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For the first time, the generalized results of complex experimental studies aimed at the development functional nanodispersed liquid lubricants with anomalously high magnetic properties are reported. Appropriateness is substantiated for the use of a dispersion medium based on organosilicon liquids in the production of magnetic lubricating oils of a new generation. Information necessary for choosing the dispersed magnetic phase is presented. An original approach to the fitting of surface-active substances intended to stabilize the colloidal structure of magnetic oils, taking into account their dielectric properties and the features of the effect exerted on friction, has been demonstrated. Recommendations are given concerning a preliminary choice of prospective additives and fillers for magnetic oil, and the efficiency of the action of additives under different operating conditions of friction units with magnetic oil is established. Technological features are described for the synthesis of lubricants based on polyethylenesiloxane PES-5 and chlorophenylsiloxane KhS-2-1VV containing nanosized magnetite. The lubricating properties of magnetic oils based on oligodiethylsiloxane and oligomethyl(chlorophenyl)siloxane under various friction conditions have been investigated and their specific features have been demonstrated. The effect of various additives and fillers exerted on the tribotechnical characteristics of magnetic oils is analyzed in detail. A different mechanism of the effect exerted by additives on the properties friction contacts lubricated with magnetic oil is revealed and described. According to the testing results for the magnetic oils, lubricant compositions most promising for practical use in friction assemblies have been determined. It has been established that the service lifetime of the new magnetic oil is comparable with transmission gear oils, for example, TM-5-18, and two or three orders of magnitude greater than that inherent in plastic lubricants.

Tracing transmission routes and identifying pathogen sources are important issues in preventive measures aimed at controlling human and animal infectious diseases. A fast and accurate method for bacterial strain identification (genotyping) allows a scientifically sound planning of preventive schemes. Despite the existence of numerous bacteri a genotyping techniques, there is still room for developing a unified typing approach that would be applicable to a variety of bacterial species. The aim is to develop a genotyping method allowing identification of E. colistrains circulating at Russian chicken farms. The method is based on the earlier proposed idea of double digestion and selective labeling of DNA restriction fragments (DDSL). Bacterial genomic DNA is simultaneously digested with two restriction enzymes and labeled with biotinylated deoxynucleoside triphosphates with the presence of DNA polymerase. The enzymes are chosen in silico for each bacterial species so that a limited number of DNA fragments are generated for subsequent separation in conventional agarose gel. After implementation of the study with E. coliisolates, adequate reproducibility and a high discriminatory power of the technique were demonstrated. This approach was previously applied to genotyping other pathogenic bacterial species. The advantages of the proposed technique are the short turnaround time of analysis and easy availability of reagents and equipment. Transmission of a pathogen among chicken within one farm and existence of slightly different E. coligenotypes in various organs of the same individual were observed. Bacterial isolates obtained from any organ except the intestine were suitable for genotyping. Chicken intestine contains endogenous E. colistrains, which hamper the interpretation of the genotyping data obtained for a set of isolates. Thus, our work demonstrates the potential of the DDSL method for genotyping field E. coliisolates in the context of molecular epizootology.

Abstract: A set of N-acyllactosylamine derivatives containing a terminal amino group in aglycons of various lengths (up to 16 atoms) and various hydrophilicities were synthesized. The aglycons were represented by di-, tri-, and pentapeptides containing glycine and serine residues and by aglycons containing fragments of tartaric acid or a tertiary amine.

The molecular organization and functional activity of porins isolated from the outer membrane (OM) of the Yersinia enterocoliticaand three phylogenetically close nonpathogenic Yersiniaspecies (Y. intermedia, Y. kristensenii, and Y. frederiksenii) cultured at 6–8°C were comparatively studied for the first time. The proteins were isolated in two molecular forms (trimeric and monomeric), and their spatial structures were characterized by the methods of optical spectroscopy, CD and intrinsic protein fluorescence. The studied porins were shown to belong to the β-structural proteins (they have 59–96% total β structures and 0–17% α helices). The spatial structures of the proteins were demonstrated to depend on the nature of the detergent used for solubilization. Unlike the enterobacterial pore-forming proteins, the porin trimers are less stable to sodium dodecyl sulfate (SDS). The spatial structures of the porins become more compact after the substitution of octyl β-D-glucoside for SDS: the content of β structures increases and the accessibility of Trp residues to solvent decreases. It was established with the use of the technique of bilayer lipid membranes that the functional properties of the porins are similar to those of the OmpF proteins of Gram-negative bacteria. Trimers are functionally active forms of the porins. Special features of the pore-forming activity of the Yersiniaporins were revealed to depend on the microorganism species and the value of the membrane potential.

