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Persistence and periodic measure of a stochastic predator-prey model with Beddington-DeAngelis functional response

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生物数学学报:英文版 2023年第6期16卷 175-207页

作者： Jiangtao Yang School of Mathematics and Statistics Yangtze Normal UniversityChongqing408100P.R.China

In this paper,we study a stochastic predator-prey model with Beddington-DeAngelis functional response and time-periodic coefficients.By analyzing the stability of the solution on the boundary and some stochastic estimates,the threshold conditions for the time-average Persistence in probability and extinction of each population are established.Furthermore,the existence of a unique periodic measure of the model is also presented under the condition of the time-average Persistence in probability of the model.Several numerical simulations are given to verify the effectiveness of the theoretical results and to illustrate the effects of the white noises on the Persistence and periodic measure of the model.

关键词： Predator-prey model stochastic perturbation Persistence extinction periodic measure

Study on Transfer and Persistence of Fibers:A Systematic Review

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Journal of Forensic Science and Medicine 2022年第2期8卷 68-75页

作者： Manashree Mane Devika Gz Assistant Professor Department of Forensic ScienceJAIN(Deemed-to-be University)BangaloreKarnatakaIndia BSc Student Department of Forensic ScienceJAIN(Deemed-to-be University)BangaloreKarnatakaIndia

Fiber evidence has played a crucial role in ascertaining various characteristics and has aided in providing evidential value to the fiber evidence as well as reconstructing events during crime scene investigation.Although fibers are transferred easily at the crime scene and various methods of interpretation exist,it is challenging to get a fiber match.The present study aims to provide a systematic review of the role of fiber as trace evidence.It explores the fiber population,transfer and Persistence of fibers,fiber shedability and recovery,effect of laundry on fibers,stabbing events,the resistance of fabric against weapon's penetration,the behavior of fabric upon ballistic impact,and various analytical techniques of fiber examination.The study approaches to evaluate the significances and uncertainties of the recovered fiber evidence.

关键词： Damaged fabrics fiber evidence Persistence transfer

Persistence and extinction of Markov switched stochastic Nicholson’s blowflies delayed differential equation

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International Journal of Biomathematics 2020年第3期13卷 29-35页

作者： Wentao Wang Wei Chen School of Mathematics Physics and Statistics Shanghai University of Engineering Science Shanghai 201620P.R.China School of Statistics and Mathematics Shanghai Lixin University of Accounting and Finance Shanghai 201209 P.R.China

In this paper,we study the Persistence and extinction of Markov switched stochastic Nicholson's blowflies delayed differential equation.We derive sufficient conditions of Persistence and extinction for blowflies popul... 详细信息

关键词： Nicholson's blowflies model Persistence extinction Markov switched.

Blastocystis incidence, spontaneous clearance, Persistence and risk factors in a rural community in Thailand: A prospective cohort study

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Asian Pacific Journal of Tropical Medicine 2020年第3期13卷 123-130页

作者： Kawin Wongthamarin Thanaporn Trairattanapa Sirakit Kijanukul Thanakrit Kritsilpe Sarun Poobunjirdkul Warit Chuengdee Mathirut Mungthin Saovanee Leelayoova Tawee Naaglor Paanjit Taamasri PichaSuwannahitatorn Toon Ruang-Areerate Phunlerd Piyaraj Phramongkutklao College of Medicine Bangkok 10400Thailand Department of Parasitology Phramongkutklao College of MedicineBangkok 10400Thailand

