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  • richardmitnick 9:25 am on March 23, 2017 Permalink | Reply
    Tags: , , Massive damage throughout Southern California, Newport-Inglewood fault, , UCLA   

    From UCLA via L.A. Times: “Notorious L.A. earthquake fault more dangerous than experts believed, new research shows” 

    UCLA bloc

    UCLA

    1

    L.A. Times

    3.21.17
    Rong-Gong Lin II

    The Newport-Inglewood fault has long been considered one of Southern California’s top seismic danger zones because it runs under some of the region’s most densely populated areas, from the Westside of Los Angeles to the Orange County coast.

    But new research shows that the fault may be even more dangerous than experts had believed, capable of producing more frequent destructive temblors than previously suggested by scientists.

    A new study [Nature] has uncovered evidence that major earthquakes on the fault centuries ago were so violent that they caused a section of Seal Beach near the Orange County coast to fall 1½ to 3 feet in a matter of seconds.

    “It’s not just a gradual sinking. This is boom — it would drop. It’s very rapid sinking,” said the lead author of the report, Robert Leeper, a geology graduate student at UC Riverside who worked on the study as a Cal State Fullerton student and geologist with the U.S. Geological Survey.

    The study of the Newport-Inglewood fault focused on the wetlands of Seal Beach. But the area of sudden dropping could extend to other regions in the same geologic area of the Seal Beach wetlands, which includes the U.S. Naval Weapons Station and the Huntington Harbour neighborhood of Huntington Beach.

    Leeper and a team of scientists at Cal State Fullerton had been searching the Seal Beach wetlands for evidence of ancient tsunami. Instead, they found buried organic deposits that they determined to be the prehistoric remains of marsh surfaces, which they say were abruptly dropped by large earthquakes that occurred on the Newport-Inglewood fault.

    Those earthquakes, roughly dated in 50 BC, AD 200 and the year 1450 — give or take a century or two — were all more powerful than the magnitude 6.4 Long Beach earthquake of 1933, which did not cause a sudden drop in the land, Leeper said.

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    The area shaded in solid white, which spans the Seal Beach National Wildlife Refuge and the Huntington Harbour area of Huntington Beach, highlights the zone along the fault that may experience abrupt sinking during future earthquakes on the Newport-Inglewood fault. (Robert Leeper / Scientific Reports)

    As a result, the observations for the first time suggest that earthquakes as large as magnitudes 6.8 to 7.5 have struck the Newport-Inglewood/Rose Canyon fault system, which stretches from the border of Beverly Hills and Los Angeles through Long Beach and the Orange County coast to downtown San Diego.

    The newly discovered earthquakes suggest that the Newport-Inglewood fault is more active than previously thought. Scientists had believed the Newport-Inglewood fault ruptured in a major earthquake once every 2,300 years on average; the latest results show that a major earthquake could come once every 700 years on average, Leeper said.

    It’s possible the earthquakes can come more frequently than the average, and data suggest they have arrived as little as 300 years apart from one another.

    If a magnitude 7.5 earthquake did rupture on the Newport-Inglewood/Rose Canyon fault system, such a temblor would bring massive damage throughout Southern California, said seismologist Lucy Jones, who was not affiliated with the study. Such an earthquake would produce 45 times more energy than the 1933 earthquake.

    “It’s really clear evidence of three earthquakes on the Newport-Inglewood that are bigger than 1933,” Jones said of the earthquake that killed 120 people. “This is very strong evidence for multiple big earthquakes.”

    The idea that the Newport-Inglewood fault could produce more powerful earthquakes than what happened in 1933 has been growing over the decades. Scientists have come to the consensus that the Newport-Inglewood fault could link up with the San Diego County coast’s Rose Canyon fault, producing a theoretical 7.5 earthquake based on the length of the combined fault system.

    An earthquake of magnitude 7 on the Newport-Inglewood fault would hit areas of Los Angeles west of downtown particularly hard.

    “If you’re on the Westside of L.A., it’s probably the fastest-moving big earthquake that you’re going to have locally,” Jones said. “A 7 on the Newport-Inglewood is going to do a lot more damage than an 8 on the San Andreas, especially for Los Angeles.”

    The study focused on taking samples of sediment underneath the Seal Beach National Wildlife Refuge in 55 locations across a broad zone, mapping buried layers for signs of past seismic activity.

    To do this, scientists used a vibrating machine to push down a 20-foot-long, sharp-tipped pipe into the sediment and extract sediment samples that gave them a look at what has happened geologically underneath the site.

    They found a repeating pattern where living vegetation on the marsh suddenly dropped by up to 3 feet, submerging it underwater, eventually killing everything on the surface and later buried.

    “We identified three of these buried layers [composed of] vegetation or sediment that used to be at the surface,” Leeper said. “These buried, organic-rich layers are evidence of three earthquakes on the Newport-Inglewood in the past 2,000 years.”

    Earthquakes elsewhere have also caused sudden drops in land, such as off the Cascadia subduction zone along the coast of Oregon and Washington. There, pine trees that once grew above the beach suddenly dropped below sea level, killing the trees as salt water washed over their roots, said study coauthor Kate Scharer, a USGS research geologist.

    Another reason pointing to major earthquakes as a cause is the existence of a gap — known as the Sunset Gap — in the Newport-Inglewood fault that roughly covers the Seal Beach National Wildlife Refuge and Huntington Harbour.

    The gap is oriented in a way that, if a major earthquake strikes, land could suddenly drop. Such depressions have formed in other Southern California faults, which have created Lake Elsinore from the Elsinore fault, and created Quail Lake, Elizabeth Lake and Hughes Lake from the San Andreas fault, Jones said.

