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  • richardmitnick 11:42 am on May 18, 2020 Permalink | Reply
    Tags: "First Estimate of Sub-Seafloor Hydrogen Budget Sheds Light on a Hidden Biosphere", , Duke University   

    From Duke University: “First Estimate of Sub-Seafloor Hydrogen Budget Sheds Light on a Hidden Biosphere” 



    From Duke University

    1
    By providing the first estimate of how much hydrogen is available to fuel microbial life in the sunless sub-seafloor crust beneath the Mid-Ocean Ridge (MOR), a new Duke University-led study sheds light on one of Earth’s least understood biospheres.

    By providing the first estimate of how much hydrogen is available to fuel microbial life in the sunless sub-seafloor crust beneath the Mid-Ocean Ridge (MOR), a new Duke University-led study sheds light on one of Earth’s least understood biospheres.

    It may also help illuminate how similar conditions could support life in other extreme environments, from distant planets to early Earth itself.

    Most microbes use sunlight-powered photosynthesis to create organic matter. But chemosynthetic microbial communities living deep within the volcanic rock of Earth’s oceanic crust lack this energy source and use hydrogen, released as a free gas when water flows through the iron-rich rock, as their fuel to convert carbon dioxide into food.

    Scientists have known that life can thrive in the abyss since shortly after the discovery of the first deep-sea hydrothermal vents in 1977. But it wasn’t until 2013 that microbiologists discovered microbial communities living within volcanic rocks beneath the seafloor. That discovery sparked widespread scientific curiosity, not only due to the potential size of the newfound biosphere — the oceanic crust is several kilometers thick and covers 60% of Earth’s surface — but also because the extreme, oxygen-poor conditions found there are similar to those when life first began on Earth, a time when chemical energy may have been the only energy source available to fuel microbes’ metabolisms.

    “Until now, however, we had no good constraints on the overall size of these microbial communities or how much hydrogen they consume. This new study provides a first estimate and gives us new insights into the scope of these microbes’ impact on Earth’s climate and paleoclimate,” said Lincoln Pratson, Gendell Family Professor of Energy and Environment at Duke’s Nicholas School of the Environment.

    “It also gives us boundary conditions for what some of the earliest forms of life on Earth had to deal with, and for where you might look for life on other planets,” he said.

    The scientists published their peer-reviewed paper the week of May 11 in the Proceedings of the National Academy of Sciences.

    To conduct their study, they constructed a box model that assessed the total production of hydrogen gas (H2) from nine different geological sources within a nearly 30 million-square-kilometer corridor of oceanic crust centered on the Mid-Ocean Ridge. The corridor snakes along the ridge through all the world’s oceans and covers about 10% of the entire oceanic crust.

    The team also estimated how much of this hydrogen gas likely was being released into the ocean through seafloor hydrothermal vents, based on more than 500 measurements of water samples collected by other researchers on previous expeditions along the Mid-Ocean Ridge.

    “By subtracting the amount of gas being vented, which was roughly 20 million metric tons per year, from the amount being produced, which was roughly 30 million metric tons per year, we were left with around 10 million metric tons annually that are, presumably, being consumed by microbes within this strip of crust,” said lead author Stacey L. Worman, a former student of Pratson’s whose 2015 doctoral dissertation on hydrogen gas reserves beneath the Mid-Ocean Ridge provided the impetus for the new study.

    These numbers suggest that microbial communities play a significant role in helping regulate Earth’s global biogeochemistry, said Worman, who now works as a research analyst at Chevy Chase Trust in Bethesda, Md.

    “Microbes beneath the seafloor and in the dark ocean consume significant quantities of this reduced gas. Without these microbes consuming this highly diffusive gas, this geologically produced H2 could conceivably escape into the atmosphere,” she said.

    Such an input would represent a sizeable bump – about 10% – to the Earth’s current atmospheric hydrogen budget. Since hydrogen gas can hasten the build-up of greenhouse gases in the lower atmosphere, that could have a significant impact on global warming.

    On a global scale, the impact may be much larger, Pratson noted, since the remaining 90% of the ocean crust that was not included in this study may also have hydrogen production and consumption going on.

    “While our analysis estimates how much H2 might be consumed by the deep biosphere in the vicinity of the MOR, it’s unclear whether the size of the deep biosphere is limited by the availability of H2 or by other factors, such as temperature, nutrients, pressure, pH or even space,” Worman said. “Combining this study and future work on the H2 budget with other key constraints on life is a promising avenue for advancing our understanding of its origin and evolution here on Earth and for targeting where to search for life elsewhere in the universe.”

    Worman and Pratson conducted the study with Jeffrey A. Karson, Jessie Page Heroy Professor of Geology at Syracuse University, and William H. Schlesinger, James B. Duke Professor Emeritus of Biogeochemistry, former dean of Duke’s Nicholas School and president emeritus of the Cary Institute of Ecosystem Studies,

    CITATION: “Abiotic Hydrogen (H2) Sources and Sinks Near the Mid-Ocean Ridge (MOR) with Implications for the Subseafloor Biosphere,” Stacey L. Worman, Lincoln F. Pratson, Jeffrey A. Karson and William H. Schlesinger; May 11, 2020, Proceedings of the National Academy of Sciences. DOI: 10.1073/pnas.2002619117

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Younger than most other prestigious U.S. research universities, Duke University consistently ranks among the very best. Duke’s graduate and professional schools — in business, divinity, engineering, the environment, law, medicine, nursing and public policy — are among the leaders in their fields. Duke’s home campus is situated on nearly 9,000 acres in Durham, N.C, a city of more than 200,000 people. Duke also is active internationally through the Duke-NUS Graduate Medical School in Singapore, Duke Kunshan University in China and numerous research and education programs across the globe. More than 75 percent of Duke students pursue service-learning opportunities in Durham and around the world through DukeEngage and other programs that advance the university’s mission of “knowledge in service to society.”

     
  • richardmitnick 12:30 pm on April 13, 2020 Permalink | Reply
    Tags: "New handle for controlling electromagnetic properties could enable spintronic computing", , , , Duke University, ,   

    From Duke University via phys.org: “New handle for controlling electromagnetic properties could enable spintronic computing” 



    From Duke University

    via


    From phys.org

    April 13, 2020
    Ken Kingery

    1
    A large, perfect crystal of iron sulfide that was painstakingly grown for the research experiments probing the change of atomic vibrations across magnetic transition. Credit: Haidong Zhou, University of Tennessee.

    Materials scientists at Duke University have shown the first clear example that a material’s transition into a magnet can control instabilities in its crystalline structure that cause it to change from a conductor to an insulator.

    If researchers can learn to control this unique connection between physical properties identified in hexagonal iron sulfide, it could enable new technologies such as spintronic computing. The results appear April 13 in the journal Nature Physics.

