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  • richardmitnick 1:44 pm on December 10, 2016 Permalink | Reply
    Tags: , , QCN Quake-Catcher Network   

    From EarthSky: “New Zealand quake reveals new land” 



    December 9, 2016
    Eleanor Imster

    The 7.8-magnitude earthquake off the coast of New Zealand’s South Island on November 13 created a thin swath of newly exposed land. Before and after images.

    Satellite image from a October 12, 2016, a month before the earthquake. Image via NASA

    A satellite image [below] shows a thin swath of land, previously underwater, uplifted by the 7.8 magnitude earthquake that jolted the northeastern coast of New Zealand’s South Island on November 13, 2016. For comparison, see the satellite image [above] which shows that same area of coastline a month before the quake.

    On November 25, 2016, the ESA’s Sentinel 2 satellite captured this image of the newly exposed land near Kaikoura. Image via NASA

    The quake shifted huge quantities of rock and lifted the seabed by 0.5 to 2 meters (2 to 7 feet) along a 20-kilometer (12.4 mile) stretch of the Kaikoura coast. In one area, the uplift was a remarkable 5.5 meters (18 feet).

    On the ground, scientists have encountered some unusual sights as they surveyed the new land by foot and helicopter. Seaweed littered the newly exposed slabs of rock and coral reef. Crayfish, sea snails, and other marine life were left stranded well above the high tide level.

    People living near the Kaikoura coast were struck by the sounds that accompanied the quake as well as the sights. In a GNS Science video (above), geologist Kelvin Berryman said:

    “Locals here described not the earthquake noise but the noise of water running off the top of this uplifted platform. They said that the noise was just horrendous.”

    The new land along the Kaikoura coast is likely there to stay, according to a blog post from the New Zealand hazards monitoring organization GeoNet:

    While beaches raised by earthquakes occasionally sink back down gradually or get pushed down by other earthquakes, the New Zealand coast is full of historical examples of earthquake uplifted land staying put for hundreds to thousands of years.

    Residents look at damage caused by an earthquake, along State Highway One near the town of Ward, New Zealand. Image Anthony Phelps/Reuters via the guardian

    See the full article here .

    Meet The Quake-Catcher Network

    QCN bloc

    Quake-Catcher Network

    The Quake-Catcher Network is a collaborative initiative for developing the world’s largest, low-cost strong-motion seismic network by utilizing sensors in and attached to internet-connected computers. With your help, the Quake-Catcher Network can provide better understanding of earthquakes, give early warning to schools, emergency response systems, and others. The Quake-Catcher Network also provides educational software designed to help teach about earthquakes and earthquake hazards.

    After almost eight years at Stanford, and a year at CalTech, the QCN project is moving to the University of Southern California Dept. of Earth Sciences. QCN will be sponsored by the Incorporated Research Institutions for Seismology (IRIS) and the Southern California Earthquake Center (SCEC).

    The Quake-Catcher Network is a distributed computing network that links volunteer hosted computers into a real-time motion sensing network. QCN is one of many scientific computing projects that runs on the world-renowned distributed computing platform Berkeley Open Infrastructure for Network Computing (BOINC).

    The volunteer computers monitor vibrational sensors called MEMS accelerometers, and digitally transmit “triggers” to QCN’s servers whenever strong new motions are observed. QCN’s servers sift through these signals, and determine which ones represent earthquakes, and which ones represent cultural noise (like doors slamming, or trucks driving by).

    There are two categories of sensors used by QCN: 1) internal mobile device sensors, and 2) external USB sensors.

    Mobile Devices: MEMS sensors are often included in laptops, games, cell phones, and other electronic devices for hardware protection, navigation, and game control. When these devices are still and connected to QCN, QCN software monitors the internal accelerometer for strong new shaking. Unfortunately, these devices are rarely secured to the floor, so they may bounce around when a large earthquake occurs. While this is less than ideal for characterizing the regional ground shaking, many such sensors can still provide useful information about earthquake locations and magnitudes.

    USB Sensors: MEMS sensors can be mounted to the floor and connected to a desktop computer via a USB cable. These sensors have several advantages over mobile device sensors. 1) By mounting them to the floor, they measure more reliable shaking than mobile devices. 2) These sensors typically have lower noise and better resolution of 3D motion. 3) Desktops are often left on and do not move. 4) The USB sensor is physically removed from the game, phone, or laptop, so human interaction with the device doesn’t reduce the sensors’ performance. 5) USB sensors can be aligned to North, so we know what direction the horizontal “X” and “Y” axes correspond to.

    If you are a science teacher at a K-12 school, please apply for a free USB sensor and accompanying QCN software. QCN has been able to purchase sensors to donate to schools in need. If you are interested in donating to the program or requesting a sensor, click here.

    BOINC is a leader in the field(s) of Distributed Computing, Grid Computing and Citizen Cyberscience.BOINC is more properly the Berkeley Open Infrastructure for Network Computing, developed at UC Berkeley.

    Earthquake safety is a responsibility shared by billions worldwide. The Quake-Catcher Network (QCN) provides software so that individuals can join together to improve earthquake monitoring, earthquake awareness, and the science of earthquakes. The Quake-Catcher Network (QCN) links existing networked laptops and desktops in hopes to form the worlds largest strong-motion seismic network.

    Below, the QCN Quake Catcher Network map
    QCN Quake Catcher Network map

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  • richardmitnick 1:20 pm on December 10, 2016 Permalink | Reply
    Tags: , , , L2 Puppis, Will Earth still exist 5 billion years from now?   

    From “Will Earth still exist 5 billion years from now?” 

    Astrobiology Magazine

    Astrobiology Magazine

    Dec 9, 2016
    No writer credit found

    Composite view of L2 Puppis in visible light | © P. Kervella et al. (CNRS/U. de Chile/Observatoire de Paris/LESIA/ESO/ALMA)

    What will happen to Earth when, in a few billion years’ time, the Sun is a hundred times bigger than it is today? Using the most powerful radio telescope in the world, an international team of astronomers has set out to look for answers in the star L2 Puppis.

    L2 Puppis

    Five billion years ago, this star was very similar to the Sun as it is today.

    “Five billion years from now, the Sun will have grown into a red giant star, more than a hundred times larger than its current size,” says Professor Leen Decin from the KU Leuven Institute of Astronomy. “It will also experience an intense mass loss through a very strong stellar wind. The end product of its evolution, 7 billion years from now, will be a tiny white dwarf star. This will be about the size of the Earth, but much heavier: one tea spoon of white dwarf material weighs about 5 tons.”

