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Monitoring of the level of different flammable liquids is examined, including that of petroleum products in high capacity tanks, as well as during pumping, at oil storage depots. The operating characteristics of most level measurement devices do not meet customer specifications in practice. Commercial accounting for petroleum products requires more precise measurements and more stable operation of the liquid level gauges set up for factory conditions and spark-explosion safe operation. The development of a spark-explosion-safe device with a hydrostatic fiber-optic liquid level sensor and a position-sensitive detector is validated. For continuous monitoring of liquid level, it is proposed that measurements be made of the displacement of the bottom of a bellows under the influence of the hydrostatic pressure created by a column of the liquid with automatic compensation of the change in the density of the liquid. Compensation is carried out with a small buoy with an optical triangulation sensor for small displacements installed in it with a position-sensitive detector. The use of a bellows for suspension of the buoy is justified theoretically. The operating principle of the fiber-optic liquid level sensor is described. The calculated absolute measurement error for the level of a petroleum product is less than ±1 mm. The spark-explosion hazard of the device is reduced because there are no wires in the measurement zone, so the proposed device can be used in different fi re-hazardous media with a corresponding spark safety level confirmed by certification.

The dephosphorization of a manganese oxide concentrate with an increased phosphorus content is experimentally studied by blowing a manganese-containing melt with carbon monoxide in the temperature range 1400–1560°C. The reaction of gaseous carbon monoxide with phosphorus oxide dissolved in a manganese-containing melt begins to develop. The dephosphorization leads to a substantial decrease in the phosphorus content in a manganese-containing melt. A new method for the dephosphorization of manganese-containing products is developed. The method has no analogs and makes it possible to involve domestic manganese ores in production.

Pseudomonas aeruginosa is a widely represented species of bacteria possessing of a pathogenic potential. This infectious agent is causing wound infections, fibrotic cystitis, fibrosing pneumonia, bacterial sepsis, etc. The microorganism is highly resistant to antiseptics, disinfectants, immune system responses of the body. The responses of a quorum sense of this kind of bacteria ensure the inclusion of many pathogenicity factors. The analysis of the scientific literature made it possible to formulate four questions concerning the role of biofilms for the adaptation of P. aeruginosa to adverse environmental factors: Is another person appears to be predominantly of a source an etiological agent or the source of P. aeruginosa infection in the environment? Does the formation of biofilms influence on the antibiotic resistance? How the antagonistic activity of microorganisms is realized in biofilm form? What is the main function of biofilms in the functioning of bacteria? A hypothesis has been put forward the effect of biofilms on the increase of antibiotic resistance of bacteria and, in particular, P. aeruginosa to be secondary in charcter. It is more likely a biofilmboth to fulfill the function of storing nutrients and provide topical competition in the face of food scarcity. In connection with the incompatibility of the molecular radii of most antibiotics and pores in biofilm, biofilm is doubtful to be capable of performing a barrier function for protecting against antibiotics. However, with respect to antibodies and immunocompetent cells, the barrier function is beyond doubt. The biofilm is more likely to fulfill the function of storing nutrients and providing topical competition in conditions of scarcity of food resources.

Vascular endothelial growth factor B (VEGFB) is a pleiotropic trophic factor, which in contrast to the closely related VEGFA is known to have a limited effect on angiogenesis. VEGFB improves survival in various tissues including the nervous system, where the effect was observed mainly for peripheral neurons. The neurotrophic effect of VEGFB on central nervous system neurons has been less investigated. Here we demonstrated that VEGFB promotes neurite outgrowth from primary cerebellar granule, hippocampal, and retinal neurons in vitro. VEGFB protected hippocampal and retinal neurons from both oxidative stress and glutamate-induced neuronal death. The VEGF receptor 1 (VEGFR1) is required for VEGFB-induced neurotrophic and neuroprotective effects. Using a structure-based approach, we designed short peptides, termed Vefin1-7, mimicking the binding interface of VEGFB to VEGFR1. Vefins were analyzed for their secondary structure and binding to VEGF receptors and compared with previously described peptides derived from VEGFA, another ligand of VEGFR1. We show that Vefins have neurotrophic and neuroprotective effects on primary hippocampal, cerebellar granule, and retinal neurons in vitro with potencies comparable to VEGFB. Similar to VEGFB, Vefins were not mitogenic for MCF-7 cancer cells. Furthermore, one of the peptides, Vefin7, even dose-dependently inhibited the proliferation of MCF-7 cells in vitro. Unraveling the neurotrophic and neuroprotective potentials of VEGFB, the only nonangiogenic factor of the VEGF family, is promising for the development of neuroprotective peptide-based therapies.

Results are provided a study of the structure, physical properties, mechanical properties, and long-term strength of a new heat-resistant, low-nickel, nitrogen-containing steel 40Kh25N12G4SABL and its modifications. Compared with those used currently in this field the new steel has a nickel content reduced by 40%, improved mechanical properties at room and elevated temperatures, and increased values for creep strength and heat resistance.

