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  • richardmitnick 12:42 am on May 13, 2018 Permalink | Reply
    Tags: , ICL-Imperial College London, , , , X-rays from tabletop lasers allows scientists to peer through the ‘water window’   

    From Imperial College London: “X-rays from tabletop lasers allows scientists to peer through the ‘water window’” 

    Imperial College London
    From Imperial College London

    11 May 2018
    Hayley Dunning

    1

    Studying the fleeting actions of electrons in organic materials will now be much easier, thanks to a new method for generating fast X-rays.

    The technique means advanced measurements of fast reactions will now be possible in physics labs around the world, without having to wait to use expensive and scarce equipment. It could be used, for example, to study and improve light-harvesting technologies like solar panels and water splitters.

    When ‘soft’ X-rays, beyond the range of ultraviolet light, strike an object, they are strongly absorbed by some kinds of atoms and not others. In particular, water is transparent to these X-rays, but carbon absorbs them, making them useful for imaging organic and biological materials.

    However, a challenge has been to generate very fast soft X-rays. Creating pulses of X-rays that only last one thousandth of a millionth of a millionth of a second would allow researchers to image the extremely quick motions of electrons, crucial for determining how charge travels and reactions occur.

    Smallest and fastest reaction steps

    Fast soft X-rays have been created with large facilities, such as multi-billion dollar costing free-electron lasers, but now a research team from Imperial College London have generated fast and powerful fast soft X-ray pulses using standard laboratory lasers.

    The method, which can produce bright soft X-ray pulses that last hundreds of attoseconds (quintillionths of a second), is published today in Science Advances.

    With the new technique, researchers will be able to watch the movement of electrons on their natural timescale, giving them a dynamic picture of the smallest and fastest reaction steps.

    Senior author Professor Jon Marangos, from the Department of Physics at Imperial, said: “The strength of this technique is that it can be used by many physics labs around the world with lasers they already have installed.

    “This discovery will allow us to make measurements at extreme timescales for the first time. We are at the frontiers of what we can measure, seeing faster-than-ever processes important for science and technology.”

    Generating X-rays

    Generating X-rays in a lab requires exciting atoms until they release photons – particles of light. Normally, atoms in a long, dispersed cloud are excited in sequence so that they emit photons in ‘phase’, meaning they add up and create a stronger X-ray pulse. This is known as phase matching.

    But when trying to generate soft X-rays this way, effects in the cloud of atoms strongly defocus the laser, disrupting phase matching.

    Instead, the team discovered that they needed a thin, dense cloud of atoms and short laser pulses. With this setup, while the photons could not stay in phase over a long distance, they were still in phase over a shorter distance and for a short time. This led to unexpectedly efficient production of the short soft X-ray pulses.

    The team further measured and simulated the exact effects that cause high harmonic generation in this situation, and from this were able to predict the optimum laser conditions for creating a range of X-rays.

    Lead researcher Dr Allan Johnson, from the Department of Physics at Imperial, said: “We’ve managed to look inside what was before the relatively black-box of soft X-ray generation, and use that information to build an X-ray laser on a table that can compete with football-field spanning facilities. Knowledge is quite literally power in this game.”

    Improving solar technologies

    The team at Imperial plan to use the technique to study organic polymer materials, in particular those that harvest the Sun’s rays to produce energy or to split water. These materials are under intense study as they can provide cheaper renewable energy.

    However, many currently used materials are unstable or inefficient, due to the action of electrons that are excited by light. Closer study of the fast interactions of these electrons could provide valuable insights into methods for improving solar cells and catalysts.

    • ‘High-Flux Soft X-ray Harmonic Generation from Ionization-Shaped Few-Cycle Laser Pulses’ by Allan S. Johnson, Dane R. Austin, David A. Wood, Christian Brahms, Andrew Gregory, Konstantin B. Holzner, Sebastian Jarosch, Esben W. Larsen, Susan Parker, Christian S. Strüber, Peng Ye, John W. G. Tisch, and Jon P. Marangos is published in Science Advances.

    See the full article here .

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    Imperial College London

    Imperial College London is a science-based university with an international reputation for excellence in teaching and research. Consistently rated amongst the world’s best universities, Imperial is committed to developing the next generation of researchers, scientists and academics through collaboration across disciplines. Located in the heart of London, Imperial is a multidisciplinary space for education, research, translation and commercialisation, harnessing science and innovation to tackle global challenges.

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  • richardmitnick 2:39 pm on December 7, 2017 Permalink | Reply
    Tags: A space mission to test how objects fall in a vacuum has released its first results providing an improved foundation for Einstein's famous theory, , , , , , , ICL-Imperial College London, , , The theory is fundamentally incompatible with another well-tested theory: quantum mechanics which describes the physics of the extremely small, The theory of general relativity and the conclusions it draws about gravity have been shown to be true wherever tested, This first result is going to shake the world of physics and will certainly lead to a revision of alternative theories to general relativity   

    From ICL: “European satellite confirms general relativity with unprecedented precision” 

    Imperial College London
    Imperial College London

    07 December 2017
    Hayley Dunning

    A space mission to test how objects fall in a vacuum has released its first results, providing an improved foundation for Einstein’s famous theory.

    The first results of the ‘Microscope’ satellite mission were announced this week by a group of researchers led by the French space agency CNES and including Imperial scientists. The findings are published in the journal Physical Review Letters.

    CNES Microscope satellite

    Launched in April 2016, the mission set out to test the ‘equivalence principle’, the founding assumption of Einstein’s theory of general relativity. The theory poses that gravity is not a ‘pulling’ force, but is the result of large bodies, like the Earth, bending spacetime.

