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  • richardmitnick 4:13 pm on June 15, 2017 Permalink | Reply
    Tags: Barry Barish, Caltech, , Kip S. Thorne, LIGO Team Wins Princess of Asturias Award, The late Caltech professor of physics Ronald W. P. Drever   

    From Caltech: “LIGO Team Wins Princess of Asturias Award” 

    Caltech Logo

    Caltech

    Whitney Clavin
    (626) 395-1856
    wclavin@caltech.edu

    1
    Barry Barish and Kip Thorne of Caltech

    2
    Rainer Weiss of MIT

    Caltech scientists Barry Barish, the Ronald and Maxine Linde Professor of Physics, Emeritus, and Kip S. Thorne (BS ’62), the Richard P. Feynman Professor of Theoretical Physics, Emeritus, have been awarded the 2017 Princess of Asturias Award for Technical and Scientific Research, along with Rainer Weiss of MIT and the entire LIGO Scientific Collaboration (LSC), a body of more than 1,000 international scientists who perform LIGO research. Past winners of the award in this category include Peter Higgs, François Englert and CERN (the European Organization for Nuclear Research), and Stephen Hawking. The prize consists a Joan Miró sculpture symbolizing the award and a cash prize of 50,000 euros (about 56,000 U.S. dollars).

    Thorne and Weiss, together with the late Caltech professor of physics Ronald W. P. Drever,

    4
    Ronald W. P. Drever

    are the founders of LIGO, the Laser Interferometer Gravitational-wave Observatory, which made history in 2016 when the LIGO team announced the first direct observation of gravitational waves—ripples in space and time predicted by Einstein 100 years earlier.

    Barish was the principal investigator for LIGO from 1994 to 2005, and director of the LIGO Laboratory from 1997 until 2006. He led LIGO through its final design stages and, under his leadership, the project was funded by the National Science Foundation and construction of the interferometers was completed. In 1997, he established the LSC, which continues to detect gravitational waves with LIGO.


    Caltech/MIT Advanced aLigo Hanford, WA, USA installation


    Caltech/MIT Advanced aLigo detector installation Livingston, LA, USA

    Cornell SXS, the Simulating eXtreme Spacetimes (SXS) project


    Gravitational waves. Credit: MPI for Gravitational Physics/W.Benger-Zib

    ESA/eLISA the future of gravitational wave research

    The Princess of Asturias Awards have been presented every year since 1981 by H. M. King Felipe of Spain. They come in eight different categories, from arts to international cooperation. Past recipients in all categories include Nelson Mandela, Arthur Miller, Susan Sontag, Doris Lessing, David Attenborough, Francis Ford Coppola, the Gates Foundation, and many more.

    See the full article here .

    Please help promote STEM in your local schools.

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    Stem Education Coalition

    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.”

    Caltech campus

     
  • richardmitnick 5:08 pm on June 12, 2017 Permalink | Reply
    Tags: , Caltech, , Researchers Find a Surprise Just Beneath the Surface in Carbon Dioxide Experiment   

    From LBNL: “Researchers Find a Surprise Just Beneath the Surface in Carbon Dioxide Experiment” 

    Berkeley Logo

    Berkeley Lab

    Caltech

    June 12, 2017
    Glenn Roberts Jr.
    geroberts@lbl.gov
    (510) 486-5582

    Berkeley Lab, Caltech team combines theory, X-ray experiments to explain what’s at work in copper catalyst

    1
    Scientists are seeking ways to reduce environmentally harmful levels of carbon dioxide from vehicle emissions and other sources by improving chemical processes that convert carbon dioxide gas into ethanol (molecular structure shown here) for use in liquid fuels, for example. X-ray experiments at Berkeley Lab have helped to show what’s at work in the early stages of chemical reactions that convert carbon dioxide and water into ethanol. (Credit: Wikimedia Commons)

    While using X-rays to study the early stages of a chemical process that can reformulate carbon dioxide into more useful compounds, including liquid fuels, researchers were surprised when the experiment taught them something new about what drives this reaction.

    An X-ray technique at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), coupled with theoretical work by a team at the California Institute of Technology, Pasadena (Caltech), revealed how oxygen atoms embedded very near the surface of a copper sample had a more dramatic effect on the early stages of the reaction with carbon dioxide than earlier theories could account for.

    This information could prove useful in designing new types of materials to further enhance reactions and make them more efficient in converting carbon dioxide into other products. Large concentrations of carbon dioxide are harmful to health and the environment, so researchers have been pursuing ways to remove it from the atmosphere and safely store it or chemically convert it into more beneficial forms.

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    This false-color scanning electron microscopy image shows microscopic details on the surface of a copper foil that was used as a catalyst in a chemical reaction studied at Berkeley Lab’s Advanced Light Source [ALS]. The scale bar represents 50 microns, or millionths of a meter. (Credit: Berkeley Lab)

    LBNL/ALS

    To explain what was at work, the research team developed computer models, and revised existing theories to explain what they were witnessing in experiments. Their results were published online June 12 in the Proceedings of the National Academy of Sciences journal.

    Copper is a common catalyst – a material used to activate and speed up chemical reactions – and, although it is not efficient, it aids in the production of ethanol when exposed to carbon dioxide and water. In the studied reaction, the copper helps to chemically break down and reassemble carbon dioxide and water molecules into other molecules.

    “We found more than we thought we were going to find from this fundamental investigation,” said Ethan Crumlin, a scientist at Berkeley Lab’s Advanced Light Source (ALS) who co-led the study with Joint Center for Artificial Photosynthesis (JCAP) researchers Junko Yano, at Berkeley Lab, and William Goddard III, at Caltech.

    The ALS is an X-ray research facility known as a synchrotron that has dozens of experimental beam lines for exploring a wide range of microscopic properties in matter, and JCAP is focused on how to convert carbon dioxide, water, and sunlight into renewable fuels.

