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The shuttle effect significantly hinders the industrialization of high-energy-density lithium–sulfur batteries. To address this issue, NiS2/NiSe2homologous heterostructure polyhedron (HHP) composite separators were developed to immobilize polysulfides and promote their swift conversion. An in-situ visualization symmetrical cell was specifically designed to show the rapid polysulfide adsorption capability of NiS2/NiSe2HHP, while the electrolyte–separator interfacial contact behavior was simulated to elucidate the mechanism of action of the composite separator in affecting the homogeneous nucleation of lithium metal surfaces. The electrochemical experimental result highlights the substantial enhancement in the reaction kinetics of polysulfides facilitated by NiS2/NiSe2HHP, owing to its high Li+diffusion coefficient and Li2S deposition capacity. The NiS2/NiSe2HHP cells demonstrate high initial specific capacity (1224.1 mAh g–1) at 0.2 C and minimal decay rates (0.073%) at 2 C. The NiS2/NiSe2HHP separator has high electrochemical catalytic activity with multiple adsorption sites, enabling the rapid polysulfide conversion and contributing to the preparation of high-performance lithium–sulfur batteries.

In this letter, we propose a novel embedded pilot orthogonal chirp division multiplexing (OCDM) system. This system is mainly used for time-varying (TV) channels to reduce the overhead of OCDM channel estimation. In this system, a novel embedded chirp pilot arrangement in the discrete Fresnel domain with low overhead is designed. Furthermore, two channel estimation strategies are proposed for this pilot arrangement: a low-complexity data interference avoidance (IA) strategy and a higher-performance data interference suppression (IS) strategy. For the IS strategy, we also develop a novel channel estimator. Through simulation and analysis, we have demonstrated that the proposed system effectively improves the spectrum efficiency, energy efficiency, and transmission rate (SET) compared to traditional embedded pilot OCDM systems, while maintaining similar performance levels.

ABSTRACTObjective: To explore the diagnostic value of ultrasound and nerve electromyography (EMG) in the diagnosis of carpal tunnel syndrome (CTS) and its severity in the elderly. Methods: The data of 140 elderly CTS patients were retrospectively analyzed. The data of 80 patients with other diseases with similar symptoms and high suspicion of CTS during the same period were retrospectively analyzed. Pearson method was used to analyze the correlation between cross-sectional area (CSA) and motor nerve conduction velocity (MCV), distal motor latency (DML), compound muscle action potential (CMAP), sensory conduction velocity (SCV), middle-latency (ML) and sensory nerve action potential (SNAP) levels. The value of CSA, MCV, DML, CMAP, SCV, ML and SNAP in the diagnosis of CTS and its severity was analyzed by receiver operating characteristic (ROC) curve. Results: CSA in mild, moderate and severe groups was positively correlated with DML (P < 0.001) and negatively correlated with CMAP (P < 0.001). The area under the curve (AUC) values of CSA, MCV, DML, CMAP, SCV, ML and SNAP in the diagnosis of normal people and mild CTS were 0.877, 0.787, 0.921, 0.730, 0.860, 0.688 and 0.904. The AUC values of CSA, DML, CMAP, SCV, ML and SNAP in the diagnosis of mild and moderate CTS were 0.863, 0.890, 0.760, 0.848, 0.850 and 0.739, respectively. The AUC values of CSA, MCV, DML and CMAP in the diagnosis of mild and moderate CTS were 0.683, 0.660, 0.870 and 0.693. Conclusion: Ultrasound and nerve EMG are effective in the diagnosis of CTS.

A comprehensive investigation is conducted to explore the heavy-ions-induced leakage current (HIILC) modes and degradation mechanism in silicon carbide (SiC) MOSFET. The ions used in irradiation experiments had different linear energy transfer (LET) values, which aimed to simulate complex ion conditions in aerospace applications. The distinct HIILC degradation modes of SiC MOSFETs are observed first under heavy ion irradiation with different LET values. Under irradiation with low LET ions, the overall leakage current degradation is dominated by the degradation of the drain current. Conversely, gate current has a higher degradation rate under irradiation with high LET ions. The degradation mechanisms of leakage current are discussed by combining the defect analysis of irradiated samples and simulation results. We propose and verify for the first time that the generation of stacking faults (SFs) in SiC MOSFETs under heavy ion irradiation is the cause of drain current degradation regardless of LET values. Additionally, under high LET ion irradiation, damage caused by a high electric field in the gate oxide is presumed to be attributed to the rapid degradation in gate current. The proposed theory provides a foundation and guidance for reinforcing against HIILC degradation of SiC MOSFET by addressing the process and material characteristics of the SiC.

