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The structure of permanent magnet flux‐switching linear motor (PMFSLM) with permanent magnet and coil as short primary mover and slotted core as long secondary stator can solve the problem of high cost in the long‐stroke transportation field, but PMFSLM has the phenomenon of top magnetic flux leakage. The permanent magnet on the mover side of U‐shaped permanent magnet flux‐switching linear motor (UPM‐FSLM) is arranged in a U shape, which improves the utilization rate of the permanent magnet of the motor. In order to reduce the edge effect and suppress the thrust ripple, based on the size parameters of PMFSLM prototype, a UPM‐FSLM with arc‐shaped assistant permanent magnet teeth structure is proposed, its specific structure and operation mechanism are introduced; In order to obtain the optimal thrust characteristics, the Taguchi method is used to screen the arc‐shaped assistant permanent magnets teeth sensitive parameters, and then the NSGA II algorithm based on the response surface method is used for comprehensive multi‐objective optimization. The results show that compared with PMFSLM, the average thrust of the optimized motor is increased by 16.09%, and the thrust ripple is reduced by 91.78%. © 2023 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Summary: Rhizomicrobiome plays important roles in plant growth and health, contributing to the sustainable development of agriculture. Plants recruit and assemble the rhizomicrobiome to satisfy their functional requirements, which is widely recognized as the 'cry for help' theory, but the intrinsic mechanisms are still limited.In this study, we revealed a novel mechanism by which plants reprogram the functional expression of inhabited rhizobacteria, in addition to the de novo recruitment of soil microbes, to satisfy different functional requirements as plants grow. This might be an efficient and low‐cost strategy and a substantial extension to the rhizomicrobiome recruitment theory.We found that the plant regulated the sequential expression of genes related to biocontrol and plant growth promotion in two well‐studied rhizobacteria Bacillus velezensis SQR9 and Pseudomonas protegens CHA0 through root exudate succession across the plant developmental stages. Sixteen key chemicals in root exudates were identified to significantly regulate the rhizobacterial functional gene expression by high‐throughput qPCR.This study not only deepens our understanding of the interaction between the plant–rhizosphere microbiome, but also provides a novel strategy to regulate and balance the different functional expression of the rhizomicrobiome to improve plant health and growth. [ABSTRACT FROM AUTHOR]

Seed‐borne pathogens can inhabit the rhizosphere and infect the plant after germination. The rhizosphere microbiome plays critical roles in defending against seed‐borne pathogens. However, the assembly of a core rhizosphere microbiome to suppress seed‐borne pathogens is unknown. Here, the root‐associated microbiome is infested with seed‐borne Fusarium in sterile environment, while the root‐associated microbiome is not infested when it interacts with the native soil microbiome across maize cultivars, suggesting that a core rhizosphere microbiome assembles to suppress seed‐borne Fusarium. Two strategies of progressive dilution and rhizodepositional attraction are applied to identify the core rhizobacteria. A synthetic microbiota (SynM) is constructed using the isolates of the core rhizobacteria and optimized according to superior community stability and Fusarium‐suppression capability, which surpasses the single strain and randomly formed microbiota. The optimized SynM (OptSynM) presents a distinctive cooperative pattern in which a key strain harbors the Fusarium suppression function by synthesizing the antagonistic substance fengycin, while other members intensify the functional performance by promoting the growth and the expression of the antagonistic and plant‐growth‐promoting related genes of the key strain. This study demonstrates innovative approaches to construct stable and minimal microbiota for sustainable agriculture and proposes a unique cooperative pattern to sustain community stability and functionality. [ABSTRACT FROM AUTHOR]

