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It’s now three weeks since the Large Hadron Collider (LHC) restarted, after over a year of repairs, and images of scientists clapping and cheering were beamed around the globe.

More celebrations were to follow as the machine smashed proton beams together and then, on 29 November, its beams set a new energy record as they exceeded one TeV, making it the world’s highest-energy particle accelerator.

But what’s it like to be part of such a huge experiment?

To find out I talked to two of the young Oxford University scientists who have been working, living and breathing LHC science.

When particles collide
Hugo Beauchemin and Caterina Doglioni from Oxford’s Department of Physics are both involved in the ATLAS experiment, one of the four detectors which will examine the particles produced from collisions inside the LHC.

‘The LHC is built to look for answers to questions such as why the fundamental particles have mass, or whether the visible matter we see is only a small part of the matter that fills the universe, or why we are made of matter and we see no antimatter in our universe,’ Caterina tells me.

Yet her own research is less about exotic physics and more about seeing where the physics we think we know matches up to real experimental results.

‘I am working on the 'rediscovery' of the standard model we use so far for describing particle physics,’ she explains. ‘First of all we need to be sure the ATLAS experiment works correctly if we want to claim we have an answer to any of the questions above.’

‘And if we are sure everything works, and we still see discrepancies with the current model... then there will be quite a bit of excitement in the physics community!’

Hugo is investigating the extension of that model to see where gravity fits in with the three other fundamental forces of nature: ‘weak nuclear force’ [weak interaction], strong interaction, and electromagnetism.

He tells me: ‘Having done my PhD on the theoretical aspect of the structure of space-time, I’m now leading investigations for LHC evidence of new dimensions of space. In terms of detector operations, I have been centrally involved in studying trigger performance and operation.’

These ‘trigger systems’ are vital to the science going on at the LHC – with so much happening when particles collide, and only a limited amount of storage space for the huge amounts of data generated, automated systems need to decide very quickly what’s ‘important’ or ‘interesting’ and record it.

Hugo feels that, in some senses, the year’s delay wasn’t a complete loss:

‘Despite the disappointment of having to wait an extra year before getting data, I don’t feel that we lost a year… during this last year, a lot of developments on the trigger and data acquisition systems have been made. We are now ready to take good data and to properly store them, which, in my opinion, was not exactly the case last year.’

From frustration to elation
After last year’s frustrations the clock was quickly ticking again as all those involved counted down to the restart.

‘You could feel the excitement growing, everything needed to be ready and working and every possibility had to be explored: which for me means more work coming from a few different directions, not just from my supervisor for physics analysis!’ Caterina comments.

‘I’ve been involved in testing the reconstruction algorithms that allow physicists to decode what the detector registers, and I've written quite a bit of computer software for that so far. It might seem disconnected to the LHC restart, but I knew that I was one of those working towards a common goal, and in my day to day tasks I was also contributing to make all of this work.’

Finally, on Friday 20 November, the LHC was switched back on and successfully circulated two stable proton beams in opposite directions.

So what it was like being there when this giant machine came back to life?

‘Being at CERN is the best place for working as a PhD in particle physics, it feels like we are living at the centre of the world, where everybody converges. And being here at the start-up is like a dream come true!’ Caterina tells me.

‘Even though physicists who work on commissioning the detector with first data from the LHC do not expect a Nobel Prize, seeing a peak that means the rediscovery of a particle that has been known from the 1940s is an amazing experience and it pays back all the work that's been done to prepare for this moment!’

Hugo thinks it may take longer for the sheer magnitude of the occasion to sink in: ‘I was extremely excited, like most of my colleagues, but, to be honest, I didn’t have much time to celebrate. There are so many things need to be checked, studied, monitored, etc. This period is frantic, exciting, but exhausting. I believe that it’s only during the Christmas break that I will have time to realise all that has been accomplished.’

Looking to the future
And for those working on the LHC, exciting as it is, the restart is just the beginning of many years of hard work:

As Hugo points out, despite setting a new energy record, it will take many months to gradually ramp up the energy levels of the LHC to the point where it is likely to make genuinely new discoveries.

