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Partners in Epoxide Copolymerization Catalysis:Approach to High Activity and Selectivity

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Chinese Journal of Polymer Science 2022年第11期40卷 1331-1348页

作者： xiao-bing lu Bai-Hao Ren State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian 116024China

The ring-opening alternating copolymerization processes of epoxides with small-molecule monomers,such as carbon dioxide(CO_(2)),carbonyl sulfide(COS)and cyclic anhydrides,are powerful strategies for preparing polymeric materials with degradable carbonate/ester/thiocarbonate main-chain backbone units.The catalysts selected for copolymerization processes play crucial roles in determining their reaction rates and productivities,as well as the selectivity,regio-and stereochemistry,compositions,and the molecular weights of their resultant copolymers.These processes often generate undesirable byproducts such as polyether or ether linkages dispersed randomly within the copolymer's chain,and/or more thermodynamically stable cyclic products.In this account,we outline our efforts of over a dozen years on developing highly active well-defined metal catalysts based on inter-and intra-molecular synergistic strategies to selectively produce completely alternating copolymers from epoxides and various small-molecule monomers.Much attention was paid to the enantioselective resolution copolymerization processes of racemic epoxides via regioselective ring-openings,and the asymmetric copolymerization processes of meso-epoxides with CO_(2),COS,or cyclic anhydrides via dissymmetrical ring-openings using multichiral catalytic systems,and affording isotactic copolymers with main-chain chirality.In addition,this account provides a thorough mechanistic understanding of the high reactivities,excellent selectivity,and unprecedented stereochemical controls of these copolymerization systems,mediated by interand intramolecular synergistic catalysis.

关键词： Epoxide Ring-opening copolymerization Synergistic catalysis CO_(2) Stereochemistry control

Asymmetric Catalytic Polymerization: Advances and Challenges

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高分子科学：英文版 2023年第1期41卷 1-2页

作者： xiao-bing lu State Key Laboratory of Fine Chemicals Frontiers Science Center for Smart MaterialsDalian University of Technology

Most naturally occurring biomacromolecules are optically active owing to their unique chiral structural units and/or helical conformations.Some of them show specific functionalities,such as supersensitive responses to external stimuli,highly selective recognition abilities,superior mechanical properties,and excellent catalytic activity under extremely mild conditions.These functionalities result from the unique chiral structural units and orderly arrangement of building blocks in the main-chain backbones of these biological macromolecules,such as enzymes,genes,and proteins.Indeed,the sequence and stereochemistry of the repeating units in a polymeric chain also have significant influence on their material performance.Therefore,construction of functional polymers with precise control of chirality and sequence,similar to those in living systems,is of great significance.

关键词： precise Catalytic bones

Decentralized Optimal Control and Stabilization of Interconnected Systems With Asymmetric Information

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 698-707页

作者： Na Wang xiao Liang Hongdan Li xiao lu the College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao 266000China the School of Automation and Electrical Engineering Linyi UniversityLinyi 276000China the College of Energy Storage Technology Shandong University of Science and TechnologyQingdao 266000China

The paper addresses the decentralized optimal control and stabilization problems for interconnected systems subject to asymmetric information.Compared with previous work,a closed-loop optimal solution to the control problem and sufficient and necessary conditions for the stabilization problem of the interconnected systems are given for the first time.The main challenge lies in three aspects:Firstly,the asymmetric information results in coupling between control and estimation and failure of the separation principle.Secondly,two extra unknown variables are generated by asymmetric information(different information filtration)when solving forward-backward stochastic difference equations.Thirdly,the existence of additive noise makes the study of mean-square boundedness an obstacle.The adopted technique is proving and assuming the linear form of controllers and establishing the equivalence between the two systems with and without additive noise.A dual-motor parallel drive system is presented to demonstrate the validity of the proposed algorithm.

关键词： Asymmetric information decentralized control forwardbackward stochastic difference equations interconnected system stalibization

On Minor Left Prime Factorization Problem for Multivariate Polynomial Matrices

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Journal of Systems Science & Complexity 2024年第3期37卷 1295-1307页

作者： lu Dong WANG Dingkang xiao Fanghui School of Mathematics Southwest Jiaotong UniversityChengdu 610031China KLMM Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China MOE-LCSM School of Mathematics and StatisticsHunan Normal UniversityChangsha 410081China

A new necessary and sufficient condition for the existence of minor left prime factorizations of multivariate polynomial matrices without full row rank is presented.The key idea is to establish a relationship between a matrix and any of its full row rank submatrices.Based on the new result,the authors propose an algorithm for factorizing matrices and have implemented it on the computer algebra system Maple.Two examples are given to illustrate the effectiveness of the algorithm,and experimental data shows that the algorithm is efficient.

