Features

I've blogged before about the International Linear Collider (ILC), a 'quantum searchlight' needed to answer fundamental questions about the universe likely to be posed by results from the Large Hadron Collider (LHC).

Oxford is a key partner in the ILC and its involvement has been threatened by the STFC budget shortfall that has led to the withdrawal of UK funding.

It's nice to finally report some good news: the European Commission has given the green light for a 5m Euro contract to develop the technology and resources needed to construct the ILC.

We should care because, as the ILC website tells us, 'The ILC is our searchlight to illuminate the unknown. We know about some of the things we are looking for: dark matter, the Higgs boson, extra dimensions, and superparticles. And we know where to direct the searchlight to find them - and possibly discover things along the way that we didn't expect. Up until now, our searchlights have not reached far enough. By building the ILC we will have one that does.'

'The collaboration that has already been in place for many years has received a major boost,' commented Oxford's Brian Foster, European Regional Director for the ILC's Global Design Effort. 'With the funding from the European Commission we can secure a leading role for Europe in the technology development for this exciting new project.'

Let's hope Brian and his Oxford colleagues can keep the flag flying for UK particle physics.

Every so often the New York Times comes up with a firecracker of a science piece: as evidenced by this NYT article by Tom Christopher on weeds and climate change.

It's like a written version of those nesting Russian dolls with many fascinating layers but one of the big headlines is: 'weeds benefit far more than crop plants from changes in CO2 and that the implications of this for agriculture and public health are grave.'

US Department of Agriculture researchers testing urban plots resembling the hot CO2-rich future conditions of many parts of the world discovered an 'ecology on amphetamines' with the city-weeds far out-stripping their country cousins.

In what's worse news for hay-fever sufferers plants such as ragweed produce twice as much pollen with more of the allergy-producing protein when exposed to higher levels of CO2.

Many weeds are already taking over (as the Kudzu-ridden field in Mississippi shown above demonstrates) as human activity accelerates climate change. So should we spray, burn and decimate our weedy friends?

Science yields another surprise: removing these interlopers doesn't bring back native plants, it causes the ecosystem to crash: suggesting that many weeds are 'passengers' simply exploiting new ecological niches opened up by climatic change rather than driving the extinction of native plants.

Instead, Chris suggests, we could learn from weeds which, after all, provided the original basis for all our crops: much as Oxford scientists are looking to do to create salt-tolerant wheat and other crops. Like our Neolithic forebears we need to seize the opportunity presented by changing conditions to breed new types of plants that benefit man.

In short it's the message evolution teaches plants and animals alike; adapt or die.

Could the problem of global warming be solved simply by making fossil fuels more expensive?

Writing in The Guardian Ashley Seagar reports that as the price of oil goes through the roof solar power is seen as increasingly attractive. This is especially so in Germany where feed-in tariffs oblige utilities to buy in renewable energy at above the market rate.

It poses some interesting questions about whether economic or technological efficiencies are actually slowing the spread of renewables. As I've mentioned before Oxford researchers are amongst those looking at how to improve energy generation from solar power.

Yet, whilst we can expect improvements in solar power (and other renewables), as was pointed out at a recent debate on energy at Oxford electricity is only part of the story. Over half of the energy we use is expended on heating space and water - something the electricity supplied by solar cells would be particularly ill-suited to.

Are we ready and willing to rip out all our gas boilers and replace them with inefficient electric heating? Can we afford the trillions needed to transform our energy infrastructure from a centralised model in which energy flows out to one in which a large portion is drawn in from here, there and everywhere?

There's another sting in the tale for people who say renewables are a 'magic bullet' for our energy woes. As the price of oil rises so nuclear energy, just like solar and wind, will start to seem more attractive too...

What makes galaxies stop producing stars? Contrary to what you might think galaxies don't just run out of star-forming gas, there has to be something that's dispersing the gas or there'd be many more stars in the sky.

Scientists believe two mechanisms play a role in 'quenching' star formation: exploding supernovae and Active Galactic Nuclei (AGNs) - the stormy centres of galaxies powered by supermassive black holes.

At a recent AAS meeting, Sugata Kaviraj of Oxford's Department of Physics presented the first observations showing the role of AGNs. What these observations show is that AGNs take over from exploding supernovae as the main mechanism by which gas is dispersed as galaxies reach the critical size of 10 billion times the mass of the Sun.

'Our models of galaxies are all based on the notion that Active Galactic Nuclei are involved in ‘snuffing out’ – quenching – star formation in galaxies which are too large for mechanisms based on supernovae to explain,' Sugata tells us.

'Astronomers believe that the jets produced by Active Galactic Nuclei are powerful enough to ‘blow away’ star-forming gas from even the largest galaxies but up until now we have not had the observations to back this up.'

'Our observations using ultraviolet light show, for the first time, the relationship between the mass of a galaxy and whether supernovae or Active Galactic Nuclei play a dominant role in quenching star formation.'

Quantifying the role that AGNs play in quenching is of prime importance to astronomers and astrophysicists as it would enable them to calibrate their models of galaxies.

The observations used in the study were of nearby galaxies, the challenge now is to widen the scope of the work to include a representative sample of galaxies.

If you’re as absent-minded as I am, then it may be of comfort that Oxford researchers have shed some light on how memory is encoded in the brain.

All the information we take in, store, and then recall is somehow held in a complicated net of connections between neurons in the brain.

‘We know a lot about the hardware the brain uses to store memories and information – the different types of cells and how they are connected,’ explains Ole Paulsen of the Department of Physiology, Anatomy and Genetics. ‘But we have very little insight into the software – the programs the brain uses and the way its code works.’

Memories appear to be written into patterns of activity across our complex neural networks. Some connections between nerve cells are strengthened while others are weakened. Confusingly, both strengthening and weakening require the same molecule to operate. ‘This had been quite a conundrum,’ Ole says. ‘How does one molecule lead to both behaviours?’

Ole Paulsen and Antonio Rodriguez-Moreno, now in Spain at the Universidad Pablo de Olavide in Seville, have now solved this memory puzzle. Their results are published in Nature Neuroscience.

The molecules that manage the strengthening and weakening of nerve connections are called NMDA receptors. A connection between neurons works in only one way, so that there will be a ‘sender’ neuron and a ‘receiver’ neuron. Both have NMDA receptors but which receptors are active determines the result. If they are active on the receiver side, the connection will be strengthened and if they are active on the sender side, the connection will be weakened.

The researchers studied one specific type of connection in the brain, but they hope the solution to this particular puzzle will hold more widely.

‘If this is true more generally, then it is a fundamental result that will change the way we look at how memory is stored,” Ole says.