A novel optimized trench insulated-gate bipolar transistor (TIGBT) with dummy gate and buried n-type carrier stored layer (DGBN-TIGBT) is proposed and investigated in this article. The heavily doped buried n-layer embedded in the p-body region of the proposed device not only enhances the conductivity modulation in the drift region without producing a negative impact on the breakdown voltage (BV) but also forms a self-adaptive hole path through the integrated pMOS with the dummy gate (DG). Moreover, the lower p-type region is connected to the emitter via the pMOS adaptively during the switching transient, which reduces the gate-collector capacitance ( ${C} _{\text {GC}}$ ) and mitigates the accumulation of holes near the corner and bottom of the gate trench. This enables lower power loss and suppressed electromagnetic interference (EMI) noise. Simulation results show that compared with the conventional carrier stored trench bipolar transistor (CSTBT), the ON-state voltage drop ( ${V} _{\text {CE}{\text {ON}}}$ ) at a current density of 200 A/cm2 is reduced by 24.2% and ${C} _{\text {GC}}$ at ${V} _{\text {CE}}$ of 25 V is reduced by 42.6%, respectively. The turn-off loss ( ${E} _{\text {off}}$ ) is also reduced by 60.9% with the same ${V} _{\text {CE}{\text {ON}}}$ of 0.97 V. Furthermore, the reverse recovery dVAK/dt of the freewheeling diode (FWD) is dropped by 23.6% with the same turn-on loss ( ${E} _{\text {on}}$ ) of 14 mJ/cm2. Therefore, the common-mode (CM) noise can be reduced up to $12.9~\text {dB}\cdot \mu $ V for the proposed device in the frequency range of 40–100 MHz.

An ultralow loss lateral insulated gate bipolar transistor (LIGBT) with high short-circuit capability is proposed and investigated by simulations. The proposed LIGBT features integrated double pMOS at the cathode side of a conventional LIGBT (Con. LIGBT) (named as IDP LIGBT), wherein pMOS1 is the depletion mode and pMOS2 is the enhancement mode. The potential ${V}_{\text {P}}$ / ${V}_{\text {N}}$ of cathode P+/N+ regions are self-adaptively modulated by the pMOS2 and pMOS1. In theon-state, the parasitic diode ${D}1$ (p-well/cathode N+ region) of IDP LIGBT is turned on to enhance the conductivity modulation effect and then achieve a lowon-state voltage drop ( ${V}_{\text {on}}$ ). During the turning off period, the pMOS2 is turned on before the main gate of LIGBT turning off to extract holes from the p-well quickly and decrease the ${V}_{\text {P}}$ , which turns off ${D}1$ and makes less carriers needed to be extracted. Meanwhile, the pMOS1 channel is self-adaptively narrowed and depleted with the increasing ${V}_{\text {AK}}$ , which elevates the ${V}_{\text {N}}$ and then reduces the cathode electron injection efficiency. Therefore, the IDP LIGBT achieves an ultrafast switching speed and a low turnoff loss ( ${E}_{\text {off}}$ ). In the short-circuit state with high $V_{\text {AK}}$ , the pMOS1 is self-adaptively pinched off to reduce cathode electron injection efficiency and saturation current, so as to achieve a better short-circuit withstanding time ( ${t}_{\text {SC}}$ ). Compared with the MOS resistor (MR) LIGBT, the IDP LIGBT decreases the ${E}_{\text {off}}$ / ${V}_{\text {on}}$ by 55%/13% at the same ${V}_{\text {on}}$ / ${E}_{\text {off}}$ and improves the ${t}_{\text {SC}}$ by 56%.

In this letter, a novel method is proposed for accurately evaluating the transient recoverable threshold voltage (Vth) shift of silicon carbide (SiC) mosfet caused by hysteresis effect. Based on a resistive load circuit with the multistage gate drive module, the method achieves a fast switching from high-frequency bipolar switching gate bias stress to Vth acquisition. Furthermore, the method is experimentally verified with a 1200-V commercial SiC mosfet. The Vth shift is evaluated after bipolar switching stress, and the time interval between stress and measurement, i.e., the test delay, is reduced to 100 ns. In addition, the Vth shift with different test delays after 500-kHz bipolar stress is evaluated. The results demonstrate that the positive and negative Vth shifts measured after a delay time of 1 μs can be underestimated by more than 32% and 22%, respectively, when compared to a shorter test delay of 100 ns.

This article deals with a modular input-independent output-series (IIOS) multiport dc power electronic transformer (MDCPET). The IIOS structure allows for the connection of multiple dc units, such as photovoltaic (PV) arrays, storage devices, and dc loads, directly to the medium-voltage dc (MVdc) bus. This topology offers splendid galvanic isolation and less power conversion stages between dc units and the MVdc grid. Therefore, it has lower cost, and requires fewer number of low-voltage dc–dc converters and switches compared to the traditional dc distribution networks. The main challenge lies in the submodule output voltage imbalance problem of the IIOS architecture, which is caused by the varying input power of multiple dc units. To address this problem and achieve submodule output voltage equilibrium, an isolated series resonant converter is developed without the need for additional switches. In addition, the zero-voltage switching of all active switches can be achieved to improve the system efficiency. And the proposed MDCPET can operate stably in both on-grid and off-grid conditions. Finally, the six-submodule MDCPET simulations and down-scale experimental platform are carried out to verify the above theoretical analysis.

