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Secure beamforming and deployment design for rate-splitting multiple access-based UAV communications

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Science China(Information Sciences) 2025年第1期68卷 342-356页

作者： Bing WANG Xiaofeng TAO Shujun han Huici WU Kai YANG zhu han National Engineering Research Center of Mobile Network Technologies Beijing University of Posts and Telecommunications Peng Cheng Laboratory Department of Electrical and Computer Engineering University of Houston

Rate-splitting multiple access(RSMA) has recently gained attention as a potential robust multiple access(MA)scheme for upcoming wireless networks. Given its ability to efficiently utilize wireless resources and design interference management strategies, it can be applied to unmanned aerial vehicle(UAV) networks to provide convenient services for large-scale access ground users. However, due to the line-of-sight(LoS) broadcast nature of UAV transmission, information is susceptible to eavesdropping in RSMA-based UAV networks. Moreover, the superposition of signals at the receiver in such networks becomes complicated. To cope with the challenge, we propose a two-user multi-input single-output(MISO) RSMA-based UAV secure transmission framework in downlink communication networks. In a passive eavesdropping scenario, our goal is to maximize the sum secrecy rate by optimizing the transmit beamforming and deployment location of the UAV-base station(UAV-BS),while considering quality-of-service(QoS) constraints, maximum transmit power, and flight space limitations. To address the non-convexity of the proposed problem, the optimization problem is first decoupled into two subproblems. Then, the successive convex approximation(SCA) method is employed to solve each subproblem using different propositions. In addition, an alternating optimization(AO)-based location RSMA(L-RSMA) beamforming algorithm is developed to implement joint optimization to obtain the suboptimal solution. Numerical results demonstrate that(1) the proposed L-RSMA scheme yields a28.97% higher sum secrecy rate than the baseline L-space division multiple access(SDMA) scheme;(2) the proposed L-RSMA scheme improves the security performance by 42.61% compared to the L-non-orthogonal multiple access(NOMA) scheme.

关键词： rate-splitting multiple access UAV communication precoding optimization deployment location physical layer security

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The MING proposal at SHINE:megahertz cavity enhanced X‑ray generation

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Nuclear Science and Techniques 2023年第1期34卷 51-85页

作者： Nan‑Shun Huang zi‑Peng Liu Bang‑Jie Deng zi‑han zhu Shao‑Hua Li Tao Liu Zheng Qi Jia‑Wei Yan Wei Zhang Sheng‑Wang Xiang Yang‑Yang Lei Ya zhu Yong‑Zhou He Qi‑Bing Yuan Fei Gao Rong‑Bing Deng Sen Sun Zhi‑Di Lei Zhi‑Qiang Jiang Meng‑Qi Duan Yuan zhuan Xue‑Fang Huang Peng‑Cheng Dong Zhong‑Liang Li Shang‑Yu Si Lian Xue Si Chen Yong‑Fang Liu Ya‑Jun Tong Hai‑Xiao Deng Zhen‑Tang Zhao Zhangjiang Laboratory Shanghai 201210China School of Nuclear Science and Technology Xi’an Jiaotong UniversityXi’an 710049ShaanxiChina Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China European XFEL Schenefeld 22869Germany ShanghaiTech University Shanghai 201210China

The cavity-based X-ray free-electron laser(XFEL)has promise in producing fully coherent pulses with a bandwidth of a few meV and very stable intensity,whereas the currently existing self-amplified spontaneous emission(SASE)XFEL is capable of generating ultra-short pulses with chaotic *** general,a cavity-based XFEL can provide a spectral brightness three orders of magnitude higher than that of the SASE mode,thereby opening a new door for cutting-edge scientific *** the development of superconducting MHz repetition-rate XFEL facilities such as FLASH,European-XFEL,LCLS-II,and SHINE,practical cavity-based XFEL operations are becoming increasingly *** this study,megahertz cavity enhanced X-ray generation(MING)is proposed based on China’s first hard XFEL facility-SHINE,which we refer to as MING@SHINE.

