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Cobalamin-dependent radical S-adenosyl-L-methionine protein functions with a partner to successively methylate tricyclic indole alkaloid for chuangxinmycin maturation and derivatization

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Science China Chemistry 2025年第1期68卷 308-316页

作者： Sili Wang jiancheng huang Yanan Du Wei huang Yufeng Xue Xiaokun Xu Guannan zhong Yuanyuan Shi Bin Hong Xiaoying Bian Wen Liu State Key Laboratory of Chemical Biology Shanghai Institute of Organic Chemistry University of Chinese Academy of SciencesChinese Academy of Sciences State Key Laboratory of Microbial Technology Shandong University National Health Commission (NHC) Key Laboratory of Biotechnology for Microbial Drugs Institute of Medicinal BiotechnologyChinese Academy of Medical Science & Peking Union Medical College

Cobalamin(Cbl)-dependent radical S-adenosyl-L-methionine(SAM) proteins constitute the largest collection of the radical SAM superfamily that has hundreds of thousands of individual members. Many of these proteins are involved in the biosynthesis of pharmaceutically important natural products to catalyze chemically demanding reactions. In the biosynthetic pathway of chuangxinmycin(CXM), a unique indole alkaloid antibiotic with potent anti-infective activity, functionalization of the characteristic thiopyrano[4,3,2-cd]indole scaffold by regio-and stereoselective C3-methylation is believed to rely on a Cbl-dependent radical process, which, however, remained to be reconstituted biochemically. We here report the dissection of this enzymatic process, which requires the incorporation of Cxm8, a Cbl-dependent radical SAM protein, with Cxm9, a DUF5825family protein that shares no homology to any proteins of known functions. Cxm8 and Cxm9 function together by forming an unexpected heterodimeric complex that selectively catalyzes C3-methylation of the tricyclic indole-S-hetero ring system in a successive manner, achieving CXM and a recently identified, C3-dimethylated congener. Detailed biochemical characterization,isotope labeling, structural simulation and bioinformatics analysis rationalized the catalysis of the Cxm8/Cxm9 complex and particularly the necessity of the DUF5825 protein for C3-methylase activity. This is the first example that a Cbl-dependent protein acts with a partner to exhibit radical SAM activity.

关键词： cbl-dependent radical SAM protein biosynthesis chuangxinmycin stereoselective methylation

四叉树分类的网格编码量化在SAR图像中的应用

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系统工程与电子技术 2004年第3期26卷 386-389页

作者：谢海慧纪中伟黄顺吉电子科技大学电子工程学院四川成都610054

综合了小波去相干斑噪声、四叉树分类、网格编码量化技术,提出了一种在小波域内对带噪SAR图像作网格编码量化的新方法。首先对小波域的SAR图像实施软阈值去噪声,然后根据小波图像中各子带系数的带间相关性对其进行四叉树分类,再对分类... 详细信息

综合了小波去相干斑噪声、四叉树分类、网格编码量化技术,提出了一种在小波域内对带噪SAR图像作网格编码量化的新方法。首先对小波域的SAR图像实施软阈值去噪声,然后根据小波图像中各子带系数的带间相关性对其进行四叉树分类,再对分类后的重要类小波系数应用网格编码量化形成有序的嵌入式比特流。该方法不仅利用了信号间的时间相关性,而且也较好地利用了信号变换域的相关性。并且在对SAR图像压缩的同时去除了噪声,取得了很好的效果。

关键词：图像压缩小波变换去相干斑噪声四叉树分类网格编码量化

High‑Entropy Electrode Materials:Synthesis,Properties and Outlook

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Nano-Micro Letters 2025年第1期17卷 472-506页

作者： Dongxiao Li Chang Liu Shusheng Tao jieming Cai Biao zhong jie Li Wentao Deng Hongshuai Hou Guoqiang Zou Xiaobo ji College of Chemistry and Chemical Engineering Central South UniversityChangsha 410083People’s Republic of China School of Chemistry and Chemical Engineering Hunan Institute of EngineeringXiangtan 411104People’s Republic of China