    This metamorphosis will have a dramatic impact on the planets of our Solar System. Mercury and Venus, for instance, will be engulfed in the giant star and destroyed.

    “But the fate of the Earth is still uncertain,” continues Decin. “We already know that our Sun will be bigger and brighter, so that it will probably destroy any form of life on our planet. But will the Earth’s rocky core survive the red giant phase and continue orbiting the white dwarf?”

    ALMA is the world’s largest observatory at millimetre wavelengths. It is installed on the high-altitude plateau of Chajnantor in the Atacama desert (Chile). It consists of 66 individual radio antennas used jointly to synthesize a giant virtual telescope of 16 km in diameter. Credit: ALMA (ESO/NAOJ/NRAO)

    To answer this question, an international team of astronomers observed the evolved star L2 Puppis. This star is 208 light years away from Earth – which, in astronomy terms, means nearby. The researchers used the ALMA radio telescope, which consists of 66 individual radio antennas that together form a giant virtual telescope with a 16-kilometre diameter.

    “We discovered that L2 Puppis is about 10 billion years old,” says Ward Homan from the KU Leuven Institute of Astronomy. “Five billion years ago, the star was an almost perfect twin of our Sun as it is today, with the same mass. One third of this mass was lost during the evolution of the star. The same will happen with our Sun in the very distant future.”

    300 million kilometres from L2 Puppis – or twice the distance between the Sun and the Earth – the researchers detected an object orbiting the giant star. In all likelihood, this is a planet that offers a unique preview of our Earth five billion years from now.

    A deeper understanding of the interactions between L2 Puppis and its planet will yield valuable information on the final evolution of the Sun and its impact on the planets in our Solar System. Whether the Earth will eventually survive the Sun or be destroyed is still uncertain. L2 Puppis may be the key to answering this question.

    See the full article here .

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  • richardmitnick 1:03 pm on December 10, 2016 Permalink | Reply  

    From BNL: “Scientists Track Chemical and Structural Evolution of Catalytic Nanoparticles in 3D” 

    Brookhaven Lab

    December 8, 2016
    Karen McNulty Walsh
    (631) 344-8350
    Peter Genzer
    (631) 344-3174

    Huolin Xin of Brookhaven Lab’s Center for Functional Nanomaterials with a sample holder in front of the electron microscope his team used to track the chemical and structural evolution of catalytic nanoparticles in 3D.

    Catalysts are at the heart of fuel cells—devices that convert hydrogen and oxygen to water and enough electricity to power vehicles for hundreds of miles. But finding effective, inexpensive catalysts has been a key challenge to getting more of these hydrogen-powered, emission-free vehicles out on the road.

    To help tackle this challenge, scientists at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory used a high-resolution electron microscope to study nanoscale details of catalytic particles made of nickel and cobalt—inexpensive alternatives to the costly platinum used in most fuel cells today. A paper describing the research in the journal Nature Communications includes 3D, dynamic images that reveal how the particles’ external and internal structure and chemical makeup change as they become catalytically active. Understanding these nanoscale structural and chemical features will help scientists learn what characteristics make the inexpensive particles most effective—and devise ways to optimize their performance.

    Access mp4 video here .

    Swiss-cheese surface area

    One of the most important characteristics of a catalyst is having a high surface area compared to its volume. “Reactions happen on the surface,” explained Huolin Xin, who led the work at Brookhaven’s Center for Functional Nanomaterials (CFN). The more surface area there is, the higher the reactivity.

    Tiny nanoparticles naturally have a large surface-to-volume ratio. However, the imaging techniques Xin and colleagues used to study the bimetallic nickel-and-cobalt particles revealed that these nanoparticles increase their surface area in an additional, unique way.

    A comparison of two different oxidation results in nickel-cobalt nanoparticles. While a small percentage of the particles form hollow spheres (top), the vast majority form a porous Swiss-cheese-like structure (bottom) that has much greater surface area for the same volume.

    The transformation happens when the nanoparticles are oxidized. Instead of forming a metal oxide shell enclosing a single void in the center—as single-metal materials such as nickel and cobalt do—the bimetallic particles developed an extremely porous “Swiss cheese” like structure that was no longer hollow, Xin said.

    “This is the first time anyone has shown how a bi-metallic material forms these Swiss cheese structures,” Xin said.

    Because the porous structure has a higher “packing density”—meaning more reactive material is packed into a smaller space than in hollow nanoparticles—it should result in higher catalytic activity, Xin said. The porous particles may also make stronger structures, which would be particularly useful in applications where mechanical specifications exclude weaker hollow structures, such as batteries.

    Imaging the nanoscale details

    Revealing the details of how these structures formed, including their chemical makeup, was no simple task. The scientists used chemical-sensitive electron tomography, which is a nanoscale version of a CAT scan, to track what was happening structurally and chemically on the surface and inside the particles in 3D as they were oxidizing. This process occurs as the sample is heated to 500 degrees Celsius.

    “We custom-designed a sample holder that could withstand that change in temperature, while also letting us tilt the sample to scan it from every angle—all within a transmission electron microscope,” Xin said.

    These capabilities are unique to the CFN, a DOE Office of Science User Facility that offers both state-of-the-art instruments and the expertise of scientists like Xin to the entire scientific community through its user program.

    Xin’s team tracked precisely where metal ions were reacting with oxygen to become metal oxides—and discovered that the process takes place in two stages.

    “In the first stage, oxidation occurs only on the surface, with metal ions moving out of the particles to react with the oxygen forming an oxide shell,” Xin said. “In the second stage, however, oxidation starts to happen on the inside of the particles as well, suggesting that oxygen moves in.”

    The scientists suspected that tiny pinholes were created on the particles’ surface as the oxide shell was forming, providing a pathway for the influx of oxygen. A closer look at one partially oxidized particle confirmed this suspicion, showing that as the oxide formed on the surface, it beaded up like droplets on a water-repellent surface, leaving tiny spaces in between.

    The scientists also used “electron energy loss spectroscopy” and the distinct “chemical fingerprints” of nickel and cobalt to track where the individual elements were located within the particles as the oxidation process progressed. This gave them another way to see whether oxygen was finding a way into the particles.

    “We found that cobalt moves preferentially to where the oxygen is,” Xin explained. “This is because cobalt reacts more easily with oxygen than nickel does.”

    Three stages of oxidation of nickel-cobalt nanoparticles. Left: the pristine nickel-cobalt nanoparticle. Middle: an intermediate stage in which the formation of pinholes allows oxygen access to the interior. Right: the Swiss-cheese-like structure with dark areas representing the voids within the particle. Catalytic reactions can occur across the entire surfaces and along the inner surfaces of the pores.