    While the scientists focused their study on the Seal Beach wetlands, because Huntington Harbour and the Naval Weapons Station area also lie in the same gap of the Newport-Inglewood fault, it could be possible that the sinking would extend to those areas as well, Leeper said.

    But further study would be a good idea for those areas. It’s possible that an investigation of Huntington Harbour, for instance, would show that land underneath it did not drop during earthquakes but moved horizontally, like much of the rest of the Newport-Inglewood fault, Scharer said.

    Sudden dropping of land could cause damage to infrastructure, Scharer said, such as roads or pipes not designed to handle such a rapid fall.

    Nothing in the new study offers guidance for when the next major earthquake on the Newport-Inglewood fault will strike next. “Earthquakes can happen at any time. We can’t predict them. All we can do is try to understand how often they occur in the past, and be prepared for when the next one does occur,” Leeper said.

    Scientists generally say that the chances of a major quake on the San Andreas fault are higher in our lifetime because that fault is moving so much faster than the Newport-Inglewood, at a rate of more than 1 inch a year compared with a rate of one-twenty-fifth of an inch a year.

    But it’s possible a big earthquake on the Newport-Inglewood fault could happen in our lifetime.

    The study was published online Monday in Scientific Reports, a research publication run by the journal Nature [link is above].

    Besides Leeper and Scharer, the other coauthors of the study are Brady Rhodes, Matthew Kirby, Joseph Carlin and Angela Aranda of Cal State Fullerton; Scott Starratt of the USGS; Simona Avnaim-Katav and Glen MacDonald of UCLA; and Eileen Hemphill-Haley.

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    Researchers studied prehistoric layers of sediment in a gap of the Newport-Inglewood fault known as the Sunset Gap. They took sediment samples from 55 locations that suggest the land in this region suddenly dropped by as much as 3 feet during major earthquakes. (Robert Leeper / Scientific Reports)

    See the full article here .

    You can help many citizen scientists in detecting earthquakes and getting the data to emergency services people in affected area.

    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).

    BOINCLarge

    BOINC WallPaper

    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

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    UC LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
  • richardmitnick 10:18 am on March 21, 2017 Permalink | Reply
    Tags: , Cell phone technology, DNA biomarkers, Intercalator dyes, , UCLA, UCLA researchers make DNA detection portable affordable using cellphones   

    From UCLA: “UCLA researchers make DNA detection portable, affordable using cellphones” 

    UCLA bloc

    UCLA

    March 20, 2017
    Matthew Chin

    System achieved comparable results to equipment costing tens of thousands of dollars more.

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    The combined dye/cellphone reader system achieved comparable results to equipment costing tens of thousands of dollars more. Dino Di Carlo/UCLA

    Researchers at UCLA have developed an improved method to detect the presence of DNA biomarkers of disease that is compatible with use outside of a hospital or lab setting. The new technique leverages the sensors and optics of cellphones to read light produced by a new detector dye mixture that reports the presence of DNA molecules with a signal that is more than 10-times brighter.

    Nucleic acids, such as DNA or RNA, are used in tests for infectious diseases, genetic disorders, cancer mutations that can be targeted by specific drugs, and fetal abnormality tests. The samples used in standard diagnostic tests typically contain only tiny amounts of a disease’s related nucleic acids. To assist optical detection, clinicians amplify the number of nucleic acids making them easier to find with the fluorescent dyes.

    Both the amplification and the optical detection steps have in the past required costly and bulky equipment, largely limiting their use to laboratories.

    In a study published online in the journal ACS Nano, researchers from three UCLA entities — the Henry Samueli School of Engineering and Applied Science, the California NanoSystems Institute, and the David Geffen School of Medicine — showed how to take detection out of the lab and for a fraction of the cost.

    The collaborative team of researchers included lead author Janay Kong, a UCLA Ph.D. student in bioengineering; Qingshan Wei, a post-doctoral researcher in electrical engineering; Aydogan Ozcan, Chancellor’s Professor of Electrical Engineering and Bioengineering; Dino Di Carlo, professor of bioengineering and mechanical and aerospace engineering; and Omai Garner, assistant professor of pathology and medicine at the David Geffen School of Medicine at UCLA.

    The UCLA researchers focused on the challenges with low-cost optical detection. Small changes in light emitted from molecules that associate with DNA, called intercalator dyes, are used to identify DNA amplification, but these dyes are unstable and their changes are too dim for standard cellphone camera sensors.

    But the team discovered an additive that stabilized the intercalator dyes and generated a large increase in fluorescent signal above the background light level, enabling the test to be integrated with inexpensive cellphone based detection methods. The combined novel dye/cellphone reader system achieved comparable results to equipment costing tens of thousands of dollars more.

    To adapt a cellphone to detect the light produced from dyes associated with amplified DNA while those samples are in standard laboratory containers, such as well plates, the team developed a cost-effective, field-portable fiber optic bundle. The fibers in the bundle routed the signal from each well in the plate to a unique location of the camera sensor area. This handheld reader is able to provide comparable results to standard benchtop readers, but at a fraction of the cost, which the authors suggest is a promising sign that the reader could be applied to other fluorescence-based diagnostic tests.

    “Currently nucleic acid amplification tests have issues generating a stable and high signal, which often necessitates the use of calibration dyes and samples which can be limiting for point-of-care use,” Di Carlo said. “The unique dye combination overcomes these issues and is able to generate a thermally stable signal, with a much higher signal to noise ratio. The DNA amplification curves we see look beautiful — without any of the normalization and calibration, which is usually performed, to get to the point that we start at.”