    “Having oxygen atoms just beneath the surface – a suboxide layer – is a critical aspect to this,” Crumlin said. The X-ray work brought new clarity in determining the right amount of this subsurface oxygen – and its role in interactions with carbon dioxide gas and water – to improve the reaction.

    “Understanding this suboxide layer, and the suboxide in contact with water, is integral in how water interacts with carbon dioxide” in this type of reaction, he added.

    Goddard and his colleagues at Caltech worked closely with Berkeley Lab researchers to develop and refine a quantum mechanics theory that fit the X-ray observations and explained the electronic structure of the molecules in the reaction.

    “This was a good looping, iterative process,” Crumlin said. “Just being curious and not settling for a simple answer paid off. It all started coming together as a cohesive story.”

    Goddard said, “This back-and forth between theory and experiment is an exciting aspect of modern research and an important part of the JCAP strategy to making fuels from carbon dioxide.” The Caltech team used computers to help understand how electrons and atoms rearrange themselves in the reaction.

    At Berkeley Lab’s ALS, researchers enlisted an X-ray technique known as APXPS (ambient pressure X-ray photoelectron spectroscopy as they exposed a thin foil sheet of a specially treated copper – known as Cu(111) – to carbon dioxide gas and added water at room temperature. In proceeding experiments they heated the sample slightly in oxygen to vary the concentration of embedded oxygen in the foil, and used X-rays to probe the early stages of how carbon dioxide and water synergistically react with different amounts of subsurface oxide at the surface of the copper.

    2
    In this atomic-scale illustration, trace amounts of oxygen (red) just beneath a copper (blue) surface, play a key role in driving a catalytic reaction in which carbon dioxide (black and red molecules) and water (red and white molecules) interact in the beginning stages of forming ethanol. Carbon dioxide molecules hover at the copper surface and then bend to accept hydrogen atoms from the water molecules. X-ray experiments at Berkeley Lab’s Advanced Light Source [ALS] helped researchers to understand the role of subsurface oxygen in this process. (Credit: Berkeley Lab)

    The X-ray studies, planned and performed by Marco Favaro, the lead author of the study, revealed how carbon dioxide molecules collide with the surface of the copper, then hover above it in a weakly bound state. Interactions with water molecules serve to bend the carbon dioxide molecules in a way that allows them to strip hydrogen atoms away from the water molecules. This process eventually forms ethanol, a type of liquid fuel.

    “The modest amount of subsurface oxygen helps to generate a mixture of metallic and charged copper that can facilitate the interaction with carbon dioxide and promote further reactions when in the presence of water,” Crumlin said.

    Copper has some shortcomings as a catalyst, Yano noted, and it is currently difficult to control the final product a given catalyst will generate.

    “If we know what the surface is doing, and what the model is for this chemical interaction, then there is a way to mimic this and improve it,” Yano said. The ongoing work may also help to predict the final output of a given catalyst in a reaction. “We know that copper works – what about different copper surfaces, copper alloys, or different types of metals and alloys?”

    [The question remains.]

    See the full article here .

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    A U.S. Department of Energy National Laboratory Operated by the University of California

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  • richardmitnick 4:07 pm on June 2, 2017 Permalink | Reply
    Tags: , , Caltech, Caltech Program Fosters Scientific Curiosity in Pasadena Unified Students, STEM IN ACTION AT CALTECH   

    From Caltech: “Caltech Program Fosters Scientific Curiosity in Pasadena Unified Students” 

    Caltech Logo

    Caltech

    06/01/2017
    Jon Nalick

    [STEM IN ACTION AT CALTECH]

    1
    First-year geophysics graduate student Celeste Labedz shows off the results of her comet-making demonstration at a May 18 Science Night event at Field Elementary School in Pasadena. Credit: Caltech

    Eye-catching demonstrations include levitating magnets, jets of flame, and steaming hunks of ice

    As a gaggle of wide-eyed elementary school students crowd in for a view, first-year geophysics graduate student Celeste Labedz plunges her gloved hands into a basin overflowing with carbon dioxide fog.

    With the children’s help moments earlier, she had combined ingredients including water and dry ice to demonstrate how comets form. Now she pulls out the finished product: a fist-sized chunk of ice flecked with dirt and trailing streamers of white mist.

    “Whoa!” one student cries. “Can we make another one?”

    Labedz’s visit to Field Elementary School in Pasadena on May 18 was part of the Science Night program that brings more than 30 Caltech volunteers—undergraduate, graduate, and postdoctoral scholars in physics, chemistry, biology, geology, astronomy, and engineering—to conduct science demonstrations for students at 11 schools across Pasadena and the San Gabriel Valley.

    Started in 2013, the program originally targeted three area schools, but grew rapidly as parents and teachers spread the word about the events, and more schools invited Caltech to partner with them, says Mitch Aiken, associate director for educational outreach in Caltech’s Center for Teaching, Learning, and Outreach.

    Aiken says the program helps expand Catech’s community involvement and provides benefits not only to local schools and their students, but also to the Institute and its students. “Through these events, our students and researchers are contributing to elevating overall science literacy while improving their own ability to explain complex topics to diverse audiences. That’s critical to their success as they prepare for careers in industry, research, and academia.”

    More than 200 parents and students attended the recent event, which also featured hands-on demonstrations of gyroscopes, super-cooled magnets, and gravity-wave detectors.

    “Many parents and students told me this was the best night of the year,” says Daniel Bagby, principal of Field Elementary. “The presenters were so passionate about their field—and it was contagious. Students wanted to show me what they were learning and the sheer joy they were experiencing was truly palpable.”

    Arian Jadbabaie, a first-year physics graduate student who says he volunteers for Science Night about twice a month, spent the evening at Field demonstrating how gyroscopes work. Having visitors stand atop a spinnable disk, he invited them to grip a bike tire by handles attached to the sides its center axis. With the wheel spinning, participants tilted it right and left and suddenly found themselves turning on the disk, frequently prompting surprised laughter.

    “My favorite part of the demonstrations is the look of amazement on the kids’ faces when they see how the world is so much stranger than what they’ve seen or imagined,” he says. “In those moments, I feel like I’m on the same level as they are, regardless of what additional technical knowledge I might have.”