Aqueous solutions of guanylurea hydrogen phosphite (GUHP) have been synthesized. The temperature dependence of equilibrium GUHP concentration in water was obtained. The change in the density of aqueous GUHP solutions with a change in their concentration was investigated. The influence of the solution pH on the GUHP solubility in water in the temperature range of +25–45°C was analyzed. The crystallization range of monoclinic GUHP crystals, belonging to the sp. gr. Cc, was determined. GUHP crystals were grown using different methods, based on cooling or maintaining a constant temperature, with mixing aqueous solutions or without mixing. The properties of the grown crystals in the optical and THz ranges were investigated.

In the course of the study permeability of intestinal mucosa of chickens suffering from eimeriosis while treating them with various veterinary drugs, including probiotics, was evaluated. The simulation of a typical clinical picture of eimeriosis was carried out by oral administration of suspension with coccidial oocysts (1.6 × 105/head) using a probe. To create different forms and different intensity of inflammatory processes, chickens that received various anticoccidial preparations and probiotic strain Bacillus subtilis were infected with eimeria. According to the data from an autopsy, it was found that the use of a spore probiotic based on Bacillus subtilis and anticoccidial drugs containing robenidine hydrochloride and salinomycin had a positive protective effect when treating chickens from eimeriosis. A similar picture was observed when assessing permeability of intestinal mucosa as affected by bacteriophage, whereby permeability decreased with the use of probiotics and the above-mentioned active agents. In general, the decrease in productivity was significant in all groups. However, the effect of spore-based probiotics was quite pronounced against the background of eimeria polyresistance. In the situation where anticoccidial drugs are less effective, the use of a spore-based probiotic can have a noticeable protective effect. The effect of all anticoccidial drugs under study on the concentration of oocysts and the state of the mucosa was insignificant, which indicated polyresistance of different types of eimeria isolated from biological material to these drugs. The analysis of the intestinal mucosa integrity, based on the study of mucosa permeability to bacteriophages and a Johnson and Reid scoring procedure showed that a spore probiotic based on B. subtilis and anticoccidial drugs containing robenidine and salinomycin had the best protective effect against eimeriosis caused by field isolates of eimeria. When treating chickens suffering from eimeriosis caused by polyresistant forms of E. acervulina and E. tenella, it is advisable to use probiotics alongside with drugs based on robenidine and salinomycin.

We report on the creation and investigation of a new class of crystals for nonlinear optical applications in the NIR-THz range, requiring non-critical phase matching. A narrowband two-frequency THz radiation source is demonstrated. The spectral properties of THz radiation emitted via optical nonlinear rectification in a semiorganic molecular crystal guanylurea hydrogen phosphite (GUHP) are described in relation to the crystal axis orientation.

The monoclinic organic crystal of guanylurea hydrogen phosphite (GUHP) was considered. The absorption and refractive properties of an optically negative biaxial crystal were investigated. The terahertz time-domain spectroscopy under cryogenic conditions was carried out for observation of the temperature dependence of the phonon structure of GUHP crystal.

Objective:to assess the efficacy of fluorescence sentinel lymph node (SLN) detection with indocyanine green (ICG) in patients with cervical cancer.Materials and methods.We analyzed the results of examination and treatment in 80 patients with morphologically verified stage IA1–IIA1 cervical cancer. All patients underwent laparoscopic surgery with fluorescence SLN detection with ICG using a high-resolution infrared camera.Results.SLNs were detected in 78 out of 80 patients (97.5 %); the rate of bilateral SLN detection was 80.0 % (64 out of 80). SLNs were not identified in 2 patients only (2.5 %). The majority of SLNs (99 out of 176; 56.28 %) were located in the internal group of lymph nodes, near to the common iliac artery bifurcation. Eleven out of 80 patients (13.75 %) were found to have pelvic lymph node metastasis. SLN metastatic lesions were observed in 10 out of 80 patients (12.5 %), whereas only one participant had non-SLN metastasis. Therefore, the sensitivity of the fluorescence method with ICG was 98.75 %.Conclusion.Fluorescence SLN mapping with ICG in patients with stage IA1–IIA1 cervical cancer is an effective diagnostic method allowing SLN topical diagnosis, intraoperative restaging, and correction of the treatment strategy.

Highly concentrated dispersions of few-layer graphene stabilized by amphiphilic block copolymer Pluronic F-108 are obtained. According to transmission electron and atomic force microscopy, the thickness of the graphene particles is on average from one to ten layers and their lateral sizes vary from 150 nm to 1 μm. Using these dispersions, new chitosan-based film composites with the filler content up to 5 wt % are obtained; the electrical conductivity of these composites reaches 4.3 × 10–1 S/cm.

An experimental procedure has been developed for constructing p i –T diagrams (partial vapor pressure of the ligand-forming component–temperature) for luminescent metal complexes with symmetric organic ligands. The partial 8-hydroxyquinoline vapor pressure–temperature diagram has been constructed for tris(8-hydroxyquinoline)gallium electrophosphor (Gaq3) in the temperature range 300–617 K at 8-hydroxyquinoline vapor pressures 10–3–104 Pa, where the homogeneity ranges of different Gaq3 polymorphs have been determined. Structure-sensitive properties of crystalline materials can be tailored by changing synthesis conditions within the homogeneity range of a phase.

