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Chinese Journal of Chemistry 2022年第19期40卷 2305-2312页

作者： Yang Zhou Yangkang Fu Mao Chen Department of Macromolecular Science State Key Laboratory of Molecular Engineering of PolymersFudan UniversityShanghai200438 China

Molecular weight distribution(MWD)is fundamental for polymer analysis,which influences many important properties of polymeric materials.In this work,we demonstrate the development of a computer-aided droplet-flow system that combines photo-mediated reversible-deactivation radical polymerization(RDRP)and chain transfer agent(CTA)diffusion strategy to enable facile MWD control for the first time.Synthetic advantages of this photo-flow polymerization allow controlled chain-growth to yield a variety of polymers of tunable MWDs in a broad range(Ð≈1.1—1.9)with predetermined molecular weights(Mn≈4—30 kDa)and good chain-end fidelity.Notably,the computer-aided platform has streamlined an automatic and high-throughput pathway to prepare polymer libraries of tunable MWDs.For copolymers,chemical compositions could be readily regulated besides MWDs with the droplet-flow platform.We believe that this work should be attractive for polymer engineering,and informative to create more flow polymerization techniques toward on-demand control of diverse polymer characters.

关键词： Photocatalysis Copolymerization Synthetic methods Molecular weight distribution Flow chemistry

Evaluation of systemic impact of tricuspid regurgitation:an appeal for the notion of tricuspid regurgitation syndrome

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Chinese Medical Journal 2023年第2期136卷 138-140页

作者： Fanglin Lu Tianyuan Xiong Mao Chen Department of Cardiovascular Surgery Changhai HospitalSecond Military Medical UniversityShanghai 200433China Department of Cardiology West China HospitalSichuan UniversityChengduSichuan 610041China

Tricuspid regurgitation(TR)is an often encountered but undertreated valvular heart lesion.Unlike left-sided valvular diseases,it is estimated that only 5%of patients with significant TR were treated surgically,among which 86%were treated in combination with other major procedures.[1]This unmet need partially resulted from the lack of prospective evidence on reduced mortality of severe TR benefiting from surgery,alongside a historical viewpoint that functional TR(being the etiology for the vast majority of TR)would be improved once problems in the left heart are corrected.However,untreated severe TR shows various symptoms and a poor prognosis,including increased early and late mortality and impaired quality of life.[2]With the rapid development of catheter-based valve therapies,less invasive treatment options have been offered to the once forgotten tricuspid valve,further expanding the complexity of decision-making for TR intervention.

关键词： mortality regurgitation impaired

Computer-Aided Living Polymerization Conducted under Continuous-Flow Conditions

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Chinese Journal of Chemistry 2022年第2期40卷 285-296页

作者： Zeyu Wang Yang Zhou Mao Chen State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200438China

Continuous-flow techniques have promoted the development of synthetic chemistry due to advantages such as outstanding mass/heat transfer,on-demand scalability,improved safety,precise regulation on reaction parameters,etc.Recently,the combination of flow polymerization with computer scienee has gained considerable interests,leading to a variety of cutting-edge synthetic techniques.This review summarizes emerging achievements realized via the integration of computer science and living flow polymerizations,including 1)high-throughput living polymerizations in flow,2)programmable regulations of dispersity profile,se-que nee and topology for polymers,3)modular desig n with on line mon itori ng,as well as 4)self-optimized living polymerizati ons in flow.We expect that this summary will furnish informative kno wledge to scie ntists in related directions and in spire new ideas to further empower on-demand polymer engineering with modern techniques.

关键词： Polymers Synthetic methods Polymerization Flow chemistry Computer-aided synthesis

Equilibrium Strategy of the Pursuit-Evasion Game in Three-Dimensional Space

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 446-458页

作者： Nuo chen Linjing Li Wenji mao School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049 Institute of Automation Chinese Academy of SciencesBeijing 100190China

The pursuit-evasion game models the strategic interaction among players, attracting attention in many realistic scenarios, such as missile guidance, unmanned aerial vehicles, and target defense. Existing studies mainly concentrate on the cooperative pursuit of multiple players in two-dimensional pursuit-evasion games. However, these approaches can hardly be applied to practical situations where players usually move in three-dimensional space with a three-degree-of-freedom control. In this paper,we make the first attempt to investigate the equilibrium strategy of the realistic pursuit-evasion game, in which the pursuer follows a three-degree-of-freedom control, and the evader moves freely. First, we describe the pursuer's three-degree-of-freedom control and the evader's relative coordinate. We then rigorously derive the equilibrium strategy by solving the retrogressive path equation according to the Hamilton-Jacobi-Bellman-Isaacs(HJBI) method, which divides the pursuit-evasion process into the navigation and acceleration phases. Besides, we analyze the maximum allowable speed for the pursuer to capture the evader successfully and provide the strategy with which the evader can escape when the pursuer's speed exceeds the threshold. We further conduct comparison tests with various unilateral deviations to verify that the proposed strategy forms a Nash equilibrium.