He comments: ‘So far it doesn’t provide a sufficient number of collisions for thorough studies of new phenomena, and is even still far from reaching the sensitivity of the Tevatron [a proton vs anti-proton machine, where the LHC is a proton on proton collider]. So this restart gives hope and excitement, but there is still a lot of work to do before being able to achieve anything really new.’

So how do Hugo and Caterina think they will look on this period of their life, dominated by the giant silver machine?

Hugo tells me: ‘Hopefully with a smile: it is a stressful and quite uncertain period. Expectations are high, all eyes are turned toward us, but we don’t know what will be the outcome of this experiment. I hope that in 10 years from now, the LHC will have revealed a large spectrum of unknown phenomena and mysteries to be investigated.’

Caterina adds: ‘I think I will be look back at this time with happiness and pride. I am at CERN, working together with amazingly talented people on something that is an incredible achievement, even because of its start-up alone. There's nowhere else I'd rather be!’

It emerged today that more drivers are using hand-held mobile phones than two years ago, despite the introduction of tougher penalties, BBC News online reports. The Transport Research Laboratory is worried because phone-using drivers are four times more likely to crash and their reaction times are likely to be slower.

It may be that a group of neuroscientists at Oxford University can help in dealing with this kind of distraction and improve drivers’ reaction times. They believe that understanding the way we respond to danger signals and make life-or-death decisions can enable us to make improvements in car design. Leading car manufacturers are now taking an interest in the hope of making us better, safer drivers.

The problem with using a phone is that talking while driving increases the risk of an accident. ‘People think that they can do both, but they can’t,’ says Professor Charles Spence of the Department of Experimental Psychology at Oxford University. ‘The brain is configured to respond best to one spatial location at a time. So looking in one direction at the road and listening in another to a caller on the mobile phone at the same time can’t be done well.’

It is now possible to make transparent loudspeakers which can be incorporated into a car windscreen. This enables people to look at the road and listen to a phone conversation coming from the same direction, Charles Spence’s group has shown.

Senses & signals
There’s no doubt that improvements to driving safety are still needed, with 2,538 people killed on the road in 2008 and 26,034 seriously injured. Human error contributes to the vast majority of road accidents, and loss of control of a vehicle or failing to look properly are contributory factors in many of these incidents.

Many new technologies are gradually being added to cars to improve safety. These include sat-navs, hands-free mobile phones, and warning signals. A number of cars now have systems that can sense nearby vehicles and warn the driver when anything gets too close.

But Charles Spence and colleagues believe that the designs that engineers have come up with - using displays, flashing lights, and bleeps - don’t always make it easy for drivers to make decisions based on the information they’re given.

He believes we can do better: ‘All our decisions and actions are based on our senses and go through our brains. Knowledge of how we respond to sights, sounds, touch and feel should enable us to come up with better, neuroscience-inspired designs for alerting drivers to danger.’

The latest work from Charles’ research group, published in the journal Human Factors, demonstrates how warning signals given to the driver through the headrest can improve the speed with which they can respond to the danger, potentially reducing the number of front-to-rear-end collisions.

The work makes use of recent neuroscience research showing that the space behind the head, where you can’t see what’s going on, is treated in a special way by the brain.

‘Our brains react immediately and automatically to things happening in that space in a defensive response to potential danger.’ says Charles Spence. It is similar to the margin of safety or ‘flight zone’ seen in many animals.

His group, with funding from Toyota, carried out experiments showing a short warning sound from speakers just behind a driver’s head can improve the speed of response to danger by nearly four tenths of a second over warning lights placed further away, like those on a dashboard.

Attracting attention
An alarm signal in the close protective space around the head is better at breaking into the driver’s attention, getting the driver to turn their head to where the danger may be (to look in their side mirror for example), and allowing faster decision-making about the need for braking or avoidance actions.

Charles Spence has also shown that the type of sound and the position of a warning signal matters for the driver’s response time. ‘It is much better to use a car horn as a warning sound rather than a generic electronic beep, because people know what the sound of a car horn means,’ he says. ‘If that sound also comes from where the danger is, rather than on the dashboard, you improve a driver’s response time by four tenths of a second.’

‘Our sense of touch is one of our greatest senses and we don’t use it in driving,’ he adds. His group has investigated incorporating vibrating signals into seatbelts, the driver’s seat, the steering wheel, and the foot pedals. Adding a vibrating warning signal can take another two tenths of a second off response times in driving simulator experiments.

