Fullerenes are football-shaped cages of carbon atoms, for the discovery of which the British scientist Harry Kroto won the Nobel prize in 1996. Inside the cage is an empty space. Chemists and physicists have found many ingenious ways of trapping atoms or molecules inside the tiny fullerene cages. These encapsulated compounds are called endofullerenes. One of the most remarkable methods was pioneered by the Japanese scientists Komatsu and Murata, who are project partners in the current proposal. They performed molecular surgery . First, a series of chemical reactions was used to open a hole in the fullerene cages. A small molecule such as dihydrogen (H2) was then inserted into each fullerene cage by using high temperature and pressure. Finally, a further series of chemical reactions was used to sew the holes back up again. The result was the remarkable chemical compound called dihydrogen endofullerene. A new notation even had to be invented to write the formula down. The result of encapsulating H2 in a C60 fullerene molecule is denoted H2@C60. In this project we will perform magnetic resonance experiments on derivatives of H2@C60. Magnetic resonance is a method in which a sample is placed in a strong magnetic field and illuminated with radiowaves. The nuclei of the hydrogen atoms produce a radiowave response that may be analyzed to obtain detailed information about the molecules in the sample, where they are located, and how they are moving. The most familiar form of magnetic resonance is magnetic resonance imaging (MRI) which is used in hospitals to obtain anatomical pictures and diagnose medical conditions.In this project we will perform magnetic resonance on H2@C60 compounds and their highly-symmetric substituted derivatives, which have a number of useful properties such as water solubility. We will study the motion of the H2 molecules inside the nanoscale cages.In one of the subprojects we will synthesize and crystallize H2@C60 molecules in such a way that they are held in a highly symmetrical crystal. According to certain theories, the hydrogen molecules will behave in an unusual way under these conditions. The molecules themselves will emit magnetic resonance signals, not just the nuclei. We will try to observe this phenomenon for the first time on solid materials.The second subproject concerns a phenomenon called ortho/para conversion. Werner Heisenberg received the Nobel Prize in 1932 for predicting that ordinary hydrogen has two distinct forms, called ortho and parahydrogen. This was proved to be correct. The H2@C60 forms therefore come in two different types, some containing ortho hydrogen, and some containing parahydrogen. We will study in situ how these two forms interconvert with each other, and in particular, whether the ortho/para conversion may be induced by light.If the effects are observed as expected, some important consequences may follow. In particular, it should become possible to enhance the strength of certain NMR signals by a large factor (up to of almost 1 million) by irradiating the sample with a suitable laser beam. If this works it will have implications for a wide range of sciences, possibly including medical MRI. One of the aims of this project is to perform the preliminary work which will determine the feasibility of this novel NMR enhancement scheme.

The purpose of this project is to understand why new nerve cells are produced only in particular areas of the brain and why injuries cannot be repaired in other brain areas. Nerve cells are produced by special cells called stem cells that retain the properties of cells in the embryo to divide and produce various types of specialized cells. Stem cells are only found in limited areas of the brain where they divide throughout life to produce new nerve cells. We have found a protein called Ascl1 that stimulates the divisions of the stem cells and is therefore important for the production of new nerve cells. Our collaborators at the Karolinska Institute in Sweden have also found that the same protein Ascl1 is also present after a stroke in another brain region and in a distinct type of cells called glial cells. Some of these glial cells behave like stem cells when Ascl1 is present after stroke, as they divide and produce new nerve cells, but others do not react to the presence of Ascl1 and fail to produce nerve cells. To help the brain repair the damages caused by strokes, there is clearly a need to improve how glial cells react to the injury and to help them become more like stem cells. For this, we need to understand better how Ascl1 works. With this project, we want first to understand why Ascl1 is present in stem cells and in some glial cells after a stroke but not in others. We will therefore study the molecules that control in which brain cells Ascl1 is found. Second, we want to understand why, when Ascl1 is present in glial cells, some behave like stem cells and divide while other do not react to the presence of Ascl1 and continue to behave like normal glial cells. Ascl1 is a transcription factor, which means that it controls the activity of many genes in the cells where it is present, and these genes in turn control the behavior of the cells such as their divisions. We will therefore examine the genes that are controlled by Ascl1 in stem cell-like glial cells that respond to Ascl1 and we will find out why the same genes are not controlled by Ascl1 in other glial cells. We expect our research to lead to a better understanding of how the brain reacts to injuries such as strokes and why it has a limited ability to replace the nerve cells lost with new cells. In the longer term, we hope to have learned enough of the effect of stroke on glial cells to help devise treatments that convert more glial cells into stem cells and help the brain repair itself.

