcinoma and that ALDOA promotes epithelial-mesenchymal transition and tumorigenesis. The present study aimed to explore the function of ALDOA in the modulation of non-small cell lung cancer (NSCLC) proliferation and cell cycle progression and the potential mechanism.ALDOA was knocked down by short hairpin RNA in H520 and H1299 cells. ALDOA was overexpressed with vectors carrying the full-length ALDOA sequence in H1299 and H157 cells. The proliferation capacities were assessed with immunohistochemical staining, Cell Counting Kit-8 and colony formation assays. The cell cycle distribution was examined by flow cytometry, and molecular alterations were determined by western blotting. Cell synchronization was induced with nocodazole. The stability of cyclin D1 mRNA was tested. The pyruvate kinase M2 and ALDOA protein distributions were examined. Aerobic glycolysis was evaluated with Cell Titer-Glo assay, glucose colorimetric assay and lactate colorimetric assay.ALDOA knockdown inhibited the proliferation and GALDOA contributed to activation of the EGFR/MAPK pathway, thus promoting cyclin D1 expression and enhancing proliferation and G

At present, the SiC devices have been widely concerned with the excellent characteristics of low switching losses, which can significantly improve the frequency of power electronic converters, and also have broad application prospects in the field of rail transportation. In this paper, through the establishment of 1500V powered subway auxiliary inverter loss model, the author estimated loss and efficiency of high frequency DC/DC and three-phase inverter under different switching frequency in SiC MOSFET and Si IGBT system, determined the switching frequency for reference in high frequency DC/DC and three-phase inverter, and the analysis shows that the application of SiC MOSFET can reduce the loss of the system, improve the efficiency of the system. Then the author built a simulation model of auxiliary converter model, verified the reliability of SiC filter, setted up a 40kW high frequency DC/DC module with the SiC device selection in this paper, and the module has the efficiency of 97.85% under rated power. The above work provides theoretical support and experimental support for the hardware construction of SiC auxiliary converter.

Robust analysis is important for designing and analyzing algorithms for global optimization. In this paper, we introduce a new concept, robust constant, to quantitatively characterize the robustness of measurable sets and functions. The new concept is consistent to the theoretical robustness presented in literatures. This paper shows that, from the respects of convergence theory and numerical computational cost, robust constant is valuable significantly for analyzing random global search methods for unconstrained global optimization.

As an electric multiple units (EMU) train closes its main circuit breaker, an overvoltage may occur in the traction windings and the magnetizing inrush current may emerge in the primary winding of the traction transformer. This electromagnetic transients can disturb the electric equipment onboard, as well as emit high-frequency electromagnetic interference, which can hazard the normal operation of EMU. Taking the CRH2 EMU as an example, the mechanism of electromagnetic transients when closing the main circuit breaker is investigated theoretically based on the simple equivalent circuit. Then, using EMTDC/PSCAD, a simulation model of the high-voltage electrical system is established. The simulated results, which analyze factors that influence the overvoltage in traction windings and the magnetizing inrush current in primary winding, are given. To validate the simulation model, the simulated results are compared with the measured data. In the end, a solution is put forward to improve CRH2 transient performance.

In this paper, we propose a new method, namely the level-value estimation method, for finding global minimizer of continuous optimization problem. For this purpose, we define the variance function and the mean deviation function, both depend on a level value of the objective function to be minimized. These functions have some good properties when Newton’s method is used to solve a variance equation resulting by setting the variance function to zero. We prove that the largest root of the variance equation equals the global minimal value of the corresponding optimization problem. We also propose an implementable algorithm of the level-value estimation method where importance sampling is used to calculate integrals of the variance function and the mean deviation function. The main idea of the cross-entropy method is used to update the parameters of sample distribution at each iteration. The implementable level-value estimation method has been verified to satisfy the convergent conditions of the inexact Newton method for solving a single variable nonlinear equation. Thus, convergence is guaranteed. The numerical results indicate that the proposed method is applicable and efficient in solving global optimization problems.

Alternating directions methods (ADMs) are very effective for solving convex optimization problems with separable structure. However, when these methods are applied to solve convex optimization problems with three separable operators, their convergence results have not been established as yet. In this paper, we consider a class of constrained matrix optimization problems. The problem is first reformulated into a convex optimization problem with three separable operators, then it is solved by a proposed partial parallel splitting method. The proposed method combines the parallel splitting (augmented Lagrangian) method (PSALM) and the alternating directions method (ADM), and it is referred to as PADALM in short. The main difference between PADALM and PSALM is that in PADALM, two operators are handled first by a parallel method, then the third operator and the former two are dealt with by an alternating method. Finally, the convergence result for PADALM is established and numerical results are provided to show the efficacy of PADALM and its superiority over PSALM.

