抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Fractional Differential Equations

N G van Kampen 1981 Amsterdam: North-Holland xiv + 419 pp price Dfl 180 This is a book which, at a lower price, could be expected to become an essential part of the library of every physical scientist concerned with problems involving fluctuations and stochastic processes, as well as those who just enjoy a beautifully written book. It provides an extensive graduate-level introduction which is clear, cautious, interesting and readable.

https://iopscience.iop.org/article/10.1088/0031-9112/34/4/040/pdf

Stochastic Processes in Physics and Chemistry

Fractional dynamics has experienced a firm upswing during the past few years, having been forged into a mature framework in the theory of stochastic processes. A large number of research papers developing fractional dynamics further, or applying it to various systems have appeared since our first review article on the fractional Fokker–Planck equation (Metzler R and Klafter J 2000a, Phys. Rep. 339 1–77). It therefore appears timely to put these new works in a cohesive perspective. In this review we cover both the theoretical modelling of sub- and superdiffusive processes, placing emphasis on superdiffusion, and the discussion of applications such as the correct formulation of boundary value problems to obtain the first passage time density function. We also discuss extensively the occurrence of anomalous dynamics in various fields ranging from nanoscale over biological to geophysical and environmental systems.

/pdf/the-restaurant-at-the-end-of-the-random-walk-recent-1w7yr3snyb.pdf

The restaurant at the end of the random walk: recent developments in the description of anomalous transport by fractional dynamics

We consider $f(R,T)$ modified theories of gravity, where the gravitational Lagrangian is given by an arbitrary function of the Ricci scalar $R$ and of the trace of the stress-energy tensor $T$. We obtain the gravitational field equations in the metric formalism, as well as the equations of motion for test particles, which follow from the covariant divergence of the stress-energy tensor. Generally, the gravitational field equations depend on the nature of the matter source. The field equations of several particular models, corresponding to some explicit forms of the function $f(R,T)$, are also presented. An important case, which is analyzed in detail, is represented by scalar field models. We write down the action and briefly consider the cosmological implications of the $f(R,{T}^{\ensuremath{\phi}})$ models, where ${T}^{\ensuremath{\phi}}$ is the trace of the stress-energy tensor of a self-interacting scalar field. The equations of motion of the test particles are also obtained from a variational principle. The motion of massive test particles is nongeodesic, and takes place in the presence of an extra-force orthogonal to the four velocity. The Newtonian limit of the equation of motion is further analyzed. Finally, we provide a constraint on the magnitude of the extra acceleration by analyzing the perihelion precession of the planet Mercury in the framework of the present model.

$f(R,T)$ gravity

/pdf/reaction-transport-systems-4yeja04uat.pdf

Reaction-Transport Systems

The classical wave-of-advance model of the neolithic transition (i.e., the shift from hunter-gatherer toagricultural economies) is based on Fisher’s reaction-diffusion equation. Here we present an extensionof Einstein’s approach to Fickian diffusion, incorporating reaction terms. On this basis we show thatsecond-order terms in the reaction-diffusion equation, which have been neglected up to now, are notin fact negligible but can lead to important corrections. The resulting time-delayed model agrees quitewell with observations. [S0031-9007(98)08286-6]

/pdf/time-delayed-theory-of-the-neolithic-transition-in-europe-2nl8ypgxez.pdf

Time-Delayed Theory of the Neolithic Transition in Europe

General Concepts- Reaction Kinetics- Reactions and Transport: Diffusion, Inertia, and Subdiffusion- Random Walks and Mesoscopic Reaction-Transport Equations- Front Propagation- Reaction-Diffusion Fronts- Reaction-Transport Fronts Propagating into Unstable States- Reaction-Diffusion Fronts in Complex Structures- Ecological Applications- Biomedical Applications- Spatial Instabilities and Patterns- Persistence and Extinction of Populations in Finite Domains- Turing Instabilities in Homogeneous Systems- Turing Instabilities in Reaction-Diffusion Systems with Temporally or Spatially Varying Parameters- Chemical and Biological Applications of Turing Systems- Pattern Formation in Spatially Discrete Systems

Reaction-Transport Systems: Mesoscopic Foundations, Fronts, and Spatial Instabilities

We review the recent theoretical progress in the formulation and solution of the front speed problem for time-delayed reaction-diffusion systems. Most of the review is focused on hyperbolic equations. They have been widely used in recent years, because they allow for analytical solutions and yield a realistic description of some relevant phenomena. The theoretical methods are applied to a range of applications, including population dynamics, forest fire models, bistable systems and combustion wavefronts. We also present a detailed account of successful predictions of the models, as assessed by comparison to experimental data for some biophysical systems, without making use of any free parameters. Areas where the work reviewed may contribute to future progress are discussed.

/pdf/wavefronts-in-time-delayed-reaction-diffusion-systems-theory-3rqbigtamr.pdf

Vicenç Méndez

Papers

Reaction-Transport Systems

Time-Delayed Theory of the Neolithic Transition in Europe

Reaction-Transport Systems: Mesoscopic Foundations, Fronts, and Spatial Instabilities

Wavefronts in time-delayed reaction-diffusion systems. Theory and comparison to experiment

Stochastic Foundations in Movement Ecology