Serpentinites are rocks that contain a significant proportion of serpentines, which form by hydrothermal alteration of basic silicates (e.g., olivine). These rocks form primarily in the upper oceanic crust, due to hydrothermal circulation of oceanic water along the mid-oceanic ridges where new oceanic crust is generated. As a consequence, the oceanic crust that enters subduction zones is thought to be serpentinised extensively, at least in its upper part. The presence of serpentinite near the subduction interface is expected to have a key influence on subduction zone dynamics, because serpentine minerals have peculiar mechanical and physical properties: they are very weak compared to other crustal and mantle rocks, and they dehydrate (i.e., undergo chemical transformations and release free water) upon heating. The latter effect has dramatic consequences on the effective stress state in the subducting slab, and is thought to play a fundamental role in the generation of slow slip events, intermediate-depth earthquakes, arc volcanism, and water recycling in the mantle. The exact role of serpentinites in subduction processes is however difficult to quantify precisely since the exact location and amount of serpentine minerals in subduction zones remains poorly known. In order to test whether serpentinites are indeed responsible for the aforementioned features of subduction zones, it is of primary importance to be able to demonstrate their presence or absence at depth. Seismic imaging is the most robust observational constraint available, but the precise identification of serpentinites using seismic methods is difficult. Significant progress has been achieved in the determination of the elastic properties and seismic speeds of serpentine (antigorite, lizardite) single crystals. However, the deformation and dehydration of serpentinites has been shown to systematically induce significant cracking. The microcracks generated by deformation and dehydration may well remain open at depth in subduction zones, at least temporarily, due to the elevated fluid pressures arising from dehydration itself and buoyancy-driven fluid migration. Microcracking can potentially have strong, first order effects on seismic properties and anisotropy, but remains poorly quantified in serpentinites. In this project we propose to dramatically improve our ability to link seismic observables to the presence of serpentinite by (1) experimentally measure the seismic properties of serpentinites during deformation and dehydration, (2) quantify the microstructural evolution and the relationships between microcrack orientation and crystallographic preferred orientation, and (3) model the effects of microcracks on seismic wave speeds using effective medium approaches. Our study is expected to provide a robust characterisation of the seismic signature of deformed and dehydrating serpentinites, and thus have a direct impact on the interpretation of seismic images. In addition, our data will contribute to a better understanding of the deformation and dehydration mechanisms that are key aspects of subduction zone dynamics.

Finding ways to deliver high-quality health care to low-income populations in developing countries is a critical policy challenge. Our initial ESRC-funded project found that reducing user fees (by providing primary health care for free) does substantially increase Malian households' use of this care. However, we also find evidence that much of this care may be unnecessary or mis-targeted: our data suggest that children seeking care in government-run community clinics (CSCOMs) are frequently prescribed antimalarials and antibiotics when they do not need the treatment. This is particularly striking for malaria, since the Malian government has mandated that malaria diagnoses be confirmed by diagnostic testing. Our findings are consistent with a large body of economic literature, which on the one hand provides theoretical underpinnings for the problem of over-prescription and over-treatment, and on the other documents low levels of doctor effort and quality of care in both the public and private sectors across the developing world. Our implementing partner, Mali Health, has indicated that the increase in program costs due to over-prescription and the need for close monitoring and quality checks are a key barrier to scaling up the free-care intervention. We propose to conduct a follow-on project to identify the leading causes behind over-treatment, and test whether alternative incentive