IMA journal of mathematics applied in medicine and biology最新文献_第10页

Toxicity in a water column following the stratification of a cyanobacterial population development in a calm lake. 在平静的湖泊中，蓝藻种群发展分层后水柱中的毒性。

IMA journal of mathematics applied in medicine and biology Pub Date : 1999-03-01 DOI: 10.1093/IMAMMB/16.1.93

A. P. Belov, J. Giles, R. Wiltshire

{"title":"Toxicity in a water column following the stratification of a cyanobacterial population development in a calm lake.","authors":"A. P. Belov, J. Giles, R. Wiltshire","doi":"10.1093/IMAMMB/16.1.93","DOIUrl":"https://doi.org/10.1093/IMAMMB/16.1.93","url":null,"abstract":"Cyanobacteria, including the genera Anabaena, Aphanizomenon, Microcystis, and Oscillatoria, are known to release or have the potential to release phycotoxins into the water. Indeed, there are documented cases of both animal and human intoxication. Data obtained from field observations and laboratory experiments demonstrate a correlation between the development of the cyanobacterial population and the level of phycotoxin present in the water, though it should be noted that not all cyanobacterial blooms are toxic. The development of cyanobacterial populations is described by a dynamical model which accounts for factors that include algal growth, degradation, and light-driven buoyancy under the assumption of an isothermal, calm, and nutrient-abundant lake. A semiempirical mathematical model for water-column toxicity is developed and is used in conjunction with an improved result for the density of the cyanobacteria population obtained from the dynamical model. Light transfer through the water column, light absorption, the implication of the differentiated attenuation of light by the water, and its diurnal effect on the cyanobacteria population is considered. The result of which is a plausible description of the seasonal development of cyanobacteria populations and of the toxicity within the water body.","PeriodicalId":77168,"journal":{"name":"IMA journal of mathematics applied in medicine and biology","volume":"16 1 1","pages":"93-110"},"PeriodicalIF":0.0,"publicationDate":"1999-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1093/IMAMMB/16.1.93","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"61178592","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Toxicity in a water column following the stratification of a cyanobacterial population development in a calm lake. 在平静的湖泊中，蓝藻种群发展分层后水柱中的毒性。

IMA journal of mathematics applied in medicine and biology Pub Date : 1999-03-01

A P Belov, J D Giles, R J Wiltshire

{"title":"Toxicity in a water column following the stratification of a cyanobacterial population development in a calm lake.","authors":"A P Belov, J D Giles, R J Wiltshire","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Cyanobacteria, including the genera Anabaena, Aphanizomenon, Microcystis, and Oscillatoria, are known to release or have the potential to release phycotoxins into the water. Indeed, there are documented cases of both animal and human intoxication. Data obtained from field observations and laboratory experiments demonstrate a correlation between the development of the cyanobacterial population and the level of phycotoxin present in the water, though it should be noted that not all cyanobacterial blooms are toxic. The development of cyanobacterial populations is described by a dynamical model which accounts for factors that include algal growth, degradation, and light-driven buoyancy under the assumption of an isothermal, calm, and nutrient-abundant lake. A semiempirical mathematical model for water-column toxicity is developed and is used in conjunction with an improved result for the density of the cyanobacteria population obtained from the dynamical model. Light transfer through the water column, light absorption, the implication of the differentiated attenuation of light by the water, and its diurnal effect on the cyanobacteria population is considered. The result of which is a plausible description of the seasonal development of cyanobacteria populations and of the toxicity within the water body.</p>","PeriodicalId":77168,"journal":{"name":"IMA journal of mathematics applied in medicine and biology","volume":"16 1","pages":"93-110"},"PeriodicalIF":0.0,"publicationDate":"1999-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21204780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A mathematical analysis of the spread of HIV/AIDS in Japan. 艾滋病在日本传播的数学分析。

IMA journal of mathematics applied in medicine and biology Pub Date : 1999-03-01 DOI: 10.1093/IMAMMB16.1.111

