15 research outputs found

    К проблеме социальной эффективности инноваций в профессиональном образовании

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    Movile Cave, Romania, is an unusual underground ecosystem that has been sealed off from the outside world for several million years and is sustained by non-phototrophic carbon fixation. Methane and sulfur-oxidising bacteria are the main primary producers, supporting a complex food web that includes bacteria, fungi and cave-adapted invertebrates. A range of methylotrophic bacteria in Movile Cave grow on one-carbon compounds including methylated amines, which are produced via decomposition of organic-rich microbial mats. The role of methylated amines as a carbon and nitrogen source for bacteria in Movile Cave was investigated using a combination of cultivation studies and DNA stable isotope probing (DNA-SIP) using 13C-monomethylamine (MMA). Two newly developed primer sets targeting the gene for gamma-glutamylmethylamide synthetase (gmaS), the first enzyme of the recently-discovered indirect MMA-oxidation pathway, were applied in functional gene probing. SIP experiments revealed that the obligate methylotroph Methylotenera mobilis is one of the dominant MMA utilisers in the cave. DNA-SIP experiments also showed that a new facultative methylotroph isolated in this study, Catellibacterium sp. LW-1 is probably one of the most active MMA utilisers in Movile Cave. Methylated amines were also used as a nitrogen source by a wide range of non-methylotrophic bacteria in Movile Cave. PCR-based screening of bacterial isolates suggested that the indirect MMA-oxidation pathway involving GMA and N-methylglutamate is widespread among both methylotrophic and non-methylotrophic MMA utilisers from the cave

    Biogeochemistry of Fe and other trace elements (Al Co Ni) in the upper Atlantic Ocean

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    Iron and other trace metals (Al, Co, Ni) were measured through the upper water column during two north–south transects of the Atlantic Ocean (approximately 50°N–50°S), from the United Kingdom (UK) to the Falkland Islands (September/October 1996) and from South Africa to the UK (May/June 1998). Total dissolvable iron (TD-Fe) concentrations in the surface layers (<200 m) of the open Atlantic Ocean averaged 0.95±0.67 nM (n=142) during the 1996 cruise and 1.08±0.59 nM (n=160) during the 1998 cruise, with increased values in shelf waters at both extremes of the transects. Iron enrichments, fingerprinted via correlation with other trace metals, macronutrients and hydrography, correlated well with dry aerosol deposition off the west African continent and wet deposition in the Inter-Tropical Convergence Zone (ITCZ), with levels >2.2 nM observed in surface waters in these regions. Benthic fluxes provided a significant amount of Fe (2–38 nM) to the base of the water column in coastal zones. In addition, samples collected from one Atlantic Meridional Transect (AMT) expedition were re-analysed after a 16 month acidification period and showed significant increases over shipboard analyses (average values increasing to 2.26±1.50 nM), indicating the extended release of Fe from leachable particulate material in the stored samples. Detailed profiling through the euphotic zone revealed TD-Fe distributions that exhibited strong relationships with biological uptake, regeneration and water column hydrography. In equatorial and tropical North Atlantic waters, trace elemental distributions showed evidence of recent atmospheric deposition through a history of stratified mixed layers

    Developments in anionic polymerization — A critical review

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