Mathematical medicine and biology : a journal of the IMA最新文献_第2页

Forecasting the changes between endemic and epidemic phases of a contagious disease, with the example of COVID-19. 以 COVID-19 为例，预测传染病在流行期和流行期之间的变化。

Mathematical medicine and biology : a journal of the IMA Pub Date : 2024-08-20 DOI: 10.1093/imammb/dqae012

Jacques Demongeot, Pierre Magal, Kayode Oshinubi

{"title":"Forecasting the changes between endemic and epidemic phases of a contagious disease, with the example of COVID-19.","authors":"Jacques Demongeot, Pierre Magal, Kayode Oshinubi","doi":"10.1093/imammb/dqae012","DOIUrl":"https://doi.org/10.1093/imammb/dqae012","url":null,"abstract":"Background: Predicting the endemic/epidemic transition during the temporal evolution of a contagious disease.Methods: Indicators for detecting the transition endemic/epidemic, with four scalars to be compared, are calculated from the daily reported news cases: coefficient of variation, skewness, kurtosis, and entropy. The indicators selected are related to the shape of the empirical distribution of the new cases observed over 14 days. This duration has been chosen to smooth out the effect of weekends when fewer new cases are registered. For finding a forecasting variable, we have used the principal component analysis (PCA), whose first principal component (a linear combination of the selected indicators) explains a large part of the observed variance and can then be used as a predictor of the phenomenon studied (here the occurrence of an epidemic wave).Results: A score has been built from the four proposed indicators using the PCA, which allows an acceptable level of forecasting performance by giving a realistic retro-predicted date for the rupture of the stationary endemic model corresponding to the entrance in the epidemic exponential growth phase. This score is applied to the retro-prediction of the limits of the different phases of the COVID-19 outbreak in successive endemic/epidemic transitions for three countries, France, India, and Japan.Conclusion: We provided a new forecasting method for predicting an epidemic wave occurring after an endemic phase for a contagious disease.","PeriodicalId":94130,"journal":{"name":"Mathematical medicine and biology : a journal of the IMA","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142010169","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

Biological invasions and epidemics with nonlocal diffusion along a line. 沿线非局部扩散的生物入侵和流行病。

Mathematical medicine and biology : a journal of the IMA Pub Date : 2024-08-05 DOI: 10.1093/imammb/dqae014

Henri Berestycki, Jean-Michel Roquejoffre, Luca Rossi

{"title":"Biological invasions and epidemics with nonlocal diffusion along a line.","authors":"Henri Berestycki, Jean-Michel Roquejoffre, Luca Rossi","doi":"10.1093/imammb/dqae014","DOIUrl":"https://doi.org/10.1093/imammb/dqae014","url":null,"abstract":"The goal of this work is to understand and quantify how a line with nonlocal diffusion given by an integral enhances a reaction-diffusion process occurring in the surrounding plane. This is part of a long term programme where we aim at modelling, in a mathematically rigorous way, the effect of transportation networks on the speed of biological invasions or propagation of epidemics. We prove the existence of a global propagation speed and characterise in terms of the parameters of the system the situations where such a speed is boosted by the presence of the line. In the course of the study we also uncover unexpected regularity properties of the model. On the quantitative side, the two main parameters are the intensity of the diffusion kernel and the characteristic size of its support. One outcome of this work is that the propagation speed will significantly be enhanced even if only one of the two is large, thus broadening the picture that we have already drawn in our previous works on the subject, with local diffusion modelled by a standard Laplacian. We further investigate the role of the other parameters, enlightening some subtle effects due to the interplay between the diffusion in the half plane and that on the line. Lastly, in the context of propagation of epidemics, we also discuss the model where, instead of a diffusion, displacement on the line comes from a pure transport term.","PeriodicalId":94130,"journal":{"name":"Mathematical medicine and biology : a journal of the IMA","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141891446","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

KPP transition fronts in a one-dimensional two-patch habitat. 一维双斑块生境中的 KPP 过渡前沿。

Mathematical medicine and biology : a journal of the IMA Pub Date : 2024-07-30 DOI: 10.1093/imammb/dqae011

François Hamel, Mingmin Zhangy

引用次数: 0

Mathematical modelling, selection and hierarchical inference to determine the minimal dose in IFNα therapy against myeloproliferative neoplasms. 通过数学建模、选择和层次推理，确定 IFNα 治疗骨髓增殖性肿瘤的最小剂量。

Mathematical medicine and biology : a journal of the IMA Pub Date : 2024-06-15 DOI: 10.1093/imammb/dqae006

Gurvan Hermange, William Vainchenker, Isabelle Plo, Paul-Henry Cournède

引用次数: 0

Phenotype divergence and cooperation in isogenic multicellularity and in cancer. 同源多细胞和癌症中的表型分化与合作

Mathematical medicine and biology : a journal of the IMA Pub Date : 2024-06-15 DOI: 10.1093/imammb/dqae005

