Shocking as it may seem, wastewater flushed down toilets and sinks is getting a new life thanks to special fuel cells that use it to produce electricity, according to the latest video in the American Chemical Societys Bytesize Science series.
In the video, Bruce Logan, of Penn State, points out that sewage treatment traditionally has been a big consumer of electricity. With the new fuel cells, that situation could be reversed, with sewage becoming the raw material for making electricity, Logan says. In the video, he explains how bacteria in the fuel cells feed on organic matter in wastewater to produce electrons the stuff of electricity.
www.BytesizeScience.com. American Chemical Society
Robot-test results: Drunken fish are less fearful
The latest experiments testing the ability of robots to influence live animals shows that bio-inspired robots can elicit fear in zebrafish but that this reaction can be modulated by alcohol.
Maurizio Porfiri, a professor of mechanical and aerospace engineering at the Polytechnic Institute of New York University, and Simone Macrì, of the Istituto Superiore di Sanità, in Rome, published their findings in PLOS ONE.
Previous studies established that zebrafish show a strong affinity for robots designed to swim and appear as one of their own and that this preference can be abolished by exposing the fish to ethanol. This time, the scientists designed a robot mimicking the Indian leaf fish a natural predator of the zebrafish. In the lab, they placed a zebrafish and the robotic Indian leaf fish in separate compartments of a three-section tank. The control group uniformly avoided the robotic predator, showing a preference for the empty section.
To determine whether alcohol would affect fear responses, the researchers exposed separate groups of fish in water to different doses of ethanol which has been shown to influence anxiety-related responses in humans, rodents and some species of fish. The zebrafish exposed to the highest concentrations of ethanol showed remarkable changes in behavior, failing to avoid the predatory robot. poly.edu
Ancient Halls of the dead unearthed in Britain
The remains of two large 6,000-year-old halls, each buried within a prehistoric burial mound, have been found within a hill in Herefordshire, England. The buildings, probably used by entire communities, are of unknown size, but may have been of similar length to the Neolithic long barrows beneath which they were found: 98 and 230 feet.
They were, according to the archeologists who found them, deliberately burnt down after they were constructed and their remains incorporated into the two burial mounds. But much detail has been preserved in the larger barrow: structural timbers in carbonized form, postholes showing the positions of uprights, and the burnt remains of stakes forming internal partitions.
The buildings were likely to have been long structures with aisles, framed by upright posts, and with internal partitions.
The smaller barrow contains a 23-foot-by-8-foot mortuary chamber, with huge sockets that would have held upright tree trunks at each end.
Julian Thomas, an archaeologist from the University of Manchester, and Keith Ray, the Herefordshire Councils county archaeologist, co-directed the excavation. manchester.ac.uk