    During early oxidation, cobalt preferentially moved to the exterior of the particles to engage in the formation of the oxide shell. But later-stage scans revealed that the internal surfaces of the Swiss cheese pores were rich in cobalt as well.

    “This supports our previous idea that oxygen is getting inside and pulling the cobalt out to the surface of the internal pores to react,” Xin said.

    This ability to monitor the surface chemistry of nanoparticles, both externally and along the internal curved surfaces of pores, could result in a more rational approach to catalyst design, Xin said.

    “People usually try to just mix particles and create a better catalyst by trial and error. But what really matters is the surface structure. This imaging technology gives us an accurate way to determine the composition of naturally curved surfaces and interfaces to understand why one catalyst will perform better than another.”

    This research was supported by the DOE Office of Science.

    See the full article here .

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    BNL Campus

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world.Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.

  • richardmitnick 7:56 am on December 10, 2016 Permalink | Reply
    Tags: , , , GR740 next-generation microprocessor   

    From ESA: “GR740 next-generation microprocessor” 

    ESA Space For Europe Banner

    European Space Agency


    A close-up of the next-generation microprocessor that will serve a wide variety of future space missions.

    Standard terrestrial chips wouldn’t last very long in orbit under the harsh blast of space radiation. So ESA has had a long history of working with industry on specially ‘rad-hardened’ designs for space.

    This GR740 microprocessor, developed by Cobham Gaisler in Sweden and manufactured by France-based STMicroelectronics, is a quadcore design combining four embedded LEON4 cores. The LEON4 is the latest member of a series of chips that began with the LEON2-FT, developed at ESA from the second half of the 1990s.

    See the full article here .

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    The European Space Agency (ESA), established in 1975, is an intergovernmental organization dedicated to the exploration of space, currently with 19 member states. Headquartered in Paris, ESA has a staff of more than 2,000. ESA’s space flight program includes human spaceflight, mainly through the participation in the International Space Station program, the launch and operations of unmanned exploration missions to other planets and the Moon, Earth observation, science, telecommunication as well as maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana, and designing launch vehicles. ESA science missions are based at ESTEC in Noordwijk, Netherlands, Earth Observation missions at ESRIN in Frascati, Italy, ESA Mission Control (ESOC) is in Darmstadt, Germany, the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany, and the European Space Astronomy Centre is located in Villanueva de la Cañada, Spain.

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  • richardmitnick 7:41 am on December 10, 2016 Permalink | Reply
    Tags: , , , Could Flaring Stars Change Our Views of Their Planets?, , Stellar flares   

    From AAS NOVA: “Could Flaring Stars Change Our Views of Their Planets?” 


    American Astronomical Society

    9 December 2016
    Susanna Kohler

    Artist’s illustration of an exoplanet being hit by a powerful eruption from its host star. A new study suggests that flare impacts could alter the measurements we make of exoplanet atmospheres. [NASA]

    As the exoplanet count continues to increase, we are making progressively more measurements of exoplanets’ outer atmospheres through spectroscopy. A new study, however, reveals that these measurements may be influenced by the planets’ hosts.

    Spectra From Transits

    Exoplanet spectra taken as they transit their hosts can tell us about the chemical compositions of their atmospheres. Detailed spectroscopic measurements of planet atmospheres should become even more common with the next generation of missions, such as the James Webb Space Telescope (JWST), or Planetary Transits and Oscillations of Stars (PLATO).

    NASA/ESA/CSA Webb Telescope annotated
    NASA/ESA/CSA Webb Telescope annotated


    But is the spectrum that we measure in the brief moment of a planet’s transit necessarily representative of its spectrum all of the time? A team of scientists led by Olivia Venot (University of Leuven in Belgium) argue that it might not be, due to the influence of the planet’s stellar host.

    Atmospheric composition of a planet before flare impacts (dotted lines), during the steady state reached after a flare impact (dashed lines), and during the steady state reached after a second flare impact (solid lines). [Venot et al. 2016]

    The team suggests that when a host’s flares impact upon a planet’s atmosphere (especially likely in the case of active M-dwarfs that commonly harbor planetary systems), this activity may modify the chemical composition of the planet’s atmosphere. This would in turn alter the spectrum that we measure from the exoplanet.

    Modeling Atmospheres

    Venot and collaborators set out to test the effect of stellar flares on exoplanet atmospheres by modeling the atmospheres of two hypothetical planets orbiting the star AD Leo — an active and flaring M dwarf located roughly 16 light-years away — at two different distances. The team then examined what happened to the atmospheres, and to the resulting spectra that we would observe, when they were hit with a stellar flare typical of AD Leo.

    The difference in relative absorption between the initial steady-state and the instantaneous transmission spectra, obtained during the different phases of the flare. The left plot examines the impulsive and gradual phases, when the flare first impacts and then starts to pass. The peak photon flux occurs at 912 seconds. The right plot examines the return to a steady state over 1012 seconds, or roughly ~30,000 years. [Adapted from Venot et al. 2016]

    The authors found that the planets’ atmospheric compositions were significantly affected by the incoming stellar flare. The sudden increase in incoming photon flux changed the chemical abundances of several important molecular species, like hydrogen and ammonia — which resulted in changes to the spectrum that would be observed during the planet’s transit.

    Permanent Impact

    In addition to demonstrating that a planet’s atmospheric composition changes during and immediately after a flare impact, Venot and collaborators show that the chemical alteration isn’t temporary: the planet’s atmosphere doesn’t fully return to its original state after the flare passes. Instead, the authors find that it settles to a new steady-state composition that can be significantly different from the pre-flare composition.

    For a planet that is repeatedly hit by stellar flares, therefore, its atmospheric composition never actually settles to a steady state. Instead it is continually and permanently modified by its host’s activity.

    Venot and collaborators demonstrate that the variations of planetary spectra due to stellar flares should be easily detectable by future missions like JWST. We must therefore be careful about the conclusions we draw about planetary atmospheres from measurements of their spectra.


    Olivia Venot et al 2016 ApJ 830 77. doi:10.3847/0004-637X/830/2/77

    See the full article here .

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  • richardmitnick 7:22 am on December 10, 2016 Permalink | Reply
    Tags: , , , , , , SESAME Synchrotron,   

    From Symmetry: “SESAME to open in 2017” 

    Symmetry Mag


    Troy Rummler

    The first synchrotron radiation source in the Middle East is running tests before its planned 2017 start.

    SESAME Particle Accelerator Jordan interior. Noemi Caraban, SESAME

    SESAME (Synchrotron-light for Experimental Science and Applications in the Middle East) campus

    Scientists and engineers at the first synchrotron radiation source in the Middle East have begun commissioning, a major milestone before officially starting operations in 2017.

