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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Yelmanova V. A., Khrustalev B. P., Balaev A. D.
Заглавие : Transition from low-spin to high-spin states in clusters of polymerized acetylacetonate of Fe-3+
Место публикации : Solid State Commun.: PERGAMON-ELSEVIER SCIENCE LTD, 1982. - Vol. 43, Is. 3. - P175-177. - ISSN 0038-1098, DOI 10.1016/0038-1098(82)90105-3
Примечания : Cited References: 3
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Rautian S. G., Safonov V. P., Chubakov P. A., Shalaev V.M., Shtokman M. I.
Заглавие : Surface-enhanced parametric scattering of light by silver clusters
Место публикации : JETP Letters. - 1988. - Vol. 47, Is. 4. - P.243-246. - ISSN 0021-3640
Примечания : Cited References: 6
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Butenko A. V., Shalayev V. M., Stockman M. I.
Заглавие : Giant impurity nonlinearities in optics of fractal clusters
Место публикации : Zhurnal |Eksperim. Teor. Fiz.: MEZHDUNARODNAYA KNIGA, 1988. - Vol. 94, Is. 1. - P107-124. - ISSN 0044-4510
Примечания : Cited References: 12
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Butenko A. V., Danilova Y. E., Ishikaev S. M., Karpov S. V., Popov A. K., Rautian S. G., Safonov V. P., Slabko V. V., Crubakov P. A., Shalaev V. M., Shtokman M. I.
Заглавие : Nonlinear optics of metallic fractal clusters
Место публикации : Izvestiya Akademii Nauk SSSR Seriya Fizicheskaya. - 1989. - Vol. 53, Is. 6. - P.1195-1201. - ISSN 0367-6765
Примечания : Cited References: 13
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Sshalaev V. M., Botet R., Jullien R.
Заглавие : Resonant light-scattering by fractal clusters
Место публикации : Phys. Rev. B. - 1991. - Vol. 44, Is. 22. - P.12216-12225. - ISSN 0163-1829, DOI 10.1103/PhysRevB.44.12216
Примечания : Cited References: 19
Предметные рубрики: AEROGELS
OPTICS
Аннотация: A scale-invariant theory of resonant Rayleigh scattering by fractal clusters is developed. Our main result is that the scattering cross section is greatly enhanced, because of the presence of very high local fields, which are correlated and strongly fluctuating. Simulations dealing with two examples of fractal structures, namely, random walk and cluster-cluster aggregates, are presented. The numerical results confirm the theoretical predictions of the scaling behavior for both absorption and scattering, and allow us to obtain the corresponding exponents. In addition to the results for scattering, the large scale of the simulations of the present work provides a comprehensive confirmation and a substantial extension of a recent study by Markel, Muratov, Stockman, and George [Phys. Rev. B 43, 8183 (1991)].
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Stockman M. I., Shalaev V. M., Moskovits M., Botet R., George T. F.
Заглавие : Enhanced raman-scattering by fractal clusters - scale-invariant theory
Место публикации : Phys. Rev. B. - 1992. - Vol. 46, Is. 5. - P.2821-2830. - ISSN 0163-1829, DOI 10.1103/PhysRevB.46.2821
Примечания : Cited References: 22
Предметные рубрики: AGGREGATION
LIGHT
Аннотация: A scale-invariant theory of Raman scattering of light by fractal clusters is developed. The enhancement factor G(RS) of Raman scattering is shown to scale in terms of a properly chosen spectral variable X. The critical indices of the enhancement factor are found to be determined by the optical spectral dimension of the fractal. Numerical modeling is carried out and shown to support the analytical results obtained. The theory, which does not contain any adjustable parameters, agrees well with experimental data on surface-enhanced Raman scattering over a wide spectral range.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Alekseyev K. N., Berman G. P., Tsifrinovich V. I., Frishman A. M.
