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To Address the issue of increased core size and weight in low-frequency transformers compared to conventional power-frequency transformers， a lightweight design method for a 35 kV low-frequency transformer is proposed. This method involves multi-objective optimization of transformer losses， weight， and dimensions. Firstly， the initial structure of the low-frequency transformer is determined based on national standards and design manuals. Subsequently， transformer size， weight， and losses are selected as optimization objectives. Following this， specific optimization variables are chosen based on the characteristics of low-frequency transformers， and corresponding constraints are defined. Finally， a genetic algorithm is utilized to optimize the low-frequency transformer. A comparative analysis reveals a reduction of 11.04% in total losses， along with a decrease of 4.36% and 6.71% in core and coil weights， respectively， and a 12.85% reduction in core center distance.

As bacterial contamination crises escalate, the development of advanced membranes possessing both high flux and antibacterial properties is of paramount significance for enhancing water sterilization efficiency. Herein, an ultrathin layer of TbPa (an imine-linked covalent organic framework) and nanosized Cu2O clusters, sequentially deposited onto polyethersulfone membranes, demonstrate exceptional water flux performance, reaching a permeance level of 16000 LHM bar−1. The deposited TbPa, generating uniformly distributed reduction sites under illumination, facilitates the uniform formation of Cu2O clusters. Furthermore, these anchored Cu2O clusters significantly optimize electron transport within the ultra-thin layer of TbPa, thereby enhancing the performance of the membrane in generating reactive oxygen species (ROS). Consequently, this membrane achieves a flux recovery rate exceeding 98.6% for flux losses caused by bacterial fouling and maintains consistent performance over 10 cycles. This work presents an effective strategy for accessing bactericidal membranes and provides insights into efficient and mild water sterilization. Water sterilization demands high flux and antibacterial membranes. Here, authors realize such membranes by coupling covalent organic frameworks and Cu2O nanoclusters. This coupling enhances the generation of reactive oxygen species under visible light, enabling fast and durable water purification. [ABSTRACT FROM AUTHOR]

BackgroundShanghai High Repetition rate XFEL and Extreme light facility (SHINE) employs a White Rabbit (WR)-based timing system. This timing system operates via the utilization of beamline–endstation division, which receives external reference timing signals and distributes them to each beamline and endstation via WR timing network devices, including master nodes, WR switches and slave nodes.PurposeThis study aims to develop a timing equipment control system (TECS) to address the requirements of remote monitoring and control of distributed timing equipment.MethodsBased on Experiment Physics and Industrial Control System (EPICS) and Simple Network Management Protocol (SNMP), an approach for acquiring timing equipment parameters was employed. These parameters was stored in the resident memory database though EPICS Input/Output Controller (IOC) and accessed via a user interface developed with PyDM (Python Display Manager). Archive and retrieval of timing equipment parameters were implemented in the Archiver Appliance historical archiving system. Finally, test environment was set up in laboratory to verify the validity and reliability of this TECS.Results & ConclusionsThis control system underwent testing exhibits its effective functionalities, including real-time monitoring equipment parameters, as well as remote control of equipment signal delay and pulse width. These capabilities are essential in meeting the requirements of SHINE beamlines and endstations.

Producing crystalline covalent organic framework (COF) films is intimately related to the elusive nucleation and growth processes, which is desirable for efficient molecular transport. Rational control over these processes and insights into the mechanisms are crucial to improve synthetic methodology and achieve COF films with regular channels. Here, we report the controllable synthesis of COF films via the temperature‐swing strategy and explore their crystallization from monomer assemblies to film formation. A detailed time‐dependent study reveals that COF crystallites preferentially coalesce at low temperature, progressing from assembled nanospheres to continuous films through lateral and vertical interactions. Moreover, appropriately elevating the synthesis temperature promotes crystal growth and eliminate the defects of weakly crystalline regions, contributing to highly crystalline and porous COF film with a surface area of 746 m2 g−1. The prepared COF composite membrane exhibits a methanol permeance of 79 L m−2 h−1 bar−1, which is 4.5 times higher than the weakly crystalline counterpart. In addition, the molecular sieving test recognize great membrane selectivity to discriminate the antibiotic mixture with a high separation factor of 15.4. This work offers a feasible way for the rational design of the synthesis environment, enabling access to highly crystalline framework materials for targeting molecular separations. [ABSTRACT FROM AUTHOR]

A straightforward asymmetric transfer hydrogenation for accessing enantiomerically enriched secondary benzyl alcohols involving free phenolic hydroxyl group(s) under mild conditions was developed. Various of optical pure aryl alcohols with a remarkable functional group compatibility were achieved with 78 %–97 % yields, 84 %–>99 % ee's and up to 10 000 TON. This rhodium‐catalyzed reaction could be performed in a gram‐scale without loss of the efficiency. Furthermore, the synthetic utility has also been demonstrated in the asymmetric synthesis of (S)‐adrenaline and (S)‐phenylephrine. [ABSTRACT FROM AUTHOR]

