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Food industry, environmental monitoring, healthcare, diagnostic and micro-fluidic applications often require understanding the rheology of small volumes of simple and complex fluids. Although most of the processes affecting viscosity and density of fluids occur at microscopic length scales, traditional rheometers only allow investigating fluid properties in the bulk, leaving a gap of several order of magnitudes in length between what can be measured and what causes the observed changes in physical fluid properties. MEMS (Micro-Electro-Mechanical Systems) represent a really promising way to fill this gap, thanks to their ability of probing extremely small volumes of fluids. Traditionally, MEMS structures are excited using an external signal and their resonance frequency is used to track changes in fluid properties. However, the dynamics of such systems in a viscous fluid is not trivial and not fully controllable yet, often resulting in poor measurement signal-to-noise ratio that ultimately translates to poor accuracy and reliability. The research proposed here aims to overcome this limitation of MEMS sensors, by creating a nonlinear self-excitation mechanism capable of automatically tracking the oscillation frequency of a microcantilever immersed in a viscous fluid. Changes in fluid properties translates to oscillations frequency shifts that can be easily tracked in real time without performing the frequency sweeps that are the main cause for poor accuracy in traditional externally excited MEMS sensors. This will allow for unprecedented resolution, ease of use and reliability of viscosity and density measurements on extremely small volumes of fluid.

The aim of the research is to develop a new rheological test that accurately detects the onset of clot lysis (de-Gel Point) and has the ability to assess and monitor patient response to the therapeutic break down of blood clots. We propose to show that the de-Gel Point is able to detect thrombolytic therapy in a pilot study involving a small cohort of stroke patients. Furthermore, we aim to determine whether a correlation between rheological parameters collected during analysis of the Gel Point and de-Gel Point can be related to clinical outcomes in patients diagnosed with acute ischemic stroke. The research area is Clinical Technologies.

In this project we will prove the principles of fabricating graphene in a form useful for manufacturing nanoscale electronics and fabricate some simple devices. Graphene is a form of carbon discovered in the 21st century: a single two dimensional sheet of atoms in a hexagonal chickenwire array. It completes the set of carbon materials, which already had zero-dimensional (buckyballs), one-dimensional (nanotubes), and three-dimensional (graphite) members that are all formed by rolling or stacking up graphene sheets. In its simplest form it can be made by anyone / a pencil trace consists of millions of carbon flakes, and amongst the millions a few will be just one atomic sheet thick. Experiments on these flakes have shown that they have really remarkable properties, particularly for electronic components. The two-dimensional nature of the material, along with the symmetry of the lattice, means that the electrons in the graphene sheet have the same dynamics as relativistic particles such neutrinos: they are now commonly referred to as massless Dirac fermions, with a new quantum number, chirality, not possessed by free electrons. This has been shown to lead to bizarre new physics such as finite electrical conductivity without charge carriers and new versions of the quantum Hall effect. Although new nanoelectronic devices based on this novel physics offer exciting possibilities, using graphene can also make marked improvements to present day technologies. This is because it possesses the higher value of a key materials property than any other semiconductor: the mobility. A simple field effect CMOS-like transistor, using a graphene flake to form the channel, outperformed Si by more than a factor of ten. A major obstacle to achieving this is that building complex circuits from randomly placed, shaped, and sized flakes is not possible using today's planar fabrication technologies where reproducibility is key. What is needed a uniform layer of graphene coating an entire wafer that can be patterned and processed in the usual way. The most promising way to do this currently seems to be to use SiC wafers used commercially in high power electronics. A proper surface treatment in ultrahigh vacuum preferentially removes silicon atoms, and the carbon atoms that remain reconstruct themselves to form graphene. The promise of wafer-scale device-grade material offers the possibility of not just forming transistor channels out of graphene, but carving entire circuits from a single graphene sheet. At Leeds we have been working on epitaxial graphene production now for roughly a year. We have set up and tested the various surface science instruments that will be needed to show that graphene has indeed formed on the surface of our SiC wafer. Our recent efforts have concentrated on achieving the very high temperatures for the wafer in UHV that are the key step of producing the surface graphene, and after a series of improvements we are now close to reaching those needed. Once we have graphene, we shall optimize its production and start to make electronic devices from it. In this proof-of-principle project we have two main aims: to develop a reliable protocol for forming graphene on SiC wafers in a form useful for scaling up to manufacturing; and to build some simple demonstrator devices to show that this material can be processed in nanoscale devices including gates that can control a switching action. We will also begin some pilot experiments on connecting magnetic electrodes to graphene devices, with a view to preparing the ground for future projects involving spintronics in graphene/using the electron spin as well as charge to store and process information/which is potentially a very fertile area, as quantum spin states are very long lived in graphene, even at room temperature.