Заглавие : Dynamic chaos in magnetic systems
Место публикации : Uspekhi Fiz. Nauk. - 1992. - Vol. 162, Is. 7. - P.81-118. - ISSN 0042-1294
Примечания : Cited References: 99
Предметные рубрики: CLASSICAL SPIN CLUSTERS
YTTRIUM-IRON-GARNET
PARALLEL-PUMPED MAGNONS
NON-LINEAR SYSTEMS
QUANTUM CHAOS
FAT FRACTALS
FERROMAGNETIC (CH3NH3)2CUCL4
NONLINEAR DYNAMICS
LEVEL REPULSION
KICKED TOP
Аннотация: A review of the theoretical and experimental investigations of chaos in magnetic systems is represented. Both dissipative and Hamiltonian systems are considered. Basic scenarios of transitions to chaos in such systems are overlooked. Models and characteristics of chaotic oscillations in a parametric excitation of spin waves. NMR-masers, dynamics of spin chains, motion of spin in an external oscillating magnetic field and nonlinear NMR with a dynamic frequency shift are discussed. A problem of the quantum chaos in spin systems is analysed.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Shalaev V. M., Botet R., Butenko A. V.
Заглавие : Localization of collective dipole excitations on fractals
Место публикации : Phys. Rev. B. - 1993. - Vol. 48, Is. 9. - P.6662-6664. - ISSN 1098-0121, DOI 10.1103/PhysRevB.48.6662
Примечания : Cited References: 11
Предметные рубрики: CLUSTERS
Аннотация: Dipole optical excitations on fractals are numerically simulated. It is shown that dipole eigen-modes of fractals are localized. The corresponding localization length dependence on the generalized frequency parameter (dispersion law) has been calculated. The value of optical spectral dimension found from the dispersion relations is in agreement with the result obtained earlier from calculations of the density of eigenstates.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Shalaev V. M., Poliakov E. Y., Markel V. A.
Заглавие : Small-particle composites .2. Nonlinear optical properties
Место публикации : Phys. Rev. B: AMERICAN PHYSICAL SOC, 1996. - Vol. 53, Is. 5. - P2437-2449. - ISSN 0163-1829, DOI 10.1103/PhysRevB.53.2437
Примечания : Cited References: 45
Предметные рубрики: FRACTAL CLUSTERS
RAMAN-SCATTERING
SUSCEPTIBILITY
CONDUCTIVITY
EXCITATIONS
COLLOIDS
LIGHT
Аннотация: Strong fluctuations of local fields may result in very large optical nonlinearities in small-particle composites. Enhancement associated with particle clustering is found for a number of optical processes, including four-wave mixing (FWM), third-harmonic generation (THG), Raman scattering, and nonlinear refraction and absorption in Kerr media. Field fluctuations and optical nonlinear susceptibilities are especially large in fractal clusters. The enhancement of optical processes is expressed in terms of the resonant linear absorption by collective dipolar eigenmodes in a cluster, and quality factors, q, of the modes (q much greater than 1). It is shown that the susceptibility of a composite material consisting of random small-particle clusters is proportional to q(3) for Raman scattering and the Kerr optical nonlinearity, and to q(4) and q(6) for THG and FWM, respectively. For all of these processes, a spectral dependence of the effective susceptibility is found. Broad-scale numerical simulations of the optical response in small-particle composites are performed to complement the theory. The simulations are in reasonable agreement with available experimental data.
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10.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Markel V. A., Shalaev V. M., Poliakov E. Y., George T. F.