The quenching of the R-SFCLs results in the generate of a significant quantity of thermal bubbles, which will induce the breakdown of the R-SFCLs and are inherently unavoidable. The motion characteristics of the bubbles have a significant impact on the breakdown mechanism of the LN2. The objective of this paper is to study the dynamic characteristics of bubbles of different sizes in the LN2 under DC non-uniform electric field. In the experiment, the applied voltage U was set as −40 kV and −60 kV. The heat flux Hf was 8.9 W/cm2, 17.9 W/cm2 and 27.0 W/cm2, separately. A high-speed camera was used to observe the dynamic characteristics of the bubbles in different electric field. The results showed that when there was no applied voltage to the bubbles, the bubbles only move upwards. With the increase of the heat flux of the heater, the deformation rate Dr of the bubbles are nearly the same. With the applied voltage increased, the deformation rate Dr increased in the same heat flux condition. Furthermore, the deformation rate Dr also increased with the heat flux increased under the same electric field strength. The effect of the electric field on larger bubbles is more pronounced on smaller ones. Compare to the smaller bubbles, the larger bubbles have faster velocity in parallel to the electric field direction and larger deformation rate Dr. The results could help to investigate the breakdown mechanism of the bubbles and LN2 composite systems.

The construction of Schottky heterostructures of Pd NPs coupled with semiconductor NC creates a built-in electric field that promotes the adsorption and hydrogenation of NO2−and accelerates the selective conversion of NO2−to NH3.

Barrier effect is an effective way to improve the insulation strength of the resistive-type superconducting fault current limiters (R-SFCL). However, thermal bubbles generated during the quenching of the R-SFCL will induce the flashover of R-SFCLs. The objective of this paper is to investigate the DC flashover characteristics of insulation barrier-LN2-bubbles composite systems with different voltage rise rates in both polarities. In this paper, a needle-needle-plane electrode was used in the test to simulate the quenching state of a superconducting coil. A heater source which heat flux was 27 W/cm2 to generate the thermal bubbles. The high voltage was applied to one needle electrode. And the DC voltage rise rate was 0.5 kV/s, 1 kV/s and 3 kV/s, respectively. The other needle electrode and the plane electrode were connected to the ground. The results showed that with the DC voltage rise rate increases, the flashover voltage of the insulation barrier-LN2-bubbles composite systems also increases in both polarities. In the case of the bubbles, the flashover voltages are nearly the same in both polarities under the same voltage rise conditions. In the absence of bubbles, the flashover voltage of the positive polarity is higher than that in the negative polarity under the same voltage rise rate. The results can be applied to the high voltage level design of the R-SFCL.

The permanent magnet linear synchronous motor (PMLSM) significantly differs from rotary motors in constraint methods, motion characteristics, and dynamic vibration modes. This paper presents a dynamic analysis model for PMLSMs that takes into account the elastic stiffness of the guideway-slider contact surface. Hertz's contact theory is utilized to determine the elastic stiffness of the contact surface. The natural frequency considering only the mover is compared with the whole PMLSM machine considering elastic constraints. The results indicate that the analysis model considering elastic constraints can more accurately represent the dynamic characteristics of the PMLSM. Furthermore, the natural frequencies and mode shapes are obtained through experiments. The experimental results indicate that the model proposed in this paper can accurately reflect the modal vibration mode of PMLSM when considering the elastic stiffness of the contact surface.

This article investigates the multirobot task assignment problem with deadlines, where a group of distributed heterogeneous robots needs to collaborate effectively to first maximize the number of successful search and rescue missions and then minimize the robots' total service time. First, a distributed performance impact algorithm is designed to obtain the initial assignment solution, where each robot can compute its assignment solution independently. Subsequently, based on different local search strategies, a disturbance mechanism and two improvement strategies, namely, first, global task inclusion first and decoupled 1-opt second phase and, second, global task inclusion first and coupled 1-opt second phase, are proposed to disrupt and refine the initial solution. The integration of the distributed performance impact algorithm with the two refinement strategies leads to a decoupled performance impact algorithm and a coupled performance impact algorithm, respectively. Extensive numerical simulations and experiments demonstrate the superior performance of the proposed algorithms compared with the existing performance impact algorithm. If more computational running time is allowed, the resulting coupled task assignment algorithm is recommended, as it consistently provides superior solutions. Conversely, the resulting decoupled task assignment algorithm is used because it can achieve a satisfactory solution within a shorter computation time.

PMLSM (Permanent Magnet Linear Synchronous Motor) is the critical driving component for high-precision equipment. Reducing the vibration of PMLSM contributes to improving the operational performance of the equipment. The use of grain-oriented silicon steel demonstrates promising for reducing vibrations in PMLSM. However, vibration calculation methods for grain-oriented silicon steel PMLSM are currently lacking. In this paper, anisotropic material model and electromagnetic model are established to solve and analyze the electromagnetic field and magnetostriction vibration of grain-oriented silicon steel PMLSM. Vibration measurement experiments are conducted on grain-oriented silicon steel PMLSM. The experimental results show the effectiveness and accuracy of the proposed method. The research work demonstrates the effectiveness of grain-oriented silicon steel sheets in vibration reduction for PMLSM.

