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Asian Journal of Andrology 2020年第6期22卷 547-548页

作者： Shu-Jie Liao yan-Ying Xu Rui-Juan Sun qun-yan lyu Department of Health Science National Natural Science Foundation of ChinaBeijing 100085China Department of Obstetrics and Gynecology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

"Reproductive health"was officially defined as humans and their individual activities related to reproduction throughout their lives,which should be in good health in physical,psychological,and social aspects.1 The basic research on male reproductive health in China can be traced back to the 1960s.2 Since the National Natural Science Foundation of China(NSFC)began systematic support for basic research on male reproductive health in 1988,the field has been systematically developed in *** this regard,we analyze the role of the NSFC on the development of basic research in the field of male reproductive health in China.

关键词： NSFC China. field

A NONMONOTONE SECOND-ORDER STEPLENGTH METHOD FOR UNCONSTRAINED MINIMIZATION

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Journal of Computational Mathematics 2007年第1期25卷 104-112页

作者： qun-yan Zhou Wen-yu Sun Department of Basic Science Jiangsu Teachers University of Technology Changzhou 213001 China School of Mathematics and Computer Science Nanjing Normal University Nanjin9 210097 China School of Mathematics and Computer Science Nanjing Normal University Nanjing 210097 China

In this paper, a nonmonotone method based on McCormick＇s second-order Armijo＇s step-size rule [7] for unconstrained optimization problems is proposed. Every limit point of the sequence generated by using this procedure is proved to be a stationary point with the second-order optimality conditions. Numerical tests on a set of standard test problems are presented and show that the new algorithm is efficient and robust.

关键词： Nonmonotone method Armijo's line search Direction of negative curvature,Unconstrained optimization.

AN ADAPTIVE NONMONOTONIC TRUST REGION METHOD WITH CURVILINEAR SEARCHES

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Journal of Computational Mathematics 2006年第6期24卷 761-770页

作者： qun-yan Zhou Wen-yu Sun School of Mathematics and Computer Science Nanjing Normal University Nanjing 210097 China Department of Mathematics Jiangsu Teacher University of Technology Changzhou 213001 China

In this paper, an algorithm for unconstrained optimization that employs both trust region techniques and curvilinear searches is proposed. At every iteration, we solve the trust region subproblem whose radius is generated adaptively only once. Nonmonotonic backtracking curvilinear searches are performed when the solution of the subproblem is unacceptable. The global convergence and fast local convergence rate of the proposed algorithms are established under some reasonable conditions. The results of numerical ＇experiments are reported to show the effectiveness of the proposed algorithms.

关键词： Unconstrained optimization Preconditioned gradient path Trust region method,Curvilinear search.

Dynamic response to a moving load of a Timoshenko beam resting on a nonlinear viscoelastic foundation

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Acta Mechanica Sinica 2013年第5期29卷 718-727页

作者： yan yang Hu Ding Li-qun Chen Shanghai Institute of Applied Mathematics and Mechanics Shanghai Key Laboratory of Mechanics in Energy EngineeringShanghai University Department of Mechanics Shanghai University

The present paper investigates the dynamic response of finite Timoshenko beams resting on a sixparameter foundation subjected to a moving load. It is for the first time that the Galerkin method and its convergence are studied for the response of a Timoshenko beam supported by a nonlinear foundation. The nonlinear Pasternak foundation is assumed to be cubic. Therefore, the effects of the shear deformable beams and the shear deformation of foundations are considered at the same time. The Galerkin method is utilized for discretizing the nonlinear partial dif- ferential governing equations of the forced vibration. The dynamic responses of Timoshenko beams are determined via the fourth-order Runge-Kutta method. Moreover, the effects of different truncation terms on the dynamic responses of a Timoshenko beam resting on a complex foundation are discussed. The numerical investigations shows that the dynamic response of Timoshenko beams supported by elastic foundations needs super high-order modes. Furthermore, the system parameters are compared to determine the dependence of the convergences of the Galerkin method.

