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Chinese Journal of Polymer Science 2007年第6期25卷 635-640页

作者： qun-feng liu Si-dong Li Ping Zhang Yan-xun Lan Man-geng Lu College of Science Guangdong Ocean University Zhanjiang 524088 China Guangzhou Institute of Chemistry Chinese Academy of Sciences P.O. Box 1122 Guangzhou 510650 China

P（N-isopropylacrylamide）（PNIPAM） prepared by reversible addition fragmentation chain transfer （RAFT） polymerization exhibited gelation retardation. The intermediate before gelation was characterized and indicated the presence of branched or hyperbranched chains. The swelling behavior was investigated, and the gel by RAFT polymerization （RAFT gel） showed accelerated shrinking kinetics and higher swelling ratio comparing with conventional gels （CG）. The study was extended to gels prepared by using 2-hydroxy- 1-ethanethiol as chain transfer agent and by using low concentration solutions. The two systems also exhibited retardation effects and improved deswelling kinetics. The different swelling behaviors of these gels and CG could be attributed to the presence of dangling chains caused by gelation retardation.

关键词： Chain transfer Hyperbranched Graft Hydrogels.

Rapid Amplification of Flanking Sequences of a Known DNA Region by Partial Restriction Digestion and Hot Start PCR

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Agricultural Sciences in China 2008年第5期7卷 542-546页

作者： LOU qun-feng liu Qiang YANG Yin-gui CHEN Jin-feng State Key Laboratory of Crop Genetics and Germplasm Enhancement College of Horticulture Nanjing Agricultural University Nanjing210095 P.R.China

A simple and efficient method for cloning the flanking genomic sequences of a known DNA region is reported in this study. This method combined partial restriction endonuclease digestion, adaptor ligation, and a single round polymerase chain reaction. Total genomic DNA was partially digested with the frequent-cutting restriction enzyme Mse I. The partially digested products were ligated to an unphosphorylated adaptor. A hot start PCR amplification with Taq polymerase and dNTP was performed with a DNA-specific primer and the adaptor primer complementary to the adaptor and the Mse I recognition site. The amplified products were fractionated, cloned and sequenced. By this method, we cloned the downstream region of a gynoecious marker TG/CAC234 from cucumber （Cucumis sativus L.）.

关键词： Cucumis sativus L. Mse I partial digestion sequence cloning hot start PCR

Catalytic asymmetric(3+3)cycloaddition between different 2-indolylmethanols

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Science China Chemistry 2024年第8期67卷 2629-2636页

作者： Tianzhen Li Sijia liu Shufang Wu Qi Cheng qun Chen Yinchun Jiao Yuchen Zhang feng Shi School of Petrochemical Engineering School of Materials ScienceEngineeringChangzhou UniversityChangzhou 213164China Research Center of Chiral Functional Heterocycles School of Chemistry and Materials ScienceJiangsu Normal UniversityXuzhou 221116China School of Chemistry and Chemical Engineering Hunan University of Science and TechnologyXiangtan 411201China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007China

The catalytic asymmetric(3+3)cycloaddition between different 2-indolylmethanols has been established,in which a series of chiral indole-fused six-membered heterocycles were constructed in high yields with excellent *** work not only has established the first catalytic asymmetric cycloaddition between different 2-indolylmethanols but also provided a powerful strategy for constructing enantioenriched indole-fused six-membered ***,biological evaluation discovered some products with promising antitumor ***,theoretical calculations performed on the reaction pathway and activation mode provide an in-depth understanding of this catalytic asymmetric(3+3)cycloaddition among different 2-indolylmethanols,which will advance the understanding of the chemistry of indolylmethanols.

