Ladder Polyphenylsilsesquioxanes and Their Niobium-Siloxane Composite as Coating Materials: Spectroscopy and Atomic Oxygen Resistance Study.

In order to expand the range of materials that can be used in outer space and in development of small spacecraft, ladder polyphenylsilsesquioxanes with different molar weights and the Nb-siloxane composites based on them were studied. The properties of the polymer films were studied, including tests in an oxygen plasma flow. Both initial and filled ladder polymers feature extremely low erosion coefficients in the region of 10 cm/atom O at a high fluence of atomic oxygen of 1.

Pervaporation and Gas Separation Properties of High-Molecular Ladder-like Polyphenylsilsesquioxanes.

This paper presents the results of studies on the pervaporation properties (for benzene/hexane mixtures) and gas permeability (for He, H, N, O, CO, CH, CH, and CH) of ladder-like polyphenylsesquioxanes (L-PPSQ) with improved physical and chemical properties. These polymers were obtained by condensation of -tetraphenylcyclotetrasiloxanetetraol in ammonia medium. The structure of L-PPSQ was fully confirmed by a combination of physicochemical analysis methods: H, Si NMR, IR spectroscopy, HPLC, powder XRD, and viscometry in solution.

A Versatile Equilibrium Method for the Synthesis of High-Strength, Ladder-like Polyphenylsilsesquioxanes with Finely Tunable Molecular Parameters.

A versatile equilibrium method for synthesizing ladder-like polyphenylsilsesquioxanes (L-PPSQs) with various molecular weights (from 4 to 500 kDa) in liquid ammonia was developed. The effect of diverse parameters, such as temperature, monomer concentration, reaction time, addition or removal of water from the reaction medium, on the polycondensation process was determined. The molecular weight characteristics and structure of the L-PPSQ elements obtained were determined by GPC, H, Si NMR, IR spectroscopy, viscometry, and PXRD methods.

Prevalence and Antibiotic Resistance of Carbapenemase-Producing Gram-Negative Bacteria in Saint Petersburg and Some Other Regions of the Russian Federation.

Carbapenemase-producing gramnegative bacteria, which hydrolyze most offi-lactams, including carbapenems, is of global health care system threat. The number of the known carbapenemases is constantly increasing, however only four types are widely distributed: NDM-type, KPC-type, OXA-48-type and VIM-type. The frequency of carbapenemase-producing Klebsiellapneumoniae in hospitals of Saint Petersburg reached 9.

[Effect of adaptive biocontrol sessions in the presence of strong professional skill].

Effect of adaptive biocontrol on efficiency of the operator possessing stable skills in simulating manual control of Soyuz hang-up and berthing to the International space station (ISS) was studied. Job quality was evaluated by the time, energy and precision parameters. The investigation used an ISS computer model and mock-ups of the board operating controls.

[Retention of the skill to perform adaptive bio-control of bioelectrical activity synchronization in the human brain cortex in an argon-nitrogen-oxygen atmosphere with various oxygen content].

The best method to prevent fire incident in space vehicles and other habitable pressurized modules is reduction of atmospheric oxygen concentration (hypoxia). Atmosphere doping with argon may ease tolerance of this hypoxia by humans. Mental performance in Ag-N2-O2 atmosphere with various oxygen content was assed by: retention of the skill to perform adaptive biocontrol (ABC) of bioelectrical activity synchronization in the frontoparietal and parietooccipital cortex (EEG); emotional and mental state (Luscher test); work successfulness (completion of PC games "Miner"and "Tetris").

[Professional selection and successful residency training in anesthesiology-resuscitation].

The professional carrier of 356 residents, the 1960-2007 graduates of the Saint Petersburg Medical Academy of Postgraduate Education, was studied to specify approaches to professional selection of anesthesiologists. Thirty (8.4%) graduates did not work as anesthesiologists at all.

[Individual styles of operator performance and their encephalographic correlates].

When in flight, cosmonauts are to resolve problems in the conditions of deterministic and stochastic disturbances. To a considerable degree successful problem resolution is dependent on interactions of the parietofrontal and parietooccipital areas of the right and left cortexes. The paper illustrates the relationship between the baseline state according to the Luscher test, productivity indices of activities involving two areas of the cortex, and spatial synchronization of their bio-potentials.

[Specific features of digestive function development in larvae of some salmonid fish].

We studied the activities of digestive enzymes responsible for the digestion of food carbohydrate and protein components in plant-eating fish at various stages of larval development. The activities of all digestive enzymes tend to rise during larval development. Species specific features of the alimentary canal functioning have been described.

[The search of antioxidants in plant root's extracts of the carline thistle].

The carrying out tests of water-extracts of carline thistle (plant pink, Caryophyllaceae) in Kazakhstan (extract 1) and gathered in the Primorye region (extract 2). The method of spectral and thin layer chromatography silicagel plates contain phenolys components. It is found out that both extracts contain the same bonds with the max, uptake of long waves lambda = 282 hm and lambda = 260 hm.