    As a result, when two objects are dropped in a vacuum under the same force of gravity, they fall at the same rate, no matter what their difference in weight or composition. This principle was demonstrated by Apollo 15 astronaut David Scott, who dropped a hammer and a feather on the Moon and showed them both reaching the ground at the same time.

    However, dropping household objects on the lunar surface does not allow very precise measurements – it could be that they reach the ground fractions of a second apart. This is important for scientists to know, because if the equivalence principle does not hold absolutely, then it could provide clues to a unifying theory of physics.

    Finding a single theory

    The theory of general relativity, and the conclusions it draws about gravity, have been shown to be true wherever tested. However, the theory is fundamentally incompatible with another well-tested theory: quantum mechanics, which describes the physics of the extremely small.

    The major goal for 21st Century physics is a single theory that ties them all together neatly. Certain candidate theories predict that the equivalence principle may be violated at very weak levels.

    The new results have measured the equivalence principle with ten times the precision of any previous experiment, and show that objects in a vacuum fall with the same acceleration.

    Professor Timothy Sumner, from the Department of Physics at Imperial was involved in the early discussions for the project thirty years ago, which led to the current mission. He more recently joined the Science Working Team. Commenting on the latest results, he said: “The equivalence principle has proven unshakeable yet again.

    “This result is the first new measurement for several years and demonstrates the possibility of taking such difficult ‘laboratory’ experiments into the quiet and interference-free space environment. There will more results from this impressive experiment.”

    1,900 orbits of the Earth

    To test the principle, the Microscope satellite contains a series of ‘test masses’: blocks of metals of different weights with very precisely measured properties. These masses are isolated from any other influence and are monitored as they freefall in space while orbiting the Earth.

    This means their acceleration due to the freefall can be measured and compared to test the equivalence principle. If two test masses of equal size but different composition are accelerated differently during the freefall, then the equivalence principle is violated.

    The science phase of the mission began in December 2016 and has already collected data from 1,900 orbits of the Earth. This means that altogether the objects have been freefalling in space for the equivalent of 85 million kilometres, or half the Earth-Sun distance.

    The mission’s principle investigator, Pierre Touboul from France’s national aerospace research centre, ONERA, said: “The satellite’s performance is far exceeding expectations. Data from more than 1,900 additional orbits are already available and more are to come.

    “This first result is going to shake the world of physics and will certainly lead to a revision of alternative theories to general relativity.”

    The Microscope experiment is continuing to collect data, and the team hope that the final analysis will have a precision within a tenth of a trillionth of a percent.

    See the full article here .

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    Imperial College London

    Imperial College London is a science-based university with an international reputation for excellence in teaching and research. Consistently rated amongst the world’s best universities, Imperial is committed to developing the next generation of researchers, scientists and academics through collaboration across disciplines. Located in the heart of London, Imperial is a multidisciplinary space for education, research, translation and commercialisation, harnessing science and innovation to tackle global challenges.

     
  • richardmitnick 6:07 am on October 25, 2017 Permalink | Reply
    Tags: , , , Herbivores help protect marine ecosystems from climate change, ICL-Imperial College London   

    From ICL: “Herbivores help protect marine ecosystems from climate change” 

    Imperial College London
    Imperial College London

    25 October 2017
    Hayley Dunning

    1
    A limpet on seaweed. Image: Rebecca Kordas

    Plant-eating critters are key to helping ecosystems survive global warming, offering some hope for a defence strategy against climate change.

    An international research team created miniature marine ecosystems and tested how they fared in warmer conditions. They found that in the hottest conditions, ecosystems that included limpets – voracious snail-like marine herbivores – fared the best.

    The study, published in Science Advances, monitored mini ecosystems on rocky shores made up of different collections of organisms. The ecosystems were grown on special hard plastic plates that could be individually warmed. This allowed the researchers to test how the different ecosystems responded to temperature rises while in their natural habitat.

    Ecosystems are in a delicate balance: removing organisms that do key jobs can cause the whole system to deteriorate. If this ecosystem is then put under stress, it is less able to cope and can collapse.

    In these experiments, it was the key job performed by the main herbivore (limpets) that helped the ecosystems stay resilient in the face of warming. Limpets are voracious consumers of algae, and their action prevents algae from building up and using all the available space – a valuable resource on rocky shores.

    Variety needed

    Lead author of the study Dr Rebecca Kordas, who completed this research for her PhD at the University of British Columbia and is now a research fellow at Imperial College London, said: “The herbivores created space for other plants and animals to move in and we saw much more diversity and variety in these ecosystems.

    “We want variety because we found it helps protect the ecosystem when you add a stressor like heat.”

    2
    The experimental plates underwater. Image: Rebecca Kordas

    The research team studied life in the intertidal zone, the area of the shore between the low tide and high tide, on the coast of British Columbia. This area is home to a community of starfish, anemones, mussels, barnacles and seaweed. As the tide moves in and out, the plants and animals must cope with huge variation in temperature every day, sometimes as much as 20 to 25 degrees Celsius.

    Despite dealing daily with these extremes, the ecosystems can be severely damaged by further warming. Dr Kordas said: “When heat waves come through British Columbia and the Pacific Northwest, we see mass mortality of numerous intertidal species.

    “These creatures are already living at their physical limits, so a two-degree change – a conservative prediction of the warming expected over the next 80 years or so – can make a big difference.”

    Making ecosystems more resilient

    The researchers found that in the summer, when temperatures were at their warmest, communities could fare well even if they were heated, but only if limpets were present. Dr Kordas added: “When limpets were part of the community, the effects of warming were less harsh.”

    3
    Plates along the shore in Ruckle Park, British Columbia. Image: Rebecca Kordas

    Senior study author Professor Christopher Harley from the University of British Columbia says that, in general – consumers like limpets, sea otters or starfish are very important to maintaining biodiversity, especially in aquatic ecosystems. Losing these species can destabilize ecosystems, but protecting them can make ecosystems more resilient.

