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RAS

Russian Academy of Sciences
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19 Projects, page 1 of 4
  • Funder: UK Research and Innovation Project Code: EP/V055593/1
    Funder Contribution: 930,843 GBP

    Nuclear magnetic resonance (NMR) is one of the most versatile forms of spectroscopy in the physical sciences, with applications spanning the full range from fundamental physics, quantum theory, chemistry, materials science and biochemistry to structural biology and clinical applications (especially in the form of magnetic resonance imaging, MRI). In most cases, NMR spectroscopy employs the strongest possible magnetic field, since this usually generates the strongest signals with high resolution of the different chemical sites of the atomic nuclei. Nevertheless, there are circumstances in which it is desirable to perform NMR over a range of magnetic fields, including the ultralow field regime, in which magnetic shielding is used to achieve very small magnetic fields over three orders of magnitude smaller than the earth's magnetic field. NMR in this ultralow field regime is very special in several ways. Firstly, the information content of the NMR spectrum is determined not by chemical shifts but by spin-spin couplings. Secondly, the line width in this regime is not governed by the magnetic field inhomogeneity, as in ordinary NMR, but by dissipation effects (relaxation). Extremely narrow linewidths (millihertz) are often achieved. Thirdly, the different species of nuclear spins are tightly coupled in the ultralow magnetic field regime, giving rise to the special phenomena such as heteronuclear long-lived states, which do not exist in larger magnetic fields. Fourthly, optical magnetometry techniques may be used to detect the magnetism of the nuclear spins, as opposed to electromagnetic induction, which is used in conventional NMR. The zero-to-ultralow field (ZULF) regime therefore offers a special form of NMR which has a quite different nature to ordinary NMR spectroscopy, and whose features and possibilities are only just starting to be explored. There is currently no equipment in the UK which allows observation of NMR signals in the ultralow magnetic field regime. The proposed research involves the construction of a device which shuttles a sample in a rapid and highly controlled way between the high-field region of an ordinary NMR magnet and a magnetically shielded chamber, equipped with optical magnetometers for the detection of the NMR signal in the ZULF regime. This equipment will allow us to explore the spin dynamics in the ZULF regime with great precision and also exploit the ZULF regime as part of a high-field NMR procedure. This allows numerous multidimensional NMR experiments in which the advantages of both regimes may be combined. In addition the equipment allows the possibility to explore NMR relaxation over a very wide range of magnetic fields, allowing the probing of molecular motion over an extremely wide range of timescales. In addition the equipment will permit the development of advanced methodology for manipulating nuclear spin systems in the ZULF regime, such as the development of "ZULF decoupling" sequences which cause the system to behave as if spin-spin couplings between nuclei of different isotopic types are suppressed. This will make the ZULF NMR signals narrower, more informative, and easier to interpret. The proposed equipment will be world-unique and will be made available to the UK scientific community as a research facility. A workshop and training course will be provided during the final stages of the research project in order to facilitate the transfer of knowledge on this special form of NMR to UK scientists.

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  • Funder: UK Research and Innovation Project Code: NE/S008276/1
    Funder Contribution: 76,540 GBP

    One of the regions where current global warming is most pronounced is Siberia and the Russian Far East (SRFE). Inconveniently, this is also one of the regions with least coverage of climate records in international databases. As a consequence, it is extremely difficult to analyse and understand the spatial and temporal variations of climate change in SRFE that can provide context for past changes and current warming trajectories, and data are inadequate for syntheses that can aid evaluation of simulations of past climate-an important way to assess how well models perform at projecting the future, whether it be the impact on communities and ecosystems of forest fires or the fate of carbon currently stored in soils and peatlands. The lack of records from SRFE partly reflects that there are few well established, multi-year international collaborations between Russian institutes and international partners. While scientists at Russian institutes have access to large datasets and field sites and have high-quality staff conducting laboratory analyses, they often have less access to the latest analytical approaches and data quality control protocols-or indeed the language fluency currently required for high-impact international publications and data syntheses. This can generate an imbalance of influence within projects and lead to one-sided and/or short-term scientific interactions that do not have long-term direction and coherence. We will address both the science and science culture issues via a network of researchers from the UK and six institutes of the Russian Academy of Sciences in SRFE. Partners in this network have already expressed a strong interest to work together and pool resources to (1) synthesise existing data, (2) learn new methods, and (3) together create new high-quality records of climate and environmental change in this and future research projects. Our network is called DIMA ("Developing Innovative Multi-proxy Analysis"), because we will use multiple new approaches to get climate information from sediment records (proxies) to reconstruct climate change. Our partnership-building and collaboration have several aims. First an extant dataset that described past vegetational change, which has not yet reached an international audience, will be analysed by the DIMA groups to create value-added features (e.g., data formulated for climate-vegetation modelling exercises) prior to publication. Second, we will collect samples to apply a method new to this region for reconstructing past temperatures from insect remains in lake sediments; this will be underpinned by UK-based training of Russian collaborators in the use of the latest laboratory and statistical procedures during a month-long visit of three colleagues from SRFE to the UK. It will involve collecting modern reference samples and generating a high-quality long temperature record from western Siberia as proof-of-concept for an expanded programme. Project leader van Hardenbroek is a specialist in this field. The two selected Russian Project Partners have considerable experience in organising field campaigns and laboratory analysis and will provide the necessary personnel, support and infrastructure. The new data and the experience gained during this project will place the DIMA team in a competitive position to apply for larger collaborative project; the highly motivated team will be geared up to generate long-term climate records across SRFE, produce a high-quality regional temperature synthesis, and develop collaborations with, for example, groups using data compilations to explore climate-vegetation model performance (co-I Edwards current collaboration). This proposal addresses the UK government's expressed need for developing and maintaining strong science ties with key countries, including Russia and strengthening international collaborations outside Europe post-Brexit.