High-entropy materials represent a new category of high-performance materials,first proposed in 2004 and extensively investigated by researchers over the past two *** definition of high-entropy materials has continuously *** the last ten years,the discovery of an increasing number of high-entropy materials has led to significant advancements in their utilization in energy storage,electrocatalysis,and related domains,accompanied by a rise in techniques for fabricating high-entropy electrode ***,the research emphasis has shifted from solely improving the performance of high-entropy materials toward exploring their reaction mechanisms and adopting cleaner preparation ***,the current definition of high-entropy materials remains relatively vague,and the preparation method of high-entropy materials is based on the preparation method of single metal/low-or medium-entropy *** should be noted that not all methods applicable to single metal/low-or medium-entropy materials can be directly applied to high-entropy *** this review,the definition and development of high-entropy materials are briefly ***,the classification of high-entropy electrode materials is presented,followed by a discussion of their applications in energy storage and catalysis from the perspective of synthesis ***,an evaluation of the advantages and disadvantages of various synthesis methods in the production process of different high-entropy materials is provided,along with a proposal for potential future development directions for high-entropy materials.

关键词： High-entropy Energy storage Electrode materials

On-orbit attitude planning for Earth observation imaging with star-based geometric calibration

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Science China Technological Sciences 2025年

作者： Di huang Zhifu WANG jianya GONG Haoran ji Institute of Aerospace Science and Technology School of Remote Sensing and Information Engineering Wuhan University State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing School of Remote Sensing and Information Engineering Wuhan University National Key Laboratory of Air-based Information Perception and Fusion Intelligent Game and Decision Laboratory

To improve the quality of remote sensing images, a novel on-orbit attitude planning method for Earth observation imaging with star-based geometric calibration is presented in this study. Unlike traditional imaging processes, the proposed method includes both pre-calibration and post-calibration stages to enhance the accuracy of satellite geometric positioning. A multiple-constraint attitude planning algorithm was developed to ensure star-based calibration, wherein the satellite camera and star sensors simultaneously capture the images of stars. This integration of cameras and multiple star sensors enables effective attitude determination. During the Earth imaging stage, a fast on-orbit attitude planning algorithm was developed to determine the satellite attitude and the optimal imaging times for ground targets. Compared with existing methods, the fast on-orbit attitude planning algorithm can significantly reduce computational time and resource consumption via initial value selection and *** demonstrate the effectiveness of the proposed attitude planning method, which was successfully applied to Wuhan 1satellite.

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Smaller, faster, lower-power analog RRAM matrix computing circuits without performance compromise

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Science China(Information Sciences) 2025年

作者： Yubiao LUO Pushen ZUO Shiqing WANG zhong SUN Ru huang School of Integrated Circuits Peking University Institute for Artificial Intelligence Peking University Beijing Advanced Innovation Center for Integrated Circuits

Recently, the analog matrix computing (AMC) concept has been proposed for fast, efficient matrix operations, by configuring global feedback loops with crosspoint resistive memory arrays and operational amplifiers (OAs). The implementation of a general real-valued matrix (containing both positive and negative elements) is enabled by using a set of analog inverters,which, however, is considered inefficient regarding circuit compactness, power consumption, and temporal response. Here, with the assistance of the conductance compensation (CC) strategy to take full advantage of the inherent differential inputs of OAs,new AMC circuits without analog inverters are designed. Such a design saves the area occupation and power dissipation of analog inverters, and thus turns to be smaller and lower-power. Simulation results reveal that the new circuit also shows a faster response towards the steady state, thanks to the reduction of poles in the circuit, which, again, is contributed by the elimination of analog inverters. Along with all of these benefits, extensive simulations demonstrate that the CC-AMC circuits do not compromise the computing performance in terms of relative error caused by various non-ideal factors in the circuit.