New composite materials based on polylactide and graphene, suitable for creating three-dimensional objects using the 3D printing technology, were prepared. Introduction of the nanoadditive into the matrix of the biodegradable polymer enhances the tensile strength of the materials by more than 57%. In addition, the composites exhibit high electrical conductivity, reaching 0.9 S cm–1 for the composite with 3 wt % filler, which determines the possibility of using them for the development of various electrotechnical devices and tissue engineering structures.

Hydrated lanthanum fluoride powders, both undoped, and doped with erbium and ytterbium fluorides (to a total content of 6–28 mol %), of the general formula RF3 · nH2O (n = 0.30 ± 0.01), crystallizing in the hexagonal system, were obtained by coprecipitation from aqueous solutions of the corresponding nitrates by the interaction with hydrofluoric acid. The dehydration is completed at 380°C. At 600°C, the concentrated solid solution decomposes to precipitate a phase with the structure of orthorhombic YF3. The efficiency of the upconversion luminescence of the powders, excited at a wavelength of 974 nm, is low.

Two dimensional (2D) materials such as graphene and functionalized hexagonal boron nitride (h-BN) supported copper catalysts (CuO/rGO, CuO/h-BN, Cu(0)/rGO, Cu(0)/h-BN, CuS/rGO and CuS/h-BN) were prepared, characterized and evaluated their catalytic activity for the synthesis of imidazo[1,2-a]pyridines via one pot three component reaction between 2-aminopyridine, aldehyde and terminal alkynes. The imidazo[1,2-a]pyridines are an imperative class of nitrogen ring containing heterocyclic compounds which has wide range of applications in medicinal chemistry and drug molecule production. The reported synthetic protocol provides a rapid access to substituted imidazo[1,2-a]pyridines with excellent yields. CuO/rGO nanocomposite material was found to be highly active catalyst for the aforementioned reaction. The advantages of our protocol for the preparation of imidazo[1,2-a]pyridines over other previously reported includes shorter reaction times, functional group tolerance, recyclable catalyst and additive-free.

Colloidal dispersions of MoS2 in DMF were obtained, and a procedure for the preparation of the fraction of particles with the size distribution 1.5 times narrower than that in the original dispersion was developed. It was shown that for the gradual centrifugation of dispersions with an increase in the acceleration from 126g to 2016g the average thickness of nanosheets decreased from 35 to 8 nm and the average lateral sizes decreased from 250 nm to a constant value of 160 nm. A linear dependence of the absorbance of the dispersions on the concentration of MoS2 was established.

For the first time the comparison of the theoretical and experimental data have shown that UV–vis absorption in the region of 600 nm in colloidal solution of NbS 3 can be described by the d-d electronic transitions to the antibonding molecular orbital. It is proved that the process leads to excitation of metal-metal bond.

The current ecological state of Haplic Chernozems has been studied in three Specially Protected Natural Areas (SPNAs) of the Steppe zone in South of Russia. It has been found that the content of organic matter, texture and elements content of soils depend on the period and conditions of reservation in the SPNA. In accordance with the content and reserve of organic matter, the thickness of the humus-accumulative (A) and humus (A + B) horizons and the supply with macro- and micronutrients, the Haplic Chernozems of the SPNAs under study can be arranged in the following series: Persianovskaya Reserved Steppe > Botanical Garden of the Southern Federal University > Reserved Fallow land “Priazovskaya Steppe”, which corresponds to the duration of their reservation periods. The Botanical Garden, which is located in the center of a megalopolis (Rostov-on-Don, Russia), has higher contents of lead in the upper horizon of Haplic Chernozem than other soils on the plots considered.

Highly concentrated dispersions of polyvinylpyrrolidone-stabilized graphene were prepared. Using transmission electron microscopy, it was found that the graphene particles consisted, on average, of one to four layers, with the lateral size of 50–400 nm. From these dispersions, new film composites of chitosan with the filler content up to 4 wt % characteristic of electrical conductivity as high as 1.9 × 10–2 S/cm were formed.

Amyotrophic lateral sclerosis (ALS) is a devastating incurable neurological disorder characterized by motor neuron (MN) death and muscle dysfunction leading to mean survival time after diagnosis of only 2–5 years. A potential ALS treatment is to delay the loss of MNs and disease progression by the delivery of trophic factors. Previously, we demonstrated that implanted mesoporous silica nanoparticles (MSPs) loaded with trophic factor peptide mimetics support survival and induce differentiation of co-implanted embryonic stem cell (ESC)-derived MNs. Here, we investigate whether MSP loaded with peptide mimetics of ciliary neurotrophic factor (Cintrofin), glial-derived neurotrophic factor (Gliafin), and vascular endothelial growth factor (Vefin1) injected into the cervical spinal cord of mutant SOD1 mice affect disease progression and extend survival. We also transplanted boundary cap neural crest stem cells (bNCSCs) which have been shown previously to have a positive effect on MN survival in vitro and in vivo. We show that mimetic-loaded MSPs and bNCSCs significantly delay disease progression and increase survival of mutant SOD1 mice, and also that empty particles significantly improve the condition of ALS mice. Our results suggest that intraspinal delivery of MSPs is a potential therapeutic approach for the treatment of ALS.