    “We should be thinking of ways to reduce our negative effects on the natural environment and these results show that if we do basic conservation and management, it can make a big difference in terms of how ecosystems will weather climate change,” Professor Harley said.

    See the full article here .

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    Imperial College London

    Imperial College London is a science-based university with an international reputation for excellence in teaching and research. Consistently rated amongst the world’s best universities, Imperial is committed to developing the next generation of researchers, scientists and academics through collaboration across disciplines. Located in the heart of London, Imperial is a multidisciplinary space for education, research, translation and commercialisation, harnessing science and innovation to tackle global challenges.

     
  • richardmitnick 1:16 pm on October 7, 2017 Permalink | Reply
    Tags: , , ICL-Imperial College London, ,   

    From ICL via Science Alert: “We Finally Know The Weird Way Electrons Behave During Fusion-Like Conditions” 

    Imperial College London
    Imperial College London

    Science Alert

    6 OCT 2017
    KARLA LANT

    1
    Imperial College London

    Fusion energy just got one step closer.

    Researchers have at last been able to model the behaviour of electrons under extreme densities and temperatures, similar to those found inside stars and planets.

    Although electrons are ubiquitous in our universe, carrying electrical current and determining the physical properties of materials, physicists have never before been able to describe the ways large numbers of electrons behave together- especially at high densities and temperatures.

    This new research [Physical Review Letters] could shed light on the how matter behaves in fusion experiments, in turn leading to a new source of clean fusion energy.

    Imperial College London Department of Physics Professor Matthew Foulkes told Phys.org:

    “Now, at last, we are in a position to carry out accurate and direct simulations of planetary interiors; solids under intense laser irradiation; laser-activated catalysts; and other warm dense systems.”

    He added, “This is the beginning of a new field of computational science.”

    Although it is easy enough to describe the large-scale behaviours of electrons- such as how electrical current, resistance, and voltage work- quantum forces control the behaviours of electrons at the microscopic level, causing them to act like a quantum mechanical gas.

    Until the success of this research, scientists were only able to create simulations that described the behaviour of this electron gas at very low temperatures.

    However, the centres of planets like Earth and stars are filled with warm, dense matter – matter that is also critical to fusion experiments.

    With the help of computer simulations, the new work solves the equations that describe the electron gas precisely. The team has thus completely described the thermodynamic properties of interacting electrons in warm dense matter for the first time.

    Kiel University Professor of Theoretical Physics Michael Bonitz told Phys.org:

    “These results are the first exact data in this area, and will take our understanding of matter at extreme temperatures to a new level. Amongst other things, the 40-year-old existing models can now be reviewed and improved for the first time.”

    See the full article here .

    Please help promote STEM in your local schools.

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    Imperial College London

    Imperial College London is a science-based university with an international reputation for excellence in teaching and research. Consistently rated amongst the world’s best universities, Imperial is committed to developing the next generation of researchers, scientists and academics through collaboration across disciplines. Located in the heart of London, Imperial is a multidisciplinary space for education, research, translation and commercialisation, harnessing science and innovation to tackle global challenges.

     
  • richardmitnick 11:04 am on September 28, 2017 Permalink | Reply
    Tags: "Science knows no boundaries", , , Global showcase, ICL-Imperial College London,   

    From ICL: “Japanese collaborations reach new heights” 

    Imperial College London
    Imperial College London

    Tokyo Tech

    28 September 2017
    Andrew Scheuber
    Colin Smith

    Imperial and one of Japan’s top universities joined forces at a two-day workshop in London this week.

    The 2nd Tokyo Tech-Imperial Workshop, brought together some of the world’s leading researchers to explore new collaborations in bioscience and its links with technology, encompassing expertise in synthetic biology, data science and neurotechnology.

    Imperial’s Provost James Stirling opened the conference, welcoming back Tokyo Tech’s President Yoshinao Mishima and praising “plans for enhancing collaboration between our two great institutions.”

    “Although this is about promoting new collaborations, the two universities are old friends,” he said.

    Imperial and one of Japan’s top universities joined forces at a two-day workshop in London this week.

    The 2nd Tokyo Tech-Imperial Workshop, brought together some of the world’s leading researchers to explore new collaborations in bioscience and its links with technology, encompassing expertise in synthetic biology, data science and neurotechnology.
    James Stirling

    Provost James Stirling opening the
    workshop

    Imperial’s Provost James Stirling opened the conference, welcoming back Tokyo Tech’s President Yoshinao Mishima and praising “plans for enhancing collaboration between our two great institutions.”

    “Although this is about promoting new collaborations, the two universities are old friends,” he said.

    “There was a considerable amount of excitement within our academic community as the plans for this day materialised, with many of our brightest and best researchers eager to take part. With such complementary expertise at our institutions – in fields ranging from robotics to neurosciences to chemical biology – I am certain that with such a deep well of goodwill on either side that we can build on our existing partnership, and expand into new and exciting areas.”

    President Mishima said he was “pleased to see the growing collaborations between our institutions, especially in big data, synthetic biology and neurotechnology,” which have resulted in significant academic exchanges and research discoveries. These include Professor Sergei Kazarian’s support for Tokyo Tech colleagues in spectroscopic imaging, which was “an inspiration to our students and researchers alike.”

    “Science knows no boundaries”

    Professor Rod Smith, who has been collaborating with Tokyo Tech engineers since the 1970s, emphasised the very long-term nature of London and Imperial’s connections with Japan, dating back to the 19th century. These ties include the father of seismology John Milne (1850 – 1913) who, after graduating from the Royal School of Mines, made some of his most important discoveries at Tokyo’s Imperial College of Engineering.