Заглавие : Numerical studies of second- and fourth-order correlation functions in cluster-cluster aggregates in application to optical scattering
Место публикации : Phys. Rev. E: AMERICAN PHYSICAL SOC, 1997. - Vol. 55, Is. 6. - P7313-7333. - ISSN 1063-651X, DOI 10.1103/PhysRevE.55.7313
Примечания : Cited References: 21
Предметные рубрики: DIFFUSION-LIMITED AGGREGATION
COLLOIDAL AGGREGATION
FRACTAL CLUSTERS
ANTICORRELATION
SIMULATIONS
Аннотация: Two- and four-point density correlation functions p(2)(r) and p(4)(r) are studied numerically and theoretically in computer-generated three-dimensional lattice cluster-cluster aggregates (CCA) with the number of particles N up to 20 000 in application to the light scattering problem. The ''pure'' aggregation algorithm is used, where subclusters of all possible sizes are allowed to collide. We find that large CCA clusters demonstrate pronounced multiscaling. In particular, the fractal dimension determined from the slope of p(2)(r) at small distances differs from that found from the dependence of the radius of gyration on the number of monomers (according to our data, 1.80 and 1.94, respectively). We also consider different functional forms for p(2) and their general properties and applicability. We find that the best fit to the numerical data is provided by the generalized exponential cutoff function with coefficients depending on N. The latter dependence is a manifestation of multiscaling. We propose some theoretical approaches for calculating p(4)(r), assuming p(2)(r) is known. In particular, we find the small-r asymptote for the p(4)(r) and verify it numerically. In addition, we find that p(4)(r) cannot be represented by a scaling dependence with a cutoff function, like p(2)(r) Instead, p(4)(r) is given by an expansion in terms of integer powers of r(2D-3), where D is the fractal dimension (approximate to 1.8 for CCA clusters).
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11.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Myagkov V. G., Bykova L. E.
Заглавие : Fractal clusters and self-propagating high-temperature synthesis in thin Al/Ge films
Место публикации : JETP Letters. - 1998. - Vol. 67, Is. 5. - P.334-338. - ISSN 0021-3640, DOI 10.1134/1.567669
Примечания : Cited References: 14
Предметные рубрики: DENSE BRANCHING MORPHOLOGY
SINGLE-CRYSTAL GROWTH
AL-GE
PHASE-SEPARATION
Аннотация: Fractal clusters in amorphous thin films are examples of growth models. The main models are the Witten-Sander model and its modifications. It is believed that fractal patterns are formed in the course of the crystallization of an amorphous phase. It is shown that self-propagating high-temperature synthesis can be initiated in an Al/Ge film system and fractal patterns are formed in the reaction products. It is conjectured that the transition of an amorphous phase to a crystalline phase does not play a substantial role in the appearance of such patterns, while the formation of fractal clusters is determined by self-propagating high-temperature synthesis. (C) 1998 American Institute of Physics. [S0021-3640(98)00605-7].
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12.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Antonova A.B., Johansson A.A., Deykhina N.A., Pogrebnyakov D.A., Pavlenko N.I., Rubaylo A.I., Dolgushin F.M., Petrovskii P.V., Ginzburg A.G.
Заглавие : Chemistry of vinylidene complexes. XIII. The reaction between Cp(CO)2MnPt(?-C=CHPh)(?2-dppm) and Fe2(CO)9: Simultaneous formation of the ?3-vinylidene MnFePt and ?4-vinylidene PtFe3 clusters. Crystal structure of (?5-C5H5)MnFePt(? 3-C=CHPh)(CO)6.
Место публикации : Journal of Organometallic Chemistry. - 1999. - Т. 577, № 2. - P.238-242. - ISSN 0022-328X
ГРНТИ : 31.17
РИНЦ
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13.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Churilov G. N., Fedorov A. S., Novikov P. V.
Заглавие : Fullerene C-60 formation in partially ionized carbon vapor
Разночтения заглавия :авие SCOPUS: Fullerene C60 formation in partially ionized carbon vapor
Место публикации : JETP Letters. - 2002. - Vol. 76, Is. 8. - P.522-526. - ISSN 0021-3640, DOI 10.1134/1.1533779
Примечания : Cited References: 15
Предметные рубрики: TOTAL-ENERGY CALCULATIONS
WAVE BASIS-SET
CLUSTERS
GROWTH
Аннотация: The assembling rate of a fullerene C-60 molecule has been theoretically studied as a function of electron concentration and temperature in partially ionized carbon vapor. For C-60 formation via one or two intermediate stages of cluster collisions, it has been shown that there is a region of plasma parameters (the temperature and electron concentration) in which fullerene C-60 is formed more efficiently. The C-60 formation rate versus temperature and electron concentration relationships have been found to correlate with the trends in the collision cross-section of carbon clusters as functions of these parameters. (C) 2002 MAIK "Nauka/Interperiodica".