In the past few years, a lot of attention has been directed to the synthesis of nanosized transition metal chalcogenides and their composites with noble metal nanoparticles. Materials of this type demonstrate enhanced properties in energy storage, catalysis and surface enhanced Raman spectroscopy devices. Although layered transition metal dichalcogenides are well studied, some other chalcogenides, namely layered niobium trisulfide (NbS3) and quasi-onedimensional vanadium tetrasulfide (VS4), have received less attention by comparison. In this work, we synthesized nanocomposites based on 2D niobium trisulfide and 1D vanadium tetrasulfide with gold nanoparticles and investigated their morphology and phase composition by transmission electron microscopy and X-Ray diffraction.

The Mo–S phase diagram exhibits two stable compounds: well-recognized layered molybdenum disulfide MoS2 and less studied molybdenum sesquisulfide Mo2S3. Here, we build a theoretical framework for the exfoliation of Mo2S3 based on density functional theory calculations and further experimentally prove its dispersibility under ultrasonic treatment and demonstrate its potential for use in gas detectors. First, we report computational studies of both Mo2S3 exfoliation and molecular adsorption on the Mo2S3 surface. The calculations reveal the preferential direction for the fragmentation of the Mo2S3 crystal along the (01) plane and, likely, chemisorptive interaction of solvent molecules, such as H2O or DMSO, with the (01) Mo2S3 surface. Next, we experimentally study the sonication of bulk Mo2S3 samples in organic solvents and show that, indeed, they may be converted to colloidal nanosized sheets. Solid particles in the dispersions retain the initial Mo2S3 crystal structure and have the shape of plates with typical thicknesses of 5–30 nm and lateral sizes of 100–400 nm. Finally, we investigate the gas sensing properties of the Mo2S3 films deposited from the dispersions towards moisture gas and several representative volatile organic compounds.

The electronic structure and lattice parameters of several quasi-one-dimensional compounds–known VS4, NbCl4, and NbS3 and hypothetical NbS4 and VS3–are obtained using density functional theory. Comparative analysis of chemical bonding and charge distribution in all these compounds reveals the possible origin of the structural instability of NbS4 and VS3.

Semiconductor based CuS-rGO nanocomposite materials have drawn a considerable attention towards photodegradation of organic dye molecules due to the low band gap (∼2.5 eV) of CuS nanoparticles. Presence of reduced graphene oxide (rGO) in CuS-rGO nanocomposite induced synergistic effect between CuS and rGO sheets which led towards better photocatalytic degradation efficiency as compared to CuS nanoparticles (without rGO support) and rGO alone. In this study CuS-rGO nanocomposite was synthesized by a simple microwave irradiation technique and characterized by High resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Thermogravimetric analysis (TGA) and Photoluminescence (PL) spectroscopy studies. The synthesized nanocomposite behaved as efficient photocatalyst towards diazo Congo Red (CR) dye molecule under natural sunlight irradiation with a maximum degradation efficiency of 98.76%. Effect of initial dye concentration, catalyst loading, pH of the reaction medium and role of different inorganic ions as well as the amount of graphene content in the photocatalyst on photocatalytic degradation of CR dye molecule was investigated in this study. The present study also focussed on the effect of different inorganic ions on the surface potential of the photocatalyst and their effect on the degradation process.

Mutations in superoxide dismutase (SOD1) are the second most common cause of familial amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disease caused by the death of motor neurons in the brain and spinal cord. SOD1 neurotoxicity has been attributed to aberrant accumulation of misfolded SOD1, which in its soluble form binds to intracellular organelles, such as mitochondria and ER, disrupting their functions. Here, we demonstrate that mutant SOD1 binds specifically to the N-terminal domain of the voltage-dependent anion channel (VDAC1), an outer mitochondrial membrane protein controlling cell energy, metabolic and survival pathways. Mutant SOD1(G93A) and SOD1(G85R), but not wild type SOD1, directly interact with VDAC1 and reduce its channel conductance. No such interaction with N-terminal-truncated VDAC1 occurs. Moreover, a VDAC1-derived N-terminal peptide inhibited mutant SOD1-induced toxicity. Incubation of motor neuron-like NSC-34 cells expressing mutant SOD1 or mouse embryonic stem cell-derived motor neurons with different VDAC1 N-terminal peptides resulted in enhanced cell survival. Taken together, our results establish a direct link between mutant SOD1 toxicity and the VDAC1 N-terminal domain and suggest that VDAC1 N-terminal peptides targeting mutant SOD1 provide potential new therapeutic strategies for ALS.

There was considered spatial physicochemical model of secondary gas substances of gas emissions, which allows two parallel processes: the wind carrying of the primary substance and its transformation into a secondary substance. The proposed model allows us to predict the spread in the lower atmosphere layers of the secondary gas emissions of anthropogenic origin, in particular, secondary emissions of continuous running metallurgical complexes. There was presented the solution of spatial model of the source in an analytical of chemical kinetics method. As a result become available an analytical function of the distribution of secondary substances taking into account its formation, wind transport and “destruction” of secondary substances in the atmosphere. To confirm the adequacy of kinetic model there were compared calculation results obtained by numerical and analytical method for the same conditions of the task. Both proposed models give the same results, and which of them can be used to build the fields concentration of substances of secondary emissions in the outer zone of influence of large industrial enterprises.