关键词： Free modules Grobner bases minor left prime(MLP) multivariate polynomial matrices polynomial matrix factorizations

Severe liver injury and clinical characteristics of occupational exposure to 2-amino-5-chloro-N,3-dimethylbenzamide: A case series

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Hepatobiliary & Pancreatic Diseases International 2024年第2期23卷 186-194页

作者： Meng-xiao Feng Hua Zou Yuan-Qiang lu Department of Emergency Medicine The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Key Laboratory for Diagnosis and Treatment of Aging and Physic-chemical Injury Diseases of Zhejiang Province Hangzhou 310003China Occupational Health and Radiation Protection Institute Zhejiang Provincial Center for Disease Control and PreventionHangzhou 310051China

Background:The 2-amino-5-chloro-N,3-dimethylbenzamide is a key intermediate in the synthesis of pesticides and pharmaceuticals.However,no literature currently exists on 2-amino-5-chloro-N,3-dimethylbenzamide poisoning in humans.This study aimed to reveal the health hazard of this chemical for humans and summarize the clinical characteristics of patients with occupational 2-amino-5-chloro-N,3-dimethylbenzamide poisoning.Methods:This observational study included four patients with 2-amino-5-chloro-N,3-dimethylbenzamide poisoning from June 2022 to July 2022.The entire course of the incidents was described in detail.Blood 2-amino-5-chloro-N,3-dimethylbenzamide concentrations were detected by a mass spectrometer.Hema-toxylin and eosin staining was performed to assess liver injury,and immunofluorescence was used to evaluate hepatic mitophagy.Results:The 2-amino-5-chloro-N,3-dimethylbenzamide powder(99%purity)entered the human body mainly via the skin and respiratory tract due to poor personal protective measures.The typical course of 2-amino-5-chloro-N,3-dimethylbenzamide poisoning was divided into latency,rash,fever,organic dam-age,and recovery phases in accordance with the clinical evolution.Rash and fever may be the important premonitory symptoms for further organ injuries.The chemical was detected in the blood of all patients and caused multiple organ injuries,predominantly liver injury,including kidney,myocardium,and micro-circulation.Three patients recovered smoothly after comprehensive treatments,including artificial liver therapy,continuous renal replacement therapy,glucocorticoids,and other symptomatic and supportive treatments.One patient survived by liver transplantation.The postoperative pathological findings of the removed liver showed acute liver failure,and immunofluorescence staining confirmed the abundance of mitophagy in residual hepatocytes.Conclusions:This study is the first to elaborate the clinical characteristics of patients with 2-amino-5-chloro-N,3-dimethylbenzamide poisoning.The chemical enter

关键词： 2-amino-5-chloro-N,3-dimethylbenzamide Poisoning Clinical characteristics Liver injury

Global trends in diabetic eye disease research from 2012 to 2021

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Neural Regeneration Research 2024年第10期19卷 2310-2320页

作者： Yuan Yuan Shangli Ji Yali Song Zhaodi Che lu xiao Shibo Tang Jia xiao Aier School of Ophthalmology Central South UniversityChangshaHunan ProvinceChina Changsha Aier Eye Hospital ChangshaHunan ProvinceChina Aier Eye Institute ChangshaHunan ProvinceChina Department of Metabolic and Bariatric Surgery The First Affiliated Hospital of Jinan UniversityGuangzhouGuangdong ProvinceChina

Diabetic eye disease refers to a group of eye complications that occur in diabetic patients and include diabetic retinopathy, diabetic macular edema, diabetic cataracts, and diabetic glaucoma. However, the global epidemiology of these conditions has not been well characterized. In this study, we collected information on diabetic eye disease-related research grants from seven representative countries––the United States, China, Japan, the United Kingdom, Spain, Germany, and France––by searching for all global diabetic eye disease journal articles in the Web of Science and Pub Med databases, all global registered clinical trials in the Clinical Trials database, and new drugs approved by the United States, China, Japan, and EU agencies from 2012 to 2021. During this time period, diabetic retinopathy accounted for the vast majority(89.53%) of the 2288 government research grants that were funded to investigate diabetic eye disease, followed by diabetic macular edema(9.27%). The United States granted the most research funding for diabetic eye disease out of the seven countries assessed. The research objectives of grants focusing on diabetic retinopathy and diabetic macular edema differed by country. Additionally, the United States was dominant in terms of research output, publishing 17.53% of global papers about diabetic eye disease and receiving 22.58% of total citations. The United States and the United Kingdom led international collaborations in research into diabetic eye disease. Of the 415 clinical trials that we identified, diabetic macular edema was the major disease that was targeted for drug development(58.19%). Approximately half of the trials(49.13%) pertained to angiogenesis. However, few drugs were approved for ophthalmic(40 out of 1830;2.19%) and diabetic eye disease(3 out of 1830;0.02%) applications. Our findings show that basic and translational research related to diabetic eye disease in the past decade has not been highly active, and has yielded few new treatment methods and newly approved drugs.