M. Kakehashi

{"title":"A mathematical analysis of the spread of HIV/AIDS in Japan.","authors":"M. Kakehashi","doi":"10.1093/IMAMMB16.1.111","DOIUrl":"https://doi.org/10.1093/IMAMMB16.1.111","url":null,"abstract":"The spread of HIV/AIDS in Japan was analysed using a mathematical model incorporating pair formations between adults and sexual contacts with commercial sex workers. The parameters involved in the model were carefully specified as realistically as possible to the actual situation in Japan. Plausible ranges were assigned to those parameters for which values are not known precisely. The model was used to simulate the effect of HIV infected commercial sex workers introduced into a population without HIV. It was shown that the model could generate different scenarios, an explosive infection or a temporal spread, according to different settings of the parameters. Then the condition for occasional introduction of HIV infected commercial sex workers to be able to cause an explosive spread of HIV infection was analysed. This condition was summarized in terms of the critical transmission probability so that we could easily evaluate the degree of the risk. For some unclear parameters, sensitivity to the critical transmission probability was calculated. We also calculated a plausible range of the critical transmission probability using the Latin hypercube sampling method where the parameters were distributed on the plausible ranges. According to the analyses of the model it is concluded that the actual situation of HIV spread in Japan should lie very near the critical point that determines whether the explosive HIV spread actually takes place. This also suggests that effective action taken immediately could be useful to prevent explosive HIV infection in Japan.","PeriodicalId":77168,"journal":{"name":"IMA journal of mathematics applied in medicine and biology","volume":"15 4 1","pages":"299-311"},"PeriodicalIF":0.0,"publicationDate":"1999-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"61183345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 15

Delay effect in a model for virus replication. 病毒复制模型中的延迟效应。

IMA journal of mathematics applied in medicine and biology Pub Date : 1999-03-01 DOI: 10.1093/IMAMMB/16.1.29

Judy Tam

引用次数: 68

Modelling and simulation of chemotherapy of haematological and gynaecological cancers. 血液学和妇科癌症化疗的建模和模拟。

IMA journal of mathematics applied in medicine and biology Pub Date : 1999-03-01

F K Nani, M N Oğuztöreli

引用次数: 0

Dynamics of Japanese encephalitis--a study in mathematical epidemiology. 日本脑炎的动态——数学流行病学研究。

IMA journal of mathematics applied in medicine and biology Pub Date : 1999-03-01 DOI: 10.1093/IMAMMB/16.1.1

A. Ghosh, P. Tapaswi

{"title":"Dynamics of Japanese encephalitis--a study in mathematical epidemiology.","authors":"A. Ghosh, P. Tapaswi","doi":"10.1093/IMAMMB/16.1.1","DOIUrl":"https://doi.org/10.1093/IMAMMB/16.1.1","url":null,"abstract":"An S-->I-->R-->S (susceptible-infective-recovered-susceptible) epidemiological model coupling the dynamics of the spread of Japanese encephalitis (JE) in two populations, human and reservoir animals (pigs, cattle, equines, birds, etc.) through a vector population (a particular species of mosquitos, Culex vishnui, Culex tritaeniorhynchus, etc.) is discussed. We assume that there is a constant recruitment rate of the susceptibles into both the populations, whereas the death rates are proportional to the population sizes, which are hence variables. We also assume that the human population is regulated by the disease. Conditions for the existence of a unique endemic equilibrium were found, and the endemicity of the disease is discussed. The threshold values determine whether the disease dies out or approaches an endemic equilibrium. The persistence of disease and disease-related death can lead to a new equilibrium population size. The criteria for eradication of the disease have been worked out. The analytical results corresponding to the solutions of our system are verified by numerical analysis and computer simulation. The dynamics of disease transmission of JE during 1948-1956 in Japan were also investigated with the help of available data.","PeriodicalId":77168,"journal":{"name":"IMA journal of mathematics applied in medicine and biology","volume":"16 1 1","pages":"1-27"},"PeriodicalIF":0.0,"publicationDate":"1999-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1093/IMAMMB/16.1.1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"61178332","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 11

Estimating vaccine coverage by using computer algebra. 利用计算机代数估计疫苗覆盖率。

IMA journal of mathematics applied in medicine and biology Pub Date : 1998-12-28 DOI: 10.1093/IMAMMB/17.2.137

Doris Altmann, K. Altmann

引用次数: 5

Stability analysis of the FitzHugh-Nagumo differential equations driven by impulses: applied to the electrical firing of magnocellular neurons. 脉冲驱动的FitzHugh-Nagumo微分方程的稳定性分析:应用于大细胞神经元的放电。

IMA journal of mathematics applied in medicine and biology Pub Date : 1998-12-01 DOI: 10.1093/imammb/15.4.367

A. Milne, Z. Chalabi

引用次数: 1

Patient-ventilator interaction: a general model for nonpassive mechanical ventilation. 患者-呼吸机相互作用:非被动机械通气的一般模型。

IMA journal of mathematics applied in medicine and biology Pub Date : 1998-12-01 DOI: 10.1093/IMAMMB/15.4.321

P. Crooke, J. D. Head, John J. Marini, J. Hotchkiss

引用次数: 14

Stability analysis of the FitzHugh-Nagumo differential equations driven by impulses: applied to the electrical firing of magnocellular neurons. 脉冲驱动的FitzHugh-Nagumo微分方程的稳定性分析:应用于大细胞神经元的放电。

IMA journal of mathematics applied in medicine and biology Pub Date : 1998-12-01

A E Milne, Z S Chalabi

引用次数: 0