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  • Funder: UK Research and Innovation Project Code: NE/R000670/1
    Funder Contribution: 419,315 GBP

    Our proposal unites a multidisciplinary team of researchers from mineralogy, palaeontology, deep-sea biology and genetics to provide an integrated picture of when and how some of the most remarkable environments on our planet were colonised by highly-specialised animals, and inform modern deep-sea conservation challenges. The discovery of hydrothermal vents in the deep sea during the late 1970s revolutionised our understanding of the limits of life on our planet. These explorations uncovered incredibly lush ecosystems supported by chemosynthesis, a carbon-fixation process previously deemed insignificant, and faunas with many novel adaptations to surviving in this dark habitat characterised by the ejection of extremely hot, toxic fluids from the seafloor. Despite their seemingly-hostile conditions, we now know that animals have thrived around vents for at least 440 million years, and that diverse taxonomic lineages have continually adapted to this environment over the course of Earth's history. Surprisingly, rather than functioning as evolutionary refuges in which ancient relict faunas have survived in isolation from large-scale environmental changes, evolution at vents appears to have occurred numerous times. This suggests that vents have an intriguing role as incubators of evolutionary novelty, their importance in evolution also highlighted by theories that life itself originated within this setting. Since their initial exploration, significant milestones have been achieved in surveying these ecosystems and in understanding the intimate interactions that modern vent faunas have with the microorganisms that support them. However, answers to fundamental questions of when animals first transitioned to occupy this environment, the processes driving the adaptation of new vent animals and the biological basis for vent colonisation are still lacking. A grasp of these principles is vitally important to understanding how animals adapt to unstable temperature regimes, and of how large-scale environmental changes affect the deep sea, the world's largest ecosystem. This is particularly pertinent today as the deep sea is increasingly affected by human activities, but how it responds to impacts such as climate change and mining operations is unknown. To gain vital evolutionary insights into the colonisation of hydrothermal vents, both in the modern ocean and throughout Earth history, we propose a comprehensive research programme guided by four hypotheses: H1) animals colonised hydrothermal vent environments soon after the Cambrian Explosion of life; H2) new vent habitat formation has repeatedly driven vent animal evolution over time; H3) ancient vent animals exhibited similar associations with microorganisms to modern vent animals to survive within harsh vent environments; and H4) adaptation to vent environmental regimes is evolutionarily rapid. We will assemble primary data for this project from field studies of key geological localities in Norway, Canada and Tasmania, which likely contain the oldest known bone-fide vent animals, and the southern Ural Mountains where a remarkable 100 million year fossil history of ancient vents is preserved. Together, these regions contain some of the best-preserved ancient hydrothermal vent deposits in the world. Collected fossil samples will be subjected to new detailed palaeontological investigations, and high resolution sulphur isotopic analyses. To investigate recent and ongoing adaptation at modern hydrothermal vents we will work on samples of traditional non-vent fauna that we can observe colonising new hydrothermal systems, using advanced DNA techniques.

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  • Funder: UK Research and Innovation Project Code: NE/K005251/1
    Funder Contribution: 339,275 GBP