This study presents a fault coil localisation approach for a direct‐drive permanent magnet synchronous motor (DDPMSM) with inter‐turn short‐circuit fault (ISF) using the search coil (SC) array. The SCs are wound around specific stator tooth of DDPMSM through the proposed SC array arrangement principle, which reduces the invasiveness of the fault coil localisation method. The SCs are classified as several search coil groups (SCGs), the differential between SC back electromotive forces (EMFs) in the same SCGs (δ1) and SC residual back EMF (δ2) are used as fault indicators for ISF localisation. The peak values extracted from δ1 and δ2 are the basis for diagnosing ISF. Hence, the proposed approach does not need a complicated signal processing algorithm, and it is less complex. First, the SC back EMF analytical model is developed to investigate the mapping relationship between the back EMF of each SC and fault coil location. Second, fault coil localisation indicators for ISF are analysed based on the proposed analytical model, and the exact ISF localisation approach is presented. Finally, two basic installation units and the arrangement principle of SC array in DDPMSM are proposed. Simulation and experimental results justify the effectiveness of the selected fault indicators and the feasibility of the proposed SC array for diagnosing ISF. [ABSTRACT FROM AUTHOR]

In this article, a suspension‐guided permanent magnet synchronous linear motor (SG‐PMSLM) for ropeless elevator is proposed, which can meet the requirements of high thrust and high thrust density for ropeless elevator, and reduce vibration noise and wheel‐rail wear during motor operation. The structure, working principle and electromagnetic characteristics of SG‐PMSLM are analysed. In order to improve the overall performance of SG‐PMSLM, this article aims at improving the average thrust and thrust density, reducing the thrust fluctuation of SG‐PMSLM. Firstly, the sensitivity analysis of the key structural parameters of SG‐PMSLM is conducted, and the parameters that have significant influence on the three optimisation objectives are selected as the optimisation variables. Secondly, the response surface model of three optimisation objectives is built, and the Particle Swarm Optimisation algorithm is combined to conduct the multi‐objective optimisation design for SG‐PMSLM. Thirdly, the optimised solution set is obtained for three objectives. Finite Element Analysis is used to verify that the optimised solution set has better diversity and can effectively improve SG‐PMSLM overall performance compared with the initial design. Finally, the electromagnetic performance of SG‐PMSLM is verified by experiments. [ABSTRACT FROM AUTHOR]

Permanent magnet linear synchronous motor (PMLSM) is one of the ideal driving sources of ropeless elevators. However, such motors, whether moving magnetic or moving coil, will produce the problem of excessive cost under long travel. The permanent magnet flux switched linear motor (PMFSLM) with permanent magnets (PMs) and copper coils on the mover side greatly reduces the cost. A U‐type PMFSLM is proposed in the paper. First, a PMFSLM is proposed and investigated, quantitatively comparing with PMLSM for the ropeless elevator system. Second, aiming at the problem of flux leakage at the top of PMFSLM, a U‐type PM (UPM) structure is presented. The electromagnetic performance of PMFSLM and UPM‐FSLM have been compared and summarised. The comparison results show that UPM‐FSLM solves the defect of top flux leakage, increases thrust by 4.34%, reduces thrust ripple by 28.10%, and has better electromagnetic performance than PMFSLM. Afterwards, the elevator passenger capacity of PMFSLM and UPM‐FSLM are simulated and calculated and the feasibility is analysed. Finally, a prototype of PMFSLM has been built and measured. [ABSTRACT FROM AUTHOR]

The mass production of the motors causes tolerance of shape and dimension, deviation of permanent magnet remanence and rotor eccentricity error, which affect the cogging torque and torque ripple amplitude and performance consistency. In order to reduce the torque ripple of the motor in the actual condition, the robustness optimization is performed in the paper. Firstly, an improving convex arc type permanent magnet structure is adopted to improve air gap flux density and suppress the cogging torque. Secondly, the structure parameters of the magnetic pole are selected as optimization variables, and the magnetization angle, remanence and position of the permanent magnet, static and dynamic rotor eccentricity are considered as noise factors. To improve the overall robustness of the motor under different operating conditions, the dynamic Taguchi method is used to optimize the robustness of the motor, and the test data is processed through the relation analysis method to obtain the optimal combination of control factors. Finally, the prototype is manufactured for the experiment. Compared with the single‐operating conditions robust optimization results, the robust optimization method improves the robustness of the motor. The cogging torque amplitude is reduced by 39.2%. The torque ripple is 38.4% lower than that before optimization. [ABSTRACT FROM AUTHOR]

