Stabilization of optical characteristics of DNA cholesteric liquid-crystalline dispersions

Abnormal optical properties of liquid-crystalline dispersions (phases) formed as a result of phase exclusion of double-stranded DNA and RNA from water-salt poly(ethylene glycol) solutions and X-ray parameters of these phases are compared. It is shown that the cholesteric packing of nucleic acid molecules is realized at the certain osmotic pressure of a solvent only. A comparison of the optical properties of liquid-crystalline phases (dispersions) to their X-ray parameters allows one to put forward a suggestion on various hydratation (fluctuation) regimes of the nucleic acid behaviour under the condensed phases formation and factors, influencing the mode of packing of these molecules in phases formed. It is shown as well, that immobilization of DNA cholesteric liquid-crystalline particles in the content of polymeric matrix is accompanied by the stabilization of these particles and, hence, their specific abnormal optical activity as well as by formation of particles having a structure, which corresponds to the "optically isotropic ordered liquid" without abnormal optical activity. Data on stabilization of the cholesteric structure of liquid-crystalline DNA dispersions by creation of polymeric chelate bridges between the neighbouring DNA molecules, fixed in the structure of liquid-crystalline dispersions, are shown.     

Primary structure of gene H of cattle plague virus strain K]

The paper analyzes the standard legal and methodological assurance of the quality and safety of animal food raw materials and foodstuffs (meat, meat products, fish, shellfish, crayfish and their processing products) by the parasitic purity rates according the requirements under the Russian Federation's laws "On Sanitary and Epidemiological Well-Being of the Population", "On Protection of Consumer's Rights", "On Certification of Products and Services", those of SanPiN, such as 2.3.2.560-96 "Sanitary Requirements for the Quality and Safety of Food Raw Materials and Foodstuffs" and 3.2.569-96 "Prevention of Parasitic Diseases in the Russian Federation".     

Homology and functional similarity of an hrp-linked pathogenicity locus, dspEF, of Erwinia amylovora and the avirulence locus avrE of Pseudomonas syringae pathovar tomato

The "disease-specific" (dsp) region next to the hrp gene cluster of Erwinia amylovora is required for pathogenicity but not for elicitation of the hypersensitive reaction. A 6.6-kb apparent operon, dspEF, was found responsible for this phenotype. The operon contains genes dspE and dspF and is positively regulated by hrpL. A BLAST search revealed similarity in the dspE gene to a partial sequence of the avrE locus of Pseudomonas syringae pathovar tomato. The entire avrE locus was sequenced. Homologs of dspE and dspF were found in juxtaposed operons and were designated avrE and avrF. Introduced on a plasmid, the dspEF locus rendered P. syringae pv. glycinea race 4 avirulent on soybean. An E. amylovora dspE mutant, however, elicited a hypersensitive reaction in soybean. The avrE locus in trans restored pathogenicity to dspE strains of E. amylovora, although restored strains were low in virulence. DspE and AvrE are large (198 kDa and 195 kDa) and hydrophilic. DspF and AvrF are small (16 kDa and 14 kDa) and acidic with predicted amphipathic alpha helices in their C termini; they resemble chaperones for virulence factors secreted by type III secretion systems of animal pathogens.     

Magnito-, electro- and echocardiography in detecting symptoms of the "hypertensive heart"

The study compared diagnostic potential of magnetocardiography (MCG), electrocardiography (ECG) and echocardiography (echo-CG) in 18 patients with arterial hypertension (AH). 32 healthy males served as control. Elements of MCG from normal subjects have been analyzed morphologically in 36 points of precordial leads. Left ventricular hypertrophy was registered at echo-CG, MCG, ECG in 11 (61%), 16 (84%) and 7 (34%) of the AH patients, respectively. Left atrial hypertrophy was discovered primarily by echo-CG and MCG. Defects in ventricular repolarization were recorded by MCg in 7 (39%) patients basing on MCG, echo-CG and rarely ECG signs of left ventricular hypertrophy. MCG is recommended as an effective tool in diagnosis of "hypertensive heart".     

Generalized Lévy-walk model for DNA nucleotide sequences

We propose a generalized Lévy walk to model fractal landscapes observed in noncoding DNA sequences. We find that this model provides a very close approximation to the empirical data and explains a number of statistical properties of genomic DNA sequences such as the distribution of strand-biased regions (those with an excess of one type of nucleotide) as well as local changes in the slope of the correlation exponent alpha. The generalized Lévy-walk model simultaneously accounts for the long-range correlations in noncoding DNA sequences and for the apparently paradoxical finding of long subregions of biased random walks (length lj) within these correlated sequences. In the generalized Lévy-walk model, the lj are chosen from a power-law distribution P(lj) varies as lj(-mu). The correlation exponent alpha is related to mu through alpha = 2-mu/2 if 2 < mu < 3. The model is consistent with the finding of "repetitive elements" of variable length interspersed within noncoding DNA.     

Spectroscopic features of laser-induced breakdown in water and aqueous solutions in ultrasonic field

It is established that the action of ultrasound leads to both sharp enhancement of the acoustic emission and increase in the intensity of spectral lines of laser-excited elements dissolved in aqueous salt solutions (NaCl, NaHCO₃, CaCl₂), which provides a new method of combined laser–ultrasonic spark spectroscopy. The task of synchronization of the acoustic and optical emission has been solved, which reveals dependence of the intensity of spectral lines on the phase of ultrasonic wave action.     

Determination of impurities in germanium tetrafluoride by IR spectroscopy and gas chromatography

Using high-resolution Fourier-transform IR spectroscopy and gas chromatography, we have identified more than 20 impurity species, in concentrations from 10⁻¹ to 10⁻⁵ vol %, in GeF₄ samples of different isotopic compositions. The germanium tetrafluoride samples are shown to contain C₁–C₄ hydrocarbons; hydrogen, carbon, silicon, and sulfur fluorides; fluorogermanes; fluorosilanes; and carbon and nitrogen oxides.     

OAO Uralmashzavod software for the simulation of solidification and mild compression

Software for simulating complex technological processes in the continuous casting of steel has been developed. Cristall (Cristall 2D, Cristall 3D), Dinamika (Dinamika-DSVO), and Cristall-Pora software permits the calculation of the temperature fields and phase composition of steel in offline and online modes and hence may be used in the predesign, design, debugging, and operation of industrial continuous-casting systems. In addition, Cristall-Pora software permits calculation of the hydrodynamic processes in the two-phase zone and accordingly may be used in the development of mild-compression equipment. Practical examples are presented.     

High-temperature thermal and X-ray diffraction studies, and room-temperature spectroscopic investigation of some inorganic pigments

Inorganic Cr- and Mn-containing pigments of different structural types were investigated by high-temperature and spectroscopic methods. The differential scanning calorimetry in the temperature interval 298-1723 K was applied to measure temperatures of phase transition and melting of the studied compounds. High-temperature X-ray diffraction in the range 298-1173 K was used for the determination of the thermal expansion coefficients for the first time. Factor group analysis was used to predict general vibration modes of pigments and determine the activity of these vibrations in Raman and IR spectra, the Assignment of bands in Raman, IR and diffuse reflectance spectra was undertaken.