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Rational surface charge engineering of haloalkane dehalogenase for boosting the enzymatic performance in organic solvent solutions

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Chinese Journal of Chemical Engineering 2024年第1期65卷 276-285页

作者： Yin wu yan Sun Department of Biochemical Engineering School of Chemical Engineering and Technology and Key Laboratory of Systems Bioengineering and Frontiers Science Center for Synthetic Biology(Ministry of Education)Tianjin UniversityTianjin 300350China

Biocatalysis in organic solvents(OSs)has numerous important applications,but native enzymes in OSs often exhibit limited catalytic performance.Herein,we proposed a computation-aided surface charge engineering strategy to improve the catalytic performance of haloalkane dehalogenase DhaA in OSs based on the energetic analysis of substrate binding to the DhaA surface.Several variants with enhanced OS resistance were obtained by replacing negative charged residues on the surface with positive charged residue(Arg).Particularly,a four-substitution variant E16R/E93R/E121R/E257R exhibited the best catalytic performance(five-fold improvement in OS resistance and seven-fold half-life increase in 40%(vol)dimethylsulfoxide).As a result,the overall catalytic performance of the variant could be at least 26 times higher than the wild-type DhaA.Fluorescence spectroscopy and molecular dynamics simulation studies revealed that the residue substitution mainly enhanced OS resistance from four aspects:(a)improved the overall structural stability,(b)increased the hydrophobicity of the local microenvironment around the catalytic triad,(c)enriched the hydrophobic substrate around the enzyme molecule,and(d)lowered the contact frequency between OS molecules and the catalytic triad.Our findings validate that computationaided surface charge engineering is an effective and ingenious rational strategy for tailoring enzyme performance in OSs.

关键词： Surface charge engineering Organic solvent resistance Molecular dynamics simulation Haloalkane dehalogenase

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Advances of Electrochemical and Electrochemiluminescent Sensors Based on Covalent Organic Frameworks

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Nano-Micro Letters 2024年第2期16卷 395-422页

作者： Yue Cao Ru wu yan‑yan Gao yang Zhou Jun‑Jie Zhu Key Laboratory for Organic Electronics and Information Displays(KLOEID)and Institute of Advanced Materials(IAM) Nanjing University of Posts and Telecommunications(NJUPT)Nanjing 210023People’s Republic of China State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023People’s Republic of China

Covalent organic frameworks(COFs),a rapidly developing category of crystalline conjugated organic polymers,possess highly ordered structures,large specific surface areas,stable chemical properties,and tunable pore microenvironments.Since the first report of boroxine/boronate ester-linked COFs in 2005,COFs have rapidly gained popularity,showing important application prospects in various fields,such as sensing,catalysis,separation,and energy storage.Among them,COFs-based electrochemical(EC)sensors with upgraded analytical performance are arousing extensive interest.In this review,therefore,we summarize the basic properties and the general synthesis methods of COFs used in the field of electroanalytical chemistry,with special emphasis on their usages in the fabrication of chemical sensors,ions sensors,immunosensors,and aptasensors.Notably,the emerged COFs in the electrochemiluminescence(ECL)realm are thoroughly covered along with their preliminary applications.Additionally,final conclusions on state-of-the-art COFs are provided in terms of EC and ECL sensors,as well as challenges and prospects for extending and improving the research and applications of COFs in electroanalytical chemistry.

关键词： Covalent organic frameworks Electrochemistry Electrochemiluminescence Sensors

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Cobalt doping amount determines dominant reactive species in peroxymonosulfate activation via porous carbon catalysts co-doped by cobalt and nitrogen

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Journal of Environmental Sciences 2024年第4期138卷 212-226页

作者： Xiang Li Limeng wu Aiqin Zhang Shaohua wu yan Lin Chunping yang Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle Nanchang Hangkong UniversityNanchang 330063China Academy of Environmental and Resource Sciences School of Environmental Science and EngineeringGuangdong University of Petrochemical TechnologyMaoming 525000China College of Environmental Science and Engineering Hunan University and Key Laboratory of Environmental Biology and Pollution Control(Hunan University)Ministry of EducationChangsha 410082China

