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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 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.

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Solution‑Processed Thin Film Transparent Photovoltaics:Present Challenges and Future Development

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Nano-Micro Letters 2025年第2期17卷 566-600页

作者： Tianle liu Munerah M.S.Almutairi Jie Ma Aisling Stewart Zhaohui Xing Mengxia liu Bo Hou Yuljae Cho UM-SJTU Joint Institute Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China School of Physics and Astronomy Cardiff UniversityCardiff CF243AAWalesUK Department of Electrical and Computer Engineering Yale UniversityNew HavenCT 06511USA Energy Sciences Institute Yale UniversityWest HavenCT 06516USA Future Photovoltaics Research Center Global Institute of Future TechnologyShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China

Electrical energy is essential for modern society to sustain economic *** soaring demand for the electrical energy,together with an awareness of the environmental impact of fossil fuels,has been driving a shift towards the utilization of solar ***,traditional solar energy solutions often require extensive spaces for a panel installation,limiting their practicality in a dense urban *** overcome the spatial constraint,researchers have developed transparent photovoltaics(TPV),enabling windows and facades in vehicles and buildings to generate electric *** TPV advancements are focused on improving both transparency and power output to rival commercially available silicon solar *** this review,we first briefly introduce wavelength-and non-wavelengthselective strategies to achieve *** of merit and theoretical limits of TPVs are discussed to comprehensively understand the status of current TPV *** we highlight recent progress in different types of TPVs,with a particular focus on solution-processed thin-film photovoltaics(PVs),including colloidal quantum dot PVs,metal halide perovskite PVs and organic *** applications of TPVs are also reviewed,with emphasis on agrivoltaics,smart windows and ***,current challenges and future opportunities in TPV research are pointed out.

关键词： Transparent semiconductors Solution-processable transparent solar cell Emerging solar cell materials Buildingintegrated photovoltaics

Distributed fiber optic sensing system for vibration monitoring of 3D printed bridges

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Optoelectronics Letters 2025年第1期21卷 28-34页

作者： ZHAO Shuai ZHOU Ran LUO Mingming liu Jianfei liu Xiongfei ZHOU Tao School of Electronic Information Engineering Hebei University of Technology Tianjin Key Laboratory of Electronic Materials and Devices School of Civil Engineering and Transportation Hebei University of Technology Tianjin Jinhang Institute of Technical Physics

The fiber optic sensing technology provides data support in structural health monitoring of the macro facilities, including design, construction, and maintenance of bridges, tunnels, ports and other infrastructures. In this paper, a distributed vibration sensing system is proved to be responsive to a single touch over a 1.8-m-long equivalent fiber segment, covering a vibration frequency from 5 Hz to 25 kHz. The sensing fiber was arranged as an S type layout on the bridge to recognize the standing state, windblown disturbance, and walking vibration. Moreover, the knocking and climbing events are recognized fiber laying spinning lines and hanging on the fences, respectively. The demonstration shows an accurate positioning and sensitive vibration monitoring applied on the automated three-dimensional(3D) printed bridge, which is applicable to all kinds of 3D printed facilities as intelligent sensory neuro-networks.

关键词： Spinning (fibers)

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含有源频率选择表面可调复合吸波体

物理学报 2011年第7期60卷 270-274页

作者：陈谦江建军别少伟王鹏刘鹏徐欣欣华中科技大学电子科学与技术系武汉430074

基于传输线等效理论,设计了含有源频率选择表面(active frequency selective surface,AFSS)的三层可调复合吸波体,第一层是表面层,为AFSS衬底;中间层是AFSS层,由频率选择表面(frequency selective surface,FSS)和PIN二极管阵列构成;第... 详细信息

基于传输线等效理论,设计了含有源频率选择表面(active frequency selective surface,AFSS)的三层可调复合吸波体,第一层是表面层,为AFSS衬底;中间层是AFSS层,由频率选择表面(frequency selective surface,FSS)和PIN二极管阵列构成;第三层是介质层.反射率测量结果表明,通过调节PIN二极管阵列偏置电压可以动态调节吸波体反射特性,在偏置电压为5V时,可获得最佳吸波性能,在5—15GHz和5.3—13GHz频段分别可获得-8dB和-10dB以下吸波效果.采用贴片电阻取代PIN二极管进一步验证了结果的可靠性.

