Who Needs the Dark Web? Exploring the Trade in Critically Endangered Plants on eBay.

Stemming the illegal trade of endangered species is a critical and very difficult challenge for conservationists and law enforcement. Much effort is given to stopping the trade of "charismatic megafauna" such as tigers, elephants, and rhinoceroses. Endangered plant species, however, receive far less attention and fewer resources, resulting in devastating consequences.

Bipolar electrode focusing: the effect of current and electric field on concentration enrichment.

Bipolar electrode focusing at discontinuous bipolar electrodes (BPEs) provides new insight into the faradaic current and electric field characteristics associated with the technique and allows for the controlled transport of a focused anionic tracer in a microfluidic channel. The findings corroborate our previously reported simulation results, which describe the formation of an extended electric field gradient leading to concentration enrichment. This gradient has been attributed to the passage of faradaic current through a BPE affixed to the floor of the microchannel.

Bipolar electrode focusing: simultaneous concentration enrichment and separation in a microfluidic channel containing a bipolar electrode.

A method for simultaneously concentrating and separating analytes in a buffer-filled microfluidic channel is reported. The approach is based on modulation of the local electric field within the channel and the corresponding opposition of electrophoretic and electroosmotic flow (EOF) velocities. Dye molecules having different electrophoretic mobilities are focused at different locations within the channel where concentration takes place.

Electric field gradient focusing in microchannels with embedded bipolar electrode.

The complex interplay of electrophoretic, electroosmotic, bulk convective, and diffusive mass/charge transport in a hybrid poly(dimethylsiloxane) (PDMS)/glass microchannel with embedded floating electrode is analyzed. The thin floating electrode attached locally to the wall of the straight microchannel results in a redistribution of local field strength after the application of an external electric field. Together with bulk convection based on cathodic electroosmotic flow, an extended field gradient is formed in the anodic microchannel segment.