关键词： X-ray free-electron laser Free electron laser oscillator Fully coherent X-ray

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Combination of fruquintinib with venetoclax for the treatment of colorectal cancer

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Oncology Research 2025年第1期33卷 225-234页

作者： WEI ZhanG WEICHENG WANG RUI WANG XIAO han LIJUN zhu WENJIE GUO YANHONG GU Department of Oncology The First Affiliated Hospital of Nanjing Medical UniversityNanjing210029China State Key Laboratory of Pharmaceutical Biotechnology School of Life SciencesNanjing UniversityNanjing210023China Department of Oncology The Affiliated Taizhou People’s Hospital of Nanjing Medical UniversityTaizhou225300China

Background:As a novel blocker of vascular endothelial growth factor receptor(VEGFR),fruquintinib has been approved for treating colorectal cancer(CRC).However,its dosage and therapeutic efficacy are limited by its widespread adverse ***,recognized as the initial inhibitor of B-cell lymphoma protein 2(BCL2),has shown potential in boosting the effectiveness of immunotherapy against *** study investigated the efficacy and mechanisms of fruquintinib combined with venetoclax in treating *** and Materials:We developed a colon cancer mouse model with the CT26 colon cell line to demonstrate fruquintinib and venetoclax’s efficacy against *** we employed various techniques to evaluate different aspects of the experimental *** was used to detect cell proliferation and angiogenesis in tumor *** blot analysis was utilized to examine the occurrence of cell apoptosis,and flow cytometry to quantitate immune cells within the tumor ***,immunofluorescence was employed to measure cytokine ***:The strongest inhibition on tumor growth was achieved by the combination of fruquintinib with venetoclax,as opposed to individual drug *** was found to amplify the impact of fruquintinib,leading to decreased cancer cell proliferation,increased cancer cell apoptosis,lowered angiogenesis,better vascular structure normalization,and improved immune cell ***:Our findings indicate that the addition of venetoclax enhances the impact of fruquintinib on vascular normalization and modulation of the tumor immune *** study presents the justification for utilizing the fruquintinib and venetoclax combination in treating *** holds promise in being assimilated into anticancer medications for CRC.

关键词： Colorectal cancer(CRC) B-cell lymphoma protein 2(BCL2) Venetoclax Vascular endothelial growth factor receptor(VEGFR) Fruquintinib Anti-angiogenesis Immunotherapy

Trinuclear gold-catalyzed site-selective alkylation of peptides

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Science China Chemistry 2025年第1期68卷 249-256页

作者： Qing-Yun Fang Chengyihan Gu Yinghan Chen Wencheng Yan Yong Liang Weipeng Li Chengjian zhu Jie han Jin Xie State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic Materials Chemistry and Biomedicine Innovation Center (Chem BIC) School of Chemistry and Chemical Engineering Nanjing University Green Catalysis Center College of Chemistry Zhengzhou University State Key Laboratory of Natural Medicines China Pharmaceutical University

Selective modification of peptides has always been a challenging issue. The selective alkylation of peptides can alter the biological activity and physical properties of molecules, and it has gained significant research interest. We herein disclose an intriguing gold-catalyzed alkylation of peptides using bench-stable unactivated alkyl bromides under photoredox catalysis. A wide range of structurally diverse primary, secondary and tertiary alkyl bromides serve as effective coupling partners to precisely connect with the α-C(sp3)–H in glycine residue of peptides. This protocol demonstrates an exceptionally broad scope for alkyl halides and excellent tolerance for a wide range of useful functional groups. A series of relay transformations to construct cyclic peptides, to proceed click reaction and to realize peptide fluorescence labeling further enhance its synthetic practicality. In addition, mechanistic studies and density functional theory(DFT) calculations reveal an inner-sphere and subsequent outersphere single electron transfer(SET) mechanism.

关键词： gold catalysis peptide alkylation C-C coupling radical

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Tuning the porosity of {Co12IICo8III（μ3-OH）24（X）}11+ supramolecular frameworks by reaction time for D2/H2 separation

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Science China Chemistry 2025年

作者： zhuozhou Xie zhu zhuo zi-Ang Nan Qing Li Xiufang Li zi-Xiu Lu Linzhe Lü Jin Liu Luyao Liu Wenjing Wang Wei Wang Daqiang Yuan You-Gui Huang State Key Laboratory of Structure Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences University of Chinese Academy of Sciences Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth Materials Haixi InstitutesChinese Academy of Sciences State Key Laboratory of Physical Chemistry of Solid Surfaces Department of Chemistry College of Chemistry and Chemical EngineeringXiamen University