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Nitrogen addition promotes soil carbon accumulation globally

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Science China Life Sciences 2025年第1期68卷 284-293页

作者： Xuemei Yang Suhui Ma Erhan huang Danhua Zhang Guoping Chen jiangling Zhu Chengjun ji Biao Zhu Lingli Liu jingyun Fang Institute of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking University Ministry of Education Key Laboratory for Transboundary Ecosecurity of Southwest China School of Ecology and Environmental ScienceYunnan University State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences

Soil is the largest carbon(C) reservoir in terrestrial ecosystems and plays a crucial role in regulating the global C cycle and climate *** nitrogen(N) deposition has been widely considered as a critical factor affecting soil organic carbon(SOC) storage, but its effect on SOC components with different stability remains unclear. Here, we analyzed extensive empirical data from 304 sites worldwide to investigate how SOC and its components respond to N addition. Our analysis showed that N addition led to a significant increase in bulk SOC(6.7%), with greater increases in croplands(10.6%) and forests(6.0%) compared to grasslands(2.1%). Regarding SOC components, N addition promoted the accumulation of plant-derived C(9.7%–28.5%) over microbial-derived C(0.2%), as well as labile(5.7%) over recalcitrant components(–1.2%), resulting in a shift towards increased accumulation of plant-derived labile C. Consistently, N addition led to a greater increase in particulate organic C(11.9%) than mineral-associated organic C(3.6%), suggesting that N addition promotes C accumulation across all pools, with more increase in unstable than stable pools. The responses of SOC and its components were best predicted by the N addition rate and net primary productivity. Overall, our findings suggest that N enrichment could promote the accumulation of plant-derived and non-mineral associated C and a subsequent decrease in the overall stability of soil C pool, which underscores the importance of considering the effects of N enrichment on SOC components for a better understanding of C dynamics in soils.

关键词： meta-analysis nitrogen enrichment soil organic carbon carbon accumulation carbon stability

Polarization-encoded neural networks with simplified grating patch

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Science China Technological Sciences 2025年

作者： Chengyan zhong Xiang WANG Lingfei LI Yuanchi CUI Lei XIAO Dawei SONG Junxiong GUO Wen huang Yufeng GUO Yu LIU College of Integrated Circuit Science and Engineering Nanjing University of Posts and Telecommunications National and Local Joint Engineering Laboratory of RF Integration and Micro-Assembly Technology College of Integrated Circuits Hangzhou Global Scientific and Technological Innovation Centre Zhejiang University Nanjing Mumusili Technology Co. LTD School of Integrated Circuits Tsinghua University Institute of Advanced Study School of Electronic Information and Electrical Engineering Chengdu University State Key Laboratory of Electronic Thin Films and Integrated Devices School of Integrated Circuit Science and EngineeringUniversity of Electronic Science and Technology of China

Optical neural networks (ONNs) offer a promising solution for high-performance, energy-efficient artificial intelligence hardware by leveraging the parallelism and speed of light. However, the large-scale implementation of ONNs remains challenging due to the bulky footprint and complex control of optical synapses. In this work, we propose and simulate a plasmonic polarized synaptic architecture that overcomes the diffraction limit and enables ultra-compact ONNs. By tuning the polarization state of incident light, the optical transmittance through each plasmonic unit can be dynamically adjusted to represent a synaptic weight. Our plasmonic structures, with features as small as 40 nm, operate well below this limit in the visible spectrum (400–750 nm). Compared with diffraction and interference-based circuit designs, our proposed method achieves a substantial reduction in synaptic density by factors of 150000-fold and 1500-fold, respectively. Furthermore, we successfully demonstrate a proof-of-concept plasmonic ONN applied to the Canadian Institute for Advanced Research—10classes (CIFAR-10) dataset using a Visual Geometry Group network with 16 layers (VGG16) model. After training for 80epochs, the network achieves an accuracy of 93%. The polarization-tunable plasmonics paves the way towards scalable ONNs for next-generation artificial intelligence (AI) accelerators and smart sensors.

