Abstract：
:We discuss an N-dimensional model for diffusion of age dependent populations. Let rho(x, t, a) be the population density at time t, age a and spatial position x, and let u(x, t) = [formula: see text] rho(x, t, a) da be the total population at t and x. The directed dispersal model to be discussed, with diffusion depending on the gradient of the total population, is [formula see text] With some assumptions on the form of the death and birth modulus, this system is reduced to a mixed parabolic-hyperbolic system containing the Porous Medium equation in RN. We discuss the existence, regularity and localization of the solution of this reduced system.
journal_name
Math Bioscijournal_title
Mathematical biosciencesauthors
Hernández GEdoi
10.1016/s0025-5564(97)10014-1subject
Has Abstractpub_date
1998-04-01 00:00:00pages
37-56issue
1eissn
0025-5564issn
1879-3134pii
S0025-5564(97)10014-1journal_volume
149pub_type
杂志文章abstract：:Stability of the 'guardian of the genome' tumor suppressor protein p53 is regulated predominantly through its ubiquitination. The ubiquitin-specific protease HAUSP plays an important role in this process. Recent experiments showed that p53 demonstrates a differential response to changes in HAUSP which nature and signi...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2007.05.005
更新日期：2007-11-01 00:00:00
abstract：:The aim of this paper is to apply machine learning as a method to refine a manually constructed CPN for the assessment of the severity of the systemic inflammatory response syndrome (SIRS).The goal of tuning the CPN is to create a scoring system that uses only objective data, compares favourably with other severity-sc...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2016.11.004
更新日期：2017-02-01 00:00:00
abstract：:The statistical characterization of the spatial structure of large animal groups has been very limited so far, mainly due to a lack of empirical data, especially in three dimensions (3D). Here we focus on the case of large flocks of starlings (Sturnus vulgaris) in the field. We reconstruct the 3D positions of individu...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2008.05.006
更新日期：2008-07-01 00:00:00
abstract：:According to metapopulation theory, the capacity of a habitat patch network to support the persistence of a species is measured by the metapopulation capacity of the patch network. Mathematically, metapopulation capacity is given by the leading eigenvalue lambda(M) of an appropriately constructed non-negative n x n ma...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/s0025-5564(02)00150-5
更新日期：2003-02-01 00:00:00
abstract：:Mathematical models of biological systems often have components that vary on different timescales. This multi-timescale character can lead to problems when doing computer simulations, which can require a great deal of computer time so that the components that change on the fastest time scale can be resolved. Mathemati...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2016.07.003
更新日期：2017-05-01 00:00:00
abstract：:We consider estimates of certain time-domain parameters of a bivariate stationary-point process based on modified periodogram statistics. These estimates are shown to be asymptotically normal under regularity conditions. In the computations of the estimates, the advantage of using the FFT algorithm is demonstrated. Th...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/0025-5564(91)90061-m
更新日期：1991-05-01 00:00:00
abstract：:The only animal of which the complete neural circuitry is known at the submicroscopical level is the nematode Caenorhabditis elegans. This anatomical knowledge is complemented by functional insight from electrophysiological experiments in the related nematode Ascaris lumbricoides, which show that Ascaris motor neurons...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/0025-5564(93)90033-7
更新日期：1993-11-01 00:00:00
abstract：:We study the invasion of a top predator into a food chain in a chemostat. For each trophic level, a bioenergetic model is used in which maintenance and energy reserves are taken into account. Bifurcation analysis is performed on the set of nonlinear ordinary differential equations which describe the dynamic behaviour ...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/s0025-5564(98)10083-4
更新日期：1999-03-15 00:00:00
abstract：:Classification of microarray data has always been a challenging task because of the enormous number of genes. In this study, a clustering method by integrating plant stress response gene expression data with biological knowledge is presented. Clustering is one of the promising tools for attribute reduction, but gene c...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2015.06.005
更新日期：2015-08-01 00:00:00
abstract：:Most models of the spread of HIV/AIDS assume that the probability of transmission from an infected individual to a susceptible partner has some constant value per sexual act, compounding independently randomly (so that ten acts with one person chosen from a particular group has, on average, the same risk as one act wi...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/0025-5564(92)90006-i
更新日期：1992-02-01 00:00:00
abstract：:The two methods available for analyzing the global structural identifiability of the parameters of a nonlinear system with a specified input function, the Taylor series approach and the similarity transformation approach, are compared and contrasted through application to three examples. It is shown that, as for linea...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/0025-5564(90)90055-4
更新日期：1990-11-01 00:00:00
abstract：:Therapeutic enhancement of humoral immune response to microbial attack is addressed as the stochastic optimal control of a dynamic system. Without therapy, the modeled immune response depends upon the initial concentration of pathogens in a simulated attack. Immune response can be augmented by agents that kill the pat...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2004.06.004
更新日期：2004-10-01 00:00:00
abstract：:The effects of pulsatile GnRH stimulation on anterior pituitary cells are studied using perifusion cell cultures, where constantly moving culture medium over the immobilized cells allows intermittent GnRH delivery. The LH content of the outgoing medium serves as a readout of the GnRH signaling pathway activation in th...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2016.03.016
更新日期：2016-06-01 00:00:00
abstract：:Mutual interference and prey refuge are important drivers of predator-prey dynamics. The "exponent" or degree of mutual interference has been under much debate in theoretical ecology. In the present work, we investigate the interplay of the mutual interference exponent, and prey refuge, on the behavior of a predator-p...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2020.108407
