Researchers in India say they have developed a prototype of an energy-harvesting device from the cocoons of a domesticated species of silk moth. They hope to put the technology to practical use while also tackling waste materials from the silk processing industry.
The researchers found that the cocoon membranes of the mulberry silk moth Bombyx mori contain trace amounts of several elements such as sodium, chlorine, potassium, magnesium, sulphur, calcium and copper; as well as carbon, nitrogen and oxygen.
Wetting the cocoon makes the elements form mobile charge-carrying ions, producing an electric current across the cocoon membrane. The researchers used this current to light an LED.
They attached an aluminium electrode to the inner surface of a cocoon and a copper electrode to the outer surface, and exposed the cocoon to water vapour. Three such cocoons were connected in series to light an LED.
The Wikimedia Foundation is on the quest to expand its content and access to it for users in developing nations.
As part of its ‘Wikipedia Zero’ initiative the foundation is trying to make mobile access to Wikipedia free of internet data charges and to develop content in local languages.
“We started Wikipedia Zero because we [perceived] the trend that Wikipedia usage is shifting to mobiles, and [for it to] grow and expand in developing countries, we needed to [do more to] support the service on mobile,” says Carolynne Schloeder, director of mobile programs at the Wikimedia Foundation.
The foundation is partnering with mobile phone operators in developing countries to enable free internet access to Wikipedia. When a user accesses Wikipedia through an operator that has agreed to provide free usage, a message would appear to confirm that the page is free. When the user clicks an external link that may carry a cost to visit a warning message would show up.
An online repository of maps has been launched to make information on freshwater biodiversity available on a common platform for use by scientists, policymakers, conservationists and NGOs.
The Global Freshwater Biodiversity Atlas will help developing countries identify biodiversity-rich areas for conservation.
It was launched last month (29 January), as part of an EU-funded project called BioFresh, with the aim of putting together published maps and sharing them under a creative commons licence.
Experts say it could help developing nations better manage their biodiversity and meet targets, for example by identifying the areas where conservation can be most effective.
Vanessa Bremerich, the technical editor of the atlas who is based at the Leibniz Institute of Freshwater Ecology and Inland Fisheries, in Germany, says that in contrast to maps published in scientific papers — which are scattered across different journals and are often hard to access — the atlas will be an “an open platform that presents all the research results and data in one place”.
A Wikipedia-style site that gets people to upload information on sustainable technologies and has received more than 50 million page views since its launch in 2006 is going through a raft of changes aimed at improving it further.
The site, called Appropedia, is built on open-source wiki software and allows information to be shared on technologies that could help improve lives in the developing world.
“We focus on sustainable technologies and how to use them in resource-poor settings,” says Lonny Grafman, founder and president of Appropedia.
As is the case with Wikipedia, anyone can edit Appropedia pages that currently hold close to 6,000 articles on topics including agriculture, energy, water and transport.
Appropedia has also collaborated with the WHO to host a catalogue of medical devices for use in poor countries. The Global Health Medical Device Compendium was developed by students at the University of Michigan, United States
Reintroducing prawns to lakes and rivers in which they have been partially or fully lost may be a sustainable way of controlling the parasitic disease schistosomiasis, which kills more than 200,000 people every year in Sub-Saharan Africa alone, says a study.
Researchers have found some native prawns to be voracious predators of the freshwater snails that transmit schistosomiasis parasites and so could be used as a biological control, they report in a study in press in Acta Tropica.
Field tests are under way in Senegal, and researchers suggest that farming the edible prawns could help local populations cut disease while also providing an additional source of income.
“Prawns may offer a simple and affordable transmission control solution in rural poor communities where few alternatives exist and drug treatment is failing to achieve long-term disease reductions,” the study says.
People get infected from contact with water containing schistosomiasis parasites, which are released by infected snails.