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Global Stability of a Mumps Transmission Model with Quarantine Measure

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Acta Mathematicae Applicatae Sinica 2021年第4期37卷 665-672页

作者： Yu-zhen BAI xiao-jing WANG song-bai GUO School of Science Beijing University of Civil Engineering and ArchitectureBeijing102616China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing100190China

In this paper,a model of mumps transmission with quarantine measure is proposed and then the control reproduction number Rc of the model is *** model admits a unique endemic equilibrium P*if and only if Rc>1,while the disease-free equilibrium P0 always *** using the technique of constructing Lyapunov functions and the generalized Lyapunov-LaSalle theorem,we first show that the equilibrium P0 is globally asymptotically stable(GAS)if Rc≤1;second,we prove that the equilibrium P*is GAS if Rc>*** results reveal that mumps can be eliminated from the community for Rc≤1 and it will be persistent for Rc>1,and quarantine measure can also effectively control the mumps transmission.

关键词： mumps transmission model control reproduction number quarantine measure global stability

Mechanisms involved in ceramide-induced cell cycle arrest in human hepatocarcinoma cells

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World Journal of Gastroenterology 2007年第7期13卷 1129-1134页

作者： jing Wang xiao-Wen Lv Jie-Ping Shi xiao-song Hu Research Center for Eco-Environmental Sciences The Chinese Academy of Sciences Beijing 100085 China Feed Research Institute Chinese Academy ofAgricultural Sciences Beijing 100081 China College of Food Science andNutritional Engineering China Agricultural University BeijingChina

AIM： To investigate the effect of ceramide on the cell cycle in human hepatocarcinoma Bel7402 cells. Possible molecular mechanisms were explored. METHODS： [3- （4, 5）-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide （MTT） assay, plasmid transfection, reporter assay, FACS and Western blotting analyses were employed to investigate the effect and the related molecular mechanisms of C2-ceramide on the cell cycle of Bel7402 cells. RESULTS： C2-ceramide was found to inhibit the growth of Bel7402 cells by indudng cell cycle arrest. During the process, the expression of p21 protein increased, while that of cyclinD1, phospho-ERKl/2 and c-myc decreased. Furthermore, the level of CDK7 was downregulated, while the transcriptional activity of PPARy was upregulated. Addition of GW9662, which is a PPARy specific antagonist, could reserve the modulation action on CDK7. CONCLUSION： Our results support the hypothesis that cell cycle arrest induced by C2-ceramide may be mediated via accumulation of p21 and reduction of cyclinD1 and CDK7, at least partly, through PPARy activation. The ERK signaling pathway was involved in this process.

关键词： Ceramide Cell cycle arrest Humanhepatocarcinoma cells P21 CyclinD1 CDK7 PPARy ERK

Semi-empirical and semi-quantitative lightweight shielding design method

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Nuclear Science and Techniques 2023年第3期34卷 109-124页

作者： song-Chuan Zheng Qing-Quan Pan Huan-Wen Lv song-Qian Tang xiao-jing Liu College of Smart Energy Shanghai Jiao Tong UniversityShanghai 200240China School of Nuclear Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610200China

The lightweight shielding design of small reactors is a popular research *** on a small helium-xenon-cooled solid reactor,the effects of neutron and photon shielding sequence and the number of shielding layers on the radiation dose were first *** was found that when photons were shielded first and the number of shielding layers was odd,the radiation dose could be significantly *** reduce the weight of the shielding body,the relative thickness of the shielding layers was optimized using the genetic *** optimized scheme can reduce the radiation dose by up to 57%and reduce the weight by 11.84%.To determine the total thickness of the shielding layers and avoid the local optimal solution of the genetic algorithm,a series of formulas that describes the relationship between the total thickness and the radiation dose was developed through large-scale calculations.A semi-empirical and semi-quantitative lightweight shielding design method is proposed to integrate the above shielding optimization method that verified by the Monte Carlo ***,a code,SDIC1.0,was developed to achieve the optimized lightweight shielding design for small *** was verified that the difference between the SDIC1.0 and the RMC code is approximately 10%and that the computation time is shortened by 6.3 times.

