A global perspective on marine photosynthetic picoeukaryote community structure

A central goal in ecology is to understand the factors affecting the temporal dynamics and spatial distribution of microorganisms and the underlying processes causing differences in community structure and composition. However, little is known in this respect for photosynthetic picoeukaryotes (PPEs), algae that are now recognised as major players in marine CO2 fixation. Here, we analysed dot blot hybridisation and cloning–sequencing data, using the plastid-encoded 16S rRNA gene, from seven research cruises that encompassed all four ocean biomes. We provide insights into global abundance, α- and β-diversity distribution and the environmental factors shaping PPE community structure and composition. At the class level, the most commonly encountered PPEs were Prymnesiophyceae and Chrysophyceae. These taxa displayed complementary distribution patterns, with peak abundances of Prymnesiophyceae and Chrysophyceae in waters of high (25:1) or low (12:1) nitrogen:phosphorus (N:P) ratio, respectively. Significant differences in phylogenetic composition of PPEs were demonstrated for higher taxonomic levels between ocean basins, using Unifrac analyses of clone library sequence data. Differences in composition were generally greater between basins (interbasins) than within a basin (intrabasin). These differences were primarily linked to taxonomic variation in the composition of Prymnesiophyceae and Prasinophyceae whereas Chrysophyceae were phylogenetically similar in all libraries. These data provide better knowledge of PPE community structure across the world ocean and are crucial in assessing their evolution and contribution to CO2 fixation, especially in the context of global climate change

Antimicrobial stewardship, therapeutic drug monitoring and infection management in the ICU: results from the international A- TEAMICU survey.

BackgroundSevere infections and multidrug-resistant pathogens are common in critically ill patients. Antimicrobial stewardship (AMS) and therapeutic drug monitoring (TDM) are contemporary tools to optimize the use of antimicrobials. The A-TEAMICU survey was initiated to gain contemporary insights into dissemination and structure of AMS programs and TDM practices in intensive care units.MethodsThis study involved online survey of members of ESICM and six national professional intensive care societies.ResultsData of 812 respondents from mostly European high- and middle-income countries were available for analysis. 63% had AMS rounds available in their ICU, where 78% performed rounds weekly or more often. While 82% had local guidelines for treatment of infections, only 70% had cumulative antimicrobial susceptibility reports and 56% monitored the quantity of antimicrobials administered. A restriction of antimicrobials was reported by 62%. TDM of antimicrobial agents was used in 61% of ICUs, mostly glycopeptides (89%), aminoglycosides (77%), carbapenems (32%), penicillins (30%), azole antifungals (27%), cephalosporins (17%), and linezolid (16%). 76% of respondents used prolonged/continuous infusion of antimicrobials. The availability of an AMS had a significant association with the use of TDM.ConclusionsMany respondents of the survey have AMS in their ICUs. TDM of antimicrobials and optimized administration of antibiotics are broadly used among respondents. The availability of antimicrobial susceptibility reports and a surveillance of antimicrobial use should be actively sought by intensivists where unavailable. Results of this survey may inform further research and educational activities

Economic photoprotection in photosystem II that retains a complete light-harvesting system with slow energy traps

This work was supported by the Leverhulme Trust grant, RPG-2012-478 and the Royal Society International Joint Project grant 2009/R4 to A.V.R. L.V. and J.C. acknowledge support by the European Social Fund under the Global grant measure

Tuber formation and development of Dioscorea cayenensis-D. rotundata complex in vitro. Effect of polyamines.

Tuberisation was obtained in vitro on yam (Dioscorea cayenensis-D.rotundata complex). The effect of exogenous polyamines on tuber formation and development (length and weight of microtubers) were investigated and discussed in relation with changes in endogenous polyamines. Application of exogenous polyamines, inhibitors of their metabolism and polyamines precursors in various concentrations positively affected microtuber formation by yam nodal cuttings and their further development. In control conditions, three weeks are needed to obtain 100% of tuberisation. With low concentrations of putrescine (10 5 or 10 6 M), tuber formation occurred earlier. Polyamine endogenous level and metabolism can be significantly affected by exogenous polyamines but modifications of endogenous free polyamines could not be directly correlated to the tuber formation process. Increases in endogenous putrescine and auxins were observed in tubers showing a better development in the presence of putrescine. These results can be used for optimising in vitro conditions for mass production of larger microtubers of the Dioscorea cayenensis-D. rotundata complex

Hydroformylation in Aqueous Biphasic Media Assisted by Molecular Receptors

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