更新日期：2020-08-01 00:00:00
abstract：:Habitat heterogeneity can have profound effects on the spreading dynamics of invasive species. Using integro-difference equations, we investigate the spreading dynamics in a one-dimensional heterogeneous landscape comprising alternating favourable and unfavourable habitat patches or randomly generated habitat patches ...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2016.02.013
更新日期：2016-05-01 00:00:00
abstract：:A class of models is considered in which the number of unknown parameters exceeds the number of independent equations that are derived from the input/observation configuration. It is shown that, under certain circumstances, if the number of unknown parameters is sufficiently decreased by setting some of the exit param...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/0025-5564(95)00049-6
更新日期：1996-03-01 00:00:00
abstract：:An inherent problem in studying the behavior of a metabolic pathway is the impossibility of developing a complete, detailed model that includes all the cellular processes that have an impact on the set of fluxes in such a pathway. Lacking this, one requires some means of modeling the interactions between a metabolic p...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/0025-5564(90)90049-5
更新日期：1990-06-01 00:00:00
abstract：:The existence of cooperation in this world is a mysterious phenomenon. One of the mechanisms that explain the evolution of cooperation is repeated interaction. If interactions between the same individuals repeat and individuals cooperate conditionally, cooperation can evolve. A previous study pointed out that if indiv...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2017.04.002
更新日期：2017-07-01 00:00:00
abstract：:A mathematical analysis of the stability in human respiration, based on the tau-decomposition method, is conducted on a simple, but realistic CO2 model of the respiratory system. This model incorporates a two-compartment representation (lungs and tissues) for the plant and a very general class of controller. By derivi...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/s0025-5564(98)10028-7
更新日期：1998-09-01 00:00:00
abstract：:A multicompartmental model is proposed to deal with the spread of the HIV epidemic. Stratification with respect to high- and low-risk groups is taken into account, introducing a "fuzzy" decomposition of the compartment of susceptibles. The infectivity period is staged using different levels of CD4 cell counts. Asympto...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/0025-5564(91)90021-a
更新日期：1991-12-01 00:00:00
abstract：:Two optimization problems are considered: Harvesting from a structured population with maximal gain subject to the condition of non-extinction, and vaccinating a population with prescribed reduction of the reproduction number of the disease at minimal costs. It is shown that these problems have a similar structure and...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2005.09.001
更新日期：2007-04-01 00:00:00
abstract：:Frailty models are becoming increasingly popular in multivariate survival analysis. Shared frailty models in particular are often used despite their limitations. To overcome their disadvantages numerous correlated frailty models were established during the last decade. In the present study, we examine bivariate correl...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2004.11.010
更新日期：2005-11-01 00:00:00
abstract：:A pandemic of a novel Coronavirus emerged in December of 2019 (COVID-19), causing devastating public health impact across the world. In the absence of a safe and effective vaccine or antivirals, strategies for controlling and mitigating the burden of the pandemic are focused on non-pharmaceutical interventions, such a...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2020.108364
更新日期：2020-07-01 00:00:00
abstract：:In linear, stochastic dynamics it is shown that the quasideterministic population size is equivalent to the mean population size. The quasideterministic dynamics are defined by the conditional infinitesimal mean of the process. The stochastic component of the dynamics includes both Gaussian and Poisson white noise, wi...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/0025-5564(89)90010-2
更新日期：1989-03-01 00:00:00
abstract：:In many cicadas, a phenomenon is observed in which the peak of emergence of males precedes that of females (protandry). Generally, it is known that the ecology of emergence of insects is closely related to mating, and protandry is said to be the strategy of males to eclose early and to attempt mating with virgin femal...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2018.08.006
更新日期：2018-11-01 00:00:00
abstract：:To understand how a gene regulatory network functioning as an oscillator is built, a genetic regulatory network with two transcriptional delays is investigated. We show by mathematical analysis and simulation that autorepression of mRNA and protein can provide a mechanism for the intracellular oscillator. Based on the...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2008.05.004
更新日期：2008-09-01 00:00:00
abstract：:In this paper, we consider a deterministic malaria transmission model with standard incidence rate and treatment. Human population is divided into susceptible, infectious and recovered subclasses, and mosquito population is split into susceptible and infectious classes. It is assumed that, among individuals with malar...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2015.05.005
更新日期：2015-08-01 00:00:00
abstract：:Two-component systems (TCSs) are widely employed by bacteria to sense specific external signals and conduct an appropriate response via a phosphorylation cascade within the cell. The TCS of the agr operon in the bacterium Staphylococcus aureus forms part of a regulatory process termed quorum sensing, a cell-to-cell co...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2010.03.001
更新日期：2010-06-01 00:00:00
abstract：:Colorado River is a unique ecosystem and provides important ecological services such as habitat for fish species as well as water power energy supplies. River management for this ecosystem requires assessment and decision support tools for fish which involves protecting, restoring as well as forecasting of future cond...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2018.02.006
更新日期：2018-04-01 00:00:00
abstract：:Cancer virotherapy represents a dynamical system that requires mathematical modeling for complete understanding of the outcomes. The combination of virotherapy with radiation (radiovirotherapy) has been recently shown to successfully eliminate tumors when virotherapy alone failed. However, it introduces a new level of...
journal_title：Mathematical biosciences
pub_type： 杂志文章
doi：10.1016/j.mbs.2005.11.001
更新日期：2006-01-01 00:00:00