    Additionally, the authors emphasized that the dye combinations discovered should be able to be used universally to detect any nucleic acid amplification, allowing for their use in a multitude of other amplification approaches and tests.

    The team demonstrated the approach using a process called loop-mediated isothermal amplification, or LAMP, with DNA from lambda phage as the target molecule, as a proof of concept, and now plan to adapt the assay to complex clinical samples and nucleic acids associated with pathogens such as influenza.

    The newest demonstration is part of a suite of technologies aimed at democratizing disease diagnosis developed by the UCLA team. Including low-cost optical readout and diagnostics based on consumer-electronic devices, microfluidic-based automation and molecular assays leveraging DNA nanotechnology.

    This interdisciplinary work was supported through a team science grant from the National Science Foundation Emerging Frontiers in Research and Innovation program.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    UC LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
  • richardmitnick 12:10 pm on March 16, 2017 Permalink | Reply
    Tags: , , , HD 106906b, Planetary evolution, UCLA   

    From UCLA: “Gigantic Jupiter-type planet reveals insights into how planets evolve” 

    UCLA bloc

    UCLA

    March 15, 2017
    Stuart Wolpert

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    HD 106906. No image credit

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    Simulated image of the HD 106906 stellar debris disk, showing a ring of rocky planet-forming material. Erika Nesvold/Carnegie Institution for Science

    An enormous young planet approximately 300 light-years from Earth has given astrophysicists a rare glimpse into planetary evolution.

    The planet, known as HD 106906b, was discovered in 2014 by a team of scientists from the U.S., the Netherlands and Italy. It is 11 times the mass of Jupiter and is extremely young by celestial standards — not more than 13 million years old, compared with our solar system’s 4.6 billion years.

    “This is such a young star; we have a snapshot of a baby star that just formed its planetary system — a rare peek at the final stage of planet formation,” said Smadar Naoz, a UCLA assistant professor of physics and astronomy, and a co-author of the study.

    Another of the planet’s unusual characteristics is its distance from its star. Astronomers believe that the vast majority of planets outside of our solar system exist inside a vast dusty disk of debris relatively close to the center of the solar system. But HD 106906b is far beyond its solar system’s disk — so far away that it takes 1,500 years for the planet to orbit its star. HD 106906b is currently at least 650 times as far from its star as the Earth is from our sun.

    “Our current planet formation theories do not account for a planet beyond its debris disk,” Naoz said.

    The study’s lead author is Erika Nesvold, a postdoctoral fellow at the Carnegie Institution for Science whom Naoz mentors. She wrote software called Superparticle-Method Algorithm for Collisions in Kuiper belts and debris disks, or SMACK, that allowed the researchers to create a model of the planet’s orbital path — a critical step because HD 106906b orbits so slowly that the researchers can barely see it move.

    The research, published online in the Astrophysical Journal Letters, suggests that the planet formed outside the disk, where it’s visible it today, as opposed to having been formed inside the debris disk and then having been thrust far beyond it.

    Naoz said that conclusion helps explain the shape of the debris disk. “It works perfectly,” she said.

    The planet’s orbit is elliptical; it gets much closer to the star on one side of its orbit than on the other side. And its gravity produces an elliptical shape in the disk as well. One side of the disk is closer to the star than the other side, and the dust on that side is warmer and glows brighter as a result.

    The debris disk was photographed in 2016 by American and European astronomers. According to Naoz, the disk is an analog to our solar system’s Kuiper belt — an enormous cluster of small bodies like comets and minor planets located beyond Neptune.

    The researchers don’t know if there are additional planets inside the disk, but using Nesvold’s software — which also been used to study other debris disks in the universe — they were able to re-create the shape of the disk without adding another planet into the model, as some astronomers had thought would be required.

    Debris disks are composed of gas, dust and ice, and they play a key role in the formation of planets. Typically, Naoz said, planets form after a gas cloud collapses due to its own gravity, forming a disk — where planets are created — and a star. As the gas slowly evaporates, the dust and debris rotate and collide around the young star until gravity pushes them away, forming a structure like our solar system’s Kuiper belt.

    “In our solar system, we’ve had billions of years of evolution,” said Michael Fitzgerald, UCLA associate professor of physics and astronomy, and the study’s other co-author. “We’re seeing this young system revealed to us before it has had a chance to dynamically mature.”

    Naoz said the researchers’ conclusions do not require any exotic physics or hidden planets to explain them, which is not always the case in studying other solar systems.

    “There are no assumptions; this is just physics,” she said.

    Naoz’s research was funded by a research fellowship from the Alfred P. Sloan Foundation. Nesvold’s was supported by a Carnegie Department of Terrestrial Magnetism postdoctoral fellowship.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    UC LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
  • richardmitnick 9:22 am on March 2, 2017 Permalink | Reply
    Tags: AAU, , UCLA,   

    From UCLA: Women in STEM -“UCLA to Enhance Undergraduate STEM Education” 

    UCLA bloc

    UCLA

    March 01, 2017

    1
    From the left, Erin Sanders, Gina Poe and Megan McEvoy.UCLA

    UCLA is among 12 universities nationally to be awarded a grant from the Association of American Universities to fund workshops on campus over the next year to assess all programs that support and retain undergraduate students in science, technology, engineering and mathematics (STEM).

    The first workshop, to be held in late spring on campus, will focus on advising, tutoring, career contacts with alumni, research activities and other-curricular student support programs and activities. A second workshop in the fall will examine changes in how courses are taught, how grades are assessed and ways to change the culture in and outside the classroom to better support students in their educational goals. A third workshop,to be held next year, will bring all relevant stakeholders together to discuss a variety of issues on which they can work together and to identify gaps that can be filled.

