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

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

入侵病原体与宿主之间呈动态平衡，以维持病原体成功地寄生在宿主体内而不致宿主死亡，这是许多寄生虫感染的一个重要特征。包括曼氏血吸虫在内的许多蠕虫感染中，持续的炎症反应比病原体本身对宿主的危害更大，降低宿主的免疫反应具有重要意义。曼氏血吸虫感染后，宿主活化CD4^＋Th2细胞，分泌IL-4、IL-5和IL-13。最近研究表明IL-13是肝组织纤维化的重要调节因子。

IL-13受体α2降低血吸虫病肉芽肿的炎症反应并延长宿主存活时间[英]/Mentink-Kane MM,Cheever AW，Thompson RW，et al//Proc Natl Acad Sci U S A

Near equilibrium, small current fluctuations are described by a Gaussian distribution with a linear-response variance regulated by the dissipation. Here, we demonstrate that dissipation still plays a dominant role in structuring large fluctuations arbitrarily far from equilibrium. In particular, we prove a linear-response-like bound on the large deviation function for currents in Markov jump processes. We find that nonequilibrium current fluctuations are always more likely than what is expected from a linear-response analysis. As a small-fluctuations corollary, we derive a recently conjectured uncertainty bound on the variance of current fluctuations.

/pdf/dissipation-bounds-all-steady-state-current-fluctuations-43bcevvwoi.pdf

Dissipation Bounds All Steady-State Current Fluctuations.

介绍Plos Computational Biology主编Philip E．Bourne关于论文发表的10务简单法则，包括：读很多论文，客观看待自身工作，选择好的编辑，提高英语水平，忍受退稿，提高论文质量等。以期对医学生和研究人员发表文章提供有益帮助。

Plos Computational Biology主编关于论文获得发表的10条简单法则的评析

Heat engines should ideally have large power output, operate close to Carnot efficiency and show constancy, ie, exhibit only small fluctuations in this output For steady-state heat engines, driven by a constant temperature difference between the two heat baths, we prove that out of these three requirements only two are compatible Constancy enters quantitatively the conventional trade-off between power and efficiency Thus, we rationalize and unify recent suggestions for overcoming this simple trade-off Our universal bound is illustrated for a paradigmatic model of a quantum dot solar cell and for a Brownian gyrator delivering mechanical work against an external force

Universal Trade-Off between Power, Efficiency, and Constancy in Steady-State Heat Engines.

For current fluctuations in nonequilibrium steady states of Markovian processes, we derive four different universal bounds valid beyond the Gaussian regime. Different variants of these bounds apply to either the entropy change or any individual current, e.g., the rate of substrate consumption in a chemical reaction or the electron current in an electronic device. The bounds vary with respect to their degree of universality and tightness. A universal parabolic bound on the generating function of an arbitrary current depends solely on the average entropy production. A second, stronger bound requires knowledge both of the thermodynamic forces that drive the system and of the topology of the network of states. These two bounds are conjectures based on extensive numerics. An exponential bound that depends only on the average entropy production and the average number of transitions per time is rigorously proved. This bound has no obvious relation to the parabolic bound but it is typically tighter further away from equilibrium. An asymptotic bound that depends on the specific transition rates and becomes tight for large fluctuations is also derived. This bound allows for the prediction of the asymptotic growth of the generating function. Even though our results are restricted to networks with a finite number of states, we show that the parabolic bound is also valid for three paradigmatic examples of driven diffusive systems for which the generating function can be calculated using the additivity principle. Our bounds provide a general class of constraints for nonequilibrium systems.

/pdf/universal-bounds-on-current-fluctuations-4ve2pl0i1l.pdf

Universal bounds on current fluctuations.

For fluctuating currents in nonequilibrium steady states, the recently discovered thermodynamic uncertainty relation expresses a fundamental relation between their variance and the overall entropic cost associated with the driving. We show that this relation holds not only for the long-time limit of fluctuations, as described by large deviation theory, but also for fluctuations on arbitrary finite time scales. This generalization facilitates applying the thermodynamic uncertainty relation to single molecule experiments, for which infinite time scales are not accessible. Importantly, often this finite-time variant of the relation allows inferring a bound on the entropy production that is even stronger than the one obtained from the long-time limit. We illustrate the relation for the fluctuating work that is performed by a stochastically switching laser tweezer on a trapped colloidal particle.

Finite-time generalization of the thermodynamic uncertainty relation.

The thermodynamic uncertainty relation provides an inequality relating any mean current, the associated dispersion and the entropy production rate for arbitrary non-equilibrium steady states. Applying it here to a general model of a molecular motor running against an external force or torque, we show that the thermodynamic efficiency of such motors is universally bounded by an expression involving only experimentally accessible quantities. For motors pulling cargo through a viscous fluid, a universal bound for the corresponding Stokes efficiency follows as a variant. A similar result holds if mechanical force is used to synthesize molecules of high chemical potential. Crucially, no knowledge of the detailed underlying mechano-chemical mechanism is required for applying these bounds.

https://iopscience.iop.org/article/10.1088/1742-5468/2016/12/124004/pdf

Patrick Pietzonka

Papers

Universal Trade-Off between Power, Efficiency, and Constancy in Steady-State Heat Engines.

Universal bounds on current fluctuations.

Finite-time generalization of the thermodynamic uncertainty relation.

Universal bound on the efficiency of molecular motors

Universal bound on the efficiency of molecular motors