regimes can improve care outcomes without producing unnecessary costs. Our analytical framework is motivated by economic models of an "informed expert" selling "a credence good": the doctor has knowledge about the patient's illness and need for treatment that is not verifiable, and the patient must buy the treatment without knowing if it is truly what he or she needs. The model clarifies how doctor incentives, patient incentives, observability of diagnostic test results, and beliefs about test accuracy interact to produce care outcomes in this context. This analysis informs the design of a randomized controlled trial (RCT), which we will use to empirically test the model (as well as alternative theories for over-treatment) and identify promising strategies for improving care outcomes in the Malian public sector. Our primary application will be malaria, since high-quality, low-cost rapid diagnostic tests for the disease are readily available. However, given the striking rates of antibiotic use in our data, we also propose to use part of the new grant to conduct additional scoping work and expand the project to include bacterial illness if possible. The RCT will be conducted at 48 CSCOMs in the Bamako area and will allow us to evaluate the relative importance of test verifiability, provider beliefs about diagnostic test accuracy, and patient education about testing; provider incentives to diagnose and adhere to test results; and patient incentives to follow doctor advice and purchase medications. Over the course of the RCT we will construct a unique dataset that captures detailed information about patient demographic characteristics, symptoms, and treatment outcomes (tests and prescriptions given, medications purchased). We will also conduct home-based follow-up surveys to obtain information about patients' true malaria status, compliance with treatment, and provider satisfaction. This will allow us to estimate how alternative incentive and information regimes impact over-treatment and care outcomes in the public sector. We propose to forge a close collaboration with Malian health officials, to ensure that our project has maximal policy impact. Aside from its immediate relevance for the Malian public health system, this project will be of broad interest to researchers and policymakers working in the fields of economic development and public health.

Light triggers many important chemical reactions. These include photosynthesis, which converts sunlight to chemical energy and powers most life on earth, human vision, where light is detected using the light-induced isomerisation of a molecule in our retinas, and new technologies such as photodynamic therapies for cancer, photocatalysis, molecular photonics, photovoltaics, and organic light-emitting diodes in displays. Ultrafast imaging experiments that study these types of processes rely on computational modelling to interpret and analyse data and extract chemical and physical insight from the observations. Yet, the computational modelling remains very challenging, in essence because the photon ('light-particle') absorbed by a molecule in a photochemical process carries a large amount of energy, which forces the electrons and nuclei into complex coupled motion described by quantum mechanics, making computations exponentially more difficult than the corresponding system described by classical mechanics. The necessary calculations are composed of two different types of computations, which both require great technical expertise: electronic structure calculations and quantum dynamics. We will combine our expertise in electronic structure calculations and quantum dynamics, to create powerful new simulation methods. The team includes two world-leading experimentalists who are each expert in a complementary ultrafast imaging technique. As a team, we will push experiments and theory to achieve greater insight into complex light-activated dynamics in molecules. The project will provide a framework for interpreting multiple complementary state-of-the-art experiments. The long-term goal is to achieve simulations that are sufficiently powerful that we can use computers to design new photoactive molecules for new light-driven technologies. In the later stages of the project, we will tackle complex molecular systems well beyond the current cutting-edge of simulations, which will include exciting applications such as photosensitizers, photostabilizers, photoactive pro-drugs, photovoltaics, photocatalysts, and light-emitting diodes.