关键词： asymmetric organocatalysis chiral phosphoric acid cycloaddition enantioselectivity 2-indolylmethanol

Strong Limit Theorems for Weighted Sums under the Sub-linear Expectations

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 862-874页

作者： feng-xiang feng Ding-cheng WANG qun-ying WU Hai-wu HUANG School of Mathematics and Statistics Guilin University of TechnologyGuilin 541004China School of Mathematical Science University of Electronic Science and Technology of ChinaChengdu 611731China School of Science Guilin University of Aerospace TechnologyGuilin 541004China

In this article,we study strong limit theorems for weighted sums of extended negatively dependent random variables under the sub-linear *** establish general strong law and complete convergence theorems for weighted sums of extended negatively dependent random variables under the sub-linear *** results of strong limit theorems are more general than some related results previously obtained by Thrum(1987),Li et al.(1995)and Wu(2010)in classical probability space.

关键词： sub-linear expectation complete convergence complete moment convergence the maximal weighted sums

Procyanidin A_1 and its digestive products alleviate acrylamide-induced IPEC-J2 cell damage through regulating Keap1/Nrf2 pathway

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Food Science and Human Wellness 2024年第3期13卷 1475-1484页

作者： Fangfang Yan qun Lu Chengming Wang Rui liu College of Food Science and Technology Huazhong Agricultural UniversityWuhan 430070China Key Laboratory of Environment Correlative Dietology(Huazhong Agricultural University) Ministry of EducationWuhan 430070China Key Laboratory of Urban Agriculture in Central China Ministry of Agriculture and Rural AffairsWuhan 430070China

Our previous study has revealed that procyanidin A_(1)(A_(1))and its simulated digestive product(D-A,)can alleviate acrylamide(ACR)-induced intestine cell ***,the underlying mechanism remains *** this study,we elucidated the molecular mechanism for and D-A_(1) to alleviate ACR-stimulated IPEC-J2 cell *** slightly activated nuclear factor erythroid 2-related factor 2(Nrf2)signaling and its target genes,but this activation could not reduce intestine cell damage.A_(1) and D-A_(1) could alleviate ACR-induced cell damage,but the effect was abrogated in cells transiently transfected with Nrf2 small interfering RNA(siRNA).Further investigation confirmed that A_(1) and D-A_(1) interacted with Ketch-like ECH-associated protein 1(Keapl),which boosted the stabilization of Nrf2,subsequently promoted the translocation of Nrf2 into the nucleus,and further increased the expression of antioxidant proteins,thereby inhibiting glutathione(GSH)consumption,maintaining redox balance and eventually alleviating ACR-induced cell ***,there was no difference between A_(1) and D-A_(1) treated groups,indicating that A_(1) can tolerate gastrointestinal digestion and may be a potential compound to limit the toxicity of ACR.

关键词： Procyanidin A_1 Digestive products Acrylamide Nuclear factor erythroid 2-related factor 2(Nrf2) Intestinal cell damage

Cause analysis of expressway traffic accidents based on accident statistics of Hunan provincial expressway in 2012-2018

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Transportation Safety and Environment 2024年第1期6卷 83-92页

作者： Xinyu liu Shengjun Huang qun Chen Business school Foshan UniversityFoshan 528225GuangdongChina School of Traffic and Transportation Engineering Central South UniversityChangsha 410075HunanChina Hunan Provincial Expressway Traffic Police Station Law Enforcement DepartmentChangsha 410007HunanChina

Based on the 2012–2018 accident statistics on the Hunan Provincial Expressway in China,this paper analyses the proportion to which various factors contribute to accidents,as well as the trends over *** 2012 to 2018,the total number of general procedure handling accidents(*** accidents)increased first and then decreased,while the number of accidents and deaths per 1000 kilometres decreased year by *** total number of simple procedure handling accidents(*** accidents)increased year by year,but the number of accidents per 1000 kilometres remained relatively ***,fatigued driving,improper driving operation,failure to maintain a safe distance from the preceding vehicle and pedestrians entering the expressway are the main causes of general procedure handling *** to maintain a safe distance from the preceding vehicle as required and improper driving operation accounted for approximately 2/3 of the simple procedure handling *** view of the accidents caused by these factors,how to use law enforcement,education,science and technology and facilities construction to further reduce the occurrence of expressway traffic accidents is discussed.

