Estimates of denitrification based on standard methods often cannot easily be extrapolated to entire ecosystems because of high spatial heterogeneity in rates of denitrification. Diel changes in the concentration of dinitrogen (N2) in running waters provide the basis for estimating denitrification by an open-channel technique in much the same way that ecosystem metabolism can be estimated from ...

Open channel block is a process in which ions bound to the inside of a channel pore block the flow of ions through that channel. Repulsion of the blocking ions by depolarization is a known mechanism of open channel block removal. For the NMDA channel, this mechanism is necessary for channel activation and is involved in neuronal plasticity. Several types of transient receptor potential (TRP) ch...

Recent studies of the bacterial mechanosensitive channel MscL have combined a number of different approaches to come up with a model for the channel gating mechanism.

The spitting cobra Naja pallida can eject its venom towards an offender from a distance of up to two meters. The aim of this study was to understand the mechanisms responsible for the relatively large distance covered by the venom jet although the venom channel is only of micro-scale. Therefore, we analysed factors that influence secondary flow and pressure drop in the venom channel, which incl...

In an experimental study of laser sheet bending, a 160W diode laser is used for twodimensional sheet bending of low-carbon steel. The variables investigated include metal sheet thickness, laser scan speed, laser power, laser beam width, and laser scan pass number. Bend surface appearances are also analysed. The laser sheet bend results demonstrate that a 940Nm diode laser is an effective tool f...

ntercalation—the slotting of cells in between one another—is an established method for converting short and fat into long and slim. This is all very well in slippery, adhesion-sparse mesenchymal tissues. But many such extension events occur in epithelial tissues, where cells are glued together by adhesion complexes. Claire Bertet, Lawrence Sulak, and Thomas Lecuit (IBDM, Marseille, France) now ...

The modeling of flood-induced bend scour near embankment toes can provide important information for river engineering, embankment safety warnings, and emergency action management. During the rainy seasons, short-term general scour and bend scour are the most common causes for the failure of reinforced concrete embankments in Taiwan. To gain a deeper understanding of the scouring process near le...