关键词： Differential game equilibrium strategy pursuit-evasion game threedegree-of-freedom control

Simulation and experimental improvement on a small-scale Stirling thermo-acoustic engine

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Frontiers in Energy 2016年第1期10卷 37-45页

作者： Mao Chen Yonglin JU Institute of Refrigeration and Cryogenics Shanghai Jiao TongUniversity Shanghai 200240 China

Compared with the traditional engines, the thermo-acoustic engines are relatively new and can act as the linear compressors for refrigerators. Many institutes have shown great interest in this kind of machine for its absence of moving mechanical part. In this paper, the influence of the dimensions of the main parts of the small- scale Stifling thermo-acoustic engine was numerically simulated using a computer code called DeltaEC. The resonator and the resonator cavity were found to be the most convenient and effective in improving the perfor- mance of the engine. Based on the numerical simulation, a small-scale Stifling thermo-acoustic engine were constructed and experimentally investigated. Currently, with a resonator length of only 1 m, the working frequency of the engine was decreased to 90 Hz and the onset temperature difference was decreased to 198.2 K.

关键词： thermo-acoustic Stifling engine small-scale simulation experiment

An update on placental drug transport and its relevance to fetal drug exposure

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Medical Review 2022年第5期2卷 501-511页

作者： Qingcheng mao Xin chen Department of Pharmaceutics School of PharmacyUniversity of WashingtonBox 357610 H272F Health Science Building 1959 NE Pacific StreetSeattleWashington 98195USA Department of Pharmaceutics School of PharmacyUniversity of WashingtonSeattleWashingtonUSA

Pregnant women are often complicated with diseases that require treatment with medication.Most drugs administered to pregnant women are off-label without the necessary dose,efficacy,and safety information.Knowledge concerning drug transfer across the placental barrier is essential for understanding fetal drug exposure and hence drug safety and efficacy to the fetus.Transporters expressed in the placenta,including adenosine triphosphate(ATP)-binding cassette efflux transporters and solute carrier uptake transporters,play important roles in determining drug transfer across the placental barrier,leading to fetal exposure to the drugs.In this review,we provide an update on placental drug transport,including in vitro cell/tissue,ex vivo human placenta perfusion,and in vivo animal studies that can be used to determine the expression and function of drug transporters in the placenta as well as placental drug transfer and fetal drug exposure.We also describe how the knowledge of placental drug transfer through passive diffusion or active transport can be combined with physiologically based pharmacokinetic modeling and simulation to predict systemic fetal drug exposure.Finally,we highlight knowledge gaps in studying placental drug transport and predicting fetal drug exposure and discuss future research directions to fill these gaps.

关键词： adenosine triphosphate-binding cassette transporters fetal drug exposure physiologically based pharmacokinetic modeling and simulation placental drug transport solute carrier transporters.

Porous polymeric ligand promoted copper-catalyzed C-N coupling of(hetero)aryl chlorides under visible-light irradiation

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Science China Chemistry 2021年第1期64卷 17-21页

作者： Erfei Wang Kaixuan chen Yinan chen Jiawei Zhang Xinrong Lin Mao Chen State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200438China Key Laboratory of Medicinal Chemistry for Natural Resource Ministry of Education and Yunnan ProvinceSchool of Chemical Science and TechnologyYunnan UniversityKunming 650091China

A porous polymeric ligand(PPL)has been synthesized and complexed with copper to generate a heterogeneous catalyst(Cu@PPL)that has facilitated the efficient C-N coupling with various(hetero)aryl chlorides under mild conditions of visiblelight irradiation at 80°C(58 examples,up to 99%yields).This method could be applied to both aqueous ammonia and substituted amines,and is compatible to a variety of functional groups and heterocycles,as well as allows tandem C-N couplings with conjunctive dihalides.Furthermore,the heterogeneous characteristic of Cu@PPL has enabled a straightforward catalyst separation in multiple times of recycling with negligible catalytic efficiency loss by simple filtration,affording reaction mixtures containing less than 1 ppm of Cu residue.

