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Global update: Plants responsible for global warming?
They have long been thought of as the antidote to harmful greenhouse gases, sufferers of, rather than contributors to, the effects of global warming. But in a startling discovery, scientists have realized that plants are part of the problem.
According to a study published last week, living plants may emit almost a third of the methane entering the Earth’s atmosphere. The result has come as a shock to climate scientists.
“This is a genuinely remarkable result,” said Richard Betts of the climate change monitoring organization the Hadley Centre. “It adds an important new piece of understanding of how plants interact with the climate.”
Methane is second only to carbon dioxide in contributing to the greenhouse effect. “For a given mass of methane, it is a stronger greenhouse gas, but the reason it is of less concern is that there’s less of it in the atmosphere,” said Dr Betts.
But the concentration of methane in the atmosphere has almost tripled in the last 150 years, mainly through human-influenced so-called biogenic sources such as the rise in rice cultivation or numbers of flatulent ruminating animals. According to previous estimates, these sources make up two-thirds of the 600m tonnes worldwide annual methane production.
Frank Keppler, of the Max Planck Institute for Nuclear Physics, who led the team behind the new research, estimated that living plants release between 60m and 240m tonnes of methane per year, based on experiments he carried out, with the largest part coming from tropical areas.
Digging for data
Scientific research is being added to at an alarming rate: the Human Genome Project alone is generating enough documentation to “sink battleships”. So it’s not surprising that academics seeking data to support a new hypothesis are getting swamped with information overload. As data banks build up worldwide, and access gets easier through technology, it has become easier to overlook vital facts and figures that could bring about groundbreaking discoveries.
The government’s response has been to set up the National Centre for Text Mining, the world’s first centre devoted to developing tools that can systematically analyse multiple research papers, abstracts and other documents, and then swiftly determine what they contain.
Text mining uses artificial intelligence techniques to look in texts for entities (a quality or characteristic, such as a date or job title) and concepts (the relationship between two genes, for example). In many ways, it’s more precise and sophisticated than a search engine: it not only tracks down information against specified criteria but can also draw out relationships between hitherto unlinked bits of research.
Initially, the centre is focusing on bioscience and biomedical texts to meet the increasing need for automated ways to interrogate, extract and manage textual information now flooding out of large-scale bio-projects. “Biology is our primary focus as the government has identified that there’s a big problem with all this information that nobody can handle,” says Richard Barker, the centre’s commercial manager.
Hwang blames team
The disgraced scientist Woo-suk Hwang asked fellow South Koreans to forgive him recently for fraudulent claims relating to human stem cell research, but then blamed junior colleagues for the scandal.
“I take full responsibility for the papers and offer you my apology,” Dr Hwang told a news conference. “I ask for your forgiveness. I feel so miserable that it’s difficult even to say sorry.”
But he added that members of the research team at Mizmedi hospital, Seoul, had lied to him about successfully harvesting and growing stem cells from human embryos he had cloned. In 2004 Dr Hwang announced the cloning of the world’s first human embryo, a feat trumped last year by a paper in which he wrote of creating stem cells genetically matched to patients with medical conditions.
Last week he repeated claims that his laboratory had refined the technology, saying he could produce cells within six months.
Seoul National University, where Dr Hwang worked, recently published an investigation which ruled that though he had succeeded in cloning early-stage human embryos, and Snuppy, the Afghan hound, his papers on human stem cells had been entirely fabricated. — Dawn/The Guardian News Service
Vaccines and diarrhea
Two competing vaccines designed to combat rotaviral diarrhoea, one of the world’s leading causes of childhood death, sharply reduced severe disease and hospitalizations, according to the results of two unusually large clinical trials released recently.
In the developing world, widespread vaccinations would significantly decrease the 600,000 fatal cases annually of children younger than 5, experts said. In the United States, where readily available medical care limits deaths to about 40 a year, routine vaccine use could eliminate most of the 70,000 disease-related hospitalizations and 87 per cent of the workdays missed by parents, saving billions of dollars, according to the studies, published in the current New England Journal of Medicine.
“After a long period of waiting, the time for a rotavirus vaccine may have finally arrived,” wrote Drs Roger I. Glass and Umesh D. Parashar of the Centres for Disease Control and Prevention in a journal editorial. The two vaccines were developed in response to the 1999 withdrawal of RotaShield, a vaccine with a rare but potentially fatal side effect. Even countries with numerous rotavirus deaths shunned the vaccine as a consequence.
The new clinical trials should boost confidence in vaccination in the US and abroad. Africa and Asia account for 85 per cent of all rotavirus deaths. Acceptance in the US is “critically important”, added Dr Jon Kim Andrus of the Pan American Health Organization in Washington, DC. “A lot of countries develop their policy because of the experience accumulated over the years in the US.” — Dawn/LAT-WP News Service (c) Los Angeles Times
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