[In what follows: 1. Reliability is the probability that failure will not occur; 2. A characteristic value is that single value of a material property which, when used in a deterministic analysis, will give the same response as a stochastic analysis for a given level of reliability; 3. A reduction factor is that factor (from 0.0 to 1.0) by which the mean property value is scaled to give the characteristic value.]The proposed research concentrates on the fact that natural materials are variable and that representation of this variability appears crucial to getting a realistic understanding of certain geotechnical and geo-environmental problems. A specific problem is chosen for illustrative purposes. The investigation requires one Research Associate, who will focus on: (a) converting existing finite element codes from serial to parallel environments; (b) using these optimised codes to investigate the influence of heterogeneity on 3-D slope stability. It involves a total cost of 91k plus notional service costs of 104k, and is divided into two parts:1. The stability of cut slopes in clay. This simple (total stress) application will determine reliability-based reduction factors for undrained shear strength, from which reliability-based characteristic values may be derived. Of particular interest will be the comparison between reduction factors based on 2-D and 3-D analyses: i.e. how conservative is the 2-D approach, and what economies are to be gained through basing reduction factors on the true 3-D response? The study will also investigate the influence of heterogeneity on the evolution of failure mechanisms and on the volumes of soil involved in potential slides.2. The stability of underwater sandfill slopes (using a coupled effective stress approach). The first stage will be to compare 2-D and 3-D responses for long slopes. (Hence, the remit will be similar to that for cut slopes in clay, except that the derived reduction factors will be for soil friction angle.) The second stage will consider the Nerlerk underwater berm. This structure was designed to form part of a bottom-founded oil exploration platform in the Canadian Beaufort Sea, but failed during construction (at a height of 26 m) due to static liquefaction. This complicated 3-D application will simulate the construction of the berm, and will result in predictions of the probability of failure, the height of the berm at which failure occurs, and the geometries and volumes of potential slides. (Note that there are detailed field measurements available for comparison.) Significantly, it will provide a benchmark against which previous, current and future 2-D investigations may be properly quantified.The proposed research will demonstrate a new and more meaningful approach to representing geo-structural response, with the definition of stability (reliability) now reflecting the variable nature of the material which is being analysed. Geo-environmental applications are seen as a particular area in which parallel stochastic analysis will flourish.

A combination of computer-aided drug design techniques and synthetic organic chemistry methods will be used to identify and synthesise novel broad-spectrum antiviral treatments, in the form of small-molecule compounds, for different viral infections, caused by coronaviruses, New World arenaviruses (NWA), and by enteroviruses. Coronaviruses are responsible for deadly human diseases such as SARS, MERS and COVID-19. The second viral group is instead associated with deadly haemorrhagic fever diseases in humans, while the third is responsible for numerous, severe conditions, especially in young children. In all cases, suitable targets for the development of broad-spectrum therapies have been identified. These targets will be studied with a series of in silico analyses, which will guide the design and synthesis of novel compounds, able to interfere with the essential functions of these proteins, and therefore to impair the virus life cycle.