    Commonly known as troilite, hexagonal iron sulfide can be found natively on Earth but is more abundant in meteorites, particularly those originating from the Moon and Mars. Rarely encountered in the Earth’s crust, most troilite on Earth is believed to have originated from space.

    Despite its relative rarity, troilite has been studied since 1862 without much fanfare. A recent theoretical paper, however, suggested that there might be novel physics at play between the temperatures of 289 and 602 degrees Fahrenheit—the temperature range at which troilite becomes both magnetic and an insulator.

    “The paper theorized that the way the atoms shift in their crystalline structure is impacting the mineral’s properties through a pretty complicated effect that hasn’t been seen before,” said Olivier Delaire, associate professor of mechanical engineering and materials science, physics and chemistry at Duke. “The most important aspect is this interaction between magnetic properties and atomic dynamics, which is a subject that has not been investigated a lot before but is opening up new possibilities in computing technologies.”

    To get to the heart of the material’s odd behavior, Delaire and his colleagues turned to Haidong Zhou, assistant professor of experimental condensed matter physics at the University of Tennessee, for the difficult task of growing perfect crystals of troilite. The researchers then took samples to Oak Ridge National Laboratory and Argonne National Laboratory to blast them with neutrons and x-rays, respectively.

    When particles such as neutrons or x-rays bounce off the atoms inside a material, researchers can take this scattering information to reconstruct its atomic structure and dynamics. Because neutrons have their own internal magnetic moment, they can also reveal the direction of each atom’s magnetic spin. But because neutrons interact weakly with atoms, x-rays are also very handy for resolving a material’s atomic structure and atomic vibrations in tiny crystals. The researchers compared results from the two different scans using quantum mechanical models created on a supercomputer at Lawrence Berkeley National Laboratory to make sure they understood what was happening.

    After watching the changes that occur through troilite’s phase transformations, the researchers discovered previously unseen mechanisms at work. At high temperatures, the magnetic spins of troilite atoms point in random directions, making the material non-magnetic. But once the temperature drops below 602 degrees Fahrenheit, the magnetic moments naturally align and a magnet is born.

    The alignment of those magnetic spins shifts the vibration dynamics of the atoms. That shift causes the entire crystalline atomic structure to deform slightly, which in turn creates a band gap that electrons cannot jump across. This causes the troilite to lose its ability to conduct electricity.

    “This is the first clear example that the alignment of magnetic spins can control the instabilities of a material’s crystal structure,” said Delaire. “And because these instabilities lead to a connection between the crystal’s magnetic and conductivity properties, this is the type of material that’s exciting in terms of enabling new types of devices.”

    The ability to tune a material’s magnetic state by applying electrical currents, and vice versa, would be essential for the realization of technologies such as spin electronics, Delaire said. Known as spintronics for short, this emerging field seeks to use an electron’s intrinsic spin and associated magnetic moment to store and manipulate data. Combined with an electron’s traditional role in computing, this would allow computer processors to become denser and more efficient.

    Through this paper, Delaire and his colleagues have identified the magnetic controls of the distortion mechanisms of the crystal structure, giving researchers a handle to manipulate one with the other. While that handle is currently based in temperature changes, the next step for researchers is to look at applying external magnetic fields to see how they might affect the material’s atomic dynamics.

    Whether or not troilite becomes the new silicon for the next generation of computing technology, Delaire says finding this unique mechanism in such a well-known material is a good lesson for the entire field.

    “It’s surprising that, even though you have a compound that is relatively simple, you can have this fancy mechanism that could end up enabling new technologies,” said Delaire. “In a sense, it’s a wakeup call that we need to reconsider some of the simpler materials to look for similar effects elsewhere.”

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition


    Younger than most other prestigious U.S. research universities, Duke University consistently ranks among the very best. Duke’s graduate and professional schools — in business, divinity, engineering, the environment, law, medicine, nursing and public policy — are among the leaders in their fields. Duke’s home campus is situated on nearly 9,000 acres in Durham, N.C, a city of more than 200,000 people. Duke also is active internationally through the Duke-NUS Graduate Medical School in Singapore, Duke Kunshan University in China and numerous research and education programs across the globe. More than 75 percent of Duke students pursue service-learning opportunities in Durham and around the world through DukeEngage and other programs that advance the university’s mission of “knowledge in service to society.”

     
  • richardmitnick 3:36 pm on February 14, 2020 Permalink | Reply
    Tags: "Dividing Lines — and Common Ground — Between Rural and Urban Voters on Environmental Policy", Climate change is a polarizing issue in rural America but there is a path forward that can win rural support., Duke University, Duke University’s Nicholas Institute for Environmental Policy Solutions, The urban/rural divide centers not on differences in how much people value environmental protection but on divergent views toward government regulation.   

    From Duke University: “Dividing Lines — and Common Ground — Between Rural and Urban Voters on Environmental Policy” 



    From Duke University

    February 13, 2020

    Jeremy Ashton,
    jeremy.ashton@duke.edu
    919.613.4361.

    Rural and urban Americans are divided in their views on the environment, but common ground does exist, says a new report led by Duke University’s Nicholas Institute for Environmental Policy Solutions.

    1

    “The urban/rural divide on the environment is real, but it centers not on differences in how much people value environmental protection but on divergent views toward government regulation,” said lead author Robert Bonnie, executive in residence at the Nicholas Institute and a former undersecretary for natural resources and environment at the U.S. Department of Agriculture. “Rural Americans, across party lines, are less supportive of governmental oversight on the environment than their urban/suburban counterparts.”

    The study [Nicholas Institute for Environmental Policy Solutions, Duke University] was conducted over two years by the Nicholas Institute with assistance from the University of Rhode Island, the University of Wyoming, Hart Research Associates and New Bridge Strategy. It involved extensive outreach to rural constituencies, including a national survey of more than 2,000 registered voters, focus groups with more than 125 rural voters and in-depth interviews with 36 rural leaders.

    Rural Americans have an outsized impact on national environmental policy, from strong representation in the halls of Congress to management of vast swaths of lands and watersheds, the authors note.

    Polling results indicated broad support for conservation and environmental protection among both rural and urban/suburban voters. The study also found rural voters to be relatively knowledgeable about environmental policies and the potential economic trade-offs that come with them.

    “Americans living in rural communities showed a powerful commitment to protecting the environment, motivated in large part by a strong place identity and desire to maintain local environmental resources for future generations,” said study co-author Emily Diamond, assistant professor at the University of Rhode Island.

    Rural voters significantly diverged from urban and suburban voters over attitudes toward federal regulation, the study found. In the polling, rural voters across political parties expressed more skepticism for government policies. Participants in focus group conversations often voiced strong support for conservation and environmental protection in the abstract but raised concerns about the impacts and effectiveness of specific policies.

