Global distribution and diversity of marine Verrucomicrobia

Author Posting. © The Author(s), 2011. This is the author's version of the work. It is posted here by permission of Nature Publishing Group for personal use, not for redistribution. The definitive version was published in The ISME Journal 6 (2012): 1499-1505, doi:10.1038/ismej.2012.3.Verrucomicrobia is a bacterial phylum that is commonly detected in soil but little is known about the distribution and diversity of this phylum in the marine environment. To address this, we analyzed the marine microbial community composition in 506 samples from the International Census of Marine Microbes as well as eleven coastal samples taken from the California Current. These samples from both the water column and sediments covered a wide range of environmental conditions. Verrucomicrobia were present in 98% of the analyzed samples and thus appeared nearly ubiquitous in the ocean. Based on the occurrence of amplified 16S rRNA sequences, Verrucomicrobia constituted on average 2% of the water column and 1.4% of the sediment bacterial communities. The diversity of Verrucomicrobia displayed a biogeography at multiple taxonomic levels and thus, specific lineages appeared to have clear habitat preference. We found that Subdivision 1 and 4 generally dominated marine bacterial communities, whereas Subdivision 2 was confined to low salinity waters. Within the subdivisions, Verrucomicrobia community composition were significantly different in the water column compared to sediment as well as within the water column along gradients of salinity, temperature, nitrate, depth, and overall water column depth. Although we still know little about the ecophysiology of Verrucomicrobia lineages, the ubiquity of this phylum suggests that it may be important for the biogeochemical cycle of carbon in the ocean.We would like to thank the UCI Undergraduate Research Opportunity Program (S.F.), the National Science Foundation (OCE-0928544 and OCE-1046297, A.C.M.) and the Alfred P. Sloan Foundation (S.H., D.M.W., M.S.) for supporting the work

Arbeitsmarkt und Demographie

Im vorliegenden Beitrag werden die wechselseitigen Beziehungen von demographischen Veränderungen und Arbeitsmarktentwicklungen anhand eines Literaturüberblicks diskutiert. Insbesondere werden die Effekte von demographischen Strukturen und Prozessen auf die Lohnstruktur und auf die Arbeitslosigkeit präsentiert, wobei sowohl Mikro- als auch Makroansätze diskutiert und die Implikationen der Bevölkerungsalterung für den Arbeitsmarkt besprochen werden. In Mikroansätzen werden z.B. altersspezifische Profile der Humankapitalbildung als optimale Lösung eines individuellen Entscheidungsproblems modelliert. Im Gegensatz dazu werden in Makroansätzen die Beziehung von Makrovariablen, z.B. Jugendarbeitslosigkeit und Besetzungsstärke der eigenen Kohorte, modelliert. Schließlich stellen wir verschiedene theoretische Perspektiven vor, welche Effekte arbeitsmarktrelevanter Faktoren auf die Fertilität untersuchen

New Media Ecology and Theoretical Foundations for Nonfiction Digital Narrative Creative Practice

Digital storytelling techniques and persuasive communications are becoming increasingly intertwined and realized in cultural discourses such as cultural heritage, environmental activism, and politics. Rhetorical theory has grounded and influenced communication practice since the age of oration, and as society is increasingly undergoing new mediatization, digital rhetorical theory can be reexamined and applied to nonfiction digital narratives for improved practice. Narratology provides key theoretical foundations that are braided into digital rhetoric for application to digital nonfiction narratives. This article highlights how new media has changed the impacts of the modes of persuasion (ethos, pathos, logos, and kairos) on today's multimedia-consuming audiences and how the classical rhetorical canons (invention, arrangement, style, delivery, and memory) can be reframed and updated by incorporating narrative theory to aid creators of new nonfiction digital narratives across different genres

Intact polar lipids of anaerobic methanotrophic archaea and associated bacteria.

Previous biomarker studies of microbes involved in anaerobic oxidation of methane (AOM) have targeted non-polar lipids. We have extended the biomarker approach to include intact polar lipids (IPLs) and show here that the major community types involved in AOM at marine methane seeps can be clearly distinguished by these compounds. The lipid profile of methanotrophic communities with dominant ANME-1 archaea mainly comprises diglycosidic GDGT derivatives. IPL distributions of microbial communities dominated by ANME-2 or ANME-3 are consistent with their phylogenetic affiliation with the euryarchaeal order Methanosarcinales, i.e., the lipids are dominated by phosphate-based polar derivatives of archaeol and hydroxyarchaeol. IPLs of associated bacteria strongly differed among the three community types analyzed here; these differences testify to the diversity of bacteria in AOM environments. Generally, the bacterial members of methanotrophic communities are dominated by phosphatidylethanolamine and phosphatidyl-(N,N)-dimethylethanolamine species; polar dialkylglycerolethers are dominant in the ANME-1 community while in ANME-2 and ANME-3 communities mixed acyl/ether glycerol derivatives are most abundant. The relative concentration of bacterial lipids associated with ANME-1 dominated communities appears significantly lower than in ANME-2 and ANME-3 dominated communities. Our results demonstrate that IPL analysis provides valuable molecular fingerprints of biomass composition in natural microbial communities and enables taxonomic differentiation at the rank of families to orders