An improvement of five tenths of a second is thought to be enough to reduce front-to-rear-end collisions by 60 per cent, so multisensory warnings that combine vibration, sound, and appropriate location of the signal could make a significant difference to road safety. Volkswagen is hoping to make use of this work.

The neuroscience of our senses could also improve car design in other ways, suggests Professor Spence. ‘The sound of a car’s engine can affect how we think about a car. You may want a car that sounds powerful or sporty, for example. Rather than engineer that satisfying roar into the engine, it may be simpler to subtly change the sound the driver and passengers hear inside the car and improve the way they feel about their driving experience.’

These ideas can be taken further. He adds: ‘You could combine psychology and knowledge of people’s likes and dislikes to introduce smells and fragrances into the car interior to relax passengers or perk them up. You could incorporate this with GPS systems to give fragrances according to the environment you’re driving through. It may even be possible to make the multisensory experience of a car interior so pleasant that you want to stay sitting there even when you’ve reached your destination.’ 

A book currently doing the rounds at the Copenhagen climate talks highlights the impact that biomimetic science could have on medical and green technologies.

Gunter Pauli's The Blue Economy gives the work of Fritz Vollrath of Oxford University's Department of Zoology and the Oxford Silk Group as an example of where learning from nature can pay off.

Fritz started off by studying how the golden silk orb weaver spider in Panama composed and recycled its silk and managed to spin it into complex three-dimensional forms.

Researchers at the Group were able to apply these lessons to processes to manufacture silk tubes and filaments that could be used as conduits for nerve regeneration, medical sutures, and devices to regenerate damaged cartilage and bone tissues. They also showed how such materials could be used to replace titanium parts in products from razors to airplane parts.

Pauli argues that replacing current industrial processes with more biomimetic ones could help us reduce greenhouse gas emissions as well as shepherding the planet's scarce resources.

Fritz and his team have already made a number of contributions to turning such ideas into commercial realities with the founding of spin-out firms such as Orthox, Suturox, and Neurotex, all based on pioneering research at Oxford.

Fritz tells me that he hopes there could be many more benefits from the group's ongoing research which received a boost last year with an ERC Advanced Grant supporting his SABIP - Silk as Biomimetic Ideals for Polymers project.

Could spiders and silkworms really help to save the world? Watch this space...

In this guest post David Ferguson of Oxford University's Department of Earth Sciences writes about his research into volcanoes:

Earlier this summer I took an unexpected journey to the Afar Depression, a vast remote desert in the north of Ethiopia.

The Afar region is famed among adventure tourists for it’s sweltering temperatures, saline lakes and numerous (and often active) volcanoes. It was the latter of these that was responsible for my impromptu trip.

On the 28th June an instrument carried by a NASA satellite, designed to measure temperatures on the Earth’s surface, detected a new area of intense heat emissions whilst flying over Afar. The most likely cause of this thermal signature was an active lava flow, the product of a new volcanic eruption. As soon as we received this data we raced out to Ethiopia to try and catch the eruption in progress. You can read about our trip on The Guardian's Science Blog.

A week after our sudden departure we were back in the UK. The souvenirs from our unexpected trip: a box of fresh lava samples, visual and thermal images of a newly formed volcanic fissure and some slightly melted shoes (new lava flows require very sturdy footwear!).

Afar is the site of intense geological activity, a manifestation of the Earth’s crust being split apart by the movement of tectonic plates. The key to why so much of this geological activity is concentrated here is the presence of great volumes of magma beneath the surface. Periodically, a batch of this magma surges upwards from deep in the crust, splitting the ground apart as it forces its way upwards and, in some cases, reaching the surface and erupting out onto the desert floor.

During the past few years Afar has seen a marked increase in this magmatic activity and every so often we get the opportunity to try and collect some samples of the magma from new lava flows. By studying the chemical composition and physical characteristics of these, currently rare, eruptions we hope to learn about the magma reservoir beneath the surface and also whether we can expect more eruptions in the near future.

A problem in forecasting volcanic eruptions in this part of Afar is that this type of volcanism is not often seen on dry land. As tectonic plates are split apart they tend to sink down into the Earth’s mantle (much of Afar is currently below sea level) and as such the areas where this geological process occurs (called ‘rifting’) are typically found at the bottom of the oceans.