• A new Fe-poor high- T C Fe 14 Se 16 (tepa) 0.8 superconductor containing Fe2+, Fe3+ and Fe vacancies was synthesized. • Fe 3 Se 4 superstructures with a √2 × √2 of Fe vacancy order serve as host layers of Fe 14 Se 16 (tepa) 0.8. • Superconductivity relates with a suppression of FIM order by tuning spin states of irons. • Charge transfers between the spacer and the Fe 3 Se 4 layers result in the high- T C superconductivity. Composition/structure-dependent superconductivity for FeSe-based superconductors attracted great attention not only due to their high superconducting transition temperatures (T C), but also for understanding the origin of iron-based superconductivity. Here, we report a new Fe-poor organic-inorganic hybrid material Fe 14 Se 16 (tepa) 0.8 with a paramagnetic-diamagnetic transition at ∼42 K grown by a high-temperature organic-solution-phase method with soluble iron/selenium sources in a tepa solution, alternative to previous intercalation strategies. The Fe 14 Se 16 (tepa) 0.8 phase is in a tetragonal layered hybrid structure with a nanoplate shape. Composition analyses reveal a Fe-poor characteristic of the hybrid in contrast to previous FeSe-intercalated superconductor, and selected area electron diffraction pattern is featured by Fe 3 Se 4 superstructures with a √2 × √2 of Fe vacancy order. Ab initio density functional calculations show that minus Fe 3 Se 4 ions are stable in the hybrid and ∼0.25e−/Fe 0.75 Se is obviously larger than the reported values of approximately 0.2e−/FeSe in other FeSe-intercalated superconductors. Typical hysteresis loops and temperature dependence of dc/ac susceptibilities of the Fe 14 Se 16 (tepa) 0.8 measured below ∼42 K suggest a presence of the Meissner effect in this material. Effects of synthesis conditions on structures and magnetic properties of the hybrids show a magnetic evolution from a long-range ferrimagnetic (FIM) order of Fe 14 Se 16 (tepa) to a coexistence of FIM and superconducting (SC) orders of Fe 14 Se 16 (tepa) 0.9 and an SC order of Fe 14 Se 16 (tepa) 0.8. X-ray absorption spectrum (XAS) confirms the presence of ferric/ferrous irons. Mössbauer studies reveal that the high- T C superconductivity originates from a suppression of the FIM order through tuning the spin states of irons from high-spin Fe3+ (S = 5/2) and Fe2+ (S = 2) in the Fe 14 Se 16 (tepa) to low-spin Fe3+ (S = 1/2) and Fe2+ (S = 0) in the Fe 14 Se 16 (tepa) 0.8. Although no zero resistance is detected even at a temperature of 2 K, the resistivity at 2 K decreases by more than 1600 times compared to that in a normal state calculated by a variable range hopping (VRH) model, suggesting that the high- T C superconductivity of Fe 14 Se 16 (tepa) 0.8 is possible. [Display omitted] [ABSTRACT FROM AUTHOR]

Volume expansion of the Si-C anode during the charging/discharging process causes continuous fracture/formation of the solid electrolyte interface (SEI), which leads to rapid capacity fading. Here, we designed a MgF2-modified separator (MF-PP) to construct a fluorine-rich SEI layer by generating more LiF. The robust SEI layer formed can alleviate the volume stress and prevent crack growth in Si-C electrodes. After 450 cycles, the Si-C||MF-PP half cell retained a reversible capacity of 543.2 mAh g–1, while the LFP||MF-PP||Si-C full cell maintained a reversible capacity of 103.4 mAh g–1with high Coulombic efficiency after 100 cycles. This facile and low-cost separator modification strategy provides an easily scalable approach to develop stable Si-based anodes for next-generation high-energy-density systems.

As a simulant of hazardous 226Ra2+, the simultaneously selective and rapid elimination of radioactive 133Ba2+ions from geothermal water is necessary but still challenging. In this paper, we demonstrated the usability of a layered thiostannate with facile synthesis and inexpensive cost, namely, K2xSn4–xS8–x(KTS-3, x= 0.65–1), for the remediation of radioactive 133Ba2+in multiple conditions, including sorption isotherm, kinetics, and the influences of competitive inorganic/organic ions, pH values, and dosages. KTS-3 has a strong barium uptake ability (171.3 mg/g) and an ultrafast adsorption kinetics (about 2 min). Impressively, it can achieve a high preference for barium regardless of the excessive interference ions (Na+, K+, Mg2+, Ca2+, and humic acid) and acidic/alkaline environments, with the largest distribution coefficient Kdvalue reaching 6.89 × 105mL/g. Also, the Ba2+-laden products can be easily eluted by a concentrated KCl solution, and its adsorption performances for barium resist well even after five consecutive cycles. In addition, owing to the regular appearance and excellent mechanical strength, the prepared KTS-3/PAN (PAN = polyacrylonitrile) granule displays a good removal efficiency in the flowing ion-exchange column. These advantages mentioned above render it very promising for the effective and efficient cleanup of radioactive 133Ba2+-contaminated wastewater.