BackgroundShanghai High repetition rate XFEL (X-ray free electron laser) and Extreme light facility (SHINE) is a high-repetition-rate X-ray-free electron laser. The timing system of the beamlines and endstations must provide high-precision bunch IDs and a timing trigger for the equipment that works in single-pulse mode.PurposeThis study aims to design a data acquisition (DAQ) testing system to simultaneously acquire X-ray bunch IDs with their corresponding detector data package for subsequent data processing.MethodsThis DAQ testing system was developed on the Zynq UltraScale+ system-on-chip (SOC), and the White Rabbit protocol was employed for the timing system environment. A Bunch ID obtained from the FPGA mezzanine card (FMC) of the embedded White Rabbit node (WRN) was transferred to the server using a TCP protocol stack built on LwIP (light weight internet protocol). Finally, a Basler camera was employed to test this DAQ system, in which the pypylon library was applied to raw data acquisition software for camera snapshot whilst two channels of data were collected by an upper computer and saved to a database for comparison.Results & ConclusionsThe number of bunch IDs obtained by this acquisition test system is the same as that of image frames taken by Basler camera, which demonstrates that the testing system can satisfy the requirements of bunch ID acquisition in SHINE beamlines and endstations.

GSK-3β plays a critical role in regulating the Wnt/β-catenin signaling pathway, and manipulating GSK-3β in dendritic cells (DCs) has been shown to improve the antitumor efficacy of DC vaccines. Since the inhibition of GSK-3β leads to the activation of β-catenin, we hypothesize that blocking GSK-3β in DCs negatively regulates DC-mediated CD8 T cell immunity and antitumor immunity. Using CD11c-GSK-3β−/− conditional knockout mice in which GSK-3β is genetically deleted in CD11c-expressing DCs, we surprisingly found that the deletion of GSK-3β in DCs resulted in increased antitumor immunity, which contradicted our initial expectation of reduced antitumor immunity due to the presumed upregulation of β-catenin in DCs. Indeed, we found by both Western blot and flow cytometry that the deletion of GSK-3β in DCs did not lead to augmented expression of β-catenin protein, suggesting that GSK-3β exerts its function independent of β-catenin. Supporting this notion, our single-cell RNA sequencing (scRNA-seq) analysis revealed that GSK-3β-deficient DCs exhibited distinct gene expression patterns with minimally overlapping differentially expressed genes (DEGs) compared to DCs with activated β-catenin. This suggests that the deletion of GSK-3β in DCs is unlikely to lead to upregulation of β-catenin at the transcriptional level. Consistent with enhanced antitumor immunity, we also found that CD11c-GSK-3β−/− mice exhibited significantly augmented cross-priming of antigen-specific CD8 T cells following DC-targeted vaccines. We further found that the deletion of GSK-3β in DCs completely abrogated memory CD8 T cell responses, suggesting that GSK-3β in DCs also plays a negative role in regulating the differentiation and/or maintenance of memory CD8 T cells. scRNA-seq analysis further revealed that although the deletion of GSK-3β in DCs positively regulated transcriptional programs for effector differentiation and function of primed antigen-specific CD8 T cells in CD11c-GSK-3β−/− mice during the priming phase, it resulted in significantly reduced antigen-specific memory CD8 T cells, consistent with diminished memory responses. Taken together, our data demonstrate that GSK-3β in DCs has opposite functions in regulating cross-priming and memory CD8 T cell responses, and GSK-3β exerts its functions independent of its regulation of β-catenin. These novel insights suggest that targeting GSK-3β in cancer immunotherapies must consider its dual role in CD8 T cell responses. [ABSTRACT FROM AUTHOR]

An asymmetric transfer hydrogenation of 2‐oxazolones in the presence of a chiral diamine ruthenium catalyst with potassium formate as a hydrogen source and potassium carbonate as an additive in 2,2,2‐trifluoroethanol is described. A series of chiral 2‐oxazolidinones were obtained with 29%–95% yields and 86%–>99% ee's. Furthermore, gram‐scale synthesis of chiral 2‐oxazolidinone and its downstream derivatizations demonstrate the practicality of this method. [ABSTRACT FROM AUTHOR]

This paper proposes a hybrid control scheme that combines fractional-order sliding-mode control (FOSMC) with radial basis function neural network adaptive damping passivity-based control (RBFPBC) for modular multilevel converters (MMC) under non-ideal operating conditions. According to the passive control theory, we establish the Euler–Lagrange (EL) models of positive and negative sequences based on the unbalanced grid. A passivity-based controller that satisfies the energy dissipation law is designed. To enable rapid convergence of the system energy storage function, a radial basis function neural network (RBFNN) is introduced to adjust the injection damping adaptively. Additionally, a fractional-order sliding-mode controller (FOSMC) is designed. The fractional-order sliding mode surface used can improve tracking performance, and effectively suppressed the undesirable chattering phenomenon compared to the traditional sliding-mode control (SMC). Finally, combining the two control methods can effectively solve the issue of passivity-based control (PBC) being too dependent on parameters. The proposed hybrid control scheme enhances the ability of the system to resist disturbances, and improves its overall robustness. Simulation results demonstrate the feasibility and effectiveness of this control method. [ABSTRACT FROM AUTHOR]