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Fractional-Order Model for Multi-Drug Antimicrobial Resistance

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Computer Modeling in Engineering & Sciences 2020年第8期124卷 665-682页

作者： M.F.Elettreby Ali S.Alqahtani E.Ahmed Mathematics Department Faculty of ScienceKing Khalid UniversityAbha9004Saudi Arabia Mathematics Department Faculty of ScienceMansoura UniversityMansoura35516Egypt

Drug resistance is one of the most serious phenomena in financial,economic and medical terms.The present paper proposes and investigates a simple mathematical fractional-order model for the phenomenon of multi-drug antimicrobial resistance.The model describes the dynamics of the susceptible and three kinds of infected populations.The first class of the infected society responds to the first antimicrobial drug but resists to the second one.The second infected individuals react to the second antimicrobial drug but resist to the first one.The third class shows resistance to both of the two drugs.We formulate the model and associate it with some of its properties.The stability conditions of the multi-drug antimicrobial resistance equilibrium states are derived.We illustrate the analytical results by some numerical simulations.

关键词： susceptible infectious drug resistance stability predictor-corrector method

Evaluation of Chinese rice varieties resistant to the root-knot nematode Meloidogyne graminicola

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Journal of Integrative Agriculture 2018年第3期17卷 621-630页

作者： ZHAN Li-ping DING Zhong PENG De-liang PENG Huan KONG Ling-an LIU Shi-ming LIU Ying LI Zhong-cai HUANG Wen-kun State Key Laboratory for Biology of Plant Diseases and Insect Pests/Institute of Plant Protection Chinese Academy of Agricultural Sciences Beijing 100193 P.R.China College of Plant Protection Hunan Agricultural University Changsha 410128 P.R.China Agriculture Bureau of Hanshou County Hunan Province Changde 415900 P.R.China

The root-knot nematode Meloidogyne graminicola, which is distributed worldwide, is considered a major constraint on rice production in Asia. The present study used the root gall index and number of nematodes inside the roots to evaluate resistance/susceptibility to M. graminicola in different subpopulations of Oryza sativa （aus, hybrid aus, indica, hybrid indica, temperate japonica, tropical japonica）. Nematode development in highly resistant varieties was also evaluated. Analyses of randomly selected 35 varieties showed the number of M. graminicola nematodes inside the roots correlated very strongly （r=0.87, P≤0.05） with the nematode gall index, and the results from pot and field experiments revealed similar rankings of the varieties for resistance/susceptibility. Among the 136 tested varieties, temperate japonica displayed the highest gall index, followed by tropical japonica, indica, hybrid indica, aus, and hybrid aus. Zhonghua 11 （aus）, Shenliangyou 1 （hybrid aus） and Cliangyou 4418 （hybrid indica） were highly resistant to M. graminicola under both pot and field conditions. Further examination of nematode development suggested that compared to susceptible rice, M. graminicola penetrated less often into highly resistant varieties and more frequently failed to develop into females. The promising varieties found in the present research might be useful for the breeding of hybrid rice in China and for the further development of practical nematode management measures.

关键词： Meloidogyne graminicola rice varieties resistant susceptible resistance evaluation

Qualitative analysis of a stochastic SEITR epidemic model with multiple stages of infection and treatment

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Infectious Disease Modelling 2020年第1期5卷 61-90页

作者： Olusegun Michael Otunuga Mobolaji O.Ogunsolu Department of Mathematics Marshall UniversityOne John Marshall DriveHuntingtonWVUSA Department of Mathematics and Statistics University of South Florida4202E Fowler AveTampaFlUSA

We present a mathematical analysis of the transmission of certain diseases using a stochastic susceptible-exposed-infectious-treated-recovered(SEITR)model with multiple stages of infection and treatment and explore the effects of treatments and external fluctuations in the transmission,treatment and recovery rates.We assume external fluctuations are caused by variability in the number of contacts between infected and susceptible individuals.It is shown that the expected number of secondary infections produced(in the absence of noise)reduces as treatment is introduced into the population.By defining RT,n and R T,n as the basic deterministic and stochastic reproduction numbers,respectively,in stage n of infection and treatment,we show mathematically that as the intensity of the noise in the transmission,treatment and recovery rates increases,the number of secondary cases of infection increases.The global stability of the disease-free and endemic equilibrium for the deterministic and stochastic SEITR models is also presented.The work presented is demonstrated using parameter values relevant to the transmission dynamics of Influenza in the United States from October 1,2018 through May 4,2019 influenza seasons.

关键词： susceptible Infection Treatment Recovery Stochastic epidemic model Stability Reproduction number

Pulse Vaccination Strategy in an Epidemic Model with Two susceptible Subclasses and Time Delay

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Applied Mathematics 2011年第1期2卷 57-63页

作者： Youquan Luo Shujing Gao Shuixian Yan 不详

In this paper, an impulsive epidemic model with time delay is proposed, which susceptible population is divided into two groups: high risk susceptibles and non-high risk susceptibles. We introduce two thresholds R1, R2 and demonstrate that the disease will be extinct if R11 . Our results show that larger pulse vaccination rates or a shorter the period of pulsing will lead to the eradication of the disease. The conclusions are confirmed by numerical simulations.