Parallel iterative methods are powerful in solving large systems of linear equations (LEs). The existing parallel computing research results focus mainly on sparse systems or others with particular structure. Most are based on parallel implementation of the classical relaxation methods such as Gauss-Seidel, SOR, and AOR methods which can be efficiently carried out on multiprocessor system. In this paper, we propose a novel parallel splitting operator method in which we divide the coefficient matrix into two or three parts. Then we convert the original problem (LEs) into a monotone (linear) variational inequality problem (VI) with separable structure. Finally, an inexact parallel splitting augmented Lagrangian method is proposed to solve the variational inequality problem (VI). To avoid dealing with the matrix inverse operator, we introduce proper inexact terms in subproblems such that the complexity of each iteration of the proposed method is O(n^2). In addition, the proposed method does not require any special structure of system of LEs under consideration. Convergence of the proposed methods in dealing with two and three separable operators respectively, is proved. Numerical computations are provided to show the applicability and robustness of the proposed methods.

RIOK3 was initially characterized as a homolog of Aspergillus nidulans sudD and showed down-regulation at the invasive front of malignant melanomas, but the molecular mechanism remains elusive. Here, we report that overexpression of RIOK3 inhibits TNFalpha-induced NF-kappaB activation, but down-regulation of endogenous RIOK3 expression by siRNA potentiates it. A yeast two-hybrid experiment revealed that RIOK3 interacted with caspase-10, and further, a GST pull-down assay and endogenous coimmunoprecipitation validated the interaction. We subsequently showed that the interaction was mediated by the RIO domain of RIOK3 and each death effector domain of caspase-10. Interestingly, our data demonstrated that RIOK3 suppressed caspase-10-mediated NF-kappaB activation by competing RIP1 and NIK to bind to caspase-10. Importantly, the kinase activity of RIOK3 was confirmed to be relevant to NF-kappaB signaling. Taken together, our findings strongly suggest that RIOK3 negatively regulates NF-kappaB signaling pathway activated by TNFalpha dependent on its kinase activity and NF-kappaB signaling pathway activated by caspase-10 independent of its kinase activity.

In this paper, the dual $L_p$ John ellipsoids, which include the classical Löwner ellipsoid and the Legendre ellipsoid, are studied. The dual $L_p$ versions of John's inclusion and Ball's volume-ratio inequality are shown. This insight allows for a unified view of some basic results in convex geometry and reveals further the amazing duality between Brunn–Minkowski theory and dual Brunn–Minkowski theory.

We establish in this paper some inequalities for medians and volumes of two simplices whose form is analogous to the Neuberg-Pedoe inequality.

Robust analysis is important for designing and analyzing algorithm for global optimization. In this paper, we introduced a new concept, robust constant, to quantitatively characterize robustness of measurable sets and measurable functions. The new concept is consistent with the robustness proposed in literature. This paper also showed that robust constant had significant value in the analysis of some random search algorithms for solving global optimization problem.

Multi-processor system real-time scheduling algorithm for flight assignment problem was proposed. By constructing the flight queue model, the real-time scheduling algorithm was applied to a example and achieved satisfactory results. The time cost was less than 3 ms. The experiment results showed that the algorithm is faster than the genetic algorithm 2 orders of magnitude, faster than branch and bound almost an order of magnitude.

To screen the differential expression genes of KANLAITE in anti-tumor metastasis.mRNA was extracted and purified from the lung of the mouse with LA795 lung metastasis, hybridized respectively on 4 096-gene chip. cDNA microarray was scanned for the fluorescent signals and analyzing difference expression.Twenty-seven differential expressed genes were obtained. Among these genes, 25 were up-regulated and 2 were down-regulated. Twelve of them were Mus musculus cDNA clone. Six genes related with genesis, development and metastasis of tumor.cDNA microarray for analysis of gene expression patterns is a powerful method to identify differential expressed genes. In this study, 6 genes are thought to be associated genes of KANGLAITE in anti-tumor metastasis.

Due to the importance of Power/Ground network, lots of researches have been made on it. But they only focused on the minimal area of it. By discussion on the relation among Vdd, performance and power consumption, this paper proposes an optimal algorithm using GA and SLP method where area, performance and power consumption can be simultaneously evaluated. As a result, the Power/Ground network is designed by adjusting the wire width to supply the proper Vdds. The convergence of the algorithm is proved. Experimental results and simulations also show that the proposed algorithm can produce a good Power/Ground network.