Posts Tagged ‘gamma rays’
An American company has developed a technique that it says can make bread stay mould-free for 60 days. The bread is zapped in a sophisticated microwave array which kills the spores that cause the problem.
The company claims it could significantly reduce the amount of wasted bread – in the UK alone, almost a third of loaves purchased.
The technique can also be used with a wide range of foods including fresh turkey and many fruits and vegetables.
Food waste is a massive problem in most developed countries. In the US, figures released this year suggest that the average American family throws away 40% of the food they purchase – which adds up to $165 billion annually.
Bread is a major culprit, with 32% of loaves purchased in the UK thrown out as waste when they could be eaten, according to figures from the Department for Environment, Food and Rural Affairs…
In normal conditions, bread will go mouldy in around 10 days. But an American company called Microzap says it has developed a technique that will keep the bread mould free for two months.
At its laboratory on the campus of Texas Tech University in Lubbock, chief executive Don Stull showed off the long, metallic microwave device…Originally designed to kill bacteria such as MRSA and salmonella, the researchers discovered it could kill the mould spores in bread in around 10 seconds.
“We treated a slice of bread in the device, we then checked the mould that was in that bread over time against a control, ” he explained. “And at 60 days it had the same mould content as it had when it came out of the oven…”
…There is also a concern that consumers might not take to bread that lasts for so long. Mr Stull acknowledges it might be difficult to convince some people of the benefits.
NSS! If it wasn’t a concern – we’d already be using less-expensive gamma radiation to produce the same result. My friends in the organic wing of the foodie religion are thoroughly capable of crapping their jeans over any scientific method of destroying harmful critters in our food.
It doesn’t matter how many tests demonstrate no residue left behind from any sort of radiation used to sterilize a food product. They will remain convinced that little atomic rays are still whizzing about inside the bread crust ready to turn us into green mutants with vestigial gill covers. Lazy-ass journalists and editors will slop their fears out into the general public because, after all, tales of panic are profitable.
Not wasting food might be worth considering, as well. Naw. That’s probably unAmerican.
In 1054, a supernova went off in our galactic neighborhood and was recorded in a number of historical accounts. Today, the remnants of that blast form the spectacular Crab Nebula shown above. Buried within it is a rapidly rotating neutron star, which we can detect by its pulsed emissions. Now, researchers have used a rather unusual telescope — one that incorporates our own planet into the optics—to catch a glimpse of the pulsar using very high energy gamma rays…
The Crab Nebula, being only about 1,000 years old, contains a pulsar that’s both spinning rapidly and is relatively close to us, which makes for an excellent test of various theories about neutron star behavior. Based on measurements from other pulsars, it has looked like pulsar emissions tended to remain fairly even until they hit energies of 100MeV to a few GeV, at which point they underwent an exponential decay (above those energies, emissions rapidly tail off and there are few photons of higher energies). Observations of the Crab Nebula had picked up a few high energy photons, but these were erratic and not clearly packaged into pulses, so they simply set an upper limit on possible emissions at high energies.
To get a better view of this pulsar, a research team turned to telescope called VERITAS, located in the Arizona desert. VERITAS consists of four 12m telescopes, but these are never focused on the stars. Instead, they are used to detect light in the Earth’s atmosphere that is caused by incoming gamma rays.
When a highly energetic gamma ray strikes the atmosphere, it sets off a shower of energetic particles, some of which end up moving faster than the speed of light in that medium. The particles (at least, the ones that aren’t neutrinos) slow down rapidly by emitting light called Cherenkov radiation. Telescopes like VERITAS use this light to reconstruct the path of the particles back to the source, providing information about its direction and energy. In short, the entire atmosphere gets used as something roughly analogous to a CCD…
…When the data was analyzed, a clear pattern of pulses became apparent at energies above 120GeV, and the timing of the pulses lined up nicely with observations at lower energies made using the Fermi space telescope. The object there is pulsing at much higher energies than any previously detected…
In any case, the authors make a compelling case that we should be looking at the Crab Nebula at higher energies than we generally do, since a careful study of gamma rays may help us constrain or eliminate various models of neutron stars. And, if possible, looking at other pulsars might give us a greater sense as to whether the one in the Crab Nebula is an anomaly.
And it rocks!
A space telescope has accidentally spotted thunderstorms on Earth producing beams of antimatter.
Such storms have long been known to give rise to fleeting sparks of light called terrestrial gamma-ray flashes.
But results from the Fermi telescope show they also give out streams of electrons and their antimatter counterparts, positrons…
It deepens a mystery about terrestrial gamma-ray flashes, or TGFs – sparks of light that are estimated to occur 500 times a day in thunderstorms on Earth. They are a complex interplay of light and matter whose origin is poorly understood…
The Fermi space telescope is designed to capture gamma rays from all corners of the cosmos, and sports specific detectors for short bursts of gamma rays that both distant objects and TGFs can produce…
“One of the great things about the Gamma-ray Burst Monitor is that it detects flashes of gamma rays all across the cosmic scale,” explained Julie McEnery, Fermi project scientist at Nasa.
“We see gamma-ray bursts, one of the most distant phenomena we know about in the Universe, we see bursts from soft gamma-ray repeaters in our galaxy, flashes of gamma rays from solar flares, our solar neighbourhood – and now we’re also seeing gamma rays from thunderstorms right here on Earth,” she told BBC News…
But within that gamma-ray data lies an even more interesting result…”the discovery that TGFs produce not just gamma rays but also produce positrons, the antimatter equivalent to electrons…”
Steven Cummer, an atmospheric electricity researcher from Duke University in North Carolina, called the find “truly amazing”.
“I think this is one of the most exciting discoveries in the geosciences in quite a long time – the idea that any planet has thunderstorms that can create antimatter and then launch it into space in narrow beams that can be detected by orbiting spacecraft to me sounds like something straight out of science fiction,” he said.
“It has some very important implications for our understanding of lightning itself. We don’t really understand a lot of the detail about how lightning works. It’s a little bit premature to say what the implications of this are going to be going forward, but I’m very confident this is an important piece of the puzzle.”
RTFA for detail on the mechanisms and processes involved. As far as we know.
There are some talented, knowledgeable folks working away on this and waiting for their periodic reports is as tantalyzing as being a kid standing outside the neighborhood drugstore waiting for the next issue of Thrilling Wonder Stories to arrive.