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Nano Research 2024年第5期17卷 4517-4524页

作者： Jiwei Li yao xie Renrui Sun Junxun Zhou Lining Sun Department of Chemistry College of SciencesShanghai UniversityShanghai 200444China Department of Physics College of SciencesShanghai UniversityShanghai 200444China School of Medicine Shanghai UniversityShanghai 200444China

Luminescence quench is common in overdoped upconversion nanoparticles.Various methods have been proposed to counteract the adverse effects of concentration quenching on luminescence,but in upconversion nanoparticles that are highly doped with both sensitizers and activators,the factors that contribute to the diminishing of the emission cannot be summarized by a single cause.Herein,a core-shell design is used to spatially separate the sensitizer(Yb^(3+))and activator(Er^(3+))and to modulate the emission by changes in the distribution position as well as the concentration of the dopant ions in order to probe the factors affecting the luminescence.When the sensitizer ions are located in the core,the luminescence intensity of the nanoparticles is significantly weaker than that of the other distribution,which implies that the effect of sensitizer and activator on luminescence in the highly doped state has a different and more complex mechanism.The intensity of the emission is more affected by Yb^(3+)than Er^(3+),which includes not only the self-quenching of Yb^(3+),but also the dominance in the Yb^(3+)-Er^(3+)cross-relaxation.In this finding may provide new ideas for revealing the reasons for the diminished luminescence of highly doped upconversion nanoparticles and thus for enhancing luminescence.

关键词： upconversion luminescence lanthanide ion core-shell nanoparticles concentration quenching cross-relaxation

Cardiac Piezo1 Exacerbates Lethal Ventricular Arrhythmogenesis by Linking Mechanical Stress with Ca^(2+) Handling After Myocardial Infarction

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Research 2024年第1期2023卷 583-594页

作者： Sheng-an Su Yuhao Zhang Wudi Li Yutao Xi Yunrui Lu Jian Shen Yuankun Ma Yaping Wang Yimin Shen Lan xie Hong Ma yao xie Meixiang Xiang Department of Cardiology Cardiovascular Key Laboratory of Zhejiang ProvinceThe Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310009China Department of Endocrinology The Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310009China Texas Heart Institute HoustonTX 77030USA

Ventricular arrhythmogenesis is a key cause of sudden cardiac death following myocardial infarction(MI).Accumulating data show that ischemia,sympathetic activation,and inflammation contribute to arrhythmogenesis.However,the role and mechanisms of abnormal mechanical stress in ventricular arrhythmia following MI remain undefined.We aimed to examine the impact of increased mechanical stress and identify the role of the key sensor Piezo1 in ventricular arrhythmogenesis in MI.Concomitant with increased ventricular pressure,Piezo1,as a newly recognized mechano-sensitive cation channel,was the most up-regulated mechanosensor in the myocardium of patients with advanced heart failure.Piezo1 was mainly located at the intercalated discs and T-tubules of cardiomyocytes,which are responsible for intracellular calcium homeostasis and intercellular communication.

关键词： ventricular homeostasis Ventricular

Decarboxylative Amination with Nitroarenes via Synergistic Catalysis

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Chinese Journal of Chemistry 2024年第4期42卷 351-355页

作者： Meiling Ding Sitian Zhou Shunruo yao Chengjian Zhu Weipeng Li Jin xie State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsChemistry and Biomedicine Innovation Center(ChemBIC)School of Chemistry and Chemical EngineeringNanjing UniversityNanjingJiangsu210023 China Green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhouHenan450001 China

In this paper,we have developed a decarboxylative amination of carboxylic acids with nitroarenes for the synthesis of secondary amines.The protocol is performed at mild conditions without the use of noble metals as catalysts.A wide range of structurally diverse secondary amines could be obtained in good yields(up to 94%)with good functional group tolerance.This transformation shows good to excellent selectivity,avoiding the generation of over alkylated byproducts.