    These workshops will be organized by life sciences professors Gina Poe and Megan McEvoy, co-directors of UCLA’s new Center for Opportunities to Maximize Participation, Access, and Student Success (COMPASS) and by Erin Sanders of the Center for Education Innovation and Learning in the Sciences. Nearly 200 STEM stakeholders across campus will be invited to attend the workshops.

    Each meeting will be attended by the deans of engineering, life sciences, physical sciences, public health, and the dean and vice provost for undergraduate education,. They will use the findings to plan funding priorities and to create lasting change, Poe said.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    UC LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
  • richardmitnick 7:51 am on February 22, 2017 Permalink | Reply
    Tags: , , New nanoscale antenna array, Terahertz detectors, UCLA, Useful for biological sensing and medical imaging chemical identification and material characterization   

    From UCLA: “UCLA engineers develop high-performance terahertz detectors” 

    UCLA bloc

    UCLA

    February 21, 2017
    Matthew Chin

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    UCLA electrical engineering graduate student Nezih Tolga Yardimci. Art Montes De Oca/UCLA Engineering

    Researchers from the UCLA Henry Samueli School of Engineering and Applied Science have developed a new antenna array that greatly expands the operation bandwidth and level of sensitivity for imaging and sensing systems that use terahertz frequencies.

    Terahertz frequencies are an underused part of the electromagnetic spectrum that lies between the infrared and microwave bands. The unique features of this part of the spectrum could be useful for biological sensing and medical imaging, chemical identification and material characterization.

    “For example, a terahertz-based imaging system could allow doctors to see how wounds are healing underneath bandages,” said Mona Jarrahi, associate professor of electrical engineering in the UCLA Henry Samueli School of Engineering and Applied Science and the principal investigator of the research. The study was published in Scientific Reports, an open-access journal from Nature.

    However terahertz technology is not yet mature. One component researchers are aiming to make more efficient is a terahertz detector, which receives the terahertz signals, much like photodetectors in a camera that sense light to produce an image.

    By operating across a broader bandwidth, the new nanoscale antenna array developed by Jarrahi and Nezih Tolga Yardimci, a UCLA graduate student in electrical engineering, can extract more information about material characteristics. The device’s higher signal-to-noise ratios mean it can find faint target signals. For example, the new terahertz detector can be tuned to detect certain chemicals even when target molecules are present in miniscule amounts. It can also be used to image both the surface of the skin, and deeper tissue layers.

    The unique nanoscale geometry of the antenna array addresses the bandwidth and sensitivity problems of previously used terahertz detectors, the researchers said.

    “Up close, it looks like a row of small grates,” Yardimci said. “We specifically designed the dimensions of the nanoantenna elements and their spacing such that an incoming terahertz beam is focused into nanoscale dimensions, where it efficiently interacts with a stream of optical pump photons to produce an electrical signal proportional to the terahertz beam intensity.”

    Jarrahi said: “The broad operation bandwidth and high sensitivity of this new type of terahertz detector extends the scope and potential uses of terahertz waves for many imaging and sensing applications.”

    The research was supported by financial support from Moore Inventor Fellowship and the Presidential Early Career Award for Scientists and Engineers.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    UC LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
  • richardmitnick 9:00 pm on February 15, 2017 Permalink | Reply
    Tags: Aromawa Shields, , UCLA,   

    From UCLA: Women in STEM – “Astrobiology’s rising star” Aromawa Shields 

    UCLA bloc

    UCLA

    February 14, 2017
    Nicole Freeling

    1
    Aromawa Shields has used her acting ability to communicate complex science to audiences. Coutesy of TED Talks

    Aomawa Shields studies the climate on distant planets. Her aim: to find those most likely to host alien life. The astrobiologist is a National Science Foundation astronomy and astrophysics postdoctoral fellow working in UCLA’s department of physics and astronomy.

    But she was also an actress with an M.F.A. from UCLA’s School of Theater, Film and Television That’s given her a secret “superpower” that’s helped her make science accessible, a talent that’s attracted nearly 1.5 million views of her engaging TED talk on her search for other life forms in the universe.

    “I’m an African-American female astronomer and a classically trained actress who loves to wear makeup and read fashion magazines. So I am uniquely positioned to appreciate contradictions in nature,” she said in her TED talk, laughing, “and how they can inform our search for the next planet where life exists.”

    In July, Shields starts a new job, as the Clare Boothe Luce Assistant Professor at UC Irvine. A participant in the University of California President’s Postdoctoral Fellowship Program, she is among 24 fellows newly hired by UC campuses this year. The program, which prepares outstanding Ph.D.s for faculty careers, has been lauded as a national model for expanding faculty diversity.

    She talked to Nicole Freeling of the UC Office of the President about her unusual career path, the search for E.T. and her efforts to groom a new generation of star scientists by mentoring middle school girls in an organization she founded, Rising Stargirls.

    What is astrobiology, and how does your work fit in?

    Astrobiology is the study of life in the universe: how it got started on this planet, how it has evolved over time and how widely distributed it might be elsewhere.
    The way I come to the question of “Are we alone?” is to find planets that might have environments suitable for life to develop and sustain itself.

    I use climate models of all different types — most recently, ones that are three-dimensional — to look at the collaboration between surface, atmosphere and incoming starlight and how those interactions affect the climate of a planet.

    Say, there was a habitability pageant for planets. You wouldn’t want to select those that would only be warm enough for surface water under very specific conditions. You’d want planets that could be warm enough for liquid water over a wide range of atmospheres, orbits and surfaces.