    Climate change proved to be another dividing line between rural and urban/suburban voters.

    “Our focus groups and interviews echoed this sense that rural opposition to climate change policies may be tied to negative experiences they have had with other federal environmental regulations,” Diamond said.

    “Climate change is a polarizing issue in rural America, but there is a path forward that can win rural support,” Bonnie added. “Our study shows that engagement and collaboration with rural stakeholders will be important to winning over rural support.”

    There is no quick fix to bridging the urban/rural divide on environmental policies, the authors said. They recommend that policymakers, environmentalists and conservation groups engage more with rural communities when developing policies that could affect them. The authors also suggest federal policies — especially for addressing climate change — are more likely to gain rural voters’ support if they allow for state and local partnerships and collaboration with rural stakeholders.

    Other key recommendations include:

    Working with trusted messengers, such as farmers, ranchers, and cooperative extension services, to convey information about environmental policies to local stakeholders
    Improving scientific outreach to rural communities
    Offering opportunities to address environmental policy priorities in a way that is compatible with rural economies

    Support for the study was provided by the William and Flora Hewlett Foundation, the Wilburforce Foundation and the Rubenstein Fellows Academy at Duke University. The Nicholas Institute for Environmental Policy Solutions contributed seed funding through its Catalyst Program to get the project started. The full report, “Understanding Rural Attitudes Toward the Environment and Conservation in America,” is available at nicholasinstitute.duke.edu/publications/understanding-rural-attitudes-toward-environment-and-conservation-america.

    The study was led by Bonnie with co-authors Diamond and Elizabeth Rowe, a master of environmental management student at Duke’s Nicholas School of the Environment. Jay Campbell at Hart Research Associates and Lori Weigel at New Bridge Strategy conducted focus groups and polling for the study.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition


    Younger than most other prestigious U.S. research universities, Duke University consistently ranks among the very best. Duke’s graduate and professional schools — in business, divinity, engineering, the environment, law, medicine, nursing and public policy — are among the leaders in their fields. Duke’s home campus is situated on nearly 9,000 acres in Durham, N.C, a city of more than 200,000 people. Duke also is active internationally through the Duke-NUS Graduate Medical School in Singapore, Duke Kunshan University in China and numerous research and education programs across the globe. More than 75 percent of Duke students pursue service-learning opportunities in Durham and around the world through DukeEngage and other programs that advance the university’s mission of “knowledge in service to society.”

     
  • richardmitnick 9:21 am on January 18, 2020 Permalink | Reply
    Tags: "‘Melting Rock’ Models Predict Mechanical Origins of Earthquakes", , Duke University, , , ,   

    From Duke University: “‘Melting Rock’ Models Predict Mechanical Origins of Earthquakes” 


    From Duke University

    January 17, 2020
    Ken Kingery

    New model accurately predicts why and how friction drops as rocks slide past one another with greater speed and undergo a phase change.

    Engineers at Duke University have devised a model that can predict the early mechanical behaviors and origins of an earthquake in multiple types of rock. The model provides new insights into unobservable phenomena that take place miles beneath the Earth’s surface under incredible pressures and temperatures, and could help researchers better predict earthquakes—or even, at least theoretically, attempt to stop them.

    The results appear online on January 17 in the journal Nature Communications.

    “Earthquakes originate along fault lines deep underground where extreme conditions can cause chemical reactions and phase transitions that affect the friction between rocks as they move against one another,” said Hadrien Rattez, a research scientist in civil and environmental engineering at Duke. “Our model is the first that can accurately reproduce how the amount of friction decreases as the speed of the rock slippage increases and all of these mechanical phenomena are unleashed.”

    For three decades, researchers have built machines to simulate the conditions of a fault by pushing and twisting two discs of rock against one another. These experiments can reach pressures of up to 1450 pounds per square inch and speeds of one meter per second, which is the fastest underground rocks can travel. For a geological reference point, the Pacific tectonic plate moves at about 0.00000000073 meters per second.

    3
    Pacific Plate. USGS

    4
    The tectonic plates of the world were mapped in 1996, USGS.

    “In terms of ground movement, these speeds of one meter per second are incredibly fast,” said Manolis Veveakis, assistant professor of civil and environmental engineering at Duke. “And remember that friction is synonymous with resistance. So if the resistance drops to zero, the object will move abruptly. This is an earthquake.”

    In these experiments, the surface of the rocks either begins to turn into a sort of gel or to melt, lowering the coefficient of friction between them and making their movement easier. It’s been well established that as the speed of these rocks relative to one another increases to one meter per second, the friction between them drops like a rock, you might say, no matter the type. But until now, nobody had created a model that could accurately reproduce these behaviors.

    In the paper, Rattez and Veveakis describe a computational model that takes into account the energy balance of all the complicated mechanical processes taking place during fault movement. They incorporate weakening mechanisms caused by heat that are common to all types of rock, such as mineral decomposition, nanoparticle lubrication and melting as the rock undergoes a phase change.

    5
    Researchers twist rock discs against one another under large amounts of pressure at high speeds to simulate what happens during earthquakes at fault lines. New models from Duke engineers are the first that can accurately reproduce how the amount of friction decreases as the speed of the rock slippage increases and the rock undergoes a phase change. Credit – Giulio DiToro (University of Padova), Elena Spagnuolo and Stefano Aretusini (National Institute of Geophysics and Volcanology, Rome).

    After running all of their simulations, the researchers found that their new model accurately predicts the drop in friction associated with the entire range of fault speeds from experiments on all available rock types including halite, silicate and quartz.

    Because the model works well for so many different types of rock, it appears to be a general model that can be applied to most situations, which can reveal new information about the origins of earthquakes. While researchers can’t fully recreate the conditions of a fault, models such as this can help them extrapolate to higher pressures and temperatures to get a better understanding of what is happening as a fault builds toward an earthquake.

    “The model can give physical meaning to observations that we usually cannot understand,” Rattez said. “It provides a lot of information about the physical mechanisms involved, like the energy required for different phase transitions.”

    “We still cannot predict earthquakes, but such studies are necessary steps we need to take in order to get there,” said Veveakis. “And in theory, if we could interfere with a fault, we could track its composition and intervene before it becomes unstable. That’s what we do with landslides. But, of course, fault lines are 20 miles underground, and we currently don’t have the drilling capacity to go there.”

    This work was supported by the Southern California Earthquake Center (118062196) under the National Science Foundation (EAR-1033462) and the United States Geological Survey (G12AC20038).

