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Designer glasses correct red-green colour blindness
Jenny E. Ross/corbis
IN BRIEF Diabetic dogs cured by gene therapy
Arctic sunshine cranks up the greenhouse gas threat IT’S a solar double whammy. Not only does sunlight melt Arctic ice, but it also speeds up the conversion of frozen organic matter into carbon dioxide. The amount of carbon in dead vegetation preserved in the far northern permafrost is estimated to be twice what the atmosphere holds as CO2. Global warming could allow this plant matter to decompose, releasing either CO2 or methane – both greenhouse gases. The extent of the risk remains uncertain because the release mechanisms are not clear. Rose Cory at the University of North Carolina at Chapel
Hill and her colleagues analysed water from ponds forming on melting permafrost at 27 sites across the Arctic. They found that the amount of CO2 released was 40 per cent higher when the water was exposed to ultraviolet light than when kept dark. This is because UV light, a component of sunlight, raises the respiration rate of soil bacteria and fungi, amplifying the amount of organic matter they break down and the amount of CO2 released (PNAS, DOI: 10.1073/pnas.1214104110). The thawing Arctic is emerging as a potentially major source of positive feedback that could accelerate global warming beyond existing projections. “Our task now is to quantify how fast this previously frozen carbon may be converted to CO2, so that models can include the process,” Cory says.
Plants listen more keenly to close kin IT IS not just humans that like a natter with their nearest and dearest – plants pay most attention to their closest relatives. When an insect bites a leaf, many plants release volatile chemicals to prime their neighbours for attack. Now Richard Karban of the University of California, Davis, has shown that for the sagebrush, responses to these warning signals can vary with relatedness. 18 | NewScientist | 16 February 2013
At the start of three growing seasons, Karban’s team exposed different branches of the same plants to volatile chemicals. The substances came from relatives of the same species whose leaves had been clipped to trigger chemical release. By the end of the seasons, herbivores had done less damage to the branches exposed to chemicals from close relatives than to those receiving signals
from more distant relatives – the warning probably prompting the plants to release herbivoredeterring chemicals. Karban has previously shown that the blend of volatiles varies between families. He thinks this variability is being used by the plants as a family-specific “key” (Proceedings of the Royal Society B, DOI: 10.1098/rspb.2012.3062). “It is very elegant work,” says Susan Dudley from McMaster University in Ontario, Canada.
FIVE diabetic beagles no longer needed insulin injections after being given two extra genes, with two of them still alive more than four years later. “This study is the first to show a long-term cure for diabetes in a large animal using gene therapy,” says Fàtima Bosch, who treated the dogs at the Autonomous University of Barcelona, Spain. The two genes work together to sense and regulate how much glucose is circulating in the blood. People with type 1 diabetes lose this ability because the pancreatic cells that make insulin, the body’s usual sugar-controller, are killed by their immune system. Delivered into muscles in the dogs’ legs by a harmless virus, the genes appear to compensate for the loss of these cells. One gene makes insulin and the other an enzyme that dictates how much glucose should be absorbed into muscles (Diabetes, doi.org/kf3).
Glasses correct colour blindness LENSES developed to help doctors spot veins more easily have a useful side effect – they enhance the ability to see reds and greens. The glasses, made by 2AI Labs in Boise, Idaho, use filters to enhance perception of blood-oxygen levels in vessels under the skin. The filters concentrate their effects around the wavelengths where people with red-green colour blindness have deficiencies. “We didn’t design them for colourblind people,” says Mark Changizi, of 2AI Labs, “but we weren’t too surprised to find they help.” Daniel Bor, a colour-blind neuroscientist at the University of Sussex in Brighton, UK, tried the specs. “They made my daughter’s lips and her red-orange jumper really stand out,” he says.
IN BRIEF Diabetic dogs cured by gene therapy
Arctic sunshine cranks up the greenhouse gas threat IT’S a solar double whammy. Not only does sunlight melt Arctic ice, but it also speeds up the conversion of frozen organic matter into carbon dioxide. The amount of carbon in dead vegetation preserved in the far northern permafrost is estimated to be twice what the atmosphere holds as CO2. Global warming could allow this plant matter to decompose, releasing either CO2 or methane – both greenhouse gases. The extent of the risk remains uncertain because the release mechanisms are not clear. Rose Cory at the University of North Carolina at Chapel
Hill and her colleagues analysed water from ponds forming on melting permafrost at 27 sites across the Arctic. They found that the amount of CO2 released was 40 per cent higher when the water was exposed to ultraviolet light than when kept dark. This is because UV light, a component of sunlight, raises the respiration rate of soil bacteria and fungi, amplifying the amount of organic matter they break down and the amount of CO2 released (PNAS, DOI: 10.1073/pnas.1214104110). The thawing Arctic is emerging as a potentially major source of positive feedback that could accelerate global warming beyond existing projections. “Our task now is to quantify how fast this previously frozen carbon may be converted to CO2, so that models can include the process,” Cory says.
Plants listen more keenly to close kin IT IS not just humans that like a natter with their nearest and dearest – plants pay most attention to their closest relatives. When an insect bites a leaf, many plants release volatile chemicals to prime their neighbours for attack. Now Richard Karban of the University of California, Davis, has shown that for the sagebrush, responses to these warning signals can vary with relatedness. 18 | NewScientist | 16 February 2013
At the start of three growing seasons, Karban’s team exposed different branches of the same plants to volatile chemicals. The substances came from relatives of the same species whose leaves had been clipped to trigger chemical release. By the end of the seasons, herbivores had done less damage to the branches exposed to chemicals from close relatives than to those receiving signals
from more distant relatives – the warning probably prompting the plants to release herbivoredeterring chemicals. Karban has previously shown that the blend of volatiles varies between families. He thinks this variability is being used by the plants as a family-specific “key” (Proceedings of the Royal Society B, DOI: 10.1098/rspb.2012.3062). “It is very elegant work,” says Susan Dudley from McMaster University in Ontario, Canada.
FIVE diabetic beagles no longer needed insulin injections after being given two extra genes, with two of them still alive more than four years later. “This study is the first to show a long-term cure for diabetes in a large animal using gene therapy,” says Fàtima Bosch, who treated the dogs at the Autonomous University of Barcelona, Spain. The two genes work together to sense and regulate how much glucose is circulating in the blood. People with type 1 diabetes lose this ability because the pancreatic cells that make insulin, the body’s usual sugar-controller, are killed by their immune system. Delivered into muscles in the dogs’ legs by a harmless virus, the genes appear to compensate for the loss of these cells. One gene makes insulin and the other an enzyme that dictates how much glucose should be absorbed into muscles (Diabetes, doi.org/kf3).
Glasses correct colour blindness LENSES developed to help doctors spot veins more easily have a useful side effect – they enhance the ability to see reds and greens. The glasses, made by 2AI Labs in Boise, Idaho, use filters to enhance perception of blood-oxygen levels in vessels under the skin. The filters concentrate their effects around the wavelengths where people with red-green colour blindness have deficiencies. “We didn’t design them for colourblind people,” says Mark Changizi, of 2AI Labs, “but we weren’t too surprised to find they help.” Daniel Bor, a colour-blind neuroscientist at the University of Sussex in Brighton, UK, tried the specs. “They made my daughter’s lips and her red-orange jumper really stand out,” he says.