    Taking a break from her comet-making demonstration, Labedz agrees: “When kids are excited about what they’re hearing, you can see it. Sometimes they can’t keep it to themselves and start bouncing around. It’s awesome to see that learning can have that kind of effect on a kid.”

    See the full article here .

    Please help promote STEM in your local schools.

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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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  • richardmitnick 12:21 pm on May 28, 2017 Permalink | Reply
    Tags: , , Caltech, W. M. Keck Foundation, W. M. Keck Jr. Center dedication   

    From Caltech: “Caltech’s Keck Center Rededicated to Honor Former Trustee W. M. Keck Jr.” 

    Caltech Logo

    Caltech

    May 12, 2017

    1
    Caltech President Thomas Rosenbaum (left) and members of the Keck family—(from left) T. J. Keck, Robert Day, Stephen Keck, and William Keck, III—rededicate the W. M. Keck Jr. Center.

    On May 12, 2017, President Thomas F. Rosenbaum hosted a luncheon and a ceremony renaming Caltech’s Keck Center to celebrate the legacy of W. M. “Bill” Keck Jr. and Caltech’s longstanding partnership with the W. M. Keck Foundation and Superior Oil Company, both founded by Keck Jr.’s father. Keck Jr. served on the Caltech Board of Trustees from 1961 until his death in 1982 and was a key member of the Investment Committee during most of his tenure on the board.

    “It’s been a great partnership over the years between the Keck family and Caltech,” said Robert Day, who has been the chairman and CEO of the W. M. Keck Foundation for over 20 years and is the nephew of Keck Jr. “I’m very proud of this day; it’s a wonderful thing.”

    “John Lennon rightly remarked that ‘a dream you dream alone is only a dream. A dream you dream together is reality.’ This rededication of the Keck Center makes very real the continuing partnership, this continuing realized dream between the Keck family, the Keck Foundation, and Caltech,” said Thomas F. Rosenbaum, Caltech’s Sonja and William Davidow Presidential Chair and Professor of Physics, at the event. “The man whose vision and support has allowed us to dream is Robert Day.”

    A campus landmark, the W. M. Keck Jr. Center combines the historic Tolman/Bacher House with a modern conference facility, providing a meeting space for the Caltech Board of Trustees and other distinguished campus guests as well as a home for the Keck Institute for Space Studies (KISS). Established in 2008 with initial funding from the W. M. Keck Foundation and support from NASA’s Jet Propulsion Laboratory (JPL), KISS was created to develop revolutionary concepts and technologies for future space missions by taking advantage of opportunities for increased collaboration between researchers on campus and at JPL. The institute has achieved exciting successes in the development of new planetary, Earth, and astrophysics space mission concepts and technology, including designing a manned mission to an asteroid in lunar orbit, planning for a mission to one of Mars’s moons, and playing a role in the Curiosity rover’s ability to determine the age of a rock on Mars for the first time.

    The rededication of the Keck Center, originally named for W. M. Keck Sr., honors Keck Jr.’s service to the Institute. Through his personal philanthropic investments, he provided support for Caltech graduate housing in the early 1960s. Built in 1961 on Holliston Avenue, the three-story Keck Graduate House contained 53 single rooms and housed students until the 1990s. Keck Jr. also made substantial gifts to the Keck Presidential Fund, which helped advance presidential priorities, including the recruitment and retention of preeminent scholars.

    The naming also recognizes Keck Jr.’s involvement as a director of the Keck Foundation in the organization’s longstanding commitment to Caltech. Established using proceeds from Superior Oil, the W. M. Keck Foundation has been a significant supporter of the Institute, with the organization’s first gift providing funds for the W. M. Keck Engineering Laboratories in 1959. Including that first gift, the foundation has supported facilities and programs ranging from the W. M. Keck Foundation Professorship in the Division of Geological and Planetary Sciences to the W. M. Keck Observatory on top of the Mauna Kea volcano on the island of Hawaii. The Keck Observatory has been at the cutting edge of scientific exploration for the past two decades in making major discoveries that have broadened our understanding of the universe. We now have an opportunity to expand our window on the universe using new instruments developed at Caltech and the Keck telescopes will continue to play key roles in the search for biosignatures beyond our solar system.

    The lunch program on May 12 brought together Keck family members, Caltech trustees, and Institute leadership. Also in attendance were faculty members involved in KISS, such as director Tom Prince, professor of physics at Caltech, and Edward Stone, David Morrisroe Professor of Physics and vice provost for special projects.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    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.”

    Caltech campus

     
  • richardmitnick 3:29 pm on May 25, 2017 Permalink | Reply
    Tags: , , Caltech, , Fertilizer research, Nitrogen fixation   

    From Caltech: “Nitrogen Fixation Research Could Shed Light on Biological Mystery” 

    Caltech Logo

    Caltech

    05/25/2017

    Emily Velasco
    626-395-6487
    evelasco@caltech.edu

    1
    Fertilizer is applied to an agricultural field. Credit: Credit: SoilScience.info (CC BY 2.0)

    New Process Could Make Fertilizer Production More Sustainable

    Inspired by a natural process found in certain bacteria, a team of Caltech researchers is inching closer to a new method for producing fertilizer that could some day hold benefits for farmers—particularly in the developing world—while also shedding light on a biological mystery.

    Fertilizers are chemical sources of nutrients that are otherwise lacking in soil. Most commonly, fertilizers supply the element nitrogen, which is essential for all living things, as it is a fundamental building block of DNA, RNA, and proteins. Nitrogen gas is very abundant on Earth, making up 78 percent of our atmosphere. However, most organisms cannot use nitrogen in its gaseous form.

    To make nitrogen usable, it must be “fixed”—turned into a form that can enter the food chain as a nutrient. There are two primary ways that can happen, one natural and one synthetic.