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Younger than most other prestigious U.S. research universities, Duke University consistently ranks among the very best. Duke’s graduate and professional schools — in business, divinity, engineering, the environment, law, medicine, nursing and public policy — are among the leaders in their fields. Duke’s home campus is situated on nearly 9,000 acres in Durham, N.C, a city of more than 200,000 people. Duke also is active internationally through the Duke-NUS Graduate Medical School in Singapore, Duke Kunshan University in China and numerous research and education programs across the globe. More than 75 percent of Duke students pursue service-learning opportunities in Durham and around the world through DukeEngage and other programs that advance the university’s mission of “knowledge in service to society.”

     
  • richardmitnick 12:25 pm on May 2, 2019 Permalink | Reply
    Tags: Duke University,   

    From Duke University: “Women in STEM at Duke” 

    Duke Bloc
    Duke Crest

    From Duke University

    April 22, 2019
    Stephen Schramm

    1
    James B. Duke Professor of Mathematics and Electrical and Computer Engineering Ingrid Daubechies is one of Duke University’s most accomplished faculty members. Photo by Justin Cook.

    Jennifer West’s lab takes up an entire corner of Gross Hall’s third floor. Among the things West and her team are investigating in the lab is the use of nanoparticles that, when introduced into the body and exposed to infrared light, can heat up and destroy tumors. Duke has been West’s home since 2012. With its enthusiastic support of her research, it will likely remain so for a long time. But, at other points in her career, West hasn’t felt as comfortable.

    At her first-year student orientation at the Massachusetts Institute of Technology, she was one of few women in an auditorium filled with men. There were times in graduate school and as a faculty member elsewhere when she was her department’s only woman. “There was a palpable sense that we were the minority,” said West, the Fitzpatrick Family University Professor of Engineering at Duke.

    For women who work, teach and study in science, technology, engineering and mathematics – often referred to as STEM fields – this is a familiar scenario. In both education and employment, women are often underrepresented in these disciplines.

    2
    Jennifer West, third from left, stands with students in her lab. Photo courtesy of Pratt School of Engineering.

    A report on the issue, “Solving the Equation,” by the American Association of University Women, states that “diversity in the workforce contributes to creativity, productivity and innovation. The United States can’t afford to ignore the perspectives of half the population in future engineering and technical designs.”

    At Duke, leaders, students, faculty and staff recognize the need to create inclusive environments in STEM fields. In its current academic strategic plan, Duke makes bolstering research and education in STEM fields a top priority and calls for more women to be involved in leading that charge.

    “We’re trying to shine a light on science and technology in general,” said Duke Provost Sally Kornbluth, a cell biologist. “But within that effort is a focus on diversifying our workforce and faculty cohort.”

    Working for Change

    3
    Rochelle Newton has four decades of experience working in information technology. Photo by Justin Cook.

    Rochelle Newton was a teenager in the 1970s when she began working with computers, feeding trays of punch cards into hulking contraptions that produced a fraction of the computing power of today’s smartphones.

    During her time in information technology, Newton, now senior systems and user services manager for the Duke University School of Law, has seen a head-spinning amount of technological change.

    The rate of change for women in the field, however, has been slower.

    The Bureau of Labor Statistics reports that, while women make up 46.9 percent of the nation’s labor force, they hold 25.5 percent of jobs in computer and mathematical occupations, up slightly from 24.8 percent a decade ago. At Duke, women hold 32.5 percent of positions in information technology, down from 33.5 percent a decade ago.

    Duke’s Office of Information Technology is trying to expand the range of voices in technology with intern programs that draw students from underrepresented populations, and through “Diversify IT,” a program providing networking and educational opportunities for IT professionals from all backgrounds.

    “If women represent half the population, they’re also half of the people using technology,” said Tracy Futhey, Duke’s vice president and chief information officer. “If the technologies they’re using are overwhelmingly designed by men, without involvement from women, they’re likely not going to be as welcoming, usable or interesting as technologies designed with a broader set of perspectives at the table.”

    Stories like Newton’s illustrate gradual progress in the field.

    Newton was the only woman or person of color at her first job decades ago in Virginia, where she said co-workers played mean-spirited pranks.

    “It was really hard, but I was stubborn,” Newton said. “I was going to persevere no matter what.”

    As technology advanced, so did Newton’s career. After earning multiple degrees, Newton joined Duke’s staff in 2008. Here, Newton completed professional development programs, such as the Duke Leadership Academy, and became an in-demand speaker on diversity in tech, all while earning a doctorate in higher education administration.

    Now, she’s creating the community she lacked earlier in her career with an informal group called “Techs and Collaborators.” The diverse collection of Duke IT professionals meets monthly, discussing upcoming projects and other topics. The group’s guiding principle is inclusiveness.

    “I don’t care what color you are, what gender you are, come to the table and bring what you can,” Newton said.

    Showing the Way

    3
    Early in her career in mathematics, Ingrid Daubechies drew inspiration from the women who charted the same path before her. Photo by Justin Cook.

    Ingrid Daubechies grew up in Belgium where public education was segregated by gender. It wasn’t until she studied physics in college that she ran into anyone questioning a woman’s place in science.

    “I knew I was good at it,” said Daubechies, the James B. Duke Professor of Mathematics and Electrical and Computer Engineering. “I didn’t see it as an indictment of me, but of them.”

    Still, as she began a career in academia, even she experienced self-doubt.

    Daubechies worried her outgoing demeanor might be out of place among faculty. But once she met Irina Veretennicoff, a successful Belgian quantum mechanics professor who had a warm, gregarious personality, Daubechies’ concerns were silenced.

    Likewise, when Daubechies wondered if motherhood would conflict with her career, her fears were eased when she met acclaimed mathematician and mother of four Cathleen Morawetz.

    “As soon as I met one example, it was enough to show me it’s possible,” Daubechies said.

    Women who have successfully navigated STEM careers often carry the aspirations of those who hope to follow. That’s why developing strong female role models among the STEM faculty is a Duke priority.

    In “Together Duke,” the Academic Strategic Plan released in 2017, the university said it would “aggressively recruit and support women and underrepresented minorities in STEM fields.”

    Provost Sally Kornbluth said a key part of the initiative is bringing in elite female faculty members – like Daubechies, who came to Duke from Princeton in 2011 – to inspire students. Research has shown that women with female professors perform better in introductory STEM classes and are more likely to earn STEM degrees than those with male professors.

    So the presence of accomplished scientists such as Trinity College of Arts & Sciences Dean Valerie Ashby, a chemist, and department chairs such as chemistry’s Katherine Franz, evolutionary anthropology’s Susan Alberts and statistical science’s Merlise Clyde, looms large.

    “I would like women students to see many successful women role models so they can picture themselves being successful scientists one day,” Kornbluth said.

    Paying it Forward

    5
    Duke students from FEMMES (Females Excelling More in Math, Engineering and Science) help middle school students with science experiments. Photo by Justin Cook.

