
In a multi-cellular organism all cells inherit the same genetic information in the form of DNA. The information in the DNA is typically decoded to make proteins or RNA. As the organism develops some cells will decode particular DNA sequences (genes) into proteins and RNA, whilst other cells will not. In recent years a great deal has been learnt about the different molecules, which are involved in carrying out this process. Typically, specific proteins bind near the beginning of a particular DNA sequence (gene) to initiate the decoding; these proteins are called transcription factors and they recognise and bind to particular genes. However, the DNA within the cell is packaged in bundles with structural proteins (called histones). Recently, it has become clear that this packaging can be controlled by proteins in a gene-specific manner. We suspect that the packaging of the DNA can lead to particular sequences being hidden away inside a complex structure so that decoding no longer occurs. This may be likened to reading a book where what can be read is controlled by whatever opens the book at particular pages. Several mechanisms for the control of this 'page reading' are now being studied very intensively. We aim to study a class of proteins that are in some way involved in the regulation of gene transcription at this level of DNA packaging. How they work is not yet clear, but the studies that we have carried out so far have provided a hypothesis from which we can begin to explore further. An important feature of the class of proteins we intend to study is that they interact with many partners to form a fully functional protein complex. We are planning to determine the structure of a particular building block (a protein domain) and then study how it interacts with key partner proteins. Using this information we will then carry out further experiments designed to follow directly the interactions in vivo and establish how this domain functions within the complex to regulate DNA packaging.
<script type="text/javascript">
<!--
document.write('<div id="oa_widget"></div>');
document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=ukri________::cec62588009aae193357406ce2358a14&type=result"></script>');
-->
</script><script type="text/javascript">
<!--
document.write('<div id="oa_widget"></div>');
document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=ukri________::cec62588009aae193357406ce2358a14&type=result"></script>');
-->
</script>At 3:36 AM on the 24th of August a magnitude 6.2 earthquake struck the Amatrice region. The shaking in this event caused nearly 300 deaths and significant damage to the villages distributed across the region. The earthquake ruptured across two faults, the Laga-Amatrice and Vettore faults, which were previously thought to be separate structures that could not rupture in a single event. Our team visited the region days after the event to begin scientific study of this earthquake, investigating the surface expression of the earthquake and installing GNSS equipment that will measure high-resolution motion of the ground continuously for weeks and months following the earthquake. Our team comprises UK and Italian scientists from the University of Leeds, University of Durham, Univeristy of London, Birkbeck University of London, University of Insurbia, the Italian Geological Survey (ISPRA), and Geospatial Research Ltd (Durham). Members of our team who are experts in using satellite data to investigate ground deformation (Durham) processed data in real-time to direct the initial field campaign. This project will aim to fully characterise the nature of the Amatrice earthquake in terms of what happened during and what is continuing to occur after the seismic event. We will use a variety of techniques including satellite radar measurements and modelling of co and post -seismic deformation, GNSS (Global Navigation Satellite System) measurements of ground deformation, photogrammetry and laser scanning to make high resolution measurements of the surface rupture, detailed field work in the region of the earthquake, and modelling techniques to determine how this earthquake affected stress on the surrounding faults. The work is urgent due to the need to document post-seismic deformation in the weeks and months following the earthquake, and the degrading nature of the surface rupture. This research will allow us to investigate fault connectivity and how linkage develops. We will test hypotheses regarding the role of postseismic deformation after an earthquake that links previously independent structures. Fault linkage typically happens over long geological timescales and has never before been captured before with such a high quality dataset. Our results will be important for incorporating multi-fault rupturing earthquakes into future hazard assessments made in central Italy and globally.
<script type="text/javascript">
<!--
document.write('<div id="oa_widget"></div>');
document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=ukri________::42b34a35e84bf0395e471f10d54663fb&type=result"></script>');
-->
</script><script type="text/javascript">
<!--
document.write('<div id="oa_widget"></div>');
document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=ukri________::42b34a35e84bf0395e471f10d54663fb&type=result"></script>');
-->
</script>Black holes are incredibly fascinating objects. They largely populate the Universe we live in, attracting whole galaxies around them. They also attract the imagination of novel writers and scientists alike: they represent the ultimate frontier at which our knowledge and intellect can be put to the test. In 1974 Stephen Hawking, building upon suggestions that black holes have a finite temperature, predicted that the event horizon surrounding a black hole separates regions characterized by such an intense space-time distortion that photons and particles are literally ripped out of vacuum state. These photons are then seen from outside the black hole to be emitted as a continuous flux of radiation. Black holes glow, just as if they were light bulbs. Unfortunately, this truly amazing prediction has little hope of being verified directly from astrophysical black holes. The "glow" has an extremely low temperature, of the order of tens of nano-Kelvins and cannot be distinguished amongst the much higher cosmic background temperature. Fortunately, exactly 30 years ago, William Unruh noted that the same arguments that lead to black hole evaporation also predict that a thermal spectrum of sound waves should be given out from a flowing fluid whose velocity is made to vary from sub-sonic to super-sonic velocities. Sound waves will remain blocked at the transition between the sub- and super-sonic regions at what, to all effects, is the analogue of an horizon. It now turns out that horizons are apparently far more common than one may imagine. They appear in flowing tap water as it hits the sink and in a number of water or liquid based scenarios; they appear in flowing Bose-Einstein-Condensates, in polariton condensates and, most importantly for what concerns this project, in moving dielectric media. We may imagine moving a transparent glass sample at velocities close to that of light. We would then have a situation analogous to that of sound waves in a moving fluid: in the presence of a transition from sub-luminal to super-luminal speeds, light waves will not be able to move beyond the horizon point at which the medium velocity is exactly equal to the phase velocity of light. One of the PIs (U. Leonhardt) recently proposed an ingenious method to achieve such horizons in a very simple manner. An intense laser pulse propagating in glass will create a local perturbation in the refractive index that travels together with the pulse, i.e. it naturally travels at light speeds. Any light wave approaching the perturbation will be slowed down by the local increase in refractive index and will eventually be blocked at the horizon beyond which it will be never be able to propagate. Using this very simple proposal, the other project PI (D. Faccio) obtained the first evidence of spontaneous photon emission induced by the dielectric horizon. The perturbation is glowing and evaporating by shedding photons excited from the vacuum state, just as Hawking predicted black holes should do. This project aims at taking forth these results and taking studies on Hawking emission and horizon related effects to the next level. We are now able to plan real experiments that can give us for the first time real data describing how horizons interact with the quantum vacuum. Moreover, at the heart of Hawking emission lies a novel amplification mechanism that, due to the lack of any previous experimental possibilities, has never been truly investigated before. This new amplification channel will be studied and used to amplify light. The goal in mind is to create the first black hole laser in which light is trapped in between two separate horizons. Bouncing back and forth it is amplified at each rebound and finally exponentially explodes in laser-like amplification process. The impact of this project therefore goes well beyond investigation of Hawking effects and invests a number of fields, ranging from quantum field theories to nonlinear optics and photonic technologies.
