Monday, 24 March 2014

The 24 Hour Inspire 2014

The 24 Hour Inspire will take place on the 27th and 28th of March 2014.

Back when I was a Ph.D. student during my first stint at the University of Sheffield I had the pleasure to share a department with Dr. Tim Richardson, a gregarious, outgoing and altruistic Reader in Physics with interests close to my own. We would share a friendly chat in the tea room and a joke or two about our shared recent discovery of running (jogging!) and how it was helping us get somewhat more into shape. I could tell Tim was a likeable and sociable man for myself, but it was really through others that I began to realise just how far reaching Tim's positive influence was: he was a mentor and even friend to countless undergraduates who raved about his teaching style, his lectures legendarily full of demonstrations and the admission that learning physics isn't always easy (or the admission even that lecturers had to learn things at all!). Tim was also a respected boss and colleague. A few of my good friends down the pub have passed through his research group at one time or another and give happy accounts of their time in 'Tim's lab'.

In my first post doc in Australia I got as far as offering to run experiments for Tim and we were discussing our preparations to get the samples shipped over and ready for action; but that was the last time I ever spoke to him.

While I was in Australia, Tim was diagnosed with cancer. Wishing to turn his illness into a positive message to help others, Tim along with his friends and colleagues set up a charity, Inspiration for Life. The rest of the story has been put in to words much better elsewhere, (on the Inspiration for Life website and blog, for example) so I will not attempt to do so in very much detail. Above all this, Tim began keeping a diary after his diagnosis in order to share his experiences, fears and hopes with others, before he sadly died on 5th February 2013, aged 48. His diary will soon be available through Inspiration for Life.

The charity decided that a fitting tribute to Tim would be to host an annual event in the form of a 24 Hour Lecture-a-thon, called the 24 Hour Inspire. The first event took place in 2013, and the second will take place this week (at the time of writing): from 5pm on Thursday 27th March to 5pm on Friday 28th March 2014. This exciting event sees speakers from across the University of Sheffield and beyond tackle a wide range of topics as diverse as poetry, music, physics, sperm, robots; perhaps more accurately, life, the universe and everything. The event will raise money for the Sheffield-based Weston Park Cancer Charity and Impact (

I am excited about the event, not least because I am privileged to be able to play a small part in this amazing effort. I have volunteered to play some music at various times, not to mention contributing delicious items for the bake sale that will also take place throughout! I would encourage anyone in the Sheffield area (or further afield) who would be interested in taking in some lectures, some music, all whilst helping raise money for a very good cause. The event is taking place in Firth Hall at the University of Sheffield and starts at 5pm on Thursday 27th March. Admission will be £1 for one lecture or £5 for all you can take!

For more information about Inspiration for Life, or to donate to support their work:

Tuesday, 18 March 2014

UK facilities: the big science of looking at small stuff

Somewhere in a field in Oxfordshire, there are, side-by-side, two very large scientific instruments. One is housed partly in buildings as large as aircraft hangars, and partly under large mounds of earth; it fires protons onto a huge metal target to produce neutrons and muons. This is ISIS. The other is housed within a ring, looking side-on like the landed saucer section of the starship Enterprise; this machine accelerates electrons, causing them to produce exceedingly bright electromagnetic radiation in the X-ray spectrum. This is Diamond, the UK's synchrotron. These machines are the engines chugging at the heart of research facilities; scientific communities built around central instruments, covering square miles of buildings, employing hundreds of people and providing a scientific 'laboratory-from-home' for thousands more scientists, engineers, technicians, students and collaborators.

ISIS from the air. Image credit: STFC.
Diamond and ISIS are examples of big science that live right here in the UK. Facilities like these and others overseas happen to have become the bread and butter of my own scientific work, but more about that later.