    On a recent Saturday, laughter spilled from some classrooms in the otherwise empty Physics Building on campus. Middle-school-aged girls and Duke undergraduates clustered around tables, creating exothermic and endothermic reactions with water, baking soda and calcium chloride.

    For Duke sophomore Megan Phibbons, part of FEMMES – Females Excelling More in Math Engineering and Science, the student-run organization that hosted the event – hearing the girls’ happy voices was a thrill.

    “It’s really easy to get talked over when you’re a young girl,” said Phibbons, a FEMMES executive board member. “Here, nobody gets talked over. It’s a supportive environment.”

    While Duke staff and faculty are tackling the issue of female underrepresentation in STEM fields, Duke’s students are, too.

    FEMMES is one of several student groups aimed at broadening the network of science-minded women both at Duke and beyond. That’s important because, according to the National Center for Education Statistics, women received 57.2 percent of all bachelor’s degrees during the 2016-17 academic year but 35.7 percent of those degrees are in STEM fields.

    Founded at Duke in 2006, FEMMES engages girls with STEM fields through fun and functional activities led by college students. The program has expanded to other universities and now organizes after school, weekend and summer programs.

    “It sets an example of ‘I can do this, too,’” Duke senior and FEMMES Co-President Carolyn Im said. “It shows that there are women pursuing these things, and if you want to do it, you can.”

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Duke Campus

    Younger than most other prestigious U.S. research universities, Duke University consistently ranks among the very best. Duke’s graduate and professional schools — in business, divinity, engineering, the environment, law, medicine, nursing and public policy — are among the leaders in their fields. Duke’s home campus is situated on nearly 9,000 acres in Durham, N.C, a city of more than 200,000 people. Duke also is active internationally through the Duke-NUS Graduate Medical School in Singapore, Duke Kunshan University in China and numerous research and education programs across the globe. More than 75 percent of Duke students pursue service-learning opportunities in Durham and around the world through DukeEngage and other programs that advance the university’s mission of “knowledge in service to society.”

     
  • richardmitnick 10:29 am on September 7, 2018 Permalink | Reply
    Tags: AIM-Adaptable Interpretable Machine Learning, , Black-box models, Duke University, , ,   

    From MIT News: “Taking machine thinking out of the black box” 

    MIT News
    MIT Widget

    From MIT News

    September 5, 2018
    Anne McGovern | Lincoln Laboratory

    1
    Members of a team developing Adaptable Interpretable Machine Learning at Lincoln Laboratory are: (l-r) Melva James, Stephanie Carnell, Jonathan Su, and Neela Kaushik. Photo: Glen Cooper.

    Adaptable Interpretable Machine Learning project is redesigning machine learning models so humans can understand what computers are thinking.

    Software applications provide people with many kinds of automated decisions, such as identifying what an individual’s credit risk is, informing a recruiter of which job candidate to hire, or determining whether someone is a threat to the public. In recent years, news headlines have warned of a future in which machines operate in the background of society, deciding the course of human lives while using untrustworthy logic.

    Part of this fear is derived from the obscure way in which many machine learning models operate. Known as black-box models, they are defined as systems in which the journey from input to output is next to impossible for even their developers to comprehend.

    “As machine learning becomes ubiquitous and is used for applications with more serious consequences, there’s a need for people to understand how it’s making predictions so they’ll trust it when it’s doing more than serving up an advertisement,” says Jonathan Su, a member of the technical staff in MIT Lincoln Laboratory’s Informatics and Decision Support Group.

    Currently, researchers either use post hoc techniques or an interpretable model such as a decision tree to explain how a black-box model reaches its conclusion. With post hoc techniques, researchers observe an algorithm’s inputs and outputs and then try to construct an approximate explanation for what happened inside the black box. The issue with this method is that researchers can only guess at the inner workings, and the explanations can often be wrong. Decision trees, which map choices and their potential consequences in a tree-like construction, work nicely for categorical data whose features are meaningful, but these trees are not interpretable in important domains, such as computer vision and other complex data problems.

    Su leads a team at the laboratory that is collaborating with Professor Cynthia Rudin at Duke University, along with Duke students Chaofan Chen, Oscar Li, and Alina Barnett, to research methods for replacing black-box models with prediction methods that are more transparent. Their project, called Adaptable Interpretable Machine Learning (AIM), focuses on two approaches: interpretable neural networks as well as adaptable and interpretable Bayesian rule lists (BRLs).

    A neural network is a computing system composed of many interconnected processing elements. These networks are typically used for image analysis and object recognition. For instance, an algorithm can be taught to recognize whether a photograph includes a dog by first being shown photos of dogs. Researchers say the problem with these neural networks is that their functions are nonlinear and recursive, as well as complicated and confusing to humans, and the end result is that it is difficult to pinpoint what exactly the network has defined as “dogness” within the photos and what led it to that conclusion.

    To address this problem, the team is developing what it calls “prototype neural networks.” These are different from traditional neural networks in that they naturally encode explanations for each of their predictions by creating prototypes, which are particularly representative parts of an input image. These networks make their predictions based on the similarity of parts of the input image to each prototype.

    As an example, if a network is tasked with identifying whether an image is a dog, cat, or horse, it would compare parts of the image to prototypes of important parts of each animal and use this information to make a prediction. A paper on this work: “This looks like that: deep learning for interpretable image recognition,” was recently featured in an episode of the “Data Science at Home” podcast. A previous paper, “Deep Learning for Case-Based Reasoning through Prototypes: A Neural Network that Explains Its Predictions,” used entire images as prototypes, rather than parts.

    The other area the research team is investigating is BRLs, which are less-complicated, one-sided decision trees that are suitable for tabular data and often as accurate as other models. BRLs are made of a sequence of conditional statements that naturally form an interpretable model. For example, if blood pressure is high, then risk of heart disease is high. Su and colleagues are using properties of BRLs to enable users to indicate which features are important for a prediction. They are also developing interactive BRLs, which can be adapted immediately when new data arrive rather than recalibrated from scratch on an ever-growing dataset.

    Stephanie Carnell, a graduate student from the University of Florida and a summer intern in the Informatics and Decision Support Group, is applying the interactive BRLs from the AIM program to a project to help medical students become better at interviewing and diagnosing patients. Currently, medical students practice these skills by interviewing virtual patients and receiving a score on how much important diagnostic information they were able to uncover. But the score does not include an explanation of what, precisely, in the interview the students did to achieve their score. The AIM project hopes to change this.

    “I can imagine that most medical students are pretty frustrated to receive a prediction regarding success without some concrete reason why,” Carnell says. “The rule lists generated by AIM should be an ideal method for giving the students data-driven, understandable feedback.”

    The AIM program is part of ongoing research at the laboratory in human-systems engineering — or the practice of designing systems that are more compatible with how people think and function, such as understandable, rather than obscure, algorithms.

