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Relevance: One of the most common problems in modern caries prevention is the development of techniques to increase tooth resistance to the effects of cariogenic factors. Therefore, research is needed to study the chemical composition of tissues like teeth and body fluids surrounding the tooth to prevent demineralization process. The purpose of determining the effectiveness of work- and correlation relationship between endo saturation exogenous methods oral liquid mineral complexes., Material and Methods: In 95 patients analyzed the chemical composition and structure of the oral fluid by IR spectroscopy. For the collection of IR spectra used Verteh-70 spectrometer ('Bruker', Germany) and the prefix of frustrated total internal reflection PLATINUM ATR diamond prism., Results and Discussion: A correlation between the use of endogenous and exogenous methods of caries prevention, in favor of the former, as well as changes in the mineral-organic and phosphate-carbon ratio in the dry residues of oral fluid.

It was found that ants significantly affect the physiological activity and functional diversity of soil microbial communities, and redistribution of biophilic elements (C and N) down through the profile occurs in anthills compared to the control soil, as well as their accumulation in the underground part of the ant nests. A high urease activity was revealed in ant nests and ants. Functional dissimilarities of bacterial communities in all studied objects were determined by the miultisubstrate test.

This study is devoted to the investigation of possibility to use the total organic carbon as regulated index in drinking water as well as to the issues of hygienic regulation and harmonizing this index with the standards of other countries. Basing on the results of 3 years lasting investigation carried out by Municipal Unitary Enterprise "Vodokanal" of Yekaterinburg city permits to propose as the most informative and reliable index of the presence of organic substances in drinking water the content of total organic carbon in comparison with currently regulated permanganate oxidability, chemical and biochemical oxygen consumption.

The effect of southern (Microtus rossiaemeridionalis) and bank (Clethrionomys glareolus) voles on the biological activity of soddy-podzolic soil and culturozem has been studied. To estimate this effect, the activity of nitrogen and carbon transformation in the soil taken from the paths and different chambers of the holes of these rodents, as well as from the control plots where there were no voles, has been determined. The contents of organic carbon and nitrogen in the soil have been found. The parameters of functional diversity of the microbial community of soil have been studied. It has been noted that the effect of voles on the biological activity of the above soils manifested itself in increased intensity of aerobic and anaerobic destruction of organic matter and changes in the parameters of functional diversity of the microbial community of soils.

The role of ground fires in transformation of organic substances in the ground cover of larch stands in the permafrost zone of Central Siberia was studied, as was the postfire restoration dynamics of organic substances. Ground fires lead to a considerable decrease in concentrations and resources of organic carbon and its individual fractions in the ground cover, and restoration takes many decades.

The stock and structure of organic substances in the pine tree plantations on the overburden dumps of open-cut coal mines in Middle Siberia have been determined. It has been shown that the forming forest biogeocenoses differ from the natural phytocenoses and soils of the forest landscapes in the structure of the carbon pool and its distribution between the vegetation and soil components. In artificial forest ecosystems, the bulk of the plant component is accumulated in the aboveground part of the forest stand (40-59%). The aboveground grass cover contains only 0.1-1.4% of the total phytomass stock of the ecosystem. The annual accumulation of organic substances in the initial soils amounts to 0.28-1.45 t/ha.

The data from scientific publications on excretory activity of herbs root endings were analyzed, along with the data on the role of polyvalent metals cations in stabilization of humus substances (HS) of soil organic mineral complex. On the base of the analysis a working hypothesis was proposed considering root endings influence on fractional composition of soil organic components. To detect the changes taking place in soil HS, the chromatographic fractionation method was chosen. The soil aggregates stuck to root endings of germinating barley seed were washed off, and the washouts were used as the samples for the analysis. The soil from the weighed portion was dissolved directly with extenuating concentrations of LiCl and Li2SO4 alkaline solution. The fractionation was carried out in a chromatographic column. Some changes were detected in optical density of chernozem and dark-grey forest soil leached out after 1-2 days of barley seeds germination. Besides, the experiment showed that the content of organic carbon in HS changes as well.

The ability of 12 Pseudomonas putida and Pseudomonas fluorescens strains for growth in the tap water has been studied. All of them grew well in pasteurized Kyiv tap water at 500 colony-forming units--CFU/ml inoculum reaching the maximal titre 1.7 x 10(4)-4.6 x 10(6) CFU/ml after 240 hours of incubation. The most intensive growth was observed in strain P. putida UCM B-143, capable to assimilation of 84 different sources of carbon nutrition. The linear dependence between strain 143 growth and acetate carbon concentration in the interval of 10 to 60 microg/l has been demonstrated in deionized water with addition of necessary mineral salts; its yield was 4.5 x 10(6) CFU/microg of assimilable acetate carbon (AOC). Determination of AOC of water using standard methods, standard strain P. fluorescens UCM B-385 (P17, ATCC 49642) and selected strain P. putida B-143 gave the similar values of AOC quantities in the Kyiv tap water (536 and 600 microg of AOC in 11, accordingly). Viability of strain 143 grown in the artesian water decreased more quickly than that of the standard strain which is possibly connected with origin of both cultures: strain 143 was isolated from wheat rhizosphere while strain P17--from the drinking water.