There is, however, one other region on Earth we can use as a comparison to Afar without the need for a submarine. That is Iceland, where the fracture zone that splits apart the oceanic crust beneath the Atlantic Ocean takes a brief detour onto land. In the late 1970s Iceland experienced, over a nine-year period, a series of events similar to those currently happening in Ethiopia.  Using the data we gathered on the size and duration of this recent eruption (and also a previous one in 2007) we can compare our data to the pattern of eruptions seen in Iceland during that time.

Similar to Afar, the Icelandic activity began with several pulses of magma forcing their way upwards into the shallow crust, which, despite causing earthquakes and ground fractures, did not make it all the way up to erupt at the surface. 

However, as the magma continued to surge upwards over several years more and more eruptions occurred, most of these lasting longer and erupting more lava than the previous one. By comparing the patterns of earthquakes and eruptions observed in Afar over the past few years with the Icelandic data we have forecast that there is a high likelihood that over the next ten or so years this part of Ethiopia will experience several more (and potential much larger) volcanic eruptions.

Our findings on this are currently being peer-reviewed for publication in an academic journal. In the meantime, however, we will continue to monitor this part of Afar and to catalogue and study future activity.

You can read more about this work on the Afar Consortium website.

David Ferguson is based at Oxford University's Department of Earth Sciences.

How can some sportsmen and women, in the heat of the moment, play on through pain that would floor anyone else?

Bert Trautmann, the Manchester City goalkeeper, famously played on through to the end of the 1956 FA Cup final - holding on for a 3-1 win - despite suffering a broken neck from a collision in the second half.

Similarly, why do some people seem to suffer long-lasting debilitating pain when others are better able to cope? Each of us individually can also experience pain differently at different times.

Pain of course is a subjective, variable and very personal experience that involves far more than a simple reaction to injury or damage. And although doctors can only rely on what each patient says about the pain that they’re experiencing, it is important to try and diagnose, monitor and manage that pain effectively.

Professor Irene Tracey’s group at the Oxford Centre for Functional Magnetic Resonance Imaging of the Brain has used brain imaging techniques for a number of years, aiming to provide an objective measure of individual experiences of pain.

By understanding how the brain processes the information coming from all the body’s senses as pain, they can begin to pick out differences between people.

Their latest results, reported this week in the journal PNAS, demonstrate that people’s personalities matter in their experience of pain. People that are more anxious, or worried about feeling pain, have differences in connectivity within their brains that make them more susceptible to actually feeling pain.

The team applied short laser pulses to the feet of 16 willing and healthy volunteers just at the point where they started to experience the pulses as being painful (‘you can ratchet up the laser pulses so you feel them as warm, then hot, then the point where you say “yeah, actually, that hurts now,”’ explains Irene.) These brief laser pulses were applied 120 times to each volunteer, and around half the time the volunteer would declare it was painful and half the time not - even though the pulse was exactly the same every time.

MRI brain scans during these experiments show that the volunteers’ brains were more active in pain-processing regions when they described the laser pulses as being painful - so this was a real experience and not down to any report bias or artefact.

But the researchers wanted to understand exactly what made one stimulus painful at one time while the very same stimulus at another time was fine.

‘We looked at the period just before the stimulus and asked “is there a difference in the way certain regions of the brain are connected or communicating before the stimulus is applied?”’ explains Irene. ‘The answer is that there is a striking difference.’

The researchers focused on the connection between ‘higher’ parts of the brain involved in the processing of pain, and part of the brain stem that can powerfully alter the experience of pain - turning its level up or down.

When there was good coupling between the two areas before a laser pulse, the volunteer felt no pain, and when the connectivity was poor, the pulse was experienced as painful.

Most interestingly of all, however, was that people that were more likely to be anxious or vigilant about pain (as scored on their answers to a questionnaire for these traits), showed poorer connectivity in general between these brain regions.

This difference in the hardwiring of the brain could account for how people with different personalities respond to pain, suggests Irene.

‘We now want to know whether we are born with this, or whether the brain becomes wired like this as it develops,’ she says. ‘It’s a chicken and the egg situation. We only have a snapshot in time with this experiment. We can’t tell what comes first.’