Frank Ernesto Alvarez, Jean Clairambault

{"title":"Phenotype divergence and cooperation in isogenic multicellularity and in cancer.","authors":"Frank Ernesto Alvarez, Jean Clairambault","doi":"10.1093/imammb/dqae005","DOIUrl":"10.1093/imammb/dqae005","url":null,"abstract":"We discuss the mathematical modelling of two of the main mechanisms that pushed forward the emergence of multicellularity: phenotype divergence in cell differentiation and between-cell cooperation. In line with the atavistic theory of cancer, this disease being specific of multicellular animals, we set special emphasis on how both mechanisms appear to be reversed, however not totally impaired, rather hijacked, in tumour cell populations. Two settings are considered: the completely innovating, tinkering, situation of the emergence of multicellularity in the evolution of species, which we assume to be constrained by external pressure on the cell populations, and the completely planned-in the body plan-situation of the physiological construction of a developing multicellular animal from the zygote, or of bet hedging in tumours, assumed to be of clonal formation, although the body plan is largely-but not completely-lost in its constituting cells. We show how cancer impacts these two settings and we sketch mathematical models for them. We present here our contribution to the question at stake with a background from biology, from mathematics and from philosophy of science.","PeriodicalId":94130,"journal":{"name":"Mathematical medicine and biology : a journal of the IMA","volume":" ","pages":"135-155"},"PeriodicalIF":0.0,"publicationDate":"2024-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141545723","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 Model of Individual BMI Trajectories. 个人体重指数轨迹模型。

Mathematical medicine and biology : a journal of the IMA Pub Date : 2024-03-15 DOI: 10.1093/imammb/dqad009

Laurens Bogaardt, Anoukh van Giessen, H Susan J Picavet, Hendriek C Boshuizen

引用次数: 0

Asymptotic properties of the Lotka-Volterra competition and mutualism model under stochastic perturbations. 随机扰动下 Lotka-Volterra 竞争与互惠模型的渐近特性

Mathematical medicine and biology : a journal of the IMA Pub Date : 2024-03-15 DOI: 10.1093/imammb/dqae001

Leonid Shaikhet, Andrei Korobeinikov

{"title":"Asymptotic properties of the Lotka-Volterra competition and mutualism model under stochastic perturbations.","authors":"Leonid Shaikhet, Andrei Korobeinikov","doi":"10.1093/imammb/dqae001","DOIUrl":"10.1093/imammb/dqae001","url":null,"abstract":"Stochastically perturbed models, where the white noise type stochastic perturbations are proportional to the current system state, the most realistically describe real-life biosystems. However, such models essentially have no equilibrium states apart from one at the origin. This feature makes analysis of such models extremely difficult. Probably, the best result that can be found for such models is finding of accurate estimations of a region in the model phase space that serves as an attractor for model trajectories. In this paper, we consider a classical stochastically perturbed Lotka-Volterra model of competing or symbiotic populations, where the white noise type perturbations are proportional to the current system state. Using the direct Lyapunov method in a combination with a recently developed technique, we establish global asymptotic properties of this model. In order to do this, we, firstly, construct a Lyapunov function that is applicable to the both competing (and globally stable) and symbiotic deterministic Lotka-Volterra models. Then, applying this Lyapunov function to the stochastically perturbed model, we show that solutions with positive initial conditions converge to a certain compact region in the model phase space and oscillate around this region thereafter. The direct Lyapunov method allows to find estimates for this region. We also show that if the magnitude of the noise exceeds a certain critical level, then some or all species extinct via process of the stochastic stabilization ('stabilization by noise'). The approach applied in this paper allows to obtain necessary conditions for the extinction. Sufficient conditions for the extinction (that for this model occurs via the process that is known as the 'stochastic stabilization', or the 'stabilization by noise') are found applying the Khasminskii-type Lyapunov functions.","PeriodicalId":94130,"journal":{"name":"Mathematical medicine and biology : a journal of the IMA","volume":" ","pages":"19-34"},"PeriodicalIF":0.0,"publicationDate":"2024-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139643727","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

Dosage optimization for reducing tumor burden using a phenotype-structured population model with a drug-resistance continuum. 利用具有耐药性连续体的表型结构群体模型优化剂量，减轻肿瘤负担。

Mathematical medicine and biology : a journal of the IMA Pub Date : 2024-03-15 DOI: 10.1093/imammb/dqae003

Lifeng Han, Osman N Yogurtcu, Marisabel Rodriguez Messan, Wencel Valega-Mackenzie, Ujwani Nukala, Hong Yang