    Professor Maggie Dallman, Associate Provost (Academic Partnerships), was the driving force behind the Tokyo Tech-Imperial workshop series, the first of which was held in Japan in 2016.

    Professor Dallman spoke about the two universities’ aim of “tackling grand challenges relevant to the UK, Japan and the world,” taking advantage of complementary expertise, matching projects to funding opportunities in the UK and Japan, and PhD student exchanges. She said the two institutions see “the role of universities as not just in science but in promoting social cohesion.”

    Japan’s Ambassador to the UK Koji Tsuruoka said that soon after arriving in London “Imperial College was a ‘must visit’ for me. Imperial demonstrates the quality of British science,” and “Tokyo Tech is a very appropriate counterpart to Imperial.”

    “Science knows no boundaries,” he added, so it is right that the two universities “will contribute to the future prospects of the whole world – not just the UK and Japan.”

    Global showcase

    London correspondents from the Nikkei, the world’s highest circulation financial newspaper, and the Tokyo Shimbun, one of Japan’s most respected quality newspapers, attended the workshop and toured the College.

    They visited labs, met Imperial academics and some of the College’s 75 Japanese students. They also interviewed Professors Stirling and Mishima about the two universities’ collaborations and aspirations. When asked about Imperial’s position in the world top ten of major university rankings, Professor Stirling said “The secret of our success is that we’re a global institution”.

    Hydrodynamics pioneers

    The guests toured the Hydrodynamics laboratory, based in the Department of Civil and Environmental Engineering. The lab consists of state-of-the-art wave tank facilities, covering a floor area of some 3,000 square metres.

    2
    Dr Marios Christou simulated conditions in the ocean, creating different wave formations and wind conditions for the visitors. The Imperial researcher also showed a device for creating tsunamis in a wave tank, which was of special interest to the journalists.

    n another demonstration, Dr Henry Burridge demonstrated how these tanks could be used to model airflow. In particular, they were using fluids to model how smoke travels through buildings, which could have applications for improving airflow in houses in developing countries where open fires are common. By using a coloured brine solution, which is heavier than the tank water it travels through, Dr Burridge was able to simulate how the solution travelled through rooms in a similar way to smoke.

    Robotic surgery innovators

    Professor Guang-Zhong Yang, who leads the Hamlyn Centre, spoke about the latest robotic technologies that he and his team are developing to reshape the future of healthcare for both developing and developed countries.

    Professor Yang and his team are working closely with academic institutions and industry in Japan to develop robotics that is smaller than the width of a human hair. In the near future, these devices will be inserted into the body to deliver treatments to targeted zones, which could improve outcomes and recovery times for patients.

    See the full article here .

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    tokyo-tech-campus

    Tokyo Tech is the top national university for science and technology in Japan with a history spanning more than 130 years. Of the approximately 10,000 students at the Ookayama, Suzukakedai, and Tamachi Campuses, half are in their bachelor’s degree program while the other half are in master’s and doctoral degree programs. International students number 1,200. There are 1,200 faculty and 600 administrative and technical staff members.

    In the 21st century, the role of science and technology universities has become increasingly important. Tokyo Tech continues to develop global leaders in the fields of science and technology, and contributes to the betterment of society through its research, focusing on solutions to global issues. The Institute’s long-term goal is to become the world’s leading science and technology university.

    Imperial College London

    Imperial College London is a science-based university with an international reputation for excellence in teaching and research. Consistently rated amongst the world’s best universities, Imperial is committed to developing the next generation of researchers, scientists and academics through collaboration across disciplines. Located in the heart of London, Imperial is a multidisciplinary space for education, research, translation and commercialisation, harnessing science and innovation to tackle global challenges.

     
  • richardmitnick 10:39 am on April 6, 2017 Permalink | Reply
    Tags: , Brexit 1.0: scientists find evidence of Britain's separation from Europe, , ICL-Imperial College London   

    From ICL: “Brexit 1.0: scientists find evidence of Britain’s separation from Europe” 

    Imperial College London
    Imperial College London

    04 April 2017
    Colin Smith

    Researchers have found evidence of how ancient Britain separated from Europe, which happened in two stages, they report in Nature Communications.

    1
    Artist’s impression of the ancient land bridge. Credit: Imperial College London/Chase Stone

    Nearly 450,000 years ago, when Earth was in the grip of an ice age, ice stretched right across the North Sea, from Britain to Scandinavia. The low sea levels meant that the entire English Channel was dry land, a frozen tundra landscape, crisscrossed by small rivers.

    Britain’s separation from mainland Europe is believed to be the result of spill over from a proglacial lake – a type of lake formed in front of an ice sheet – in the North Sea, but this has remained unproven. Now, researchers from Imperial College London and their colleagues from institutes in Europe show that the opening of the Dover Strait in the English Channel occurred in two episodes, where an initial lake spill over was followed by catastrophic flooding.

    Ten years ago, the researchers from Imperial College London revealed geophysical evidence of giant valleys on the seafloor in the central part of English Channel. They believed these valley networks were evidence of a megaflood gouging out the land, which they speculated may have been caused by a catastrophic breach in a chalk rock ridge joining Britain to France.

    The new study by the team, working with their colleagues in Europe, now shows for the first time the details of how this chalk ridge in the Dover Strait, between Dover and Calais, was breached. New geophysical data collected by colleagues from Belgium and France has been combined with seafloor data from the UK showing evidence of huge holes and a valley system located on the seafloor.

    The team show that the chalk ridge acted like a huge dam and behind it was a proglacial lake. This lake was first hypothesised by scientists more than 100 years ago and the authors of today’s study show how the lake overflowed in giant waterfalls, eroding the rock escarpment, weakening it and eventually causing it to fail and release huge volumes of water onto the valley floor below.