    “The laboratory has the opportunity to be a global leader in bringing humans and technology together,” says Hayley Reynolds, assistant leader of the Informatics and Decision Support Group. “We’re on the cusp of huge advancements.”

    Melva James is another technical staff member in the Informatics and Decision Support Group involved in the AIM project. “We at the laboratory have developed Python implementations of both BRL and interactive BRLs,” she says. “[We] are concurrently testing the output of the BRL and interactive BRL implementations on different operating systems and hardware platforms to establish portability and reproducibility. We are also identifying additional practical applications of these algorithms.”

    Su explains: “We’re hoping to build a new strategic capability for the laboratory — machine learning algorithms that people trust because they understand them.”

    See the full article here .


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    Please help promote STEM in your local schools.


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    The mission of MIT is to advance knowledge and educate students in science, technology, and other areas of scholarship that will best serve the nation and the world in the twenty-first century. We seek to develop in each member of the MIT community the ability and passion to work wisely, creatively, and effectively for the betterment of humankind.

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  • richardmitnick 11:01 am on September 5, 2018 Permalink | Reply
    Tags: Duke University, , , , ,   

    From Duke University via The News&Observer: “Look out, IBM. A Duke-led group is also a player in quantum computing” 

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    From Duke University

    via

    The News&Observer

    August 13, 2018
    Ray Gronberg

    1
    Duke University professors Iman Marvian, Jungsang Kim and Kenneth Brown, gathered here in Kim’s lab in the Chesterfield Building in downtown Durham, are working together to develop a quantum computer that relies on “trapped ion” technology. The National Science Foundation and the federal Intelligence Advanced Research Projects Activity are helping fund the project. Les Todd LKT Photography, Inc.

    There’s a group based at Duke University that thinks it can out-do IBM in the quantum-computing game, and it just got another $15 million in funding from the U.S. government.

    Quantum computing – IBM

    The National Science Foundation grant is helping underwrite a consortium led by professors Jungsang Kim and Ken Brown that’s previously received backing from the federal Intelligence Advanced Research Projects Activity.

    Kim said the group is developing a quantum computer that has “up to a couple dozen qubits” of computational power and reckons it’s a year or so from being operational. The world qubit is the quantum-computing world’s equivalent of normal computing’s “bit” when it comes to gauging processing ability, and each additional qubit represents a doubling of that power.

    “One of the goals of this [grant] is to establish the hardware so we can allow researchers to work on the software and systems optimization,” Kim said of the National Science Foundation grant the agency awarded on Aug. 6.

    Two or three dozen qubits might not sound like a lot when IBM says it has built and tested a 50-qubit machine. But the Duke-led research group is approaching the problem from an entirely different angle.

    The “trapped-ion” design it’s using could hold qubits steady in its internal memory for much longer than superconducting designs like those IBM is working on can manage, Brown said.

    Superconducting designs — which operate at extremely cold temperatures — “are a bit faster” than trapped-ion ones and are the focus of “a much larger industrial effort,” Brown said.

    That speed-versus-resilience tradeoff could matter because IBM says its machines can hold a qubit steady in memory for only up to about 90 microseconds. That means processing runs have to be short, on the order of no more than a couple of seconds total.

    “One thing that’s becoming clear in the community is, the thing we need to scale is not just the number of qubits but also the quality of operations,” said Brown, who in January traded a faculty post at Georgia Tech for a new one at Duke. “If you have a huge number of qubits but the operations are not very good, you effectively have a bad classical computer.”

    Kim added that designers working on quantum computers have to look for the same kind of breakthrough in thinking about the technology that the Wright brothers brought to the development of flight.

    Just as the Wrights and other people working in the field in the late 19th and early 20th centuries figured out that mimicking birds was a developmental dead end, the builders of quantum computers “have to start with something that’s fundamentally quantum and build the right technology to scale it,” Kim said. “You don’t build quantum computers by mimicking classical computers.”

    But for now, the government agencies that are subsidizing the field are backing different approaches and waiting to see what pans out.

    The Aug. 6 grant is the third big one Kim’s lab has secured, building on awards from IARPA in 2010 and 2016 that together brought it about $54.5 million in funding. But in both those rounds of funding, teams from IBM were also among those getting awards from the federal agency, which funds what it calls “high-risk/high-payoff” research for the intelligence community.

    The stakes are so high because quantum computing could become a breakthrough technology. It exploits the physics of subatomic particles in hopes of developing a machine that can process data that exists in multiple states at once, rather than the binary 1 or 0 of traditional computing.

    IBM and the government aren’t the only heavy hitters involved. Google has a quantum-computing project of its own that’s grown with help from IARPA funding.

    3
    Google’s Quantum Dream Machine

    Kim and other people involved in the Duke-led group have also formed a company called IonQ that’s received investment from Google and Amazon.

    The Duke-led group also includes teams from from the University of Maryland, the University of Chicago and Tufts University that are working on hardware, software and applications development, respectively, Duke officials say. Researchers from the University of New Mexico, MIT, the National Institute of Standards and Technology and the University of California-Berkeley are also involved.

    Duke doesn’t have quantum computing all to itself in the Triangle, as in the spring IBM made N.C. State University part of its Q Network, a group of businesses, universities and government agencies that can use IBM’s quantum machines via the cloud.

    But the big difference between the N.C. State and Duke efforts is that with State, the focus is on developing both the future workforce and beginning to push software development, while at Duke it’s more fundamentally about trying to develop the technology.

    Not that software is a side issue, mind.

    “If I had a quantum computer with 60 qubits, I know there are algorithms I can run on it that I can’t simulate with my regular computers,” Brown said, explaining that the technology requires new thinking there, too. “That’s a weird place to be.”

    The quantum project is important enough that Duke has backed it with faculty hires. Brown had been collaborating with Kim’s group for a while, but elected to move to Duke from Georgia Tech after Duke officials decided to conduct what Kim termed “a cluster hire” of quantum specialists.

    Brown joined Kim in the Pratt School of Engineering’s electrical and computer engineering department. A search for someone to fill an an endowed chair in physics continues.

    Another professor involved, Iman Marvian, also joined the Duke faculty at the start of 2018 thanks to the university’s previously announced “quantitative initiative.” A quantum information theorist, he got a joint appointment in physics and engineering. He came to Duke from MIT after a post-doc stint at the Boston school.

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    Duke Campus

    Younger than most other prestigious U.S. research universities, Duke University consistently ranks among the very best. Duke’s graduate and professional schools — in business, divinity, engineering, the environment, law, medicine, nursing and public policy — are among the leaders in their fields. Duke’s home campus is situated on nearly 9,000 acres in Durham, N.C, a city of more than 200,000 people. Duke also is active internationally through the Duke-NUS Graduate Medical School in Singapore, Duke Kunshan University in China and numerous research and education programs across the globe. More than 75 percent of Duke students pursue service-learning opportunities in Durham and around the world through DukeEngage and other programs that advance the university’s mission of “knowledge in service to society.”