Hair bleaching is a vital part of hair care industry. Unfortunately, the bleaches are strong oxidizing reagents, and apart from lightening the hair colour, cause some damage to the hair. The most successful recipes for hair bleaching work quite selectively, by causing minimum damage while providing the required lightening effect. However these recipes have been largely developed by the trial and error method, and the chemistry involved in the hair bleaching reactions is not well understood. The bleaching is likely to proceed via formation of free radical intermediates. This proposal aims to use EPR spectroscopy to unravel the mechanisms involved in hair bleaching and identify the main intermediates. Such mechanistic understanding of the chemistry involved in hair bleaching will help develop more selective, less damaging recipes in the future.

As modern robots become increasingly present in our workspaces, public spaces, and homes, we want to facilitate easier and more natural human-robot interaction and collaboration. One of the key challenges is to recognize the fact that users may be significantly diverse from one another. We therefore wish to explore how to recognize this diversity and enable robots to infer the capabilities and plans of their collaborator. By doing so, the robots can know what to expect from their collaborator and can plan to maximise their assistance, but also adapt online to benefit the collaborator and the interaction. The key research objectives are determining how we can leverage implicit physiological and social signals elicited by humans in an interaction and understand them as feedback for the robot to act upon. We want to incorporate this feedback into an adaptive framework, by which the robot learns to adapt and tailor its policies to the user. Furthermore, we want to infer the person's capabilities from observations, and reason about them when computing plans for shared tasks. We want to implement these frameworks in collaborative tasks such as block stacking and a gamified cooking task. To achieve these objectives, I will first conduct a study linking human signals to mental states in a human-robot interaction scenario, investigating whether signals such as eye gaze provide information about the human's mental state. Then, I will take the findings from the study and incorporate the signals as feedback signals in a learning agent who is trying to optimize its behaviour and tailor it to its collaborator. Lastly, I will develop a learning algorithm that will observe a person's trajectories and construct an underlying symbolic model which explains the observed trajectories and use this model to plan its actions in an interaction, complementing those of the human. The expected novel contributions are three frameworks: a framework that uses signals from the human to adapt robot's behaviour in a human-robot interaction, a framework which builds human models that explain observed behaviours and is then able to reason about the human's capabilities, and lastly, a framework unifying these two elements in a single unified reasoning system which is able to adapt online, but also reason about the collaborator during planning of the robot's actions. This PhD is relevant to the following EPSRC research area is Artificial Intelligence and Robotics.

The 'Physics of Life' is a current Grand Challenge research theme for EPSRC. It is a very fruitful interdisciplinary research field, and a strategic investment for the UK because of the potential our research base has to make leading contributions at or beyond the best efforts in the EU, USA and China, even though we lag behind these somewhat in investment. The strategic imperative arises from (i) the new techniques in experiment, theory and modelling from soft matter physics, instrumentation (especially imaging) and computational physics (including large data processing), together with (ii) a rich field of biological challenges that require physical methods to address at many length scales of biological systems from the molecular to population levels. This is even more true now than at the start of the first Network. Examples of (i) are: advanced AFM of membranes, high-resolution and 3D methods in optical microscopy, high-performance computing of complex molecular matter, the subfield of 'protein physics', field-theories of phase separation, coarse-graining in macromolecular matter, active soft matter, non-equilibrium thermodynamics. Examples of (ii) are: tissue growth and form, cell differentiation, cellular environment sensing, cell membrane rafts, evolutionary dynamics, fibrillar self-assembly, molecular motors.