    When fully operational, the facility in Allan, Jordan, called SESAME, will mark a major victory for science in the region and also for its international backers. Like CERN, SESAME was established under the auspices of UNESCO, but it is now an independent intergovernmental organization and aims to facilitate peace through scientific collaboration that might supersede political divisions. Countries and labs the world over have responded to that vision by contributing to SESAME’s design, instrumentation and construction.

    SESAME, which stands for The Synchrotron-light for Experimental Science and Applications in the Middle East, is a 133-meter circumference storage ring built to produce intense radiation ranging from infrared to X-rays, given off by electrons circling inside it at high energies. At the heart of SESAME are injector components from BESSY I, a Berlin-based synchrotron that was decommissioned in 1999, donated to SESAME and upgraded to support a completely new 2.5-GeV storage ring. With funding provided in part by the European Commission and construction led by CERN in collaboration with SESAME, the new ring is on par with most modern synchrotrons.

    Now that the machine is largely complete, technicians can perform quality testing before researchers gain access and determine whether the light source can accomplish its scientific mission.

    “The first scientific mission of SESAME is to promote excellence in science in the Middle East,” says Zehra Sayers, chair of SESAME’s scientific committee and also a faculty member at Sabanci University in Istanbul, Turkey.

    Over the past decade, SESAME has organized regular users meetings each year to discuss and develop proposed research plans. That community is now over 200 strong. The international facility hosts members from Bahrain, Cyprus, Egypt, Iran, Israel, Jordan, Pakistan, the Palestinian Authority and Turkey.

    14th SESAME users’ meeting. Noemi Caraban, SESAME.

    “It is very important for us to be able to perform high quality science at SESAME,” Sayers says. “Because that is what will make it viable, only then people will want to come here to do experiments, and only then people will think that this is really where they can find answers to their questions.”

    Dozens of synchrotrons in other locations throughout the world have already proven themselves as research hubs. Synchrotrons create ultra-bright light radiation and channel it into instruments used for advanced imaging research, with applications ranging from materials science to drug discovery.

    No synchrotrons existed in the Middle East until now. Political turbulence can make access to other facilities abroad challenging. Sayers says she is confident that SESAME will fill the need for a local laboratory.

    The new facility creates an opportunity for regional scientists to collaborate, for example, to study shared cultural heritage. The SESAME light source will be used to identify materials in ancient, cultural artifacts such as textiles and dyes, parchments and inks, and could reveal new information about how the materials were originally prepared.

    Researchers will initially have access to two beamlines of different wavelengths when operations begin. The facility has capacity for 25 beamlines, and it is expected that within a year two more beamlines will become available. As beamlines are added, the number of applications will grow to encompass diverse fields such as archeology, molecular biology, materials science and environmental science.

    The potential diversity is one of SESAME’s greatest strengths, says Maher Attal, who is coordinating the commissioning process. Twelve straight sections of the machine have the capacity for installing insertion devices, series of small dipole magnets that tune the spectrum of the emitted synchrotron light. This makes SESAME a “third generation” light source. SESAME’s materials science beamline, which will come into operation in 2017 or 2018 will be the first to be supplied with light from such a device.

    SESAME is undergoing a period of testing and quality control that usually takes several months. After technicians install and test the individual components, they will guide the beam through the whole machine at low energy to allow scientists to perfect its alignment, then to make measurements and corrections if its performance deviates too far from predicted values. The machine then must pass the same inspections at its maximum energy before the synchrotron officially opens.

    “We expect to deliver the first photon beam to the users in April 2017,” Attal says.

    Scientists will be watching and waiting.

    “We owe it to the region to make SESAME a success,” Sayers says. “It will be a ray of hope in a time of turmoil.”

    See the full article here .

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    Symmetry is a joint Fermilab/SLAC publication.

  • richardmitnick 9:27 pm on December 9, 2016 Permalink | Reply
    Tags: Cyclotrons, , Janet Conrad, , , , ,   

    From Quanta: Women in STEM – “On a Hunt for a Ghost of a Particle” Janet Conrad 

    Quanta Magazine
    Quanta Magazine

    Janet Conrad has a plan to catch the sterile neutrino — an elusive particle, possibly glimpsed by a number of experiments, that would upend what we know about the subatomic world.

    December 8, 2016
    Maggie McKee

    Kayana Szymczak for Quanta Magazine

    Even for a particle physicist, Janet Conrad thinks small. Early in her career, when her peers were fanning out in search of the top quark, now known to be the heaviest elementary particle, she broke ranks to seek out the neutrino, the lightest.

    In part, she did this to avoid working as part of a large collaboration, demonstrating an independent streak shared by the particles she studies. Neutrinos eschew the strong and electromagnetic forces, maintaining only the most tenuous of ties to the rest of the universe through the weak force and gravity. This aloofness makes neutrinos hard to study, but it also allows them to serve as potential indicators of forces or particles entirely new to physics, according to Conrad, a professor at the Massachusetts Institute of Technology. “If there’s a force out there we haven’t seen, it must be because it is very, very weak — very quiet. So looking at a place where things are only whispering is a good idea.”

    In fact, neutrinos have already hinted at the existence of a new type of whispery particle. Neutrinos come in three flavors, morphing from one flavor to another by means of some quantum jujitsu. In 1995, the Liquid Scintillator Neutrino Detector (LSND) at Los Alamos National Laboratory suggested that these oscillations involve more than the three flavors “we knew and loved,” Conrad said. Could there be another, more elusive type of “sterile” neutrino that can’t feel even the weak force? Conrad has been trying to find out ever since, and she expects to get the latest result from a long-running follow-up experiment called MiniBooNE within a year.


    Still, even MiniBooNE is unlikely to settle the question, especially since a number of other experiments have found no signs of sterile neutrinos. So Conrad is designing what she hopes will be a decisive test using — naturally — a small particle accelerator called a cyclotron rather than a behemoth like the Large Hadron Collider in Europe. “I feel like my field just keeps deciding to get at our problems by growing, and I think that there’s going to be a point at which that’s not sustainable,” Conrad said. “When the great meteor hits, I want to be a small, fuzzy mammal. That’s my plan: small, fuzzy mammal.”

    Quanta Magazine spoke with Conrad about her hunt for sterile neutrinos, her penchant for anthropomorphizing particles, and her work on the latest Ghostbusters reboot. An edited and condensed version of the interview follows.

    QUANTA MAGAZINE: What would it mean for physics if sterile neutrinos exist?