    The team believe that the huge holes that they analysed on the seafloor are plunge pools, created when water cascading over an escarpment hit the ground and eroded rock. The plunge pools in the Dover Strait are huge – up to several kilometres in diameter and around 100 metres deep and were drilled into solid rock. Around seven plunge pools run in a line from the ports of Calais to Dover. The researchers suggest these plunge pools are evidence of an overflow of water from the lake in the southern North Sea.

    The straight line of the plunge pools suggests they were cascading off one single rock ridge perhaps 32 kilometres long and 100 metres high– the land bridge between Europe and the UK.

    The researchers have also found evidence that a second event fully opened the Dover Strait. Later on, perhaps hundreds of thousands of years later, a new valley system, the Lobourg Channel, was carved by megaflood processes that crossed the Dover Strait. The researchers demonstrate that this valley system is connected to the giant valley network in the central English Channel. They suggest that a spill over of other, smaller lakes in front of the ice sheets in the North Sea may have been responsible for the later episode of flood erosion.

    Putting the puzzle together

    It has taken ten years, but by pulling all the pieces of the geological jigsaw puzzle together the team say they are more confident about what may have caused the megaflood in the English Channel thousands of years ago.

    Dr Jenny Collier, a co-author of the study from the Department of Earth Science and Engineering at Imperial College London, said: “Based on the evidence that we’ve seen, we believe the Dover Strait 450,000 years ago would have been a huge rock ridge made of chalk joining Britain to France, looking more like the frozen tundra in Siberia than the green environment we know today. It would have been a cold world dotted with waterfalls plunging over the iconic white chalk escarpment that we see today in the White Cliffs of Dover.

    “We still don’t know for sure why the proglacial lake spilt over. Perhaps part of the ice sheet broke off, collapsing into the lake, causing a surge that carved a path for the water to cascade off the chalk ridge. In terms of the catastrophic failure of the ridge, maybe an earth tremor, which is still characteristic of this region today, further weakened the ridge. This may have caused the chalk ridge to collapse, releasing the megaflood that we have found evidence for in our studies.”

    Engineers first found evidence of the plunge pools when they were carrying out geological surveys of the Dover Strait seafloor back in the 1960s. No one knew what caused them, but they were called the Fosse Dangeard. The loose gravel and sand infilling these plunge pools meant that the engineers had to move the route of the Channel Tunnel to avoid them. In 1985 a marine geologist named Professor Alec Smith, from Bedford College in London, first proposed that the holes were created by ancient waterfalls, but the lack of hard evidence meant that the assertions were largely forgotten. Now, the authors of today’s study say Smith’s original assertions were right.

    The scientists say if it wasn’t for a set of chance geological circumstances, Britain may have still remained connected to mainland Europe, jutting out into the sea similarly to Denmark.

    Professor Sanjeev Gupta, a co-author from the Department of Earth Science and Engineering at Imperial, added: “The breaching of this land bridge between Dover and Calais was undeniably one of the most important events in British history, helping to shape our island nation’s identity even today. When the ice age ended and sea levels rose, flooding the valley floor for good, Britain lost its physical connection to the mainland. Without this dramatic breaching Britain would still be a part of Europe. This is Brexit 1.0 – the Brexit nobody voted for.”

    The team still do not have an exact timeline of events. In the next step, the researchers would like to take core samples of the in-filled sediments in the plunge pools, which they will analyse to determine the timing of erosion and infill of the plunge pools, the environments represented by these sediments, and the source of the sediments. Developing a timeline of events would enable them to learn more about the distinctive evolution of Britain, compared to mainland Europe. However, this will be a real challenge for the team as getting sediment core samples in the Dover Strait means dealing with huge tidal changes and traversing the world’s busiest shipping lane.

    The study was carried out in conjunction with researchers from Royal Observatory Belgium; Ghent University, Belgium; CNRS, the University of Lille, and the University of Western Britanny in France; and Top-Hole Studies Ltd, UK.

    See the full article here .

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    Imperial College London

    Imperial College London is a science-based university with an international reputation for excellence in teaching and research. Consistently rated amongst the world’s best universities, Imperial is committed to developing the next generation of researchers, scientists and academics through collaboration across disciplines. Located in the heart of London, Imperial is a multidisciplinary space for education, research, translation and commercialisation, harnessing science and innovation to tackle global challenges.

     
  • richardmitnick 9:30 am on March 29, 2017 Permalink | Reply
    Tags: , , , , , ICL-Imperial College London,   

    From ICL: “Imperial instrument ready to study the Sun” 

    Imperial College London
    Imperial College London

    29 March 2017
    Hayley Dunning
    Thomas Angus [Photographer]

    1
    Artist’s impression of the Solar Orbiter. Credit: ESA/AOES

    Imperial’s contribution to the Solar Orbiter mission, which will go closer to the Sun than anything so far, is ready to fly after extensive testing.

    Solar Orbiter is a European Space Agency mission carrying ten instruments to measure many different properties of the Sun and interplanetary space.

    Aboard the spacecraft, launching in early 2019, will be a magnetometer instrument built by a team from the Department of Physics at Imperial.

    The magnetometer will measure the Sun’s magnetic field in interplanetary space, carried by the solar wind. The solar wind is a stream of charged particles coming off the Sun that fills the Solar System, which the Sun’s magnetic field plays an important role in creating.

    Principal Investigator Professor Tim Horbury from the Department of Physics at Imperial said: “We live inside a bubble blown by the Sun in interstellar space. The Earth also has its own magnetic field, which creates a cavity in the solar bubble.

    2
    Professor Tim Horbury describes Solar Orbiter’s journey

    “The interaction between the solar wind and Earth’s magnetic field gives us the aurora – the Northern and Southern Lights – but when the solar wind is strong it can also cause problems for our technology, from power grids to satellites.”