Nitrogenase activity, the abundance of diazotrophic bacteria, the structure and functional characteristics of the complex of microorganisms, and the content of nitrogen and carbon were determined in the contents of the gastrointestinal tract of the European beaver. A high nitrogen-fixing activity in the large intestine correlated with an increase in nitrogen content in the chyme upon its transfer over the gastrointestinal tract. It is assumed that microbial nitrogen fixation plays a major role in nitrogen nutrition of the European beaver.

Changes in the composition of wood organic matter in dead-standing spruce and larch trees depending on the period after their death have been studied in the north of Central Siberia. The period after tree death has been estimated by means of cross-dating. The results show that changes in the composition of wood organic matter in 63% of cases are contingent on tree species. Wood decomposition in dead-standing trees is accompanied by an increase in the contents of alkali-soluble organic compounds. Lignin oxidation in larch begins approximately 80 years after tree death, whereas its transformation in spruce begins not earlier than after 100 years. In the forest-tundra of Central Siberia, the rate of wood organic matter transformation in dead-standing trees is one to two orders of magnitude lower than in fallen wood, which accounts for their role as a long-term store of carbon and mineral elements in these ecosystems.

Carbon stocks and accumulation rates in humus and peat horizons of the contiguous soil series of forest and bog ecosystems have been studied in the Central Forest State Biosphere Reserve (CFSBR, Tver region). Upland soil types (soddy podzolic, brown, and white podzolic) have been compared to waterlogged (peaty gley podzolic and peaty gley) and bog soils differing in trophic status, including those of raised, transitional, and lowland bogs. The results show that carbon stocks in mineral soils are many times smaller than in waterlogged soils and an order of magnitude smaller than in bog soils. Mineral and bog soils are characterized by similar rates of carbon accumulation averaged over the entire period of their existence. The highest rate of carbon accumulation has been noted for the soils of waterlogged habitats, although this process may be periodically disturbed by fires and other stress influences.

The content of microbial biomass (MB) was determined in samples of gray forest, chestnut, and tundra soils with different physicochemical properties (0.4-22.7% Corg; 8.4-26.8% silt particles; pH 4.3-8.4) by the methods of substrate-induced respiration (MB(SIR)) and direct microscopy (MB(M)). The samples of two upper soil layers, 0-5 and 5-10 cm (without plant litter), from different ecosystems (forest, forest shelter belt, meadow, fallow, and arable land) and elements of relief of interfluvial tundra (block/upper land plateau, depression between blocks) have been analyzed. The content of microbial biomass in the 0-5-cm soil layer was 216-8134 and 348-7513 microg C/g soil as measured by the methods of substrate-induced respiration and direct microscopy, respectively. The MB(SIR) and MB(M) values closely correlated with each other: r = 0.90 and 0.74 for 0-5 and 5-10 cm, respectively. The average MB(SIR)/MB(M) ratio was 90 and 60% for 0-5 and 5-10 cm, respectively. The portion of microbial carbon in total organic soil carbon was, on average, 4 and 3% (SIR) and 5 and 7% (direct microscopy) for 0-5 and 5-10 cm, respectively. Possible reasons for the differences between MB(SIR) and MB(M) values in the soils under study are discussed.

The carbon content of microbial biomass and the kinetic characteristics of microbial respiration response to substrate introduction have been estimated for chernozem soils of different farm lands: arable lands used for 10, 46, and 76 years, mowed fallow land, non-mowed fallow land, and woodland. Microbial biomass and the content of microbial carbon in humus (Cmic/Corg) decreased in the following order: soils under forest cenoses-mowed fallow land-10-year arable land-46- and 75-year arable land. The amount of microbial carbon in the long-plowed horizon was 40% of its content in the upper horizon of non-mowed fallow land. Arable soils were characterized by a lower metabolic diversity of microbial community and by the highest portion of microorganisms able to grow directly on glucose introduced into soil. The effects of different scenarios of carbon sequestration in soil on the reserves and activity of microbial biomass are discussed.

The influence of tamarisk (Meriones tamariscinus) and midday (M. meridianus) gerbils on soil biological activity in the Chernye Zemli, Kalmykia, was studied. Nitrogen fixation, denitrification, and CO2 emission were measured in soil samples from different parts of gerbil burrows. Functional biodiversity of the microbial community was evaluated using multisubstrate testing and comparison of bacterial group composition in samples from gerbil burrows. The impact of gerbils on soil biological activity was mediated by the changes in the group composition of microorganisms.

