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The Breaking Science team come to BBC Radio Five Live to break open this week's science stories.

I’ve worked with DNA for decades and it comes as shock when someone generates a living animal from the equivalent of those peas that float around the bottom of your freezer! A mouse that had sat in a freezer 16 years with no preservatives has genetic material intact enough for researchers to use the cloning technique to create a living cell and from there, a mouse. Just how the DNA survived the rigours of being frozen, something that is usually guaranteed to sheer and destroy these long biomolecules, is unknown.

As is usual with cloning, the report has induced wild speculation about resurrecting the mammoth from Siberian frozen tissues, even though analyses of DNA from extinct organisms such as dodos, frozen mammoths, bears and even Neanderthal teeth, has only ever found DNA degraded into billions of small pieces and well beyond resurrection. Having said that, I wonder whether anyone has actually looked in frozen tissues, rather than assume the DNA is all degraded and simply extract it biochemically, a process which sheers it to bits anyway. Of course the other critical stages in cloning are the recipient egg and the mother to carry the embryo, so if someone is really going to try and resurrect a mammoth then I guess the world’s elephant reproductive biologists had better step forward.

It is a fascinating development and one that is likely to find interesting future applications. But two messages. First, don’t take these findings as a go ahead to ignore those little snowflakes on the frozen pizza that tell you to only keep it 3 months (food poisoning is not fun). Second, when you’re next cleaning-out the freezer, if you do find a frozen extinct animal rolling around with the peas then keep it safe; you might be able to supply some lab with the next scientific breakthrough.

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Ep8: Frozen clones, friendly bacteria, Dalmations...

The Next Big Thing: Cloning

'Production of healthy cloned mice from bodies frozen at -20°C for 16 years'
by Sayaka Wakayama, Hiroshi Ohta, Takafusa Hikichi, Eiji Mizutani, Takamasa Iwaki, Osami Kanagawa, and Teruhiko Wakayama.
Published in PNAS, 11^th November 2008

About the author

Dr Mark Hirst is a senior lecturer in human genetics at The Open University. He's been working in molecular biology for over 25 years, focussing on genetics of human neurological diseases, especially those that involve DNA synthesis, damage and repair.

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Blogging about

Breaking Science

The Breaking Science team come to BBC Radio Five Live to break open this week's science stories.

Volcano tectonic seismicity occurs as Earth’s crust is deformed and fractured by magma movement. It results in shallow-focus earthquakes beneath the volcanic edifice, that frequently provide the first sign of growing unrest. Faulting provides conduits between the deep reservoir and the surface, and the final approach to eruption is commonly preceded by an increase in the number of low-magnitude volcano-tectonic earthquakes.

Swarms of low frequency seismic events seem to be related to fluid movement. When swarms last so long that they run into each other and become a continuous seismic disturbance, it’s called volcanic tremor. It’s been suggested that the identification of these low frequency events can be used as a method in eruption prediction.

To obtain a greater understanding of the processes involved in the creation of seismic signatures, a series of laboratory deformation experiments were carried out using samples from lavas erupted from Etna volcano. In the experiments, the rock samples were deformed and fractured using pressures similar to those found deep beneath volcanic edifice, generating a network of cracks, which were then filled with fluids. The seismic signals generated by the process were recorded.

It’s previously been thought that low frequency events are due to resonance within cracks or volcanic conduit flow. This new simulation however, suggests that these events in volcanic areas are generated when hot fluids, such as water, steam and/or magma itself move through a network of pre-existing cracks. A better understanding of volcanic seismicity offered by this study may help with the future interpretation of seismic signals, with benefits for volcanic hazard evaluation and mitigation.

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Episode 4: Malaria, volcanoes...

‘Laboratory Simulation of Volcano Seismicity’
by PM Benson, PG Meredith RP Young, S Vinciguerra
in Science

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Breaking Science

The Breaking Science team come to BBC Radio Five Live to break open this week's science stories.

There is currently no satisfactory explanation of how planets form but it seems that conditions of extremely high temperatures and concentrations of matter are required. Recent experiments have produced matter at extreme conditions similar to those found in space when planets form.

In a recent experiment, detailed in Science, researchers investigated the changes in lithium-hydride, a material which is flammable in air and explodes when it comes into contact with water. They used a high-powered laser to deliver a very large amount of power for a very short time, creating huge sparks, or shocks, of energy within the target material.