    JANET CONRAD: The Standard Model of particle physics has done very well in predicting what’s going on, but there’s a great deal it can’t explain — for example, dark matter.

    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.

    Right now we’re desperately looking for clues as to what the larger theory would be. We have been working on ideas, and in many of these “grand unified theories,” you actually get sterile neutrinos falling out of the theory. If we were to discover that there were these extra neutrinos, it would be huge. It would really be a major clue to what the larger theory would be.

    You’ve been looking for neutrinos your entire career. Was that always the plan?

    I started out thinking I was going to be an astronomer. I went to Swarthmore College and discovered that astronomy is cold and dark. I was lucky enough to get hired to work in a particle physics lab. I worked for the Harvard Cyclotron, which was at that time treating eye cancers. But in the evenings physicists would bring their detectors down and calibrate them using the same accelerator. I was really interested in what they were doing and got a position the next summer at Fermilab [FNAL]. It was such a good fit for me. I just think the idea of creating these tiny little universes is so wondrous. Every collision is a little world. And the detectors are really big and fun to work on — I like to climb around stuff. I liked the juxtaposition of the scales; this incredibly tiny little world you create and this enormous detector you see it in.

    And how did you get into neutrino research in particular?

    When I was in grad school, the big question was: What is the mass of the top quark? Everybody expected me to join one of the collider experiments to find the top quark and measure its mass, and instead I was looking around and was quite interested in what was going on in the neutrino world. I actually had some senior people tell me it would be the end of my career.

    Why did you take that risk?

    I was very interested in the questions that were coming out of the neutrino experiments, and also I didn’t really want to join an enormously large collaboration. I was more interested in the funny little anomalies that were already showing up in the neutrino world than I was in a particle which had to exist — the top quark — and the question of what was its precise mass. I am really, I suppose, an anomaly chaser. I admit it. Some people might call it an epithet. I wear it with pride.

    One of those anomalies was the hint of an extra type of neutrino beyond the three known flavors in the Standard Model. That result from LSND was such an outlier that some physicists suggested dismissing it. Instead, you helped lead an experiment at Fermilab, called MiniBooNE, to follow up on it. Why?

    You’re not allowed to throw out data, I’m sorry. That is exactly how to miss important new physics. We can’t be so in love with our Standard Model that we aren’t willing to question it. Even if the question doesn’t align with our prejudices, we have to ask the question anyway. When I started out, nobody was really interested in sterile neutrinos. It was a lonely land out there.

    MiniBooNE’s results have added to the mystery. In one set of experiments using antineutrinos, it found LSND-like hints of sterile neutrinos, and in another, using neutrinos, it did not.

    The antineutrino result matched up with LSND very well, but the neutrino result, which is the one we produced first, is the one that doesn’t match up. The whole world would be a very different place if we had started with antineutrino running and gotten a result that matched LSND. I think there would have been a lot more interest immediately in the sterile-neutrino question. We would have been where we are now at least 10 years earlier.

    Where are we now?

    There are eight experiments total that have anomalies suggesting the presence of more than the three known flavors of neutrino. There are also seven experiments that don’t. Recently, some of the experiments that have not seen an effect have gotten a lot of press, including IceCube, which is a result that my group worked on. A lot of press came out about how IceCube didn’t see a sterile-neutrino signal. But while the data rules out some of the possible sterile-neutrino masses, it doesn’t rule out all of them, a result we point out in an article that has just been published in Physical Review Letters.

    Why are neutrino studies so hard?

    Most neutrino experiments need very large detectors that need to be underground, almost always under mountains, to be protected from cosmic rays that themselves produce neutrinos. And all of the accelerator systems we build tend to be in plains — like Fermilab is in Illinois. So once you decide you’re going to build a beam and shoot it for such a long distance, the costs are enormous, and the beams are very difficult to design and produce.


    FNAL/NOvA experiment

    Is there any way around these problems?

    What I would really like to see is a future series of experiments that are really decisive. One possibility for this is IsoDAR, which is part of a larger experiment called DAEδALUS.


    IsoDAR will take a small cyclotron and use it as a driver to produce lithium-8 that decays, resulting in a very pure source of antielectron neutrinos. If we paired that with the KamLAND detector in Japan, then you would be able to see the whole neutrino oscillation.

    KamLAND at the Kamioka Observatory in Japan
    KamLAND at the Kamioka Observatory in Japan

    You don’t just measure an effect at a few points, you can trace the entire oscillation wave. The National Science Foundation has given us a little over $1 million to demonstrate the system can work. We’re excited about that.

    Why would IsoDAR be a more decisive sterile-neutrino hunter?

    This is a case where you don’t produce a beam in the normal way, by smashing protons into a target and using a series of magnetic fields to herd the resulting charged particles into a wide beam where they decay into several kinds of neutrinos, among other particles. Instead you allow the particle you produce, which has a short lifetime, to decay. And it decays uniformly into one kind of neutrino in all directions. All of the aspects of this neutrino beam — the flavor, the intensity, the energies — are driven by the interaction that’s involved in the decay, not by anything that human beings do. Human beings cannot screw up this beam! It’s really a new way of thinking and a new kind of source for the neutrino community that I think can become very widely used once we prove the first one.

    So the resulting neutrino interactions are easier to interpret?

    We’re talking about a signal-to-background ratio of 10 to one. By contrast, most of the reactor experiments looking for antineutrinos are running with a signal-to-background ratio of one to one if they do well, since the neutrons that come out of the reactor core can actually produce a signal that looks a lot like the antineutrino signal you are looking for.

    Speaking of spectral signals, tell me about your connection with the recent Ghostbusters movie remake.

    It’s the first movie I’ve consulted for. It happened because of Lindley Winslow. She was at the University of California, Los Angeles, before she came to MIT. At UCLA, she had made a certain amount of connection with the film industry, and so they had gotten in touch with her. She showed them my office, and they really liked my books. My books are stars — you do get to see them in the movie and some of the other things from my office here and there. When they brought the books back, they put them all back exactly the way they were. What’s really funny about that was that they were not in any order.

    What did you think of the movie itself? Did you relate to the way Kristen Wiig played a physicist?

    I was really happy to see a whole new rendering of it. To watch the characters interact; I think there was a lot of impromptu work. It really came through that these women resonated with each other. In the movie, Kristen Wiig goes into an empty auditorium and she rehearses for her lecture. I felt for that character. When I started out as a faculty member, I had very little experience as somebody who actually taught — I had done all this research. It’s kind of ridiculous to think about now, but I went through those first lectures and really rehearsed them.