关键词：频率选择表面复合吸波材料反射率 PIN二极管

A quantum-search-based multi-classifier for image recognition

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 21-31页

作者： Lu liu Xingyu Wu Lufan Zhang Chuan Wang School of Artificial Intelligence Beijing Normal University Applied Optics Beijing Area Major Laboratory Beijing Normal University

The multi-class classification of images is a pivotal challenge within the realm of image processing. As the volume of visual data continues to expand, there is a burgeoning interest in harnessing the unique capabilities of quantum computation to augment the efficiency of classification tasks. However, many existing methods for training quantum image multi-classifiers parallel classical machine learning techniques, where the requisite circuit measurements increase linearly with the volume of training data. This work introduces a novel approach for training a quantum image multi-classifier based on the quantum search algorithm. We have meticulously conducted rigorous experiments on a handwritten digit dataset, a classic benchmark in the field. The results have been meticulously compared with previous works, and the comparative analysis not only validates the efficiency of our proposed approach, requiring only O(N/b) measurements during training, but also highlights a significant quadratic speedup of the algorithm.

关键词： quantum computation image recognition quantum search algorithm

Engineering atomic Rb-N configurations to tune radical pathways for highly selective photocatalytic H2O2 synthesis coupled with biomass valorization

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Journal of Energy Chemistry 2025年第1期100卷 215-225页

作者： Jiaye Li Shuang Pan Yihuang Chen Qiong liu College of Chemistry and Materials Engineering Wenzhou University Guangdong Provincial Key Laboratory of Chemical Measurement and Emergency Test Technology (China) Institute of Analysis Guangdong Academy of Sciences (China National Analytical CenterGuangzhou)

Photocatalytic oxygen reduction for hydrogen peroxide （H2O2） synthesis presents a green and costeffective production ***,achieving highly selective H2O2synthesis remains challenging,necessitating precise control over free radical reaction pathways and minimizing undesirable oxidative ***,we report for the visible light-driven simultaneous co-photocatalytic reduction of O2to H2O2and oxidation of biomass using the atomic rubidium-nitride modified carbon nitride（CNRb）.The optimized CNRb catalyst demonstrates a record photoreduction rate of 8.01 mM h-1for H2O2generation and photooxidation rate of 3.75 mM h-1for furfuryl alcohol to furoic acid,achieving a remarkable solar-to-chemical conversion （SCC） efficiency of up to 2.27%.Experimental characterizations and DFT calculation disclosed that the introducing atomic Rb–N configurations allows for the high-selective generation of superoxide radicals while suppressing hydroxyl free radical *** is because the Rb–N serves as the new alternative site to perceive a stronger connection position for O2adsorption and reinforce the capability to extract protons,thereby triggering a high selective redox product *** study holds great potential in precisely regulating reactive radical processes at the atomic level,thereby paving the way for efficient synthesis of H2O2coupled with biomass valorization.

关键词： Free radical reactions

Unlocking the future:Mitochondrial genes and neural networks in predicting ovarian cancer prognosis and immunotherapy response

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World Journal of Clinical Oncology 2025年第1期16卷 43-52页

作者： Zhi-Jian Tang Yuan-Ming Pan wei Li Rui-Qiong Ma Jian-liu Wang Department of Obstetrics and Gynecology Peking University People’s HospitalBeijing 100044China Cancer Research Center Beijing Chest HospitalBeijing 101149China Department of Thoracic Surgery Sichuan Provincial People's HospitalChengdu 610072Sichuan ProvinceChina