    The Sun’s magnetic field is thought to be generated in a similar way to the Earth’s as it rotates, but it is much more dynamic. Every 11 years the polarity reverses, and this pattern is tied to the pattern of sunspots that appear on the Sun’s surface. Sunspots are associated extreme events called solar flares and ejections of the solar material that cause serious problems if they reach Earth.

    By orbiting the Sun and approaching it at a distance of only 50 million kilometres – inside the orbit of Mercury, the closest planet to the Sun – the Imperial team’s magnetometer will be able to get unprecedented information about how the Sun generates its magnetic field and how this plays a role in the solar wind and more extreme events.

    Sensitive subject

    The instrument is made up of two sensors hosted within metal domes; a black box containing electronics, a computer processor and a power supply; and cables to provide power and communications to the sensors.

    3
    Helen O’Brien describes the working of the sensors

    The magnetometer has to be extremely sensitive to detect the magnetic field from the Sun that will reach the spacecraft. Lead engineer Helen O’Brien from the Department of Physics said: “Our instrument is so sensitive, it could measure the magnetic field of an MRI machine from the other side of London.

    “This means, however, that we have to work hard to isolate it from the other instruments on the spacecraft. Metal objects and electrical circuits create small magnetic fields, so we have really strict requirements on the rest of the project – right down to the screws and the paint.”

    The magnetometer also has to survive some extreme conditions, including the intense vibration from the take-off, which will use a NASA Atlas V rocket. An earlier model of the instrument, which was put through rigorous tests designed to exceed the expected conditions, crumbled under the strain.

    4

    O’Brien said: “We mounted the sensors on a ceramic material that barely expands or contracts with temperature changes, so that their relative position to each other is kept stable during the extreme temperature swings the spacecraft will experience. However, this material is quite brittle, and it fell apart in the vibration test.”

    Thickening the material helped to solve the problem, and as a result of rigorous testing many tweaks and improvements have been made to the design. But now, the device is finished, and it is waiting in a clean room at Imperial before it gets mounted onto the spacecraft.

    In the meantime, the team are building a ‘flight spare’ – an identical device just in case something happens to the original before launch. When the instrument is mounted on the spacecraft, the team will be giving extremely precise instructions – down to the material the screwdriver is made out of, and making sure no tiny shavings of metal are left behind, which could disturb the measurements.

    Once all the instruments are mounted, the whole spacecraft will go through another barrage of tests, before being shipped to Cape Canaveral for launch in February 2019. It will then spend two years getting to the Sun, and another eight collecting data. Eventually, its solar panels will degrade and stop producing power but it will drift around the Sun forever.

    See the full article here .

    Please help promote STEM in your local schools.

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    Imperial College London

    Imperial College London is a science-based university with an international reputation for excellence in teaching and research. Consistently rated amongst the world’s best universities, Imperial is committed to developing the next generation of researchers, scientists and academics through collaboration across disciplines. Located in the heart of London, Imperial is a multidisciplinary space for education, research, translation and commercialisation, harnessing science and innovation to tackle global challenges.

     
  • richardmitnick 10:10 am on December 22, 2016 Permalink | Reply
    Tags: , Dr Omar Cedillos-Barraza, Hafnium carbide, ICL-Imperial College London, New record set for world's most heat resistant material   

    From ICL: “New record set for world’s most heat resistant material” 

    Imperial College London
    Imperial College London

    22 December 2016
    Caroline Brogan

    1
    Discovery paves the way for new types of heat shields
    (image: NASA)

    Researchers have discovered that tantalum carbide and hafnium carbide materials can withstand scorching temperatures of nearly 4000 degrees Celsius.

    In particular, the team from Imperial College London discovered that the melting point of hafnium carbide is the highest ever recorded for a material. Being able to withstand temperatures of nearly 4000°C could pave the way for both materials to be used in ever more extreme environments, such as in heat resistant shielding for the next generation of hypersonic space vehicles.

    Tantalum carbide (TaC) and hafnium carbide (HfC) are refractory ceramics, meaning they are extraordinarily resistant to heat. Their ability to withstand extremely harsh environments means that refractory ceramics could be used in thermal protection systems on high-speed vehicles and as fuel cladding in the super-heated environments of nuclear reactors. However, there hasn’t been the technology available to test the melting point of TaC and HfC in the lab to determine how truly extreme an environment they could function in.

    The researchers of the study, which is published in the journal Scientific Reports, developed a new extreme heating technique using lasers to test the heat tolerance of TaC and HfC. They used the laser-heating techniques to find the point at which TaC and HfC melted, both separately and as mixed compositions of both.

    They found that the mixed compound (Ta0.8Hf0.20C) was consistent with previous research, melting at 3905°C, but the two compounds on their own exceeded previous recorded melting points. The compound TaC melted at 3768°C and HfC melted at 3958°C.

    Space race

    The researchers say the new findings could pave the way for the next generation of hypersonic vehicles, meaning spacecraft could become faster than ever.

    Dr Omar Cedillos-Barraza, who is currently an Associate Professor at the University of Texas – El Paso, carried out the study while doing his PhD at Imperial’s Department of Materials.

    Dr Cedillos-Barraza said: “The friction involved when travelling above Mach 5 – hypersonic speeds – creates very high temperatures. So far, TaC and HfC have not been potential candidates for hypersonic aircraft, but our new findings show that they can withstand even more heat than we previously thought – more than any other compound known to man. This means that they could be useful materials for new types of spacecraft that can fly through the atmosphere like a plane, before reaching hypersonic speeds to shoot out into space. These materials may enable spacecraft to withstand the extreme heat generated from leaving and re-entering the atmosphere.”

