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Global fisheries can be sustained if responsibility for resources is shared between government and users. This is the only tool to save aquatic resources and livelihoods of communities, said researchers who studied 130 fisheries in 44 developed and developing nations. Statistics based on an eight-point rating scale showed that 40 per cent of fisheries scored positively on six, seven or all eight outcomes. It proved that community leadership and social cohesion are vital for co-management. Nature, January 5
Grapes’ health key found
Those who are obese, diabetic and growing older should eat grapes. Grapes contain resveratrol, an antioxidant which provides grapes its healthy properties. The working of resveratrol is not well understood. A study found that resveratrol triggers the expression of adiponectin, a beneficial hormone derived from cells that manufacture and store fat. Adiponectin can be targeted to treat obesityrelated complications.
Journal of Biological Chemistry, January 7
DVD storage secret out
It is now known how DVDs store data. The polycrystalline data layer in a DVD is made of germanium or silver, antimony and tellurium. The materials are either disordered, amorphous or ordered, crystalline in structure. During storage, laser action triggers a transition between these two phases. Knowledge of how these phases co-exist can lead to better materials that result in DVDs with a larger space and longer life.
Nature Materials, January 9
Blow hot, blow cold
Cool weather can make female butterflies disobey the courtship rules. Entomologists have found that in a sexual role reversal female Bicyclus anynana exposed to cool, dry temperatures as caterpillars actively court males as adults. The females use reflective eye spots on their wings to attract potential mates. On the other hand, raised in moist and warmer season as larvae, males take up the traditional roles of suitor, displaying their wing designs to attract females. The study is the first to show that butterflies develop sexual ornamentation in response to the temperatures of the environment.
Science, January 7
How healthy is organic?
Absence of toxic chemicals might be the only advantage that organically grown vegetables have for consumers. Health benefits of organic food consumption are still controversial and not scientifically well-documented. Earlier studies have shown that organic foods are richer in beneficial compounds like polyphenols. But when researchers analysed the antioxidants in two separate samples of onions, carrots and potatoes—one grown using organic methods and the other grown using fertilisers and pesticides, they did not find any difference in polyphenol levels. Polyphenols are chemicals that protect against common health problems and some effects of aging.
Journal of Agricultural and Food Chemistry, January 5
Quick test for Alzheimer’s
Alzheimer's can now be detected early with a quick blood test. The test can diagnose Alzheimer's, multiple sclerosis, Parkinson's and cancer. It is based on detection of disease- specific antibodies in the blood. The method identified three peptoids that distinguish between healthy and Alzheimer's blood samples with high accuracy. The test might not provide a treatment to terminate Alzheimer's, but detecting the disease three to five years prior to symptoms would be useful for enrolling into clinical trials with drugs showing greater effect in the initial stages. Cell, January 7
Moon’s earthy core
Just as earthquakes tell us about the structure of the earth’s interior, seismic waves of “moonquakes” can help probe the lunar interior. A team of NASA researchers reanalysed seismographic data and found that the moon has an ironrich core with a solid inner ball, nearly 241 kilometres in radius, and an 88.5 km-thick outer fluid shell. The research also suggested that the lunar core possesses a small percentage of light elements like sulfur, similar to light elements in the earth’s core. Scientists speculate that the moon’s interior could hold clues to the earth’s origins.
Science, January 6
Power of household waste
Household sewage has 20 per cent more potential as an alternative energy source than thought earlier. This can spur efforts to extract methane, hydrogen and other fuels from this untapped source of energy. A research estimates that one gallon of wastewater can light a 100-watt bulb for nearly five minutes. The only other study done on wastewater’s energy potential had shown low results because some energy-rich compounds were lost to evaporation.
Environmental Science & Technology, January 15
Sulphur turns magma golden
A recent research has shown how the gold-rich magma in gold mines is produced. The study revealed that this magma is generated in the earth’s mantle, which contains high amounts of sulphur. Noble metals like gold are transported by magma from deep within the mantle of the earth to the shallow crust where they form deposits. These results could help in choosing geographic targets for gold explorations, making them more successful. Through a series of experiments, the team found that sulphur improves the solubility of gold, which is an important step in forming gold deposits. Nature Geoscience, December
Epic turtle journies mapped
A first-ever satellite study has tracked epic ocean journeys undertaken by rare giant leatherback turtles across the South Atlantic. The five-year study on 25 female turtles identified three migratory routes—one of them 7,563 km long— from their largest breeding colony Gabon in central Africa to feeding grounds in south Atlantic and south America. The endangered turtles stay in the feeding grounds for two to five years to build up reserves to reproduce and then return to Gabon. Identifying routes is to save their population in the Atlantic. These routes take them through areas of high risk of fisheries. Collaboration between 11 nations will spur conservation efforts. Proceedings of the Royal Society B, January 5
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