The lithium-hydride was monitored using a powerful x-ray probe to detect the different stages that materials undergo during very rapid changes. It was found that the shock-wave produced extreme temperatures and pressures, up to 25000k and a compression factor of 3. This ability to monitor such fast, extreme conditions will enable further laboratory testing of planetary formation and modelling of planetary composition.

Find out more

Episode 3: HIV, superstitions...

'Ultrafast X-ray Thomson Scattering of Shock-Compressed Matter'
by Andrea L Kritcher, Paul Neumayer, John Castor, et al
in Science 322 pp69

Three o’clock Sunday afternoon, we leave Milton Keynes with the car loaded up with equipment.

"We" are John Zarnecki, Professor of Space Science, and Karl Atkinson, PhD student, both from the OU’s Planetary and Space Sciences Research Institute.

"The equipment" is an aluminium contraption about two and a half metres high, of tripod shape with a horizontal arm that can drop a sensor from various heights.

We are off to Chesil Beach, on the coast of Dorset. Why are two planetary scientists going to the Dorset coast?

Obviously, because Chesil Beach is like the surface of Titan, Saturn’s largest moon!

The drop rig at Chesil beach on an earlier (sunny!) trip.

Let’s explain. On January 14, 2005, the European Space Agency’s Huygens probe landed on the surface of Titan after a seven and a quarter year, three and a half billion kilometre journey.

The first part of the probe to strike the surface was a penetrometer, part of the Surface Science Package (SSP). SSP was one of the 6 scientific instruments carried by Huygens. For about 12 milli-seconds (12/1000th of a second), the penetrometer - essentially an instrument "stick" about 10 cm long - was the only part of the Huygens Probe which was in contact with the surface, as the rest of the probe floated down to the surface under its parachute.

At the point the approximately 300 kg probe struck the surface, and from that time on, the penetrometer signal (essentially a measurement of force against time), becomes nearly impossible to interpret. But the brief ‘clean’ signal can give a clue as to the nature of Titan’s previously unseen surface.

Karl Atkinson had started his PhD at the Open University just a few months before Huygens arrival at Titan. He had been given the task of preparing for the receipt of this precious signal (before we could even be sure that the probe would survive the perilous descent and landing).

He collected a range of reference material signatures – including those of various sands, gravels, clays and some more exotic materials. The purpose was to represent, in terms of mechanical properties for example, the range of surfaces which had been predicted for Titan. Remember that Titan is basically an icy body that was predicted to be possibly covered by a layer of organic sludge, or even lakes or seas of liquid methane.

The surface of Titan imaged by the Huygens probe.

[image © copyright ESA/NASA/JPL/University of Arizona]

When January 14 came and went, Huygens behaved almost immaculately – and the penetrometer collected its precious data. The on-board camera showed that Huygens had landed on what looked like the shore of a dried-up lake bed. Some "pebbles" were visible sitting on top of a surface which could not be fully resolved by the camera. So what was it?

This was the question faced by Karl for his PhD project. His basic interpretation was that the penetrometer, after at first producing a brief high force signature had pushed into a soft surface. From his work in the laboratory, it seemed that the material on Titan was probably granular or grainy. Could it be Titan’s version of sand or gravel, produced by the continued action of flowing liquid over the underlying bedrock - which, in the case of Titan, would be methane flowing over ice?

He produced many sample surfaces in the laboratory but knew that natural processes on Earth would be better at producing some realistic ‘targets’ for Titan. For example, the roughly 18 mile-long Chesil Beach offers a whole range of different local granular environments – from well-sorted cobbles through to coarse sand.

Furthermore, regions were found where the beach had distinctive layers lying on top of each other that could be seen in the penetrometry signature. Of course, Titan’s surface material is ‘icy’ rather than ‘rocky’ but ice at -179^oC has similar mechanical properties to rocky material on Earth’s surface.

So, in the early part of 2008, a programme of simulated impacts into the range of surfaces offered by Chesil Beach was carried out. But life is never simple. Some of the data was unexpected and needed to be double-checked.

So, on 20th October 2008, we found ourselves on the beach to carry out a selection of "simulated drops" close to the actual impact speed on Titan, 4.6 metres per second. These tests were done in the face of a raging gale -inhospitable, but not quite as bad as Titan itself!