    The Cambrian 'explosion' of early animal life was one of the most transformative events in Earth history, but the underlying patterns and players are difficult to resolve. The conventional shelly fossil record represents only a fraction of ancient diversity, while contemporaneous 'Burgess Shale-type' fossils are too rare and unrepresentative to track evolutionary trajectories. We have, however, identified a new and largely overlooked source of palaeontological data that promises to fill in many of the gaps. 'Small Carbonaceous Fossils' (SCFs) are organic-walled fossils that are too small to be identified on bedding surfaces, but too large and delicate to be recovered by conventional micropalaeontological techniques. Although mostly represented by disarticulated sclerites and cuticle fragments, SCFs are fundamentally more common and widely distributed than their articulated counterparts. Most significantly, the SCF record from shallow marine environments is revealing an unprecedented, and surprisingly modern, diversity of early animals, Our recent SCF work has been extraordinarily successful, but limited to 'post-explosion' phases of the Cambrian record. Here we propose to extend the study of SCFs back in time, with an eye to tracking evolutionary patterns through the Cambrian explosion and into the preceding Ediacaran Period. By far the most promising place to carry out such a study is in well-documented Precambrian-Cambrian boundary sections of the Baltic Basin. These shallow water successions are exceptionally well preserved, richly fossiliferous and easy to access - primarily through drillcore archives at the geological surveys of Estonia, Latvia, Lithuania and Sweden, along with a unique research collection at the Tallinn University. Our primary focus in the Baltic Basin will be in documenting the diversity and distribution of SCFs from the late Ediacaran through to the late Cambrian. We are particularly interested in using the SCF record to test macroevolutionary patterns derived from alternative datasets, including 'small shelly fossils' and execeptionally preseved arthropod biotas in the late Cambrian of Sweden. Microstructural analysis of problematic SCFs have the potential to identify unambiguous bilaterian animals in the Ediacaran, with major phylogenetic and macroevolutionary implications. Combined with geochemical analysis of associated palaeoenvironments, and a search for fossil biomarker molecules, these novel paleontological data will shed fundamental new light on the origin of the modern biosphere.

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  • Funder: UK Research and Innovation Project Code: NE/V001388/1
    Funder Contribution: 656,752 GBP

    Ancient records of magnetic fields stored in rocks and meteorites hold the key to answering some of the most fundamental questions in Earth and Planetary Sciences including the evolution of the Earth's Core and geodynamo, and the formation of the Solar System. In particular, it is the estimates of ancient field intensities that allows us to solve many of these questions, from constraining theories of Solar evolution, to ideas that link the start of the geodynamo to the beginning of life on Earth. To recover ancient field intensities, we study igneous rocks that have recorded thermoremanent magnetisations (TRM) during cooling. A TRM is the remanent magnetisation recorded by magnetic minerals as they cool from above the Curie temperature (~600 C) in weak magnetic fields like the Earth's. The Curie temperature is a key parameter that defines the maximum temperature at which a material exhibits magnetisation. During TRM acquisition it is assumed that the magnetic minerals are chemically stable, and do not physically or chemically alter during cooling. Such TRMs can be stable for times greater than the age of the Universe. The magnetic mineral in igneous rocks, particularly basalts, is usually titanomagnetite Fe2.4Ti0.6O4. Basalts are ubiquitous on Earth, for example, most of the top of the ocean crust (70% of the Earth's surface) is basalt. It has been known for many decades that as Fe2.4Ti0.6O4 cools it unmixes (exsolves) into a magnetic magnetite phase (Fe3O4) and a non-magnetic ulvöspinel phase (Fe2TiO4). The unmixing has been extensively studied since the 1950s and has been shown to occur at temperatures above and below the Curie temperature. The exact temperature at which unmixing stops depends on many factors like the cooling rate, with slower cooling rates more likely to give rise to exsolution structures at low temperatures. For many years palaeomagnetists who study ancient field intensities have assumed that exsolution processes stop at temperatures above the Curie temperature, and that rocks acquire TRMs; however, there is growing evidence to suggest that the minerals continue to unmix below the Curie temperature, thereby chemically alerting and recording another type of magnetic remanent magnetisation termed a thermochemical remanent magnetisation (TCRM). This is a problem, as methods for ancient magnetic field intensity determination assume that rocks carry a TRM not a TCRM. The Earth Science community maintains a database of global ancient field intensities. Analysis for this proposal indicates at least ~51% of the 4293 intensity estimates (site-level) in the database collected over the last 60 years, could be compromised by the incorrect assumption that the magnetisation is a TRM when it is in fact a TCRM. This maybe the reason for the large scatter found in the database. Hitherto little attempt has been made to determine the effect of TCRM on ancient field intensity determination, primarily because of the complexity of the problem. In recent years the PI, CoIs, Visiting Fellow and Project Partners, have developed new nanometric imaging, numerical algorithms (MERRILL) and magnetic measurement protocols to study TRM acquisition, that now make the TCRM problem tractable. We aim to nanometrically image magnetic structures in Ti-rich iron oxides during unmixing at temperature, to allow us to understand how the magnetisation is affected by the unmixing process. We will combine this information with nanometric chemical mapping to build numerical models, using a new multiphase addition to MERRILL. The numerical model will allow us to: (1) make predictions which we will ground-truth against magnetic measurements, (2) determine the stability of TCRM on geological timescales, and (3) to determine the contribution of TCRM to ancient magnetic field intensity determinations. We will use the results to develop new ancient field intensity estimations protocols and provide corrections to legacy data.

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