A rapid synthesis of nanofibrillar cellulose/polystyrene composite via ultrasonic treatment.

A new method of the synthesis of nanofibrillar cellulose/polystyrene composite based on ultrasonic treatment of styrene emulsion in cellulose-water solution was elaborated. A new approach does not require additional heating and proposes a significantly faster synthesis (15 min, 45 °C) of the target composite compared to the methods described previously. A comprehensive analysis did not reveal any significant differences between mechanical, physical and biodegradable properties of the composite obtained by ultrasonic method and that one obtained by conventional thermal method, which requires much higher temperature (above 75 °C) and reaction duration (from 3 h).

Amplification of surface-enhanced Raman scattering by the oxidation of capping agents on gold nanoparticles.

Surface-enhanced Raman spectroscopy is a powerful analytical method, and is especially useful for the detection of nitrogen- and sulfur-containing organic substances in trace amounts. SERS substrates with high enhancement factors can be produced via the aggregation of gold nanoparticles, leading to the formation of 'hot spots' - regions of highest electric field intensity and Raman scattering enhancement. Thus, the availability of gold surfaces in 'hot spots' for the adsorption of analyte molecules strongly influences the enhancement factor of a substrate. We studied the kinetics of oxidation of dyes with hydrogen peroxide in the presence of citrate-capped gold nanoparticles and discovered the amplification of surface-enhanced Raman scattering, probably due to the oxidation of citrate ligands and the additional adsorption of dye molecules onto vacant spots on the gold surface. Maximum amplification was observed with 3% (v/v) hydrogen peroxide in the reaction medium. Under optimized conditions, model analytes can be detected at concentrations as low as 1 × 10-9 M, which is ten times lower than the detection limit without hydrogen peroxide addition.

[New strains of basidiomycetes that produce bioethanol from lignocellulose biomass].

Sixty six isolates were screened for ability of bioethanol production; dynamics of product accumulation and substrate utilization were investigated for two selected strains Trametes hirsuta MT-24.24 and Trametes versicolor IT-1. The strains' efficiency was evaluated as bioethanol production by 1 g biomass. Strain T. versicolor IT-1 producing over 33 g/L of the ethanol for 9 d was selected. Direct conversion of Na-carboxymethyl cellulose, microcrystalline cellulose and straw was shown with ethanol yields of 2.1, 1.6 and 1.7 g/L, respectively, for 9 d fermentation time.

[Hydrocarbons and fatty acid methyl esters in bacterial biomass before and after physicochemical treatment].

Hydrocarbons and fatty acid methyl esters were identified by chromatography-mass spectrometry in the extracts from the native biomass of bacteria: chemoorganoheterotrophic Arthrobacter sp. and Pseudomonas aeruginosa and chemolithoautotrophic Carboxydothermus sp. Ultrasound treatment of bacterial biomass and mild thermolysis were shown promote formation of a broad spectrum of hydrocarbons from bacterial biomass. The biomarker stigmastane belonging to the sterane group was found in P. aeruginosa biomass after thermolysis at 110 degrees C in an open vial. Alkane composition in P. aeruginosa biomass before and after thermolysis at 300 degrees C in a sealed container remained unchanged, indicating the possibility of preservation of hydrocarbons of bacterial origin in sealed layers under high temperature and elevated pressure.

[Submerged cultivation and chemical composition of Hericium erinaceus mycelium].

Submerged cultivation of Hericium erinaceus in various media was studied. The yield of the biomass was shown to depend mainly on the carbon source, whereas the content of water soluble polysaccharides depended mainly on the nitrogen source. The optimal medium composition provided the biomass yield of 21-23 g/l in 7 days. The biomass was characterized by the content of total protein, lipids and carbohydrates. In addition, the amino acid composition of the biomass was determined and shown to meet all the requirements of FAO/WHO concerning the amounts of essential amino acids (with exception of tryptophane). Oleinic and linoleic acids were identified as the main components of the fatty acids. Two water soluble polysaccharide fractions differing in solubility in aqueous ethanol were isolated and shown to contain rhamnose, fucose, xylose, glucose and galactose in different proportions. Vitamins B1, B2, B6, PP and E, ergosterol and coenzyme Q were also detected in the biomass of H. erinaceus.

[Submerged cultivation of Lentinus edodes strain with broad spectrum biological activity].

A highly potent strain of Lentinus edodes producing lentinomycin B, an erythadenin metabolite showing hypolipidemic activity, and biologically active water soluble endopolysaccharides was isolated. The optimum composition of the medium for the strain submerged cultivation was developed. The medium provided shorter period of the strain cultivation and a 2-fold increase of the biomass yield and production of the endopolysaccharides up to 21 g/l and 4.8 g/l of the culture fluid respectively. The total fraction of the water soluble polysaccharides isolated from the mycelium contained glucose, galactose, mannose, arabinose and xylose as the neutral monosaccharides. Glucose was the main monosaccharide. The procedure of the strain submerged cultivation provided production of several final substances during a single technological cycle.

[Comparative analysis of osteotomy methods in open setting of congenital hip dislocation in children]. / Sravnitel'nyi analiz sposobov osteotomi pri otkrytom vpravlenii vrozhdennogo vyvikha bedra u detei.

There is given an analysis of the treatment of 89 children (99 joints) with congenital femur dislocation, which were subjected to corrective osteotomy at the open setting by three different methods. There are shown the advantages of oblique osteotomy, proposed by the authors. There have been developed and substantiated the indications for application of oblique and transversal osteotomy of the femur.

[Isoniazid concentrations in the blood, resected lung tissue and the gallbladder bed in relation to the method of administration to pulmonary tuberculosis patients with stomach and liver diseases]. / Kontsentratsiia izoniazida v krovi, tkaniakh rezetsirovannykh legkikh i lozhe zhelchnogo puzyria u bol'nykh legochnym tuberkulezom s zabolevaniiami zheludka i pecheni v zavisimosti ot metoda vvedeniia.

The advisability of isoniazid administration in the form of ultrasonic aerosols in the treatment of patients with pulmonary tuberculosis and diseases of the gastrointestinal tract is shown.