     
  • richardmitnick 8:24 am on March 21, 2018 Permalink | Reply
    Tags: Autonomously mapping the ocean floor, Blue Devil Ocean Engineering team, Duke Students Advance to Finals in $7 Million Ocean Discovery XPRIZE Competition, Duke University, Ocean Health XPRIZE, , Pratt School of Engineering   

    From Duke: “Duke Students Advance to Finals in $7 Million Ocean Discovery XPRIZE Competition” 

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    Duke University

    1

    March 7, 2018
    Ken Kingery

    After years of work from hundreds of students, the Duke Ocean XPRIZE team has qualified for the final round of competition aimed at autonomously mapping the ocean floor.

    2
    Duke Engineering students stand with their prototype heavy-lifting drone after a test flight for the Ocean Discovery XPRIZE competition. No image credit.

    Building on the research of more than two years of students in an innovative engineering course, a Duke University team is among the final nine teams left standing in the $7 million Shell Ocean Discovery XPRIZE that will conclude this fall.

    The Shell Ocean Discovery XPRIZE presents teams with the ambitious goal of mapping 250 square kilometers of ocean up to 4,000 meters deep within a half-meter resolution in less than 24 hours. The competition also requires teams to identify and image 10 archeological, biological or geological features. To make the task even harder, no boats or humans are allowed—the surveying must be completed with a system of autonomous drones that can all fit within a standard shipping container.

    “A lot of people who do this sort of work for a living didn’t even bother trying to compete,” said Martin Brooke, associate professor of electrical and computer engineering at Duke and leader of Duke’s team. “Most people viewed this challenge as completely and totally impossible. And they might be right.”

    The XPRIZE contests have a reputation for being challenging and audacious. The Google Lunar XPRIZE competition to send a robot to the moon ended this year without a winner. But the original Ansari XPRIZE to launch people into space with a reusable spacecraft found a winner, and the Wendy Schmidt Ocean Health XPRIZE aimed at developing ocean pH sensors found three.

    Whether teams are able to complete the challenge or not, the lofty goals of the XPRIZE competitions serve to push science forward, catalyze new markets and provide incentives for talented, intelligent people to innovate and make significant impacts.

    More than 30 teams submitted proposals at the start of the competition, and 19 were chosen as semi-finalists based on their technical merits in early 2017. These teams included more than 350 people from 25 countries, ranging from undergraduate students to industry professionals. The Duke team is joined in the finals by just one other university-based team, from Texas A&M. Both student teams will be competing against teams formed by industry professionals in Germany, Switzerland, Japan, Portugal, England and the United States.

    The Blue Devil Ocean Engineering team has taken an unusual tactic—several undergraduate classes were formed at the start of the competition to begin work on the project. While a handful of graduate students and undergraduate students working through independent studies have been able to stick with the project since its inception, most of the work being done each year is by an entirely new set of students. This means that few of the students finishing the competition this fall will have been the ones who started it in 2016.

    “Each year there’s a bit of a slowdown as the new students come up to speed on the project. But at the same time, they come in with fresh ideas and a lot of energy,” said Doug Nowacek, the Randolph K. Repass and Sally-Christine Rodgers University Associate Professor of Conservation Technology in Duke’s Nicholas School of the Environment and Pratt School of Engineering.

    3
    A computer-generated rendering of the initial prototype for the heavy-lifting drone designed to compete in the Ocean Discovery XPRIZE.

    Duke’s approach is to use giant heavy-lifting drones to deploy and retrieve a series of sonar-equipped sensors that are lowered from floating platforms at the ocean’s surface. This is much more difficult than it sounds.

    The drones must autonomously navigate gusting winds and waves that average six meters in height while dropping off and retrieving the sensors. The floating sensor platforms must carry at least 3,500 meters of cable to lower and then pull up the sensor pods, making them extremely heavy for the drones to carry. The sensor pods themselves must withstand the pressure, temperature and salinity of the ocean’s depths. And to successfully map the area required, the team must deploy multiple drones making multiple drop-offs and pick-ups, and then seamlessly analyze all of the data.

    To advance to the final round, the semifinalist teams had to pass a Round 1 Technology Readiness Test, which comprised site visits to each team by XPRIZE staff and judges. The teams were tested against 11 measurement criteria to show their technological solutions were capable of meeting the operational requirements necessary for rapid, unmanned and high-resolution ocean mapping and discovery.

    When the judges visited Duke, they saw a team with all of its components in place. The team has built and flown a heavy-lift drone in Duke Forest. They have sensor pods that have been tested at the Duke University Marine Laboratory in Beaufort, North Carolina. They have software to analyze the resulting data. The combination was enough to move them into the final round of competition.

    As the school year draws to a close, more than 50 students are now working to finalize their design. More rotors are being added to the drone to make sure it can lift the heavy sensor pods. Control software is being smoothed so that the drone can pick up the pods while using as little energy as possible. And the sensor pods themselves are receiving upgrades to increase their range so that fewer drops are needed to cover the area required in the final stage of competition.

    4
    Students test a prototype floating launching pad for their sonar pods. No image credit.

    “Our goal is to get this project to the point where all the next group of students need to do is build more of the drones and sensors that we’ve already completed,” said William Willis, a junior studying mechanical engineering who plans to continue participating during his senior year.

    “We want to demonstrate a full cycle of dropping off a sensor, mapping an area and picking it up before graduation in May,” added Nick Lockett, a senior studying electrical engineering.

    The team hopes to get some help assembling more units over the summer from high school students brought in by Tyler Bletsch, assistant professor of the practice of electrical and computer engineering at Duke, who has also been instrumental to the project. Whether or not they are successful in either their short-term goals or the final competition, the massive, long-term project has been valuable for everyone involved.

    “This project has given us a chance to work on electrical engineering problems in a real-world setting,” said Krista Opsahl-Ong, also a senior studying electrical engineering. “And I don’t mean just from a science perspective. We’ve had to work with a huge team with a lot of moving parts. It’s forced us to segment our work and keep track of a lot of parallel projects. And of course it’s been a ton of fun to actually get our hands dirty.”

