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Atrial fibrillation and dementia: not just a coincidence
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作者 Udit Choubey Vasu Bansal +5 位作者 Priyanshi Shah FNU Anamika Vasu Gupta Sweta Sahu Miran Rezhan Rohit Jain 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2023年第9期697-701,共5页
Atrial fibrillation(AF)is the most common form of cardiac arrhythmia,affecting 3 to 6 million people in the US,with an increased incidence in women and elderly,with its prevalence estimated to increase from 5.1 millio... Atrial fibrillation(AF)is the most common form of cardiac arrhythmia,affecting 3 to 6 million people in the US,with an increased incidence in women and elderly,with its prevalence estimated to increase from 5.1 million in 2000 to 15.9 million in 2050 in the US population.[1]Age,hypertension,heart failure,myocardial infarction(MI),genetic factors,and associated systemic inflammatory states are well-established risk factors for the development of AF.[2–6]Lifestyle factors including alcohol consumption,smoking,obesity,sedentary lifestyle,and vigorous physical activity have also been implicated to contribute to the development of AF.[2,7–9]Studies suggest that AF drives up medical expenditure.[10]The European Society of Cardiology,based on the duration,responsiveness to treatment,and therapeutic attitude of the patient and physician,classifies AF into 4 types;when AF occurs and terminates by itself or by intervention within 7 days of onset,it is called paroxysmal AF;if sustained for more than a week,with or without intervention. 展开更多
关键词 SUSTAINED FIBRILLATION COINCIDENCE
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Impact of random and scattered coincidences from outside of field of view on positron emission tomography/computed tomography imaging with different reconstruction protocols
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作者 Mahak Osouli Alamdari Pardis Ghafarian +2 位作者 Arman Rahmim Mehrdad Bakhshayesh‑Karam Mohammad Reza Ay 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第12期40-52,共13页
Image quality in positron emission tomography(PET)is affected by random and scattered coincidences and reconstruction protocols.In this study,we investigated the effects of scattered and random coincidences from outsi... Image quality in positron emission tomography(PET)is affected by random and scattered coincidences and reconstruction protocols.In this study,we investigated the effects of scattered and random coincidences from outside the field of view(FOV)on PET image quality for different reconstruction protocols.Imaging was performed on the Discovery 690 PET/CT scanner,using experimental configurations including the NEMA phantom(a body phantom,with six spheres of different sizes)with a signal background ratio of 4:1.The NEMA phantom(phantom I)was scanned separately in a one-bed position.To simulate the effect of random and scatter coincidences from outside the FOV,six cylindrical phantoms with various diameters were added to the NEMA phantom(phantom II).The 18 emission datasets with mean intervals of 15 min were acquired(3 min/scan).The emission data were reconstructed using different techniques.The image quality parameters were evaluated by both phantoms.Variations in the signal-to-noise ratio(SNR)in a 28-mm(10-mm)sphere of phantom II were 37.9%(86.5%)for ordered-subset expectation maximization(OSEM-only),36.8%(81.5%)for point spread function(PSF),32.7%(80.7%)for time of flight(TOF),and 31.5%(77.8%)for OSEM+PSF+TOF,respectively,indicating that OSEM+PSF+TOF reconstruction had the lowest noise levels and lowest coefficient of variation(COV)values.Random and scatter coincidences from outside the FOV induced lower SNR,lower contrast,and higher COV values,indicating image deterioration and significantly impacting smaller sphere sizes.Amongst reconstruction protocols,OSEM+PSF+TOF and OSEM+PSF showed higher contrast values for sphere sizes of 22,28,and 37 mm and higher contrast recovery coefficient values for smaller sphere sizes of 10 and 13 mm. 展开更多
关键词 Positron emission tomography/computed tomography(PET/CT) Random coincidences Scatter coincidences·Time of flight(TOF) Point spread function(PSF) Field of view(FOV) Noise equivalent count rate(NECR) Signal-toNoise ratio(SNR)
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Hypothyroidism and non-alcoholic fatty liver disease:A coincidence or a causal relationship?
