Features

Genetically modified male mosquitoes have been shown, for the first time, to mate successfully in the wild.

The experiment, carried out in the Cayman Islands and reported in Nature Biotechnology, shows that males, modified so that any offspring they father die before reproducing, could help to tackle outbreaks of dengue fever and other insect-borne diseases.

‘We were really surprised how well they did,’ Luke Alphey, a visiting professor at Oxford University and chief scientific officer of Oxford University spinout Oxitec, which developed the approach, told BBC News Online’s Jonathan Black.

‘For this method, you just need to get a reasonable proportion of the females to mate with GM males - you'll never get the males as competitive as the wild ones, but they don't have to be, they just have to be reasonably good.’

The GM modified male Aedes aegypti mosquitoes made up 16% of the male population of the trial area and fathered 10% of larvae – close to the mating success rate of wild males and evidence the technique could work outside the lab.

Aedes aegypti is a target because it carries dengue fever – afflicting an estimated 100 million people each year with some countries seeing ‘explosive’ outbreaks.

Luke explains that bednets offer no protection against dengue because the female mosquitoes carrying the virus bite during daytime.

‘We don't advocate [GM mosquitoes] as a 'magic bullet' that will solve all dengue in one go,’ he adds, ‘so the question is how it fits in as part of an integrated programme - and for dengue, it would be a huge component of an integrated programme.’

The next stage is to see if the release of a group of GM males can have a significant impact on the number of cases of dengue.

Luke Alphey is a visiting professor at Oxford University’s Department of Zoology.

Oxford University helped to fund the development of the approach through four awards from the Oxford University Challenge Seed Fund (UCSF). Oxitec was spun out of Oxford University by Isis Innovation in 2002.  

Many of them are in Earth’s neighbourhood, patrolling the space between Mars and Jupiter, but there’s a lot we don’t know about asteroids.

Now new observations from the VIRTIS instrument aboard the Rosetta spacecraft are revealing what the potato-shaped asteroid Lutetia is made of.

I asked Fred Taylor of Oxford University’s Department of Physics, one of the team reporting the new findings in this week’s Science, what makes Lutetia special and what this new research tells us about our rocky neighbours…

OxSciBlog: Why is Lutetia an interesting asteroid to study?
Fred Taylor: All of the asteroids are interesting, because there is such a variety of sizes, shapes, and compositions. If we want to understand them we must study a large selection, and so far we only have close-up data on a few.

Lutetia is particularly interesting because it is one of the largest, about 130 km along its longest axis (it is potato-shaped) and a thousand trillion tonnes in mass, discovered as long ago as 1852.

Before the Rosetta encounter, Lutetia was remarkable for having an infrared spectrum (the way in which it reflects sunlight and emits heat radiation at different wavelengths) that is different from most other asteroids. We wanted to find out why this is, using the VIRTIS spectrometer. 

OSB: What do the latest VIRTIS observations tell us?
FT: The composition of the surface of Lutetia turns out to be nearly the same everywhere, whereas most asteroids and meteorites have a variety of materials exposed in different places.

The reason, it turns out, is that Lutetia is covered all over with a thick layer of dry, dusty soil that covers the hard surface. We know there is a hard surface, although we can't see it, because the density of Lutetia is very high, so most of it has to be hard rock with a significant metal - we'd expect mostly iron, but also nickel etc - content.

There's no sign of hydrated minerals or organic material, both of which are often present in other asteroids and meteorites. This, and the thick ubiquitous regolith, is what makes the spectrum of Lutetia unusual. The closest match we have found is to the so-called E-type meteorites, which are very depleted in oxygen (so the iron is present as sulphides etc rather than the more common oxides, for example), but we may not be able to confirm this without samples from Lutetia.  

OSB: How do these results help us understand other asteroids/the asteroid belt?
FT: This was the largest asteroid yet studied close up, until the Dawn spacecraft arrived at Vesta recently (and will go on to the largest, Ceres). The big asteroids (larger than 100 km in diameter) are thought to be remnants of the primordial asteroidal distribution - this means they are not by-products of fragmentation events, and their physical properties were probably determined during the accretion epoch.

They may be the only large bodies we have studied that are relatively unmodified since the early days of solar system formation (but there are others, icy rather than rocky, in the Kuiper belt out beyond Neptune that we will visit some day). 

OSB: What important questions about Lutetia remain to be answered?
FT: The next logical step would be to land on the asteroid and drill into its interior to find out what minerals are actually present, in what properties, and how they are distributed throughout the body, especially with depth, so we can see how Lutetia was originally put together. This of course is a major undertaking that will be some time in coming!

Professor Fred Taylor is based at Oxford University's Department of Physics.

