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Based on the potential energy method, an algorithm for modifying the meshing stiffness of helical gears is proposed. This method considers the real machining of the tooth root transition curve, which is a trajectory line formed by the tip angle of the tooth when the tool rolls into motion, and the starting point of the involute is the intersection of the tooth root transition curve and the involute. When calculating the stiffness, the tooth root transition curve equation from the root of the tooth to the starting point of the involute is used for the calculation, and the involute equation from the starting point of the involute to the top of the tooth is used in the calculation. The meshing stiffness calculated by this method is closer to the reality. Compared with the finite element method, the accuracy of the modified algorithm is verified and the calculation accuracy of the helical gear meshing stiffness is improved. Based on this method, the influence of involute shape, meshing position and contact ratio on the meshing stiffness and transmission error of helical gears is analyzed. The research results show that when the pressure angle increases, the radius of curvature of involute will increase. Thus the transverse stiffness of gears is improved. At the same time, the transverse contact ratio will firstly increase and then decrease. Under the influence of transverse stiffness and transverse contact ratio, the variation trend of average meshing stiffness is the same as that of transverse contact ratio; when the meshing position is closer to the node, the meshing stiffness will increase; an increased total contact ratio will make the average stiffness increase, and the transmission error (TE) decrease as a whole. However, when the contact ratio is close to the odd multiple of 0.5, the TE peak-to-peak value will reach a maximum value.

For ease of study and modeled training of control strategy for flexible load aggregator， an energy management and simulation system is established， which， in the light of information exchange technology featuring Reid′s subscription/publication， uses a load adjustable potential calculation method of physical model and a fast control method to support the flexible load aggregation and regulation process of power grid， realizing the automatic response and fast distribution of flexible load. The system simulates the scenario of flexible load participating in new energy consumption and power grid peak shaving and valley filling， and can be used for control strategy research and simulation to underpin flexible load aggregators to participate in power grid regulation. The system has been applied and verified in the pilot project.

Unspecific peroxygenases exhibit high activity for the selective oxyfunctionalization of inert C(sp3)-H bonds using only H2O2 as a clean oxidant, while also exhibiting sensitivity to H2O2 concentration. CdS-based semiconductors are promising for the photosynthesis of H2O2 owing to their adequately negative potential for oxygen reduction reaction via a proton-coupled electron transfer process, however, they suffer from fast H2O2 decomposition on the surface of pristine CdS. Therefore, [Cp*Rh(bpy)H2O]2+, a highly selective proton-coupled electron transfer catalyst, was anchored onto a supramolecular polymer-grafted CdS nanoflower to construct an efficient integrated photocatalyst for generating H2O2, mitigating the surface issue of pristine CdS, increasing light absorption, accelerating photonic carrier separation, and enhancing oxygen reduction reaction selectivity to H2O2. This photocatalyst promoted the light driven H2O2 generation rate up to 1345 µmol·L−1·g−1·h−1, which was 2.4 times that of pristine CdS. The constructed heterojunction photocatalyst could supply H2O2in situ for nonspecific peroxygenases to catalyze the C-H oxyfunctionalization of ethylbenzene, achieving a yield of 81% and an ee value of 99% under optimum conditions. A wide range of substrates were converted to the corresponding chiral alcohols using this photo-enzyme catalytic system, achieving the corresponding chiral alcohols in good yield (51%–88%) and excellent enantioselectivity (90%–99% ee). [ABSTRACT FROM AUTHOR]

Impaired tumor cell antigen presentation contributes significantly to immune evasion. This study identifies Berbamine hydrochloride (Ber), a compound derived from traditional Chinese medicine, as an effective inhibitor of autophagy that enhances antigen presentation in tumor cells. Ber increases MHC-I-mediated antigen presentation in melanoma cells, improving recognition and elimination by CD8+ T cells. Mutation of Atg4b, which blocks autophagy, also raises MHC-I levels on the cell surface, and further treatment with Ber under these conditions does not increase MHC-I, indicating Ber's role in blocking autophagy to enhance MHC-I expression. Additionally, Ber treatment leads to the accumulation of autophagosomes, with elevated levels of LC3-II and p62, suggesting a disrupted autophagic flux. Fluorescence staining and co-localization analyses reveal that Ber likely inhibits lysosomal acidification without hindering autophagosome–lysosome fusion. Importantly, Ber treatment suppresses melanoma growth in mice and enhances CD8+ T cell infiltration, supporting its therapeutic potential. Our findings demonstrate that Ber disturbs late-stage autophagic flux through abnormal lysosomal acidification, enhancing MHC-I-mediated antigen presentation and curtailing tumor immune escape. [ABSTRACT FROM AUTHOR]

Multienzyme cascades (MECs) have gained much attention in synthetic chemistry but remain far from being a reliable synthetic tool. Here we report a four‐enzyme cascade comprising a cofactor‐independent and a cofactor self‐sustaining bienzymatic modules for the enantioselective benzylic C−H amination of arylalkanes, a challenging transformation from bulk chemicals to high value‐added chiral amines. The two modules were subsequently optimized by enzyme co‐immobilization with microenvironmental tuning, and finally integrated in a gas‐liquid segmented flow system, resulting in simultaneous improvements in enzyme performance, mass transfer, system compatibility, and productivity. The flow system enabled continuous C−H amination of arylalkanes (up to 100 mM) utilizing the sole cofactor NADH (0.5 mM) in >90 % conversion, achieving a high space‐time yield (STY) of 3.6 g ⋅ L−1 ⋅ h−1, which is a 90‐fold increase over the highest value previously reported. [ABSTRACT FROM AUTHOR]