Recolonization of defaunated soil by springtails as well as by gamasid and oribatid mites and the changes in organic matter content of soil were studied in the northern taiga. After a one-year exposure in gauze bags (1.7 mm mesh), the abundance of microarthropods was higher but the number of species was lower compared to the surrounding soil. Large surface and litter forms did not colonize the samples, while the number of small and/or soil forms was higher. Soil samples inaccessible for microarthropods (0.15 mm mesh) were depleted of organic carbon compared to both surrounding soil and recolonized samples. The content of humic and fulvic acids was higher in the samples inaccessible to microarthropods. Humification processes prevailed in soils in the absence of microarthropods.

Microbiological and biogeochemical investigations of the processes of methane production (MP) and methane oxidation (MO) in the coastal waters and littoral of the Kandalaksha Bay of the White Sea were carried out. The studies were conducted in the coastal zones and in the water areas of the Kandalaksha Preserve, Moscow University White Sea Biological Station, and Zoological Institute (RAS) Biological Station in August, 1999, 2000, and 2001 and in March, 2001. The rate of CO2 assimilation in the shallow and littoral sediments was 35-27800 microg C/(dm3 day) in summer and 32.8-88.9 microg C/(dm3 day) in winter. The maximal rates of MP were observed in the littoral sediments in the zone of macrophyte decomposition, in local depressions, and in the estuary of a freshwater creak (up to 113 microl/(dm3 day)). The maximal level of MO was observed in the shallow estuarine sediments (up to 2450 microl/(dm3 day)). During the winter season, at the temperature of -0.5 to 0.5 degrees C, the MP rate in the littoral sediments was 0.02-0.3 microl/(dm3 day), while MO rate was 0.06-0.7 microl/(dm3 day). The isotopic data obtained indicate that the C(org) of the mats and of the upper sediment layers is enriched with the heavy 13C isotope by 1-4 per thousand as compared to the C(org) of the suspension, comprised on 33.5-34.3% of phytoplankton. A striking difference was found between the levels of methane emission by the typical littoral microlanscapes. In fine sediments, the average emission was 675 microl CH4/(m2 day), in the stormy discharge stretch sediments it was 1670 microl CH4/(m2 day), and under the stones and in silted pits, 1370 microl CH4/(m2 day). The calculation performed with consideration of the microlandscape areas with a high production allowed the CH4 production of 1 km2 of the littoral to be estimated as 192-300 1 CH4/(km2 day).

Quantitative data on the nutritional requirements of microorganisms are necessary to predict the behavior of bacterial populations and to control their cultivation. The requirements of the R, S, and M dissociants of Pseudomonas aeruginosa for carbon, nitrogen, and phosphorus were derived from the results of 88 cultivation experiments. For each of the dissociants, we derived a coefficient that relates the optical density and the number of cells in the dissociant culture, determined the time when the cultures entered the stationary growth phase, studied cultural changes induced by transfer to the stationary phase, and determined what nutrients limit the growth of particular dissociants. The nutritional requirements of the dissociants are discussed in relation to our earlier data.

The dynamics of spectral and kinetic properties of alkali-soluble humic substances in the gray forest soil were studied in the course of its incubation with NH4H2PO4 (44.5 mg P per 100 g soil) for seven days, one year, and three years. The results provided evidence for consistent changes in the energy state of electrons in the functional groups of humic molecules extracted from the phosphorus-enriched soil. The structure of these molecules markedly changed by the end of the experiment, which was manifested in the increased number of coupled chromophores (due to the formation of additional C=C bonds) and the accumulation of new strongly polar functional groups (P=O). These changes provided for an increased solubility of soil humus in 0.1 N NaOH, higher saturation of dissolved humic substances with metals, and a different pattern of the distribution of carbon, metals, and phosphorus between the fractions of humic and fulvic acids.

Out of the whole number of impurities (more than 30) detected in aerosol discharge of TES using Cheliabinsk mine coal only for 16 of them MACs for the air of residentials areas or tentative safe exposure levels were established. The most important from the hygienic point of view are dust, aluminum, iron, manganese, barium, vanadium and lead.