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14.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Zobov V. E., Popov M. A.
Заглавие : The coordinate of the singular point of generating functions of clusters in the high-temperature dynamics of spin lattice systems with axially symmetric interaction
Место публикации : Theor. Math. Phys.: MAIK NAUKA/INTERPERIODICA/SPRINGER, 2003. - Vol. 136, Is. 3. - P1297-1311. - ISSN 0040-5779, DOI 10.1023/A:1025603416535
Примечания : Cited References: 25
Предметные рубрики: CONSISTENT FLUCTUATING FIELD
NUCLEAR-DOUBLE-RESONANCE
HEISENBERG PARAMAGNET
LINE SHAPE
RELAXATION
SPECTRUM
APPROXIMATION
CRYSTALS
MOMENT
CAF2
Ключевые слова (''Своб.индексиров.''): spin dynamics--singular points--expansion over the reciprocal space dimension--expansion over the reciprocal space dimension--singular points--spin dynamics
Аннотация: We investigate generating functions for equipped trees composed of double bonds of two sorts on a hypercubic lattice of dimension d with built-in fragments. Rules for constructing these clusters are chosen to ensure the estimate for coefficients of power series in time for the longitudinal and transverse autocorrelation functions of the spin system with axially symmetric interaction. We derive a system of two equations for the tree-generating functions and an equation for the generating functions of chains leading from the root to a fragment in a tree using the Bethe approximation and under the condition that mainly bonds of one sort are taken into account. For the face-centered hypercubic lattice, we find the First terms of the 1/d expansion for the coordinate of the singular point of the generating function in both the anisotropic and the isotropic cases taking fragments in the forms of a triangle from four bonds and a four-fold bound pair into account. The obtained result is written in terms of ratios of lattice sums and is generalized to nuclear spin systems with dipole-dipole interaction. The theoretical value of the singular-point coordinate agrees well with the experimental value calculated from the tail of the absorption spectrum of the nuclear magnetic resonance in a barium fluoride monocrystal.
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15.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Karpov S. V., Popov A. K., Slabko V. V.
Заглавие : Photochromic reactions in silver nanocomposites with a fractal structure and their comparative characteristics
Место публикации : Tech. Phys.: MAIK NAUKA/INTERPERIODICA/SPRINGER, 2003. - Vol. 48, Is. 6. - P749-756. - ISSN 1063-7842, DOI 10.1134/1.1583830
Примечания : Cited References: 24
Предметные рубрики: SMALL-PARTICLE COMPOSITES
OPTICAL-PROPERTIES
COLLOIDAL SILVER
SELECTIVE PHOTOMODIFICATION
CLUSTERS
LIGHT
Аннотация: Conditions for a change in the polarization selectivity of dips in the plasmon absorption spectra of fractal silver nanocomposites irradiated by pulsed laser radiation are studied. The energy thresholds of the polarization selectivity are evaluated, and the polarization and spectral threshold characteristics are compared. Mechanisms behind the correlation between the fractal structure of the nanocomposites, on the one hand, and their optical and photochromic properties, on the other hand, are discussed. (C) 2003 MAIK "Nauka / Interperiodica".
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16.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Markel V. A., Pustovit V. N., Karpov S. V., Obuschenko A. V., Gerasimov V. S., Isaev I. L.