A study is made of the temperature and concentration dependences for conductance of aqueous sodium decyl sulfate solutions. The nature of hydration of the decyl sulfate anion is discussed within the theories proposed by Samoilov, Gurikov, and Krestov. An analysis is performed of the influence of the hydration type on the critical micelle concentration. The analysis suggests that an increase in temperature stimulates micelle formation given that hydration is negative.

Currently, limited information is available on the enzymatic activities in ancient paleosols and permafrost, which are recognized as unique depositories of extant microorganisms. In this work, samples from buried and modern top Kastanozems (Haplic Calcisol), modern tundra (Gleysol) soils, and permafrost were tested for amylase activity based on hydrolysis of starch to low-molecular sugars that are important energy sources for microorganisms. Our study demonstrated the preservation of amylase in buried paleosols (300 and 2000 years old) and permafrost (15,000–60,000 years old). The enzyme activity in buried soils was 5–7 times lower than in top soils and did not significantly (P > 0.05) differ from permafrost and tundra soils. Exogenously added alkylresorcinols, valine, and glycine influenced amylolytic activity in soil and permafrost samples in the dose-dependent manner. The amylase response to stimulating concentrations of alkylresorcinols and amino acids was greater in buried paleosols (4.3–11.5-fold) than in top soils (1.9–3.8-fold) over the enzymatic activities in the controls. Positive response of soil amylase even to little changes in concentrations of the low-molecular-weight compounds may be important during recovery of biological activity of microorganisms. Results of this study contribute to a more complete evaluation of hidden biological potential of ancient soils and permafrost and are relevant to paleomicrobiology and soil biology.

The influence of bacterial-humus preparations based on Gumigel (Agrosintez Company) on the biological activity of soddy-podzolic soil polluted with Pb(CH3COO)2 and gasoline was studied in a model experiment. Some indicators of biological activity are shown to depend on soil pollution to different extents. The process of nitrogen fixation and the activity of dehydrogenase and phosphatase were mostly inhibited by Pb(CH3COO)2 and gasoline. Gasoline compared to Pb(CH3COO)2 inhibited the soil biological activity to a greater extent. The bacterial-humus preparations exerted a significant positive effect on the biological activity of the polluted soils manifested in the increase of the total number of bacteria and of the enzyme activity (1.5–5.0 times), in the intensification of nitrogen fixation and denitrification (3–8 times), as well as in the increase in the biomass of the plants grown (1.5–2.0 times). The application of bacterial suspensions of pure cultures or the microbial complex without the preparations of humic acids did not always give a positive effect.

Although many of the layered metal chalcogenides, such as MoS2, are well-studied, some other chalcogenides have received less attention by comparison. In particular, there has been an emerging interest in vanadium tetrasulfide (VS4), which displays useful properties as a component of hybrids. However, the synthetic methods and characteristics of individual VS4 are not yet well defined, and there is no report on its solution processability. Here we have synthesized VS4 by a simple and fast direct reaction between elements. Reinvestigation of the VS4 crystal structure yielded more precise atomic coordinates and interatomic distances, thereby confirming the crystallization of VS4 in the monoclinic C2/c group and its quasi-1D chainlike structure. As the chains in VS4 are only bonded by weak van der Waals forces, we further demonstrate that bulk VS4 may be ultrasonically dispersed in appropriate solvents to form colloids, similarly to the layered chalcogenides. VS4 particles in colloids retain their phase identity and rod-shaped morphology with lengths in the range of hundreds of nanometers. Isopropanol dispersion exhibited the highest concentration and stability, which was achieved owing to the repulsion caused by high negative charges on the edges of the particles.

Classical Li-ion battery technology is based on the insertion of lithium ions into cathode materials involving metal (cationic) redox reactions. However, this vision is now being reconsidered, as many new-generation electrode materials with enhanced reversible capacities operate through combined cationic and anionic (non-metal) reversible redox processes or even exclusively through anionic redox transformations. Anionic participation in the redox reactions is observed in materials with more pronounced covalency, which is less typical for oxides, but quite common for phosphides or chalcogenides. In this Concept, we would like to draw the reader's attention to this new idea, especially, as it applies to transition-metal polychalcogenides, such as FeS2 , VS4 , TiS3 , NbS3 , TiS4 , MoS3 , etc., in which the key role is played by the (S-S)2- /2 S2- redox reaction. The exploration and better understanding of the anion-driven chemistry is important for designing advanced materials for battery and other energy-related applications.

Possible application of tungsten dichalcogenides as gas-sensing elements is discussed in this paper. The experimental results on sensitivity of pristine and niobium doped WS2 and WSe2 to acetone and ethanol gases are presented. Polycrystalline powder specimens were obtained by high temperature solid-state synthesis from the stoichiometric mixture of pure elements. Two types of samples were studied: 1) tablets pressed at 1.5 GPa to form bulk samples and 2) thin films prepared from 35% ethanol-water colloidal dispersions by their filtration onto membrane filters (pore diameter is 20 nm). The electrical resistances of the samples were shown to be increased in the presence of ethanol and acetone gases at room temperature, thereby revealing positive response to reducing gases.