Abstracts are not currently available in GtR for all funded research. This is normally because the abstract was not required at the time of proposal submission, but may be because it included sensitive information such as personal details.

In the lower atmosphere ozone (O3) is an important anthropogenic greenhouse gas and is an air pollutant responsible for several billion euros in lost plant productivity each year. Surface O3 has doubled since 1850 due to chemical emissions from vehicles, industrial processes, and the burning of forests. While land ecosystems (primarily forests) are currently slowing down global warming by storing about a quarter of human-released carbon dioxide (CO2) emissions, this could be undermined by rising O3 concentrations impacting forest growth. This in turn would result in more CO2 left in the atmosphere adding to global climate change. Tropical rainforests are responsible for nearly half of global plant productivity and it is in these tropical regions that we are likely to see the greatest expansion of human populations this century. For example, Manaus, in the centre of the Amazon rainforest has seen a population boom in the last 25 years, with the number of residents doubling to just over 2 million people. Alongside this growing population, we see the expansion of O3 precursor emissions from urbanization and high-intensity agricultural areas. The global impacts of changing air pollution on tropical forests are potentially profound. In his seminal work in 2007, PI Sitch and colleagues at the Met Office and Centre for Ecology and Hydrology, were the first to identify the large potential risk to tropical forests from O3 pollution, and how that could in turn accelerate global warming. However, their study presented two major challenges for the research community: 1) the scale of this effect is highly uncertain; as their global modelling study was based on extrapolating plant O3 sensitivity data from temperate and boreal species. This project will address this by providing the first comprehensive set of measurements of O3 effects on plant functioning and growth in tropical trees. Also, as both O3, CO2 and H2O are exchanged between the atmosphere and leaves through a plants stoma, higher levels of CO2 provide plants the opportunity to reduce their stomatal opening, which in turn leads to reduced O3 uptake and damage. This project will for the first time investigate the potential synergistic or antagonistic impacts of climate change (CO2 and Temperature) on O3 responses in tropical forest species. 2) a fundamental challenge in all global vegetation modelling is to accurately represent the structure and function of highly biodiverse ecosystems; global models are generally only able to represent a limited set of generalized plant functional types (e.g. evergreen trees, C4-grasses etc). However, recent collection and synthesis of plant functional trait data (e.g. leaf nutrient concentrations, leaf size and shape) have enabled improved representation of ecology and plant function in global models. A group of scientists, including project partner Johan Uddling, have very recently proposed a unifying theory for O3 sensitivity in temperate and boreal tree species based upon leaf-functional traits. We are in a unique position to take this work forward to test the theory in tropical forest species, and to test the implications of this at the regional and global scale. The inclusion of the relationship between O3 sensitivity and basic plant functional traits in our global vegetation model, JULES (Joint UK Land Environmental Simulator), will lead to a step-change in our ability to assess the impact of air quality on tropical forest productivity and consequences for carbon sequestration. The model will be applied at O3 hotspot locations in tropical forests and together with observed plant trait information and O3 concentrations we will be able to extrapolate beyond the single plant functional type (PFT) paradigm. Global runs of JULES will also enable us to investigate the implications of future O3 concentrations, changes in land-use, and climate change scenarios on the tropical forest productivity and the global carbon sink.