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作者 Barbara Janota Elżbieta Szczepańska +1 位作者 Brygida Adamek Ewa Janczewska 《World Journal of Hepatology》 2023年第5期641-648,共8页
Non-alcoholic fatty liver disease(NAFLD)is a global problem.It may be caused by metabolic and hormonal disorders,including hypothyroidism.However,non-thyroid causes of NAFLD in people with hypothyroidism,including imp... Non-alcoholic fatty liver disease(NAFLD)is a global problem.It may be caused by metabolic and hormonal disorders,including hypothyroidism.However,non-thyroid causes of NAFLD in people with hypothyroidism,including improper eating behavior and low physical activity,should be acknowledged.This study aimed to present the current literature on whether the development of NAFLD is related to hypothyroidism or a typical consequence of an unhealthy lifestyle in people with hypothyroidism.The results of previous studies do not allow for an unequivocal determination of the pathogenetic relationship between hypothyroidism and NAFLD.Important non-thyroid-initiating factors include providing too many calories in relation to requirements,consuming excessive amounts of monosaccharides and saturated fats,being overweight,and maintaining low physical activity levels.The recommended nutritional model for both hypothyroidism and NAFLD may be the Mediterranean diet,which is rich in fruits and vegetables,polyunsaturated fatty acids,and vitamin E. 展开更多
关键词 VITAMIN COINCIDENCE consuming
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Texture Analysis of Damascene Copper Interconnects 被引量:2
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作者 王晓冬 吉元 +4 位作者 钟涛兴 李志国 夏洋 刘丹敏 肖卫强 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第6期1136-1140,共5页
Texture and grain boundary character distribution of Cu interconnects with different line width for as-deposited and annealed conditions were measured by EBSD. All specimens appear mixed texture and (111) texture is... Texture and grain boundary character distribution of Cu interconnects with different line width for as-deposited and annealed conditions were measured by EBSD. All specimens appear mixed texture and (111) texture is the dominate component.As-deposited interconnects undergo the phenomenon of self-annealing at RT,in which some abnormally large grains are found. Lower aspect ratio of lines and anneal treatment procured larger grains and stronger (111) texture. Meanwhile, the intensity proportion of other textures with lower strain energy to (111) texture is decreased. As-deposited specimens reveal (111)(112? and (111) (231) components, (111) (110) component appeared and (111) (112? and (111) (231) components were developed during the annealing process. High angle boundaries are dominant in all specimens, boundaries with a misorientation of 55°-60° and ∑3 ones in higher proportion, followed by lower boundaries with a misorientation of 35°-40° and 29 boundaries. As the aspect ratio of lines and anneal treatment increase,there is a gradual in- crement in ∑3 boundaries and a decrease in ∑9 boundaries. 展开更多
关键词 Cu interconnects TEXTURE MISORIENTATION coincident site lattice boundaries EBSD
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从语义学角度看英汉医学词汇的理解与翻译 被引量:3
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作者 李定钧 《上海翻译》 CSSCI 北大核心 1999年第3期22-24,共3页
符号学理论认为语言符号存在三种对应关系——语义关系、语用关系和语形关系。语义关系指的是符号与它所指称的外在事物之间的关系,实质上就是指称关系;语用关系指的是符号与符号使用者之间的关系;语形关系指的是符号与符号之间的关... 符号学理论认为语言符号存在三种对应关系——语义关系、语用关系和语形关系。语义关系指的是符号与它所指称的外在事物之间的关系,实质上就是指称关系;语用关系指的是符号与符号使用者之间的关系;语形关系指的是符号与符号之间的关系。对应于这三种关系存在着三类意义... 展开更多
关键词 SEMIOTICS REGISTER SEMANTIC COINCIDENCE SEMANTIC diversity
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Effect of Silicon-on-Insulator Substrate on Residual Strain in 3C-SiC Films
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作者 王晓峰 黄风义 +5 位作者 孙国胜 王雷 赵万顺 曾一平 李海鸥 段晓峰 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第9期1681-1687,共7页
One group of SiC films are grown on silicon-on-insulator (SOI) substrates with a series of silicon-overlayer thickness. Raman scattering spectroscopy measurement clearly indicates that a systematic trend of residual... One group of SiC films are grown on silicon-on-insulator (SOI) substrates with a series of silicon-overlayer thickness. Raman scattering spectroscopy measurement clearly indicates that a systematic trend of residual stress reduction as the silicon over-layer thickness decreases for the SOI substrates. Strain relaxation in the SiC epilayer is explained by force balance approach and near coincidence lattice model. 展开更多
关键词 RAMAN strain relaxation force balance principle near coincidence lattice model