    Nitrogen fixation occurs naturally due to the action of microbes that live in nodules on plant roots. These organisms convert nitrogen into ammonia through specialized enzymes called nitrogenases. The ammonia these nitrogen-fixing organisms create fertilizes plants that can then be consumed by animals, including humans. In a 2008 paper appearing in the journal Nature Geoscience, a team of researchers estimated that naturally fixed nitrogen provides food for roughly half of the people living on the planet.

    The other half of the world’s food supply is sustained through artificial nitrogen fixation and the primary method for doing this is the Haber-Bosch process, an industrial-scale reaction developed in Germany over 100 years ago. In the process, hydrogen and nitrogen gases are combined in large reaction vessels, under intense pressure and heat in the presence of a solid-state iron catalyst, to form ammonia.

    “The gases are pressurized up to many hundreds of atmospheres and heated up to several hundred degrees Celsius,” says Caltech’s Ben Matson, a graduate student in the lab of Jonas C. Peters, Bren Professor of Chemistry and director of the Resnick Sustainability Institute. ” With the iron catalyst used in the industrial process, these extreme conditions are required to produce ammonia at suitable rates.”

    In a recent paper appearing in ACS Central Science, Matson, Peters, and their colleagues describe a new way of fixing nitrogen that’s inspired by how microbes do it.

    Nitrogenases consist of seven iron atoms surrounded by a protein skeleton. The structure of one of these nitrogenase enzymes was first solved by Caltech’s Douglas Rees, the Roscoe Gilkey Dickinson Professor of Chemistry. The researchers in Peters’ lab have developed something similar to a bacterial nitrogenase, albeit much simpler—a molecular scaffolding that surrounds a single iron atom.

    The molecular scaffolding was first developed in 2013 and, although the initial design showed promise in fixing nitrogen, it was unstable and inefficient. The researchers have improved its efficiency and stability by tweaking the chemical bath in which the fixation reaction occurs, and by chilling it to approximately the temperature of dry ice (-78 degrees Celsius). Under these conditions, the reaction converts 72 percent of starting material into ammonia, a big improvement over the initial method, which only converted 40 percent of the starting material into ammonia and required more energy input to do so.

    Matson, Peters, and colleagues say their work holds the potential for two major benefits:

    • Ease of production: Because the technology being developed does not require high temperatures or pressures, there is no need for the large-scale industrial infrastructure required for the Haber-Bosch process. This means it might some day be possible to fix nitrogen in smaller facilities located closer to where crops are grown.

    “Our work could help to inspire new technologies for fertilizer production,” says Trevor del Castillo, a Caltech graduate student and co-author of the paper. “While this type of a technology is unlikely to displace the Haber-Bosch process in the foreseeable future, it could be highly impactful in places that that don’t have a very stable energy grid, but have access to abundant renewable energy, such as the developing world. There’s definitely room for new technology development here, some sort of ‘on demand’ solar-, hydroelectric-, or wind-powered process.”

    • Understanding natural nitrogen fixation: The nitrogenase enzyme is complicated and finicky, not working if the ambient conditions are not right, which makes it difficult to study. The new catalyst, on the other hand, is relatively simple. The team believes that their catalyst is performing fixation in a conceptually similar way as the enzyme, and that its relative simplicity will make it possible to study fixation reactions in the lab using modern spectroscopic techniques.

    “One fascinating thing is that we really don’t know, on a molecular level, how the nitrogenase enzyme in these bacteria actually turns nitrogen into ammonia. It’s a large unanswered question,” says graduate student Matthew Chalkley, also a co-author on the paper.

    Peters says their research into this catalyst has already given them a deeper understanding of what is happening during a nitrogen-fixing reaction.

    “An advantage of our synthetic iron nitrogenase system is that we can study it in great detail,” he says. “Indeed, in addition to significantly improving the efficiency of this new catalyst for nitrogen fixation, we have made great progress in understanding, at the atomic level, the critical bond-breaking and making-steps that lead to ammonia synthesis from nitrogen.”

    If processes of this type can be further refined and their efficiency increased, Peters adds, they may have applications outside of fertilizer production as well.

    “If this can be achieved, distributed solar-powered ammonia synthesis can become a reality. And not just as a fertilizer source, but also as an alternative, sustainable, and storable chemical fuel,” he says.

    See the full article here .

    Please help promote STEM in your local schools.

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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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  • richardmitnick 2:42 pm on May 24, 2017 Permalink | Reply
    Tags: , Caltech, , , New imaging technique aims to ensure surgeons completely remove cancer,   

    From Wash U: “New imaging technique aims to ensure surgeons completely remove cancer” 

    Wash U Bloc

    Washington University in St.Louis

    Caltech Logo

    Caltech

    May 17, 2017
    Tamara Bhandari
    tbhandari@wustl.edu

    1
    A new imaging technique based on light and sound produces images doctors can use to distinguish cancerous breast tissue (below the dotted blue line) from normal tissue more quickly than is currently possible. Pathologists routinely inspect surgical specimens to make sure all cancerous tissue has been removed. The new technique (right) produces images as detailed and accurate as traditional methods (left), but in far less time. The researchers are working to make the technique fast enough to be used during a surgery, so patients don’t have to return for a second surgery. (Image: Terence T.W. Wong)

    Of the quarter-million women diagnosed with breast cancer every year in the United States, about 180,000 undergo surgery to remove the cancerous tissue while preserving as much healthy breast tissue as possible.

    However, there’s no accurate method to tell during surgery whether all of the cancerous tissue has been successfully removed. The gold-standard analysis takes a day or more, much too long for a surgeon to wait before wrapping up an operation. As a result, about a quarter of women who undergo lumpectomies receive word later that they will need a second surgery because a portion of the tumor was left behind.

    Now, researchers at Washington University School of Medicine in St. Louis and California Institute of Technology report that they have developed a technology to scan a tumor sample and produce images detailed and accurate enough to be used to check whether a tumor has been completely removed.

    Called photoacoustic imaging, the new technology takes less time than standard analysis techniques. But more work is needed before it is fast enough to be used during an operation.

