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We investigated if poly‐lactic acid (PLA) nanopillar array can trigger the differentiation of human epicardial (ADSCs) (heADSCs) into cardiomyocyte‐like cells and explored the effects of these cardiomyocyte‐like cells on myocardial infarction (MI) in vivo. PLA nanopillar array (200 nm diameter) and plain PLA film (PLA planar) induced heADSCs were marked with carboxyfluorescein. After 7 days, the expressions of myocardiocyte‐specific genes were significantly enhanced in cells seeded on PLA nanopillar array compared with that on PLA planar, especially CACNA1C, KCNH2, and MYL2 genes (p < 0.05). However, the expressions of cardiac troponin T (cTNT), KCNQ1, and KCNA5 were lower than those in PLA planar‐induced heADSCs (p < 0.05), whereas GATA4 tended to increase with time. The cells with positively stained α‐actinin and cTNT were elevated in heADSCs induced by PLA nanopillar array compared with those induced by PLA planar only (p < 0.05). In vivo experiments showed that cardiac function was improved after injecting PLA‐nanopillar array‐induced heADSCs into the ischemic heart (p < 0.05, compared with PLA planar + MI group). Furthermore, tyrosine hydroxylase density was significantly lower (p < 0.05). PLA nanopillar array directly drives the differentiation of heADSCs into cardiomyocyte‐like cells, and the induced heADSCs exhibit a protective effect on ischemic myocardium by improving cardiac function in MI rats. [ABSTRACT FROM AUTHOR]

• Dual optical signals of gold nanoparticles, absorption and scattering, caused by the changes in dispersion state are used for analysis. • A dual-channel sensing platform based on fluorescence and Tyndall effect is achieved for Pb2+ detection in preserved eggs. • The amplification of DNAzyme pushes down the detection limit of Pb2+ in both modes to pM level. A dual-mode sensing platform for Pb2+ was constructed based on the dual optical channels of Au NPs system with the amplification of DNAzyme, and it was successfully applied for Pb2+ determination in preserved egg with satisfactory results. The presence of Pb2+ activated the DNAzyme and induced the dispersion change of Au NPs in high salt concentration. The sequent absorption change of Au NPs was translated to the fluorescence change of carbon dots through FRET, and the scattering change was transferred to grey value of images involving the Tyndall effect. Thus, a sensing platform based on fluorescence and colorimetric dual-technique was achieved for Pb2+ detection, under the optimized conditions. With the assistance of DNAzyme, the linear range of fluorometric and colorimetric method were 2.0 × 10-14 ∼ 8.0 × 10-10 mol/L and 2.4 × 10-13 ∼ 9.5 × 10-9 mol/L, respectively. The dual-mode sensing platform demonstrated its promising application in the environmental monitoring and food safety field. [ABSTRACT FROM AUTHOR]

Based on a four‐phase 8/6 structure switched reluctance machine for electric vehicles, the influence of different magnetic pole distributions on iron loss and temperature field is studied here. Firstly, by fitting the core silicon sheet iron loss data of the prototype, a mathematical calculation model of switched reluctance iron loss is constructed. Then, in order to analyse the flux density waveform of the iron core, a 2D finite element model is proposed. Under different magnetic pole distributions, the magnetic flux densities of the iron core are compared and the iron loss is calculated as well. Finally, the simulation results are obtained by establishing the 2D finite element thermal model of the prototype and analysed. Then, the experimental test platform is built and experimental data are recorded and analysed. By comparing the experimental results, it is found that the temperature rise is well consistent with the temperature rise of the 2D finite element thermal model. [ABSTRACT FROM AUTHOR]