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Hsa-miR-214-3p inhibits breast cancer cell growth and improves the tumor immune microenvironment by downregulating B7H3

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Oncology Research 2025年第1期33卷 103-121页

作者： YAN LU KANG WANG YUANHONG PENG MENG CHEN LIN zhong LUji huang FU CHENG XINDAN SHENG XIN YANG MANZHAO OUYANG GEORGE A.CALIN ZHIWEI HE China-America Cancer Research Institute Guangdong Medical UniversityDongguan523808China GCP Center Shunde HospitalSouthern Medical University(The First People’s Hospital of Shunde Foshan)Shunde528300China Department of Gastrointestinal Surgery Shunde HospitalSouthern Medical University(The First People’s Hospital of Shunde Foshan)Shunde528300China The Second School of Clinical Medicine Southern Medical UniversityGuangzhou510080China Department of Translational Molecular Pathology The University of Texas MD Anderson Cancer CenterHoustonTX 77030USA Department of Oncology Shunde HospitalSouthern Medical University(The First People’s Hospital of Shunde Foshan)Shunde528300China

Background:Immune checkpoint inhibitors play an important role in the treatment of solid tumors,but the currently used immune checkpoint inhibitors targeting programmed cell death-1(PD-1),programmed cell death ligand-1(PD-L1),and cytotoxic T-lymphocyte antigen-4(CTLA-4)show limited clinical efficacy in many breast cancers.B7H3 has been widely reported as an immunosuppressive molecule,but its immunological function in breast cancer patients remains ***:We analyzed the expression of B7H3 in breast cancer samples using data from the Cancer Genome Atlas Program(TCGA)and the Gene Expression Omnibus(GEO)*** were selected using the TarBase,miRTarBase,and miRBase *** regulatory role of the microRNA hsa-miR-214-3p on B7H3 was investigated through dual-luciferase reporter assays,which identified the specific action sites of *** expression levels of B7H3 and hsa-miR-214-3p in human breast cancer tissues and adjacent normal tissues were quantified using Western blotting and quantitative PCR(qPCR).In vitro experiments were performed to observe the effects of modulating the expression of B7H3 or hsa-miR-214-3p on breast cancer cell proliferation and ***,the regulatory impact of hsa-miR-214-3p on B7H3 was ***-linked immunosorbent assays(ELISA)and flow cytometry were employed to assess the effects of co-cultured breast cancer cells and normal human peripheral blood mononuclear cells(PBMCs)on immune cells and associated ***:In breast cancer tissues,the expression level of B7H3 is inversely correlated with that of hsa-miR-214-3p,as well as with the regulatory effects on breast cancercell ***-miR-214-3p was found to inhibit breast cancer cell growth by downregulating ***,our research identified,for the first time,two binding sites for hsa-miR-214-3p on the 3’UTR of B7H3,both of which exert similar effects ***-culture experiments revealed that hsamiR-214-3p

关键词： Breast cancer B7H3 Hsa-miR-214-3p Immunotherapy

集成深度强化学习在股票指数投资组合优化中的应用分析

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计算机科学与探索 2025年第1期19卷 237-244页

作者：冀中张文嘉天津大学电气自动化与信息工程学院天津300072 天津大学佐治亚理工深圳学院天津300072

基于集成深度强化学习的投资组合选择是当前量化金融领域的关键技术之一。然而,目前采用上一窗口阶段最优指标决定下一阶段代理的集成滚动窗口方法存在一定的滞后性。为了有效应对这一不足,提出了双层嵌套集成深度强化学习方法。该方法... 详细信息

基于集成深度强化学习的投资组合选择是当前量化金融领域的关键技术之一。然而,目前采用上一窗口阶段最优指标决定下一阶段代理的集成滚动窗口方法存在一定的滞后性。为了有效应对这一不足,提出了双层嵌套集成深度强化学习方法。该方法对三种代理(优势演员-评论员、深度确定性策略梯度和近端策略优化)进行两层嵌套模式,第一层集成通过最优化夏普比率进行阶段模型选择,第二层通过加权投票的方法集成三种深度强化学习算法,从单次训练中收集多个模型快照,在训练期间利用这些模型进行集成预测。分别对上证50投资指数和道琼斯指数及其包含的股票进行了投资组合研究,将持有指数被动策略和均值方差投资组合策略作为基线策略。实验采用了投资组合价值、年化回报率、年化波动率、最大回撤和夏普比率等指标作为对比指标。结果表明,所提出的集成方法在实用性和有效性上表现出较好的性能。

关键词：股票投资组合交易策略深度强化学习双层嵌套集成深度强化学习方法集成学习