Objective: To investigate the incidence, spontaneous clearance, Persistence and risk factors of Blastocystis infection in a rural community in Thailand.Methods: In February 2016, a cohort study was conducted in a rural community of Thailand. Baseline information of intestinal parasitic infections and follow-up visits were conducted. Blastocystis infection was detected in stool samples examined with short-term in vitro cultivation using Jones’ medium supplemented with 10% horse serum. Participants were tested for Blastocystis infection at every study visit. Cox proportional hazard regression analysis was used to evaluate co-variates to determine the incidence of Blastocystis infection. Results: Of 733 enrolled participants, 57(7.78%) were positive and 676(92.22%) were negative for Blastocystis infection. All 676 participants were followed-up for Blastocystis infection between December 2016 and January 2018. In all, 52 of 482 cases(10.79%) comprised individual Blastocystis infection. The incidence density rates of Blastocystis infection, of spontaneous clearance of the disease and of persistent infection were 8.13, 63.14 and 38.70 per 1 000 person-months of follow-up, respectively. Our multivariate analysis revealed that opened defecation in fields or bushes(HR=4.8;95% CI=2.1-10.4, P<0.001), raising cows(HR=2.8;95% CI=1.1-7.1, P=0.032), not washing hands after animal contact(HR=2.1;95% CI=1.0-4.2, P=0.044) and presenting symptoms of nausea or vomiting(HR=2.3;95% CI=1.0-5.3, P=0.047) were predictive associated risks for the incidence of Blastocystis infection. Conclusions: Our study indicates that the best way to prevent Blastocystis infection can be by maintaining good personal hygiene, hand washing after animal contact and improving sanitary facilities.

关键词： Blastocystis Incidence Spontaneous clearance Persistence Risk factors Thailand

Persistence AND THE GLOBAL DYNAMICS OF THE POSITIVE SOLUTIONS FOR A RATIODEPENDENT PREDATOR-PREY SYSTEM WITH A CROWDING TERM IN THE PREY EQUATION

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Acta Mathematica Scientia 2016年第3期36卷 689-703页

作者：曾宪忠顾永耕 School of Mathematics and Computing Science Hunan University of Science and Technology Department of Mathematics Hunan Normal University

This paper deals with the global dynamical behaviors of the positive solutions for a parabolic type ratio-dependent predator-prey system with a crowding term in the prey equation, where it is assumed that the coefficient of the functional response is less than the coefficient of the intrinsic growth rates of the prey species. We demonstrated some special dynamical behaviors of the positive solutions of this system which the Persistence of the coexistence of two species can be obtained when the crowding region in the prey equation only is designed suitably. Furthermore, we can obtain that under some conditions, the unique positive steady state solution of the system is globally asymptotically stable.

关键词： ratio-dependent predator-prey system crowding effect Persistence global stability

THE Persistence OF SOLUTIONS IN A NONLOCAL PREDATOR-PREY SYSTEM WITH A SHIFTING HABITAT

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Acta Mathematica Scientia 2024年第3期44卷 1096-1114页

作者：赵敏袁荣 School of Science Tianjin Chengjian University Laboratory of Mathematics and Complex Systems (Ministry of Education) School of Mathematical SciencesBeijing Normal University

In this paper,we mainly study the propagation properties of a nonlocal dispersal predator-prey system in a shifting environment.It is known that Choi et al.[J Differ Equ,2021,302:807-853] studied the Persistence or extinction of the prey and of the predator separately in various moving frames.In particular,they achieved a complete picture in the local diffusion case.However,the question of the Persistence of the prey and of the predator in some intermediate moving frames in the nonlocal diffusion case was left open in Choi et al.’s paper.By using some a prior estimates,the Arzelà-Ascoli theorem and a diagonal extraction process,we can extend and improve the main results of Choi et al.to achieve a complete picture in the nonlocal diffusion case.

关键词： predator-prey system Persistence nonlocal dispersal shifting environment 35K57 35K55 35B40 92D25

Persistence AND EXTINCTION OF A STOCHASTIC LOGISTIC MODEL WITH DELAYS AND IMPULSIVE PERTURBATION

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Acta Mathematica Scientia 2014年第5期34卷 1551-1570页

作者：卢春丁效华 Department of Mathematics Harbin Institute of Technology Department of Mathematics Qingdao Technological University

A stochastic logistic model with delays and impulsive perturbation is proposed and investigated. Sufficient conditions for extinction are established as well as nonPersistence in the mean, weak Persistence and stochastic permanence. The threshold between weak Persistence and extinction is obtained. Furthermore, the theoretical analysis results are also derivated with the help of numerical simulations.