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Existence of Periodic Solutions for Generalized Liénard-Typed Functional Differential Equations
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作者 贺小明 葛渭高 单文锐 《Journal of Beijing Institute of Technology》 EI CAS 2002年第3期325-328,共4页
The existence of periodic solutions for a kind of generalized Liénard typed functional differential equation is studied. By means of the continuation theorem of coincidence degree theory, existence criteria are ... The existence of periodic solutions for a kind of generalized Liénard typed functional differential equation is studied. By means of the continuation theorem of coincidence degree theory, existence criteria are established for the existence of periodic solutions and some previous results are extended. 展开更多
关键词 functional differential equation periodic solution coincidence degree
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四阶非线性方程周期解的存在性
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作者 杨作东 王元 柴新宽 《云南工业大学学报》 1990年第Z1期68-72,共5页
在本文中,我们证明了下列方程:{x^(4)(t)-n^4x(t)+g(t、x(t)、x′(t))=p(t) x(0)=x(2π),x′(0)=x′(2π),x″(0)=x″(2π),x^(3)(0)=x^(3)(2π)至少存在一个非零解,n为自然数。
关键词 FREDHOLM算子 L—紧 coincidence度
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集值Coincidence度及其应用
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作者 王志华 杨国为 《烟台师范学院学报(自然科学版)》 1994年第1期28-32,共5页
基于集值映象的Coincidence度理论,研究了一类算子包含问题的可解性,得到了锥拉压不动点定理的一个推广形式。
关键词 COINCIDENCE 集值映象 拓扑度
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Threshold Photoelectron-photoion Coincidence Imaging of Dissociation Dynamic of NO+ at c3∏(v′=0) State 被引量:1
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作者 孙金大 单晓斌 +6 位作者 刘付轶 盛六四 唐小锋 牛铭理 宋磊 周晓国 刘世林 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第5期509-512,621,共5页
The photodissociation of NO+ at c3∏(v′=0) state is studied by threshold photoelectron- photoion coincidence imaging method. By some assumptions, the relations between velocity in center of mass (CM) coordinates... The photodissociation of NO+ at c3∏(v′=0) state is studied by threshold photoelectron- photoion coincidence imaging method. By some assumptions, the relations between velocity in center of mass (CM) coordinates and most probable center of mass (MPCM) coordinates, time of flight and displacement in the velocity map image of fragment ions are derived using vector addition of velocity and displacement on the condition of perpendicular molecular beam. Using these relations the velocity in CM coordinates, the velocity and angular distri- bution of N+ fragment ions in MPCM coordinates are obtained and discussed, respectively. 展开更多
关键词 Threshold photoelectron-photoion coincidence imaging Velocity map imag-ing Nitric oxide Kinetic energy released distribution Angular distribution
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集值Coincidence度及其应用
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作者 谢胜利 《淮北煤师院学报(自然科学版)》 1995年第2期19-25,共7页
对于组合算子包含问题,在L是零指标的Fredholm算子的条件下,本文基于集值映射的广义度,建立了集值Coincidence拓扑度,并将所得结果应用于集值映射不动点的存在性,推广了已有的结果。
关键词 Coincidence度 不动点 拓扑度 集值映射
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A super-high resolution frequency standard measuring approach based on phase coincidence characteristics between signals 被引量:13
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作者 李智奇 周渭 +1 位作者 陈发喜 刘晨光 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第9期287-290,共4页
A method for super high resolution comparison measurement is proposed in this paper with a comparison between the frequency standards of different nominal frequencies, which is based on phase coincidence detection of ... A method for super high resolution comparison measurement is proposed in this paper with a comparison between the frequency standards of different nominal frequencies, which is based on phase coincidence detection of the two compared signals. It utilizes the regular phase shift characteristics between the signals. The resolution of the measurement approach can reach 10^-13/s at 5 MHz, and the self-calibration resolution can achieve 10^-14/s in the comparison between 10 MHz and 100 MHz, or even can reach 10^-15/s in the comparison between 10 MHz and 190 MHz. This method implies significant progress in the development of the high precision frequency standard comparison technology. 展开更多
关键词 frequency measurement RESOLUTION phase coincidence equivalent phase comparison frequency
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KKM TYPE THEOREMS AND COINCIDENCE THEOREMS ON L-CONVEX SPACES 被引量:13
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作者 丁协平 《Acta Mathematica Scientia》 SCIE CSCD 2002年第3期419-426,共8页