Using the beach drops and previous results from laboratory work, an estimate of the material grain size at each site was made and compared with the actual sizes observed. Accounting for the difference in density between the sand on the beach and the presumed water ice on Titan’s surface, this work suggests that the grains at the Huygens landing site are similar in size to coarse sand such as that found at the western end of Chesil beach.

Furthermore, in several signatures we were able to determine the depth and thickness of distinct layers and material grading (grains being sorted with depth) caused by wave action on the beach surface. These features however are not seen in the Titan signature.

Flight data returned by the penetrometer from the surface of Titan, showing time in milliseconds against force in Newtons.

This all helps to build up the picture of what we think the surface of Titan is like and may help understand the physical processes at the landing site. Remember that these data from Huygens won’t be improved on for at least 20 years - when we hope to return to Titan with an even more ambitious mission.

Find out more

Stardate: Mission To Titan - our space series reported on the mission
Mission to Brighton - finding penetrometers impenterable? Try our interactive explanation.

It had been one of those research trips where everything was going wrong. We were four weeks into a five week field trip to Mount Etna and we had not finished the levelling, dry tilt or GPS measurements. We'd lost precious time with three weeks of ice and early snowfalls that made work at the summit impossible, and our trusty, 17-year old digital level had let us down. The manufacturer had been good enough to send us a replacement, but that took a stressful five days, and to cap it all Etna had decided she would send a lava flow to destroy one of our treasured stations that I had installed 21 years ago.

The last thing I wanted to do was spend a day being nice and polite to the BBC.

Studying Mount Etna.

On the day of the BBC's arrival the weather was perfect. Their plane was to land in the afternoon, but with things as they were we couldn't waste the opportunity, so at first light we set off for the summit of Etna.

Andy Bell, a seismologist from Edinburgh, was leaving us the following morning, so it was our last day with five people, and thus our last chance to measure the critical stations in the Valle del Bove.

This was a borderline-dangerous escapade down into a vast cauldron five kilometres wide and one kilometre deep, that, for the previous five months, had been filling up with flow after flow of loose Aa lava: red-hot piles of loose unstable stones sharp as glass.

On a good day this would have taken a solid eight hours of hard slog, but this was not a good day.

The new lava had made the task almost impossible, so after ten hours we were still floundering around in pitch darkness, out of radio and mobile phone contact, with the streams of lava glowing behind us in the darkness.

When at last we limped bruised and bleeding over the lip of the valley, Material World producer Martin Redfern's voice over the phone was a paradigm of polite restraint. "Delighted to make contact…" etc, etc.

The Material World team get an interview.

Not only had we not been there to meet them, and uncontactable to boot, but it transpired that I had given them the wrong website for their Bed-&-Breakfast, so instead of being round the corner from us in Nicolosi, the highest village on the volcano, they were 20 miles away in Adrano, at the foot of the mountain. Oh dear, oh dear, oh dear, and a lot of swearing…

The following morning was a different kettle of fish. We were scarcely half an hour late when we finally met Martin and presenter Quentin Cooper at the Sapienza halfway up the south side, from where we began the slow ascent up the vehicle track to the top, with six of us crammed into our 4x4, together with seven GPS kits, tripods and rucksacks.

The nature of the work, and the difficult and sometimes dangerous conditions, means that at least 4 people (2 teams of 2) are required. This year there is Saskia van Manen, a Dutch PhD student at the Open University, Melanie Zacheis, completing her Masters at Portsmouth University, and Kate Gladstein from Vermont University, U.S.A., whose work here on Etna will form part of an undergraduate project.

Etna does not always erupt its lava from the summit craters. Now and again a new fissure opens in the side of the mountain, and this had happened in May, and the lava was still sluggishly oozing out. Before the main business of the day, we took an hour's scramble to look at how the eruption was progressing.

It's wise to keep a gas mask to hand.

We were able to stand on the edge of the erupting fissure, with acrid sulphur dioxide and hydrogen sulphide pouring from the abyss, but there was total silence, and no sign of flowing lava. Only when the mist cleared could we see the bluish gas and the deep red of the active flows far below us in the Valle del Bove. Between us and the flows the lava was travelling through a series of underground channels.