Switching the reaction routes in peroxymonosulfate(PMS)-based advanced oxidation processes have attracted much attention but remain challenging.Herein,a series of Co-N/C catalysts with different compositions and structures were prepared by using bimetallic zeolitic imidazolate frameworks based on ZIF-8 and ZIF-67(x Zn/Co-ZIFs).Results show that Co doping amount could mediate the transformation of the activation pathway of PMS over CoN/C.When Co doping amount was less than 10%,the constructed x Co-N/C/PMS system(x≤10%)was singlet oxygen-dominated reaction;however further increasing Co doping amount would lead to the generation and coexistence of sulfate radicals and high-valent cobalt,besides singlet oxygen.Furthermore,the nitrogen-coordinated Co(Co-NX)sites could serve as main catalytically active sites to generate singlet oxygen.While excess Co doping amount caused the formation of Co nanoparticles from which leached Co ions were responsible for the generation of sulfate radicals and high-valent cobalt.Compared to undoped N/C,Co doping could significantly enhance the catalytic performance.The 0.5%Co-N/C could achieve the optimum degradation(0.488 min^(-1))and mineralization abilities(78.4%)of sulfamethoxazole among the investigated Co-N/C catalysts,which was superior to most of previously reported catalysts.In addition,the application prospects of the two systems in different environmental scenarios(pH,inorganic anions and natural organic matter)were assessed and showed different degradation behaviors.This study provides a strategy to regulate the reactive species in PMS-based advanced oxidation process.

关键词： Peroxymonosulfate Sulfate radical Singlet oxygen Cobalt Zeolitic imidazolate framework Advanced oxidation process

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Asymptomatic recurrence in patients with pulmonary embolism

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中华医学杂志(英文版) 2024年第9期137卷 2024 Mar 21页

作者： Hu Song Wang Lei Tan Jiangshan Fang Wei Ma Xinghong Guo Tingting Gao Xin wu yan Zhou Yuzi Wang Li Hua Lu State Key Laboratory of Cardiovascular Disease National Center for Cardiovascular Diseases Fuwai Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing China Department of Nuclear Medicine National Center for Cardiovascular Diseases Fuwai Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing China Key Laboratory of Pulmonary Vascular Medicine Department of Cardiology National Clinical Research Center of Cardiovascular Diseases National Center for Cardiovascular Diseases Fuwai Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing China Fuwai Shenzhen Hospital Chinese Academy of Medical Sciences Shenzhen Guangdong China

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Exosome-encapsulated lncRNA HOTAIRM1 contributes to PM_(2.5)-aggravated COPD airway remodeling by enhancing myofibroblast differentiation

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Science China(Life Sciences) 2024年第5期67卷 970-985页

作者： Huaqi Guo Luo Fei Hengyi Yu yan Li yan Feng Shaowei wu yan Wang The Ninth People’s Hospital of Shanghai Jiao Tong University School of Medicine Shanghai 200011China School of Public Health Shanghai Jiao Tong University School of MedicineShanghai 200020China Department of Occupational and Environmental Health Sciences School of Public HealthXi’an Jiao Tong University Health Science CenterXi’an 710049China

Emphysema,myofibroblast accumulation and airway remodeling can occur in the lungs due to exposure to atmospheric pollution,especially fine particulate matter(PM_(2.5)),leading to chronic obstructive pulmonary disease(COPD).Specifically,bronchial epithelium-fibroblast communication participates in airway remodeling,which results in COPD.An increasing number of studies are now being conducted on the role of exosome-mediated cell-cell communication in disease pathogenesis.Here,we investigated whether exosomes generated from bronchial epithelial cells could deliver information to normal stromal fibroblasts and provoke cellular responses,resulting in airway obstruction in COPD.We studied the mechanism of exosome-mediated intercellular communication between human bronchial epithelial(HBE) cells and primary lung fibroblasts(pLFs).We found that PM_(2.5)-induced HBE-derived exosomes promoted myofibroblast differentiation in pLFs.Then,the exosomal lncRNA expression profiles derived from PM_(2.5)-treated HBE cells and nontreated HBE cells were investigated using an Agilent Human LncRNA Array.Combining coculture assays and direct exosome treatment,we found that HBE cell-derived exosomal HOTAIRM1 facilitated the myofibroblast differentiation of pLFs.Surprisingly,we discovered that exosomal HOTAIRM1 enhanced p LF proliferation to secrete excessive collagen secretion,leading to airway obstruction by stimulating the TGF-β/SMAD3 signaling pathway.Significantly,PM_(2.5)reduced FEV1/FVC and FEV1 and increased the level of serum exosomal HOTAIRM1 in healthy people;moreover,serum exosomal HOTAIRM1 was associated with PM_(2.5)-related reductions in FEV1/FVC and FVC.These findings show that PM_(2.5)triggers alterations in exosome components and clarify that one of the paracrine mediators of myofibroblast differentiation is bronchial epithelial cell-derived HOTAIRM1,which has the potential to be an effective prevention and therapeutic target for PM_(2.5)-induced COPD.

