In the Sonora Margin cold seep ecosystems (Gulf of California), sediments underlying microbial mats harbor high biogenic methane concentrations, fueling various microbial communities, such as abundant lineages of anaerobic methanotrophs (ANME). However, the biodiversity, distribution, and metabolism of the microorganisms producing this methane remain poorly understood. In this study, measuremen...

Ecosystem uptake and transfer processes of Sellafield-derived radiocarbon (14C) within the Irish Sea were examined. Highly variable activities in sediment, seawater and biota indicate complex 14C dispersal and uptake dynamics. All east basin biota exhibited 14C enrichments above ambient background while most west basin biota had 14C activities close to background, although four organisms includ...

The active bacterial community able to utilize benzoate under denitrifying conditions was elucidated in two coastal sediments using stable-isotope probing (SIP) and nosZ gene amplification. The SIP method employed samples from Norfolk Harbor, Virginia, and a Long-Term Ecosystem Observatory (no. 15) off the coast of Tuckerton, New Jersey. The SIP method was modified by use of archaeal carrier DN...

AIMS The objectives of this work were to explore the diversity in Fe (III)-reducing enrichment cultures from the deep subsurface and to identify strains involved in metal reduction. METHODS AND RESULTS Analyses of 16S ribosomal RNA (rRNA) of enrichments, supplemented with hydrogen, acetate or pyruvate as an electron donor, identified three dominant operational taxonomic units (OTUs). All cult...

Izmir Bay is one of the great natural bays of the Mediterranean. The surface sediment and fish samples were collected during 1997-2009. The sediment concentrations of inner bay showed significant enrichments during sampling periods. Outer and middle bays exhibited low levels of metal enrichments except the estuary of Gediz River. The concentrations were generally higher than the background leve...

We use a generic notion of flatness in the enriched context to define various completions of metric spaces – enrichments over [0, ∞] – and preorders – enrichments over 2. We characterize the weights of colimits commuting in [0, ∞] with the conical terminal object and cotensors. These weights can be interpreted in metric terms as peculiar filters, the so-called filters of type 1. This generalize...

Using recently measured rates for isotopic variants of the ozone formation reaction , we derive expressions for the enrichment of symmetric and asymmetric and in stratospheric ozone and calculate total enrichments of 123‰ and 107‰ for and , respectively. We compare the calculations with measurements made with the Smithsonian Astrophysical Observatory far-infrared spectrometer during seven ballo...

A series of molecular and geochemical studies were performed to study microbial, coal bed methane formation in the eastern Illinois Basin. Results suggest that organic matter is biodegraded to simple molecules, such as H(2) and CO(2), which fuel methanogenesis and the generation of large coal bed methane reserves. Small-subunit rRNA analysis of both the in situ microbial community and highly pu...

We define the notion of an additive model category and prove that any stable, additive, combinatorial model category M has a model enrichment over Sp(sAb) (symmetric spectra based on simplicial abelian groups). So to any object X ∈ M one can attach an endomorphism ring object, denoted hEndad(X), in this category of spectra. One can also obtain an associated differential graded algebra carrying ...

The biological interpretation of large-scale gene expression data is one of the challenges in current bioinformatics. The state-of-theart approach is to perform clustering and then compute a functional characterization via enrichments by Gene Ontology terms [1]. To better assist the interpretation of results, it may be useful to establish connections among different clusters. This machine learn...