Заглавие : Electromagnetic density of states and absorption of radiation by aggregates of nanospheres with multipole interactions
Место публикации : Phys. Rev. B: AMER PHYSICAL SOC, 2004. - Vol. 70, Is. 5. - Ст.54202. - ISSN 1098-0121, DOI 10.1103/PhysRevB.70.054202
Примечания : Cited References: 81
Предметные рубрики: DISCRETE-DIPOLE APPROXIMATION
ENHANCED RAMAN-SCATTERING
METAL FRACTAL CLUSTERS
OPTICAL-PROPERTIES
SELECTIVE PHOTOMODIFICATION
DISORDERED CLUSTERS
NUMERICAL-SIMULATION
SPECTRAL DEPENDENCE
PARTICULATE MATTER
LIGHT-SCATTERING
Ключевые слова (''Своб.индексиров.''): carbon--iron--palladium--silver--article--dipole--electromagnetic field--geometry--mathematical analysis--molecular interaction--nanoparticle--radiation absorption
Аннотация: We calculate the quasistatic electromagnetic density of states for aggregates of touching spheres, in particular, linear chains and computer-generated random fractal aggregates. Multipole moments with orders of up to L=64 are taken into account for random aggregates with the number of particles of up to N=100 and up to L=8000 for linear chains. Extensive comparisons with the dipole approximation and geometrical cluster renormalization method are performed. Extinction spectra are calculated for several metals and black carbon. Long wavelength electromagnetic properties of fractal aggregates are considered in details.
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17.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Zobov V. E., Popov M. A.
Заглавие : Tree growth parameter in the Eden model on face-centered hypercubic lattices
Место публикации : Theor. Math. Phys. - 2005. - Vol. 144, Is. 3. - P.1361-1371. - ISSN 0040-5779, DOI 10.1007/s11232-005-0165-z
Примечания : Cited References: 19
Предметные рубрики: BRANCHED POLYMERS
HIGH-TEMPERATURES
EXPANSION
CLUSTERS
SYSTEMS
TIME
Ключевые слова (''Своб.индексиров.''): eden model--number of lattice trees--monte carlo method--growth parameter--singular points of generating function--large-dimension expansion--face-centered hypercubic lattice--eden model--face-centered hypercubic lattice--growth parameter--large-dimension expansion--monte carlo method--number of lattice trees--singular points of generating function
Аннотация: In the Eden model, we investigate how the tree growth parameter depends on the space dimension d for face-centered hypercubic lattices. We find the first three terms of the 1/d-expansion for this parameter directly from the generating function without calculating the number of trees because the growth parameter is the reciprocal coordinate of the singular point of the tree generating function. The same growth parameter was calculated by computer experiment where the ratios between the numbers of trees without intersections and trees without restrictions in the dimensions 3, 4, 6, 8, and 10 were estimated by the Monte Carlo method on face-centered cubic lattices. The results of the two methods agree well. Comparing with the previously performed computer experiment for simple hypercubic lattices, we observe that the values of the singular exponents for the tree generating functions are close for two different types of lattices.
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18.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Karpov S. V., Gerasimov V. S., Isaev I. L., Markel V. A.
Заглавие : Local anisotropy and giant enhancement of local electromagnetic fields in fractal aggregates of metal nanoparticles
Место публикации : Phys. Rev. B: AMER PHYSICAL SOC, 2005. - Vol. 72, Is. 20. - Ст.205425. - ISSN 1098-0121, DOI 10.1103/PhysRevB.72.205425
Примечания : Cited References: 56
Предметные рубрики: SMALL-PARTICLE COMPOSITES
DIFFUSION-LIMITED AGGREGATION
OPTICAL-PROPERTIES
SELECTIVE PHOTOMODIFICATION
NUMERICAL-SIMULATION
DISORDERED CLUSTERS
ABSORPTION-SPECTRUM
PARTICULATE MATTER
NONLINEAR OPTICS
LIGHT-SCATTERING
Аннотация: We have shown within quasistatic approximation that the giant fluctuations of a local electromagnetic field in random fractal aggregates of silver nanospheres are strongly correlated with a local anisotropy factor S which is defined in this paper. The latter is a purely geometrical parameter which characterizes the deviation of local environment of a given nanosphere in an aggregate from spherical symmetry. Therefore, it is possible to predict the sites with anomalously large local fields in an aggregate without explicitly solving the electromagnetic problem. We have also demonstrated that the average (over nanospheres) value of S does not depend noticeably on the fractal dimension D, except when D approaches the trivial limit D=3. In this case, as one can expect, the average local environment becomes spherically symmetrical and S approaches zero. This corresponds to the well-known fact that in trivial aggregates, fluctuations of local electromagnetic fields are much weaker than in fractal aggregates. Thus, we find that, within the quasistatics, the large-scale geometry does not have a significant impact on local electromagnetic responses in nanoaggregates in a wide range of fractal dimensions. However, this prediction is expected not to be correct in aggregates which are sufficiently large for the intermediate- and radiation-zone interaction of individual nanospheres to become important.