    In a way, your career has come full circle, since you started out working at a cyclotron in college and now you want to use another one to hunt for sterile neutrinos. Can you really do cutting-edge research with cyclotrons that accelerate particles to energies just a thousandth of a percent of those reached at the Large Hadron Collider?

    Cyclotrons were invented back at the beginning of the last century.

    The prototype cyclotrons built by E.O. Lawrence. On display at the Lawrence Hall of Science. Picture by Deb McCaffrey.

    They were limited in energy, and as a result, they went out of fashion as particle physicists decided that they needed larger and larger accelerators going up to higher and higher energies. But in the meantime, the research that was done for the nuclear physics community and also for medical isotopes and for treating people with cancer took cyclotrons in a whole different direction. They’ve turned into these amazing machines, which now we can bring back to particle physics. There are questions that can perhaps be better answered if you are working at lower energies but with much purer beams, with more intense beams, and with much better-understood beams. And they’re really nice because they’re small. You can bring your cyclotron to your ultra-large detector, whereas it’s very hard to move Fermilab to your ultra-large detector.

    A single type of sterile neutrino is hard to reconcile with existing experiments, right?

    I think the little beast looks different from what we thought. The very simplistic model introduces only one sterile neutrino. That would be a little weird if you were guided by patterns. If you look at the patterns of all the other particles, they’re appearing in sets of three. If you introduce three, and you do all the dynamics between them properly, does that fix the problem? People have taken a few steps toward answering that, but we’re still doing approximations.

    You just called the sterile neutrino a “little beast.” Do you anthropomorphize particles?

    There’s no question about that. They all have these great little personalities. The quarks are the mean girls. They’re stuck in their little cliques and they won’t come out. The electron is the girl next door. She’s the one you can always depend on to be your friend — you plug in and there she is, right? And she’s much more interesting than people would think. What I like about the neutrinos is they’re very independent. With that said, with neutrinos as friends, you will never be lonely, because there are a billion neutrinos in every cubic meter of space. I have opinions about all of them.

    When did you start creating these characterizations?

    I’ve always thought about them that way. I have in fact been criticized for thinking about them that way and I don’t care. I don’t know how you think about things that are disconnected from your own experience. You have to be really careful not to go down a route that you shouldn’t go down, but it’s a way of thinking about things that’s completely legitimate and gives you some context. I still remember once describing some of the work I was doing as fun. I had one physicist say to me, “This is not fun; this is serious research.” I was, like, you know, serious research can be a lot of fun. Being fun doesn’t make it less important — those are not mutually exclusive.

    See the full article here .

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    Formerly known as Simons Science News, Quanta Magazine is an editorially independent online publication launched by the Simons Foundation to enhance public understanding of science. Why Quanta? Albert Einstein called photons “quanta of light.” Our goal is to “illuminate science.” At Quanta Magazine, scientific accuracy is every bit as important as telling a good story. All of our articles are meticulously researched, reported, edited, copy-edited and fact-checked.

  • richardmitnick 8:43 pm on December 9, 2016 Permalink | Reply
    Tags: , , , , , , , , Simons Observatory   

    From LBNL: “$40M to Establish New Observatory Probing Early Universe” 

    Berkeley Logo

    Berkeley Lab

    May 12, 2016 [OMG, where has this been?]
    No writer credit found

    The Simons Array will be located in Chile’s High Atacama Desert, at an elevation of about 17,000 feet. The site currently hosts the Atacama Cosmology Telescope (bowl-shaped structure at upper right) and the Simons Array (the three telescopes at bottom left, center and right). The Simons Observatory will merge these two experiments, add several new telescopes and set the stage for a next-generation experiment. (Credit: University of Pennsylvania)

    The Simons Foundation has given $38.4 million to establish a new astronomy facility in Chile’s Atacama Desert, adding new telescopes and detectors alongside existing instruments in order to boost ongoing studies of the evolution of the universe, from its earliest moments to today. The Heising-Simons Foundation is providing an additional $1.7 million for the project.

    The Simons Observatory is a collaboration among the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab); UC Berkeley; Princeton University; the University of California at San Diego; and University of Pennsylvania, all of which are also providing financial support.

    The observatory will probe the subtle properties of the universe’s first light, known as cosmic microwave background (CMB) radiation.

    CMB per ESA/Planck
    CMB per ESA/Planck


    The observatory will pay particular attention to the polarization, or directional information, in the CMB light to better understand what took place a fraction of a second after the Big Bang. While these events are hidden from view behind the glare of the microwave radiation, the disturbances they caused in the fabric of space-time affected the microwave’s polarization, and scientists hope to work backwards from these measurements to test theories about how the universe came into existence.

    “The Simons Observatory will allow us to peer behind the dust in our galaxy and search for a true signal from the Big Bang,” said Adrian Lee, a physicist at Berkeley Lab, a UC Berkeley physics professor and one of the lead investigators at the observatory.

    A key goal of the project is to detect gravitational waves generated by cosmic inflation, an extraordinarily rapid expansion of space that, according to the most popular cosmological theory, took place in an instant after the Big Bang. These primordial gravitational waves induced a very small but characteristic polarization pattern, called B-mode polarization, in the microwave background radiation that can be detected by telescopes and cameras like those planned for the Simons Observatory.

    B-mode polarization Image: BICEP2 Collaboration

    The Milky Way’s galactic plane rises above the Atacama Cosmology Telescope. The Simons Observatory is planned at the same site in Chile’s High Atacama Desert and will merge existing experiments and add new telescopes and detectors. (Credit: Jon Ward/University of Pennsylvania)

    “While patterns that we see in the microwave sky are a picture of the structure of the universe 380,000 years after the Big Bang, we believe that some of these patterns were generated much earlier, by gravitational waves produced in the first moments of the universe’s expansion,” said project spokesperson Mark Devlin, a cosmologist at the University of Pennsylvania who leads the university’s team in the collaboration. “By measuring how the gravitational waves affect electrons and matter 380,000 years after the Big Bang we are observing fossils from the very, very early universe.”

    Lee added, “Once we see the signal of inflation, it will be the beginning of a whole new era of cosmology.” We will then be looking at a time when the energy scale in the universe was a trillion times higher than the energy accessible in any particle accelerator on Earth.

    By measuring how radiation from the early universe changed as it traveled through space to Earth, the observatory also will teach us about the nature of dark energy and dark matter, the properties of neutrinos and how large-scale structure formed as the universe expanded and evolved.