Systematicly tuning the porosities of porous materials is crucial for targeted gas mixture separation,yet it remains a longstanding *** a common strategy,altering the phenylene ring count in the organic building units has been exploited to adjust pore apertures in metal organic frameworks （MOFs） and covalent organic frameworks （COFs）,resulting in only a stepwise pore size variation of approximately 2.8?.Unlike MOFs and COFs,the porosities for supramolecular assembly frameworks are highly dependent on the packings of the molecular building units in the *** above strategy cannot be applied to supramolecular assembly frameworks and other strategies are required to adjust pore apertures in supramolecular frameworks,especially to achieve porous materials with the optimal pore size for D2/H2separation （～3?）.Here,we successfully modulate the porosity of supramolecular frameworks of[CoII1+12CoIII8L12（μ3-OH）24（X）]1clusters （L=mono-deprotonated 1-iminoisoindole-3-amine,X=ClO?4or Cl?） by controlling the duration of self-assembly *** simply adjusting the reaction time,we obtain three[CoII12CoIII8L12（μ3-OH）24（X）]11+supramolecular frameworks:[CoII12CoIII8（μ3-OH）24（ClO4）L12)]·（Cl）4·（HCO2）7（1）,[CoII12CoIII8L12（μ3-OH）24（Cl）]·（ClOI4）4·（Cl）6·（HCO2）·（H2O）10（2）,and[CoI12CoIII8L12（μ3-OH）24（Cl）]·（Cl）11·（H2O）12（3）.The different stacking patterns of the[CoII12CoIII8L12（μ3-OH）24（X）]11+clusters in these frameworks lead to significantly varied stabilities and *** 1 exhibits permanent porosity with interconnected channels and maintains stability under harsh *** contrast,compound 2 is nearly nonporous,and compound 3 becomes unstable upon *** pores of compound 1 show higher affinity to D2than H2,and the pore aperture diameter of compound 1 （～3.06?） meets the optimal porosity for D2/***,compound 1 demonstrates moderate D2/H2separation at 77 K (retention time:～7 min/g for D2/H2/Ne （10/10/80 vol%） in a flow of 5 mL

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Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2025年第1期68卷 288-296页

作者： Shuai Liu Wen-Qiang Xu Ying-Tong Di Man-Cheng Tang Ding-Kang Chen Ming-Ming Cao Yao-Wen Chang Hong-Yu Tang Chun-Mao Yuan Jun-Bo Yang Zhi-Li Zuo han Guo zi-Fei Xu Ying Zeng Yun-Dong Wu Xiao-Jiang Hao Key Laboratory of Phytochemistry and Natural Medicines (Chinese Academy of Sciences) Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen Bay Laboratory State Key Laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

关键词： metabolon Diels-Alder reaction semipinacol rearrangement biosynthesis notoamides spiro polycyclic alkaloids

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新乡市近65a降水和干旱变化特征分析

甘肃农业大学学报 2017年第4期52卷 158-163页

作者：甄小丽孙海燕袁鸿猷字寒竹刘艳伟内蒙古建筑职业技术学院内蒙古呼和浩特010070 内蒙古机电职业技术学院内蒙古呼和浩特010070 昆明理工大学现代农业工程学院云南昆明650500

【目的】掌握新乡市近65a(1951-2015)的降水和干旱特征,旨在为新乡地区农业提供干旱预警.【方法】采用标准化降水指数(standardized precipitation index,SPI)对新乡市近65a的干旱状况进行计算,采用线性倾向法对降水和干旱进行趋势分析... 详细信息

【目的】掌握新乡市近65a(1951-2015)的降水和干旱特征,旨在为新乡地区农业提供干旱预警.【方法】采用标准化降水指数(standardized precipitation index,SPI)对新乡市近65a的干旱状况进行计算,采用线性倾向法对降水和干旱进行趋势分析,采用滑动t检验法对其突变情况进行分析.【结果】新乡市春、夏和冬季降水呈现逐渐下降的趋势,气候倾向率分别为-16.9、-17.3和-0.15mm/10a;年、春季和夏季降水在1977、1982和1977年发生突变,突变前后平均值变化率分别为-14.5%、16.6%和21.0%;年SPI12呈现微弱下降的趋势,气候倾向率为-0.10/10a,全年和四季干旱均有增加趋势.年SPI_(12)无突变,春季、秋季和冬季SPI12发生突变的年份分别是1978、1977、1978年.【结论】近65a来新乡市降水量有下降的趋势,旱情日益严重.

