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Background and Objectives: Spinal cord injury (SCI) results in significant neurological deficits, and microglia play the critical role in regulating the immune microenvironment and neurological recovery. Protein lactylation has been found to modulate the function of immune cells. Therefore, this study aimed to elucidate the effects of glycolysis‐derived lactate on microglial function and its potential neuroprotective mechanisms via lactylation after SCI. Methods: Single‐cell RNA sequencing (scRNA‐seq) data were obtained from figshare to analyze cellular and molecular alterations within the spinal cord post‐SCI, further focusing on the expression of microglia‐related genes for cell sub‐clustering, trajectory analysis, and glycolysis function analysis. We also evaluated the expression of lactylation‐related genes in microglia between day 7 after SCI and sham group. Additionally, we established the mice SCI model and performed the bulk RNA sequencing in a time‐dependent manner. The expression of glycolysis‐ and lactylation‐related genes was evaluated, as well as the immune infiltration analysis based on the lactylation‐related genes. Then, we investigated the bio‐effects of lactate on the inflammation and polarization phenotype of microglia. Finally, adult male C57BL/6 mice were subjected to exercise first to increase lactate level, before SCI surgery, aiming to evaluate the protective effects of lactate‐mediated lactylation of microglia‐related proteins on SCI. Results: scRNA‐seq identified a subcluster of microglia, recombinant chemokine C‐X3‐C‐motif receptor 1+ (CX3CR1+) microglia, which is featured by M1‐like phenotype and increased after SCI. KEGG analysis revealed the dysfunctional glycolysis in microglia after SCI surgery, and AUCell analysis suggested that the decreased glycolysis an increased oxidative phosphorylation in CX3CR1+ microglia. Differential gene analysis suggested that several lactylation‐related genes (Fabp5, Lgals1, Vim, and Nefl) were downregulated in CX3CR1+ microglia at day 7 after SCI, further validated by the results from bulk RNA sequencing. Immunofluorescence staining indicated the expression of lactate dehydrogenase A (LDHA) in CX3CR1+ microglia also decreased at day 7 after SCI. Cellular experiments demonstrated that the administration of lactate could increase the lactylation level and inhibit the pro‐inflammatory phenotype in microglia. Functionally, exercise‐mediated lactate production resulted in improved locomotor recovery and decreased inflammatory markers in SCI mice compared to SCI alone. Conclusions: In the subacute phase of SCI, metabolic remodeling in microglia may be key therapeutic targets to promote nerve regeneration, and lactate contributed to neuroprotection after SCI by influencing microglial lactylation and inflammatory phenotype, which offered a novel approach for therapeutic intervention. [ABSTRACT FROM AUTHOR]

Aiming at the high-performance magnetic gear with 7 pole pairs of permanent magnet inner rotor and 15 pole pairs of permanent magnet outer rotor,in order to study the working principle and transmission performance,the three different running manners are discussed,their gear ratios relation are derived,and the relationship among efficiencies,torques and gear ratios are also derived. When the speeds is lower,the efficiency is almost equal to 1,thus the out torque is equal to the input torque times its gear ratio. Also,the three different running manners under lower speeds are dynamically simulated by using the finite element analysis software,and the influence of different loads on torques is obtained. Then,the input torque and output torque are measured under different loads by transmission experiment platform respectively. The results show that the input torque increases linearly with the increase of the output torque,and the ratio of output and input torque is equal to the gear ratio. All these can be used to estimate the dynamic torque when the transmission ratio is given.

In order to study the transmission performance of the COMI and CIMO type coupler with the same structure parameters,the equivalent magnetic circuit method is used to analyze and derive the torque formula of the coupler,and the final torque expression is acquired by combining the torque formula and three dimensional correction coefficient. Also,the efficiency formula of magnetic coupler is derived. Then,the finite element simulations is used to analyze the transmission performance of the two kinds of couplers when they are under the same input speeds and slips ratio. The results indicate that COMI type coupler has the same transmission efficiency with the CIMO type coupler,but can get bigger torque when they have the same geometrical parameters,which means COMI type coupler has better transmission performance.