Effect of the antibiotics kanamycin and ampicillin on growth and phase variation of the populations of four strains of lactic acid bacteria (Lactobacillus sp. M67AT, L. casei MB, Enterococcus faecium M, and E. faecium M3185) was studied. The presence of antibiotics in the medium resulted in a dose-dependent decrease in viable cell numbers and in partial or complete substitution of the dominant S variant with the minor Sm and Sb variants. The variants differed in colony morphology, as well as in some physiological, biochemical, biotechnological, and probiotic characteristics. The Sm type variants of all strains exhibited the highest resistance to antibiotics. High production of exopolysaccharides was found in Sb variants of lactobacilli and in S variants of enterococci. The highest antibacterial activity was found in Sm variants of lactobacilli, especially in Lactobacillus sp. M76AT The latter is biotechnologically the most promising strain, since all variants fermented milk yielding the products with uniformly pronounced functional and organoleptic properties. These patterns are of importance for the understanding of the mechanisms of antibiotic resistance and for selection of the variants with desired properties, as well as for quality control of the lactic acid bacteria starter cultures.

General information on the oxygen metabolism of phagocytic cells, the role of active oxygen compounds in vital activities, the functioning of various cells, and the development of pathological processes is presented. A new method for the analysis of the oxygen metabolism of phagocytic cells using chemiluminescence (on a multiple Synergy 2 SLAD detector analyzer) is described. Some examples of chemiluminescence kinetics in patients with various surgical pathologies are given.

The effect of the extracellular peptide reactivating factor (RF) synthesized by Luteococcus casei on stress response of Escherichia coli cells subjected to UV irradiation was studied. For these studies, we constructed a test strain carrying the umuD-lacZ operon. The expression rate of this operon reflects the rate of SOS response. Protective effect of RF, defined as the number of cells retaining the colony-forming activity (CFU) after UV irradiation (49–1166 J/m2), was dose-dependent, species-nonspecific, and increasing with increase of the stress load. RF was demonstrated to possess the properties of a direct adaptogen: 15 min of preincubation with RF caused a 1.5–6-fold decrease in expression of the umuD SOS response gene in UV-treated cells, concurrently with a 1.2–7.5 times increase in the number of viable cells (those having retained their colony-forming activity). The probable mechanisms of the protective effect of RF are being discussed.

A ceramic with dense nanosize structure was obtained by conventional sintering of samples formed from nanosize Si3N4 powder with Al2O3 and Y2O3 additives by cold isostatic pressing. The microstructure and density of the ceramic obtained were investigated. The technological conditions for obtaining silicon nitride ceramic that give the optimal combination of fine-grain submicron structure and high density were determined.

Introduction Runx1, a Runt domain transcription factor, controls the differentiation of nociceptors that express the neurotrophin receptor Ret, regulates the expression of many ion channels and receptors, and controls the lamina-specific innervation pattern of nociceptive afferents in the spinal cord. Moreover, mice lacking Runx1 exhibit specific defects in thermal and neuropathic pain. We investigated whether conditional activation of Runx1 short isoform (Runx1a), which lacks a transcription activation domain, influences differentiation of neural crest stem cells (NCSCs) in vitro and in vivo during development and whether postnatal Runx1a activation affects the sensitivity to neuropathic pain. Methods We activated ectopic expression of Runx1a in cultured NCSCs using the Tet-ON gene regulatory system during the formation of neurospheres and analyzed the proportion of neurons and glial cells originating from NCSCs. In in vivo experiments we applied doxycycline (DOX) to pregnant mice (days 8–11), i.e. when NCSCs actively migrate, and examined the phenotype of offsprings. We also examined whether DOX-induced activation of Runx1a in adult mice affects their sensitivity to mechanical stimulation following a constriction injury of the sciatic nerve. Results Ectopic Runx1a expression in cultured NCSCs resulted in predominantly glial differentiation. Offsprings in which Runx1a had been activated showed retarded growth and displayed megacolon, pigment defects, and dystrophic dorsal root ganglia. In the neuropathic pain model, the threshold for mechanical sensitivity was markedly increased following activation of Runx1a. Conclusion These data suggest that Runx1a has a specific role in NCSC development and that modulation of Runx1a activity may reduce mechanical hypersensitivity associated with neuropathic pain.

In our study, we investigated the capacity of alkylhydroxybenzenes (AHB), which are microbial anabiosis autoinducers, for alteration of the enzymatic activity of the hen egg-white lysozyme, as well as the efficiency of hydrolysis of specific (peptidoglycan) and nonspecific (chitin) substrates catalyzed by lysozyme. AHB homologues (C7-AHB and C12-AHB), which differ in their hydrophobicity and effects in their interaction with lysozyme, were used as modifying agents. C7-AHB stimulated enzymatic activity within the whole range of concentrations used (10−7−10−3 M). More hydrophobic C12-AHB exhibited this ability only at low concentrations and inhibited fermentative activity at high concentrations, acting as a mixed-type inhibitor. Both AHB homologues caused changes in the hydrophobicity of lysozyme molecules. An increase in the affinity level between the C7-AHB-modified enzyme and the nonspecific substrate (colloidal chitin or cell wall polymers of Saccharomyces sp.) was observed, which manifested itself in the enhancement of the hydrolysis rate by 200–500% (as compared to the native enzyme). A significant effect on the efficiency of the lysozyme-catalyzed modifications of the substrate (peptidoglycan, colloidal chitin) structure as a result of its complexation with AHB was demonstrated. A stabilizing effect of C7-AHB and C12-AHB was revealed, which ensured a high level of activity of the AHB-modified enzyme (as compared to the control) after heat treatment (functional stability), as well as at nonoptimal temperatures of catalysis (operational stability). The biological significance of lysozyme modification with AHB and the practical aspects of its application are discussed.

