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Preeclampsia (PE) is an obstetric disorder. N6‐methyladenosine (m6A) modification is related to PE trophoblast biological behaviors. This study explored the mechanism of m6A‐modified circSETD2 in trophoblast biological behaviors. Chorionic trophoblast apoptosis and circSETD2 expression in PE rat models were detected. HTR8/SVneo cells were induced by CoCl2 to establish PE trophoblast models. circSETD2 was silenced or overexpressed to evaluate its effect on cell proliferation, invasion, and apoptosis. m6A level of circSETD2 in trophoblasts was changed by pcDNA3.1‐METTL3 and pcDNA3.1‐FTO. The targeting relations among miR‐181a‐5p, circSETD2, and MCL1 were verified by dual‐luciferase assay. miR‐181a‐5p and MCL1 expressions were interfered with to confirm the effect of m6A‐modified circSETD2. m6A methylation level was changed in PE rats for in vivo validation. PE rats showed diminished circSETD2 expression and increased apoptosis index. circSETD2 overexpression promoted trophoblast proliferation and invasion, and reduced apoptosis. METTL3 overexpression increased total m6A, circSETD2 m6A, and circSETD2 levels. m6A modification mediated circSETD2 upregulation. circSETD2 was a sponge of miR‐181a‐5p to elevate MCL1 transcription. miR‐181a‐5p overexpression or MCL1 silencing annulled the role of m6A‐modified circSETD2. circSETD2 inhibition negated suppression of METTL3 overexpression on chorionic trophoblast apoptosis in vivo. Collectively, m6A modification of circSETD2 suppressed miR‐181a‐5p and increased MCL1 transcription, thus regulating trophoblasts. [ABSTRACT FROM AUTHOR]

High temperature superconducting (HTS) magnets often work at high energy density and have slow quench propagation speed, so a quench will present a serious risk to the safety of magnets. The quench protection method based on the dump resistance can effectively reduce the current and release the energy in the HTS magnets. However, too large dump resistance may cause excessive voltage across the magnets. A quench protection system consisting of dump resistances and metal discs has been proposed. Copper discs are often embedded in HTS magnets for conducting cooling and mechanical support. In the discharging process of HTS magnets, the copper discs can absorb energy from the magnets through magnetic coupling, thus accelerating the current decay of the magnets. This quench protection method is more effective than using dump resistance alone. In this paper, the effect of different copper discs on the discharging process of HTS coils is discussed. Eight types of copper with different residual resistivity ratios (RRR) are applied. The results show that with the increase of the RRR of the copper disc, the current decay rate of the coil increases, and the energy absorbed by the copper disc from the coil increases. The role of different copper discs in the fast quench protection of the coil can be sorted as: RRR = 300 > RRR = 100 > RRR = 80 > RRR = 60 > RRR = 40 > RRR = 30 > RRR = 20 > RRR = 10. The copper disc with RRR of 300 shows the best performance in quench protection of HTS coils. [ABSTRACT FROM AUTHOR]

Current-limiting superconducting cable uses the quench resistance of superconductor under short-circuit current to improve the short-circuit impedance of the system. In this paper, the design of current-limiting 10 kV three-phase tri-axial superconducting cable is studied. The design methods of cable conductor layer, insulation layer and current-limiting characteristics are given, and one 5 m-long sample is fabricated for testing. The sample is made of stainless-steel-reinforced yttrium barium copper oxide (YBCO) tape, with an expected rated current of 2.5 kA and rated voltage of 10 kV. The test results show that the designed cable can transmit a maximum AC current of 3.0 kA at 77 K. The cable has passed the power frequency withstand voltage, partial discharge and lightning impulse tests. The current limiting characteristics under the action of DC pulse current show that the cable can quickly quench and produce resistance, and the corresponding equivalent resistance value also changes along with current amplitude and duration. [ABSTRACT FROM AUTHOR]

The calculation of ac loss is an essential part in the thermal stability estimation of the high-temperature superconductor (HTS) superconducting magnetic energy storage system (SMES). In this paper, we propose an artificial neural network (ANN) prediction model to calculate the ac loss in real-time and apply the ANN prediction model to a 150 kJ self-made HTS SMES. The ANN prediction model is composed of a multi-scale model and an ANN. An ac loss data set calculated with the multi-scale model is used to train the ANN, and a validation data set is used to test the accuracy of the ANN after training. By comparing with the homogenization model, we find that the multi-scale model is reliable when used for ac loss calculation and suitable for building ac loss data set due to its high calculation speed. The ANN prediction model is verified to be reliable for fast estimation of the ac loss, and its accuracy improves as the scale of the training data set increases. [ABSTRACT FROM AUTHOR]