The Crystal Sponge approach soaks an uncrystallisable compound eg an oil, into a porous crystal - the combined crystal structure of the host and 'uncrystallisable' guest can then be determined. This approach has been adopted by the pharmaceutical industry but not taken up in academia. This PhD will explore the feasibility of applying this approach to entirely new areas of research that otherwise would not have considered the use of crystallography. The studentship sits in the middle of an industry-academia project (Merck & Rigaku with UoS) to explore he academic applicability of the technique, an EPSRC Impact Acceleration Account project to engage new user communities and the establishment of this technique as part of the National Crystallography Service offering. The studentship will firstly explore new application areas for the technique with the commercially available crystal sponge. This will begin through collaboration with UoS research groups in molecular machines and supramolecular chemistry (Goldup) and organic synthesis (Linclau, Harrowven, Brown & Whitby) and ultimately spread further in the chemistry department (Chemical Biology section) and wider than UoS through these group contacts. The studentship will go on to investigate purity requirements for the technique and develop a methodology and protocol for routinely preparing an 'as provided' sample for soaking into a sponge. Having acquired a library of crystal sponge structures, the truly ambitious aspect of the project will look at energy calculations to understand interaction between host and guest so that mechanisms of adsorption can be postulated and new sponges designed.

The discovery of new materials with outstanding properties motivates much of modern chemistry, physics and materials science. Electronic and magnetic materials e.g. superconductors, magnetoresistors, ferroics and multiferroics are a particular challenge due to the unpredictability of the ground states of correlated electron systems, and their frequent sensitivity to small changes in chemical composition and physical conditions. Such inorganic materials tend to have dense, strongly-bonded structures, and so high pressures and temperatures are needed to change their chemical structures and properties. We propose to use pressures up to 25 GPa (250,000 bar) to synthesise new superconductors and other electronic materials:1. A breakthrough in high temperature superconductivity has recently occurred with the discovery that doped rare earth oxypnictides RFeAsO can show critical temperatures surpassed only by the high-Tc cuprates. These materials are clearly the 'next big thing' in superconductivity and will dominate the field over the coming years. We have already demonstrated the utility of our high pressure approach by preparing new superconductors (TbFeAs(O,F), TbFeAsO1-x, DyFeAs(O,F)) with Tc's up to 50 K at high pressure. We propose an investigation of further new RFeAs(O,F) and oxygen-deficient RFeAsO1-x superconductors up to the end of the rare earth series, growth of RFeAs(O,F) crystals, exploration of other chemical substitutions to induce superconductivity, and studies of other families of RMXO and related AM2X2 materials that offer further possibilities of finding new superconductors. 2. Perovskite type transition metal oxides with orbitally-degenerate electronic configurations have many outstanding properties, most famously superconductivity in Cu2+ oxides and CMR colossal magnetoresistances) in Mn3+ oxides. Many new or uncharacterised perovskites can be made at high pressures. We will investigate MnVO3, which unusually has magnetic 3d metals at the A and B sites, possible non-Fermi liquid behaviour in SrIrO3, and the intriguing phase LaRuO3, apparently containing the Ru3+ state which is very rare in oxides.3. New transition metal oxynitrides such as RZrO2N will be investigated - these may show CMR when lightly doped, and magnetic and ferroelectric orders (multiferroism) from R (rare earth) moments and off-centre Zr displacements. We will also explore general new routes for making metal oxynitrides by reacting oxyhalides with Li3N under pressure.4. Bismuth transition metal oxide perovskites e.g. BiMnO3 are important multiferroics - we will explore possible Ruddlesden Popper analogue phases Bi3M2O7 and Bi2MO4 which may be accessible at very high pressures (12-25 GPa). The high pressure form of Bi2CuO4 will also be important for superconductivity.A 1000 tonne press and Walker type synthesis module have recently been set up in Edinburgh as part of the Centre for Science at Extreme Conditions. We will extend the methodology by designing and manufacturing a new sample configuration for very high pressures (up to 25 GPa) and developing crystal growth protocols guided by in situ experiments at ESRF.The structures of the above materials will be determined by X-ray and neutron diffraction, including magnetic neutron scattering to determine potentially unconventional spin structures of RFeAsO for late R elements with large dipolar and quadrupolar moments. Electronic transport and magnetic properties will be measured in CSEC, and further properties will be explored through UK and international collaborations.A 4 year project is needed to allow all of the research to be undertaken by a PDRA (Dr. Rodgers) and by a PhD student who will focus on the new superconductors. Technical and consumables support are also requested to enable a productive high pressure synthesis programme.