关键词： Small reactor Lightweight Shielding calculation Genetic algorithm

Synthesis, Structure and Electrochemistry of Macrocyclic 1,1'-Bis(1,3-phenyleneoxyacetylpyrazoyl)ferrocene

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Chinese Journal of Structural Chemistry 2007年第5期26卷 505-510页

作者： ZHU Mei-Jun song xiao-Kai SUN jing YAN Chao-Guo Department of Civil Engineering Jianghai Polytechnic College Yangzhou 225101 China College of Chemistry ＆ ChemiealEngineering Yangzhou University Yangzhou 225002 China

1,1＇-Diacetoacetylferrocene 1 reacted with phenylene-1,3-dioxyactyl hydrazine 2 in absolute ethanol to give the macrocyclic ferrocenyl dipyrazole compound in moderate yield. Determined by X-ray structure analysis, it crystallizes in monoclinic system, space group P21/c with a = 13.7509（4）, b = 8.1277（2）, c = 21.7472（6） A, β = 103.1030（10）°, V = 2367.25（11） A^3, Z = 4, Dc = 1.505 g/cm^3, R = 0.0353 and wR = 0.0811. The electrochemical studies reveal that redox of Fe^＋/Fe in ferrocene is a reversible one-electron process.

关键词： ferrocene acetylacetone pyrazole cyclic voltammetry

Clinical observation of vitrectomy combined with endolaser photocoagulation at the edge of posterior scleral staphyloma for macular hole retinal detachment in high myopia

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International Journal of Ophthalmology(English edition) 2022年第10期15卷 1650-1656页

作者： xiao-Tian Zhang jing-Xian Wang song Chen Clinical College of Ophthalmology Tianjin Medical UniversityTianjin 300020China Tianjin Eye Hospital Tianjin 300020China Tianjin Key Laboratory of Ophthalmology and Visual Science Tianjin300020China Tianjin Medical University Tianjin 300070China

AIM: To observe the clinical effect of pars plana vitrectomy(PPV) and silicone oil filling surgery combined with intraoperative posterior scleral staphyloma(PS) marginal retinal photocoagulation in the treatment of high myopic macular hole retinal detachment(MHRD) with ***: This was a retrospective clinical study. From May 2017 to March 2020, 62 MHRD patients with PS(62 eyes) were enrolled in the study. Patients were divided into 23 G PPV combined with PS marginal retina intraoperative photocoagulation group(combined group) and conventional surgery group(conventional group), with 31 eyes in each. Triamcinolone acetonide and indocyanine green were used to remove the epiretinal membrane and the posterior macular inner limiting membrane(ILM). In the combined group, 2 to 3 rows of retinal photocoagulation were performed on the edge of the PS. The patients were followed up for an average of 8.34±3.21 mo. The first retinal reattachment rate, macular hole closure rate, Duration of silicone oil tamponade, best corrected visual acuity(BCVA) and average number of operations were observed and compared between the two ***: The first retinal reattachment rates of the eyes in the combined group and the conventional group were 96.7%(29/31) and 67.7%(21/31), respectively(χ~2=6.613, P=0.010). The macular hole closure rates in the combined group and the conventional group were 74.2%(23/31) and 67.7%(21/31), respectively(χ~2=0.128, P=0.721). The Duration of silicone oil tamponade of the patients in the combined group was lower than that of the routine group(t=-41.962, P≤0.001). Postoperative log MAR BCVA values of patients in the combined group and the conventional group were 1.27±0.12 and 1.26±0.11, compared with the log MAR BCVA before surgery, each group was improved(t=19.947, t=-19.517, P≤0.001, P≤0.001). There was no significant difference in the log MAR BCVA between the eyes of the two groups(t=-0.394, P=0.695). The average numbers of operations on the eyes in

关键词： macular hole retinal detachment high myopia posterior scleral staphyloma retinal photocoagulation vitrectomy

Face Alignment by Coarse-to-Fine Shape Estimation

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Chinese Journal of Electronics 2018年第6期27卷 1183-1191页