    Examples of potential uses for TaC and HfC could be in nose caps for spacecraft, and as the edges of external instruments that have to withstand the most friction during flight.

    Currently, vehicles going over Mach 5 speeds do not carry people, but Dr Cedillos-Barraza suggests it may be possible in the future.

    Dr Cedillos-Barraza added: “Our tests demonstrate that these materials show real promise in the engineering of space vehicles of the future. Being able to withstand such extreme temperatures means that missions involving hypersonic spacecraft may one day be manned missions. For example, a flight from London to Sydney may take about 50 minutes at Mach 5, which could open a new world of commercial opportunities for countries around the world.”

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

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    Imperial College London

    Imperial College London is a science-based university with an international reputation for excellence in teaching and research. Consistently rated amongst the world’s best universities, Imperial is committed to developing the next generation of researchers, scientists and academics through collaboration across disciplines. Located in the heart of London, Imperial is a multidisciplinary space for education, research, translation and commercialisation, harnessing science and innovation to tackle global challenges.

     
  • richardmitnick 11:47 am on October 17, 2016 Permalink | Reply
    Tags: , , , Dr Michel Della Negra, Dr Peter Jenni, ICL-Imperial College London, Sir Tejinder (Jim) Virdee, W.K.H. Panofsky Prize   

    From ICL: “Fathers of Higgs boson detectors awarded particle physics prize” 

    Imperial College London
    Imperial College London

    17 October 2016
    Hayley Dunning

    1
    Professor Sir Tejinder Virdee (L) and Dr Michel DellaNegra (R)

    2
    Dr Peter Jenni

    Two Imperial physicists share in a prize for experimental physics for their work masterminding the CMS and ATLAS experiments

    The W.K.H. Panofsky Prize in Experimental Particle Physics, awarded by the American Physical Society, has this year been given to three scientists, “For distinguished leadership in the conception, design, and construction of the ATLAS and CMS detectors, which were instrumental in the discovery of the Higgs boson.”

    Receiving the honours are Professor Sir Tejinder (Jim) Virdee FRS from the Department of Physics at Imperial, Dr Michel Della Negra from CERN, who is also a Distinguished Research Fellow at Imperial, and Dr Peter Jenni from CERN and Albert-Ludwigs-University Freiburg.

    In July 2012, scientists using the Compact Muon Solenoid (CMS) and A Toroidal LHC Apparatus (ATLAS) experiments operating at the Large Hadron Collider (LHC) at CERN announced the discovery of the Higgs boson.

    CERN/CMS Detector
    CERN/CMS Detector

    CERN CMS Higgs Event
    CERN CMS Higgs Event

    CERN/ATLAS detector
    CERN/ATLAS detector

    CERN ATLAS Higgs Event
    CERN ATLAS Higgs Event

    This new particle, whose associated field gives mass to the fundamental particles, is the last missing link of the Standard Model of particle physics.

    The Standard Model of elementary particles (more schematic depiction), with the three generations of matter, gauge bosons in the fourth column, and the Higgs boson in the fifth.
    The Standard Model of elementary particles (more schematic depiction), with the three generations of matter, gauge bosons in the fourth column, and the Higgs boson in the fifth

    Professor Jordan Nash, head of the Department of Physics at Imperial, said: “I’m delighted to see that Jim and Michel have been awarded this year’s Panofsky prize. Their dedication for more than two decades to the design, construction, and operation of the CMS detector has been essential to enabling the wonderful science and discoveries we have seen at the LHC.”

    Hayley Dunning talked to Professor Virdee about his latest award, chasing the Higgs and the future of the Large Hadron Collider.

    You’ve won a few prizes for your work – how does it feel to win the W.K.H. Panofsky Prize?

    It is a great honour to receive this prize and it is particularly pleasing to get this recognition from our peers. Even though the past 25 years have been long and not without many difficulties, it has nevertheless led to a fantastic result for all of us at the LHC – the discovery of the Higgs boson.

    This award is also acknowledgement of the huge experimental effort that led to the discovery of the Higgs boson. This wouldn’t have been possible without the contributions of thousands of scientists and engineers from around the world. On a personal note, I have enjoyed the enormous support of my exceptional colleagues at Imperial as well as the many others in the CMS Collaboration.

    What attracted you to particle physics and big experiments like the LHC?

    Particle physics is a modern-day name for the centuries-old effort to understand the fundamental laws of nature. I was intrigued to find out more: how nature really works at the most fundamental level, and I’ve always felt that this has to be one of the most exciting of human endeavours.

    Particle physicists didn’t really set out to do ‘big’ experiments. I, like my colleagues, were not attracted by the magnitude of the experiment, but by the magnitude and importance of the questions for which we were searching answers. CMS has the size it has due to the huge power of its ‘microscope’ to examine physics at the smallest distance scales offered for study by the highest accelerator energy so far achieved.

    And this can be seen in the history of this endeavour: twenty-five years ago, we started CMS with a handful of physicists and engineers. The enormity of the detectors that were necessary to answer these enormous questions meant that the collective talents and resources of a worldwide effort would be necessary. Now, CMS has over 3,000 scientists and engineers and involves 40 countries.

    Did you always believe you would be able to find the Higgs boson with CMS and ATLAS?

    In retrospect, and not overlooking the open mind that we all physicists have to have, I did believe, that if the Higgs boson were a true constituent particle of nature, we would find it sooner or later at the LHC. It has to be remembered that mass is a fundamental attribute of fundamental particles and is what gives our universe substance.

    At the time of conception of the CMS detector, a few of us paid particular attention to conjectures that suggested the mass of the Higgs boson could lie in the range where, years later, in 2012, it was eventually found. In this range the electromagnetic calorimeter, which I pioneered, played a vital role. Similarly, other parts of CMS were conceived, designed and constructed so as to ensure that the Higgs boson would be found if it were at other masses.

