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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]

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]

The RNA chaperone Hfq acts as a global regulator of numerous biological processes, such as carbon/nitrogen metabolism and environmental adaptation in plant-associated diazotrophs; however, its target RNAs and the mechanisms underlying nitrogen fixation remain largely unknown. Here, we used enhanced UV cross-linking immunoprecipitation coupled with high-throughput sequencing to identify hundreds of Hfq-binding RNAs probably involved in nitrogen fixation, carbon substrate utilization, biofilm formation, and other functions. Collectively, these processes endow strain A1501 with the requisite capabilities to thrive in the highly competitive rhizosphere. Our findings revealed a previously uncharted landscape of Hfq target genes. Notable among these is nifM , encoding an isomerase necessary for nitrogenase reductase solubility; amtB , encoding an ammonium transporter; oprB , encoding a carbohydrate porin; and cheZ , encoding a chemotaxis protein. Furthermore, we identified more than 100 genes of unknown function, which expands the potential direct regulatory targets of Hfq in diazotrophs. Our data showed that Hfq directly interacts with the mRNA of regulatory proteins (RsmA, AlgU, and NifA), regulatory ncRNA RsmY, and other potential targets, thus revealing the mechanistic links in nitrogen fixation and other metabolic pathways., Importance: Numerous experimental approaches often face challenges in distinguishing between direct and indirect effects of Hfq-mediated regulation. New technologies based on high-throughput sequencing are increasingly providing insight into the global regulation of Hfq in gene expression. Here, enhanced UV cross-linking immunoprecipitation coupled with high-throughput sequencing was employed to identify the Hfq-binding sites and potential targets in the root-associated Pseudomonas stutzeri A1501 and identify hundreds of novel Hfq-binding RNAs that are predicted to be involved in metabolism, environmental adaptation, and nitrogen fixation. In particular, we have shown Hfq interactions with various regulatory proteins' mRNA and their potential targets at the posttranscriptional level. This study not only enhances our understanding of Hfq regulation but, importantly, also provides a framework for addressing integrated regulatory network underlying root-associated nitrogen fixation., Competing Interests: The authors declare no conflict of interest.