    The research is published May 17 in Science Advances.

    “This is a proof of concept that we can use photoacoustic imaging on breast tissue and get images that look similar to traditional staining methods without any sort of tissue processing,” said Deborah Novack, MD, PhD, an associate professor of medicine, and of pathology and immunology, and a co-senior author on the study.

    The researchers are working on improvements that they expect will bring the time needed to scan a specimen down to 10 minutes, fast enough to be used during an operation. The current gold-standard method of analysis, which is based on preserving the tissue and then staining it to make the cells easier to see, hasn’t gotten any faster since it was first developed in the mid-20th century.

    For solid tumors in most parts of the body, doctors use a technique known as a frozen section to do a quick check of the excised lump during the surgery. They look for a thin rim of normal cells around the tumor. Malignant cells at the margins suggest the surgeon missed some of the tumor, increasing the chances that the disease will recur.

    But frozen sections don’t work well on fatty specimens like those from the breast, so the surgeon must finish a breast lumpectomy without knowing for sure how successful it was.

    “Right now, we don’t have a good method to assess margins during breast cancer surgeries,” said Rebecca Aft, MD, PhD, a professor of surgery and a co-senior author on the study. Aft, a breast cancer surgeon, treats patients at Siteman Cancer Center at Barnes-Jewish Hospital and Washington University School of Medicine.

    Currently, after surgery a specimen is sent to a pathologist, who slices it, stains it and inspects the margins for malignant cells under a microscope. Results are sent back to the surgeon within a few days.

    To speed up the process, the researchers took advantage of a phenomenon known as the photoacoustic effect. When a beam of light of the right wavelength hits a molecule, some of the energy is absorbed and then released as sound in the ultrasound range. These sound waves can be detected and used to create an image.

    “All molecules absorb light at some wavelength,” said co-senior author Lihong Wang, who conducted the work when he was a professor of biomedical engineering at Washington University’s School of Engineering & Applied Science. He is now at Caltech. “This is what makes photoacoustic imaging so powerful. Essentially, you can see any molecule, provided you have the ability to produce light of any wavelength. None of the other imaging technologies can do that. Ultrasound will not do that. X-rays will not do that. Light is the only tool that allows us to provide biochemical information.”

    The researchers tested their technique by scanning slices of tumors removed from three breast cancer patients. For comparison, they also stained each specimen according to standard procedures.

    The photoacoustic image matched the stained samples in all key features. The architecture of the tissue and subcellular detail such as the size of nuclei were clearly visible.

    “It’s the pattern of cells – their growth pattern, their size, their relationship to one another – that tells us if this is normal tissue or something malignant,” Novack said. “Overall, the photoacoustic images had a lot of the same features that we see with standard staining, which means we can use the same criteria to interpret the photoacoustic imaging. We don’t have to come up with new criteria.”

    Having established that photoacoustic techniques can produce usable images, the researchers are working on reducing the scanning time.

    “We expect to be able to speed up the process,” Wang said. “For this study, we had only a single channel for emitting light. If you have multiple channels, you can scan in parallel and that reduces the imaging time. Another way to speed it up is to fire the laser faster. Each laser pulse gives you one data point. Faster pulsing means faster data collection.”

    Aft, Novack and Wang are applying for a grant to build a photoacoustic imaging machine with multiple channels and fast lasers.

    “One day we think we’ll be able to take a specimen straight from the patient, plop it into the machine in the operating room and know in minutes whether we’ve gotten all the tumor out or not,” Aft said. “That’s the goal.”

    This work was supported by the National Institutes of Health, grant number DP1 EB016986 and R01 CA186567, and by Washington University’s Siteman Cancer Center’s 2014 Research Development Award.

    See the full article here .

    Please help promote STEM in your local schools.

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    Stem Education Coalition

    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.”


    Caltech campus

    Wash U campus
    Wash U campus

    Washington University’s mission is to discover and disseminate knowledge, and protect the freedom of inquiry through research, teaching, and learning.

    Washington University creates an environment to encourage and support an ethos of wide-ranging exploration. Washington University’s faculty and staff strive to enhance the lives and livelihoods of students, the people of the greater St. Louis community, the country, and the world.

     
  • richardmitnick 8:04 am on April 23, 2017 Permalink | Reply
    Tags: , Caltech, New Quantum Liquid Crystals May Play Role in Future of Computers   

    From Caltech: “New Quantum Liquid Crystals May Play Role in Future of Computers” 

    Caltech Logo

    Caltech

    04/20/2017
    Whitney Clavin
    (626) 395-1856
    wclavin@caltech.edu

    1
    These images show light patterns generated by a rhenium-based crystal using a laser method called optical second-harmonic rotational anisotropy. At left, the pattern comes from the atomic lattice of the crystal. At right, the crystal has become a 3-D quantum liquid crystal, showing a drastic departure from the pattern due to the atomic lattice alone.
    Credit: Hsieh Lab/Caltech

    Physicists at the Institute for Quantum Information and Matter at Caltech have discovered the first three-dimensional quantum liquid crystal—a new state of matter that may have applications in ultrafast quantum computers of the future.

    “We have detected the existence of a fundamentally new state of matter that can be regarded as a quantum analog of a liquid crystal,” says Caltech assistant professor of physics David Hsieh, principal investigator on a new study describing the findings in the April 21 issue of Science. “There are numerous classes of such quantum liquid crystals that can, in principle, exist; therefore, our finding is likely the tip of an iceberg.”

    Liquid crystals fall somewhere in between a liquid and a solid: they are made up of molecules that flow around freely as if they were a liquid but are all oriented in the same direction, as in a solid. Liquid crystals can be found in nature, such as in biological cell membranes. Alternatively, they can be made artificially—such as those found in the liquid crystal displays commonly used in watches, smartphones, televisions, and other items that have display screens.