This paper studies a superconducting maglev submersible cryogenic liquid pump (CLP) using superconducting magnetic bearing (SMB). A new structure is proposed for the self‐stability of high‐temperature superconducting magnetic levitation, and the compact structure of disk motor‐pump. The rotor of the axial‐flux disk motor is connected with a centrifugal impeller to form an impeller‐rotor of the proposed superconducting CLP. Supported by a SMB system, the impeller‐rotor rotates frictionlessly with self‐stabilisation as a suspension rotor. The SMB system includes a radial‐type SMB, an auxiliary permanent magnet bearing, and an electromagnetic bearing composed of the stator and the rotor of disk motor. Theoretical calculations and experimental measurements are performed to examine the axial and radial levitation force behaviours of the SMB system. Then, a kinetic model of the suspension rotor is established and analysed to assure force balance and stable levitation. Finally, a prototype pump is fabricated and an experimental setup for liquid nitrogen transmission is constructed for validation purposes. The experimental tests on the pump head and the flow rate are carried out, which demonstrate the effectiveness of the proposed superconducting maglev submersible CLP. [ABSTRACT FROM AUTHOR]

Rhizosphere microorganisms interact with plant roots by producing chemical signals that regulate root development. However, the distinct bioactive compounds and signal transduction pathways remain to be identified. Here, we showed that sesquiterpenes are the main volatile compounds produced by plant‐beneficial Trichoderma guizhouense NJAU4742. Inhibition of sesquiterpene biosynthesis eliminated the promoting effect of this strain on root growth, indicating its involvement in plant‐fungus cross‐kingdom signalling. Sesquiterpene component analysis identified cedrene, a highly abundant sesquiterpene in strain NJAU4742, to stimulate plant growth and root development. Genetic analysis and auxin transport inhibition showed that the TIR1 and AFB2 auxin receptors, IAA14 auxin‐responsive protein, and ARF7 and ARF19 transcription factors affected the response of lateral roots to cedrene. Moreover, the AUX1 auxin influx carrier and PIN2 efflux carrier were also found to be indispensable for cedrene‐induced lateral root formation. Confocal imaging showed that cedrene affected the expression of pPIN2:PIN2:GFP and pPIN3:PIN3:GFP, which might be related to the effect of cedrene on root morphology. These results suggested that a novel sesquiterpene molecule from plant‐beneficial T. guizhouense regulates plant root development through the transport and signalling of auxin. Summary Statement: From the volatile compounds produced by a plant beneficial fungus, we identified a novel component cedrene that can promote plant root development. We revealed the role of auxin signalling and transport in the process of cedrene‐promoted root development. This study complements the lack of identification of distinct bioactive compounds from microbial sources and provides a helpful tool to study and decipher the underlying cellular and molecular reactions and mechanism occurring in microbe‐plant interactions. [ABSTRACT FROM AUTHOR]

A permanent magnet synchronous motor (PMSM) is introduced with 120° phase belts toroidal windings (PBTWs) (120°PBTWPMSM), in which its armature reaction field principle is elaborated. Then, the experiment concerning the 120°PBTWPMSM is conducted to verify the validity of the related analysis and the feasibility of the 120°PBTWPMSM. In addition, a method of shifting the magnetic poles (SMP) is adopted to suppress the cogging torque and the torque ripple. After this, the 120°PBTWPMSM after SMP is further optimised by the Taguchi method to obtain the structural parameters of the motor with optimal comprehensive performance. Finally, the performance of the original motor, the 120°PBTWPMSM after SMP and the optimal motor are compared, which verify the effectiveness of the optimization methods. [ABSTRACT FROM AUTHOR]