A scientific consortium engaged in research relevant to the discovery of new drugs has been given a big boost, with almost £31 million in new funding over four years. Two new drug companies have also joined the public-private partnership, showing the recognised importance of this work to the drug development process.

The Structural Genomics Consortium (SGC) is based at the University of Oxford and the University of Toronto, Canada. It was formed in 2004 and carries out research on human proteins relevant to disease, supported by funding from the public and private sector. It makes all of its findings available to the global research community without restriction.

Since it was launched, private funding to the SGC has increased greatly as pharma companies recognise what the consortium can offer. A majority of the new funding now comes from private sources.

‘Pharma is increasingly recognising that early drug discovery is too complex for each organisation alone, and this is a way of accessing academic and clinical expertise,’ says Chas Bountra, chief scientist for the Structural Genomics Consortium at the University of Oxford.

The new members of the SGC are Eli Lilly Canada and Pfizer Inc, who join fellow drug companies GlaxoSmithKline and Novartis. The four companies will also provide more than £5.7 million worth of in-kind contributions, primarily medicinal chemistry resources.

The other consortium funders include the Canadian Institutes for Health Research, the Ontario Ministry of Research and Innovation and the Wellcome Trust.

The SGC scientific programme for the next four years will see its core strength in determining the three-dimensional structures of key human proteins continue. Understanding the structure of proteins can help guide the discovery and design of new drugs that interact with the proteins. Since its inception, the SGC has contributed more than 1,300 high quality three-dimensional protein structures to the public domain. 

But the SGC will also broaden its work, following successful pilot projects in ‘epigenetics’. There is broad agreement that a better understanding of epigenetics – changes in the activity of genes that occur without any changes in the DNA sequence – may eventually yield new approaches to diagnosing and treating a number of important diseases.

The research will generate antibodies against proteins involved in epigenetic control, and identify chemical compounds that block the action of specific human proteins. These tools – protein structures, antibodies and chemical inhibitors – are important early steps that facilitate the drug discovery process, targeting proteins involved in disease processes.

About £13.5 million of the new funding will be coming to the SGC base at the University of Oxford. Research here will focus on generating novel chemical inhibitors for epigenetic proteins thought to be involved in cancer, inflammatory and neuropsychiatric diseases. These inhibitors could help determine how things like diet, injury, toxins and other environmental factors affect disease susceptibility and progression at a molecular level through epigenetics, explains Chas Bountra.

Importantly, all the tools will be provided openly to the research community worldwide, rather than being locked up within the walls of any one institution or company. Providing structural data and chemical reagents for free should speed the process of research and drug discovery and avoid any duplication of effort.

It is clear drug companies are increasingly buying into this idea. Indeed, Chas believes this model of an open public-private partnership seen in the SGC can be extended much further down the drug development process, taking novel drug candidates as far as the critical early-stage clinical trials where many stand or fall.

He has spoken about how pooling the resources of academics, public funders and private drug companies, and openly distributing results in the absence of any protected intellectual property, should play an increasing role in coming up with the new drugs we need in crucial areas like dementia.

Most drug candidates will still fail at this early stage but the approach stops repetition and reduces exposure of patients, says Chas Bountra. And with those new drugs that work, pharma can then do what it’s good at – finding the best molecule, developing it, and taking it to market.

Scientists around the world are working on the building blocks that could be linked up to create a useful quantum computer.

Single photons are at the heart of many of these schemes and, at first glance, seem like ideal information carriers: once encoded they are able to travel across galaxies and bend around suns without this information being lost. 

Yet the quality that makes them such safe information carriers – the fact that they interact only very weakly with their environment – is exactly what makes them difficult to work with. 

‘The problem comes when you want to create, manipulate or measure this information,’ Nathan Langford of Oxford University’s Department of Physics and the University of Vienna tells me. ‘Because a single photon doesn't interact much with atoms or other photons, it is very hard to do these things efficiently. And efficiency is the key to the whole idea of quantum computing.’

Nathan is part of a team that report in Nature a new way of getting round this problem: ‘The main goal of our approach, which we call coherent photon conversion, is to make photons talk to each other.’ 

In standard single-photon experiments a laser beam is shone into a nonlinear material. Very rarely (usually around once in every 1,000,000,000 interactions) this will cause a laser photon to split into two photons: this effectively turns the material into a random (probabilistic) photon generator. However, such randomness isn’t very helpful if you want photons to process information in a predictable manner.

So instead of a powerful laser beam the researchers examined what would happen if a single photon was shone into a nonlinear material. 

‘You might expect that putting in a single photon would make it even less likely to get two photons out at the other end, but in fact we found the opposite,’ Nathan explains.

