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Images of the brain with various areas ‘lighting up’ in a rainbow of colours are now pretty familiar to many of us.

These come from studies in which people are given tasks to do inside MRI scanners, and the areas that light up show where there is increased brain activity as a result. And ‘functional’ MRI [fMRI] has been incredibly successful in revealing the way the brain is organised.

But this approach of mapping tasks onto different areas of the brain is always going to be constrained by the experiment design and the task set, prior assumptions about what you hope to test for, and what you set out to see.

This is the reason why researchers are now looking to a new technique called resting-state fMRI, which gets rid of any of the constraints or assumptions of task-based fMRI.

Resting-state fMRI is just as it sounds. People are asked to do precisely nothing in the scanner - just rest for 5 minutes or so. Yet the results consistently and reliably show connections between areas of the brain that are working together in networks. The result is a map of the functioning brain.

Oxford researchers at the Centre for Functional Magnetic Resonance Imaging of the Brain (FMRIB) have been at the forefront of these efforts. They are co-authors on a new paper in PNAS by an international group of researchers that sets out the potential of the technique.

Dr Steve Smith explains: ‘If you’re interested in a specific group of people or patients - say with Alzheimer’s for example - you want to find any differences in brain activity that might be of interest, not just those involved in a specific task. With resting-state fMRI, you don’t necessarily have to know what you’re looking for.’

The group at FMRIB, led by Dr Clare Mackay and Steve Smith, has already shown the value of the technique. Last year they found differences in young people’s brain activity using resting-state fMRI according to whether or not they had a gene variant that is linked to increased risk of Alzheimer’s. This difference in brain activity is decades before any symptoms of the disease would be apparent.

Clare said at the time: ‘We have shown that brain activity is different in people with this version of the gene decades before any memory problems might develop. We’ve also shown that this form of fMRI, where people just lie in the scanner doing nothing, is sensitive enough to pick up these changes. These are exciting first steps towards a tantalising prospect: a simple test that will be able to distinguish who will go on to develop Alzheimer’s.’

As well as the potential clinical relevance of this form of brain scanning, the hope is that resting-state fMRI could connect differences in people’s brain activity with factors like age, sex, genes, behaviour, or disease progression.

Another great advantage of resting-state fMRI is that everyone will be conducting their experiments in the same way. This means that data can be combined from groups all over the world to map out the functioning networks in the brain - essentially giving the complete wiring diagram of the brain.

This is what the new paper by the international collaboration set out in PNAS this week. They show how it is possible to combine data from over 1000 volunteers collected at 35 different centres across the world (including Oxford). With all the data, they show they find the same patterns of networks functioning in the brain and are able to begin to see differences between different groups of people by age and by sex.

The PNAS paper compares this approach to genomics. Indeed, the maps produced of connections in the brain are being called the ‘connectome’ in the same way that the genome is the map of all our genes.

Steve Smith does see the analogy with genomics, suggesting that mapping out the connections which determine how our brains work is similar in concept to decoding our genes to discover how our body works. And there is also the similarity in approach - big international consortiums gathering data to pinpoint variation between people to gain more understanding about disease.

However, he points out that the resolution of MRI still needs to be improved. With genomics, everyone reads out directly the same fundamental chemical DNA sequence but, with MRI scans, there is still a distance between what is seen in MRI signals and the individual neural circuits that are active in the brain. 

It's great to see that Oxford's Dorothy Hodgkin is honoured in a new set of Royal Mail stamps celebrating the 350th anniversary of the Royal Society.

The stamp celebrates advances in X-ray crystallography she made at Oxford University: she determined the molecular structures of penicillin, vitamin B12, and insulin.

In 1964 she received the Nobel Prize for Chemistry, becoming the only British woman scientist to win a Nobel so far.

Royal Mail say the idea was to choose ten significant scientific RS figures from the last 350 years, with one figure representing each 35-year period. Each stamp includes a portrait and imagery relevant to the scientist's greatest achievement.

Hodgkin is the only woman in an illustrious line-up that includes Isaac Newton, Ernest Rutherford, and Edward Jenner. You can find out more about how the stamps were put together in this BBC Online audio slideshow.

For her undergraduate degree Hodgkin studied chemistry at Somerville College and, after doing doctoral studies at Cambridge, she returned to Oxford in 1934 as a fellow at Somerville and set up her X-ray equipment in a shared laboratory in a basement corner of the University Museum. She would continue her research and teaching work at Oxford for the next 43 years.

Her crystallography work enabled her to deduce the structure of ever-larger and more complex molecules. One of her greatest achievements was, with the help of one of the first electronic computers, solving the 100-atom structure of the vitamin B12 in 1957, a feat Lawrence Bragg likened to ‘breaking the sound barrier’.

Georgina Ferry, the author of the definitive biography of Hodgkin, writes: 'In the case of each of the three projects for which she is best known - penicillin, vitamin B12, and insulin - Dorothy pushed the boundaries of what was possible with the techniques available.'

'Her distinction lay not in developing new approaches, but in a remarkable ability to envisage possibilities in three-dimensional structures, grounded in a profound understanding of the underlying chemistry.'

'While she did not consider it part of her role to explore the function of the molecules she studied, her results made it possible for others to increase their understanding of their biosynthesis and chemical interactions, and hence to develop improved therapies for disease.'

In 1976 Hodgkin became the first woman to receive the Royal Society's most prestigious award, the Copley medal.

Special thanks: Oxford DNB

Using genetics to render female Aedes aegypti mosquitoes flightless could halt dengue fever in its tracks.

The finding is reported in a paper in this week's PNAS on work led by Luke Alphey of Oxford University's Department of Zoology and Oxford spin-out firm Oxitec.