    Primordial gravitational waves

    Princeton ACT new ,  on Cerro Toco in the Atacama Desert in the north of Chile, near the Llano de Chajnantor Observatory.
    Princeton ACT, on Cerro Toco in the Atacama Desert in the north of Chile, near the Llano de Chajnantor Observatory, pictured here, will merge with another set of instruments, the Simons Array, and new telescopes and equipment will be added at the site with the launch of the Simons Observatory project. (Credit: Princeton University)

    Two existing instruments at the site—the Atacama Cosmology Telescope and the Simons Array—are currently measuring this polarization. The foundation funds will merge these two experiments, expand the search and develop new technology for a fourth-stage, next-generation project—dubbed CMB-Stage 4 or CMB-S4—that could conceivably mine all the cosmological information in the cosmic microwave background fluctuations possible from a ground-based observatory.

    LBL The Simons Array in the Atacama in Chile, with the  Atacama Cosmology Telescope
    LBL The Simons Array in the Atacama in Chile, with the Atacama Cosmology Telescope, on Cerro Toco in the Atacama Desert in the north of Chile, near the Llano de Chajnantor Observatory.

    “We are still in the planning stage for CMB-S4, and this is a wonderful opportunity for the foundations to create a seed for the ultimate experiment,” said Akito Kusaka, a Berkeley Lab physicist and one of the lead investigators. “This gets us off to a quick start.”

    The Simons Observatory is designed to be a first step toward CMB-S4. This next-generation experiment builds on years of support from the National Science Foundation (NSF), and the Department of Energy (DOE) Office of Science has announced its intent to participate in CMB-S4, following the recommendation by its particle physics project prioritization panel. Such a project is envisioned to have telescopes at multiple sites and draw together a broad community of experts from the U.S. and abroad. The Atacama site in Chile has already been identified as an excellent location for CMB-S4, and the Simons Foundation funding will help develop it for that role.

    “We are hopeful that CMB-S4 would shed light not only on inflation, but also on the dark elements of the universe: neutrinos and so-called dark energy and dark matter,” Kusaka said. “The nature of these invisible elements is among the biggest questions in particle physics as well.”

    Beyond POLARBEAR

    Experiments at the Chilean site have already paved the way for CMB-S4. A 2012 UC Berkeley-led experiment with participation by Berkeley Lab researchers, called POLARBEAR, used a 3.5-meter telescope at the Chilean site to measure the gravitational-lensing-generated B-mode polarization of the cosmic microwave background radiation.

    POLARBEAR McGill Telescope located in the Atacama Desert of northern Chile in the Antofagasta Region. The POLARBEAR experiment is mounted on the Huan Tran Telescope (HTT) at the James Ax Observatory in the Chajnantor Science Reserve.
    The POLARBEAR experiment is mounted on the Huan Tran Telescope (HTT) at the James Ax Observatory in the Chajnantor Science Reserve.

    Team scientists confirmed in 2014 that the signal was strong enough to allow them eventually to measure the neutrino mass and the evolution of dark energy.

    The recent addition of two more telescopes upgrades POLARBEAR to the Simons Array, which will speed up the mapping of the CMB and improve sky and frequency coverage. The $40 million in new funding will make possible the successor to the Simons Array and the nearby Atacama Cosmology Telescope.

    Current stage-3 experiments for these short-wavelength microwaves, which must be chilled to three-tenths of a degree Kelvin above absolute zero, have about 10,000 pixels, Lee said.

    “We need to make a leap in our technology to pave the way for the 500,000 detectors required for the ultimate experiment,” he said. “We’ll be generating the blueprint for a much more capable telescope.”

    “The generosity of this award is unprecedented in our field, and will enable a major leap in scientific capability,” said Brian Keating, leader of the UC San Diego contingent and current project director. “People are used to thinking about mega- or gigapixel detectors in optical telescopes, but for signals in the microwave range 10,000 pixels is a lot. What we’re trying to do—the real revolution here—is to pave the way to increase our pixels number by more than an order of magnitude.”

    Berkeley Lab and UC Berkeley will contribute $1.25 million in matching funds to the project over the next five years. The $1.7 million contributed by the Heising-Simons Foundation will be devoted to supporting research at Berkeley to improve the microwave detectors and to develop fabrication methods that are more efficient and cheaper, with the goal of boosting the number of detectors in CMB experiments by more than a factor of a 10.

    The site in Chile is located in the Parque Astronómico, which is administered by the Comisión Nacional de Investigación Científica y Tecnológica (CONICYT). Since 1998, U.S. investigators and the NSF have worked with Chilean scientists, the University of Chile, and CONICYT to locate multiple projects at this high, dry site to study the CMB.

    See the full article here .

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  • richardmitnick 3:30 pm on December 9, 2016 Permalink | Reply
    Tags: , , , New weapon against Diabetes   

    From ETH Zürich: “New weapon against Diabetes” 

    ETH Zurich bloc

    ETH Zürich

    Peter Rüegg

    Researchers have used the simplest approach yet to produce artificial beta cells from human kidney cells. Like their natural model, the artificial cells act as both sugar sensors and insulin producers.

    Repeated measurement of the blood glucose level and injection of insulin make the everyday life of diabetics complicated. The newly created beta cells of the ETH researchers could make life easier again. (Picture: Dolgachov / iStock)

    Researchers led by ETH Professor Martin Fussenegger at the Department of Biosystems Science and Engineering (D-BSSE) in Basel have produced artificial beta cells using a straightforward engineering approach. These pancreatic cells can do everything that natural ones do: they measure the glucose concentration in the blood and produce enough insulin to effectively lower the blood sugar level. The ETH researchers presented their development in the latest edition of the journal Science.

    Previous approaches were based on stem cells, which the scientists allowed to mature into beta cells either by adding growth factors or by incorporating complex genetic networks.

    For their new approach, the ETH researchers used a cell line based on human kidney cells, HEK cells. The researchers used the natural glucose transport proteins and potassium channels in the membrane of the HEK cells. They enhanced these with a voltage-dependent calcium channel and a gene for the production of insulin and GLP-1, a hormone involved in the regulation of the blood sugar level.

    Voltage switch causes insulin production

    In the artificial beta cells, the HEK cells’ natural glucose transport protein carries glucose from the bloodstream into the cell’s interior. When the blood sugar level exceeds a certain threshold, the potassium channels close. This flips the voltage distribution at the membrane, causing the calcium channels to open. As calcium flows in, it triggers the HEK cells’ built-in signalling cascade, leading to the production and secretion of insulin or GLP-1.

    Diagram of a HEK-beta cell: Extracellular glucose triggers glycolysis-dependent membrane depolarization, which activates the voltage-gated calcium channel, resulting in an influx of Calcium ions, induction of the calmodulincalcineurin signaling cascade, and PNFAT-mediated induction of insulin secretion. (Graphics: ETH Zürich)

    The initial tests of the artificial beta cells in diabetic mice revealed the cells to be extremely effective: “They worked better and for longer than any solution achieved anywhere in the world so far,” says Fussenegger. When implanted into diabetic mice, the modified HEK cells worked reliably for three weeks, producing sufficient quantities of the messengers that regulate blood sugar level.