‘With a single photon input, if you make it interact with the material strongly enough, we found that it should be possible to make the probability of one photon splitting into two rise to 100% - something that is impossible with a laser input.’ 

What was even more surprising was that, by carefully tailoring the type of input light, the same sort of interaction with this type of material could produce many of the other essential processes needed to build a photonic quantum computer: this includes creating entanglement between two photons, and converting a weak laser beam into good single photons. 

‘With our approach, it turns out that it should be possible to build a single device with four I/O ports (perhaps all on a single photonic chip) which can provide all of the building blocks required for efficient photonic quantum computing just by varying what type of light is sent into each port. This should make it much easier to build more complex designs.’

He points out that this technique isn’t limited to optical systems; it could also be used in superconducting microwave circuits and optomechanics – for example, preparing high quality phonon states in the vibrations coupling mirrors or dielectric membranes to light fields. 

At the moment the work is still in the early stages: the big question is whether the efficiencies the team predict could actually be achieved. 

‘So far we have focussed on a simple model of the nonlinear interaction to illustrate the basic ideas of the scheme, but now we need a more detailed model which incorporates other real-world effects, such as finite response times of the nonlinear medium and photon loss,’ Nathan tells me.

‘From a design perspective, we now need to identify what can be done to optimise the nonlinear coupling, both by improving the materials and engineering a better design.’ 

The big challenge, he says, is to move beyond eye-catching ‘proof-of-principle’ demonstrations of the elements required to build a quantum computer and build a device which can do something that cannot be achieved with a normal computer.

Nathan comments: ‘With photons, the biggest roadblock to achieving this is still the issue of efficiency: efficiency in creating and detecting photons, as well as in manipulating them. Hopefully our work can help provide a useful step in this direction.’ 

A new free app for Android phones launched today is giving people the chance to get closer to the world’s largest physics experiment.

People who download the 'LHSee' app will, for the first time, get live data from collisions at the Large Hadron Collider (LHC) sent direct to their mobile phone, as well as being able to find out more about how its instruments work and play a ‘Hunt the Higgs boson' game.

The app is the brainchild of Oxford University scientists and is supported by STFC: I asked one of its creators, Alan Barr from Oxford University’s Department of Physics, about squeezing the LHC onto a mobile:

OxSciBlog: Where did the idea for the LHSee app come from?
Alan Barr: For ages I’d been thinking that with the amazing capabilities on modern smart phones we really ought to be able to make a really great app - something that would allow everybody to access the LHC data. In fact I’d sounded out a few commercial companies who said they could do the job but I found that it would be expensive, and of course I’d have to teach their designers a lot of physics. So the idea was shelved.

Then, a few months later, I had one of those eureka moments that make Oxford so wonderful. I was having a cuppa in the physics common room, and happened to overhear a conversation from Chris Boddy, one of our very many bright Oxford physics graduate students. He was telling his friends that for fun he was writing some small test games for his Android phone. Well you just can’t let moments like that pass.

Within no time we’d put together a proposal, STFC had provided a small grant award, and Chris had a prototype app running on his own phone. 

OSB: What will the app enable users to do?
AB: We’ve squeezed in a bunch of cool features. If you want to learn about the science of the LHC, then you can play with the animated tutorials about the LHC and the ATLAS detector. Then you can stream videos to your phone about the construction of the detector, and its operation.

When you’ve become an expert, you can play the ‘Hunt the Higgs’, game, to test your skills. Personally, my favourite is being able to view collision events in 3D on my own phone. 

OSB: How close does it get you to real science at the LHC?
AB: This is the nice part. When we showed the app to our colleagues at CERN they loved it. They agreed that, for the very first time, we could make a live stream of actual honest-to-goodness genuine LHC events available to the public.

You can get them in real time, so you are seeing the results as they happen. Of course we can’t send you every collision – the LHC produces GigaBytes of data each second. But what you get is real, and you can see all the detail. Amazingly it’s even possible to pick out the individual proton-proton collisions.

OSB: Why is an app a good way to communicate LHC research?
AB: As of May 2011 there are well over 100 million activated Android devices out there. I kept coming back to this idea that as well as being phones these are really small pocket-sized computers with network connections and touch screens.

Focusing on these features, it seems completely natural to design an app to explain how we do our science, and the beauty of the physics we hope to uncover.

OSB: What do you hope users will take away from using the app?
AB: When the LHC was started, the news media used eye-catching images of the collisions to accompany their stories. It was an obvious thing to do because the pictures are so interesting, but it can be hard to get beneath the surface.

With the app you can understand what these strange shapes and lines actually mean - in terms of the individual particles detected. Our hope is that people can now appreciate the pictures and the science all the more - and perhaps even be a little inspired.

Dr Alan Barr is based at Oxford University’s Department of Physics.