Superconducting Magnetic Energy Storage (SMES) which is characterized by its highly efficient energy storage, quick response, and power controllability, is expected to contribute to the transient stability of power system. The energy function approach is frequently used as a convenient way to control or analyse the power system. Based on the dynamic characteristic of SMES, the interaction between the SMES and the power system is analysed. According to the additional damping provided by SMES, energy function based control strategy is designed to improve the transient stability of power system. Then, the functional range of the SMES power control is analysed, which can be utilized to optimize the allocation of SMES in power system. Simulation tests are performed to evaluate the performance of the proposed energy function based control method. [ABSTRACT FROM PUBLISHER]

This paper proposes a Superconducting Magnetic Energy Storage (SMES) based excitation system for doubly-fed induction generator (DFIG) used in wind power generation. The excitation system is composed of the rotor-side converter, the grid-side converter, the dc chopper and the superconducting magnet. The superconducting magnet is connected with the dc side of the two converters, which can handle the active power transfer with the rotor of DFIG and the power grid independently. Utilizing the characteristic of high efficient energy storage and quick response of superconducting magnet, the system can be utilized to level the wind power fluctuation, alleviate the influence on power quality, and improve fault ride-through capability for the grid-connected wind farms. According to the system control objective, the system can contribute to the stability and reliability of the wind power grid-connected system. Using MATLAB SIMULINK, the model of the SMES based excitation system for DFIG is established, and the simulation tests are performed to evaluate the system performance. [ABSTRACT FROM AUTHOR]

The authors demonstrate a patterning technique, through creating via-hole structures on insulator-coated substrates via inkjet printing, the resolution of which meets the requirements for flat-panel display applications. The authors also fabricate polymer light-emitting diode arrays by subsequently inkjet printing light-emitting polymers onto the inkjet-patterned substrate. The resultant devices exhibit good performances. Hence, this nonlithographic patterning technique provides a way of patterning large-area substrates for applications such as flat-panel displays. [ABSTRACT FROM AUTHOR]

A low-power dual-mode receiver is presented for ultra-high-frequency (UHF) radio frequency identification (RFID) systems. The reconfigurable architecture of the tag is proposed to be compatible with low-power and high-sensitivity operating modes. The read range of RFID system and the lifetime of the tag are increased by photovoltaic, thermoelectric and RF energy-harvesting topology. The receiver is implemented in a 0.18-μm standard CMOS process and occupies an active area of 0.65 mm × 0.7 mm. For low-power mode, the tag is powered by the rectifier and the sensitivity is −18 dBm. For high-sensitivity mode, the maximum PCE of the fully on-chip energy harvester is 46.5% with over 1-μW output power and the sensitivity is −40 dBm with 880 nW power consumption under the supply voltage of 0.8 V. [ABSTRACT FROM AUTHOR]

Background: The role of repeat cerclage (RC) among patients with prolapsed membranes remains controversial. We aimed to investigate the effectiveness of RC and assess the correlation between clinical factors and pregnancy outcome following RC., Methods: The clinical data of patients who underwent RC for prolapsed membranes after prior cerclage were retrospectively investigated. The clinical characteristics of patients were compared between singleton and twin pregnancies. The clinical characteristics of singleton pregnancies were compared between the gestational age (GA) at delivery <28 weeks' and ≥28 weeks' groups. Receiver operating characteristic (ROC) curve analysis was performed to determine predictive factors. Singleton patients were divided into two groups according to GA at RC as follows: GA <22.3 weeks and GA ≥22.3 weeks. Pregnancy outcomes were compared between groups., Results: The mean GA at delivery of singleton pregnancies was significantly higher than that of twin pregnancies. The mean latency between RC and delivery of singleton pregnancies was significantly longer than their twin counterparts. There were significant differences in the pregnancy outcomes between the GA <22.3 weeks group and GA ≥22.3 weeks group. Kaplan-Meier survival curves showed a lower incidence of neonatal death in the GA ≥22.3 weeks group compared with that in the GA <22.3 weeks group., Conclusions: RC may be an effective method to prolong the duration of pregnancy among patients with singleton pregnancy. However, the selection of RC for patients with twin pregnancies remains controversial. GA at RC appears to be fair for predicting pregnancy outcomes following RC., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Cai, Xia and Na.)

We investigate the bleaching of two-photon absorption by single-photon excitation using femtosecond transient absorption measurements on the prototypical polyfluorene (F8), and thus introduce single-photon pumping and two-photon probing spectroscopy for the determination of absorption cross-sections in an organic semiconductor. Single-photon excitation at 3.1 eV rearranges the population distributions on the singlet excited state (1Bu) and on the ground state (1Ag), and probe pulses at 1.55 eV will thus be absorbed both by the singlet excited state through a single-photon process and by the partially depopulated ground state for two-photon transition from 1Ag to mAg. As a result, the two-photon absorption will be partially bleached, introducing a modulation to the total transient absorption. Probe intensity dependence of the transient absorption enables simultaneous determination of the two-photon absorption (mAg?1Ag) and exciton absorption (kAg?1Bu) cross-sections at 1.55 eV.