Some KKM theorems and coincidence theorems involving admissible set-valued mappings and the set-valued mappings with compactly local intersection property are proved in L-convex: spaces. As applications, some new fixe... Some KKM theorems and coincidence theorems involving admissible set-valued mappings and the set-valued mappings with compactly local intersection property are proved in L-convex: spaces. As applications, some new fixed point theorems are obtained in L-convex spaces. These theorems improve and generalize many important known results in recent literature. 展开更多
关键词 KKM type theorem coincidence theorem L-convex space
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EXISTENCE OF POSITIVE SOLUTION FOR A TWO-PATCHES COMPETITION SYSTEM WITH DIFFUSION AND TIME DELAY AND FUNCTIONAL RESPONSE 被引量:12
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作者 LiBiwen ZengXianwu 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2003年第1期1-8,共8页
By using the continuation theorem of coincidence theory, the existence of a positive periodic solution for a two patches competition system with diffusion and time delay and functional responsex [FK(W1*3/4。*2/3]... By using the continuation theorem of coincidence theory, the existence of a positive periodic solution for a two patches competition system with diffusion and time delay and functional responsex [FK(W1*3/4。*2/3]′ 1 (t)=x 1(t)a 1(t)-b 1(t)x 1(t)-c 1(t)y(t)1+m(t)x 1(t)+D 1(t)[x 2(t)-x 1(t)], x [FK(W1*3/4。*2/3]′ 2 (t)=x 2(t)a 2(t)-b 2(t)x 2(t)-c 2(t)∫ 0 -τ k(s)x 2(t+s) d s+D 2(t)[x 1(t)-x 2(t)], y′(t)=y(t)a 3(t)-b 3(t)y(t)-c 3(t)x 1(t)1+m(t)x 1(t)is established, where a i(t),b i(t),c i(t)(i=1,2,3),m(t) and D i(t)(i=1,2) are all positive periodic continuous functions with period w >0, τ is a nonnegative constant and k(s) is a continuous nonnegative function on [- τ ,0]. 展开更多
关键词 periodic solutions competition diffusive system functional response continuation theorem of coincidence degree topological degree.
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Intrinsic background radiation of LaBr3(Ce)detector via coincidence measurements and simulations 被引量:11
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作者 Hao Cheng Bao-Hua Sun +5 位作者 Li-Hua Zhu Tian-Xiao Li Guang-Shuai Li Cong-Bo Li Xiao-Guang Wu Yun Zheng 《Nuclear Science and Techniques》 SCIE CAS CSCD 2020年第10期33-42,共10页
The LaBr3(Ce)detector has attracted much attention in recent years because of its superior characteristics compared with other scintillating materials in terms of resolution and efficiency.However,it has a relatively ... The LaBr3(Ce)detector has attracted much attention in recent years because of its superior characteristics compared with other scintillating materials in terms of resolution and efficiency.However,it has a relatively high intrinsic background radiation because of the naturally occurring radioisotopes in lanthanum,actinium,and their daughter nuclei.This limits its applications in low-counting rate experiments.In this study,we identified the radioactive isotopes in theφ3"x 3"Saint-Gobain B380 detector by a coincidence measurement using a Clover detector in a low-background shielding system.Moreover,we carried out a Geant4 simulation of the experimental spectra to evaluate the activities of the main internal radiation components.The total activity of the background radiation of B380 is determined to be 1.523(34)Bq/cm^3.The main sources include 138La at 1.428(34)Bq/cm^3,207Tl at 0.0135(13)Bq/cm^3,211Bi at 0.0136(15)Bq/cm^3,215Po at 0.0135(3)Bq/cm^3,219Rn at 0.0125(12)Bq/cm^3,223Fr at 0.0019(11)Bq/cm^3,223Ra at 0.0127(10)Bq/cm^3,227Th at 0.0158(22)Bq/cm^3,and 227Ac at 0.0135(13)Bq/cm^3.Of these,the activities of 207Tl,211Po,215Po,223Fr,and 227Ac are deduced for the first time from the secular equilibrium established in the decay chain of 227Ac. 展开更多
关键词 LaBr3 Coincidence measurement technique Intrinsic radiation GEANT4 simulation
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New Unique Common Fixed Point Results for Four Mappings with Ф-Contractive Type in 2-Metric Spaces 被引量:14
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作者 Yongjie Piao Yuanfeng Jin 《Applied Mathematics》 2012年第7期734-737,共4页
In this paper, some new unique common fixed points for four mappings satisfying Ф-contractive conditions on non-complete 2-metric spaces are obtained, in which the mappings do not satisfy continuity and commutation. ... In this paper, some new unique common fixed points for four mappings satisfying Ф-contractive conditions on non-complete 2-metric spaces are obtained, in which the mappings do not satisfy continuity and commutation. The main results generalize and improve many well-known and corresponding conclusions in the literatures. 展开更多
