Photosynthetic diatoms and marine bacteria contribute about one third of the net primary production in marine environments. Understanding the interactions between these two organisms is potentially important to the over all flow of carbon in the marine ecosystem.
Peroxiredoxins (Prxs) are a ubiquitous family of cysteine-dependent peroxidase enzymes that play dominant roles in regulating peroxide levels within cells. These enzymes, often present at high levels and capable of rapidly clearing peroxides, display a remarkable array of variations in their oligomeric states and susceptibility to regulation by hyperoxidative inactivation...
The ¹⁴C-uptake method is the most common approach employed for estimating primary production in the ocean. Normalizing ¹⁴C-uptake to chlorophyll a and time yields a value termed the assimilation number, which is thought to reflect phytoplankton physiology. It is often assumed that the measured rate of ¹⁴C-uptake is between net...
Exotic species dominate many communities; however the functional significance of species’ biogeographic origin remains highly contentious. This debate is fuelled in part by the lack of globally replicated, systematic data assessing the relationship between species provenance, function and response to perturbations. We examined the abundance of native and exotic plant...
Rapid Arctic warming is associated with important water cycle changes: sea ice loss, increasing atmospheric humidity, permafrost thaw, and water-induced ecosystem changes. Understanding these complex modern processes is critical to interpreting past hydrologic changes preserved in paleoclimate records and predicting future Arctic changes. Cyclones are a prevalent Arctic feature and...
The recent multistate outbreak of
a multidrug-resistant (MDR) Salmonella Heidelberg
strain from commercial poultry production highlights
the need to better understand the reservoirs of these
zoonotic pathogens within the commercial poultry production
and processing environment. As part of a larger
study looking at temporal changes in microbial communities
within the...
We measured activity levels of cesium radioisotopes ¹³⁴Cs and ¹³⁷Cs in wild edible fungi, mineral soil, and surface litter of the west coast of North America from southern California to northern Vancouver Island after the Fukushima nuclear accident. All activity measurements were below governmental limits for human health. ¹³⁷Cs activity...
Consuming cruciferous vegetables such as broccoli sprouts, kale, Brussels sprouts, and bok choy is associated with several health benefits, such as a decreased risk of certain cancers. Cruciferous vegetables contain the glucosinolate, glucoraphanin (GFN). Cutting, chopping or chewing these vegetables releases the enzyme myrosinase, which transforms GFN into sulforaphane (SFN)....
Human alterations to nutrient cycles[superscript 1,2] and herbivore communities³⁻⁷
are affecting global biodiversity dramatically². Ecological theory predicts
these changes should be strongly counteractive: nutrient addition
drives plant species loss through intensified competition for
light, whereas herbivores prevent competitive exclusion by increasing
ground-level light, particularly in productive systems[superscript 8,9]. Here we...
Studies of experimental grassland communities¹⁻⁷ have demonstrated
that plant diversity can stabilize productivity through species
asynchrony, in which decreases in the biomass of some species
are compensated for by increases in others[superscript 1,2]. However, it remains
unknown whether these findings are relevant to natural ecosystems,
especially those for which species...