We've previously reported on how the Oxford team investigated inserting a 'dominant lethal' gene into mosquitoes that, when passed on by males, would see the larvae die before they could develop and spread the disease.

As reported in BBC News Online and elsewhere the team's new approach targets females - whose bite is what actually passes on the infection that affects millions of people a year. Their work suggests that male mozzies can be genetically altered to carry a gene that limits wing growth in their female offspring - rendering their daughters flightless.

Not only does it stop these females from infecting humans but, as the researchers write in the paper: 'Flightless females also are effectively sterile, being unable to attract and mate males as courtship and mating depend on the wing oscillations 'song''.

Luke told BBC Online: 'The technology is completely species-specific, as the released males will mate only with females of the same species.'

'Another attractive feature of this method is that it's egalitarian - all people in the treated areas are equally protected, regardless of their wealth, power or education.'

The researchers believe their approach could be extended to other species of mosquito that spread human disease.

The research is reported in a paper, entitled 'Female-specific flightless phenotype for mosquito control', published online in PNAS this week.

In the world of fossils it's usually befanged predators or their feathered bird-like cousins that steal the limelight.

So finding out about Bonnericthys, one of the unsung heroes of the Jurassic & Cretaceous - as part of working on this news story - has been an unexpected treat.

These giants were about as far from the flesh-eating inhabitants of Jurassic Park as you can get: 9m-long fish gliding around the prehistoric seas hoovering up plankton much like the benign basking sharks, whale sharks and blue & grey whales we know today.

Big & small fry
Making the video turned up a lot of fascinating detail and context that didn't make the final cut: like the fact that these large filter-feeders shared the ancient oceans with the ancestors of smaller fry living off the same resources, such as early herrings and anchovies.

'These familiar fishes survive to the present day, but the most striking difference between these suspension feeders and the extinct ones we've studied is size,' Matt Friedman, of Oxford University's Department of Earth Sciences, told me.

'The extinct fishes reaching lengths of 9m or more are giants on any scale, but they are particularly massive in comparison to living bony fishes that thrive on plankton.'

The awkward size and shape of some of the museum specimens is one reason why they were misidentified or ignored, but another factor is the peculiar anatomy of the giant plankton-eater:

'First is the enormous mouth, with long, slender jaws that bear no teeth whatsoever - a feature common to filter feeders,' Matt explained.

'Another important feature is the enormous gill skeleton: Fishes use gills to breathe, but suspension feeders have co-opted their gill arches to extract plankton from the water. They pull off this trick helped by structures called gill rakers, finger-like projections that extend off the front of the gill arches, which can assume elaborate shapes in suspension feeders.'

'As for the body of these animals, it would have been very streamlined, with a well-developed pair of fins just behind the head, and a massive, crescent-moon shaped fin at the back of the tail.'

Things fall apart
These specialised lightweight bodies, fine-tuned by evolution, contain skeletons with very little bone - so that they tend to fall apart after death, leaving only fragments of skull and flipper to sink to the ocean floor and be preserved.

It was a series of new finds from excavations around the world that helped unlock the story of Bonnericthys:

'The most important fossil specimens for our study came from rocks laid down in western Kansas near the end of the age of dinosaurs, about 80 million years ago. We've also got other pieces of this same fish from other parts of the US including New Jersey, South Dakota, Wyoming, and Alabama,' Matt told me.

'Other examples of this group of fishes that we report for the first time came from Kent and Dorset here in the UK, as well as from as far away as Japan.'

These giants proved to be quite the globe-trotters, but it is the longevity of their 100m-year-dynasty that marks them out as an evolutionary success story rather than just an interesting experiment, Matt comments:

'They cruised the oceans for at least 100 million years. To put this in context, that's longer than the giant baleen whales have been around, and longer than any of the groups of  massive filter-feeding sharks.'

'Another way to think about these fishes is by comparing them to mammals: mammals have been dominant on land for something like 65 million years, the time from the end of the age of dinosaurs up to today. I think we'd all agree that mammals are a pretty successful group.'

'Of course these giant fishes never achieved the diversity of mammals, but they were in the oceans for a longer period of time than mammals have been the dominant land vertebrates.'

If you've ever been frustrated by wanting to take video and hi-res photos at the same time on your camera, you're not alone.

Physiologists from Oxford University faced just such a problem when they were trying to record what happened to heart tissue cells in their lab. Their homemade solution proved so useful that they are now working with Oxford University Innovation to turn it into a commercially-viable technology.

As Colin Barras reports in New Scientist the two Oxford researcher, Gil Bub and Peter Kohl, rebuilt a standard video camera to incorporate the digital chip from a home cinema projector - a chip that's studded with lots of tiny moving mirrors.

By fixing the chip between the camera lens and its image sensor they used the chip's mirrors as 'shutters' to slice the video into 16 lower-resolution frames: squeezing 400 frames per second out of the camera's standard 25 frames per second set-up.

Even better, as each set of 16 sequential frames come from different pixels on the same sensor, they can be combined to give hi-res images like a stills camera (see the image below).

'What's new about this is that the picture and video are captured at the same time on the same sensor,' Gil told me. 'This is done by allowing the camera's pixels to act as if they were part of tens, or even hundreds of individual cameras taking pictures in rapid succession during a single normal exposure.'

'The trick is that the pattern of pixel exposures keeps the high resolution content of the overall image, which can then be used as-is, to form a regular high-res picture, or be decoded into a high-speed movie.'

The new system, which the team describe in this week's Nature Methods, is likely to cost a fraction of the current price of cameras with this combined capability and could transform everything from CCTV to sports photography. 

The project was funded by the Biotechnology and Biological Sciences Research Council and the British Heart Foundation.