    In a “quantum” liquid crystal, electrons behave like the molecules in classical liquid crystals. That is, the electrons move around freely yet have a preferred direction of flow. The first-ever quantum liquid crystal was discovered in 1999 by Caltech’s Jim Eisenstein, the Frank J. Roshek Professor of Physics and Applied Physics. Eisenstein’s quantum liquid crystal was two-dimensional, meaning that it was confined to a single plane inside the host material—an artificially grown gallium-arsenide-based metal. Such 2-D quantum liquid crystals have since been found in several more materials including high-temperature superconductors. These are materials that conduct electricity with zero resistance at around –150 degrees Celsius, which is warmer than operating temperatures for traditional superconductors.

    John Harter, a postdoctoral scholar in the Hsieh lab and lead author of the new study, explains how 2-D quantum liquid crystals behave in strange ways. “Electrons living in this flatland collectively decide to flow preferentially along the x-axis rather than the y-axis even though there’s nothing to distinguish one direction from the other,” he says.

    Now Harter, Hsieh, and their colleagues at Oak Ridge National Laboratory and the University of Tennessee have discovered the first 3-D quantum liquid crystal. Compared to a 2-D quantum liquid crystal, the 3-D version is even more bizarre. Here, the electrons not only make a distinction between the x-, y-, and z-axes, but they also have different magnetic properties depending on whether they flow forward or backward on a given axis.

    “Running an electrical current through these materials transforms them from nonmagnets into magnets, which is highly unusual,” says Hsieh. “What’s more, in every direction that you can flow current, the magnetic strength and magnetic orientation changes. Physicists say that the electrons ‘break the symmetry’ of the lattice.”

    Harter hit upon the discovery serendipitously. He was originally interested in studying the atomic structure of a metal compound based on the element rhenium. In particular, he was trying to characterize the structure of the crystal’s atomic lattice using a technique called optical second-harmonic rotational anisotropy. In these experiments, laser light is fired at a material, and light with twice the frequency is reflected back out. The pattern of emitted light contains information about the symmetry of the crystal. The patterns measured from the rhenium-based metal were very strange—and could not be explained by the known atomic structure of the compound.

    “At first, we didn’t know what was going on,” Harter says. The researchers then learned about the concept of 3-D quantum liquid crystals, developed by Liang Fu, a physics professor at MIT. “It explained the patterns perfectly. Everything suddenly made sense,” Harter says.

    The researchers say that 3-D quantum liquid crystals could play a role in a field called spintronics, in which the direction that electrons spin may be exploited to create more efficient computer chips. The discovery could also help with some of the challenges of building a quantum computer, which seeks to take advantage of the quantum nature of particles to make even faster calculations, such as those needed to decrypt codes. One of the difficulties in building such a computer is that quantum properties are extremely fragile and can easily be destroyed through interactions with their surrounding environment. A technique called topological quantum computing—developed by Caltech’s Alexei Kitaev, the Ronald and Maxine Linde Professor of Theoretical Physics and Mathematics—can solve this problem with the help of a special kind of superconductor dubbed a topological superconductor.

    “In the same way that 2-D quantum liquid crystals have been proposed to be a precursor to high-temperature superconductors, 3-D quantum liquid crystals could be the precursors to the topological superconductors we’ve been looking for,” says Hsieh.

    “Rather than rely on serendipity to find topological superconductors, we may now have a route to rationally creating them using 3-D quantum liquid crystals” says Harter. “That is next on our agenda.”

    The Science study, titled A parity-breaking electronic nematic phase transition in the spin-orbit coupled metal Cd2Re2O7, was funded by the U.S. Department of Energy, the U.S. Army Research Office’s Defense University Research Instrumentation Program, the Alfred P. Sloan Foundation, the National Science Foundation, and the Gordon and Betty Moore Foundation.

    See the full article here .

    Please help promote STEM in your local schools.

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    Stem Education Coalition

    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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  • richardmitnick 12:34 pm on April 14, 2017 Permalink | Reply
    Tags: , , , Caltech, , ,   

    From Caltech: “Keck Cosmic Web Imager Achieves ‘First Light'” 

    Caltech Logo

    Caltech

    04/14/2017

    Whitney Clavin
    (626) 395-1856
    wclavin@caltech.edu

    1
    Keck Observatory

    A Caltech-built instrument designed to study the mysteries of the cosmic web—streams of gas connecting galaxies—has captured its first image, an event astronomers call “first light.” The instrument, called the Keck Cosmic Web Imager, or KCWI, was recently installed on the W. M. Keck Observatory in Hawaii.

    2
    Hector Rodriguez, senior mechanical technician, works on the Keck Cosmic Web Imager in a clean room at Caltech. Credit: Caltech

    KCWI captures highly detailed spectral images of cosmic objects to reveal their temperature, motion, density, mass, distance, chemical composition, and more. The instrument is designed to study the wispy cosmic web; it will also observe many other astronomical phenomena, including young stars, evolved stars, supernovas, star clusters, and galaxies.

    “I’m incredibly excited. These moments happen only a few times in one’s life as a scientist,” says principal investigator Christopher Martin, professor of physics at Caltech. “To take a powerful new instrument, a tool for looking at the universe in a completely novel way, and install it at the greatest observatory in the world is a dream for an astronomer. This is one of the best days of my life.”

    Martin and his Caltech team, in collaboration with scientists at UC Santa Cruz and with industrial partners, designed and built the 5-ton instrument—about the size of an ice cream truck. It was then shipped from California to Hawaii on January 12. Since then, Keck Observatory’s team has been working diligently to install and test KCWI on Keck II, one of the twin 10-meter Keck Observatory telescopes.

    “KCWI will really raise the bar in terms of Keck Observatory’s capabilities,” says Anne Kinney, chief scientist at Keck Observatory. “I think it will become the most popular instrument we have, because it will be able to do a great breadth of science, increasing our ability to understand and untangle the effects of dark matter in galaxy formation.”