关键词： Nitroarenes Amines Synergistic catalysis Carboxylic acids Radical alkylation Amination Photocatalysis Steric hindrance

Dielectric metasurface evolution from bulk to monolayer by strong coupling of quasi-BICs for second harmonic boosting

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Photonics Research 2024年第4期12卷 784-792页

作者： YINONG xie QIANTING CHEN JIN yao XUEYING LIU ZHAOGANG DONG JINFENG ZHU Institute of Electromagnetics and Acoustics and Key Laboratory of Electromagnetic Wave Science and Detection Technology Xiamen UniversityXiamen 361005China Shenzhen Research Institute of Xiamen University Shenzhen 518057China Department of Electrical Engineering City University of Hong KongHong Kong 999077China Institute of Materials Research and Engineering(IMRE) Agency for ScienceTechnology and Research(A*STAR)Singapore 138634Singapore Department of Materials Science and Engineering National University of SingaporeSingapore 117575Singapore

2D materials are promising candidates as nonlinear optical components for on-chip devices due to their ultrathin structure. In general, their nonlinear optical responses are inherently weak due to the short interaction thickness with light. Recently, there has been great interest in using quasi-bound states in the continuum (q-BICs) of dielectric metasurfaces, which are able to achieve remarkable optical near-field enhancement for elevating the second harmonic generation (SHG) emission from 2D materials. However, most studies focus on the design of combining bulk dielectric metasurfaces with unpatterned 2D materials, which suffer considerable radiation loss and limit near-field enhancement by high-quality q-BIC resonances. Here, we investigate the dielectric metasurface evolution from bulk silicon to monolayer molybdenum disulfide (MoS2), and discover the critical role of meta-atom thickness design on enhancing near-field effects of two q-BIC modes. We further introduce the strongcoupling of the two q-BIC modes by oblique incidence manipulation, and enhance the localized optical field on monolayer MoS2dramatically. In the ultraviolet and visible regions, the MoS2SHG enhancement factor of our design is 105times higher than that of conventional bulk metasurfaces, leading to an extremely high nonlinear conversion efficiency of 5.8%. Our research will provide an important theoretical guide for the design of high-performance nonlinear devices based on 2D materials.

关键词： monolayer harmonic quasi

Combining graph neural network with deep reinforcement learning for resource allocation in computing force networks

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Frontiers of Information Technology & Electronic Engineering 2024年第5期25卷 701-712页

作者： Xueying HAN Mingxi xie Ke YU Xiaohong HUANG Zongpeng DU Huijuan yao School of Computer Science Beijing University of Posts and TelecommunicationsBeijing 100876China School of Artificial Intelligence Beijing University of Posts and TelecommunicationsBeijing 100876China Department of Infrastructure Network Technology Research China Mobile Research InstituteBeijing 100032China

Fueled by the explosive growth of ultra-low-latency and real-time applications with specific computing and network performance requirements,the computing force network(CFN)has become a hot research subject.The primary CFN challenge is to leverage network resources and computing resources.Although recent advances in deep reinforcement learning(DRL)have brought significant improvement in network optimization,these methods still suffer from topology changes and fail to generalize for those topologies not seen in training.This paper proposes a graph neural network(GNN)based DRL framework to accommodate network trafic and computing resources jointly and efficiently.By taking advantage of the generalization capability in GNN,the proposed method can operate over variable topologies and obtain higher performance than the other DRL methods.