[The algorithm of quantitative evaluation of the human state with the help of the Lusher test].

A Lusher test-based algorithm of the quantitative evaluation of the ability to perform under the conditions of determinant and stochastic stimuli was developed and validated in experiments with volunteered subjects.

The properties of gamma-radiation and high-energy neutron fluxes in "MIR" station orbit.

The study of radiation background components in the near-Earth space is very important for different branches of space research, in particular for space dosimetry and for the planning of gamma-astronomy experiments. Detailed information on the neutral components (gamma-quanta, neutrons) of background radiation was obtained during the Grif-1 experiment onboard Mir orbital station (OS). The measurements of fluxes of 0.

[Biosynthesis of alkaline extracellular proteinases in Bacillus intermedius].

The conditions for growth and serine proteinase biosynthesis were studied in the batch culture of Bacillus intermedius. The synthesis of the enzyme was found to be inhibited by glucose and by the amino acid mixture and activated by the addition of organic compounds-casein and gelatin-to the medium. Inorganic phosphate in the medium increased the enzyme yield.

[The affinity binding of staphylococci with immobilized human plasminogen].

The phenomenon of the selective adhesion of staphylococci to immobilized human plasminogen was discovered and studied in the reaction of bacteriosorption. The study, made with S.aureus cells, strain Cowan 1, revealed that the degree of adhesion depended on the amount of immobilized protein and the time of its contact with bacterial suspension.

[The effect of the conditions for connective tissue formation during posttraumatic skin regeneration in rats on the adhesive properties of the epidermal cells].

A cicatrix formed in the process of posttraumatic skin regeneration is characterized by a higher cell adhesion power in the upper, and, especially, in the middle epidermis stratum. The cell adhesion power indices in these strata, and cell mitotic activity of basal epidermis stratum near the cicatrix depend on conditions of connective tissue formation in the wound defect. The effect of physiological solution and trypsin on the wound process results in a moderate rising of intercellular contact strength and in decreasing in the number of dividing basal stratum cells, while addition of ronidase solution results in a sharp rising of the corneous scale adhesion strength, and in establishing the straight correlation between this index and the speed of epidermocyte production.

[The effect of the treatment of skin wounds in rats with hydrolytic enzymes on the synthetic activity of the epidermocytes].

Epidermis cells synthetic activity was studied by a luminescent microscopy method. Different conditions of skin wound healing in intrascapular region were investigated on 84 rats-males. Daily effect of 0.

[The importance of the pyruvate test for the early detection of diabetes mellitus in a mass examination of the population].

The levels of carbohydrate metabolism were examined in 329 inhabitants of Lvov (age: from 6 to 68 years). Determination of the pyruvate level, pyruvate dehydrogenase activity of the blood on the 120 minute after carbohydrate meal allowed to establish in healthy persons four-modal levels of distribution of the content of pyruvate in the capillary blood. These levels correspond to normal tolerance to glucose, increased glucose tolerance (hyperinsulinism), potential glucose tolerance disorders (diabetic type).

[The implementation of a strategy for the primary prevention of diabetes mellitus].

A pyruvate test for glucose tolerance was used during prophylactic medical examination of 47 students and 27 children without risk factors, 54 students with risk factors, 31 patients with type I diabetes mellitus and 220 construction workers in order to test a new methodological basis for the strategy of primary prevention of diabetes mellitus. The investigations showed the presence in a general population of 3-modal distribution of a variant of the capillary blood pyruvate level on the 120th min. of a GTT according to physiological glucose tolerance, potential (prediabetic) and actual (diabetic) carbohydrate metabolic derangements.

[Methodologic approaches to the study of the effect of complex environmental factors on the population's health].

The purpose of the study was to assess the dynamics of complex pollution of urban and occupational environment, territory design, air and water contamination and acoustic regime being taken into account. The technique for calculating the total load on the population was used for environment description. It was based on actual contamination in relation to standard one and the time of its effect.

[Correlations between lysosomal enzymes and cyclic nucleotides during allergies in children].

Correlation between activity of beta-galactosidase, N-acetyl-beta-D-glucosaminidase and content of cAMP and cGMP was studied in lymphocytes and polymorphonuclear leukocytes obtained from 20 children with atopic form of bronchial asthma and 9 patients with dermorespiratory syndrome. Activity of the lysosomal hydrolases studied correlated distinctly with the content of cyclic nucleotides in the leukocytes and lymphocytes of children with bronchial asthma and dermorespiratory syndrome. The most distinct relationship was found between the eosinophilia, the enzymatic activity and the cGMP content in lymphocytes and neutrophils under conditions of dermorespiratory syndrome.

[Central hemodynamic characteristics of breast cancer patients following radical treatment].

Integral body rheography was used for evaluating central hemodynamics in breast cancer patients at various stages following radical treatment. A decline in basic parameters was registered within the first 2-3 weeks postmastectomy to be followed by a gradual return to normal. A correlation between blood circulation indexes and hemoglobin values was established.