The effect of hexylresorcinol (HR), a chemical analogue of microbial anabiosis autoinducers of the alkylhydroxybenzene (AHB) group, on the stability of biological membranes and monolamellar liposomes formed of egg phosphatidylcholine (ePC) was studied. According to spectrophotometry and electron microscopy studies of HR-loaded liposomes in the presence of a surfactant Tween 20, the critical ratio between HR and ePC for liposome preservation was found to be close to equimolar. The trends in HR influence on membrane structural organization and stability of liposomes were also confirmed in experiments on intact bacterial cells explaining non-species-specific effect of AHBs. The demonstrated high efficiency of AHB biocides may be used in material and equipment protection against biocorrosion.

The effect of NTPS inhibitor on the corrosion behavior of magnesium alloys with various contents of alloying components is studied. NTPS is found to be an effective corrosion inhibitor in the absence of energizing, but under the anodic polarization, it does not produce any noticeable effect on the self-dissolution process. Comparative analysis of the processes proceeding at the anodic dissolution of magnesium and electron-microscopic studies of the specimens showed that the dissolution is accelerated due to the active-surface development. A supposition that, under the effect of a constant anodic current, the development and formation of the magnesium surface relief takes place at the initial polarization stage is put forward.

The monitoring of poly(di-n-hexylgermane) (PDHG) optical spectra in a variety of structures ranging from a polymer film to nanosize polymer filled porous media was performed by optical spectroscopy in the temperature range from 5 to 250 K. The PDHG nanocomposites were fabricated by insertion of PDHG polymers into SBA-15 mesoporous silica and SiO2 porous films. Temperature dependence of the PDHG film fluorescence spectra shows that the polymer generally has disordered conformation while the random ordered segments behave as defects. The spectra of the composites correspond to the polymer chains with even less ordered segments and the aggregates of such chains. This is confirmed by the absence of the thermochromic transition in the composites contrary to the film. The difference between the optical spectra of the film and the composites is due to a decrease of both the intermolecular and exciton-phonon interactions in the composites. It was shown that the polymer chains in the SiO2 pores are more ordered. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

We present a study of fluorescence (5–250)K and FTIR spectra of poly(di-n-hexylsilane) incorporated into nanoporous silicas (MCM-41 and SBA-15 types) and SiO2 aerosil. It is shown that the essential local conformation change of the polymer chain occurs only for the polymer embedded into and oriented in small-diameter pores with a large number of Si–OH groups on the surface of the walls. The competition between the polymer-surface and the polymer-polymer interactions leads to the restructuring of a polymer incorporated into the large pores of SBA-15 where the separarate polymer chain having trans- and gauche-conformations as well as the aggregates can be found. The presence of the gauche-conformation is confirmed by the shift of CHa2 and CHs2 stretching vibrations and, additionally, by the redistrubution of their intensity with increasing the pore diameter.

Stereoisomers of thiacalix[4]arenes unsubstituted at the upper rim and containing four carbonyl fragments have been synthesized for the first time. Their structures were studied by 1D and 2D NMR spectroscopy, IR spectroscopy, and mass spectrometry. The complexation properties of the macro-cycles toward alkaline metal cations were estimated by the picrate extraction method. The absence of the preorganization effect in the case of the thiacalixarenes unsubstituted at the upper rim is the main reason for the sharp decrease in their extraction ability.

The monitoring of poly(di-n-hexylgermane) (PDHG) optical spectra in a variety of structures ranging from a bulk film to a nanosize polymer confined into a nanopore of SBA-15 was performed using the fluorescence and fluorescence excitation spectra in the temperature range from 5 to 240 K as well as the absorption and FTIR spectra at room temperature. The observed data were compared with those obtained for poly(di-n-hexylsilane). It was shown that PDHG film absorption and fluorescence spectra strongly depend on the polymer thickness and consist of a number of bands which were assigned to centers with different amount of trans- and gauche- conformers of the polymer chains. Conformations of the polymer chains found in a thin film and in a 10 nm pore are similar while differing from the conformations of a thick film. Optical spectra of the confined PDHG are blue-shifted relative to those of a thin film. The PDHG polymer chain conformation becomes disordered with the decrease of the polymer film thickness and the nanopore size from 10 to 6 nm.