Our work concentrates on measuring with extremely precise instruments how the volcano changes shape from year to year, as the magma forces its way from deep within the volcano to the surface, and as portions of the volcano slide downhill or jostle in response to shifting gravitational or tectonic forces. I have been doing this once to three times a year since 1975, and this year we have already found some exciting results.

Not only has much of the land on this eastern side shifted more than one metre towards the sea, but there has also clearly been an injection of magma down the north side of the volcano, deep beneath the surface.

We measure vertical movements and ground tilt of more than 300 stations over the summit and flanks of this huge volcano with a precise level - now old and venerable technology, but still twenty times more accurate than any other method of height measurement.

However with six of us in the vehicle we have had to leave this equipment behind. Today we would be using dual-frequency GPS, capable of measuring our 100 stations to an accuracy of a few millimetres over distances of tens of km. Up to seven GPS kits are set up at stations all over the mountain at the same time, and left running for between 20 minutes and ten hours.

As the recording got under way, it became clear that this is to be at least partly a fly-on-the-wall affair, with the odd more structured interview.

We approached the first GPS station, the microphone was switched on, but as the girls began to set up the equipment a thought crossed my mind, and I nipped across to obstruct the view of the handset, but too late.

Quentin opened with "I can't help noticing that the name of this station is 'Clenched Buttock'…". Oh dear, oh dear, hope they cut that bit out.

Students have been naming these stations now for nearly 40 years, and they range from the poetic to the nostalgic to the comic to the downright rude, but they were all topical at the time and all have a story to tell, and bring back more than anything the flavour of trips long past: Crack of Doom, Eleanore's dream, Cat's Paw, Desolation, Lightning Ridge, Big Girl's Blouse, Defenestration, Sellotaped Egg, Monkey Boy, Chocky's Hill, and the greatly-regretted Rosanna, now buried deep beneath the accumulating lavas of the 2008 eruption.

We quickly got used to the microphone, even forgot it was there. All in all things seemed to go well, though I was aware of making the occasional gaff. There were countless interviews with me and each of the women, but I still felt we were only scratching the surface, and that only a small part of our work, and of the multi-faceted nature of Mt Etna and its eruptions, was being recorded.

At the end of the day we made the ascent to the edge of two of the four summit craters.

An otherworldly vista.

Normally one can hear explosions or at least puffs of gas deep down inside, but there was still total silence, so Radio 4 listeners will have to be content with descriptions of the yellow sulphurous deposits and our coughing fits as the wind takes the gas in our direction now and again.

The BBC's visit marked a turning point in the trip. After they had gone, the weather changed to its normal calm, sunny, autumnal best, and in the final few days we managed to get everything completed.

Take it further

The Material World from BBC Radio 4 and The Open University

The BBC's Martin Redfern reported on this trip for From Our Own Correspondent
Listen to Martin's report

Discover the science behind volcanic eruptions

How was the entire continent affected by the 1783 Laki eruption on Iceland?

Explore volcanoes on the surface of Venus

Study science with the Open University

About the author

John Murray has been working for nearly 40 years studying the active volcanoes of Mount Etna. He commenced a long-term study in 1975, the longest continuous study of an active volcano conducted by an individual. John predicted the 1983 eruption a year before it happened. He joined The Open University in 1989, working on planetary science and volcanoes.

View John’s recent research publications by visiting John's entry in Open Research Online – a collection of The Open University’s published research.

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Over the weekend, some family and friends came down to visit us on the Isle of Wight, and stopped a mile or so away in a hotel in Seaview overlooking the Solent. With binoculars in hand, the sea view rooms looked out onto the passing sea traffic - ferries to France, cruise liners going in to Southampton, warships heading for Portsmouth and all manner of freightliners heading for who knows where.

To add to the seaside experience, the hotel menu also posts times of when the cruise ships are passing by so you can look out for them over dinner! These details are also posted in the Island's local newspaper and are presumably "public information".

Now one of the things that I love about the way the web is going is that it's getting easier to access "live data". From traintimes, to what's on the telly now, from roadworks on the M1, to the latest share prices, I can increasingly find out "what's happening now". So I had a look around to see if live shipping data is available from anywhere.