The rate of molecular nitrogen fixation was determined in bottom grounds of three Estonian lakes and the Rybinsk water reservoir in the summer of 1977--1978. Certain species of nitrogen fixing bacteria were found to be confined to lakes of certain trophic type. Ecological niches with the mass growth of Clostridium pasteurianum, Azomonas agilis and Clostridium butyricum were detected in the sediments of eutrophic lakes. Ecological niches of Az. insignis and Cl. acetobutylicum occur in polyhumic lakes. Ecological niches for the nitrogen fixing microaerophilic organisms Methylosinus trichosporium, M. sporium and Mycobacterium flavum can be found in the sediments of water reservoirs of any trophic type. The important ecological factors which favour the growth of microflora with a high rate of molecular nitrogen fixation in bottom grounds are as follows: a sufficiently high temperature, a weakly alkaline reaction, the presence of oxygen in the water near the bottom, and the ratio of organic carbon to total nitrogen about 10--11. The destruction of organic substances in such sediments involves both aerobic and anaerobic microflora, and Cl. butyricum is abundant among nitrogen fixing microorganisms.

Cultivation of Candida tropicalis IBEM 303 without thermostatic regulation on n-alkanes results in an increase of the temperature in the fermenter to supraoptimal values and to the linear growth of the culture without distinct differentiation according to the growth phases. The cells grown at supraoptimal temperature differ from the cells cultivated at optimal temperature by the amount of some amino acids and oligopeptides liberated by the yeast into the cultural broth, by the chemical composition of the cells and their morphology.

Intact vacuoles were isolated from the homogenate of the Candida tropicalis protoplasts by flotation in a stepwise gradient of phycoll density. New parameters of protoplast decomposition in hypotonic and isotonic conditions yielding intact vacuoles have been found, as well parameters of density gradient and conditions of centrifugation which differ essentially from parameters used by other authors for isolating the vacuoles from the Saccharomyces cells. The purity of the vacuole preparations was confirmed by using enzymes, light and electron microscopy. The specific content of the carbon of protein, lipids, and free amino acids in the vacuoles and protoplasts of the yeast cells cultivated on 14C-labelled glucose was determined by the radioindicator technique.

Properties of a dark-brown pigment complex isolated from the spores, mycelium and cultural broth of Actinomyces umbriferus by a conventional technique were compared. The complex consists of three fractions: one is a true melanin while two other fractions differ by several characteristics from melanins and from each other. The fraction which is most similar to melanin prevails in the spores, is contained, in a relatively small amount, in the mycelium, and is absent from the cultural broth. Melanin isolated from the spores has a low relative content of carbon and nitrogen and a higher ash content as compared to melanin isolated from the vegetative mycelium. The pigment complex of the spores is characterized also by differences in properties of the first isolated fraction. The pigment complex from the cultural broth differs from the complex of the mycelium and spores by properties of the studied fractions.

The ingredients and chemical content of 135 biliary calculi from 120 operated patients was studied roentgenostructurally, with infra-red spectrophotometry and visually. Based on the results obtained, it proved feasible to differentiate 4 groups of calculi differing in their content: cholesterol, metallocholesterol, cholesterolphosphatide, phosphatide-protein.

A colorimetric method for the rapid determination of the quantitative content of microbial mass in B. pertussis suspensions has been developed. The method is based on the indirect determination of carbon in microbial suspensions by its oxidation with the mixture consisting of potassium bichromate in concentrated sulfuric acid and the subsequent colorimetric analysis of the products of this reaction. The method ensures sufficient accuracy, the determination procedure is simple, takes not more than 2 hours and requires no complex reagents. The results thus obtained are well comparable with those obtained by the classical gravimetric method. The new method permits the determination of microbial mass in B. pertussis suspensions with a minimum concentration of 0.5 mg/ml. The method is recommended for the determination of dry microbial mass in B. pertussis suspensions.

The coating of titanium nitride increases the working life a microsurgical instruments by 1.5 times. The coating is resistant to the bactericidal treatment.

Carcinogenicity of the extract of "unorganized" emission of coke-oven batteries of the coke and by-product processes, 15 polycyclic hydrocarbons (PAH), solution of 4 carcinogenic PAH and benz(a)pyrene (BP) was studied in longterm experiments on (CBAXC57Bl/6)F1 hybrid mice. 1.5 ml of olive oil containing 1 mg of BP or the respective amount of PAH proportionally to their content in the extract were administered to each mouse. The sarcomas developed in 46.6% of mice which had received injections of the extract and in 95 to 100% of mice which had received injection of PAH and BP solution. Thus, the results demonstrated that besides carcinogenic PAH the emissions contain substances which inhibit the tumour development. Our data confirm a possibility of using BP as an indicator in the evaluation of carcinogenicity of industrial emission discharges of the coke and by-product processes.

The paper discusses possible application of the method of measuring the total content of organic carbon to evaluate the quality or reclaimed water. The paper gives data on the content of organic carbon, ratio of chemical consumption of oxygen and carbon in the atmospheric condensate, urine, condensate of urine low-temperature evaporation and portable water reclaimed from these sources.