{"title":"Dosage optimization for reducing tumor burden using a phenotype-structured population model with a drug-resistance continuum.","authors":"Lifeng Han, Osman N Yogurtcu, Marisabel Rodriguez Messan, Wencel Valega-Mackenzie, Ujwani Nukala, Hong Yang","doi":"10.1093/imammb/dqae003","DOIUrl":"10.1093/imammb/dqae003","url":null,"abstract":"Drug resistance is a significant obstacle to effective cancer treatment. To gain insights into how drug resistance develops, we adopted a concept called fitness landscape and employed a phenotype-structured population model by fitting to a set of experimental data on a drug used for ovarian cancer, olaparib. Our modeling approach allowed us to understand how a drug affects the fitness landscape and track the evolution of a population of cancer cells structured with a spectrum of drug resistance. We also incorporated pharmacokinetic (PK) modeling to identify the optimal dosages of the drug that could lead to long-term tumor reduction. We derived a formula that indicates that maximizing variation in plasma drug concentration over a dosing interval could be important in reducing drug resistance. Our findings suggest that it may be possible to achieve better treatment outcomes with a drug dose lower than the levels recommended by the drug label. Acknowledging the current limitations of our work, we believe that our approach, which combines modeling of both PK and drug resistance evolution, could contribute to a new direction for better designing drug treatment regimens to improve cancer treatment.","PeriodicalId":94130,"journal":{"name":"Mathematical medicine and biology : a journal of the IMA","volume":" ","pages":"35-52"},"PeriodicalIF":0.0,"publicationDate":"2024-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139975237","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

Impact of climate change on vegetation patterns in Altay Prefecture, China. 气候变化对中国阿勒泰地区植被格局的影响。

Mathematical medicine and biology : a journal of the IMA Pub Date : 2024-03-15 DOI: 10.1093/imammb/dqae002

Li Li, Yi-Zhi Pang, Gui-Quan Sun, Shigui Ruan

{"title":"Impact of climate change on vegetation patterns in Altay Prefecture, China.","authors":"Li Li, Yi-Zhi Pang, Gui-Quan Sun, Shigui Ruan","doi":"10.1093/imammb/dqae002","DOIUrl":"10.1093/imammb/dqae002","url":null,"abstract":"Altay Prefecture, a typical arid region in northwestern China, has experienced the climate transition from warming-drying to warming-wetting since 1980s and has attracted widespread attention. Nonetheless, it is still unclear how climate change has influenced the distribution of vegetation in this region. In this paper, a reaction-diffusion model of the climate-vegetation system is proposed to study the impact of climate change (precipitation, temperature and carbon dioxide concentration) on vegetation patterns in Altay Prefecture. Our results indicate that the tendency of vegetation growth in Altay Prefecture improved gradually from 1985 to 2010. Under the current climate conditions, the increase of precipitation results in the change of vegetation pattern structures, and eventually vegetation coverage tends to be uniform. Moreover, we found that there exists an optimal temperature where the spot vegetation pattern structure remains stable. Furthermore, the increase in carbon dioxide concentration induces vegetation pattern transition. Based on four climate change scenarios of the Coupled Model Intercomparison Project Phase 6 (CMIP6), we used the power law range (PLR) to predict the optimal scenario for the sustainable development of the vegetation ecosystem in Altay Prefecture.","PeriodicalId":94130,"journal":{"name":"Mathematical medicine and biology : a journal of the IMA","volume":" ","pages":"53-80"},"PeriodicalIF":0.0,"publicationDate":"2024-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139992245","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

Effects of vaccination on the two-strain transmission dynamics of COVID-19: Dougherty County, Georgia, USA, as a case study. 疫苗接种对COVID-19两株传播动态的影响:以美国乔治亚州多尔蒂县为例

Mathematical medicine and biology : a journal of the IMA Pub Date : 2023-12-15 DOI: 10.1093/imammb/dqad007

Buddhi Pantha, Jemal Mohammed-Awel, Naveen K Vaidya

{"title":"Effects of vaccination on the two-strain transmission dynamics of COVID-19: Dougherty County, Georgia, USA, as a case study.","authors":"Buddhi Pantha, Jemal Mohammed-Awel, Naveen K Vaidya","doi":"10.1093/imammb/dqad007","DOIUrl":"10.1093/imammb/dqad007","url":null,"abstract":"The emergence of multiple strains of SARS-COV-2 has made it complicated to predict and control the COVID-19 pandemic. Although some vaccines have been effective in reducing the severity of the disease, these vaccines are designed for a specific strain of the virus and are usually less effective for other strains. In addition, the waning of vaccine-induced immunity, reinfection of recovered people, and incomplete vaccination are challenging to the vaccination program. In this study, we developed a detailed model to describe the multi-strain transmission dynamics of COVID-19 under vaccination. We implemented our model to examine the impact of inter-strain transmission competition under vaccination on the critical outbreak indicators: hospitalized cases, undiagnosed cases, basic reproduction numbers, and the overtake-time by a new strain to the existing strain. In particular, our results on the dependence of the overtake-time on vaccination rates, progression-to-infectious rate, and relative transmission rates provide helpful information for managing a pandemic with circulating two strains. Furthermore, our results suggest that a reduction in the relative transmission rates and a decrease in vaccination dropout rates or an increase in vaccination rates help keep the reproduction number of both strains below unity and keep the number of hospitalized cases and undiagnosed cases at their lowest levels. Moreover, our analysis shows that the second and booster-dose vaccinations are useful for further reducing the reproduction number.","PeriodicalId":94130,"journal":{"name":"Mathematical medicine and biology : a journal of the IMA","volume":" ","pages":"308-326"},"PeriodicalIF":0.0,"publicationDate":"2023-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"107593169","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