Ammonia is a potential zero-carbon fuel, and ammonia engines have also become a research hotspot for zero-carbon power systems for heavy-duty transportation equipment, such as ships, railways, and trucks. Ammonia possesses physical and chemical properties that differ significantly from those of traditional fossil fuels. The process of ammonia injection and mixture formation within the engine cylinder is complex, making it crucial to achieve optimal spray patterns and efficient combustion in ammonia engines. Most current research on ammonia engines has focused on low-pressure injection technologies; whether through intake port injection or in-cylinder injection, the practical application of high-pressure ammonia injection in actual engines still faces many technical challenges. Before the commercialization of ammonia engines, several critical technical issues must be addressed, including fuel flash boiling, mixture formation, spray collapse mechanisms, and efficient combustion. This review offers a comprehensive and systematic review of recent research trends in ammonia spray and combustion performance with the aim of providing directional guidance and a reference point for optimizing spray and combustion processes in ammonia engines.

Lenvatinib is a multiple receptor tyrosine kinases inhibitor (TKI) authorized for first-line treatment of hepatocellular carcinoma (HCC). However, Lenvatinib resistance is common in HCC clinical treatment, highlighting the urgent need to understand mechanisms of resistance. Here, we identified Golgi membrane protein 1 (GOLM1), a type II transmembrane protein originally located in the Golgi apparatus, as a novel regulator of Lenvatinib resistance. We found GOLM1 was overexpressed in Lenvatinib resistant human HCC cell lines, blood and HCC samples. Additionally, GOLM1 overexpression contributes to Lenvatinib resistance and HCC progression in vitro and in vivo. Mechanistically, GOLM1 upregulates CSN5 expression through EGFR-STAT3 pathway. Reversely, CSN5 deubiquitinates and stabilizes GOLM1 protein by inhibiting ubiquitin-proteasome pathway of GOLM1. Furthermore, clinical specimens of HCC showed a positive correlation between the activation of the GOLM1-EGFR-STAT3-CSN5 axis. Finally, GOLM1 knockdown was found to act in synergy with Lenvatinib in subcutaneous and orthotopic mouse model. Overall, these findings identify a mechanism of resistance to Lenvatinib treatment for HCC, highlight an effective predictive biomarker of Lenvatinib response in HCC and show that targeting GOLM1 may improve the clinical benefit of Lenvatinib.

•MM with t(4;14) translocation is vulnerable to class II FINs because of the upregulation of the MMSET-ACSL4-PUFAs axis.•Class II FINs and bortezomib synergize to trigger t(4;14)-positive MM cell death by attenuating glutathione levels.

In typical unsupervised domain adaptive object detection, it is assumed that extensive unlabeled training data from the target domain can be easily obtained. However, in some access-constrained scenarios, massive target data cannot be guaranteed, but acquiring only a few target samples and annotating them may costs less. Therefore, inspired by the meta-learning success in few-shot tasks, we propose an Instance-level Prototype learning Network (IPNet) for solving the domain adaptive object detection under the supervised few-shot scenario in this work. To compensate for the target domain data deficiency, we fuse cropped instances from labeled images in both domains to learn a representative prototype for each class, by enforcing features of the same class’s instances but from different domains to be as close as possible. These prototypes are further employed to discriminate various features’ salience in an image, and separate foreground and background regions for respective domain alignment. Extensive experiments are conducted on several cross-domain scenarios, and their results show the consistent accuracy gains of the IPNet over state-of-the-art methods, e.g., 10.4% mAP increase on Cityscapes-to-FoggyCityscapes setting and 3.0% mAP increase on Sim10k-to-Cityscapes setting.

The integration of orthogonal time frequency space (OTFS) and index modulation (IM) is an attractive innovation, which can meet both high throughput and low energy consumption in highly mobile scenarios. This paper presents a novel dual frequency index modulation (DFIM) scheme for OTFS to improve spectral efficiency (SE). Exploring the internal relationship between indices, the proposed scheme, termed OTFS-DFIM, turns the classic index mapping process into a cascaded procedure involving partial index mapping and index updating. The differential information between grid points in the delay-Doppler domain and the time-frequency information are utilized to jointly determine the active grid points, which enables the OTFS frame to remain sparse and results in promising bit error rate (BER) performance. We also propose three distribution modes of IM subblocks in the two-dimensional grid and analyze their impact on receiver structure and system performance. The tight closed-form expressions of BER are derived. Additionally, we evaluate existing linear/non-linear equalization algorithms in OTFS and adapt them to the OTFS-IM/OTFS-DFIM system, offering a comprehensive insight on the tradeoffs between complexity and BER performance. Numerical simulations validate the superior performance of the OTFS-DFIM scheme in both SE and BER.

This brief presents the minimum specific on-resistance ${R}_{\min ,\text {SiC}}$ of balanced symmetric 4H-silicon carbide superjunction (4H-SiC SJ) devices based on the resistance well (R-well) model. The R-well of 4H-SiC SJ is modified by considering both the anisotropy of impact ionization in the off-state and carrier incomplete ionization and JFET effect under the on-state conditions. Compared with the conventional model that only considers the breakdown voltage ${V}_{\text {B}}$ design In theoff-state, ${R}_{\min ,\text {SiC}}$ optimization achieves the minimum specific on-resistance ${R}_{\text {on},\text {sp}}$ in shorter SJ length and lower SJ doping concentration, resulting in reduced process complexity and wider process tolerance. Based on this study, a new ${R}_{\text {on},\text {sp}}~\propto ~{V}_{\text {B}}$ relationship and corresponding design formula are obtained for 4H-SiC SJ. It is shown that ${R}_{\min ,\text {SiC}}$ optimization has the potential to significantly improve the reported ${R}_{\text {on},\text {sp}}$ characteristics by 77%–92% at the same ${V}_{\text {B}}$ , providing a significant margin for further optimization.