    Luckily, it turned out that the Higgs boson is a choice of nature. What was less of a stroke of luck is that we found it – given that it is a real element of nature.

    What are you working on now, and what do you hope for the future of the LHC experiments?

    My current work involves the in-depth study of the properties of the newly found Higgs boson, the search for widely anticipated physics beyond the Standard Model, and the design of the upgrades to the CMS detector for very high luminosity (implying very high proton-proton interaction rate) LHC running, due to start in the mid-2020s.

    In the context of this upgrade, a year or so ago I began another exciting project to develop a novel technique to replace a part of CMS. The goal is to increase the physics reach of the next phase of the LHC and take us into the 2030s. In 2015 I was awarded an EU-ERC Advanced grant to carry out the research, development and prototyping of this novel project.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    Imperial College London

    Imperial College London is a science-based university with an international reputation for excellence in teaching and research. Consistently rated amongst the world’s best universities, Imperial is committed to developing the next generation of researchers, scientists and academics through collaboration across disciplines. Located in the heart of London, Imperial is a multidisciplinary space for education, research, translation and commercialisation, harnessing science and innovation to tackle global challenges.

     
  • richardmitnick 5:30 am on September 10, 2016 Permalink | Reply
    Tags: , , , ICL-Imperial College London,   

    From ICL: “Activity of Huntington’s disease gene curbed for six months in mice” 

    Imperial College London
    Imperial College London

    09 September 2016
    Hayley Dunning

    1
    Healthy brain (L) and Huntington’s brain (R). No image credit.

    A single injection of a new treatment has reduced the activity of the gene responsible for Huntington’s disease for several months in a trial in mice.

    Huntington’s disease is a genetic disorder that affects around 1 in every 10,000 people and damages nerve cells in the brain. This causes neurological symptoms affecting movement, cognition and behaviour.

    Huntington’s usually only begins to show symptoms in adulthood. There is currently no cure and no way to slow the progression of the disease. Symptoms typically progress over 10-25 years until the person eventually dies.

    Now, the EU-funded FINGERS4CURE project team led by researchers at Imperial College London have engineered a therapeutic protein called a ‘zinc finger’.

    Huntington’s disease is caused by a mutant form of a single gene called Huntingtin. The zinc finger protein works by targeting the mutant copies of the Huntingtin gene, repressing its ability to express and create harmful proteins.

    In the new study involving mice, published in the journal Molecular Neurodegeneration, the injection of zinc finger repressed the mutant copies of the gene for at least six months.

    In a previous study in mice, the team had curbed the mutant gene’s activity for just a couple of weeks. By tweaking the ingredients of the zinc finger in the new study they were able to extend its effects to several months, repressing the disease gene over that period without seeing any harmful side effects. This involved making the zinc finger as invisible to the immune system as possible.

    A lot of promise

    Project lead Dr Mark Isalan from the Department of Life Sciences at Imperial said: “We are extremely excited by our latest results, which show a lot of promise for treating Huntington’s disease.

    “However, while these encouraging results in mice mean that the zinc finger looks like a good candidate to take forward to human trials, we still need to do a lot of work first to answer important questions around the safety of the intervention, whether repeat treatments are effective, whether there might be longer-term side effects, and whether we can extend and increase the benefits beyond six months.

    “In this study we weren’t looking at how repressing the gene activity affected the symptoms of the disease and this is obviously a critical question as well. However, we have reason to be confident from our previous studies that repressing the gene does in fact significantly reduce symptoms.

    “If all goes well and we have further positive results, we would aim to start clinical trials within five years to see whether the treatment could be safe and effective in humans. We are urgently looking for industry partners and funding to achieve this.”

    Cut off at the source

    The mutant Huntingtin gene is thought to cause toxic levels of protein to aggregate in the brain. Preventing the activity of this gene could theoretically halt the disease, but this has been difficult to achieve.

    The gene is present in many different cell types in the brain, making it difficult to target, and every patient also has a non-mutant copy of the gene, which scientists need to avoid targeting with any intervention in order to prevent unwanted side effects.

    The zinc finger protein sticks to the DNA of the mutant Huntingtin gene and turns off the gene’s expression. “We don’t know exactly how the mutant Huntingtin gene causes the disease, so the idea is that targeting the gene expression cuts off the problem at its source – preventing it from ever having the potential to act,” said Dr Isalan.

    By targeting the fundamental DNA of the gene, the zinc finger therapy also has the advantage over other potential Huntington’s therapies of needing less frequent treatments.

    Lengthening effect

    In the study, the researchers gave a single injection of zinc finger to 12 mice with Huntingdon’s disease. They examined the brains of the mice at different intervals after the initial injection and found that on average, 77 per cent of the ‘bad’ gene expression was repressed in mouse brains three weeks after injection of the zinc finger, 61 per cent repressed at six weeks, and 48 per cent repressed at 12 weeks.

    By 24 weeks after the initial injections, there was still 23 per cent repression, which is thought to still be useful therapeutically. The team are now working on ways to lengthen the repression period even further.

    The study was funded by a European Research Council Proof-of-Concept Award (ERC-2014-PoC 641232 FINGERS4CURE) and involved researchers from Imperial College London, Centre for Genomi Regulation (CRG) in Spain, and Universitat Pompeu Fabra in Spain.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    Imperial College London

    Imperial College London is a science-based university with an international reputation for excellence in teaching and research. Consistently rated amongst the world’s best universities, Imperial is committed to developing the next generation of researchers, scientists and academics through collaboration across disciplines. Located in the heart of London, Imperial is a multidisciplinary space for education, research, translation and commercialisation, harnessing science and innovation to tackle global challenges.

     
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