关键词： clinical trials diabetic cataracts diabetic eye disease diabetic glaucoma diabetic macular edema diabetic retinopathy drug development global research publication research grant

Experimental distillation of tripartite quantum steering with an optimal local filtering operation

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Photonics Research 2024年第3期12卷 552-562页

作者： QIAN-XI ZHANG xiao-XU FANG HE lu School of Physics State Key Laboratory of Crystal MaterialsShandong UniversityJinan 250100China Shenzhen Research Institute of Shandong University Shenzhen 518057China

Multipartite Einstein-Podolsky-Rosen(EPR)steering admits multipartite entanglement in the presence of uncharacterized verifiers,enabling practical applications in semi-device-independent protocols.Such applications generally require stronger steerability,while the unavoidable noise weakens steerability and consequently degrades the performance of quantum information processing.Here,we propose the local filtering operation that can maximally distill genuine tripartite EPR steering from N copies of three-qubit generalized Greenberger-Horne-Zeilinger states,in the context of two semi-device-independent scenarios.The optimal filtering operation is determined by the maximization of assemblage fidelity.Analytical and numerical results indicate the advantage of the proposed filtering operation when N is finite and the steerability of initial assemblages is weak.Experimentally,a proof-of-principle demonstration of two-copy distillation is realized with the optical system.The advantage of the optimal local filtering operation is confirmed by the distilled assemblage in terms of higher assemblage fidelity with perfectly genuine tripartite steerable assemblages,as well as the greater violation of the inequality to witness genuine tripartite steerable assemblages.Our results benefit the distillation of multipartite EPR steering in practice,where the number of copies of initial assemblages is generally finite.

关键词： filtering distillation optimal

Fast spreading of surface ozone in both temporal and spatial scale in Pearl River Delta

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Journal of Environmental Sciences 2024年第3期137卷 540-552页

作者： Tianhui Cao Haichao Wang Lei Li xiao lu Yiming Liu Shaojia Fan School of Atmospheric Sciences Sun Yat-sen University and Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Guangdong Provincial Observation and Research Station for Climate Environment and Air Quality Change in the Pearl River Estuary Key Laboratory of Tropical Atmosphere-Ocean SystemMinistry of EducationZhuhai 519082China

Surface ozone(O_(3))is a major air pollutant and draw increasing attention in the Pearl River Delta(PRD),China.Here,we characterize the spatial-temporal variability of ozone based on a dataset obtained from 57 national monitoring sites during 2013-2019.Our results show that:(1)the seasonal difference of ozone distribution in the inland and coastal areas was significant,which was largely affected by the wind pattern reversals related to the East Asian monsoon,and local ozone production and destruction;(2)the daily maximum 8hr average(MDA8 O_(3))showed an overall upward trend by 1.11 ppbv/year.While the trends in the nine cities varied differently by ranging from-0.12 to 2.51 ppbv/year.The hot spots of ozone were spreading to southwestern areas from the central areas since 2016.And ozone is becoming a year-round air pollution problem with the pollution season extending to winter and spring in PRD region.(3)at the central and southwestern PRD cities,the percentage of exceedance days from the continuous type(defined as≥3 days)was increasing.Furthermore,the ozone concentration of continuous type was much higher than that of scattered exceedance type(lution days and highlight the great challenge in mitigation of O_(3)pollution in these cities.

关键词： Surface ozone pollution Ozone trend Spatial and temporal variability Pearl River Delta Pollution mitigation

Association of complement components with risk of colorectal cancer:A systematic review and meta-analysis

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 2168-2180页

作者： xiao-Lin Zhu lu Zhang Su-Xia Qi Department of Gastroenterology Qingdao Municipal HospitalQingdao 266071Shandong ProvinceChina Department of Medical Administration Qingdao Municipal HospitalQingdao 266071Shandong ProvinceChina

BACKGROUND Complement components could contribute to the tumor microenvironment and the systemic immune response.Nevertheless,their role in colorectal cancer(CRC)remains a contentious subject.AIM To elucidate the relationship between complement components and CRC risk and clinical characteristics.METHODS Searches were conducted in PubMed,the Cochrane Library,and the China National Knowledge Infrastructure database until June 1,2023.We included cohort studies encompassing participants aged≥18 years,investigating the association between complement components and CRC.The studies were of moderate quality or above,as determined by the Agency for Healthcare Research and Quality.The meta-analysis employed fixed-effects or random-effects models based on the I^(2)test,utilizing risk ratio(RR)and their corresponding 95%confidence interval(CI)for outcomes.Sensitivity and subgroup analyses were performed to validate the robustness of the collective estimates and identify the source of heterogeneity.RESULTS Data from 15 studies,comprising 1631 participants that met the inclusion criteria,were included in the meta-analysis.Our findings indicated that protein levels of cluster of differentiation 46(CD46)(RR=3.66,95%CI:1.75-7.64,PluSION Our analysis underscores that increased levels of specific complement components are associated with a heightened risk of CRC,emphasi

关键词： Complement components Colorectal cancer Lymph node metastasis Systematic review Meta-analysis