The generation of high-intensity magnetic fields is often necessary in permanent magnet linear synchronous motor (PMLSM) systems to meet the requirements of fast response and high thrust density. However, there is currently a lack of research on the magnetic field harmonics and vibration issues that arise in PMLSM under such operating conditions. This article investigates the influence of iron core saturation on air-gap magnetic field harmonics under high-intensity magnetic fields. The impact of saturation on normal electromagnetic force harmonics is obtained by analyzing temporal and spatial harmonics of air-gap flux density and conducting analytical calculations for electromagnetic force. In addition, this article analyzes the frequency characteristics of vibrations caused by magnetostriction combined with tooth magnetic density harmonics. The theoretical results are validated through finite-element simulation and vibration experiments. A new method to reduce the vibrations of PMLSM is proposed.

As emerging and re-emerging pathogens, filoviruses, especially Ebola virus (EBOV), pose a great threat to public health and require sustained attention and ongoing surveillance. More vaccines and antiviral drugs are imperative to be developed and stockpiled to respond to unpredictable outbreaks. Virus-like vesicles, generated by alphavirus replicons expressing homogeneous or heterogeneous glycoproteins (GPs), have demonstrated the capacity of self-propagation and shown great potential in vaccine development. Here, we describe a novel class of EBOV-like vesicles (eVLVs) incorporating both EBOV GP and VP40. The eVLVs exhibited similar antigenicity as EBOV. In murine models, eVLVs were highly attenuated and elicited robust GP-specific antibodies with neutralizing activities. Importantly, a single dose of eVLVs conferred complete protection in a surrogate EBOV lethal mouse model. Furthermore, our VLVs strategy was also successfully applied to Marburg virus (MARV), the representative member of the genus Marburgvirus. Taken together, our findings indicate the feasibility of an alphavirus-derived VLVs strategy in combating infection of filoviruses represented by EBOV and MARV, which provides further evidence of the potential of this platform for universal live-attenuated vaccine development.

In this article, an electrical–thermal–mechanical (ETM) multiphysics transient finite-element (FE) model is proposed for the press-pack insulated gate bipolar transistor (PP-IGBT) module, and a targeted optimization package (TOP) is designed to enhance the short-circuit withstand capability (SCWC). First, an ETM transient FE model is proposed based on a 3.3-kV/ 50-A PP-IGBT and the coupling relation among electrical, thermal, and mechanical. The weak part of the SCWC is identified by combining the test with the simulation of the short-circuit transient process. Second, the pattern and dimension parameters of TOP are investigated to realize the best performance. Then, its SCWC improvement and reliability are verified through the SCWC, blocking voltage, and power cycling test. The SCWC of the TOP PP-IGBT has increased by over 100% compared to that of the conventional PP-IGBT.

Fe-based soft magnetic material such as amorphous or nanocrystalline alloy is an alternative to the ferrite for magnetic cores of the medium-frequency transformers (MFTs) due to its high permeability and magnetic saturation. However, accurate core loss modeling is one of the major obstacles to design a high-power-density MFT, especially when considering the nonlinearity hysteresis B-H loop. Besides, the magnetostriction that exhibits hysteresis characteristic causes the vibration issue. Several studies have proven that the high intensity of acoustic noise will do harm to the human's mental and physical health. However, the research on the modeling of the acoustic vibration caused by magnetostriction has been scarcely conducted. In this article, the Jiles–Atherton (J-A) model is applied to describe the hysteresis characteristic of the B-H and H-strain for the Fe-based soft magnetic material. The J-A magnetic and magentomechanical hysteresis models were incorporated into the finite element analysis (FEA) under the multiphysics simulation environment in order to estimate the core loss and temperature rise of the MFT. The acoustic vibration FEA model of the MFT was built based on the H-strain hysteresis J-A model. The fidelity of the simulated acoustic noise pressure was verified by the experiment test results. The proposed models in this article can be effective tools to evaluate the hysteresis magnetic and magnetomechanical behavior of the core in the MFT.