    The W. M. Keck Observatory is a private 501(c)3 nonprofit organization and a scientific partnership of Caltech, the University of California, and NASA.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    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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  • richardmitnick 12:51 pm on March 18, 2017 Permalink | Reply
    Tags: A Humanist Among the Scientists: A Conversation with Maura Dykstra, Caltech   

    From Caltech: “A Humanist Among the Scientists: A Conversation with Maura Dykstra” 

    Caltech Logo

    Caltech

    03/17/2017
    Lori Dajose
    (626) 395-1217
    ldajose@caltech.edu

    1
    Maura Dykstra. Credit: Caltech

    When you walk into Maura Dykstra’s new office at Caltech, one of the first things you notice is a table covered in scrolls, brushes, and calligraphic Chinese characters. For Dykstra, a new assistant professor of history, calligraphy is not just a hobby—it is practice to help her read and analyze historical documents. Dykstra is a historian studying the policies, government, and everyday life in China during the last dynasty—from the 17th to the early 20th century. We sat down with her to discuss Chinese history, calligraphy, her hobbies, and the importance of teaching history to science students.

    What is the focus of your research?

    I’m interested in how people are governed and how policy decisions—made in order to help society flourish and keep people from doing bad things—produce opportunities for cheating, produce opportunities for beauty, and produce unexpected consequences. I’m interested in how all of the institutions that we live with today are a combination of incredible human invention and sometimes strange circumstance.

    What led you to study history?

    I dropped out of high school when I was 15—partly because I hated history. I hated the expectation that I was supposed to listen to what teachers were saying and look for clues about how they understood reality in order to present those things back to them as answers about universal truths. I really didn’t like this vision of how knowledge worked. It involved generalizations about complicated historical truths and it demanded the student’s acquiescence to the instructor’s view of how the world worked. It didn’t encourage the student to wonder about the world of the past or the future.

    My mother’s condition for letting me drop out was that I continue my schooling, so I took some classes at City College of San Francisco. I dabbled in philosophy and film, only to drop out after three semesters to join an internet company back when that was the fashionable thing to do. I taught myself programming and HTML, and dreamed about the way that these new tools of communication and exchange would revolutionize the world by facilitating the transfer of information.

    After the September 11 terrorist attacks, that new world I had expected to emerge seemed far away. Foolish, even. I realized that I wasn’t interested in spending the rest of my life chasing around people’s HTML problems. I was actually interested in trying to do something that would make the world a more bearable place for myself and for the other people around me. Something that could bring people closer together and allow them to express their differences in productive ways as a more immediate goal for those of us who had been dreaming of a global information society but woke up in a divided world.

    I went back to school to take some history classes out of curiosity and, in the course of doing that, I developed the conviction that history can actually help us solve problems today. History gives us a perspective on the questions of the present day that requires us to expand our point of view beyond the most obvious parameters. A careful attention to how things came to be imbues us with an appreciation for the possibilities of what might have been and opens us up to questions that people caught up in the current moment might forget to ask. I believe that historical inquiry can offer insight not only into specific problems in the current day but also into the assumptions behind those problems and the world that exists beyond them. I decided to commit myself to the study of history when I realized how powerfully it can redefine the way that we ask questions about our lives today.

    What’s it like to be a historian at Caltech?

    In general, the link between humanities learning and practical problems in the current day is an extremely tenuous and sometimes problematic one. The lessons that we learn from humanities are often several steps removed from current problems. The important thing becomes attention to how those intermediate steps between research and theory and then application both within and beyond the humanities disciplines can be navigated. What is uniquely wonderful about working at Caltech is that I get to be in the same place as people who are working on the problems of today and in a community where a conversation across disciplines is encouraged.

    If I am puzzling out a problem about contracts and the game theory around contract enforcement, or if I’m interested in the political implications of a certain legal system, or if I’m curious about information policies and their influence on democratic institutions, I can actually go find someone here who studies that subject. More likely than not they will agree that conversations about shared subjects across disciplinary boundaries are opportunities for exploration. The collaborative, cross-disciplinary profile of Caltech’s faculty makes these conversations not only possible, but genuinely exciting.

    Why is history important for STEM students?

    I believe the best way to contribute to the knowledge of this generation, and to make the best possible future for the world, is to expand our imagination of what’s possible. One of the things you often find in history is that people make choices that turn out to be not very beneficial for them because at the time they were facing a problem, they couldn’t imagine anything other than a binary option, or they couldn’t draw on other traditions and ways they translate into their own problem.

    It’s important for people who will go on to become political leaders or intellectual figures or innovators to understand some of the complexity involved in operating across systems with very distinct historical characteristics. I think many people who get involved in the humanities in general and in history in particular do it because they want to find a better way to have a conversation about things that matter with people they don’t already agree with. When we simply discuss the things that are in front of us with our own perspective as the guiding compass, we miss a lot of opportunities for thinking outside of ourselves.

    What do you like to do in your free time?

    There are all sorts of things I do to make sure that I don’t just stay in my head. In addition to doing calligraphy, I am a potter, so sometimes I do ceramics. I enjoy cooking. I am a fencer and a martial artist. When I was doing postdoctoral research at Harvard, I worked at a press that used 19th-century technology to print things. I learned how to set type. I learned how to carve plates to make intaglio prints.

    Of course, I love to travel. That’s one of the best parts of the job. I get to go all over the place chasing down materials. I get to visit all sorts of beautiful, interesting places. When you’re a historian, your laboratory is the world—and the more you study it, the more interesting it becomes.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    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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  • richardmitnick 10:14 am on March 16, 2017 Permalink | Reply
    Tags: , , Caltech, , Deep-sea corals, Desmophyllum dianthus, , Study: Cold Climates and Ocean Carbon Sequestration, Why the earth goes through periodic climate change   

    From Caltech: “Study: Cold Climates and Ocean Carbon Sequestration” 

    Caltech Logo

    Caltech

    03/14/2017

    Robert Perkins
    (626) 395-1862
    rperkins@caltech.edu

    1
    Tony Wang (left) and Jess Adkins (right) with samples of Desmophyllum dianthus fossils.

    Deep-sea corals reveal why atmospheric carbon was reduced during colder time periods

    We know a lot about how carbon dioxide (CO2) levels can drive climate change, but how about the way that climate change can cause fluctuations in CO2 levels? New research from an international team of scientists reveals one of the mechanisms by which a colder climate was accompanied by depleted atmospheric CO2 during past ice ages.