关键词： logistic model white noise delay Persistence impulsive perturbation

Persistence and growth of faecal culturable bacterial indicators in water column and sediments of Vidy Bay,Lake Geneva,Switzerland

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Journal of Environmental Sciences 2009年第1期21卷 62-69页

作者： POTE John HALLER Laurence KOTTELAT Régis SASTRE Vincent ARPAGAUS Philippe WILDI Walter University of Geneva F.-A. Forel Institute10 route de Suisse1290 VersoixSwitzerland

The aims of this study was to investigate the Persistence and the growth of culturable bacterial indicators （CBI） including total coliforms （TC） and faecal coliforms represented by Escherichia coli, enterococcus （ENT）, and aerobic mesophilic bacteria （AMB） in the surface sediments and the water column of Vidy Bay fLake Geneva, City of Lausanne, Switzerland）. The study was carded out for 60 d using microcosms containing Sewage Treatment Plant （STP） effluent and nonsterile water without CBI, as well as contaminated and non-contaminated sediments. The effects of water temperature and of organic matter associated with sediments on the survival of CBI in the sediments and the water column were observed. The number of CBI colonies in the contaminated sediments of Vidy Bay and in the STP effluent was almost identical in the order of 10^5-10^7, 10^4-10^6, 10^5-10^5, and 10^4-10^7 CFU/100 g sediment or/100 mL water for TC, E. coli, ENT, and AMB respectively. A degradation of CBI was observed in the sediments where organic mater content was low and in the water column at a temperature of 10℃ after 5 d of experimentation. In addition, a growth of CBI was observed in the sediment which is rich in organic matter at 20℃. The results of this study indicate：（1） the higher concentrations of the CBI observed in different points in the water column of Vidy Bay may not be explained only by the recent contribution of the three potential sources of the Bay contamination including STP and the Chamberonne and Flon Rivers, but also by the Persistence, removal from sediment and multiplication of CBI in the sediment and water column; （2） the sediment of Vidy Bay constitute a reservoir of CBI and can even support their growth; and （3） the CBI not only survive in sediments, but also can be remobilized and increased in the water column, therefore, it become a permanent microbiological pollution in Vidy Bay.

关键词： Lake Geneva faecal pollution Persistence multiplication human health risk

Transjugular intrahepatic portosystemic shunt with accidental diagnosis of Persistence of the left superior vena cava

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World Journal of Gastroenterology 2010年第9期16卷 1158-1160页

作者： Ioannis Petridis Roberto Miraglia Gianluca Marrone Salvatore Gruttadauria Angelo Luca Giovanni Battista Vizzini Bruno Gridelli Department of Gastroenterology and Hepatology Mediterranean Institute for Transplantation and Advanced Specialized Therapies (IsMeTT)University of Pittsburgh Medical Center Department of Diagnostic and Interventional Radiology Mediterranean Institute for Transplantation and Advanced Specialized Therapies (IsMeTT)University of Pittsburgh Medical Center Department of Abdominal Surgery and Organ Transplantation Mediterranean Institute for Transplantation and Advanced Specialized Therapies (IsMeTT)University of Pittsburgh Medical Center

Transjugular intrahepatic portosystemic shunt (TIPSS) is considered a valid therapeutic option for the treatment of portal hypertension and its complications.The guidelines for this procedure have already been established on the basis of the normal vascular anatomy and of various technical radiological aspects.In some few rare cases,diagnosis of a congenital vascular anomaly can be made accidentally by interventional radiologists,making the procedure of the TIPSS placement extremely difficult or in some cases technically impossible.This report describes a rare vascular malformation characterized by the absence of the right superior vena cava and Persistence of the left superior vena cava in a patient with a diagnosis of advanced liver cirrhosis who needed a TIPSS placement in order to control refractory ascites.

关键词： Left superior vena cava Persistence Liver cirrhosis Refractory ascites Transjugular intrahepatic portosystemic shunt