Efficient root colonization of plant growth‐promoting rhizobacteria is critical for their plant‐beneficial functions. However, the strategy to overcome plant immunity during root colonization is not well understood. In particular, how Bacillus strains cope with plant‐derived reactive oxygen species (ROS), which function as the first barrier of plant defence, is not clear. In the present study, we found that the homolog of flg22 in Bacillus velezensis SQR9 (flg22SQR9) has 78.95% identity to the typical flg22 (flg22P.s.) and induces a significant oxidative burst in cucumber and Arabidopsis. In contrast to pathogenic or beneficial Pseudomonas, live B. velezensis SQR9 also induced an oxidative burst in cucumber. We further found that B. velezensis SQR9 tolerated higher H2O2 levels than Pst DC3000, the pathogen that harbours the typical flg22, and that it possesses the ability to suppress the flg22‐induced oxidative burst, indicating that B. velezensis SQR9 may exploit a more efficient ROS tolerance system than DC3000. Further experimentation with mutagenesis of bacteria and Arabidopsis showed that the two‐component regulatory system, ResDE, in B. velezensis SQR9 is involved in tolerance to plant‐derived oxidative stress, thus contributing to root colonization. This study supports a further investigation of the interaction between beneficial rhizobacteria and plant immunity. The beneficial rhizobacterium Bacillus velezensis SQR9 or its flg22 peptides triggered oxidative burst in cucumber and Arabidopsis. The two‐component regulatory system, ResDE, in B. velezensis SQR9 is involved in tolerance to plant‐derived oxidative stress, thus contributing to root colonization. [ABSTRACT FROM AUTHOR]

The phytohormone indole‐3‐acetic acid (IAA) has been demonstrated to contribute to the plant growth‐promoting effect of rhizobacteria, but the IAA biosynthesis pathway in rhizobacteria remains unclear. The ysnE gene, encoding a putative tryptophan acetyltransferase, has been demonstrated to be involved in and strongly contribute to IAA production in Bacillus, but the mechanism is unknown. In this study, to investigate how ysnE participates in IAA biosynthesis in the plant growth‐promoting rhizobacterium Bacillus amyloliquefaciens SQR9, differences in the produced IAA biosynthesis intermediates between wild‐type SQR9 and ΔysnE were analyzed and compared, and the effects of different intermediate compounds on the production of IAA and the accumulation of other intermediates were also investigated. The results showed that the mutant ΔysnE produced more indole‐3‐lactic acid (ILA) and tryptamine (TAM) than the SQR9 wild‐type strain (nearly 1.6‐ and 2.1‐fold), while the production of tryptophol (TOL) was significantly decreased by 46%. When indole‐3‐pyruvic acid (IPA) served as the substrate, the concentration of ILA in the ΔysnE fermentation broth was much higher than that of the wild type, while IAA and TOL were significantly lower, and ΔysnE was lower than SQR9 in IAA and TOL with the addition of TAM. The TOL content in the ΔysnE fermentation broth was much lower than that in the wild‐type SQR9 with the addition of ILA. We suggest that ysnE may be involved in the IPA and TAM pathways and play roles in indole acetaldehyde (IAAld) synthesis from IPA and TAM and in the conversion of ILA to TOL. [ABSTRACT FROM AUTHOR]

Summary: Deciphering the complex cellular behaviours and advancing the biotechnology applications of filamentous fungi increase the requirement for genetically manipulating a large number of target genes. The current strategies cannot cyclically coedit multiple genes simultaneously. In this study, we firstly revealed the existence of diverse homologous recombination (HR) types in marker‐free editing of filamentous fungi, and then, demonstrated that sgRNA efficiency‐mediated competitive inhibition resulted in the low integration of multiple genetic sites during coediting, which are the two major obstacles to limit the efficiency of cyclically coediting of multiple genes. To overcome these obstacles, we developed a biased cutting strategy by Cas9 to greatly enhance the desired HR type and applied a new selection marker labelling strategy for multiple donor DNAs, in which only the donor DNA with the lowest sgRNA efficiency was labelled. Combined with these strategies, we successfully developed a convenient method for cyclically coediting multiple genes in different filamentous fungi. In addition, diverse HRs resulted in a useful and convenient one‐step approach for gene functional study combining both gene disruption and complementation. This research provided both a useful one‐step approach for gene functional study and an efficient strategy for cyclically coediting multiple genes in filamentous fungi. [ABSTRACT FROM AUTHOR]