    Helpful modelling

    In developing the artificial cells, the researchers had the help of a computer model created by researchers working under Jörg Stelling, another professor in ETH Zürich’s Department of Biosystems Science and Engineering (D-BSSE). The model allows predictions to be made of cell behaviour, which can be verified experimentally. “The data from the experiments and the values calculated using the models were almost identical,” says Fussenegger.

    He and his group have been working on biotechnology-based solutions for diabetes therapy for a long time. Several months ago, they unveiled beta cells that had been grown from stem cells from a person’s fatty tissue. This technique is expensive, however, since the beta cells have to be produced individually for each patient. The new solution would be cheaper, as the system is suitable for all diabetics.

    Market-readiness is a long way off

    It remains uncertain, though, when these artificial beta cells will reach the market. They first have to undergo various clinical trials before they can be used in humans. Trials of this kind are expensive and often last several years. “If our cells clear all the hurdles, they could reach the market in 10 years,” the ETH professor estimates.

    Diabetes is becoming the modern-day scourge of humanity. The International Diabetes Federation estimates that more than 640 million people worldwide will suffer from diabetes by 2040. Half a million people are affected in Switzerland today, with 40,000 of them suffering from type 1 diabetes, the form in which the body’s immune system completely destroys the insulin-producing beta cells.


    Xie M et al. Beta-cell-mimetic designer cells provide closed-loop glycemic control. Science, Advanced Online Publication, 8 November 2016, DOI: 10.1126/science.aaf4006

    See the full article here .

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    ETH Zurich campus
    ETH Zurich is one of the leading international universities for technology and the natural sciences. It is well known for its excellent education, ground-breaking fundamental research and for implementing its results directly into practice.

    Founded in 1855, ETH Zurich today has more than 18,500 students from over 110 countries, including 4,000 doctoral students. To researchers, it offers an inspiring working environment, to students, a comprehensive education.

    Twenty-one Nobel Laureates have studied, taught or conducted research at ETH Zurich, underlining the excellent reputation of the university.

  • richardmitnick 3:18 pm on December 9, 2016 Permalink | Reply
    Tags: , Biofilms, , , ,   

    From Caltech: “Protein Disrupts Infectious Biofilms” 

    Caltech Logo



    Lori Dajose
    (626) 395-1217

    Many infectious pathogens are difficult to treat because they develop into biofilms, layers of metabolically active but slowly growing bacteria embedded in a protective layer of slime, which are inherently more resistant to antibiotics. Now, a group of researchers at Caltech and the University of Oxford have made progress in the fight against biofilms. Led by Dianne Newman, the Gordon M. Binder/Amgen Professor of Biology and Geobiology, the group identified a protein that degrades and inhibits biofilms of Pseudomonas aeruginosa, the primary pathogen in cystic fibrosis (CF) infections.

    The work is described in a paper in the journal Science that will appear online December 8.

    Crystal structure of the PodA protein complex with three molecules of 1-hydroxyphenazine, the reaction product, bound in the active sites.
    Credit: Kyle Costa/Caltech

    “Pseudomonas aeruginosa causes chronic infections that are difficult to treat, such as those that inhabit burn wounds, diabetic ulcers, and the lungs of individuals living with cystic fibrosis,” Newman says. “In part, the reason these infections are hard to treat is because P. aeruginosa enters a biofilm mode of growth in these contexts; biofilms tolerate conventional antibiotics much better than other modes of bacterial growth. Our research suggests a new approach to inhibiting P. aeruginosa biofilms.”

    The group targeted pyocyanin, a small molecule produced by P. aeruginosa that produces a blue pigment. Pyocyanin has been used in the clinical identification of this strain for over a century, but several years ago the Newman group demonstrated that the molecule also supports biofilm growth, raising the possibility that its degradation might offer a new route to inhibit biofilm development.

    To identify a factor that would selectively degrade pyocyanin, Kyle Costa, a postdoctoral scholar in biology and biological engineering, turned to a milligram of soil collected in the courtyard of the Beckman Institute on the Caltech campus. From the soil, he isolated another bacterium, Mycobacterium fortuitum, that produces a previously uncharacterized small protein called pyocyanin demethylase (PodA).

    Adding PodA to growing cultures of P. aeruginosa, the team discovered, inhibits biofilm development.

    “While there is precedent for the use of enzymes to treat bacterial infections, the novelty of this study lies in our observation that selectively degrading a small pigment that supports the biofilm lifestyle can inhibit biofilm expansion,” says Costa, the first author on the study. The work, Costa says, is relevant to anyone interested in manipulating microbial biofilms, which are common in natural, clinical, and industrial settings. “There are many more pigment-producing bacteria out there in a wide variety of contexts, and our results pave the way for future studies to explore whether the targeted manipulation of analogous molecules made by different bacteria will have similar effects on other microbial populations.”

    While it will take several years of experimentation to determine whether the laboratory findings can be translated to a clinical context, the work has promise for the utilization of proteins like PodA to treat antibiotic-resistant biofilm infections, the researchers say.

    “What is interesting about this result from an ecological perspective is that a potential new therapeutic approach comes from leveraging reactions catalyzed by soil bacteria,” says Newman. “These organisms likely co-evolved with the pathogen, and we may simply be harnessing strategies other microbes use to keep it in check in nature. The chemical dynamics between microorganisms are fascinating, and we have so much more to learn before we can best exploit them.”

    The paper is titled Pyocyanin degradation by a tautomerizing demethylase inhibits Pseudomonas aeruginosa biofilms. In addition to Costa and Newman, other co-authors include Caltech graduate student Nathaniel Glasser and Professor Stuart Conway of the University of Oxford. The work was funded by the National Institutes of Health’s National Institute of Allergy and Infectious Diseases, the National Science Foundation, the Howard Hughes Medical Institute, the Molecular Observatory at the Beckman Institute at Caltech, the Gordon and Betty Moore Foundation, and the Sanofi-Aventis Bioengineering Research Program at Caltech.

    See the full article here .

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    The California Institute of Technology (commonly referred to as Caltech) is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. “The mission of the California Institute of Technology is to expand human knowledge and benefit society through research integrated with education. We investigate the most challenging, fundamental problems in science and technology in a singularly collegial, interdisciplinary atmosphere, while educating outstanding students to become creative members of society.”
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