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Human trophoblast cells are crucial for healthy pregnancy. However, whether the defective homologous recombination (HR) repair of dsDNA break (DSB) in trophoblast cells may induce miscarriage is completely unknown. Moreover, the abundance of BRCA1 (a crucial protein for HR repair), its recruitment to DSB foci, and its epigenetic regulatory mechanisms, are also fully unexplored. In this work, it is identified that a novel lnc‐HZ10, which is highly experssed in villous tissues of recurrent miscarriage (RM) vs their healthy control group, suppresses HR repair of DSB in trophoblast cell. Lnc‐HZ10 and AhR (aryl hydrocarbon receptor) form a positive feedback loop. AhR acts as a transcription factor to promote lnc‐HZ10 transcription. Meanwhile, lnc‐HZ10 also increases AhR levels by suppressing its CUL4B‐mediated ubiquitination degradation. Subsequently, AhR suppresses BRCA1 transcription; and lnc‐HZ10 (mainly 1‐447 nt) interacts with γ‐H2AX; and thus, impairs its interactions with BRCA1. BPDE exposure may trigger this loop to suppress HR repair in trophoblast cells, possibly inducing miscarriage. Knockdown of murine Ahr efficiently recovers HR repair in placental tissues and alleviates miscarriage in a mouse miscarriage model. Therefore, it is suggested that AhR/lnc‐HZ10/BRCA1 axis may be a promising target for alleviation of unexplained miscarriage. [ABSTRACT FROM AUTHOR]

A decoupling control strategy of three‐phase inverter, which can realize complete decoupling of the active and reactive current in the synchronous reference frame (SRF) is proposed here. There are two coupling factors of current loop in SRF, one is time delay caused by digital control, and the other is AC filter. Dynamic time delay compensation is applied to eliminate coupling caused by the first factor. The phase of the bridge leg voltage can be predicted. The difference between it and the phase of reference voltage which takes part in pulse width modulation (PWM) is the dynamic compensation angle, which can compensate the time delay. High‐order feedforward compensation is applied to eliminate coupling caused by the second factor. Complex vector model of the LCL filter is derived and the high‐order coupling coefficients can be offset by feedforward compensation. The coupling characteristics and compensation principles are analysed in detail. The system stability is discussed. Finally, the simulation and experimental results are given to verify the theoretical analysis. [ABSTRACT FROM AUTHOR]

A swirling flow tundish is developed to deeply clean the liquid steel through enhancing the coalescence of inclusions. The swirling flow is generated using the gravitational energy of liquid steel, without any external energy. Inclusions will gather to the center of the swirling flow by centripetal force, due to the density difference between inclusions and liquid steel. Thus, small inclusions can coalesce into larger ones, and then float to the top surface by their self‐buoyance. Physical experiments are carried out in a 1/2.5 scale five‐strand tundish, to investigate flow characteristics in the swirling flow tundish, compared with that in the tundish with a conventional turbulent inhibitor. Numerical modeling is developed to evaluate the swirling strength of liquid flow in swirling chambers in different sizes, which is related to the effect of inclusion coalescence. The results reveal that swirling chamber in diameter of 700 mm produces the highest swirling flow strength. The swirling system can not only improve the flow field, with a 21.75% reduction of dead volume, but also uniform flow characteristics at each strand. In addition, the swirling chamber inhibits the normal impact of the reversed flow on tundish surface, which is beneficial for remaining a stable slag layer. [ABSTRACT FROM AUTHOR]

Normal pregnancy is essential for human reproduction. However, BaP (benzo(a)pyrene) and its metabolite BPDE (benzo(a)pyrene‐7,8‐dihydrodiol‐9,10‐epoxide) could cause dysfunctions of human trophoblast cells and might further induce miscarriage. Yet, the underlying mechanisms remain largely unknown. Herein, we identified a novel upregulated lnc‐HZ04 and a novel downregulated miR‐hz04 in villous tissues of unexplained recurrent miscarriage (RM) relative to those in healthy control tissues and also in BPDE‐treated human trophoblast cells. Lnc‐HZ04 directly and specifically bound with miR‐hz04, diminished the reduction effects of miR‐hz04 on IP3R1 mRNA expression level and on IP3R1 mRNA stability, and then activated the Ca2+‐mediated IP3R1/p‐CaMKII/SGCB pathway, which further promoted trophoblast cell apoptosis. The miR‐hz04 target site on lnc‐HZ04 played crucial roles in these regulations. In normal trophoblast, relatively less lnc‐HZ04 and more miR‐hz04 suppressed this apoptosis pathway and gave normal pregnancy. After exposure to BPDE or in RM tissues, p53 was upregulated, which might promote p53‐mediated lnc‐HZ04 transcription. Relatively more lnc‐HZ04 and less miR‐hz04 activated this apoptosis pathway and might further induce miscarriage. BaP could also induce mice miscarriage by upregulating its corresponding murine apoptosis pathway. Therefore, BPDE‐induced apoptosis of human trophoblast cells was associated with the occurrence of miscarriage. This work discovered the regulation roles of lnc‐HZ04 and miR‐hz04 and provided scientific and clinical understanding of the occurrence of unexplained miscarriage. [ABSTRACT FROM AUTHOR]

