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

The emergence of order in natural systems is a constant source of inspiration for both physical and biological sciences. While the spatial order characterizing for example the crystals has been the basis of many advances in contemporary physics, most complex systems in nature do not offer such high degree of order. Many of these systems form complex networks whose nodes are the elements of the system and edges represent the interactions between them. 
Traditionally complex networks have been described by the random graph theory founded in 1959 by Paul Erdohs and Alfred Renyi. One of the defining features of random graphs is that they are statistically homogeneous, and their degree distribution (characterizing the spread in the number of edges starting from a node) is a Poisson distribution. In contrast, recent empirical studies, including the work of our group, indicate that the topology of real networks is much richer than that of random graphs. In particular, the degree distribution of real networks is a power-law, indicating a heterogeneous topology in which the majority of the nodes have a small degree, but there is a significant fraction of highly connected nodes that play an important role in the connectivity of the network. 
The scale-free topology of real networks has very important consequences on their functioning. For example, we have discovered that scale-free networks are extremely resilient to the random disruption of their nodes. On the other hand, the selective removal of the nodes with highest degree induces a rapid breakdown of the network to isolated subparts that cannot communicate with each other. 
The non-trivial scaling of the degree distribution of real networks is also an indication of their assembly and evolution. Indeed, our modeling studies have shown us that there are general principles governing the evolution of networks. Most networks start from a small seed and grow by the addition of new nodes which attach to the nodes already in the system. This process obeys preferential attachment: the new nodes are more likely to connect to nodes with already high degree. We have proposed a simple model based on these two principles wich was able to reproduce the power-law degree distribution of real networks. Perhaps even more importantly, this model paved the way to a new paradigm of network modeling, trying to capture the evolution of networks, not just their static topology.

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Statistical mechanics of complex networks

Preface to the Princeton Landmarks in Biology Edition vii Preface xi Symbols Used xiii 1. The Importance of Islands 3 2. Area and Number of Speicies 8 3. Further Explanations of the Area-Diversity Pattern 19 4. The Strategy of Colonization 68 5. Invasibility and the Variable Niche 94 6. Stepping Stones and Biotic Exchange 123 7. Evolutionary Changes Following Colonization 145 8. Prospect 181 Glossary 185 References 193 Index 201

The Theory of Island Biogeography

http://www.maths.qmul.ac.uk/%7Elatora/report_06.pdf

Complex networks: Structure and dynamics

https://www.tau.ac.il/%7Eklafter1/258.pdf

The random walk's guide to anomalous diffusion: a fractional dynamics approach

Dispersion relations of the intercalate modes in graphite intercalation compounds

The distribution of points corresponding to the angular projection of a fractal is shown to become homogeneous for relatively large angels. In addition the corresponding correlation function w(θ) depends strongly on the angular half-width of the considered sample. These results show that, contrary to the usual interpretation, the observed angular correlations of galaxies can actually be compatible with a fractal structure in space.

The angular projection of fractals and its relevance for the galaxy distributions

The basic hypothesis of a post-Copernican Cosmological theory is that {\em all the points} of the Universe have to be essentially equivalent: this hypothesis is required in order to avoid any privileged {\em observer}. This assumption has been implemented by Einstein in the so-called Cosmological Principles (CP): {\em all the positions} in the Universe have to be essentially equivalent, so that the Universe is homogeneous. This situation implies also the condition of spherical symmetry about every point, so that the Universe in also Isotropic. There is a hidden assumption in the formulation of the CP in regard to the hypothesis that all the points are equivalent In fact, the condition that all the occupied points are statistically equivalent with respect to their environment correspond to the property of of Local Isotropy. It is generally believed that the Universe cannot be isotropic about every point without being also homogeneous [1]. Actually Local Isotropy does not necessarily implies homogeneity; in fact a topology theorem states that homogeneity is implied by the condition of local isotropy together with {\em the assumption of the analyticity or regularity} for the distribution of matter. Up to the seventies analyticity was an obvious implicit assumption in any physical problem. Recently however we have learned about intrinsically irregular structures for which analyticity should be considered as a property to be tested with appropriate analysis of experiment.

Cosmological principle and the debate about large scale structures distribution

We study the equilibrium properties of a generalized lattice gas as applied to the cooperative phenomena of superionic conductors. For a model describing interacting Frenkel defects with various degeneracies we discuss the competing effects of degeneracy and interaction. The phase diagram is computed within mean field theory and the possibility of first order, second order and continuous transitions is shown. For a one dimensional model with two sites and different degeneracies we derive explicit exact results for the site occupancies as functions of temperature. Finally we consider the effect of long range (coulomb) interactions for the site occupancy correlation in a partly filled ionic channel. This effect is shown to be relevant and not reproducible by effective short range interactions.

Cooperative phenomena in superionic conductors within generalized lattice gas models

Recently reported data on the resistivity and its temperature dependence of ${\mathrm{C}}_{8}$As${\mathrm{F}}_{5}$ are interpreted in terms of a microscopic theory of the electron-phonon scattering. The theory includes the scattering by the graphite phonons within a tight-binding framework and that by the modes of the charged intercalate for which the anisotropic screening is explicitly considered.

Luciano Pietronero

Papers

Dispersion relations of the intercalate modes in graphite intercalation compounds

The angular projection of fractals and its relevance for the galaxy distributions

Cosmological principle and the debate about large scale structures distribution

Cooperative phenomena in superionic conductors within generalized lattice gas models

Mechanisms of electron-phonon scattering and resistivity in graphite intercalation compounds