    Our goal is to generate a list of planets that are most likely to succeed in the habitability category. That can tell us where to point our telescopes.

    What planets are at the top of your list now?

    A planet was discovered just a few months ago called Proxima Centauri b. That one is particularly exciting because it is orbiting the closest star system to us — just 4.2 light years away.

    It’s in the habitable zone — the region around the star where you might expect the planet to be warm enough to have water on its surface. But as my work has highlighted, just because a planet is in a star’s habitable zone, that doesn’t make it habitable — and just because it’s habitable doesn’t mean it’s inhabited.

    How did you first get interested in this question of “Are we alone?”

    I started looking up at the stars when I was 12, when my seventh grade class watched the movie “Space Camp” about this group of kids who were launched into space.

    Up until that point, I wanted to be a ton of things — a Dallas Cowboys cheerleader, a secretary, an orthopedist. But it wasn’t until seeing this movie that I was, like, that’s it. And, unlike the other aspirations, this one never really went away.

    Your career wasn’t exactly linear, though. You took a decade off from astronomy to earn an M.F.A. from UCLA and work as a professional actress. What led you down that path, and how has it influenced your career as a scientist?

    At first, when I was in college, it seemed that science wasn’t all I thought it was cracked up to be. I was very focused on problem sets and exams, and I forgot the bigger picture: that those are the things you have to get through before you can get to the exciting stuff, which is research.

    Science, as I came to find out, is a very creative endeavor. But at the time I felt like science was over here, and my creative life was over there — and that creative life was just so much more fun.

    It took me a long time to feel connected to what I created as a scientist, rather than detached from it. [But] eventually, I came back to the field. I realized that this was what I was supposed to be doing.

    And it finally occurred to me in grad school that this non-traditional background, which I thought had been an Achilles’ heel, was actually a superpower. It allowed me to communicate the impact of my science the way some other classmates and scientists had trouble doing.

    When you’re not looking for life on other planets, you run Rising Stargirls, a program that uses creative arts to inspire middle school girls to explore the stars. What interested you in mentoring young girls, and why use art as a path to science?

    There was always this feeling that I had to be a certain type of scientist. There were parts of myself that I felt I had to downplay — whether it was by wearing subdued clothes, not wearing makeup, looking very stereotypically masculine, not displaying emotion.

    I don’t believe that anymore.

    I want young girls, especially girls of color and especially middle school-age girls — to understand they can bring all of themselves into their interest in science.

    Art, writing and theater, which are more readily accepted as being personal, can be a gateway to help girls be personally invested in what they’re learning.

    As a woman of color, as well as a returning graduate student, what helped you succeed in a field where you were often something of the odd one out?

    In one word: mentors. The people who answered my questions by sitting down with me for 15 minutes or an hour; who gave me tips, feedback, lessons learned, things they wish they’d known; who helped me negotiate for things I needed to bring my vision to my institution.

    I adopted this attitude of: Whoever has done what I want to do, I’m going to go ask them how they did it. And if they don’t want to share that with me, that’s fine. I’ll go and ask someone else.

    In my experience, pretty much everyone I’ve asked for help has provided it, in whatever way they could spare. And it’s led to a series of successes that have put me in the position I am today.

    The President’s Postdoctoral Fellowship Program is part of that. If I trace back what I know now about how to be a successful researcher, PPFP played a crucial role in my development.

    You write in your blog, Variable Stargirl, about your struggles with imposter syndrome and the feeling of “Is this me, can I do this?” Talk about what imposter syndrome is and how you dealt with it?

    I used to think that I was the only person who suffered from it. I remember a lecturer at a workshop asking if anyone had experienced imposter syndrome, and everyone raised a hand — including professors who were white males. It’s more of a wide-ranging phenomenon in academia than I would have ever anticipated.

    But at least for me, as someone who comes from a community that has historically been marginalized — both as a woman and as an African-American — the propensity to be susceptible to imposter syndrome is especially acute. And, as an older, returning student, I had this feeling that, “Oh my gosh. Everyone who is 20-something has the jump on me. They remember more. They were just in physics courses two months ago, and for me it’s been 11 years.”

    As scientists, evidence is what we value most highly. It’s about following what the data say, not letting preconceived notions dictate your conclusion.

    I’ve had to take an active role in looking at the evidence. I’m a visual person, so actually being able to read the email that said, “You passed your qualifying exam” or looking at the 4.0 that I got in extragalactic astronomy — those things helped me to retrain my mind.

    What that’s done for me is to take those old voices saying, “Everyone else but you is a part of this field,” or “You can’t do it,” and dial the volume way down — so that it’s chatter in the background as opposed to it becoming an obstacle to proceeding with one’s day or one’s academic career.

    Any parting words of advice for aspiring scientists?

    My personal mantra is it’s never too late. The “shoulds” can be debilitating. If possible, I’d say eliminate that word from your vocabulary. It’s about: What do you want now, and who has it? And what can you do to get it too?

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    UC LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
  • richardmitnick 3:28 pm on February 10, 2017 Permalink | Reply
    Tags: , , , Dwarf star 200 light-years away contains life’s building blocks, The constellation Boötes, UCLA, WD 1425+540,   

    From UCLA: “Dwarf star 200 light-years away contains life’s building blocks” 

    UCLA bloc

    UCLA

    February 09, 2017
    Stuart Wolpert

    UCLA-led team discovers object in the constellation Boötes with carbon, nitrogen, oxygen and hydrogen.

    rendering
    Rendering of a white dwarf star (bright white spot), with rocky debris from former asteroids or a minor planet that has been broken apart by gravity (red rings). University of Warwick

    Many scientists believe the Earth was dry when it first formed, and that the building blocks for life on our planet — carbon, nitrogen and water — appeared only later as a result of collisions with other objects in our solar system that had those elements.

