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Expansion of tandem repeats and oligomer clustering in coding and noncoding DNA sequences
Buldyrev, Sergey V.; Dokholyan, Nikolay V.; Havlin, Shlomo - In: Physica A: Statistical Mechanics and its Applications 273 (1999) 1, pp. 19-32
We review recent studies of distribution of dimeric tandem repeats and short oligomer clustering in DNA sequences. We find that distribution of dimeric tandem repeats in coding DNA is exponential, while in noncoding DNA it often has long power-law tails. We explain this phenomenon using mutation...
Persistent link: https://www.econbiz.de/10010664800
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The starry sky model of the percolation phase transition II. The conductivity backbone created by the Hall coefficient
Skal, Asya S. - In: Physica A: Statistical Mechanics and its Applications 234 (1996) 1, pp. 12-22
A ‘special nodes and blobs’ model of percolation phase transition, obtained from the distribution function of a kinetic coefficient, such as conductivity and the Hall and Seebeck coefficients, is introduced.
Persistent link: https://www.econbiz.de/10010587328
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A percolation study of electrical properties of reservoir rocks
Wang, Ke-Wen; Sun, Jian-Meng; Guan, Ji-Teng; Zhu, Da-Wei - In: Physica A: Statistical Mechanics and its Applications 380 (2007) C, pp. 19-26
This paper focuses on theory studies of rock electrical properties using percolation theory. The results show that classical site and bond percolation models can well describe the characteristics of the pore connectivity and the effects on the electrical resistivity. Because of the...
Persistent link: https://www.econbiz.de/10010588861
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Effective scalar properties of the critical region in functionally graded materials
Van Siclen, C.D - In: Physica A: Statistical Mechanics and its Applications 322 (2003) C, pp. 5-12
The critical region in a compositionally graded material occurs where the dominant phase ceases to percolate, and so is poorly treated by effective medium theories. To address this problem, equations for the size and effective scalar properties of that region are obtained from percolation theory.
Persistent link: https://www.econbiz.de/10010589938
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The starry sky model of the percolation phase transition I. The ‘special’ nodes
Skal, Asya S. - In: Physica A: Statistical Mechanics and its Applications 234 (1996) 1, pp. 1-11
The real physical phenomena of ‘special’ nodes in a percolation phase transition, obtained from the distribution functions of the Joule heat and the Hall and Seebeck coefficients are considered. The ‘special’ nodes N (p) (the ‘active’ nodes for the Hall and Seebeck coefficients and...
Persistent link: https://www.econbiz.de/10010874051
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Percolation theory and fragmentation measures in social networks
Chen, Yiping; Paul, Gerald; Cohen, Reuven; Havlin, Shlomo; … - In: Physica A: Statistical Mechanics and its Applications 378 (2007) 1, pp. 11-19
We study the statistical properties of a recently proposed social networks measure of fragmentation F after removal of a fraction q of nodes or links from the network. The measure F is defined as the ratio of the number of pairs of nodes that are not connected in the fragmented network to the...
Persistent link: https://www.econbiz.de/10011058475
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A two-dimensional model of pair aggregation
Gómez, J.B.; Pacheco, A.F. - In: Physica A: Statistical Mechanics and its Applications 243 (1997) 3, pp. 217-228
We modify the usual percolation theory (PT) by subtituting single particles which occupy sites on a two-dimensional square lattice, by pairs of particles linked by strings whose maximum length is a multiple of the basic lattice spacing. The crossing of random length strings of the pairs leads to...
Persistent link: https://www.econbiz.de/10011058601
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Percolation effects in mixed β/β″-alumina crystals
Maass, P; Meyer, M; Bunde, A - In: Physica A: Statistical Mechanics and its Applications 266 (1999) 1, pp. 197-202
Mixed β/β″-alumina crystals are two-dimensional ion conductors, whose conductivities vary dramatically upon mixing of two types of mobile ions. We summarize a theoretical model, which can explain these conductivity variations quantitatively. According to the model, percolation effects are...
Persistent link: https://www.econbiz.de/10011060318
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Tracer dispersion in double porosity porous media with nonlinear adsorption
Drazer, G.; Chertcoff, R.; Bruno, L.; Rosen, M. - In: Physica A: Statistical Mechanics and its Applications 257 (1998) 1, pp. 371-375
Tracer dispersion measurements in double porosity porous media with a nonlinear adsorption isotherm are reported … medium. This tagging technique allows us to work in a linear adsorption regime where classical dispersion results are used …. The basic dispersion mechanisms are related to physicochemical and geometrical properties of the porous medium. We …
Persistent link: https://www.econbiz.de/10010599570
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Maximization of statistical heterogeneity: From Shannon’s entropy to Gini’s index
Eliazar, Iddo; Sokolov, Igor M. - In: Physica A: Statistical Mechanics and its Applications 389 (2010) 16, pp. 3023-3038
–in the four following scenarios: (i) Shannon entropy maximization subject to a given dispersion level; (ii) Gini index … maximization subject to a given dispersion level; (iii) Shannon entropy maximization subject to a given Gini index; (iv) Gini index …
Persistent link: https://www.econbiz.de/10011063693