关键词： PM2.5 exosomal lncRNAs HOTAIRM1 chronic obstructive pulmonary disease

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Sport medicine among the past three decades in China

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中华医学杂志(英文版) 2024年第7期137卷 757-761页

作者： Ao Yingfang yan Wenqiang wu Yue Institute of Sports Medicine of Peking University Beijing 100191 China

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Multi-endpoint assays reveal more severe toxicity induced by chloraminated effluent organic matter than chloraminated natural organic matter

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Journal of Environmental Sciences 2024年第1期135卷 310-317页

作者： Hai-yan Wang De-Xiu wu Ye Du Xiao-Tong Lv Qian-Yuan wu State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Environmental Protection Key Laboratory of Microorganism Application and Risk Control Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental SafetyTsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China College of Architecture and Environment Sichuan UniversityChengdu 610000China

Disinfection by chloramination produces toxic byproducts and the difference in toxicity of reclaimed and drinking water treated by chloramination remains unclear.This study investigated cytotoxic effects at the same concentrations of dissolved organic matter and showed that chloraminated effluent organic matter(EfOM)induced 1.7 times higher cytotoxicity than chloraminated natural organic matter(NOM)applied to simulate drinking water.Chloraminated EfOM induced more reactive nitrogen species than chloraminated NOM,and chloraminated EfOM and NOM induced similar and higher levels of reactive oxygen species than the negative control,respectively.Consequently,intracellular macromolecule damage indicated by DNA/RNA damage marker 8–hydroxy-(deoxy)guanosine and the intracellular protein carbonyl concentration induced by chloraminated EfOM was higher and slightly more than that induced by chloraminated NOM,respectively.These data were consistent with the effects on cell physiological processes.Cell cycle arrest mainly occurred in G2 phase by chloraminated EfOM and NOM.Early apoptotic cells,which could return to normal,increased upon exposure to high concentrations of chloraminated EfOM and NOM.Moreover,necrotic cells were significantly increased from 0.5%to 2.5%when the concentration increased from 20-to 60-fold chloraminated EfOM,but were not obviously changed by chloraminated NOM.These results indicated that the comprehensive intracellular changes induced by toxic substances in chloraminated EfOM were more irreversible and induced more cell death than chloraminated NOM.

关键词： Cytotoxicity Intracellular active nitrogen/oxygen Intracellular oxidative damage Cell necrosis Reclaimed water

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A buffer overflow detection and defense method based on RiSC-V instruction set extension

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Cybersecurity 2024年第2期7卷 28-43页

作者： Chang Liu yan-Jun wu Jing-Zheng wu Chen Zhao Intelligent Software Research Center Institute of SoftwareChinese Academy of SciencesBejingChina University of Chinese Academy of Sciences BeijingChina State Key Laboratory of Computer Science Institute of SoftwareChinese Academy of SciencesBeijingChina

Buffer overflow poses a serious threat to the memory security of modern operating systems.It overwrites the con-tents of other memory areas by breaking through the buffer capacity limit,destroys the system execution environ-ment,and provides implementation space for various system attacks such as program control flow hijacking.That makes it a wide range of harms.A variety of security technologies have been proposed to deal with system security problems including buffer overflow.For example,No eXecute(NX for short)is a memory management technology commonly used in Harvard architecture.It can refuse the execution of code which residing in a specific memory,and can effectively suppress the abnormal impact of buffer overflow on control flow.Therefore,in recent years,it has also been used in the field of system security,deriving a series of solutions based on NX technology,such as ExecShield,DEP,StackGuard,etc.However,these security solutions often rely too much on the processor archi-tecture so that the protection coverage is insufficient and the accuracy is limited.Especially in the emerging system architecture field represented by RiSC-V,there is still a lack of effective solutions for buffer overflow vulnerabilities.With the continuous rapid development of the system architecture,it is urgent to develop defense methods that are applicable to different system application environments and oriented to all executable memory spaces to meet the needs of system security development.Therefore,we propose BOP,A new system memory security design method based on RISC-V extended instructions,to build a RISC-V buffer overflow detection and defense system and deal with the buffer overflow threat in RIsC-V.According to this method,NX technology can be combined with program control flow analysis,and Nx bit mechanism can be used to manage the executability of memory space,so as to achieve a more granular detection and defense of buffer overflow attacks that may occur in RISC-V system environment.In addition,The memory management an

