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Sont décrits les microfossiles des sédiments marins du Jurassique supérieur, extraits du sondage à Magnuszew et appartenant aux groupes suivants: les Dinoflagellés, les Acritarches, les microfossiles incertae sedis et les Algues sédentaires. Les Dinoflagellés appartiennent à 12 espèces, parmi lesquelles ont été distingués 2 nouveaux genres: Tetrasphaera n.gen, et Palaeosphaerium n.gen., ainsi que 5 nouvelles espèces: Palaeoperidinium nuciformoides n.sp., P. rhomboidalis n.sp., Hystrichosphaeridium polonicum n.sp., Tetrasphaera rara n.sp. et Palaeosphaerium infrequens n.sp. Parmi les Acritarches on a distingué 4 espèces, et parmi les microfossiles incertae sedis - 3 espèces attribuées aux deux genres nouveaux; ce sont: Dictyochroa ovalis n.gen., n.sp., Alisum magnum n.gen., n.sp. et Alisum parvum n.sp. Sont décrits, en outre: un microfossile problématique, génériquement et spécifiquement indéterminable, ainsi que deux menues Algues, appartenant, probablement, aux Chlorophycées. Une liste de la répartition stratigraphique des microfossiles, se trouvant dans les échantillons examinés, est jointe au travail.
We present the results of investigations of microorganisms present in aerosol emitted by selected devices of two mechanical-biological wastewater treatment plants (“Debogorze” and “Gdańsk-Wschód”). In 2002, 5 series of measurements were conducted at each of the plants. The samples of air were collected by means of sedimentation method (PN-89/Z-04008/08) and by means of filtration method, using an air sampler produced by Merck. Apart from measurements of microbiological analyses, consisting of determinations of the total number of psychrophillic and mezophillic bacteria, manitol-positive and manitol-negative staphylococcus, hemolysing staphylococcus, Pseudomonas fluorescens, coliform bacteria and the number of spores of phycomycetes, weather conditions were also monitored. The most numerous microorganisms in the monitored air were psychrophillic bacteria and spores of phycomycetes. The number of psychrophillic bacteria varied in the wide range from 14 to 5255 CFU/m3, the number of mezophillic bacteria changed from 1 to 1324 CFU/m3, the number of staphylococcus – from 1 to 150 CFU/m3, the numbers of Pseudomonas fluorescens and the coliforms varied from a few to 50 CFU/m3 and the spores of phycomycetes varied from a few to 5,250 CFU/m3 of air (collected by means of Merck air sampler). It was found out that in both plants the main sources of microorganisms were sludge recirculation chambers and sand traps. The air around aeration chambers of activated sludge contained similar numbers of microorganisms as the background. It was proved that the sampling method is of critical effect on measurement results. The number of microorganisms detected in the samples collected by means of sedimentation method was by one order of magnitude higher than in the samples collected by means of filtration method (using air sampler), allowing for strict control of the filtered air volume.
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The article reviews the issue of antibiotic resistance of microorganisms to meropenem in intensive care units in Ukraine. An increase in meropenem inefficiency against microorganisms in intensive care units has been observed in the last years. The data analysis suggests a significant predominance of gram-negative flora: A. baumannii, Р. aeruginosa, К. pneumoniae, E. cloacae, E.coli. On average 30% of microorganisms are resistant to 5 and more basic antibiotics including meropenem. 40-80 % of the gram-negative flora in intensive care units in Ukraine are resistant to meropenem. This can be attributed to the free sale of antibiotics without prescription, patients’ self-treatment, inadequate antibiotic therapy, and failure to comply with sanitary norms on the part of intensive care staff. Microbiological diagnostics of infectious pathogens also needs improvement. Unless proper measures are taken within a few years, meropenem as an antibiotic is likely to disappear in Ukraine.
Coir pith is being considered as the reject generated during the extraction of coir fibre from coconut husks. It is a light weight and fluffy material with dusts and bits of fibres. The coir pith has many undesirable components and hence it does not carry any value addition. It needs to be degraded for the effective utilization for further activities. Microbes have the ability to decompose coir pith. Coir pith itself posses its own native microbes. Hence in the present study, raw coir pith and the soil dumped with coir pith in the dumping yards along the vicinity of the coir fibre factories were subjected for the enumeration and characterization of microorganisms. The coir pith for the study was collected from two locations in Cuddalore District. The results exhibited the presence of huge quantity of microbes in the raw coir pith than the coir pith dumped soil. Furthermore, the percentage occurrence of bacteria was significantly higher when compared with that of the fungi and actinomycetes. Totally 12 species of bacteria, six species of fungi and three species of actinomycetes were recorded. The results showed significant variation in the quantity and quality of the microbes.