关键词： Nonlinear Timoshenko beam Pasternak foun- dation Galerkin method Convergence

Self-Detection of Leaking Pipes by One-Dimensional Photonic Crystals

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Chinese Physics Letters 2012年第6期29卷 172-174页

作者： ZHOU yan YIN Li-qun Department of Physics Yanshan UniversityQinhuangdao 066004 Educational Administration Hebei Normal University of Science and TechnologyQinhuangdao 066004

We report a new self-detection control system for leaking pipes by making use of the surface defects of 1D photonic crystals,where the key concept is analog to the Bragg fiber *** current low costs and coating techniques of SiO2 are beneficial to the applications,and its error is below the standard *** problem of leaking pipes can be resolved by devising a remote pipeline control system which combines a long-distance pipeline and a signal transmission system.

关键词： fiber Crystal pipes

Analytical and Numerical Studies for Chaotic Dynamics of a Duffing Oscillator with a Parametric Force

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Communications in Theoretical Physics 2007年第3X期48卷 477-480页

作者： WANG yan-qun WU Qin Department of Mathematics Hengyang Normal University Hengyang 421008 China School of Basic Medical Science Guangdong Medical College Dongguan 523808 China

The chaotic dynamics of a Duffing oscillator with a parametric force is investigated. By using the direct perturbation technique, we analytically obtain the general solution of the lst-order equation. Through the boundedness condition of the general solution we get the famous Melnikov function predicting the onset of chaos. When the parametric and external forces are strong, numerical simulations show that increasing the amplitude of the parametric or external force can lead the system into chaos via period doubling.

关键词： general solution Melnikov function period doubling chaos

Effects of Micelle on Pyrazoles as Antioxidants in Radical-induced Oxidation of DNA

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Chemical Research in Chinese Universities 2013年第4期29卷 671-677页

作者： LI yan-feng LIU Zai-qun Department of Organic Chemistry College of Chemistry Jilin University Changchun 130021 P. R. China

Effects of 4-（1,3-diphenyl-1H-pyrazol-5-yl）phenol（APP）,4-（1,5-diphenyl-lH-pyrazol-3-yl）phenol（BPP） and 4-（3,5-diphenyl-1H-pyrazol-1-yl）phenol（CPP） on 2,2＇-azobis-（2-amidinopropane hydrochloride）（AAPH）-induced oxidation of DNA were measured in the presence of various concentrations of Triton X-100,cetyltrimethylammonium bromide（CTAB）,or sodium dodecyl sulfate（SDS） in order to clarify the influence of neutral,cationic and anionic microenvironments on antioxidant capacities of APP,BPP and *** these surfactants can protect DNA against AAPH-induced oxidation,the pyrazoles in the presence of these surfactants functioned as prooxidants when the concentrations of Triton X-100 and CTAB ***,CPP exhibited antioxidant property with the increase of the concentration of *** the contrary,APP,BPP and CPP were antioxidants in the presence of various concentrations of *** added surfactants resulted in the complication of the microenvironments around DNA,pyrazoles and peroxyl radical（ROO＊） derived from *** anionic charge of SDS was beneficial to enhancing the antioxidant effectiveness of these *** can be concluded that the charge property of surfactants markedly influenced the behavior of an antioxidant in AAPH-induced oxidation of DNA.