    The overall goal of the work is to better understand how and why the earth goes through periodic climate change, which could shed light on how man-made factors could affect the global climate.

    Earth’s average temperature has naturally fluctuated by about 4 to 5 degrees Celsius over the course of the past million years as the planet has cycled in and out of glacial periods. During that time, the earth’s atmospheric CO2 levels have fluctuated between roughly 180 and 280 parts per million (ppm) every 100,000 years or so. (In recent years, man-made carbon emissions have boosted that concentration up to over 400 ppm.)

    About 10 years ago, researchers noticed a close correspondence between the fluctuations in CO2 levels and in temperature over the last million years. When the earth is at its coldest, the amount of CO2 in the atmosphere is also at its lowest. During the most recent ice age, which ended about 11,000 years ago, global temperatures were 5 degrees Celsius lower than they are today, and atmospheric CO2 concentrations were at 180 ppm.

    Using a library of more than 10,000 deep-sea corals collected by Caltech’s Jess Adkins, an international team of scientists has shown that periods of colder climates are associated with higher phytoplankton efficiency and a reduction in nutrients in the surface of the Southern Ocean (the ocean surrounding the Antarctic), which is related to an increase in carbon sequestration in the deep ocean. A paper about their research appears the week of March 13 in the online edition of the Proceedings of the National Academy of Sciences.

    “It is critical to understand why atmospheric CO2 concentration was lower during the ice ages. This will help us understand how the ocean will respond to ongoing anthropogenic CO2 emissions,” says Xingchen (Tony) Wang, lead author of the study. Wang was a graduate student at Princeton while conducting the research in the lab of Daniel Sigman, Dusenbury Professor of Geological and Geophysical Sciences. He is now a Simons Foundation Postdoctoral Fellow on the Origins of Life at Caltech.

    There is 60 times more carbon in the ocean than in the atmosphere—partly because the ocean is so big. The mass of the world’s oceans is roughly 270 times greater than that of the atmosphere. As such, the ocean is the greatest regulator of carbon in the atmosphere, acting as both a sink and a source for atmospheric CO2.

    Biological processes are the main driver of CO2 absorption from the atmosphere to the ocean. Just like photosynthesizing trees and plants on land, plankton at the surface of the sea turn CO2 into sugars that are eventually consumed by other creatures. As the sea creatures who consume those sugars—and the carbon they contain—die, they sink to the deep ocean, where the carbon is locked away from the atmosphere for a long time. This process is called the “biological pump.”

    A healthy population of phytoplankton helps lock away carbon from the atmosphere. In order to thrive, phytoplankton need nutrients—notably, nitrogen, phosphorus, and iron. In most parts of the modern ocean, phytoplankton deplete all of the available nutrients in the surface ocean, and the biological pump operates at maximum efficiency.

    However, in the modern Southern Ocean, there is a limited amount of iron—which means that there are not enough phytoplankton to fully consume the nitrogen and phosphorus in the surface waters. When there is less living biomass, there is also less that can die and sink to the bottom—which results in a decrease in carbon sequestration. The biological pump is not currently operating as efficiently as it theoretically could.

    To track the efficiency of the biological pump over the span of the past 40,000 years, Adkins and his colleagues collected more than 10,000 fossils of the coral Desmophyllum dianthus.

    Why coral? Two reasons: first, as it grows, coral accretes a skeleton around itself, precipitating calcium carbonate (CaCO3) and other trace elements (including nitrogen) out of the water around it. That process creates a rocky record of the chemistry of the ocean. Second, coral can be precisely dated using a combination of radiocarbon and uranium dating.

    “Finding a few centimeter-tall fossil corals 2,000 meters deep in the ocean is no trivial task,” says Adkins, Smits Family Professor of Geochemistry and Global Environmental Science at Caltech.

    Adkins and his colleagues collected coral from the relatively narrow (500-mile) gap known as the Drake Passage between South America and Antarctica (among other places). Because the Southern Ocean flows around Antarctica, all of its waters funnel through that gap—making the samples Adkins collected a robust record of the water throughout the Southern Ocean.

    Wang analyzed the ratios of two isotopes of nitrogen atoms in these corals – nitrogen-14 (14N, the most common variety of the atom, with seven protons and seven neutrons in its nucleus) and nitrogen-15 (15N, which has an extra neutron). When phytoplankton consume nitrogen, they prefer 14N to 15N. As a result, there is a correlation between the ratio of nitrogen isotopes in sinking organic matter (which the corals then eat as it falls to the seafloor) and how much nitrogen is being consumed in the surface ocean—and, by extension, the efficiency of the biological pump.

    A higher amount of 15N in the fossils indicates that the biological pump was operating more efficiently at that time. An analogy would be monitoring what a person eats in their home. If they are eating more of their less-liked foods, then one could assume that the amount of food in their pantry is running low.

    Indeed, Wang found that higher amounts of 15N were present in fossils corresponding to the last ice age, indicating that the biological pump was operating more efficiently during that time. As such, the evidence suggests that colder climates allow more biomass to grow in the surface Southern Ocean—likely because colder climates experience stronger winds, which can blow more iron into the Southern Ocean from the continents. That biomass consumes carbon, then dies and sinks, locking it away from the atmosphere.

    Adkins and his colleagues plan to continue probing the coral library for further details about the cycles of ocean chemistry changes over the past several hundred thousand years.

    The study is titled “Deep-sea coral evidence for lower Southern Ocean surface nitrate concentrations during the last ice age.” Coauthors include scientists from Caltech, Princeton University, Pomona College, the Max Planck Institute for Chemistry in Germany, University of Bristol, and ETH Zurich in Switzerland. This research was funded by the National Science Foundation, Princeton University, the European Research Council, and the Natural Environment Research Council.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    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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