Short Science, May 25, 2014

PUBLISHED : Sunday, 25 May, 2014, 4:25am
UPDATED : Sunday, 25 May, 2014, 4:57am

Farms feed insatiable demand for fish

Humans have never eaten so much fish and other seafood, and nearly half of it is now grown in farms. The UN's Food and Agriculture Organisation says while 80 million tonnes of fish were caught "wild" in 2011-12, aquaculture production set another high at more than 90 million tonnes. The world harvested an extra 10 million tonnes of aquatic food in 2012 compared to 2011. "Fish farming holds tremendous promise in responding to surging demand for food," the report says. The UN is upbeat on fish stocks, identifying a marginal drop from 30 per cent to 28.8 per cent in over-exploitation. The Guardian


Global space spending up 4pc despite US cut

Global spending on space grew 4 per cent last year to US$314 billion. Spending on satellites, launches and support services increased to US$314 billion, up 4 per cent, even though the US cut its space spending. Commercial space activity, including rocket launches to fly cargo to the International Space Station, fuelled most of the growth, the US Space Foundation report said. Reuters


Blast waves studied as means to fight fires

Australian researchers are working on fighting out-of-control bushfires with explosives. They liken the process of using the sound waves produced by a blast to blowing out a candle. Graham Doig, of Sydney's University of New South Wales, has been examining how blasts can extinguish fires, a technique sometimes used on oil well blazes. His team detonated an explosion in a four-metre steel tube to produce a shockwave and rush of air aimed at a metre-high flame fuelled by a propane burner. "The sudden change in pressure across the shockwave, and then the impulse of the air flow behind it, pushed the flame straight off the fuel source," he said. "As soon as the flame doesn't have access to fuel any more, it stops burning." AFP


Female rats 'not too hormonal for lab tests'

Is the science of biology sexist? Writing in the journal Nature, the director of the US National Institutes of Health admonished scientists for testing drugs and theories on male lab rats, tissues and cells, while excluding females for fear their hormone cycles might distort results. Research, the authors wrote, suggests females' cycles are no more distortionary than males'. Now all studies that apply to the NIH will be vetted for an appropriate balance of male and female subjects. The Guardian