关键词：新乡市降水干旱标准化降水指数滑动t检验突变

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A robust statistical prediction model for late-summer heavy precipitation days in North China

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Science China Earth Sciences 2025年第1期68卷 158-171页

作者： Shunli JIANG Tingting han Xin ZHOU Huijun WANG Zhicong YIN Xiaolei SONG Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disaster Ministry of Education Nanjing University for Information Science and Technology Nansen-zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Southern Marine Science and Engineering Guangdong Laboratory (zhuhai)

Recently, heavy precipitation(HP) events have occurred frequently in North China(NC), causing devastating economic losses and human fatalities. However, the short-term climate prediction of HP is quite limited. Combining year-to-year increment(DY) method and sliding correlations, we developed a robust seasonal prediction model for late-summer HP days(HPDs) in NC during 1982–2022, utilizing three independent predictors—February sea surface temperature(SST) in the Indian Ocean(SST＿IO), February snow depth over North Asia(SDE＿NA), and May melted snow depth in NC(MSDE＿NC). The SST＿IO anomalies affect NC's precipitation through the Pacific-Japan pattern. The SDE＿NA anomalies are associated with East Asian anomalous anticyclone by southeastern propagation of Rossby wave at Eurasia. The MSDE＿NC anomalies are followed by vertical motion and moisture anomalies in situ and thereby cause precipitation anomalies. This prediction model can well simulate the variations of the HPDs, with a correlation coefficient(CC) of 0.81(0.65) between the observed and predicted HPDs＿DY(HPDs＿anomaly). The percentage with the same sign for 15 extreme HPDs＿anomaly years(PSSE) is 100%.Moreover, in the cross-validation test during 1982–2022, the PSSE for HPDs＿anomaly is as high as 100%, along with a low rootmean-square error of 1.14. For independent hindcasts during 2013–2022, the CC between the observed and predicted HPDs＿DY(HPDs＿anomaly) is 0.93(0.83), together with high Nash-Sutcliffe efficiency(0.82) and agreement index(0.89). Specifically, the predictions are broadly consistent with the observations for 2015, 2016, 2017, 2021, and 2022, reflecting excellent performance of this prediction model of HPDs in NC.

关键词： Heavy precipitation at North China Year-to-year increment approach Robust seasonal prediction Sea surface temperature Snow depth

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Plasmon-induced local electric field improved hydrogen evolution reaction on Ag/Mo_(2)C nanosheets

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Nano Research 2025年第1期18卷 270-277页

作者： HuangJingWei Li Xin zi Jun Wu Xinli Wang Li zhu Qiyou Wang Jianfu han Junwei Fu Hongmei Li Kai Huang Yu Chen Min Liu School of Physics State Key Laboratory of Powder MetallurgyHunan Joint International Research Center for Carbon Dioxide Resource UtilizationCentral South UniversityChangsha 410083China School of Metallurgy and Environment Central South UniversityChangsha 410083China Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Nano-Institute Munich Faculty of PhysicsLudwig-Maxilimians-Universität MünchenMünchen 80539Germany Hunan Institute of Advanced Sensing and Information Technology Xiangtan UniversityXiangtan 411105China

Electrocatalytic water splitting offers a promising way for hydrogen production with near-zero ***,such as molybdenum carbides(Mo_(2)C),are promising materials for hydrogen evolution reaction(HER)but still suffer from poor intrinsic water activation ***,we developed a plasmon-induced local electric field(PILEF)strategy to solve this ***(Ag)nanoparticles decorated Mo_(2)C nanosheets(Ag/Mo_(2)C)were successfully prepared by electrostatic *** visible light excited the PILEF on Ag/Mo_(2)C remarkably reducing the activation energy by 92.7 kJ·mol^(-1)from 147.3 kJ·mol^(-1)of Mo_(2)C to 54.6 kJ·mol^(-1).As a result,the plasmonic Ag/Mo_(2)C significantly enhances~2.3-fold of the current density from 2.8 mA·cm^(-2)of Mo_(2)C to 6.5 mA·cm^(-2)at-3 V *** and reduces the overpotential by 104 mV from 403 mV of dark state to 299 mV of light state at the current density of 10 mA·cm^(-2),achieving better performance than reported *** research demonstrates that PILEF enhances HER activities,offering a potential strategy for boosting the intrinsic activities of catalysts.

关键词： sliver particles plasmon effect field effect hydrogen evolution reaction(HER) electrocatalysis