关键词： Computing force network Routing optimization Deep learning Graph neural network Resource allocation

A novel mutation of glycogen synthase kinase-3β leads to a reduced level of GSK3βprotein in a patient with dilated cardiomyopathy

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Genes & Diseases 2024年第1期11卷 84-86页

作者： Ke Gong Zhiping Tan Haidan Liu Xiaobo Liao Xinmin Zhou Bangliang Yin Shi Zeng yao yao Yifeng Yang Li xie Department of Cardiovascular Surgery The Second Xiangya Hospital of Central South UniversityCentral South UniversityChangshaHunan410011China Department of Ultrasound The Second Xiangya Hospital of Central South UniversityCentral South UniversityChangshaHunan 410011China Department of Blood Transfusion The Second Xiangya Hospital of Central South UniversityCentral South UniversityChangshaHunan 410011China

Dilated cardiomyopathy(DCM)is a frequently inherited heart condition.A familial transmission rate of 20%-35%has been documented,and most of these cases are autosomal dominant.This condition has a high rate of morbidit... 详细信息

关键词： GSK3β cardiomyopathy mortality

Experimental and numerical study on protective effect of RC blast wall against air shock wave

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Defence Technology（防务技术） 2024年第1期31卷 567-579页

作者： Xin-zhe Nian Quan-min xie Xin-li Kong Ying-kang yao Kui Huang State Key Laboratory of Precision Blasting Jianghan UniversityWuhan430056China Hubei Key Laboratory of Blasting Engineering Jianghan UniversityWuhan430056China Hubei(Wuhan)Institute of Explosion and Blasting Technology Jianghan UniversityWuhan430056China College of Defense Engineering Army Engineering University of PLANanjing210007China Institute of Defense Engineering AMSPLALuoyang471023China

Prototype experiments were carried out on the explosion-proof performance of the RC blast wall.The mass of TNT detonated in the experiments is 5 kg and 20 kg respectively.The shock wave overpressure was tested in different regions.The above experiments were numerically simulated,and the simulated shock wave overpressure waveforms were compared with that tested and given by CONWEP program.The results show that the numerically simulated waveform is slightly different from the test waveform,but similar to CONWEP waveform.Through dimensional analysis and numerical simulation under different working conditions,the equation for the attenuation rate of the diffraction overpressure behind the blast wall was obtained.According to the corresponding standards,the degree of casualties and the damage degree of the brick concrete building at a certain distance behind the wall can be determined when parameters are set.The above results can provide a reference for the design and construction of the reinforced concrete blast wall.

关键词： Blast wall Shock wave Diffraction Overpressure Protection

Alignment error modeling and control of a double-sided microlens array during precision glass molding

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Microsystems & Nanoengineering 2024年第2期10卷 311-322页

作者： Zihao Zeng Tianfeng Zhou Qian Yu Jia Zhou Gang Wang Qiuchen xie Zifan Wang Xiaoqiang yao Yubing Guo School of Medical Technology Beijing Institute of TechnologyNo.5 Zhongguancun South StreetHaidian DistrictBeijing100081China School of Mechanical Engineering Beijing Institute of TechnologyNo.5 Zhongguancun South StreetHaidian DistrictBeijing100081China

Double-sided microlens arrays(DSMLAs)include combinations of two single-sided MLAs to overcome positioning errors and greatly improve light transmissivity compared to other types of lenses.Precision glass molding(PGM)is used to fabricate DSMLAs,but controlling alignment errors during this process is challenging.In this paper,a mold assembly was manufactured with a novel combination of materials to improve the alignment accuracy of mold cores during PGM by using the nonlinear thermal expansion characteristics of the various materials to improve the DSMLA alignment accuracy.By establishing a mathematical model of the DSMLA alignment error and a thermal expansion model of the mold-sleeve pair,the relationship between the maximum alignment error of the DSMLA and the mold-sleeve gap was determined.This research provides a method to optimize the mold-sleeve gap and minimize the alignment error of the DSMLA.The measured DSMLA alignment error was 10.56μm,which is similar to the predicted maximum alignment error.Optical measurements showed that the uniformity of the homogenized beam spot was 97.81%,and the effective homogeneous area accounted for 91.66%of the total area.This proposed method provides a novel strategy to improve the performance of DSMLAs.