Lateral root formation is coordinated by both endogenous and external factors. As biotic factors, plant growth‐promoting rhizobacteria can affect lateral root formation, while the regulation mechanism is unclear. In this study, by applying various marker lines, we found that volatile compounds (VCs) from Bacillus amyloliquefaciens SQR9 induced higher frequency of DR5 oscillation and prebranch site formation, accelerated the development and emergence of the lateral root primordia and thus promoted lateral root development in Arabidopsis. We demonstrated a critical role of auxin on B. amyloliquefaciens VCs‐induced lateral root formation via respective mutants and pharmacological experiments. Our results showed that auxin biosynthesis, polar transport and signalling pathway are involved in B. amyloliquefaciens VCs‐induced lateral roots formation. We further showed that acetoin, a major component of B. amyloliquefaciens VCs, is less active in promoting root development compared to VC blends from B. amyloliquefaciens, indicating the presence of yet uncharacterized/unknown VCs might contribute to B. amyloliquefaciens effect on lateral root formation. In summary, our study revealed an auxin‐dependent mechanism of B. amyloliquefaciens VCs in regulating lateral root branching in a non‐contact manner, and further efforts will explore useful VCs to promote plant root development. The volatile compounds from Bacillus spp. increase the frequency of prebranch site formation and further accelerated the emergence of lateral root primordia (LRP) from the primary root (PR) in Arabidopsis, resulting in a denser lateral root (LR) along the PR spatially. This process is dependent on auxin signaling pathway; fully functional machinery of YUCs‐mediated auxin biosynthesis and polar auxin transport are also required. [ABSTRACT FROM AUTHOR]

Inter‐turn short‐circuit fault (ISF) degrades its reliability and may cause serious catastrophes for direct‐drive permanent magnet synchronous motor (DDPMSM). Fault location technology can reduce maintenance time, increase the mean time between failure (MTBF), and then improve the reliability of DDPMSM. Hence, an intelligent fault locating system for DDPMSM is proposed in this paper. This system proposes a knowledge graph (KG) based diagnostic tool for detection and location of the fault coil. First, the fault model of the DDPMSM with multiple branches parallel winding is established, which is used to analyze the fault characteristics of motor. Second, the BDC and BRC are proposed as the fault indicator. The effectiveness and robustness of fault indicator are analyzed. Then, the KG system are designed and established according to the relationship between fault indicator and location of fault coil. Finally, the system is tested by data under different fault and operation conditions. The test results showed that the proposed fault locating system can detect and locate the fault coil in early stage. The minimum ratio of shorted turns to branch turns that can be detected is 0.52%. The minimum ratio of shorted turns to branch turns that can be located is 6.25%. [ABSTRACT FROM AUTHOR]

Owing to its many benefits, including convenient and short computing time, the analytical model (AM) is widely used in the performance analyse of the permanent magnet synchronous motor (PMSM). The existing analytical models based on phase winding cannot sufficiently speculate about the contribution of the coil to the performances of direct‐drive PMSM (DDPMSM) with series coils and multiple branches. Hence, in this work, a novel AM for the DDPMSM is proposed. This model, which is based on the winding sub‐element, can analyse the influence of coil on motor performance. First, the structure and key parameters of the DDPMSM are reported. Second, an inductance matrix, which considers the spatial disposition of coils and the characteristics of large self‐inductance and small mutual inductance, is constructed. Then, the influence of the coil on motor performance is analysed based on the proposed AM. Finally, the results of AM, finite‐element model and experiment are compared. The results validate the correctness of the proposed AM. Furthermore, the proposed AM can speculate about the contribution of a coil in the DDPMSM performances with satisfactory accuracy. [ABSTRACT FROM AUTHOR]