This paper analyzed the flux characteristics of a single-phase tubular switched reluctance linear motor (TSRLM) based on magnetic equivalent circuit (MEC) method. The single-phase TSRLM is divided into five different parts, which are the teeth of the stator, the yoke of the stator, air gap, the teeth of the mover, and the yoke of the mover. The reluctance of every part is expressed in analytical formulas at five special mover positions. The flux linkages at five special mover positions are calculated by magnet tube method and Gauss–Seidel iteration method which takes the saturation into consideration. A high-order Fourier series method is used to map the nonlinear relationship between flux linkage, current, and mover position with the flux linkage data calculated by the MEC method. The calculated flux linkage is consistent with 3-D finite-element method and experimental results. The dynamic and static performance of the simulation utilized with MEC method is consistent with those in experiments, which verifies the accuracy of the MEC method proposed in this paper. [ABSTRACT FROM AUTHOR]

The iron loss of doubled-sided linear switch reluctance motor (DLSRM) is analyzed and calculated in this paper. Because of the double salient structure of the switched reluctance motor and the nonlinearity of the magnetization curve of the ferromagnetic material, the flux density waveform is nonsinusoidal. So, it is difficult to calculate the iron loss of DLSRM. This paper mainly introduces the calculation method of dynamic magnetic density of the DLSRM, and basing on this, the simulation model of iron loss of DLSRM is built and compared the iron loss in different parts of the total as a percentage of the motor. Finally, an experimental platform based on DLSRM is built to measure the actual iron loss in the motor and verify the correctness of the calculation of iron loss. [ABSTRACT FROM AUTHOR]

In this study, the design optimisation of a switched reluctance machine (SRM) with the layered method has been studied. Firstly, a multi‐physical analytical model for the SRM is established. The proposed model consists of an electromagnetic model, an electrical model, a loss model, and a thermal model. Then a layered optimisation design method suitable for the SRM is proposed in combination with the multi‐physical field simulation model. Taguchi method is used to analyse the influence degree of the main geometric dimensions on the dynamic performance, and the parameters are divided into high‐sensitivity parameters (HSPs) and low‐sensitivity parameters. The non‐dominated sorting genetic algorithm‐II algorithm is used to optimise the HSP by the proposed model. The iron loss, average torque, average torque per unit mass, torque ripple and efficiency are taken as the objective functions. Finally, the prototype is manufactured and a testing platform is built. The flux linkage of several special positions of the machine is verified experimentally, and the accuracy of the electromagnetic model in the multi‐physical field model is verified. The temperature experiments are carried out on the machine, and the accuracy of the equivalent heat circuit model in the multi‐physical field model is verified. [ABSTRACT FROM AUTHOR]

This paper analyzes the flux characteristics and normal force of the double-sided switched reluctance linear machine (SRLM) under the asymmetric air gap. The magnetic equivalent circuit (MEC) of the machine and the details of the flux paths configuration at six distinct mover positions under the asymmetric air gap are included. Then, six special mover position magnetization curves are calculated by solving the MEC with the method of Gauss–Seidel. The magnetic flux-linkage model and thrust model based on six distinct mover positions are established by analytical polynomial. Three-dimensional (3-D) finite-element method (FEM) simulation and the experimental study with the prototype hardware are carried out to validate the accuracy of the MEC model calculated for the flux linkage and normal force. The six distinct mover positions flux linkage and normal force calculated by the MEC are consistent with the 3-D FEM calculated data and experimental data. It indicates that the proposed method to calculate the flux linkage and the normal force is feasible and effective. The dynamic analysis is also conducted. The simulated phase current waveforms are also consistent with the experimental results. It indicates that the presented method can be used to simulate the phase current under the asymmetry air gap effectively. The normal force under different asymmetry rates is analyzed, which provides the theoretical basis for reducing the unbalanced force of the double-sided SRLM. [ABSTRACT FROM AUTHOR]

This study sets forth an equivalent electric circuit (EEC) model including core losses and phase interactions to obtain a more accurate steady and dynamic performance of the high speed switched reluctance motor (SRM) during the design, analysis, and control of the SRM drive system. The magnetic equivalent circuit (MEC) method is used to calculate the flux linkage and torque quickly and relative accurately. Based on the principle of transformation between the MEC and EEC, the EEC model is derived from the MEC model. To enhance the model precision, the dynamic core losses and phase interactions are analysed and added to the EEC model. The relationship between the phase current and virtual current corresponding to different parts is deduced. Then the simulation model of the whole SRM driver systems is established in MATLAB/Simulink to obtain the phase current and virtual current corresponding to a different portion. The experimental and simulated results of the static MEC model and the whole SRM drive system including the EEC model provide the conclusive evidence for validating their practicability. [ABSTRACT FROM AUTHOR]