作者： WAN Jun LI jing CHANG Jun WU Yujia xiao Yafu song Chengfang School of Computer Science Wuhan University

This paper presents a way to face alignment by Coarse-to-fine shape estimation(CFSE). Head poses, facial expressions and other facial appearance attributes are estimated coarsely as well as the main landmarks will be detected. The entire shape will be further estimated. This paper constructs an independent Head pose classification(HPC) model based on convolutional neural network to estimate and classify head poses. With the classification result, the estimated facial appearance attributes and the detected landmarks, a more accurate shape will be constructed. That shape will be used as the initialized shape and optimized by cascaded regression to approximate the ground-truth shape. Experiments on two challenging database demonstrate that CFSE outperforms the state-of-the-art methods.

关键词： Facial appearance attributes Head pose classification model Convolutional neural network Initialized shape Cascaded regression

Asymmetric radical allylation of β-keto esters with vinyl cyclopropanes by dual photoredox/nickel catalysis

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Science China Chemistry 2024年第11期67卷 3807-3816页

作者： Wen-Yuan Qu Xue-song Zhou Wen-jing xiao Jia-Rong Chen Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction Ministry of EducationCollege of ChemistryCentral China Normal UniversityWuhan 430079China Wuhan Institute of Photochemistry and Technology 7 North Bingang RoadWuhan 430083China Key Laboratory of Organo-Pharmaceutical Chemistry of Jiangxi Province Gannan Normal UniversityGanzhou 341000China

Radical-involved allylation reactions have emerged as a powerful platform for construction of carbon-carbon and carbonheteroatom bonds, facilitating the strategic incorporation of diverse allyl moieties. Nevertheless, this burgeoning field still faces ongoing challenges, including limitations of radical precursors and coupling partners, and difficulties in achieving enantiocontrol. Herein, we report for the first time a highly enantioselective radical allylation involving β-keto esters with vinyl cyclopropanes utilizing a synergistic dual photoredox/nickel catalysis under visible light irradiation. The mild and redox-neutral catalytic protocol demonstrates an extensive substrate compatibility and good functional tolerance, providing access to enantioenriched β-keto esters featuring quaternary α-stereocenter with good yields and high enantioselectivities. Preliminary mechanistic studies have uncovered that the success of the reaction hinges on the dual roles of nickel catalyst, including in situ formation of photoredox sensitive substrate/Ni complex and the ensuing asymmetric radical addition step.

关键词： asymmetric allylation photoredox catalysis radical addition nickel catalysis β-keto esters vinyl cyclopropanes

Interfacial phenomena of water striders on water surfaces: a review from biology to biomechanics

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Zoological Research 2020年第3期41卷 231-246页

作者： jing-Ze Ma Hong-Yu Lu xiao-song Li Yu Tian State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China

Water striders have intrigued researchers for centuries from the viewpoints of biology to biomechanics. In this review, we introduce the basic theories and techniques of physics and force measurement for biomechanical research into water striders. Morphological and behavioral traits of water striders are summarized and discussed from biomechanical perspectives, along with comparative study. This integrated review also highlights potential directions for studies on water-walking arthropods,which might inspire future biological and biomechanical research.

关键词： Water strider Water repellency Surface tension Surface propulsion

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白城松原电网存在问题及对策

吉林电力 2008年第3期36卷 43-46页

作者：王晓波宋景山孙振胜曲振军吉林省电力有限公司吉林长春130021

针对白城松原电网的现状,分析了电网存在的与主系统联系薄弱、部分一次变电站接线不满足电网发展要求及66 kV电源联络薄弱,对220 kV系统支撑不够的问题,提出了改变220 kV一次变母线接线方式、增加主变、加快66 kV联络线建设等相应的措施... 详细信息

针对白城松原电网的现状,分析了电网存在的与主系统联系薄弱、部分一次变电站接线不满足电网发展要求及66 kV电源联络薄弱,对220 kV系统支撑不够的问题,提出了改变220 kV一次变母线接线方式、增加主变、加快66 kV联络线建设等相应的措施,以及电网改造、建设方面的意见和建议。

关键词：白城松原电网电网改造电网规划