Cardiac fibrosis is a detrimental pathological process, which constitutes the key factor for adverse cardiac structural remodeling leading to heart failure and other critical conditions. Circular RNAs (circRNAs) have emerged as important regulators of various cardiovascular diseases. It is known that several circRNAs regulate gene expression and pathological processes by binding miRNAs. In this study we investigated whether a novel circRNA, named circNSD1, and miR-429-3p formed an axis that controls cardiac fibrosis. We established a mouse model of myocardial infarction (MI) for in vivo studies and a cellular model of cardiac fibrogenesis in primary cultured mouse cardiac fibroblasts treated with TGF-β1. We showed that miR-429-3p was markedly downregulated in the cardiac fibrosis models. Through gain- and loss-of-function studies we confirmed miR-429-3p as a negative regulator of cardiac fibrosis. In searching for the upstream regulator of miR-429-3p, we identified circNSD1 that we subsequently demonstrated as an endogenous sponge of miR-429-3p. In MI mice, knockdown of circNSD1 alleviated cardiac fibrosis. Moreover, silence of human circNSD1 suppressed the proliferation and collagen production in human cardiac fibroblasts in vitro. We revealed that circNSD1 directly bound miR-429-3p, thereby upregulating SULF1 expression and activating the Wnt/β-catenin pathway. Collectively, circNSD1 may be a novel target for the treatment of cardiac fibrosis and associated cardiac disease.

In this article, a parity-time-symmetric CLLC coreless transformer (CLT) with a magnetic potential balance is proposed. Compared with the conventional CLTs, it nearly achieves a unit power factor without adding any power devices, reducing the circulating conduction loss and turn-off current on the primary side. First, a complete Hamiltonian formalism describing the total energy of the transformer is established in view of the concept of the variational inverse method. Its phase-space dynamics, pseudo-Hermitian, and spectral invariance are analyzed in combination with the symmetry. Second, the two-port characteristics of the proposed CLT are discussed. The analysis results indicate that it has the same magnetic potential balance as an ideal transformer and the equivalent magnetizing inductance is maximized, achieving load-independent voltage and current conversion ratios. Additionally, the control strategy and design of a 620 W 220 V-input and 48 V-output prototype are given. Finally, a detailed experimental comparison with the conventional CLT is performed, and the peak efficiency of the prototype is 97.4%.

This study aimed to investigate the association between consumption of ultra-processed foods (UPFs) and leucocyte telomere length (LTL).

The catalytic asymmetric synthesis of silazanes is always a challenging task. Here, a highly enantioselective synthesis of silicon-stereogenic silazanes was investigated to elucidate the protocol’s principal features and to clarify the origin of the enantioselectivity by using DFT calculations. The computational results indicate that the total free energy barrier for the conversion is 19.9 kcal/mol, which is reasonable given the current reaction conditions. Consistent with the experimental findings, the calculations indicate that σ-bond metathesis (N–H bond cleavage) is the rate-determining step for this transformation. Both pathways 1 and 2 toward S- or R-configuration products were investigated computationally. We found that the main enantiomer product of this transformation is determined by the kinetically more favorable main reaction pathway 1. Calculations indicate that the loss of one or the other H on the dihydrosilane will lock the product chirality; therefore, the oxidative addition is the enantioselectivity-determining step. Non-covalent interaction (NCI) analysis confirms that a difference in steric hindrance is responsible for the enantioselectivity of the protocol. Additionally, calculations confirm that the electron-donating group on aniline appropriately lowers the free energy barrier relative to the electron-withdrawing group (ΔG= 15.5 vs 21.6 kcal/mol), thereby accelerating the conversion.

The exfoliation of violet phosphorus into violet phosphorene nanosheets (VPNS) is crucial for various applications. Large quantities of VPNS are typically prepared through solution exfoliation, but prolonged sonication often introduces extra functional groups, influencing their pristine properties. Herein, gas intercalation with thermal-cold cycles has been introduced to enhance VPNS exfoliation and minimize functionalization. The exfoliation of VPNS on the thermal-cold cycle was found to be enhanced by about 50% with helium intercalation. Excellent yield was achieved through thermal (60 °C)-cold cycle treatment in a helium atmosphere. Less functionalized or oxidized VPNS with a larger lateral size (4–7 μm) were obtained compared with those from traditional liquid exfoliation. The optical band gap of the exfoliated VPNS on thermal-cold cycling with helium intercalation was measured by optical transmission spectroscopy to be 2.15 eV, similar to that from mechanically exfoliated ones and slightly smaller than that (2.16 eV) from prolonged sonication. The assistance of gas intercalation for exfoliation was found to be consistent with theoretical prediction by density functional theory, where the penetration barrier of He (pore: 0.54 eV; interlayer: 0.14 eV) was calculated to be much lower than that of Ar (pore: 1.77 eV; interlayer: 10 eV).

In this study, we prepared bionic selenium–baicalein nanoparticles (ACM-SSe–BE) for the targeted treatment of nonsmall cell lung cancer. Due to the coating of the A549 membrane, the system has homologous targeting capabilities, allowing for the preparation of target tumor cells. The borate ester bond between selenium nanoparticles (SSe) and baicalein (BE) is pH-sensitive and can break under acidic conditions in the tumor microenvironment to achieve the targeted release of BE at the tumor site. Moreover, SSe further enhances the antitumor effect of BE by increasing the production of ROS in tumor cells. Transmission electron microscopy (TEM) images and dynamic light scattering (DLS) showed that the ACM-SSe–BE had a particle size of approximately 155 ± 2 nm. FTIR verified the successful coupling of SSe and BE. In vitro release experiments indicated that the cumulative release of ACM-SSe–BE at pH 5.5 after 24 h was 69.39 ± 1.07%, which was less than the 20% release at pH 7.4, confirming the pH-sensitive release of BE in ACM-SSe–BE. Cell uptake experiments and in vivo imaging showed that ACM-SSe–BE had good targeting ability. The results of MTT, flow cytometry, Western blot, and cell immunofluorescence staining demonstrated that ACM-SSe–BE promoted A549 cell apoptosis and inhibited cell proliferation. The in vivo antitumor results were consistent with those of the cell experiments. These results clearly suggested that ACM-SSe–BE will be a promising bionic nanosystem for the treatment of nonsmall cell lung cancer.