This article investigates the design methods and performance optimization of segmented-double-stator switched reluctance machine (SDS-SRM). First, two segmented U-shaped single-stator SRMs are introduced, including inner-rotor and outer-rotor constructions. In order to enhance the torque and power density, these two kinds of single-stator SRMs are combined together to constitute an SDS-SRM. Then, the relationships of torque ripple coefficient with the mechanical offset angles of the inner and outer rotor teeth are investigated to obtain the optimal rotor structure, and the corresponding conduction phase sequences for double-stator excitation mode are also analyzed. Furthermore, the flux distributions of the inner and outer stators with different coil magnetic polarities configurations are researched, and it reveals that the phase windings both on inner and outer stators with NSSNNSSN polarities have better magnetic field decoupling characteristics. To evaluate the final topology of the proposed SDS-SRM, the static magnetic characteristics and dynamic performances are presented. Finally, the SDS-SRM prototype is manufactured and tested to validate the theory and simulation analyses. [ABSTRACT FROM AUTHOR]

This paper mainly takes a 6/4 switched reluctance motor (SRM) as an example to analyze the temperature of the motor. In order to establish the equivalent thermal circuit model (ETCM) conveniently, the mechanical structure of the motor is simplified to a certain extent, and the characteristic nodes are divided. Then the heat transfer process in the rotor region, the stator region and the whole motor during the operation of the motor is analyzed, and the ETCM of those regions are established respectively. This method of establishing ETCM is also applicable to superconducting motors. Based on the basic principles of heat transfer, the calculation method of thermal resistance in each ETCM is given in this paper. Then, the three-dimensional (3-D) finite element (FE) temperature field model of the motor is built and compared with the ETCM. Finally, the accuracy of the ETCM is verified by experiments. [ABSTRACT FROM AUTHOR]

A dual-mode pH sensor based on nitrogen-doped carbon dots (N-CDs) with the source of o-phenylenediamine and tryptophan has been constructed. Under the stimulation of pH, the N-CDs exhibited prominent both color and fluorescence changes, leading to the rarely discovered colorimetric and fluorescent dual-readouts for the evaluation of pH. The mathematic relationship was established between pH and fluorescence intensity of N-CDs, and between pH and the UV–Vis absorbance ratio at 630 nm and 488 nm of N-CDs, respectively, over a quite broad pH range of 2.2 to 12.0. Multiple techniques are used to explore the dual-mode pH-responsive mechanism, and the preliminary explanation is put forward. The experimental results show that the N-CDs have visualized pH sensing applicability for actual samples, including various water samples and HeLa cell. Furthermore, the N-CD ink is developed for successful information encryption and anti-counterfeiting. This work might provide valuable insights into the sensing mechanism of CDs, and the application potential of CDs in broader fields. [ABSTRACT FROM AUTHOR]

This paper calculates the flux characteristic of a single-phase tubular switched reluctance linear launcher (TSRLL) with 3-D magnetic equivalent circuit (MEC) method. First, the 3-D finite element (FE) model of the single-phase TSRLL is established in FLUX, which is the foundation of the 3-D MEC model. The single-phase TSRLL is divided into different parts, including the teeth of the stator, the yoke of the stator, air gap, the teeth of the mover, and the yoke of the mover. The flux linkage at different mover positions and different currents is calculated with the proposed 3-D MEC model. Compared with the 3-D finite-element analysis (FEA) results, 3-D MEC model can obtain the flux characteristics of the single-phase TSRLL in a shorter time. The result of the 3-D MEC of the single-phase TSRLL is consistent with the 3-D FEM results and the experimental results, which validates the correctness of the proposed 3-D MEC model. [ABSTRACT FROM AUTHOR]

