Recently developed perfusion micro-bioreactors offer the promise of more physiologic in vitro systems for tissue engineering. Successful application of such bioreactors will require a method to characterize the bioreactor environment required to elicit desired cell function. We present a mathematical model to describe nutrient/growth factor transport and cell growth inside a microchannel biorea...

Research on cycle infrastructure preferences generally suggests a preference for off-road cycle infrastructure and segregation from motor traffic, among both existing cyclists and non-cyclists. However, studies have so far not explored how the presence of children might shape adults’ attitudes to cycle infrastructure. Similarly, studies on the determinants of child cycling have not as yet looke...

There is increasing interest and concern over the impacts of mercury (Hg) inputs to marine ecosystems. One of the challenges in assessing these effects is that the cycling and trophic transfer of Hg are strongly linked to other contaminants and disturbances. In addition to Hg, a major problem facing coastal waters is the impacts of elevated nutrient, particularly nitrogen (N), inputs. Increases...

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Growth factors provide permission signals that allow mammalian cells to grow, proliferate and survive. One mechanism by which growth factors maintain this control is through the regulation of cell surface nutrient transporter expression. Following growth factor withdrawal, nutrient transporters are endocytosed and degraded in the lysosome, effectively terminating the cell's ability to obtain nu...

The use of stored resources to fuel reproduction, growth, and self-maintenance in the face of uncertain nutrient availability is a tactic common to many organisms. The degree to which organisms rely on stored resources in response to varied nutrients, however, is not well quantified. In this study, we used stable isotope methods to quantify the use of stored versus incoming nutrients to fuel gr...

Experiments were performed to determine the effect of community composition on system function (bacterial production) in arctic Alaska. In this system bacterial production is controlled by: community, temperature, nutrients, and carbon source. Lake inlet and outlet communities in these experiments were different in composition, based on PCR-DGGE fingerprinting of 16S rDNA. For both communities,...

Fishing is widely considered a leading cause of biodiversity loss in marine environments, but the potential effect on ecosystem processes, such as nutrient fluxes, is less explored. Here, we test how fishing on Caribbean coral reefs influences biodiversity and ecosystem functions provided by the fish community, that is, fish-mediated nutrient capacity. Specifically, we modelled five processes o...