    Today, a UCLA-led team of scientists reports that it has discovered the existence of a white dwarf star whose atmosphere is rich in carbon and nitrogen, as well as in oxygen and hydrogen, the components of water. The white dwarf is approximately 200 light-years from Earth and is located in the constellation Boötes.

    Benjamin Zuckerman, a co-author of the research and a UCLA professor of astronomy, said the study presents evidence that the planetary system associated with the white dwarf contains materials that are the basic building blocks for life. And although the study focused on this particular star — known as WD 1425+540 — the fact that its planetary system shares characteristics with our solar system strongly suggests that other planetary systems would also.

    “The findings indicate that some of life’s important preconditions are common in the universe,” Zuckerman said.

    The scientists report that a minor planet in the planetary system was orbiting around the white dwarf, and its trajectory was somehow altered, perhaps by the gravitational pull of a planet in the same system. That change caused the minor planet to travel very close to the white dwarf, where the star’s strong gravitational field ripped the minor planet apart into gas and dust. Those remnants went into orbit around the white dwarf — much like the rings around Saturn, Zuckerman said — before eventually spiraling onto the star itself, bringing with them the building blocks for life.

    The researchers think these events occurred relatively recently, perhaps in the past 100,000 years or so, said Edward Young, another co-author of the study and a UCLA professor of geochemistry and cosmochemistry. They estimate that approximately 30 percent of the minor planet’s mass was water and other ices, and approximately 70 percent was rocky material.

    The research suggests that the minor planet is the first of what are likely many such analogs to objects in our solar system’s Kuiper belt. The Kuiper belt is an enormous cluster of small bodies like comets and minor planets located in the outer reaches of our solar system, beyond Neptune.

    Kuiper Belt. Minor Planet Center
    Kuiper Belt. Minor Planet Center

    Astronomers have long wondered whether other planetary systems have bodies with properties similar to those in the Kuiper belt, and the new study appears to confirm for the first time that one such body exists.

    White dwarf stars are dense, burned-out remnants of normal stars. Their strong gravitational pull causes elements like carbon, oxygen and nitrogen to sink out of their atmospheres and into their interiors, where they cannot be detected by telescopes.

    The research, published in the Astrophysical Journal Letters, describes how WD 1425+540 came to obtain carbon, nitrogen, oxygen and hydrogen. This is the first time a white dwarf with nitrogen has been discovered, and one of only a few known examples of white dwarfs that have been impacted by a rocky body that was rich in water ice.

    “If there is water in Kuiper belt-like objects around other stars, as there now appears to be, then when rocky planets form they need not contain life’s ingredients,” said Siyi Xu, the study’s lead author, a postdoctoral scholar at the European Southern Observatory in Germany who earned her doctorate at UCLA.

    “Now we’re seeing in a planetary system outside our solar system that there are minor planets where water, nitrogen and carbon are present in abundance, as in our solar system’s Kuiper belt,” Xu said. “If Earth obtained its water, nitrogen and carbon from the impact of such objects, then rocky planets in other planetary systems could also obtain their water, nitrogen and carbon this way.”

    A rocky planet that forms relatively close to its star would likely be dry, Young said.

    “We would like to know whether in other planetary systems Kuiper belts exist with large quantities of water that could be added to otherwise dry planets,” he said. “Our research suggests this is likely.”

    According to Zuckerman, the study doesn’t settle the question of whether life in the universe is common.

    “First you need an Earth-like world in its size, mass and at the proper distance from a star like our sun,” he said, adding that astronomers still haven’t found a planet that matches those criteria.

    The researchers observed WD 1425+540 with the Keck Telescope in 2008 and 2014, and with the Hubble Space Telescope in 2014.

    Keck Observatory, Mauna Kea, Hawaii, USA
    Keck Observatory, Mauna Kea, Hawaii, USA

    NASA/ESA Hubble Telescope
    NASA/ESA Hubble Telescope

    They analyzed the chemical composition of its atmosphere using an instrument called a spectrometer, which breaks light into wavelengths. Spectrometers can be tuned to the wavelengths at which scientists know a given element emits and absorbs light; scientists can then determine the element’s presence by whether it emits or absorbs light of certain characteristic wavelengths. In the new study, the researchers saw the elements in the white dwarf’s atmosphere because they absorbed some of the background light from the white dwarf.

    In addition to Xu, Young and Zuckerman, co-authors of the research are Michael Jura, a UCLA professor of astronomy who died in 2016; Beth Klein, a former graduate student of Jura’s; and Patrick Dufour, an assistant professor of physics at the University of Montreal.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    UC LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
  • richardmitnick 1:25 pm on February 8, 2017 Permalink | Reply
    Tags: Pluripotent stem cells, , UCLA, UCLA researchers turn stem cells into somites the precursors to skeletal muscle cartilage and bone   

    From UCLA: “UCLA researchers turn stem cells into somites, precursors to skeletal muscle, cartilage and bone” 

    UCLA bloc

    UCLA

    February 07, 2017
    Sarah C.P. Williams

    1
    The new protocol turned 90 percent of human pluripotent stem cells into somite cells in just four days; those somite cells then generated (left to right) cartilage, bone and muscle cells. UCLA Broad Stem Cell Research Center/Cell Reports

    FINDINGS

    Adding just the right mixture of signaling molecules — proteins involved in development — to human stem cells can coax them to resemble somites, which are groups of cells that give rise to skeletal muscles, bones, and cartilage in developing embryos. The somites-in-a-dish then have the potential to generate these cell types in the lab, according to new research led by senior author April Pyle at the Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research at UCLA.