关键词 2-Metric Space Class Ф CAUCHY Sequence COINCIDENCE POINT UNIQUE Common Fixed POINT
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Multiple gastrointestinal stromal tumors and bilateral pheochromocytoma in neurofibromatosis 被引量:4
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作者 Klaus Kramer Cornelia Hasel +2 位作者 Andrik J Aschoff Doris Henne-Bruns Peter Wuerl 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第24期3384-3387,共4页
The coincidence of a gastrointestinal stromal tumor (GIST) and a neuroendocrine tumor (NET) in neurofibromatosis type 1 (NF1) is described only five times within the literature. We report on a 63 year old Caucasian fe... The coincidence of a gastrointestinal stromal tumor (GIST) and a neuroendocrine tumor (NET) in neurofibromatosis type 1 (NF1) is described only five times within the literature. We report on a 63 year old Caucasian female with the rare condition of neurofibromatosis type 1 coinciding with recurrent gastrointestinal stromal tumor plus bilateral pheochromocytoma (PCC). After a history of palpitations and dizziness that lasted for years, a left adrenal mass was detected by CT. Laparotomy revealed a pheochromocytoma of the left adrenal gland while an ileoterminal GIST was found incidentally intraoperatively. After six months contralateral PCC and multiple recurrent GIST were resected again. After four years the patient is doing well without any signs of further recurrent tumors. Discussion includes review of the literature. 展开更多
关键词 Gastrointestinal stromal tumor Neuroendocrine tumor NEUROFIBROMATOSIS PHEOCHROMOCYTOMA COINCIDENCE
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THE COLLOCATION METHODS FOR SINGULAR INTEGRAL EQUATIONS WITH CAUCHY KERNELS 被引量:5
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作者 杜金元 《Acta Mathematica Scientia》 SCIE CSCD 2000年第3期289-302,共14页
This paper applies the singular integral operators, singular quadrature operators and discretization matrices associated with singular integral equations with Cauchy kernels, which are established in [1], to give a un... This paper applies the singular integral operators, singular quadrature operators and discretization matrices associated with singular integral equations with Cauchy kernels, which are established in [1], to give a unified framework for various collocation methods of numerical solutions of singular integral equations with Cauchy kernels. Under the framework, the coincidence of the direct quadrature method and the indirect quadrature method is very simple and obvious. 展开更多
关键词 direct collocation methods indirect collocation methods coincidence technique
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Existence of two periodic solutions of a ratio-dependent Holling-Taner model with infinite delay and prey harvest 被引量:5
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作者 TIAN De-sheng 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第2期136-142,共7页
This paper considers a class of ratio-dependent Holling-Taner model with infinite delay and prey harvest, which is of periodic coefficients. By means of the coincidence degree theory, a set of sufficient conditions fo... This paper considers a class of ratio-dependent Holling-Taner model with infinite delay and prey harvest, which is of periodic coefficients. By means of the coincidence degree theory, a set of sufficient conditions for the existence of at least two positive periodic solutions of this model is established. 展开更多
关键词 Holling-Taner model RATIO-DEPENDENT HARVEST periodic solution coincidence degree.
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Periodic Solution for Diffusive Predator-Prey System with Functional Response 被引量:4
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作者 Li Bi\|wen 1,2 , Cheng Jian 1 1. Department of Mathematics, Hubei Normal University, Huangshi 435002, Hubei,China 2. School of Mathematics and Statistics, Wuhan University, Wuhan 430072, Hubei,China 《Wuhan University Journal of Natural Sciences》 CAS 2002年第3期267-273,共7页
In this paper, a three species diffusive predator-prey model with functional response is studied, where all parameters are time dependent. By using the continuation theorem of coincidence degree theory, the existence ... In this paper, a three species diffusive predator-prey model with functional response is studied, where all parameters are time dependent. By using the continuation theorem of coincidence degree theory, the existence of a positive periodic solution for this system is established. 展开更多
关键词 diffusive model functional nesponse positive periodic solution continuation theorem of coincidence degree fopological degree
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