关键词： High Risk susceptible Non-High Risk susceptible Pulse Vaccination Extinction

A STUDY ON THE PHYSICAL MECHANISM OF RESISTANCE OF MAIN POPLAR STRAINS AGAINST CRYPTORRHYNCHUS LAPATHIL.IN NORTH CHINA

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Journal of Northeast Forestry University 1993年第1期4卷 91-106页

作者： Liu Jingquan Hou Aiju Ding Fujun Northeast Forestry University Northeast Forestry University China

The physical mechanism of resistance of poplar against Cryptorrhynchus lapathiL.is directly correlated with the morphological structure of bark,concerning the following 5aspects:1.It is correlated with whether surface bark of larva transvered tunnel crack or not,ear-ly or late.Those that do not crack or crack late are susceptible strains while those that crack ear-ly are resistant strains.2.It is correlated with thickness of cork layer.Thick cork layer can in-crease resistance against pest while thin one is more susceptible to pest attack.3.It is related withage of tree.Trees at the age of 1-2 possess immunity to the pest,at 3-4 are relatively resistant,at5-8 are susceptible and over 9 are more resistant.4.It is also correlated with the rate of trees‘healing round the holes of larva tunnels.Those healing faster are resistant while those healingslower arc susceptible.5.It is related with the number of various scars on bark surface.

关键词： poplar susceptible tunnels crease faster concerning morphological cracking larvae immunity

Ciprofloxacin non-susceptible Streptococcus pyogenes due to mutations in parC gene and its homology analysis

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China Medical Abstracts(Internal Medicine) 2013年第3期30卷 144-145页

作者：张晓飞 Pharma Coll Zhejiang Technol Univ

Objective To investigate the resistant mechanism of Streptococcus pyogenes to ciprofloxacin and its homology.Methods Forty-eight isolates of Streptococcus pyogenes were collected from patients diagnosed with scarflet

关键词： Streptococcus homology susceptible isolates penicillin contained clone antibiotics gyrA mutation

Characteristics and Risk factors of Psychosomatic Symptoms Related to Female Tubal Sterilization in Rural Area in Hunan Province, China: A Prospective Study

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Journal of Reproduction and Contraception 2002年第1期13卷 37-52页

作者：刘破资岳伟华郝伟杨德森凌天牖张友明彭光辉武昆刘红华苏中华王厚亮谢永标 Department of Mental Health the Second Xiangya Hospital Central South UniversityChangsha 410011 China Department of Family Planning of Hunan Province Changsha 410011 China

Objectives To study characteristics of psychosomatic symptoms related to sterilization, to find out risk factors and their roles ascribed to psychosomatic symptoms, and to establish a mathematic model for screening out susceptible women. Methods: This study enrolled 776 women in rural area at three counties of Linxiang, Qiyang, Changsha of Hunan province in China between February 1990 and April 1992. Brief Neurosis Screening Scale (BNSS), Symptom Checklist 90 (SCL-90), sensitivity to pain, suggestibility were used to indicate subjects' psychological status. Logistic regression model and retrograde discriminant analysis were applied to develop a mathematical model. Results: Prevalence of psychosomatic reactions or symptoms was 54.8% before sterilization, 26.6% at three months and 16.4% at one year after operation respectively. Psychosomatic symptoms were verified to be the result of joint effects of multiple risk factors. The following risk factors were associated with postoperative symptoms: anger-hostility (RR=33.71), high suggestibility (RR=4.53), high neuroticism (RR=3.44), sensitivity to pain (RR=2.14) and operative sites (RR=2.05). A mathematical model to estimate the probability of developing psychosomatic symptoms in sterilization was established.Conclusions: More than half of women suffered from psychosomatic reactions before operation, and some of them did not recover after operation. The postoperative psychosomatic symptoms are the joint effect of multiple risk factors.

关键词： female tubal sterilization psychosomatic symptom susceptible prospective study

A Modified Epidemic Chain Binomial Model (MECBM) and Its 2,3-Introductory Probabilities

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Open Journal of Statistics 2017年第2期7卷 225-239页

作者： Dilip C. Nath Kishore K. Das Tandrima Chakraborty Administration Assam University Silchar India Department of Statistics Gauhati University Guwahati India

Through the ages, human life and happiness are affected much by wide spread diseases, an unpredictable phenomenon. And infectious disease spread is one of the most unsolvable problems. How infection evolves, how it spreads from person to person and mainly which pattern it follows are some questions which are always unanswerable. Out of many techniques, discrete epidemic models like the chain binomial model are ones which are applied to describe the physical phenomena of spreading infectious diseases in a household. In this paper, an attempt has been made to develop a modified epidemic chain model by assuming a beta distribution of third kind for the probability of being infected by contact with a given infection from the same household with closed population. This paper emphasized mainly on developing the probabilities of all possible epidemic chains with two introductory cases for three-, four- and five-member household and three introductory cases for four- and five-member household. The key phenomenon towards developing this paper was to provide an extension of the modified chain binomial model and its possible probabilities.

关键词： Beta Distribution Infection susceptible

A Modified Epidemic Chain Binomial Model

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Open Journal of Statistics 2016年第1期6卷 1-6页

作者： Dilip C. Nath Kishore K. Das Tandrima Chakraborty Department of Statistics Gauhati University Guwahati India

Discrete epidemic models are applied to describe the physical phenomena of spreading infectious diseases in a household. In this paper, an attempt has been made to develop a modified epidemic chain model by assuming a beta distribution of third kind for the probability of being infected by contact with a given infective from the same household with closed population. This paper emphasizes mainly on developing the probabilities of all possible epidemic chains with one introductory case for three, four and five member household. The key phenomenon towards developing this paper is to provide an alternative model of chain binomial model.

关键词： Beta Distribution Infection susceptible