    BACKGROUND

    Pluripotent stem cells, by definition, can become any type of cell in the body, but researchers have struggled to guide them to produce certain tissues, including muscle. In developing human embryos, muscle cells — as well as the bone and cartilage of vertebrae and ribs, among other cell types — arise from small clusters of cells called somites.

    Researchers have studied how somites develop in animals and identified the molecules that seem to be an important part of that process in animals. But when scientists have tried to use those molecules to coax human stem cells to generate somites, the protocols have been inefficient.

    METHOD

    The scientists isolated the minuscule developing human somites and measured expression levels of different genes both before and after the somites were fully formed. For each gene that changed levels during the process, the researchers tested whether adding molecules to boost or suppress the function of that gene in human pluripotent stem cells helped push the cells to become somite-like. They found that the optimal mixture of molecules in humans was different than what had been tried in animals. Using the new combination, they could turn 90 percent of human stem cells into somite cells in just four days.

    The scientists followed the cells over the next four weeks and determined that they were indeed able to generate cells including skeletal muscle, bone and cartilage that normally develop from somites.

    IMPACT

    The new protocol to create somite-like cells from human pluripotent stem cells opens the door to researchers who want to make muscle, bone and cartilage cells in the lab. Pyle’s group plans to study how to use muscle cells generated from the new somites to treat Duchenne muscular dystrophy, a severe form of muscle degeneration that currently does not have a cure.

    AUTHORS

    Pyle is a UCLA associate professor of microbiology, immunology and molecular genetics. The first author of the study is Haibin Xi; co-authors are Wakana Fujiwara, Karen Gonzalez and Majib Jan of UCLA; Katja Schenke-Layland and Simone Liebscher of Germany’s Eberhard Karls University Tübingen; and Ben Van Handel of CarthroniX Inc., a California-based biopharmaceutical company.

    JOURNAL

    The study was published in the journal Cell Reports.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    UC LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
  • richardmitnick 1:34 pm on February 7, 2017 Permalink | Reply
    Tags: , Biomathematics, , , New study is an advance toward preventing a ‘post-antibiotic era’, UCLA   

    From UCLA: “New study is an advance toward preventing a ‘post-antibiotic era’ “ 

    UCLA bloc

    UCLA

    February 07, 2017
    Stuart Wolpert

    UCLA biologists identify drug combinations that may be highly effective at reducing growth of deadly bacteria

    1
    UCLA’s Elif Tekin, Casey Beppler, Pamela Yeh and Van Savage are gaining insights into why certain groups of three antibiotics interact well together and others don’t.

    A landmark report by the World Health Organization in 2014 observed that antibiotic resistance — long thought to be a health threat of the future — had finally become a serious threat to public health around the world. A top WHO official called for an immediate and aggressive response to prevent what he called a “post-antibiotic era, in which common infections and minor injuries which have been treatable for decades can once again kill.”

    A team of UCLA biologists has been responding to the challenge, exploring possible ways to defeat life-threatening antibiotic-resistant bacteria. In 2016, they reported that combinations of three different antibiotics can often overcome bacteria’s resistance to antibiotics, even when none of the three antibiotics on its own — or even two of the three together — is effective.

    Their latest work, which is published online and appears in the current print edition of the Journal of the Royal Society Interface, extends their understanding of that phenomenon and identifies two combinations of drugs that are unexpectedly successful in reducing the growth of E. coli bacteria.

    A key to the study is an understanding that using two, three or more antibiotics in combination does not necessarily make the drugs more effective in combating bacteria — in fact, in many cases, their effectiveness is actually reduced when drugs are used together — so the combinations must be chosen carefully and systematically. The new paper also provides the first detailed explanation of how the scientists created a mathematical formula that can help predict which combinations of drugs will be most effective.

    The scientists tested every possible combination of a group of six antibiotics, including 20 different combinations of three antibiotics at a time.

    Among the three-drug combinations, the researchers found two that were noticeably more effective than they had expected. Those groupings used treatments from three different classes of antibiotics, so the combinations used a wide range of mechanisms to fight the bacteria. (Five of the three-drug combinations were less effective than they expected, and the other 13 groupings performed as they predicted.)

    2
    Pamela Yeh. Reed Hutchinson/UCLA

    “So many bacteria are now so resistant to antibiotics,” said Pamela Yeh, the study’s senior author and a UCLA assistant professor of ecology and evolutionary biology. “We have a logical, methodical way to identify three-drug combinations to pursue. We think it’s vital to have this framework for identifying the best possible combinations of antibiotics.”

    The researchers have identified cases where the effects of the interactions are larger than the sum of the parts.

    “Doctors may want to super-efficiently kill the bacteria, and that is what these enhanced interactions make possible,” said lead author Casey Beppler, who was an undergraduate in Yeh’s laboratory and is now a graduate student at UC San Francisco.

    For the current study, the scientists evaluated the drug combinations on plates in a lab. Beppler said a next step will be to test the most effective combinations in mice.

    In addition to reporting on how well various combinations of antibiotics worked, the paper also presents a mathematical formula the biologists developed for analyzing how three or more factors interact and of explaining complex, unexpected interactions. The framework would be useful for solving other questions in the sciences and social sciences in which researchers analyze how three or more components might interact — for example, how climate is affected by the interplay among temperature, rainfall, humidity and ocean acidity.

    The biologists are gaining a deep understanding of why certain groups of three antibiotics interact well together, and others don’t, said Van Savage, a co-author of the paper and a UCLA professor of ecology and evolutionary biology and of biomathematics.