The special structure of the two‐degrees‐of‐freedom direct drive induction motor (2DoFDDIM) gives rise to the magnetic‐coupling between the rotary and linear magnetic fields. In this article, the dynamic magnetic‐coupling effect, which is against the static coupling effect and indicates the special phenomenon caused by coupling magnetic fields in helical motion, is exposed and investigated based on the 3D finite‐element model (3D FEM). The control variable method is adopted and only the coupling magnetic field in helical motion is considered in this research. The performance changes caused by the dynamic magnetic‐coupling effect of the motor are simulated and analyzed. The relationship between the coupling magnetic field and the dynamic magnetic‐coupling effect is disclosed. To validate the 3D FEM and the magnetic‐coupling effect of 2DoFDDIM, a prototype and an experimental platform were built and measured. For the induced voltages caused by the magnetic‐coupling effect, the finite element analysis results are in agreement with the experimental results. © 2019 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

Summary: Chemotaxis to plant root exudates is supposed to be a prerequisite for efficient root colonization by rhizobacteria. This is a highly multifactorial process since root exudates are complex compound mixtures of which components are recognized by different chemoreceptors. Little information is available as to the key components in root exudates and their receptors that drive colonization related chemotaxis. We present here the first global assessment of this issue using the plant growth‐promoting rhizobacterium (PGPR) Bacillus velezensis SQR9 (formerly B. amyloliquefaciens). This strain efficiently colonizes cucumber roots, and here, we show that chemotaxis to cucumber root exudates was essential in this process. We conducted chemotaxis assays using cucumber root exudates at different concentrations, individual exudate components as well as recomposed exudates, taking into account their concentrations detected in root exudates. Results indicated that two key chemoreceptors, McpA and McpC, were essential for root exudate chemotaxis and root colonization. Both receptors possess a broad ligand range and recognize most of the exudate key components identified (malic, fumaric, gluconic and glyceric acids, Lys, Ser, Ala and mannose). The remaining six chemoreceptors did not contribute to exudate chemotaxis. This study provides novel insight into the evolution of the chemotaxis system in rhizobacteria. [ABSTRACT FROM AUTHOR]

Two degree‐of‐freedom direct drive induction motor (2DoFDDIM), capable of rotary, linear and helical motion, has widespread application. A new mover structure is proposed, which is made from a hollow cylinder with copper cast in the axial slots and the circumferential slots on its surface. Then, three‐dimensional finite element models of 2DoFDDIM are used to determine the performances of rotary, linear and helical motion developed by the motor. The results show that the new mover has a great improvement on the motor performances of all modes of motions compared with the initial mover. The researches on mover structure and characteristics of 2DoFDDIM present a new path of optimisation on 2DoFIM. [ABSTRACT FROM AUTHOR]

This study presents a composite multilayer method (CMM) to evaluate the performance of a two‐degree‐of‐freedom (2DoF) direct drive induction motor (2DoFDDIM) whose solid rotor is coated with a copper layer. It includes a rotary part and a linear part. Based on the traditional multilayer theory, a complete 2DoFDDIM CMM computer program importing propagation constants is built. Due to the complex magnetic field in a 2DoFDDIM, this study mainly analyses it from the perspective of a single DOF motor. An equivalent circuit for the rotary part of the 2DoFDDIM is then derived applying CMM and the 2D magnetic field distribution is obtained by solving Maxwell's equations in motor layers. The developed torques, power factors and stator currents of the rotary part with different slips and the latter two of the linear part at zero speed are calculated by CMM, which are then compared with results from the finite element method (FEM) and experimental results. The computation time of the CMM is far less than that of the FEM. The acceptable accuracy confirms the effectiveness of the CMM for analysis and performance calculations of the 2DoFDDIM. [ABSTRACT FROM AUTHOR]