This paper gives a way to analyze the flux characteristic of a single-phase tubular permanent magnet linear motor (TPMLM) based on the 3-D magnetic equivalent circuit (MEC) method. By studying the flux tubes of this single-phase TPMLM with the finite-element analysis software—FLUX, a 3-D MEC model of this motor can be constructed, and the flux linkage of the single-phase TPMLM can also be calculated. The static and dynamic performances of the single-phase TPMLM calculated with the 3-D MEC model are compared with the 3-D finite-element model and experimental results, which verify the correctness of the proposed 3-D MEC model. [ABSTRACT FROM AUTHOR]

Tubular switched reluctance linear motor (TSRLM) has lower loss and higher thrust density than flat-type switched reluctance linear motor. Two kinds of single-phase TSRLMs with different surrounding magnetic flux paths are introduced in this paper. The structure of transverse flux TSRLM (TF-TSRLM) is compared with the structure of the longitudinal flux TSRLM (LF-TSRLM). The structure selection of TF-TSRLM with two poles, four poles, six poles, and eight poles is made for enhancing average electromagnetic thrust. The comparisons between LF-TSRLM and TF-TSRLM are made in the same stator outer diameter, the same mover laminated thickness, and the same excited current on static electromagnetic thrust, magnetization curves, average thrust per unit volume, and average thrust per unit mass. They show that the TF-TSRLM with the six-pole structure is considered as a relatively more reasonable structure for enhancing the space effective utilization rate and increasing the electromagnetic thrust. [ABSTRACT FROM AUTHOR]

A fast method to calculate the iron loss of switched reluctance motor (SRM) is proposed. The key of the method is that the flux density waveforms in different parts of the motor can be obtained quickly. First, the static flux density data varying with phase current and rotor position in various parts of SRM are obtained by finite element method (FEM). Then, the static flux density data are stored in 2D look‐up tables in Matlab/Simulink to get the flux density waveforms by look‐up table method, and the obtained flux density waveforms are verified by FEM results. Since the flux waveforms are non‐sinusoidal and non‐linear, an accurate and fast model for the iron loss prediction is presented, and different modified factors are applied to calculate the hysteresis loss according to the classification of flux density waveforms. Based on that, the calculation model is established in Matlab/Simulink, and iron losses of a three‐phase 6/4 structure SRM under different turn‐on and turn‐off angles and load conditions are calculated and analysed. Finally, measured results are presented to verify the precision of the calculation model. [ABSTRACT FROM AUTHOR]

Presents corrections to financial data posted for this article. [ABSTRACT FROM AUTHOR]

Abstract Recent studies have demonstrated that dysregulation of mircoRNAs (miRNAs) greatly affected biological processes of human cancers, including colorectal cancer. As a member of miRNAs family, miR-873-5p has been proved to be a tumor suppressor in some human cancers. Here, we aim to investigate the effects of miR-873-5p on the migration, invasion and epithelial-mesenchymal transition (EMT) of colorectal cancer cells. The low expression of miR-873-5p in colorectal cancer cells was identified by conducting qRT-PCR analysis. Gain of function assays were designed and conducted to demonstrate the specific function of miR-873-5p overexpression in colorectal cancer progression. Transwell assay and western blot assay were conducted and revealed that miR-873-5p inhibited cell migration, invasion and EMT formation. To find the downstream molecular mechanism of miR-873-5p, mechanism assays were designed and performed to find the downstream target of miR-873-5p. ZEB1 (Zinc finger E-box-binding homeobox 1) was certified to be the target of miR-873-5p through bioinformatics analysis, luciferase activity assay and pull-down assay. Finally, rescue assays were carried out to demonstrate the effects of miR-873-5p-ZEB1 axis on the migration, invasion and EMT process of colorectal cancer cells. In conclusion, we confirmed that miR-873-5p suppressed cell migration, invasion and EMT in colorectal cancer via targeting ZEB1. [ABSTRACT FROM AUTHOR]