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Cysteine plays a pivotal role in the sulfur metabolism network of plants, intimately influencing the conversion rate of organic sulfur and the plant's capacity to withstand abiotic stresses. In tea plants, the serine acetyltransferase (SAT) genes emerge as a crucial regulator of cysteine metabolism, albeit with a notable lack of comprehensive research. Utilizing Hidden Markov Models, we identified seven CssSATs genes within the tea plant genome. The results of the bioinformatics analysis indicate that these genes exhibit an average molecular weight of 33.22 kD and cluster into three distinct groups. Regarding gene structure, CssSAT1 stands out with ten exons, significantly more than its family members. In the promoter regions, cis-acting elements associated with environmental responsiveness and hormone induction predominate, accounting for 34.4% and 53.1%, respectively. Transcriptome data revealed intricate expression dynamics of CssSATs under various stress conditions (e.g., PEG, NaCl, Cold, MeJA) and their tissue-specific expression patterns in tea plants. Notably, qRT-PCR analysis indicated that under salt stress, CssSAT1 and CssSAT3 expression levels markedly increased, whereas CssSAT2 displayed a downregulatory trend. Furthermore, we cloned CssSAT1-CssSAT3 genes and constructed corresponding prokaryotic expression vectors. The resultant recombinant proteins, upon induction, significantly enhanced the NaCl tolerance of Escherichia coli BL21, suggesting the potential application of CssSATs in bolstering plant stress resistance. These findings have enriched our comprehension of the multifaceted roles played by CssSATs genes in stress tolerance mechanisms, laying a theoretical groundwork for future scientific endeavors and research pursuits. [ABSTRACT FROM AUTHOR]

Multiple disturbances coming from friction, matched, and mismatched uncertainties make it difficult for electrohydraulic servosystems to obtain the satisfactory position-tracking performance. The existing adaptive backstepping controllers fail to effectively distinguish the difference of disturbance between the mechanical subsystem and the hydraulic subsystem, which limits the compensation effect of multiple disturbances, especially for friction nonlinearity. Therefore, the adaptive backstepping-extended state observer position-tracking controller combined with compound friction compensation is proposed to simultaneously compensate for the fast-varying friction disturbance of a mechanical subsystem and the slow-varying matched disturbance of a hydraulic subsystem. The extended state observer algorithm is integrated into the adaptive backstepping controller to suppress the null bias of the average tracking error. The compound friction compensation includes a LuGre model-based compensation and a high-order disturbance observer, which can improve the tracking performance of system and avoids the excessive gain of observer. A large number of comparative experiments are conducted to verify the effective of the proposed controller. [ABSTRACT FROM AUTHOR]

To study the change of grain size for the hot extrusion deformation of half shaft bushing,according to the dynamic recrystallization theory,the paper establishes the dynamic recrystallization model of material and uses the finite element analysis software Deform-3 D to study the shape of half shaft bushing in the mold work under the condition of different variation of hot extrusion deformation process of material grain size. The results show that while doing the extrusion in the shape of straight line and circular arc and spline curve with three kinds of work,the grain sizes are at different levels of detail. The circular mold material makes grain size smaller and more symmetrical. The result has important significance on the improvement of performance and quality of the sleeve.

Breaking the trade‐off between activity and selectivity has perennially been a formidable endeavor in the field of hydrogen peroxide (H2O2) photosynthesis, especially the side‐on configuration of oxygen (O2) on the catalyst surface will cause the cleavage of O−O bonds, which drastically hinders the H2O2 production performance. Herein, we present an atomically heteroatom P doped ZnIn2S4 catalyst with tunable oxygen adsorption configuration to accelerate the ORR kinetics essential for solar‐driven H2O2 production. Indeed, the spectroscopy characterizations (such as EXAFS and in situ FTIR) and DFT calculations reveal that heteroatom P doped ZnIn2S4 at substitutional and interstitial sites, which not only optimizes the coordination environment of Zn active sites, but also facilitates electron transfer to the Zn sites and improves charge density, avoiding the breakage of O−O bonds and reducing the energy barriers to H2O2 production. As a result, the oxygen adsorption configuration is regulated from side‐on (Yeager‐type) to end‐on (Pauling‐type), resulting in the accelerated ORR kinetics from 874.94 to 2107.66 μmol g−1 h−1. This finding offers a new avenue toward strategic tailoring oxygen adsorption configuration by the rational design of doped photocatalyst. [ABSTRACT FROM AUTHOR]

Constructing rich defect active site structure for material design is still a great challenge. Herein, a simple surface engineering strategy is demonstrated to construct one‐unit‐cell ZnIn2S4 atomic layers with the modulated surface energy of S vacancy. Rich surface energy can regulate and control the rich S vacancy, which ensures rich active sites, higher charge density and effective carrier transport. As a result, the ZnIn2S4 atomic layers with rich surface energy affords an obvious enhancement in H2O2 productive rate of 1592.04 µmol g−1 h−1, roughly 14.58 times superior to that with poor surface energy. Moreover, the in situ infrared diffuse reflection spectrum indicates that S vacancy as the oxygen reduction reaction active site is responsible for the critical intermediate *O2− and *OOH, corresponding to two‐electron oxygen reduction reaction. This study provides a valuable insight and guidance for constructing controllably defects to achieve highly efficient H2O2 production. [ABSTRACT FROM AUTHOR]