关键词： expressway traffic accident cause analysis

Microbial phenolic metabolites 3-(3',4'-dihydroxyphenyl)propanoic acid and 3',4'-dihydroxyphenylacetic acid prevent obesity in mice fed high-fat diet

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Food Science and Human Wellness 2024年第1期13卷 327-338页

作者： Wanbing Chen Ruonan liu Xiaoling Zhu qun Lu Hong Yang Rui liu College of Food Science and Technology Huazhong Agricultural UniversityWuhan 430000China Key Laboratory of Environment Correlative Dietology(Huazhong Agricultural University) Ministry of educationWuhan 430000China Wuhan Engineering Research Center of Bee Products on Quality and Safety Control Wuhan 430000China Key Laboratory of Urban Agriculture in Central China Ministry of Agriculture and Rural AffairsWuhan 430000China Hubei Provincial Institute for Food Supervision and Test Wuhan 430070China

Obesity is associated with numerous metabolic disorders,and dietary polyphenols have been confirmed to have beneficial effects on the metabolism in ***,the effect of 3-(3’,4’-dihydroxyphenyl)propanoic acid(DHPA)and 3’,4’-dihydroxyphenylacetic acid(DHAA),two main metabolites of dietary polyphenols,on obesity remains poorly *** this study,DHPA and DHAA were found to alleviate obesity,as well as regulate insulin resistance,lipid metabolism,and oxidative stress response in high-fat diet(HFD)***,the 16S rRNA sequencing and UHPLC-Q-TOF/MS demonstrated that DHPA and DHAA only slightly disturbed the intestinal microbiome,but significantly altered the urine metabolome of HFD mice mainly by regulating pentose and glucuronate interconversion,tyrosine metabolism,pentose phosphate and tricarboxylic acid(TCA)cycle as indicated by metabolic pathway analysis based on Kyoto Encyclopedia of Genes and Genomes(KEGG)*** analysis revealed that the differential metabolites are strongly associated with body weight,blood glucose,insulin level,and superoxide dismutase(SOD)enzyme *** results revealed that DHPA and DHAA exert their anti-obesity effect by regulating important metabolites in the glucose,lipid and tyrosine metabolism pathways.

关键词： Obesity Dietary polyphenol metabolites Gut microbiota Metabonomics

The evolving views of hematopoiesis:from embryo to adulthood and from in vivo to in vitro

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Journal of Genetics and Genomics 2024年第1期51卷 3-15页

作者： Yifan Zhang feng liu Shandong Provincial Key Laboratory of Animal Cell and Developmental Biology School of Life SciencesShandong UniversityQingdaoShandong 266237China State Key Laboratory of Membrane Biology Institute of ZoologyInstitute for Stem Cell and RegenerationUniversity of Chinese Academy of SciencesChinese Academy of SciencesBeijing 100101China

The hematopoietic system composed of hematopoietic stem and progenitor cells(HSPCs)and their differentiated lineages serves as an ideal model to uncover generic principles of cell fate *** gastrulation onwards,there successively emerge primitive hematopoiesis(that produces specialized he-matopoietic cells),pro-definitive hematopoiesis(that produces lineage-restricted progenitor cells),and definitive hematopoiesis(that produces multipotent HSPCs).These nascent lineages develop in several transient hematopoietic sites and finally colonize into lifelong hematopoietic *** development and maintenance of hematopoietic lineages are orchestrated by cell-intrinsic gene regulatory networks and cell-extrinsic microenvironmental *** to the progressive methodology(e.g.,high-throughput lineage tracing and single-cell functional and omics analyses),our understanding of the developmental origin of hematopoietic lineages and functional properties of certain hematopoietic organs has been updated;meanwhile,new paradigms to characterize rare cell types,cell heterogeneity and its causes,and comprehensive regulatory landscapes have been ***,we review the evolving views of HSPC biology during developmental and postnatal ***,we discuss recent advances in the in vitro induction and expansion of HSPCs,with a focus on the implications for clinical applications.