关键词： RISc-V Operating system security Buffer overflow Control flow hijacking Nx bit Xibop

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Dynamic emission characteristics and control strategies of air pollutants from motor vehicles in downtown Beijing,China

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Journal of Environmental Sciences 2024年第2期136卷 637-646页

作者： yan Shen Tongran wu Aiping Lian Jie Gao Fei Peng Guohua Song Xuefang wu yangyang Cui Xinyu Liu Yunfei Wan Jing yan Yifeng Xue National Engineering Research Center of Urban Environmental Pollution Control Beijing Municipal Research Institute of Eco-Environmental ProtectionBeijing 100037China Beijing Municipal Ecology and Environment Bureau Beijing 100048China Beijing Jiaotong University Beijing 100091China

This study combined the real-time monitoring and investigation of traffic flows to comprehensively analyze the road traffic flow and vehicle structure in downtown Beijing.A dynamic emission inventory of motor vehicle air pollutants in downtown Beijing in 2021 was established,and the impact of these emissions on air quality was simulated and quantified,and different emission reduction control scenarios were proposed to evaluate their environmental improvement effects and explore measures to mitigate the impact of pollution emissions.The results show that the high traffic flow and the structure of the motor vehicle emissions in downtown Beijing are the main causes of severe motor vehicle pollution.Monitoring data shows that traffic flow in central Beijing is dominated by small passenger vehicles,while the vehicle mix is better than in other regions,with 72.0%of vehicles meeting"National V"or higher emission standards.However,to achieve higher air quality goals,further reducing vehicle emissions is necessary.Based on dynamic traffic flow,the average daily emissions of nitrogen oxides(NOX),particulate matters(PM_(2.5))and volatile organic compounds(VOC)from motor vehicles in central Beijing are 17.7 tons,0.6 tons and 14.0 tons,respectively,accounting for 23.0%of the city’s average daily motor vehicle emissions.If a zero-emission zone for motor vehicles were implemented in central Beijing,the annual average emission level of pollutants will be reduced by 10.4%to 21.0%.The designation of ultra-low emission zones for motor vehicles could be effective in improving the air quality in the center of Beijing.

关键词： Motor vehicle Air pollutant Emission characteristics Control strategy Beijing

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Selection Method for New Energy Output Guaranteed Rates Considering Optimal Energy Storage Configuration

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 539-547页

作者： Xin Cheng Tong wu Wei Yao yan yang Guangdong Power Grid Corporation Guangzhou 510620China State Key Laboratory of Advanced Electromagnetic Engineering and Technology and School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China

The output of new energy represented by wind power and photovoltaic power features volatility and randomness. It is a practical approach to use the guaranteed rate with statistical characteristics to analyze the output coefficient of new energy. However, there is a lack of analysis and demonstration on the value of the new energy output guaranteed rate. To solve this problem, a selection method for the new energy output guaranteed rate considering optimal energy storage configuration is proposed. First, the influence of the new energy output guaranteed rate on the new energy output coefficient is analyzed. Secondly, with the goal of minimizing the comprehensive costs, an optimal configuration model of energy storage based on the output guaranteed rate of new energy is constructed, and particle swarm optimization is used for the optimization solution. Then, according to the optimal energy storage configuration results under different guaranteed rates, a reasonable new energy output guaranteed rate is determined by maximizing the comprehensive benefits obtained from energy storage. Finally, an example applied to the power grid in an area of Guangdong in Southern China is provided to illustrate the effectiveness of the proposed method.

关键词： Energystorage optimization guaranteed output guaranteed rate new energy consumption

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