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19.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Aver'yanov E. M.
Заглавие : Dimension of mesogenic molecules as atomic clusters
Место публикации : Phys. Solid State: AMER INST PHYSICS, 2005. - Vol. 47, Is. 2. - P378-389. - ISSN 1063-7834, DOI 10.1134/1.1866424
Примечания : Cited References: 19
Предметные рубрики: LIQUID-CRYSTAL CHEMISTRY
ORIENTATIONAL ORDER
TRANSITION
Аннотация: The problem regarding the mass dimension D of mesogenic molecules as atomic clusters is formulated and solved using computer simulation and analytical calculations. For a large number of compounds belonging to different chemical classes, it is shown that the cores of discotic lacunar (rodlike, lathlike) molecules forming nematic or columnar discotic (calamitic) phases have a fractional dimension 1 D-c 2 (D-c approximate to 1). The dependences of the dimension D-c on the symmetry, the conformation, and the structural-chemical features of the molecular core are determined. It is demonstrated that, in the region of side flexible chains in molecules of both types, the dimension D-ch can be either smaller or larger than unity, depending on the chain conformation. An analytical expression accounting for the results of numerical experiments is obtained for the dimension D-ch. (C) 2005 Pleiades Publishing, Inc.
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20.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Gorban A., Popova T., Zinovyev A.
Заглавие : Codon usage trajectories and 7-cluster structure of 143 complete bacterial genornic sequences
Разночтения заглавия :авие SCOPUS: Codon usage trajectories and 7-cluster structure of 143 complete bacterial genomic sequences
Место публикации : Physica A: ELSEVIER SCIENCE BV, 2005. - Vol. 353. - P365-387. - ISSN 0378-4371, DOI 10.1016/j.physa.2005.01.043
Примечания : Cited References: 46
Предметные рубрики: DNA-BASE COMPOSITION
ASYMMETRIC SUBSTITUTION PATTERNS
PROTEIN-CODING REGIONS
MICROBIAL GENOMES
GENE IDENTIFICATION
MARKOV-MODELS
G+C CONTENT
BIAS
PREDICTION
SELECTION
Ключевые слова (''Своб.индексиров.''): genome--cluster--codon usage--correlations--entropy--mean field--cluster--codon usage--correlations--entropy--genome--mean field--approximation theory--correlation methods--database systems--entropy--functions--genes--mathematical models--clusters--codon usage--genomes--mean field--bacteria
Аннотация: Three results are presented. First, we prove the existence of a universal 7-cluster structure in all 143 completely sequenced bacterial genomes available in Genbank in August 2004, and explained its properties. The 7-cluster structure is responsible for the main part of sequence heterogeneity in bacterial genomes. In this sense, our 7 clusters is the basic model of bacterial genome sequence. We demonstrated that there are four basic "pure" types of this model, observed in nature: "parallel triangles", "perpendicular triangles", degenerated case and the flower-like type. Second, we answered the question: how big are the position-specific information and the contribution connected with correlations between nucleotide. The accuracy of the mean-field (context-free) approximation is estimated for bacterial genomes. We show that codon us-age of bacterial genomes is a multi-linear function of their genomic G+C-content with high accuracy (more precisely, by two similar functions, one for eubacterial genomes and the other one for archaea). Description of these two codon-usage trajectories is the third result. All 143 cluster animated 3D-scatters are collected in a database and is made available on our web-site: http://www.ihes.fr/similar to zinovyev/7clusters. (c) 2005 Elsevier B.V. All rights reserved.
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