    Beppler said more research is needed to determine which combinations are optimal for specific diseases and for specific parts of the body. And the researchers now are using the mathematical formula to test combinations of four antibiotics.

    Co-authors of the new research are Elif Tekin, a UCLA graduate student in Savage’s laboratory; Zhiyuan Mao, Cynthia White, Cassandra McDiarmid and Emily Vargas, who were undergraduates in Yeh’s laboratory; and Jeffrey H. Miller, a UCLA distinguished professor of microbiology, immunology and molecular genetics.

    Yeh’s research was funded by the Hellman Foundation. Savage’s research was funded by a James S. McDonnell Foundation Complex Systems Scholar Award and from the National Science Foundation. Beppler received funding from the National Institutes of Health Initiative to Maximize Student Development.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    UC LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
  • richardmitnick 9:24 am on February 2, 2017 Permalink | Reply
    Tags: Advanced electron microscopy, , , GENFIRE (GENeralized Fourier Iterative Reconstruction), , Mapping out the three-dimensional atomic positions at the grain boundaries for the first time, , , UCLA   

    From UCLA: “UCLA physicists map the atomic structure of an alloy” 

    UCLA bloc

    UCLA

    February 01, 2017
    Katherine Kornei

    1
    Identification of the precise 3-D coordinates of iron, shown in red, and platinum atoms in an iron-platinum nanoparticle. Courtesy of Colin Ophus and Florian Nickel

    In the world of the very tiny, perfection is rare: virtually all materials have defects on the atomic level. These imperfections — missing atoms, atoms of one type swapped for another, and misaligned atoms — can uniquely determine a material’s properties and function. Now, UCLA physicists and collaborators have mapped the coordinates of more than 23,000 individual atoms in a tiny iron-platinum nanoparticle to reveal the material’s defects.

    The results demonstrate that the positions of tens of thousands of atoms can be precisely identified and then fed into quantum mechanics calculations to correlate imperfections and defects with material properties at the single-atom level. This research will be published Feb. 2 in the journal Nature.

    Jianwei “John” Miao, a UCLA professor of physics and astronomy and a member of UCLA’s California NanoSystems Institute, led the international team in mapping the atomic-level details of the bimetallic nanoparticle, more than a trillion of which could fit within a grain of sand.

    “No one has seen this kind of three-dimensional structural complexity with such detail before,” said Miao, who is also a deputy director of the Science and Technology Center on Real-Time Functional Imaging. This new National Science Foundation-funded consortium consists of scientists at UCLA and five other colleges and universities who are using high-resolution imaging to address questions in the physical sciences, life sciences and engineering.

    Miao and his team focused on an iron-platinum alloy, a very promising material for next-generation magnetic storage media and permanent magnet applications.

    By taking multiple images of the iron-platinum nanoparticle with an advanced electron microscope at Lawrence Berkeley National Laboratory and using powerful reconstruction algorithms developed at UCLA, the researchers determined the precise three-dimensional arrangement of atoms in the nanoparticle.

    “For the first time, we can see individual atoms and chemical composition in three dimensions. Everything we look at, it’s new,” Miao said.

    The team identified and located more than 6,500 iron and 16,600 platinum atoms and showed how the atoms are arranged in nine grains, each of which contains different ratios of iron and platinum atoms. Miao and his colleagues showed that atoms closer to the interior of the grains are more regularly arranged than those near the surfaces. They also observed that the interfaces between grains, called grain boundaries, are more disordered.

    “Understanding the three-dimensional structures of grain boundaries is a major challenge in materials science because they strongly influence the properties of materials,” Miao said. “Now we are able to address this challenge by precisely mapping out the three-dimensional atomic positions at the grain boundaries for the first time.”

    The researchers then used the three-dimensional coordinates of the atoms as inputs into quantum mechanics calculations to determine the magnetic properties of the iron-platinum nanoparticle. They observed abrupt changes in magnetic properties at the grain boundaries.

    “This work makes significant advances in characterization capabilities and expands our fundamental understanding of structure-property relationships, which is expected to find broad applications in physics, chemistry, materials science, nanoscience and nanotechnology,” Miao said.

    In the future, as the researchers continue to determine the three-dimensional atomic coordinates of more materials, they plan to establish an online databank for the physical sciences, analogous to protein databanks for the biological and life sciences. “Researchers can use this databank to study material properties truly on the single-atom level,” Miao said.

    Miao and his team also look forward to applying their method called GENFIRE (GENeralized Fourier Iterative Reconstruction) to biological and medical applications. “Our three-dimensional reconstruction algorithm might be useful for imaging like CT scans,” Miao said. Compared with conventional reconstruction methods, GENFIRE requires fewer images to compile an accurate three-dimensional structure.

    That means that radiation-sensitive objects can be imaged with lower doses of radiation.

    The study’s co-authors include Yongsoo Yang, Rui Xu, AJ Pryor, Li Wu and Jihan Zhou, all at UCLA; Mary Scott, Colin Ophus, and Peter Ercius of Lawrence Berkeley National Laboratory; Chien-Chun Chen of the National Sun Yat-sen University; Fan Sun and Hao Zeng of the University at Buffalo; Markus Eisenbach and Paul Kent of Oak Ridge National Laboratory; Wolfgang Theis of the University of Birmingham; and Renat Sabirianov of the University of Nebraska Omaha.

    This work was supported by the U.S. Department of Energy’s Office of Basic Energy Sciences (grants DE-SC0010378, DE-AC02—05CH11231 and DE-AC05-00OR22725) as well as the U.S. National Science Foundation’s Division of Materials Research (grants DMR-1548924 and DMR-1437263).

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    UC LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
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