It's a sort of rule* that the smaller the thing you wish to see, the larger a machine you will require to see it: think of CERN, the vast underground ring straddling the borders of countries and accelerating its packets of particles to collide together with the energy of a double decker bus, and all to reveal the tiniest and most fundamental particles in the Universe. We are talking a little bit smaller in terms of facility size, and a little bit bigger in terms of the structures we are looking at. Still we are in impressive territory; the primary ISIS beam line is hundreds of metres long from accelerator to target (and then some, for each instrument), and it's fair to say that the typical length scales probed are measured in nanometres; that is multiples of 0.000000001 metres, or billionths of metres. To use the obligatory reference, that is 100,000 times smaller than the width of a human hair.

I often cite a major turning point in my career as a Ph.D. student as the first time I entered the guide hall of the first Target Station at ISIS. I stepped along the raised metal gangway into that vast edifice of science, crammed with equipment, cranes, and portakabins. Among the concrete shielding blocks was an electric hum and the mechanical breathing of countless fans and compressors. It was a truly inspiring experience - and although on that first visit I had no idea of the difficulties and challenges that lay ahead (the beam is switched on 24 hours a day, 7 days a week for most of the year), I nevertheless had the strong feeling that I had just entered into a new, and special, scientific world.

The experimental hall at Target Station 1, ISIS. Image credit: STFC.

On that first occasion, I was helping out with a neutron reflectivity experiment. Like the bands of colour visible when a thin slick of oil sits on top of the surface of water, seen for example by the side of a road on a rainy day, the reflection of neutrons from a surface is sensitive to extremely thin layers of material and can tell us accurate information about the thickness and the chemical composition of what is deposited there. In this case, we were studying polymer brush layers: single polymer chains tethered at one end to a silicon surface to create a brush-like layer rather like a carpet of seaweed waving about in the water, but only nanometres in height. Such layers have extremely low friction and so are good lubricating coatings; they also hinder proteins from sticking to surfaces and so help to prevent the fouling process which can lead the body to 'reject' foreign objects, and so polymer brushes have uses in medical applications.

In my current work on polymer nanocomposites, we have a material which consists mainly of our host polymer but with mixed with a small proportion of a 'nanofiller', or additive, to change its properties. In our case, our nanofiller is usually some form of graphene (the flat sheets of carbon that have commanded so many column inches since their relatively recent discovery in 2007). We know that the nanofiller is in the composite (it is now a different colour, for example), but how is it distributed? What shape and size are the lumps? What effect, if any, has the nanofiller had upon the polymer chains themselves? From these questions and other, macroscopic experiments, we aim to improve and tailor these materials for use in engineering applications. For my part, we use small-angle neutron scattering, another of the techniques commonly available at facilities such as ISIS (and many others across the world).

That is, we take a beam of neutrons and 'shoot' them at the sample. As they interact with the sample they are scattered, forming a reciprocal-space scattering pattern which we collect on a detector. From that pattern we are able to deduce the shapes and sizes of features in our sample. The inverted nature of scattering is apparent: small features scatter the neutrons through wide angles, and conversely, the larger the feature, the smaller the scattering angle. Thus, even though we are talking about the big science of small stuff, you need a big instrument tens of metres in length that can see very low angles, to look at the bigger end of the small spectrum - objects up to 300 nanometers and beyond! (The smaller the angle the bigger the object you can see - hence the existence of 'ultra-small angle neutron scattering' for even bigger stuff).

These two examples are just a tiny taste of the breadth of science that goes on at facilities like ISIS and Diamond. We are lucky and indeed privileged to have such facilities, and to be able to use their unique powers to dig down and explore the fundamental structures of materials and of life, since a large and growing part of our community is looking at biological systems, such as proteins, DNA and living cells.

An experiment at ISIS or a similar facility can mean a lot of different things to a lot of different people. To me, it usually means a hearty full English breakfast followed by long days and longer nights of measurement, experimentation and investigation: labours in the laboratory and trials on the beamline. Above all other things though, it usually means that unique feeling that you are doing something that you quite simply can't do anywhere else, and that is special every time.

For more information about ISIS click here, and to find out more about Diamond click here.

*Only sort of, because we have very huge telescopes and other instruments that look at very, very huge things that are very, very, very far away, and they are way outside of my knowledge, although well worth getting excited about.