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‘World’s Most Useful Tree’ Provides Low-Cost Water Purification Method for Developing World
Posted by wideant in Cell & Microbiology on March 20, 2010
A low-cost water purification technique published in Current Protocols in Microbiology could help drastically reduce the incidence of waterborne disease in the developing world. The procedure, which uses seeds from the Moringa oleifera tree, can produce a 90.00% to 99.99% bacterial reduction in previously untreated water, and has been made free to download as part of access programs under John Wiley & Sons’ Corporate Citizenship Initiative.
A billion people across Asia, Africa, and Latin America are estimated to rely on untreated surface water sources for their daily water needs. Of these, some two million are thought to die from diseases caught from contaminated water every year, with the majority of these deaths occurring among children under five years of age. Michael Lea, a Current Protocols author, and a researcher at Clearinghouse, a Canadian organisation dedicated to investigating and implementing low-cost water purification technologies, believes the Moringa oleifera tree could go a long way to providing a solution.
“Moringa oleifera is a vegetable tree which is grown in Africa, Central and South America, the Indian subcontinent, and South East Asia. It could be considered to be one of the world’s most useful trees,” said Lea. “Not only is it drought resistant, it also yields cooking and lighting oil, soil fertilizer, as well as highly nutritious food in the form of its pods, leaves, seeds and flowers. Perhaps most importantly, its seeds can be used to purify drinking water at virtually no cost.” Read the rest of this entry »
A cell’s ‘cap’ of bundled fibers could yield clues to disease
Posted by wideant in Biotechnology on March 12, 2010
Researchers from the Johns Hopkins Engineering in Oncology Center have shown that in healthy cells, a bundled “cap” of thread-like fibers holds the cell’s nucleus, its genetic storehouse, in its proper place. Understanding this cap’s influence on cell and nuclear shape, the researchers say, could provide clues to the diagnosis and treatment of diseases such as cancer, muscular dystrophy and the age-accelerating condition known as progeria.
“Under a microscope, the nucleus of a sick cell appears to bulge toward the top, while the nucleus of a healthy cell appears as a flattened disk that clings to the base,” said principal investigator Denis Wirtz, professor of chemical and biomolecular engineering and director of the Engineering in Oncology Center. “If we can figure out how and why this shape-changing occurs, we may learn how to detect, treat or perhaps even prevent some serious medical disorders.” Read the rest of this entry »
Blue whales singing with deeper voices
Posted by wideant in Plants & Animals on March 5, 2010
Blue whales, the largest animals on earth, are singing with deeper voices every year, but scientists are unsure of the reason.
Whale Acoustics is a company that specializes in recording the songs of blue whales off the coast of California. According to their President, Mark McDonald, they have many recordings of blue whales, but each year they have had to recalibrate their song detectors to lower frequencies. Possible reasons include noise pollution at sea, new mating strategies, and changing population dynamics, but none of these theories is convincing.
McDonald, along with John Hildebrand and Sarah Melnick of the Scripps Institution of Oceanography, have collected and analyzed thousands of recordings of blue whales from the 1960s onwards, from populations around the globe, and have found the tonal frequency of the songs has reduced by fractions of a Hertz every year. Read the rest of this entry »