This work concerns the influence of temperature, the presence (lack of oxygen and different carbohydrates) on solubilization of tribasic calcium phosphate, iron phosphate and Thomas basic slag in samples of bottom sediments of gyttja, sapropel, "dy" and tyrfopel types from lakes of different trophic lakes of the Mazurian Lake District. In samples of 4 types of bottom sediments more PO4-P from phosphate compounds gathered at 25° C than at lower temperatures in situ in lakes; besides, there were more in anaerobic conditions than in aerobic ones, in bottom sediments samples with Ca3(P04)2 more PO4-P gathered at pH 4-5, in samples with FeP04 at pH 5-6, in samples with Thomas basic slag at pH 4-6. More PO4-P was in samples of bottom sediments with addition of glucose, saccharose, mannose and arabinose, less with the addition of xylose and cellobiose independently from used phosphate compounds. Greater amounts of PO4-P gathered in the samples of bottom sediments of gyttja and sapropel types, lower in the samples of "dy" and tyrfopel types. In all series of the experiments the highest amounts of P04-P gathered in a logarythmic phase of the development of natural population of bacteria.
The aim of our experiment was to determine the effect of heating oil application on the count of microorganisms and some physico-chemical properties of limed and lime-free soil and soil sown with yellow lupine of the Markiz variety and unsown soil. The results obtained indicate that heating oil deteriorated the physico-chemical properties of the experimental soil (acidification, decrease in the total alkaline exchangeable cations, soil exchange capacity and alkaline cation soil saturation). At the same time, it stimulated, to a different degree, the multiplication of soil microorganisms, especially oligotrophic bacteria (10-fold) and bacteria representing the genera of Pseudomonas spp. (8-fold). Lime application and cultivation of yellow lupine had a positive effect on the physico-chemical properties of soil and stimulated the growth of Azotobacter spp.
An effective microorganism for phenol degradation process was selected and isolated from the natural environment using basic screening. The tested strain Alcaligenes xylosoxidans ssp. denitrificans was compared in vital activity experiments to the CCM strain Pseudomonas putida 3423 in order to obtain optimal biochemical parameters and to find out the right way of cultivation for the preparation of an inoculum. The efficiency of phenol degradation at higher concentrations is strongly influenced by microorganism age and, of course, by the initial substrate concentration. The time of biodegradation with the increase of initial phenol concentration was increased, but to the critical concentration was independent of it. The method of preparation of an inoculum with highly induced oxygenase system was found. A suitable composition of the broth medium for precultivation and cultivation of tested microorganisms has resulted from this work.
An attempt was made to characterise thermophilic microflora isolated in an industrial plant utilising food industry waste. Initial estimation of environmental requirements of a mixed microorganism population was performed using the method measuring changes in electrical im­pedance by means of the BacTrac 4100 Automatic Microorganisms Growth Analyzer. Control of the dynamics of microorganism growth on broth media supple­mented with sources of carbon, nitrogen and phosphorus and at various pH allowed initial assessment of their en­vi­ron­men­tal requirements. The course of alterations in electrical impedance during culturing of both single isolates and mixed mi­cro­or­ganism populations can be described by means of Gompertz’s curve characteristic for bacteria growth with a very high correlation coefficient. The mixed microorganism population and isolates obtained from it were also characterised from the point of view of their biodegradation potentials of wastewater obtained in the potato processing industry. Biodegradation processes carried out in conditions of shake flask cultures at a temperature of 55oC showed higher reducing potentials of chemical oxygen demand (COD) of a mixed bacteria culture. Single isolates were characterised by a distinctly inferior metabolic activity and lower biodegradation potentials of “ hot” potato wastewater.
The studies focused on the effect of the addition of low concentrations of glucose - a substrate that is readily subject to microbiological degradation, on the rate of biodégradation of petroleum products. Glucose in concentration 1% was introduced into mineral medium containing 3% crude oil, with or without bacterial inoculum. The rate of degradation of crude oil in the individual cultures was determined for 3 weeks. The degradation of petroleum products in liquid mineral medium reached 56% after 21 days of growth in the presence of 1% concentration of glucose. The introduction of bacteria that had been cultured earlier in the presence of petroleum products had an effect on hydrocarbon removal efficiency - in both the presence and absence of glucose, the percent reduction of crude oil was high, reaching 76 and 86, respectively, after 21 days.
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