关键词： polymeric catalyst heterogeneous catalysis photocatalysis C-N coupling

Single image defogging via multi-exposure image fusion and detail enhancement

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Journal of Safety Science and Resilience 2024年第1期5卷 37-46页

作者： Wenjing mao Dezhi Zheng Minze chen Juqiang chen School of Information and Electronics Advanced Research Institute of Multidisciplinary ScienceBeijing Institute of TechnologyBeijing100081China Chinese Aeronautical Establishment Beijing100012China

Outdoor cameras play an important role in monitoring security and social governance.As a common weather phenomenon,haze can easily affect the quality of camera shooting,resulting in loss and distortion of image details.This paper proposes an improved multi-exposure image fusion defogging technique based on the artificial multi-exposure image fusion(AMEF)algorithm.First,the foggy image is adaptively exposed,and the fused image is subsequently obtained via multiple exposures.The fusion weight is determined by the saturation,contrast,and brightness.Finally,the image fused by a multi-scale Laplacian algorithm is enhanced with simple adaptive details to obtain a clearer defogging image.It is subjectively and objectively verified that this algorithm can obtain more image details and distinct picture colors without a priori information,effectively improving the defogging ability.

关键词： Image defogging Multi-scale fusion Laplacian pyramid Adaptive detail enhancement

IDDoR:a novel reporter mouse system for simultaneous and quantitative in vivo analysis of both DNA double-strand break repair pathways

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Protein & Cell 2023年第5期14卷 369-375页

作者： Yu chen Zhen Cui Zhixi chen Ying Jiang Zhiyong mao Shanghai Key Laboratory of Maternal Fetal Medicine Clinical and Translational Research Center of Shanghai First Maternity and Infant HospitalFrontier Science Center for Stem Cell ResearchSchool of Life Sciences and TechnologyTongji UniversityShanghai 200092China Tsingtao Advanced Research Institute Tongji UniversityQingdao 266071China State Key Laboratory of Natural Medicines China Pharmaceutical UniversityNanjing 210009China

Dear Editor,Two distinct pathways,non-homologous end joining(NHEJ)and homologous recombination(HR)repair,have evolved to repair DNA double-strand breaks(DSBs),the most deleterious type of DNA damage.Impaired NHEJ and HR are often associated with a high incidence of tumorigenesis and the early onset of aging.A number of methods and tools have been developed to help elucidate the regulatory mechanisms of the two repair pathways in the past.In vitro biochemical assays employ 32P-labeled broken DNA fragments and cell extracts to evaluate DSB repair capacity.At DSB sites,several DSB repair factors form foci,which can be visualized through immunofluorescence and microscopy.Among them,phosphorylated H2AX at the Ser139 residue is often considered a DSB marker,and its formation and removal at different time points post the induction of DSBs can be used to reflect the repair capacity and genomic instability.In addition,by quantifying the kinetics of the recruitment of specific NHEJ and HR factors such as 53BP1,DNA-PKcs,MRE11,RPA2,and RAD51,one would be able to make judgments on whether NHEJ,HR,or both pathways is/are affected and sometimes at which steps DSB repair pathways are regulated.An alternative approach for kinetic analysis is to quantify the microirradiation-induced recruitment of repair factors.Moreover,comet assays are also utilized to measure DNA damage-induced genomic stability at the single-cell level.However,with these assays,it is still difficult to measure NHEJ and HR efficiency in a relatively less time-consuming and more quantitative manner.

关键词： double repair simultaneous

Machine learning-assisted systematical polymerization planning:case studies on reversible-deactivation radical polymerization

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Science China Chemistry 2021年第6期64卷 1039-1046页

作者： Yu Gu Peirong Lin chengda Zhou Mao Chen State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200433China Department of Civil and Environmental Engineering Princeton UniversityNew Jersey 08544USA

The combined influence of chemical composition,molecular weight(MW)and molecular weight distribution(D)on the functions and performances of polymeric materials necessitates simultaneous satisfaction of multidimensional requirements during polymer synthesis.However,the complexity of polymerization reactions often dissuades chemists when precisely accessing diversified polymer targets.Herein,we developed a machine learning(ML)-assisted systematical polymerization planning(SPP)platform for addressing this challenge.With ML model providing integrated navigation of the reaction space,this approach can conduct multivariate analysis to uncover complex interactions between the polymerization result and conditions,prescribing optimal reaction conditions to achieve discretionary polymer targets concerning three dimensions including chemical composition,MWandD values.Given the increasing importance of polymerization in advanced material engineering,this ML-assisted SPP platform provides a universal strategy to access tailored polymers with on-demand prediction of polymerization parameters.

关键词： polymerization synthetic methods synthesis planning photochemistry machine learning