The most fundamental task in information security is to establish what we mean by saying that information is secure: what is it that we are trying to achieve? One subfield of information security that takes great care in tending to its definitions is cryptography. Indeed, finding the correct security definition for a cryptographic primitive or protocol is a critical part of cryptographic work. However, these security notions -- and everything that depends on them -- do not exist in a vacuum. While the immediate objects of cryptography are not social relations, it presumes and models them. This fact is readily acknowledged in the introductions of cryptographic works where authors illustrate the utility of their proposed constructions by reference to some social situation where several parties have conflicting ends but a need or desire to interact. Yet, this part of the definitional work has not received the same rigour from the cryptographic community as complexity-theoretic and mathematical questions. The broader social sciences offer a wealth of approaches to answering questions about social situations, relations, (collective) needs, imaginations and desires. However, they are often relegated to a service role in information security, e.g. to perform usability testing of existing security technologies after those have been designed. In contrast, in this project we ask social science to establish core notions for technology. To establish what security means within social settings -- to identify and understand security concerns -- one approach stands out in promising deep and detailed insights: ethnography. Ethnography is uniquely placed to "unearth what the group (under study) takes for granted". A key challenge in engaging those who depend on security technology is that they are not trained information security professionals. They do not know and, indeed, should not need to know, for example, that confidentiality requires integrity, that existing onboarding practices can be phrased in the language of information security, which different security notions cannot be achieved simultaneously and what guarantees, say, cryptography, can give if asked. Therefore, to know exactly what is taken for granted, or put otherwise, expected or desired, in social interactions, social and technical protocols and, indeed, cryptography is of critical import. Some more commonly relied upon social science methods in information security, while much more practical and less time consuming than ethnography, are therefore less suitable research approaches in this context. For example, questionnaires and surveys, both the qualitative and quantitative kind, are limited means of inquiry here. While interviews provide some opportunity for deeper engagement, ethnography allows us to learn that which people do not know themselves. Through close observations and analysis of everyday activities and relations, ethnography reveals "the knowledge and meaning structures that provide the blueprint for social action" within the group under study. The exploratory nature of ethnographic inquiry, rooted in fieldwork with the group it aims to understand, is thus a key enabler in unlocking an understanding of individual and collective security needs and practices. The inherently reflexive and embedded nature of ethnography enables such insights. In this project we adopt this approach to the specific example settings of large-scale protests. These, on the one hand, offer rich and diverse settings where security needs are paramount, while also being sufficiently different from standard cryptographic use-cases (e.g. in e-commerce) to promise novel insights. Based on our ethnographic findings, we will study existing technologies on whether they satisfy the security needs identified and will design novel cryptographic notions and solutions to satisfy these identified needs.

By taking advantage of their rarity and chemical inertness, geologists use the noble gases (helium, neon, argon, krypton, xenon) as tracers for the processes responsible for the evolution of the mantle. Noble gases can help answer questions about the amount and source of volatiles such as water in the mantle and how these have changed over time. For example a recent study from Japan showed that rocks from the mantle contain a noble gas signature similar to that of the oceans, suggesting that noble gases may be transported from the Earth's surface into the mantle in zones where tectonic plates collide. But which minerals are responsible for transporting the noble gases into the mantle and how much gas can these minerals transport? This proposal aims to quantify the amount of argon that a common crustal mineral, muscovite, can transport. Noble gases are also used to measure the rates and time scales of geological processes since radioactive decay of uranium produces helium, and decay of potassium produces argon. In particular, geochronologists use the decay of potassium to argon in muscovite to determine the timing and rate of mountain uplift and erosion. In plate collision zones, crustal rocks buried to depths of 100km or more are known to have been exposed on the surface within a few million years of reaching their maximum burial depth. As these vertical speeds are similar to horizontal plate tectonic speeds, geologists want to understand more about how rocks move and interact within these zones. In some minerals, however, and specifically ones commonly found associated with these deeply buried rocks, there is "extra argon" which makes the K-Ar (or, more usually, the Ar/Ar) age appear artificially old. We aim to show that this complication for geochronologists may actually be a help to mantle geologists by providing a way to transport argon from the crust into the mantle. One of the main aims of this project is to measure how much argon can become trapped in muscovite, and to determine whether the solubility changes with pressure and crystal "type" of muscovite. To do this we will grow muscovite in an argon-rich fluid in high pressure experiments at University College London. The resulting crystals will be analysed for incorporated argon in the Open University's high-precision Ar/Ar and Noble Gas Laboratory. Initial experiments will be used to test whether we can grow suitably large and pure muscovite. Subsequent experiments will test the effect of pressure and crystal type on how much argon is trapped during crystallisation. This project will produce results which have major implications for measuring geological time in rapidly buried and uplifted crust, and for our understanding of how and how quickly noble gases may be recycled from the Earth's surface into the deep mantle.