Microbial transformations of toxic monomethylmercury(MMHg) and dissolved gaseous mercury(DGM) at the lower levels of the marine food web are not well understood, especially in oligotrophic and phosphorus-limited seas....
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Microbial transformations of toxic monomethylmercury(MMHg) and dissolved gaseous mercury(DGM) at the lower levels of the marine food web are not well understood, especially in oligotrophic and phosphorus-limited seas. To examine the effects of probable phosphorus limitation(~PP-limitation) on relations between mercury(Hg) fractions and microorganisms, we determined the total mercury(THg), total methylated mercury(MeHg), DGM, and microbiological and chemical parameters in the Central Adriatic Sea. Using statistical analysis, we assessed the potential microbial effects on Hg transformations and bioaccumulation. Only in the absence of ~PP-limitation conditions(^(NO–P)P-limitation) is MeHg significantly related to most chemical and microbial parameters, indicating metabolism-dependent Hg transformations.The heterotrophic activity of low nucleic acid bacteria(abundant in oligotrophic regions)seems responsible for most of Hg methylation under ^(NO–P)P-limitation. Under these conditions,DGM is strongly related to microbial fractions and chlorophyll a, indicating biological DGM production, which is probably not metabolically induced, as most of these relations are also observed underPP-limitation. MMHg biomagnification was observed through an increased bioaccumulation factor from microseston to mesozooplankton. Our results indicate that Hgtransformations and uptake might be enhanced under ^(NO–P)P-limitation conditions, emphasizing their impact on the transfer of Hg to higher trophic levels.
This paper displays the results of a survey of public music performances held during 2010 in Skopje, the capital of the Republic of Macedonia. Study of the audience of public musical events was limited only to the num...
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This paper displays the results of a survey of public music performances held during 2010 in Skopje, the capital of the Republic of Macedonia. Study of the audience of public musical events was limited only to the number of visitors. Field research included 653 musical events with a total of 545,340 visitors grouped into eight categories according to the preference by genres of music preference, age, status symbol, origin of the performers, space, and organizers. Our experience in monitoring public musical events through personal presence, the recorded materials, and the continuous monitoring of information from electronic and print media, enabled us to record events and to build some initial comments and assumptions about the structure of the audience and music preference. We have chosen to consider the impact of the sociological determinants on the preference of the audience in the public musical performances through the music genres, the age, the status symbol, the origin of the performers, the area of maintenance, and the organizers of musical events. According to the genre distribution, classical music events prevail, and the greatest numbers of visitors are registered at the pop rock concerts. The structure of the audience according to the age varies depending on the musical genre, so the widest age structure covers the events of pop rock music.
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