<script type="text/javascript">
<!--
document.write('<div id="oa_widget"></div>');
document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=ukri________::7220d10d4a64912a0bbad5825b6f2939&type=result"></script>');
-->
</script><script type="text/javascript">
<!--
document.write('<div id="oa_widget"></div>');
document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=ukri________::7220d10d4a64912a0bbad5825b6f2939&type=result"></script>');
-->
</script>Seismic hazard assessment and understanding of continental deformation are hindered by unexplained slip-rate fluctuations on faults, associated with (a) temporal clusters of damaging earthquakes lasting 100s to 1000s of years, and (b) longer-term fault quiescence lasting tens to hundreds of millennia. We propose a new unified hypothesis explaining both (a) and (b), involving stress interactions between fault/shear-zones and neighbouring fault/shear-zones; however key data to test this are lacking. We propose measurements and modelling to test our hypothesis, which have the potential to quantify the processes that control continental faulting and fluctuations in the rates of expected earthquake occurrence, with high societal impact. Our aspiration is that cities and critical facilities worldwide will gain additional protection from seismic hazard through use of the calculations we pioneer herein. The background is that slip-rate fluctuations hinder understanding because they introduce uncertainty about whether specific faults are active or not. For example, a review in Japan of earthquake risk to critical facilities, such as the Tsuruga nuclear power plant (NPP), revealed a geological fault under a nuclear reactor (Chapman et al. 2014). The question that arose was whether the fault was active or not. Japan's Nuclear Regulatory Authority (NRA) has guidelines defining fault activity, and considered the fault under the reactor to be active, evidenced by faulting in sediments <~125,000 years in age. The Japan Atomic Energy Power Company (JPAC) disagreed, following study by an independent team of geoscientists. In 2014, the Tsuruga NPP remained closed due to ongoing debate between the NRA and JPAC, with similar debates ongoing for other NPPs. We suggest that defining fault activity as simply "active" or "inactive" is unsatisfactory because it is debatable even amongst experts. In fact a fault that has not slipped in many millennia may, in reality, not be inactive, but instead may simply have a low slip-rate, with the capability to host a damaging earthquake after a long recurrence interval. Our breakthrough is we think slip-rate fluctuations over both timescales (a and b) are a continuum, sharing a common cause involving interaction between fault/shear-zones. For the first time, we provide calculations that describe this interaction, quantifying slip-rate fluctuations and seismic hazard in terms of probabilities. We show that slip during an earthquake cluster on a brittle fault in the upper crust occurs in tandem with high strain-rate on the viscous shear-zone underlying the fault. This deformation of the crust produces changes in differential stress on neighbouring fault/shear-zones. Viscous strain-rate is known to be proportional to differential stress, so, given data on slip-rate fluctuations one can calculate changes in differential stress, and then calculate implied changes to viscous strain-rates on receiver shear zones and slip-rates on their overlying brittle faults. We provide a quantified example covering several millennia, but lack data allowing a test over tens to hundreds of millennia. If we can verify our hypothesis over both timescales, through successful replication of measurements via modelling, we will have identified and quantified a hitherto unknown fundamental geological process. We will study the Athens region, Greece, where a special set of geological attributes allows us to measure and model slip-rate fluctuation over both time scales (a and b), the key data combination never achieved to date. We know of no other quantified explanation that links slip-rate fluctuations over the two timescales; the significance and impact of accomplishing this is that it has the potential to change the way we mitigate hazard for cities and critical facilities. Chapman et al. 2014, Active faults and nuclear power plants, EOS, 95, 4
<script type="text/javascript">
<!--
document.write('<div id="oa_widget"></div>');
document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=ukri________::de0e7ec1656e9998fb1950f014b2b446&type=result"></script>');
-->
</script><script type="text/javascript">
<!--
document.write('<div id="oa_widget"></div>');
document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=ukri________::de0e7ec1656e9998fb1950f014b2b446&type=result"></script>');
-->
</script>