Synthesis of PEi‐g‐PA12 with concentration of PEi 2–40 wt % was fulfilled in two different ways, as ring‐opening polymerization of LL and transamidation of linear PA12 in the presence of core PEi molecules. Both methods provide almost uniform materials. Obtained samples were characterized using different techniques: solution and melt viscosity, molecular weight and molecular weight distribution of star polymers and PA12 “arms” with different content of cores, as well as melt and glass transition measurements, were fulfilled. For clarification of PEi‐g‐PA12 structure and mechanism of grafting, bis‐ (hexamethylen)triamin and tris(2‐aminoethyl)amin were used as a model core molecules. Participation of not only the primary but also the secondary and tertiary amino groups in the formation of PEi‐g‐PA12 polymers (until 2–8 wt % of PEi content) have been established. At higher content of PEi (8–15 wt %), only primary amino groups of core molecules take part in grafting. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 2413–2422, 2005

A series of nitrogen-containing physiologically active compounds underwent smooth N-monoalkylation with N-bromoacetyl-β-glycopyranosylamines derived from N-acetyl-D-glucosamine and lactose. This reaction was demonstrated to be promising for the introduction of carbohydrate residues into heterocyclic compounds, viz., pyridine, imidazole, pyrimidinetrione, carboline, and piperazine derivatives, and into an amino acid, 5-hydroxy-L-tryptophan, which is unstable in alkaline media.

A star‐branched poly(ethylene imine)‐g‐polyamide 12 with a high concentration of primary amino end groups is an object of interest for future chemical modifications. In many cases, the concentration of primary amino groups, which are also the end groups of the polyamide 12 arms, and the concentrations of secondary and tertiary amino groups in a sample need to be known independently. Because of the difference in the reactivity of phthalic acid toward amino groups, its reaction with poly(ethylene imine)‐g‐polyamide 12 can be used for the analytical determination of these groups. With primary amino groups, phthalic acid forms phthalimido moieties, which are detectable by IR spectroscopy. The IR bands can be used for quantitative analysis with an appropriate calibration procedure. The concentration of primary amino groups can also be calculated as the difference between the concentration of all types of amino groups before the reaction with phthalic acid and the final concentration of amino and carboxylic groups after the reaction. The final concentration of the amino groups is equal to the concentration of unreacted tertiary amino groups after the reaction with phthalic acid anhydride. The difference between the final concentration of carboxylic groups and the initial concentration of carboxylic groups is equivalent to the concentration of secondary amino groups, which react with phthalic acid to form phthalamido acid moieties. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 556–563, 2005

An improved procedure for the synthesis of N-bromoacetyl-β-glycopyranosylamines from the corresponding β-glycosylamines was developed. The procedure is applicable to a wide range of derivatives of monosaccharides (hexoses, 2-acetamido-2-deoxyhexoses, hexuronamides, and 6-deoxyhexoses) and some disaccharides. For the derivatives of pentoses and 2-deoxyhexoses, the use of the corresponding β-glycosylammonium carbamates was found to be more convenient. N-Bromoacetyl-β-glycopyranosylamines derived from D-mannose, L-rhamnose, D-glucuronamide, 2-deoxy-D-arabino-hexose, 2-deoxy-D-lyxo-hexose, and melibiose were obtained for the first time.

New types of radical photoinitiators, based on azido and diazido structures, were compared to the reactivity of pure xanthone by using a photocalorimetry technique. Our results show that these photoinitiators are good candidates for radical polymerization. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1096–1101, 2003

The design and synthesis of data-acquisition systems (DAS) are considered, and parameters are given defining the costs of making such a system suitable for checking. Major elements and steps are identified in evaluating the DAS market, and the data are examined briefly from the point of view of a future investor.

Abstract: A convenient preparative procedure was developed for the synthesis ofN-glycyl-β-glycopyranosylamines, derivatives of monosaccharides (d-galactose,d-mannose,l-fucose, andN-acetyl-d-glucosamine) and disaccharides (lactose, melibiose, cellobiose, and maltose). These compounds were demonstrated to be useful for the preparation of glycoconjugates of biologically active compounds containing the carboxy group (nicotinic, orotic, kynurenic, and indoleacetic acids). Synthetic pathways were developed for conversions ofN-glycyl-β-glycopyranosylamines into derivatives containing the carboxy group with the use of malonic andl-tartaric acid derivatives.

Abstract: The dynamics of immune response to pore-forming protein isolated from the outer membrane ofYersinia pseudotuberculosis was studied on CBA and BALB/c mice. Experiments revealed a waveform curves of antibody levels to different porin forms reflecting the successions of immunoglobulin classes and superposition of independent responses to various antigen determinants. The dynamic of immune response to porin depends on the molecular form and dose of the antigen.