关键词： sided alignment error

The endogenous antioxidant ability of royal jelly in Drosophila is independent of Keap1/Nrf2 by activating oxidoreductase activity

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Insect Science 2024年第2期31卷 503-523页

作者： Dongjing Wen Jiayu xie yao Yuan Lirong Shen Yufeng Yang Wenfeng Chen Institute of Life Sciences College of Biological Science and EngineeringFuzhou UniversityFuzhouChina School of Medicine Chongqing UniversityChongqingChina College of Biosystems Engineering and Food Science Zhejiang UniversityHangzhouChina

Royal jelly(RJ)is a biologically active substance secreted by the hypopharyngeal and mandibular glands of worker honeybees.It is widely claimed that RJ reduces oxidative stress.However,the antioxidant activity of RJ has mostly been determined by in vitro chemical detection methods or by external administration drugs that cause oxidative stress.Whether RJ can clear the endogenous production of reactive oxygen species(ROS)in cells remains largely unknown.Here,we systematically investigated the antioxidant properties of RJ using several endogenous oxidative stress models of Drosophila.We found that RJ enhanced sleep quality of aging Drosophila,which is decreased due to an increase of oxidative damage with age.RJ supplementation improved survival and suppressed ROS levels in gut cells of flies upon exposure to hydrogen peroxide or to the neurotoxic agent paraquat.Moreover,RJ supplementation moderated levels of ROS in endogenous gut cells and extended lifespan after exposure of flies to heat stress.Sleep deprivation leads to accumulation of ROS in the gut cells,and RJ attenuated the consequences of oxidative stress caused by sleep loss and prolonged lifespan.Mechanistically,RJ prevented cell oxidative damage caused by heat stress or sleep deprivation,with the antioxidant activity in vivo independent of Keap1/Nrf2 signaling.RJ supplementation activated oxidoreductase activity in the guts of flies,suggesting its ability to inhibit endogenous oxidative stress and maintain health,possibly in humans.

关键词： antioxidant biological oxidations Drosophila oxidative stress royal jelly sleep loss

The synthesis of fluorescent nanoclusters based on the etching reaction

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Nano Research 2024年第5期17卷 4631-4638页

作者： Hongbin Lin Yitao Cao Qiaofeng yao Tiankai Chen Huiting Shan Jianping xie Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou 350207China Department of Chemical and Biomolecular Engineering National University of SingaporeSingapore 117585Singapore National and Local Joint Engineering Research Center of MPTES in High Energy and Safety LIBs Engineering Research Center of MTEES(Ministry of Education)and Key Laboratory of ETESPG(GHEI)South China Normal UniversityGuangzhou 510006China Tianjin Key Laboratory of Molecular Optoelectronic Sciences Key Laboratory of Integrated Organic CircuitsMinistry of EducationDepartment of ChemistrySchool of ScienceTianjin UniversityTianjin 300072China

Thiolate-protected atomically precise nanoclusters(NCs)demonstrate a series of unique luminescent characteristics attributed to their various peculiar electronic structures.Therefore,fluorescent NCs present extraordinary practical values in biosensing and bioimaging research fields.Nevertheless,restricted by the types of fluorescent NCs,there are great difficulties in promoting the development of NCs in fluorescent research areas.As a result,it is of significant necessity for researchers to develop new synthetic pathways to produce high-quality fluorescent NCs.According to the analysis about the structural characteristics of fluorescent NCs,some general features like longer motif and higher ligand-to-metal ratio can be found,consistent to some presented regularities in etching reaction.Consequently,in this work,we used Au_(25)(MHA)_(18)(MHA=6-mercaptohexanoic acid)as a model nanocluster and utilized the etching reaction to systematically explore etching products and their corresponding luminescent properties.Moreover,we also identified three main reaction processes in the entire etching reaction process,which can generate new metal nanocluster species with various fluorescent properties.Hence,the etching reaction will provide a good platform to produce new luminescent metal NC species.

关键词： etching reaction metal nanoclusters fluorescent properties fluorescent conversion