Photoluminescence and photoluminescence excitation spectra of nanosize poly(di-n-hexylsilane) embedded in the SBA-15 with 6 nm diameter pore were investigated in the temperature range of 10–290 K. We clearly demonstrate the thermochromic transition at 265 K between trans- and gauche- conformations of an isolated polymer chains embedded in the nanoporous material. Existence of the polymer chain having trans-conformation in a separate pore of 6 nm diameter was prooved. The location and packing of the polymer chains in this pore was simulated using the quantum chemistry calculations in the cluster approximation. The investigation of the polarized luminescence dynamics of the nanosize polymer with pore diameters of 6 and 10 nm has shown that the polymer chains are aligned by embedding.

We have recently observed that co-culture of mouse and rat beta-cells with mouse boundary cap neural crest stem cells (bNCSCs) protected against inflammatory cytokine-induced beta-cell death, possibly via direct cadherinmediated cell-to-cell junctions. However, it has not been addressed whether also human beta-cells can be protected via this strategy. If possible it would be an important approach for development of new protocols for improved outcome of islet transplantation to Type-1 diabetes patients. The aim of this investigation was therefore to study the effect of bNCSC co-culture with insulin producing human EndoC-βH1 cells on cytokine-induced cell death. For this purpose GFP-positive bNCSCs were cultured together with GFP-negative human EndoC-βH1 cells in the presence of the cytokines IL-1γ (50 U/ml) and IFN-γ (1000 U/ml). Cells were then stained with propidium iodide and trypsinized for flow cytometry analysis. Analysis of propidium iodide fluorescence in GFP-positive and GFP-negative cells revealed that EndoC-βH1 cells died to a lower extent when co-cultured with bNCSCs than when cultured without bNCSCs. We also observed that EndoC-βH1 cells formed N-cadherin, but not E-cadherin junctions with the bNCSCs. The bNCSC cell population contained a large proportion of beta-tubulin expressing cells indicating neuronal differentiation. A protective function of the N-cadherin junctions was verified by the finding that a neutralizing N-cadherin antibody counteracted the effect of co-culture. We conclude that the interaction between human insulin producing cells and bNCSCs results in a lowered susceptibility of insulin producing cells to pro-inflammatory cytokines in vitro.

The high level of comorbidity of coronary heart disease (CHD) and depressive disorders and general aspects of their pathogenesis is an actual problem of modern research. Authors studied the content of cholesterol, platelet serotonin, platelet aggregation, activity of pro-inflammatory markers in CHD patients with comorbid depressive disorders.The study included 76 patients with CAD. The diagnosis of depressive disorder was set according to ICD-10, The Hamilton depression scales was used.Depressive disorders in CHD patients were associated with an increase in the activity of pro-inflammatory markers (IL-6 and TNF-α), and with high levels of low density lipoproteins. In patients with CAD and depressive disorders with high contents of platelet serotonin, the level of cholesterol was higher compared to those with low contents of serotonin. No significant differences in the functional platelet activity were identified in patients with CAD and comorbid depression compared to patients without mood disorders.Цель исследования. В настоящее время в связи с высоким уровнем коморбидности ишемической болезни сердца (ИБС) и депрессивных расстройств проводится поиск общих аспектов патогенеза этих заболеваний. Цель работы - изучение содержания холестерина липопротеинов, серотонина тромбоцитов и плазмы крови, агрегационной способности тромбоцитов, активности провоспалительных маркеров у больных ИБС с коморбидными депрессивными расстройствами. Материал и методы. Обследовали 76 больных ИБС. Пациенты обследовались психопатологическим методом и с помощью шкалы депрессии Гамильтона. Диагноз депрессивных расстройств устанавливался согласно критериям МКБ-10. Результаты и заключение. Установлено, что депрессивные расстройства у больных ИБС ассоциируются с повышением активности провоспалительных маркеров (ИЛ-6 и ФНО-α), а также высоким уровнем липопротеинов очень низкой плотности. У пациентов с ИБС и депрессивными нарушениями с высоким содержанием серотонина тромбоцитов общий холестерин выше, чем у лиц из той же когорты с низким его содержанием. У пациентов с ИБС и коморбидной депрессией не было выявлено различий в функциональной активности тромбоцитов по сравнению с аналогичными показателями у больных без нарушений настроения.

Magnetoresistance and magnetization measurements on pure DyMn 6 Ge 6 and low-doped Dy(Mn 6 Ge 6 ) 1− x (Fe 6 Al 6 ) x samples x ≤ 0.05 with the hexagonal HfFe 6 Ge 6 -type structure are used to investigate the connection between magnetoresistance and magnetization processes in these compounds. At room temperature, DyMn 6 Ge 6 shows negative magnetoresistance MR ( H ), which is related to a transition from a ferromagnetic helix state into a fan state in this compound. Below 100 K, positive MR ( H ) is found with a non-monotonic dependence in fields above 20 T. The anomalous behavior of MR ( H ) is explained by a sequence of transitions from conical helix to conical fan and a field-driven canting in the ferromagnetic Dy-Mn-subunits at higher fields. This transition transforming the ferrimagnetic fan into a ferromagnetic spin-flop state is discernible as a macroscopic metamagnetic behavior in the magnetization curves. For low substituted samples an increase of the specific resistivity and reduced magnetic ordering temperatures are found. Their MR ( H ) at high temperatures displays a similar negative behavior as the pure compound. The anomalous low-temperature magnetoresistance behavior is absent in the alloyed samples.