Alan Duncan results 32
· Newest (Page 1/2, per page 25)
Author: Alan Duncan ×Clear All Filters
Search Results
Marine phytoplankton form the base of marine food webs and are the driving force of the marine carbon cycle, so understanding the dynamics of their blooms is critical. While near-surface marine productivity (<10 m water depths) is extensively documented, that of the subsurface is less well characterised. Increasing evidence of the importance of subsurface chlorophyll maxima (SCM) and climatically driven increases in stratifica...
Common, low-frequency, rare, and ultra-rare coding variants contribute to COVID-19 severityNARA Subscribed
The combined impact of common and rare exonic variants in COVID-19 host genetics is currently insufficiently understood. Here, common and rare variants from whole-exome sequencing data of about 4000 SARS-CoV-2-positive individuals were used to define an interpretable machine-learning model for predicting COVID-19 severity. First, variants were converted into separate sets of Boolean features, depending on the absence or the pr...
The Croker Carbonate Slabs, in the UK sector of the Irish Sea, has shallow (70 to 100 m) water, strong (> 2 knot) tidal currents, coarse mobile surficial sediments and the most extensive methane-derived authigenic carbonate (MDAC) known in European waters. Multi-disciplinary studies (2004 to 2015) were commissioned specifically to document the benthic habitat, and have resulted in the designation of this site as a Marine Prote...
Summary Ruminococcus bromii is a dominant member of the human colonic microbiota that plays a ‘keystone’ role in degrading dietary resistant starch. Recent evidence from one strain has uncovered a unique cell surface ‘amylosome’ complex that organizes starch‐degrading enzymes. New genome analysis presented here reveals further features of this complex and shows remarkable conservation of amylosome components between human colo...
Wheat bran promotes enrichment within the human colonic microbiota of butyrate‐producing bacteria that release ferulic acidNARA Subscribed
Summary Cereal fibres such as wheat bran are considered to offer human health benefits via their impact on the intestinal microbiota. We show here by 16S rRNA gene‐based community analysis that providing amylase‐pretreated wheat bran as the sole added energy source to human intestinal microbial communities in anaerobic fermentors leads to the selective and progressive enrichment of a small number of bacterial species. In parti...
Trends in daily observed temperature and precipitation extremes over three Ethiopian eco‐environmentsNARA Subscribed
Ethiopia has wide eco‐environmental diversity ranging from extreme heat at one of the lowest places in the world to one of the coolest summits in Africa. Associated with this environmental diversity and climate change, climatic extremes are expected to change over time and also vary across eco‐environments in the country. This study was conducted to examine the trends of past precipitation and temperature extremes over three e...
Forest Management, Engineering, and OperationsNARA Subscribed
9Forests represent a major global C sink, and forest management strategies that maximize carbon storage offer one avenue for mitigating increases in atmospheric carbon dioxide concentrations. Our understanding of relationships between forest management, productivity, carbon storage, and stand age, however, is limited. We established research plots in a chronosequence of thinned and unmanaged red pine stands in northern Minneso...
The species composition of the human intestinal microbiota differs between particle‐associated and liquid phase communitiesNARA Subscribed
Summary Many of the substrates available as energy sources for microorganisms in the human colon, including dietary plant fibre and secreted mucin, are insoluble. It seems likely that such insoluble substrates support a specialized microbiota, and in order to test this hypothesis, faecal samples from four healthy subjects were fractionated into insoluble (washed particulate) and liquid fractions. Analysis of 1252 PCR‐amplified...
Summary Insoluble plant polysaccharides and endogenous mucin are important energy sources for human colonic microorganisms. The object of this study was to determine whether or not specific communities colonize these substrates. Using faecal samples from four individuals as inocula for an anaerobic in vitro continuous flow system, the colonization of wheat bran, high amylose starch and porcine gastric mucin was examined. Recov...