A position sensor is usually required in the existing fault‐tolerant direct torque control (FT‐DTC) system for the multiphase permanent magnet synchronous motor (PMSM). Thus, the volume, weight, and cost of the system is increased, and the reliability is decreased. The conventional high‐performance position sensorless strategies for the multiphase motor under fault‐free condition cannot be directly applied to FT‐DTC system. To improve this situation, a high‐speed position sensorless FT‐DTC strategy for a six‐phase symmetrical winding PMSM with two opened phases is proposed in this study. Firstly, modified variables and a new rotating coordinate system are defined to achieve the symmetrical and decoupled mathematical model. Secondly, a stator flux observer based on the modified variables and a new coordinate system is proposed. According to the current model of modified stator flux, the estimated modified stator current can be achieved. Then, the estimated error of the modified stator current is sent to the integrator of the modified stator flux observer to correct the voltage model. Finally, the proposed stator flux observer is applied in FT‐DTC for six‐phase PMSM with two opened phases to realize the position sensorless operation at high speed. The experimental results verify the feasibility and effectiveness of the proposed strategy. [ABSTRACT FROM AUTHOR]

A smart power flow node (SPFN) aimed at a hybrid ac/dc electric power system (EPS) for future more electric aircraft is presented. The SPFN is researched to enhance the performance of the EPS. Based on the SPFN, new power flow paths are established for the EPS, and intelligent power flow management of the EPS is realised. A multi‐port topology is designed for the SPFN to be compatible with different ac and dc power ports. Moreover, three operating modes of the SPFN are studied to realise uninterrupted power supply, power support of high‐power load and power transfer of the feedback energy from regenerative load. The experimental results verify the feasibility and availability of the SPFN and show that the SPFN can improve the equivalent capacity as well as the power supply reliability of the EPS. [ABSTRACT FROM AUTHOR]

This study proposes a novel dual stator solid rotor axial flux induction motor (DSSRAFIM) for flywheel energy storage system and the computational methods for its equivalent circuit parameters. The quasi‐one‐dimensional theory and the penetration depth method assume that the electromagnetic field distribution in the solid rotor is uniformly distributed, and they are appropriate for optimal design. The multi‐layer method takes the non‐linear permeability of the solid rotor into account, and it reduces the computational effort by simplifying the complicated computation into a transfer matrix. The two‐dimensional finite element method and the three‐dimensional finite element method can provide very accurate results, but they spend a large amount of computational effort. All these methods are improved, so that they are applicable to the DSSRAFIM. Also, these methods are verified by experimental test. [ABSTRACT FROM AUTHOR]

This study proposes a novel dual stator composite rotor axial flux induction motor (DSCRAFIM) whose solid rotor is coated with copper layers. A novel multi‐slice and multi‐layer method is developed and applied to analyse the three‐dimensional electromagnetic field distribution in DSCRAFIM. In the application of this analytical method, DSCRAFIM is equivalent to a finite set of equal‐width and increasing‐length double primary composite secondary linear induction motors, whose steel secondary is divided into a finite set of equal‐height layers. The surface impedance theory is applied to derive the improved equivalent circuit model (IECM) of DSCRAFIM, which considers the coupling relationship between dual stator windings. The accuracy of this IECM is then verified by both finite‐element analysis and experimental test. [ABSTRACT FROM AUTHOR]

To adapt to the single power supply system of the aircraft, this study proposes and investigates a novel fault‐tolerant drive system based on the redundancy bridge arm for aerospace applications. The proposed fault‐tolerant drive system adopts a dual‐winding fault‐tolerant (DF) motor; the DF motor offers the advantages of magnetic isolation, physical isolation, thermal isolation, small cogging torque ripple, inhibiting the short‐circuit current and high fault tolerance. The proposed fault‐tolerant drive can adapt to the single power supply system of the aircraft, reduce the drive cost, and cut down the number of independent power sources and power switches. In addition, it can improve the power density, reliability, and the utilisation rate of the drive system. To realise the open‐circuit fault diagnosis performance, the diagnosis and processing method of the open‐circuit fault has been investigated. Then, to realise the fault‐tolerant performance, a novel space‐vector pulse‐width modulation (SVPWM) fault‐tolerant control strategy is proposed. Finally, the performances of the fault‐tolerant drive have been verified by simulations and experiments. The research results verify the reliability and effectiveness of the proposed fault‐tolerant drive system based on the redundancy bridge arm and SVPWM fault‐tolerant control strategy. [ABSTRACT FROM AUTHOR]

A virtual Hall method for sensorless control of interior permanent magnet synchronous motors (IPMSMs) using high‐frequency signal injection is presented. Based on the idea of virtual Hall, the position signal is easily estimated by comparing the magnitudes of three‐phase inductances. The experimental results prove that the proposed method has good heavy‐load operation capability with a brief control structure. [ABSTRACT FROM AUTHOR]