Related Experiment Video
Updated: Jan 27, 2026

06:44
Age-dependent Dynamics of Locomotion in Caenorhabditis elegans: A Lyapunov Exponent Analysis
Published on: September 23, 2025
547
Dynamical analysis of an age-structured multi-group SIVS epidemic model
Junyuan Yang1, Rui Xu, Xiaofeng Luo
1Complex Systems Research Center, Shanxi University, Taiyuan, Shanxi 030006, P.R. China.
Mathematical Biosciences and Engineering : MBE
|March 14, 2019
Summary
This study introduces a multi-group SIVS model accounting for host heterogeneity. Disease dynamics are determined by the basic reproduction number, offering insights into transmission routes.
Area of Science:
- Epidemiology
- Mathematical Biology
- Disease Modeling
Background:
- Host heterogeneities like space, gender, and age significantly influence disease mechanisms and transmission.
- Understanding these factors is crucial for developing effective disease control strategies.
Purpose of the Study:
- To propose a multi-group Susceptible-Infected-Vaccinated-Susceptible (SIVS) epidemic model incorporating inter-group, intra-group, and age structures.
- To analyze the threshold dynamics of the proposed model.
Main Methods:
- Utilized renewal equations to derive the basic reproduction number as the spectral radius of the next-generation operator.
- Applied integral semigroup theory and Lyapunov methods to analyze the system's stability.
- Established the existence and uniqueness of the endemic equilibrium under specific parameter assumptions.
Main Results:
- The basic reproduction number was successfully obtained for the multi-group SIVS model.
- The existence and uniqueness of the endemic equilibrium were proven.
- Demonstrated that the system's threshold dynamics are entirely governed by the basic reproduction number.
Conclusions:
- Host heterogeneities are fundamental to understanding disease transmission.
- The developed multi-group SIVS model provides a robust framework for analyzing epidemic dynamics.
- The basic reproduction number serves as a critical threshold parameter for disease persistence.
Related Concept Videos
Aging
667
Aging is a complex biological phenomenon influenced by various processes that affect cellular and systemic functions. Several prominent theories attempt to explain its mechanisms, highlighting cellular limitations, oxidative damage, and hormonal changes as central factors in aging.
Cellular Clock Theory
The cellular clock theory posits that the human lifespan is closely tied to the finite capacity of cells to divide, a phenomenon governed by telomeres, which are protective caps at the ends of...
Cellular Clock Theory
The cellular clock theory posits that the human lifespan is closely tied to the finite capacity of cells to divide, a phenomenon governed by telomeres, which are protective caps at the ends of...
667
Structure of Benzene: Kekulé Model
11.8K
In 1865, August Kekule suggested the structure of benzene according to the structural theory of organic chemistry based on the three assertions—formula of benzene is C6H6, all the hydrogens of benzene are equivalent, and each carbon must have four bonds due to its tetravalency.
He proposed that benzene has a cyclic structure of six carbon atoms attached to one hydrogen atom each, with three alternating pi bonds.
He proposed that benzene has a cyclic structure of six carbon atoms attached to one hydrogen atom each, with three alternating pi bonds.
11.8K
The Effect of Aging on Tissues
3.5K
Several body functions deteriorate with age. The external signs of aging are easily identifiable. For example, the skin becomes dry, less elastic, and thins out, forming wrinkles. The skin of the face begins to appear looser due to a decrease in the levels of elastic and collagen fibers in the connective tissue. Additionally, melanin production in the hair follicle decreases with age, resulting in gray hair. Moreover, the senses of sight and hearing decline, so glasses and hearing aids may...
3.5K
Structure of Benzene: Molecular Orbital Model
12.3K
According to the molecular orbital (MO) model, benzene has a planar structure with a regular hexagon of six sp2 hybridized carbons. As shown in Figure 1, each carbon is bonded to three other atoms with C–C–C and H–C–C bond angles of 120°. The C–H bond length is 109 pm, and the C–C bond length is 139 pm which is midway between the single bond length of sp3 hybridized carbons (154 pm) and sp2 hybridized carbons (133 pm).
12.3K
Additional Subnuclear Structures
5.4K
The eukaryotic nucleus is a double membrane-bound organelle that contains nearly all of the cell’s genetic material in the form of chromosomes. It is rightly called the “brain” of the cell as it shoulders the responsibility of responding to various physiological processes, stress, altered metabolic conditions, and other cellular signals.
The nucleus contains many membrane-less subnuclear organelles or nuclear bodies, such as nucleoli, Cajal bodies, speckles,...
The nucleus contains many membrane-less subnuclear organelles or nuclear bodies, such as nucleoli, Cajal bodies, speckles,...
5.4K
Dynamic Equilibrium
62.4K
A reversible chemical reaction represents a chemical process that proceeds in both forward (left to right) and reverse (right to left) directions. When the rates of the forward and reverse reactions are equal, the concentrations of the reactant and product species remain constant over time and the system is at equilibrium. A special double arrow is used to emphasize the reversible nature of the reaction. The relative concentrations of reactants and products in equilibrium systems vary greatly;...
62.4K