关键词： Hematopoietic stem and progenitor cell Developmental hematopoiesis Postnatal hematopoiesis In vitro hematopoiesis

Enlarged interlayer of separator coating enabling high-performance lithiumsulfur batteries

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Frontiers of Chemical Science and Engineering 2024年第2期18卷 103-112页

作者： Yanqi feng Hui liu Xiaoting liu Qiongqiong Lu School of Materials&Environment Engineering Chengdu Technological UniversityChengdu 611730China School of Materials Science and Engineering Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic MaterialsShaanxi University of Science and TechnologyXi’an 710021China Green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhou 450001China Institute of Materials Henan Key Laboratory of Advanced Conductor MaterialsHenan Academy of SciencesZhengzhou 450046China Leibniz Institute for Solid State and Materials Research(IFW) Dresden e.V.Dresden 01069Germany

Lithiumsulfur batteries have been intensively studied due to their high theoretical energy density and abundant sulfur resources. However, their commercial application is hindered by the low redox kinetics and high sulfur losses. In principle, in the design of cathodes and separators, the adsorption toward lithium-polysulfides should be enhanced and the conversion of soluble high-order lithium-polysulfides should be catalyzed. Herein, a KV_(3)O_(8)·0.75H_(2)O separator is designed as an effective lithium-polysulfides mediator in lithiumsulfur batteries. The intercalated K+ would enlarge the interlayer spacing of vanadium oxides, preventing the collapse of the layer structure and improving the electrical/ion conductivity of the interface. Moreover, the KV_(3)O_(8)·0.75H_(2)O modified separator possess a prior adsorption and high redox kinetics toward lithium-polysulfides due to the enhanced diffusion kinetics, which guarantees the high-rate capability and efficient utilization of sulfur. As a result, lithiumsulfur batteries exhibit a high capacity of 1362 mAh·g^(-1) and a long lifespan with a low capacity loss of 0.073% per cycle. This work may provide an alternative way to establish a functional separator to balance the adsorption and conversion of polysulfides during the redox back and forth.

关键词： lithium kinetics adsorption

Quantum phase transition of the Jaynes-Cummings model

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 1-9页

作者： Cheng liu Jin-feng Huang Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Key Laboratory for Matter Microstructure and Function of Hunan ProvinceDepartment of Physics and Synergetic Innovation Center for Quantum Effects and ApplicationsInstitute of Interdisciplinary StudiesHunan Normal UniversityChangsha 410081China

Herein,we propose an experimentally feasible scheme to show the quantum phase transition of the Jaynes-Cummings(JC)model by modulating the transition frequency of a two-level system in a quantum Rabi model with strong *** tuning the modulation frequency and amplitude,the ratio of the effective coupling strength of the rotating terms to the effective cavity(atomic transition)frequency can enter the deep-strong coupling regime,while the counter-rotating terms can be ***,a deep-strong JC model is *** ratio of the coupling strength to resonance frequencies in the deep-strong JC model is two orders of magnitude larger than the corresponding ratio in the original quantum Rabi *** scheme can be employed in atom-cavity resonance and off-resonance cases,and it is valid over a broad *** nonzero average cavity photons of the ground state indicate the emergence of a quantum phase ***,we demonstrate the dependence of the phase diagram on the atom-cavity detuning and modulation *** the parameters used in our scheme are within the reach of current experimental *** scheme provides a new mechanism for investigating the critical phenomena of finite-sized systems without requiring classical field limits,thereby opening a door for studying fundamental quantum phenomena occurring in the ultrastrong and even deep-strong coupling regimes.

关键词： Jaynes-Cummings model quantum phase transition frequency modulation