BACKGROUND Mitochondrial genes are involved in tumor metabolism in ovarian cancer(OC)and affect immune cell infiltration and treatment *** To predict prognosis and immunotherapy response in patients diagnosed with OC using mitochondrial genes and neural *** Prognosis,immunotherapy efficacy,and next-generation sequencing data of patients with OC were downloaded from The Cancer Genome Atlas and Gene Expression *** genes were sourced from the MitoCarta3.0 *** discovery cohort for model construction was created from 70% of the patients,whereas the remaining 30% constituted the validation *** the expression of mitochondrial genes as the predictor variable and based on neural network algorithm,the overall survival time and immunotherapy efficacy(complete or partial response)of patients were *** In total,375 patients with OC were included to construct the prognostic model,and 26 patients were included to construct the immune efficacy *** average area under the receiver operating characteristic curve of the prognostic model was 0.7268[95% confidence interval(CI):0.7258-0.7278]in the discovery cohort and 0.6475(95%CI:0.6466-0.6484)in the validation *** average area under the receiver operating characteristic curve of the immunotherapy efficacy model was 0.9444(95%CI:0.8333-1.0000)in the discovery cohort and 0.9167(95%CI:0.6667-1.0000)in the validation *** The application of mitochondrial genes and neural networks has the potential to predict prognosis and immunotherapy response in patients with OC,providing valuable insights into personalized treatment strategies.

关键词： Ovarian cancer Mitochondria Prognosis Immunotherapy Neural network

影像学检查在乳腺导管内乳头状瘤诊断中的应用(附23例报告)

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苏州医学院学报 2001年第5期21卷 549-550页

作者：危少华刘根寿苏州大学附属第二医院普外科苏州215004

目的　总结影像学检查对乳腺导管内乳头状瘤的诊断价值。方法　回顾分析应用多功能超声、钼靶摄片及乳管造影对 2 3例乳腺导管内乳头瘤的检查结果。结果　多功能超声、乳管造影对乳腺导管内乳头瘤诊断的敏感性分别为 6 6 .7%和 70 .6 % ... 详细信息

目的　总结影像学检查对乳腺导管内乳头状瘤的诊断价值。方法　回顾分析应用多功能超声、钼靶摄片及乳管造影对 2 3例乳腺导管内乳头瘤的检查结果。结果　多功能超声、乳管造影对乳腺导管内乳头瘤诊断的敏感性分别为 6 6 .7%和 70 .6 % ,它们对本病均有较高的诊断价值。结论　影像学检查对乳腺导管内乳头状瘤病灶可作出定位诊断。

关键词：乳腺导管内乳头状瘤钼靶X线摄片乳管造影超声诊断乳腺肿瘤

Sodium fluoride sacrificing layer concept enables high-efficiency and stable methylammonium lead iodide perovskite solar cells

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Journal of Materials Science & Technology 2022年第18期113卷 138-146页

作者： Huimin Xiang Pengyun liu wei Wang Ran Ran wei Zhou Zongping shao College of Chemical Engineering State Key Laboratory of Materials-Oriented Chemical EngineeringNanjing Tech UniversityNanjing 210009China WA School of Mines:Minerals Energy and Chemical Engineering(WASM-MECE)Curtin UniversityPerthWA 6845Australia

As next-generation photovoltaic devices,methylammonium lead iodide(MAPbI_(3))-based organic-inorganic halide perovskite solar cells(PSCs)have received considerable attention because of their cost effectiveness and high ***,their practical applications are retarded due to severe instability under moisture,thermal and sunlight conditions,which are closely related to the insufficient perovskite film quality and high photocatalytic activity of defective TiO_(2) electron-transporting layer(ETL)to accelerate the perovskite ***,remarkably enhanced power conversion efficiency(PCE)and stability of MAPbI_(3)-based PSCs is reached through the use of a new sodium fluoride(NaF)sacrificing layer,which,introduced between the perovskite layer and ETL,is sacrificed during cell fabrication by penetrating into the perovskite layer,improving the perovskite film quality,while partial NaF is incorporated into the mesoporous TiO_(2) ETL during NaF layer fabrication to passivate TiO_(2) and construct a well-matched energy level *** a result,the optimized PSC generates a high PCE of 20.9%,which is 17%higher than that of the pristine cell(17.9%),and outstanding performance stability due to remarkably enhanced moisture,thermal and sunlight *** study highlights a simple and effective approach to boost the PCE and durability of MAPbI 3-based PSCs simultaneously,accelerating the commercialization of this technology.

关键词： Perovskite solar cells Sodium fluoride sacrificing layer Defect passivation Stability