arXiv subjects

Zhen-Hui He

Publications and source records attributed to Zhen-Hui He.

8 recordsLinked to original sources

arXiv2008

Spatiotemporal Noise Triggering Infiltrative Tumor Growth under Immune Surveillance

A spatiotemporal noise is assumed to reflect the environmental fluctuation in a spatially extended tumor system. We introduce firstly the structure factor to reveal the invasive tumor growth quantitatively. The homogenous environment can lead to an expansive growth of the tumor cells, while the inhomogenous environment underlies an infiltrative growth. The different responses of above two cases are separated by a characteristic critical intensity of the spatiotemporal noise. Theoretical and numerical results present a close annotation to the clinical images.

q-bio.OT↗

arXiv2007

Noise Correlation Induced Synchronization in a Mutualism Ecosystem

Understanding the cause of the synchronization of population evolution is an important issue for ecological improvement. Here we present a Lotka-Volterra-type model driven by two correlated environmental noises and show, via theoretical analysis and direct simulation, that noise correlation can induce a synchronization of the mutualists. The time series of mutual species exhibit a chaotic-like fluctuation, which is independent to the noise correlation, however, the chaotic fluctuation of mutual species ratio decreases with the noise correlation. A quantitative parameter defined for characterizing chaotic fluctuation provides a good approach to measure when the complete synchronization happens.

q-bio.OT↗

arXiv2006

Spatiotemporal Fluctuation Induced Transition in a Tumor Model with Immune Surveillance

We report on a simple model of spatial extend anti-tumor system with a fluctuation in growth rate, which can undergo a nonequilibrium phase transition. Three states as excited, sub-excited and non-excited states of a tumor are defined to describe its growth. The multiplicative noise is found to be double-face: The positive effect on a non-excited tumor and the negative effect on an excited tumor.

physics.bio-ph↗

arXiv2006

Pure multiplicative stochastic resonance of anti-tumor model with seasonal modulability

The effects of pure multiplicative noise on stochastic resonance in an anti-tumor system modulated by a seasonal external field are investigated by using theoretical analyses of the generalized potential and numerical simulations. For optimally selected values of the multiplicative noise intensity quasi-symmetry of two potential minima and stochastic resonance are observed. Theoretical results and numerical simulations are in good quantitative agreement.

q-bio.OT↗

arXiv2005

Sensitive predators and endurant preys in an ecosystem driven by correlated noises

We investigate the Volterra ecosystem driven by correlated noises. The competition of the predators induces an increasing in population density of the predators. The competition of the preys, however, leads the predators to decay. The predators may have better stability under strong correlated noises. The predators undergo a sensitivity to a random environment, whereas the preys exhibit a surprising endurance to this stochasticity.

q-bio.PE↗

arXiv2005

Noise-induced first-order transition in anti-tumor immunotherapy

We studied the single-variable dynamics model of the tumor growth. A first-order phase transition induced by an additive noise is shown to reproduce the main features of tumor growth under immune surveillance. The critical average cells population has a power-law function relationship with the immune coefficient.

physics.med-ph↗

arXiv2005

Stochastic resonance in the growth of a tumor induced by correlated noises

Multiplicative noise is found to divide the growth law of tumors into two parts in a logistic model, which is driven by additive and multiplicative noises simultaneously. The Fokker-Planck equation was also derived to explain the fact that the influence of the intensity of multiplicative noise on the growth of tumor cells has a stochastic resonance-like characteristic. An appropriate intensity of multiplicative noise is benefit to the growth of the tumor cells. The correlation between two sorts of noises weakens the stochastic resonance-like characteristic. Homologous noises promote the growth of the tumor cells.

physics.bio-ph↗

arXiv2005

Influence of Correlated Noises on Growth of a Tumor

We studied the effect of additive and multiplicative noises on the growth of a tumor based on a logistic growth model. The steady-state probability distribution and the average population of the tumor cells were given to explain the important roles of correlated noises in the tumor growth. We found that multiplicative noise induces a phase transition of the tumor growth from an uni-stable state to a bi-stable state; the relationship between the intensity of multiplicative noise and the population of the tumor cells showed a stochastic resonance-like characteristic. It was also confirmed that additive noise weakened rather than extinguish the tumor growth. Homologous noises, however, promote the growth of a tumor. We also discussed about the relationship between the tumor treatment and the model.

physics.bio-ph↗