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1.
Opt Express ; 24(14): 16123-31, 2016 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-27410879

RESUMO

Temporal properties of Zernike modes are investigated for the case of light wave propagation through the non-Kolmogorov turbulence. The calculations are performed for the weak-turbulence conditions with constant turbulence parameters along the propagation path and taking into account the effects of the outer and inner scale of the turbulence. It is shown that the difference between effects produced by the Kolmogorov and non-Kolmogorov turbulence is getting smaller when the aberration order is growing up and when the outer scale magnitude is decreasing. Also it is shown that the correlation time of an aberration is decreasing with increasing of its order and with decreasing of spectral index.

3.
Appl Opt ; 38(19): 3985-92, 1999 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-18323873

RESUMO

A generalization of the method of random wave vectors [Appl. Opt. 36, 464 (1997)] that is suitable for a simulation of turbulence-induced anisoplanatic effects is proposed. A simulation of the cross-correlated phase fluctuations produced by two initially plane waves propagating through weak turbulence is considered. The variation of C(n)(2) along a propagation path and an effect of the finite outer scale of the turbulence are included in the simulation. The validity of the simulation method is verified by comparison of theoretical and simulated results. The simulation approach developed can be used in the problems related to adaptive optics, speckle inteferometry, guide stars, and imaging through turbulence.

6.
Appl Opt ; 37(21): 4544-8, 1998 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-18285908

RESUMO

The influence of the turbulence outer scale on the Strehl ratio obtained with low-order adaptive optics systems is examined by numerical simulation. The Karhunen-Loeve approach is used to generate wave-front samples. A method that allows construction of the outer-scale-dependent Karhunen-Loeve functions is described. It is shown that the Strehl ratio produced by a second-order adaptive optics correction (tip-tilt, defocus, and astigmatism) is affected quite strongly by the finite outer scale. For the higher-order correction, the effect under study is weak and appears only when the outer-scale magnitude becomes less than the aperture diameter. It is also shown that the finite outer scale has a positive effect on the Strehl ratio of the uncorrected long-exposure image.

7.
Mol Gen Mikrobiol Virusol ; (1-2): 3-7, 1992.
Artigo em Russo | MEDLINE | ID: mdl-1535689

RESUMO

The proteins associated with the ribosomal subunits having the molecular masses from 158 to 47 kDa were isolated from hyaloplasmic, nucleoid and membrane fractions of Escherichia coli MRE600 cells. The proteins are eliminated from 50S subunits of ribosomes by thrice washing with the 1 M ammonium chloride buffer. 50S subunit proteins were found to be immunologically related to the inner membrane proteins. The native 50S subunits of ribosomes possess the expressed ATP-ase activity, while the washed off subunits lose it completely.


Assuntos
Escherichia coli/metabolismo , Proteínas Ribossômicas/metabolismo , Adenosina Trifosfatases/metabolismo , Membrana Celular/metabolismo , Núcleo Celular/metabolismo , Eletroforese em Gel de Poliacrilamida , Focalização Isoelétrica , Ribossomos/metabolismo
8.
Artigo em Russo | MEDLINE | ID: mdl-6199046

RESUMO

The nucleotide composition of chromosome and plasmid DNA free of hybrid RNA isolated from resting Escherichia coli cells preliminary cultivated with the help of [14C] uracil has been studied. It has been established that DNA contains [14C]uracil side by side with adenine, thymine, guanine and cytosine. It confirms the presence of RNA fragments in the composition of bacterial DNA which are connected with it covalently.


Assuntos
DNA Bacteriano/análise , RNA Bacteriano/análise , Bacillus subtilis , Cromossomos Bacterianos/análise , Escherichia coli , Hibridização de Ácido Nucleico , Nucleotídeos/análise , Plasmídeos , Proteus vulgaris , Pseudomonas aeruginosa , Staphylococcus aureus
9.
Biokhimiia ; 45(8): 1481-7, 1980 Aug.
Artigo em Russo | MEDLINE | ID: mdl-6786373

RESUMO

It was found that the maximal disattachment of the ribosomes from the membrane structures is observed upon their treatment with 10 mM tris-HCl buffer, pH 7.5, containing 250 mM sucrose, 750 mM KCl, 5 mM magnesium acetate and 1 mM EDTA or puromycin. The most effective attachment of ribosomes to the membrane occurs in 10 mM tris-HCl buffer, pH 7.5, containing 5% sucrose and Mg2+. The increase of Mg2+ concentration in the medium from 0.5 mM up to 1 mM results in a 2-fold increase of the ribosomes bound to the membranes. The concentration of the ribosomal material involved in the reaction is very essential for ribosome binding to the membranes. The amount of ribosomes bound to the membranes increases proportionally to the increase of the ribosome concentration in the reaction mixture.


Assuntos
Escherichia coli/ultraestrutura , Ribossomos/ultraestrutura , Fracionamento Celular , Membrana Celular/ultraestrutura , Ácido Edético , Magnésio
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