关键词： Pyrazole Surfactant Oxidation DNA Free radical Microenvironment effect

Hohmann transfer via constrained optimization

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Frontiers of Information Technology & Electronic Engineering 2018年第11期19卷 1444-1458页

作者： Li XIE Yi-qun ZHANG Jun-yan XU State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources School of Control and Computer EngineeringNorth China Electric Power UniversityBeijing 102206China Beijing Institute of Electronic Systems Engineering Beijing 100854China

Inspired by the geometric method proposed by Jean-Pierre MAREC, we first consider the Hohmann transfer problem between two coplanar circular orbits as a static nonlinear programming problem with an inequality constraint. By the Kuhn-Tucker theorem and a second-order sufficient condition for minima, we analytically prove the global minimum of the Hohmann transfer. Two sets of feasible solutions are found: one corresponding to the Hohmann transfer is the global minimum and the other is a local minimum. We next formulate the Hohmann transfer problem as boundary value problems, which are solved by the calculus of variations. The two sets of feasible solutions are also found by numerical examples. Via static and dynamic constrained optimizations, the solution to the Hohmann transfer problem is re-discovered, and its global minimum is analytically verified using nonlinear programming.

关键词： Hohmann transfer Nonlinear programming Constrained optimization Calculus of variations

Neonatal hemorrhage stroke and severe coagulopathy in a late preterm infant after receiving umbilical cord milking:A case report

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World Journal of Clinical Cases 2022年第16期10卷 5365-5372页

作者： yan Lu Zhi-qun Zhang Department of Neonatology Affiliated Hangzhou First People’s HospitalZhejiang University School of MedicineHangzhou 310003Zhejiang ProvinceChina

BACKGROUND Umbilical cord milking(UCM)is an alternative placental transfusion method for delayed umbilical cord clamping in routine obstetric practice,allowing prompt resuscitation of an ***,UCM has been adopted at some tertiary neonatal centers for preterm infants to enhance placental-to-fetal *** is not suggested for babies less than 28 wk of gestational age because it is associated with severe brain *** late preterm or term infants who do not require resuscitation,cord management is recommended to increase iron levels and prevent the development of iron deficiency anemia,which is associated with impaired motor development,behavioral problems,and cognitive *** remain about whether UCM increases the incidence of intraventricular ***,there are very few reports of late preterm infants presenting with neonatal hemorrhage stroke(NHS)and severe coagulopathy after receiving ***,we report a case of a late preterm infant born at 34 wk of *** abruptly deteriorated,exhibiting signs and symptoms of NHS and severe coagulopathy after receiving UCM on the first day of *** SUMMARY A female preterm infant born at 34 wk of gestation received UCM after *** was small for her gestational age and described as vigorous with Apgar scores of 9 and 10 at one minute and five minutes of life,*** hospitalization in the neonatal intensive care unit,she showed hypoglycemia and metabolic *** baby was administered glucose and sodium bicarbonate *** vitamin K1 was also used to prevent vitamin K *** baby developed umbilical cord bleeding and gastric bleeding on day 1 of life;a physical examination showed bilateral conjunctival hemorrhage,and a blood test showed thrombocytopenia,prolonged prothrombin time,prolonged activated partial thromboplastin time,low fibrinogen,raised D-dimer levels and anemia.A subsequent cranial ultrasound and computed tomography scan sho

关键词： Neonatal hemorrhage stroke Umbilical cord milking Coagulopathy Disseminated intravascular coagulation Premature infant Small for gestational age Case report

Shu-szi Sin: A Chinese pioneer biologist, ancient agronomist, and educator

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Protein & Cell 2021年第7期12卷 515-517页

作者： qun Xie yan-ping Cheng Lei Fu Teacher Education College Zhejiang Normal UniversityJinhua 321000China

Shu-szi Sin(辛树枳,1894-1977)(Fig.1),a Chinese pioneer biologist and ancient agronomist,initiated the earliest scientific biological investigation of the Dayao mountain in both Guangxi and Guangdong provinces,discovering more than 20 new species that have been acknowledged *** was one of the founders and initiators of the China Botanical Society and the China Zoological *** was also a great educator Among one of those who first introduced the scientific method into agricultural history research,*** helped to set up the National Northwest Agriculture and Forestry College(now Northwest A&F University)and the Lanzhou *** devoted himself to the development of higher education in Northwest China.

关键词： China. Northwest devoted