Abstract: Monoalkylation of amino acids of different structural types withN-chloroacetyl-glycosylamines was shown to be applicable for the preparation of glycoconjugates containing β-d-galactose,N-acetyl-β-d-glucosamine, β-d-mannose, and lactose residues. The glycoconjugates were synthesized from amino acids with secondary (sarcosine,l-proline) or primary (l-2- and 4-aminobutyric acids,l-tryptophan) amino groups as well as from various amino dicarboxylic acids (N-methyl-dl-aspartic,dl-aspartic,l-glutamic, anddl-2-aminoadipic acids). The derivatives obtained may be of interest for glycotargeting of physiologically active compounds of this series.

Absorption and fluorescence spectra of 2-aminoxanthone in solutions of different types at 77–350 Kwere studied. The existence of three bands (λ1 max= 417 nm, τ1= 14 ns; λ2 max= 528 nm, τ2= 13 ns; and λ3 max= 565 nm, τ3= 6 ns) in fluorescence of 2-aminoxanthone solutions has been established. It was shown that the first short-wave band was determined by deactivation of singlet excitation of an aminoxanthone molecule. The band with λ3 max= 565 nm (depending on the concentration) is connected with excimer-type aggregates, which are formed by aminoxanthone molecules grouped with the help of dipole molecules of solvent or by weak hydrogen bonds between aminoxanthone molecules. The emission in band λ2 max= 528 nm is caused by reversible changes in the 2-aminoxanthone molecule and probably is connected with an intramolecular proton transfer.

1.A new method for the preparation of 2-acetamido-2-deoxy-ß-D-glucopyranosylamine and 2-acetamido-4-0-(2-acetamido-2-deoxy-ß-D-glucopyranosyl)-2-deoxy-ß-D-glucopyranosylamine, based on the condensation of the corresponding N-acetamido sugars with NH4HCO3 in a saturated aqueous solution, was developed.2.A number of model glycopeptides with an N-glycosylamide carbohydrate-peptide bond were synthesized.

The methylamlde of O-(2-acetamido-2-desoxy-a-D-galactopyranosyl)-N-carbo-L-serine, the bond center in many glycoproteins, has been synthesized.

We have synthesized 2-acetamido-2-deoxy-3-O-[2-O-(a-L-fucopyranosyl)-ß-D-galactopyranosyl]-D-glucose — the determinant of blood group H substance.

The application of the CN algorithm to a new earthquake catalogue, for the period from 1932 to 1993, obtained by merging Romanian and U.S.S.R. data, allows us to monitor, on the intermediate time scale, the preparation of strong, intermediate-depth earthquakes in the Vrancea region. Four of the five strong earthquakes with a magnitude above 6.4 are predicted, the total duration of the Time of Increased Probability of the occurrence of an earthquake (TIP) occupies 21.7% of the time interval under consideration, i.e., about 2.5 years for each strong earthquake.

Abstract: Porine from the outer coat ofY. pseudotuberculosis is shown to be a species-specific agent of pseudotuberculosis. Porine-based enzyme immunoassay permits the detection of antibodies to all serological variants ofY. pseudotuberculosis. The possibility of diagnosing the disease in the early stages of infection is one advantage of the proposed method.

N-Chloroacetyl-ß-glycopyranosylimines were synthesized from various monosaccharide (hexoses, pentoses, deoxysugars, uronic acids, and sugar phosphates) and a disaccharide (lactose) byN-acylation of the corresponding ß-glycosylamines with chloroacetic anhydride in DMF In some cases, treatment of rnonosacc harides with NH3 in the presence of (NH4)2CO3 in MeOH or aqueous MeOH was more efficient than the methods previously described, as it gave ß-glycosylarnines in higher yields.

1.The reaction of esters of chloro- and bromonitroacetic acids (I) with NaHSO3, Na2SO3, and Na2S2O4, has resulted in the formation of Na-salts of esters of nitrosulfoacetic acid.2.In the reaction of (I) with Na2SO3 and a double quantity of NaHCO3, Na-salts of esters of halonitroacetic acid are formed, and the reaction of (I) with Na2S2O4 and NaHCO3 leads to Na-salts of esters of sulfoacetic acid.3.Physicochemical methods have been used to determine the spectroscopic characteristics and pKa of sodium salts of esters of nitrosulfoacetic acids and their low toxicity has been established.

1.We have prepared 1-amino-2-acetamido-1,2-dideoxy-D-glucitol, 1-amino-2-acetamido-1, 2-dideoxy-D-mannitol, and 1-amino-2-acetamido-4-0-(2-acetamido-2-deoxy-ß-D-glucopyranosyl)-1, 2-dideoxy-D-glucitol by reduction of the corresponding glycosylamines with NaBH3CN.2.Characteristic of 1-amino-2-acetamido-1,2-dideoxy-D-alditols is an N ? N migration of the acetyl group,

Conclusions An analysis has been made of periclase-chromite articles manufactured in accordance with combined technology at the Nikitov Dolomite and Panteleimonsk Refractory Plants.