Lactobacillus rhamnosus(Rh) and Lactobacillus reuteri(Re) are well-known probiotic species in inflammatory bowel disease (IBD) research. The variations between these species’ efficacy against colitis, and their model of action in this regard, are intriguing and enable treatment to be individually tailored to patients. In this study, four strains each of Rh and Re were isolated from fecal samples and their draft genomes were sequenced. The anti-colitis activities of both strains involved various aspects of intestinal immune, physical, chemical, and biological barrier function. Strikingly, the tested strains exhibited considerable interspecies and intraspecies specificity in colitis amelioration. Rh strains significantly outperformed Re strains in terms of short-chain fatty acid synthesis. Nevertheless, Re strains were more effective than Rh strains in inhibiting production of inflammatory factors; promoting production of intestinal mucus, antimicrobial peptides, and tight junction proteins; and supporting the stem cell compartment. This accounts for the anti-colitis outcomes of Re strains being superior to those of Rh strains. In addition, the effective Rh and Re strains were found to express high concentrations of specific carbohydrate metabolism- and prophage-related genes, respectively. Taken together, the results of this study could assist researchers in developing effective therapies for IBD.

The mechanisms underlying the deformation and eventual destruction of Earth’s cratons remain enigmatic, despite proposed links to subduction and deep mantle plume processes. Here we study the deformation of the North China Craton using four-dimensional mantle flow models of the plate–mantle system since the late Mesozoic, integrating constraints from lithospheric deformation, mantle seismic tomography and the evolution of surface topography. We find that flat-slab subduction induced landward shortening and lithospheric thickening, while subsequent flat-slab rollback caused seaward extension and lithospheric thinning. Both subduction phases resulted in substantial topographic changes in basin sediments. Rapid flat-slab rollback, coupled with a viscosity jump and phase change across the 660 km mantle discontinuity, was a key ingredient in shaping a large mantle wedge. We argue that craton deformation through lithospheric extension and thinning was triggered by the subduction of a flat slab and its subsequent rollback. The integration of data into mechanical models provides insights into the four-dimensional dynamic interplay involving subduction, mantle processes, craton deformation and topography.

In this article, a new design method of waveguide bandpass filters (BPFs) using spoof surface plasmon polaritons (SSPPs) is proposed based on the double-layer grounded (DLG) technology. Two-layer metallic strips of the SSPP unit cells are coated on dielectric substrate and grounded to the rectangular waveguide (RWG) wall, where the substrate is inserted into the $E$ -plane of RWG. Due to the DLG structure, the capacitance coupling between two layers is introduced, and consequently the bandpass filtering responses are realized by the SSPP itself. For validation, two different types of Ka-band DLG-SSPP waveguide BPFs are presented and discussed. Their corresponding unit cells’ equivalent circuit models are extracted to clarify the filtering characteristics and transmission zero (TZ) generation. The electromagnetic (EM) simulation results show that the center frequency can be flexibly controlled by adjusting the groove length. Furthermore, in order to control the upper cutoff frequency independently, an improved structure of DLG-SSPP unit cell with central patch is also proposed. To demonstrate and verify the design feasibility, three examples of waveguide BPFs are fabricated. Good agreement between measured and simulated results show that the proposed idea will be a good candidate for the waveguide BPF design with compact size and flexibly tuning ability.

We present a novel TE20-mode 90° waveguide twist concept for millimeter-wave (mm-wave) and terahertz (THz) applications. This waveguide twist has the unique characteristic of mode filtering; that is, only the desired TE20 mode can be rotated and output, the fundamental TE10 mode, and higher order modes will be reflected. In the design, the input/output (I/O) channels are orthogonal oversized waveguides, the TE20 mode is converted into a cross-waveguide (cross-WG) with gradually changed arm lengths. Broad bandwidth (BW) and high efficiency can be easily achieved in a compact size. To verify the proposed concept, two 160–270-GHz prototypes based on rectangular waveguides (RWGs) and groove gap waveguides (GGWs) were designed, fabricated, and measured. The RWG-based prototype was milled in one metal block, while the GGW-based one was fabricated in two metal split blocks. The measured results reveal that the two prototypes achieve average insertion losses of 0.21 and 0.36 dB for the interested TE20 mode, and minimum suppressions of 45 and 35 dB for the unwanted TE10 mode over the desired frequency band. The features of polarization rotation and mode filtering make the proposed TE20-mode waveguide twist be a candidate for compact, broadband, and efficient waveguide systems.