Now it turns out that it is, and it's provided by a system called AIS, the Automatic Identification System. It apparently works like this: each AIS enabled ship has an AIS transponder that incorporates: VHF receivers for receiving AIS information from other ships; a unit that provides integratoin with other shipboard systems (such as GPS and navigation systems); and a transmitter that transmits AIS data. (For a more technical description, there's a "how it works" explanation on the US Coastguard website.)

The transmitted AIS data includes at least a unique identifier for the vessel, location information, and the heading, course and speed information. This information can then be displayed on a map or other location revealing display.

Anyone with an appropriate receiver can receive the AIS data, and with a little bit of tinkering they can then display this information on a map. And it turns out that some enterprising folks around the Solent have done just that: Solent Area Ship Tracking.

Each balloon represents a separate vessel, as identified from its AIS data. So next time family and friends are down, and staying in Seaview, I can point them to the live shipping data map and they can find out a little bit more about each ship as it passes by :-)

Just a note of warning though - checking ship locations using a web based service like this should not be relied on if you're out sailing - the data may be stale (that is, out-of-date) or cached by your browser. The only guaranteed true picture will be one where you have grabbed the AIS data yourself from over the airwaves and then plotted it out, at the time, yourself...

The story isn't quite finished though. Firstly, there's a prequel as to how I found the map - rather than doing a badly specified websearch, (I didn't know AIS existed a week ago!) I asked a question on Twitter. Twitter? A web based short messaging service that sits somewhere between instant messaging, email and SMS text messaging! (For a quick tutorial, see this CommonCraft video: Twitter in Plain English.)

[video by Commoncraft]

As with many other social networking sites, Twitter supports "friending", in the sense of following the posts that other people make. So I posted a question in the hope that some of the people from the Isle of Wight I follow (and who follow me) would know whether such a map exists. And they did, and so that's how I got the link to the map shown above!

And secondly? Secondly there's a wishlist item for something I'd like to be able to see (and do). A way of uploading a photograph of each a ship to the web, tagging it in some way, and then being able to click on the marker for that vessel and see the photos of it (ideally along with a timestamp and location data from where the boat was when the picture was taken). Then it would be possible to 'anecdotally' start plotting out the route taken by each ship, and for the container ships, maybe even how laden it was entering and leaving each port!

PS the thought of tracking a ship as it circumnavigates the globe reminded me of an 'experiment' being run by the BBC at the moment to track a shipping container over the course of a year - you can find out more here: The Box.

About the author

Tony Hirst is co-founder of the OU Robotics Outreach Group and a lecturer in artificial intelligence at the Open University. Far too much of his time is spent playing with web technologies, developing tools and applications that he claims will be OUseful, one day...

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Blogging about

Breaking Science

The Breaking Science team come to BBC Radio Five Live to break open this week's science stories.

Damage to the spinal cord can block the electrical signals produced by nerve cells in the brain from reaching the muscles required for limb movement. The result is paralysis - the loss of voluntary muscle function. Neuroscientific research by Chet Moritz and his colleagues at Washington University, USA, offers hope for people with paralysing spinal cord and similar debilitating nerve pathway injuries.

In the study, monkeys were trained to control the electrical activity of individual nerve cells in the motor cortex, an area of the brain responsible for voluntary movement whilst they manipulated a cursor on a computer screen during a video game. When the animals had learned to control the cursor, their wrist muscles were temporarily paralysed with anaesthetic which blocked the nerves supplying the wrist. The experimenters subsequently by-passed the nerve block using a brain-computer device, called a ‘neurochip’, to transfer electrical activity directly from nerve cells in the monkeys’ motor cortex to the previously paralysed wrist muscles. As a result, the animals regained control of wrist movement and could continue to successfully guide the cursor in the video game.

These exciting studies pave the way for the future development of brain implants allowing people with paralysed limbs to regain voluntary control of muscle movement. However, as the scientists acknowledge, there is much research to be done before such devices are available in the clinic.

Find out more

Episode 5 of Breaking Science.

‘Direct control of paralysed muscles by cortical neurons’
by Chet Moritz, Steve Perlmutter & Eberhard Fetz
in Nature

About the author

Paul Gabbott is a Senior Lecturer in Neuroscience in the Life Sciences Department of The Open University, Milton Keynes. His research is centred on the structure and function of nerve cells in the cerebral cortex.

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