Conclusions Converter slags based on a tar binder are located in the following order with respect to the increase in the degree of impregnation with slag: dolomite?dolomite-magnesite?magnesite. The greater degree of impregnation of magnesite refractories is due to recrystallization of the periclase grains, accompanied by an increase in their size, by saturation with magnesioferrite, and by dilatation of the reaction zone of the refractory.

Abstract: Efficient monoalkylation of a series of primary and secondary amines was demonstrated with the use ofN-chloroacetylglycosylamines derived fromd-glucose,d-galactose,d-mannose,N-acetyl-d-glucosamine, and lactose. The reaction was shown to be useful for incorporation of carbohydrate residues into physiologically active compounds. Glycoconjugates of some derivatives of piperazine, 2-phenylethylamine, tryptamine, and important biogenic amines (norephedrine, octopamine, dopamine) were prepared.

Abstract: The pore-forming proteins porins isolated fromYersinia pseudotuberculosis andY. enterocolitica outer membranes and purified were found, by means of enzyme-linked immunosorbent assays, to be genus-specific antigens. Antiporin antibodies were detected in rabbit antisera to the isolated proteins as well as to total outer membrane proteins and whole bacterial cells. Enzyme-linked immunosorbent and immunoblotting assays demonstrated an antigenic relatedness of porins from fiveYersinia species.

The application of the CN algorithm to a new earthquake catalogue, for the period from 1932 to 1993, obtained by merging Romanian and U.S.S.R. data, allows us to monitor, on the intermediate time scale. the preparation of strong, intermediate-depth earthquakes in the Vrancea region. Four of the five strong earthquakes with magnitudes above 6.4 are predicted. The total duration of the Time of Increased Probability (TIP) of the occurrence of an earthquake (TIP) occupies 21.7% of the time interval under consideration, i.e., about 2.5 years for each strong earthquake.

The proposed method of modifying a polyamide yarn is based on the formation of an interpenetrating polymeric network in its surface layer.

The dissociation of the protein-peptidoglycan (PPG) complex from the outer membrane ofYersinia pseudotuberculosis has given two protein fractions consisting predominantly of two polypeptides. A decrease in the electrophoretic mobility of the high-molecular-weight polypeptide on treatment with detergent and on heating is connected with conformational transitions: ß form ? a-helix. The polypeptides were obtained in the individual state by gel filtration on Bio-Gel. They are immunogenic for rabbits and exhibit antigenic relationship in the double immunodiffusion reaction in agar.

1.A study was made of the comparative stability of the O-glycoside carbohydrate-amino acid and carbohydrate-carbohydrate linkages of the O-maltoside and O-melibioside of some serine derivatives in both acid and alkaline media.2.The O-glycoside carbohydrate-carbohydrate linkage is more labile in acid medium. In alkaline medium the O-glycoside carbohydrate-amino acid linkage is cleaved by theß-elimination mechanism, while the stability of the O-glycoside carbohydrate-carbohydrate linkages is close to the stability of the same linkages in the corresponding disaccharides.

We synthesized the O-maltosides and O-melibiosides of N-carbobenzoxy-L-serine methylamide and L-serine methylamide.

Conclusions The hydration capacity of crushed fired dolomite with an apparent density of more than 2.90 g/cm3 is higher than that of uncrushed. However, even after storage for 30 days the weight increase resulting from hydration does not exceed 0.95%.

Conclusions Conclusions made by semidry pressing have excellent properties and a longer life than plastic-formed crucibles.

Abstract: Protective properties of two molecular forms of porin, a protein from the outer membrane ofYersinia pseudotuberculosis, are studied in animals infected with pseudotuberculosis and plague agents. The effect of adjuvant on the protective activity of porin is investigated. The possibility of using porin as a component of chemical antipseudotuberculosis vaccine is demonstrated.

The methylamide of 0-[2-acetamido-3-0-(2-acetamido-2-desoxy-i3-D-glucopyranosyl)-2-desoxy-ß-D-glucopyranosyl]-N-carbobenzoxy-L-serine was synthesized.

2-Acetamido-2-desoxy-3,6-di-O-(ß-D-galactopyranosyl)-D-glucose was synthesized.

Conclusions O-(2-Acetamido-2-desoxy-Β-D-glucopyranosyl)-N-Cbo-L-threonine methylamide (I) and O-[2-acetamido-2-desoxy-3-O-(Β-D-galactopyranosyl)-Β-D-glucopyranosyl]-N-Cbo-L-serine methylamide (II) were synthesized.