    The nine finalist teams will be formally recognized and awarded at Oceanology International’s Catch the Next Wave conference in London on March 15. Attending the event for the Duke University team will be Brooke and graduating senior Sam Kelly—one of the few undergraduate students who has worked on the project since its inception. The final Round 2 testing will take place during October and November of 2018.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

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    Duke Campus

    Younger than most other prestigious U.S. research universities, Duke University consistently ranks among the very best. Duke’s graduate and professional schools — in business, divinity, engineering, the environment, law, medicine, nursing and public policy — are among the leaders in their fields. Duke’s home campus is situated on nearly 9,000 acres in Durham, N.C, a city of more than 200,000 people. Duke also is active internationally through the Duke-NUS Graduate Medical School in Singapore, Duke Kunshan University in China and numerous research and education programs across the globe. More than 75 percent of Duke students pursue service-learning opportunities in Durham and around the world through DukeEngage and other programs that advance the university’s mission of “knowledge in service to society.”

     
  • richardmitnick 11:05 am on July 12, 2017 Permalink | Reply
    Tags: An Out of Body Experience, , Duke University, , , The Ice Age May Be Over   

    From Duke: “An Out of Body Experience” 

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    Duke University

    Jul 11, 2017
    Scott Behm

    Each day, tens of thousands of patients on waiting lists across the United States await a simple phone call: one that says a match has been found and an organ is available for transplant. Despite a growing demand for donors, organ shortages continue to hinder many patients’ chances in receiving their potentially life-saving call.

    The organ shortage has impacted several transplant teams at Duke. Carmelo Milano, MD, Professor, Division of Cardiovascular and Thoracic Surgery, says part of the reason for the shortage is the method used to preserve organs while in transit from donor to recipient.

    “Duke has performed over 1,000 heart transplants using cold static storage,” says Dr. Milano, Heart Transplant Surgical Director. (That’s a fancy term for a bag of ice.) “With this method, the heart is removed from the donor and cooled with a solution before it is transported, but lack of oxygen to the organ can cause graft failure.”

    Cold storage has been a staple of the transplant procedure for over 50 years. While this method is serviceable, it is far from ideal. Vital organs are sensitive to cold ischemia while stored on ice, as irreparable damage from a lack of oxygenated blood flow rapidly occurs. When a heart stops beating, or lungs stop breathing, the organ slowly dies.

    Cold storage slows down the deterioration process but not entirely, and this race against the clock severely limits organ availability. The heart is particularly sensitive to cold ischemia. Consequently, Duke’s range of potential donors for heart transplants has been limited to those east of the Mississippi, according to Dr. Milano.

    The lung transplant team faces similar obstacles, says Matthew Hartwig, MD, Associate Professor, Division of Cardiovascular and Thoracic Surgery. Though the team has successfully transplanted lungs held in cold storage for longer than the conservative 4-hour window, Dr. Hartwig says doing so can create more complications. With such a small window of time, organ matches found a considerable distance away often go unused.

    1
    Transplant surgeon Matthew Hartwig examines a set of donor lungs,
    transported to Duke in the time-honored bag of ice. (Photo: Shawn Rocco)

    The most logical answer to the cold storage problem is also the most challenging: keep a transplanted organ in a near-physiologic state while outside of the body, perfused with blood, and limit the amount of time the organ is kept on ice.

    Though the ability to keep an organ alive outside of the body may sound like something out of science fiction, perfusion systems make this a reality. The devices keep an organ as functional as possible after surgical removal, during a process known as “ex vivo perfusion.” Rather than using ice, the device stores the organ at close to body temperature, causing less injury. Nutrient-rich blood taken from the donor filters through the organ, and the system allows close monitoring while the donated organ remains in a living state: beating, breathing, or producing bile, metabolizing glucose and balancing the blood’s chemistry.

    Several Duke teams are at the forefront of national clinical studies to examine the effectiveness of these devices in transplant procedures.

    Duke’s cardiac transplant team has partnered with TransMedics, whose portable Organ Care System™ (OCS) allows the heart to be perfused while in transit from donor to recipient. Dubbed the “heart in a box,” the device is sent with the procurement team to retrieve the heart, which is transported back to the transplant center.

    The first successful surgery at Duke using an organ transported via the OCS was performed in July 2016. The surgery would not have been possible without the new system due to the distance the organ had to travel, says Dr. Milano. Since then, surgeons have performed eight more successful transplants using the OCS.

    The lung transplant team has also had success using a device developed by XVIVO Perfusion, completing 25 successful transplants and enrolling more patients than any other center in the United States for the trial. Lungs are fragile organs at high risk for infection due to their role as a main filter of our outside environment. This fragility comes at a cost: the Organ Procurement and Transplantation Network reports only 1 in 4 donated lungs is viable for transplant.

    Duke’s trial with the XVIVO system focused specifically on lungs that initially would not have been accepted for transplant. Using a perfusion device allows the lungs to breathe without straining, making the organ stronger and healthier outside of the body.

    The liver transplant team formed a third partnership with OrganOx. The manufacturer’s metra device allows the donor’s liver to be preserved for up to 24 hours prior to transplant. This clinical trial began in February of 2017.

    “There are several benefits to using the device,” explains Andrew Barbas, MD, Assistant Professor, Division of Abdominal Transplant Surgery. “We can access the metabolic activity of the liver and restore energy levels in liver cells. We can also assess which organs will function better after transplant.”

    This evaluation period prior to the transplant procedure can be critical to success, and perfusion devices offer the surgeon more breathing room to examine the organ fully before surgery begins.

    Expanding the Donor Pool

    Duke’s transplant surgeons all say perfusion systems can increase the number of organs available. Longer preservation times allow organs to travel greater distances, offering a larger geographic area to search for matches.

    But more important than geography is the ability to use “extended criteria organs,” says Jacob Schroder, MD, Assistant Professor, Division of Cardiovascular and Thoracic Surgery.

    “Extended criteria hearts have some feature that makes them imperfect—ventricular hypertrophy, minor coronary disease, advanced age of the donor, certain causes of death, or a long estimated ischemic time,” says Dr. Schroder. “The success rate for these hearts has traditionally been very low, but the OCS™ device allows us to take the ischemic time out of the question.”

    Whether heart, lung, or liver, when the threat of damage from cold storage is minimized, more organs become viable options for patients in need. To put it simply, Dr. Schroder explains that utilizing the OCS is the equivalent of transplanting an organ from a donor found in Raleigh, rather than farther away. It entails less risk, and more positive outcomes.

    The Future of Ex Vivo Perfusion

    3
    A Duke liver transplant team poses with the OrganOx system. The donor liver
    is in the clear box at the lower right, sustained by donor blood, saline and a pump.

    Perfusion also raises an interesting question about the ability to rehabilitate organs while outside of the body: Is it possible to transplant an organ in a better condition than when it was procured?

    Dawn Bowles, PhD, Assistant Professor, Division of Surgical Sciences, believes this may be a possibility. She has conducted biological therapy studies using pig hearts perfused in the TransMedics OCS.

    “These devices answer questions about whether or not a heart can be rehabilitated while it is stored,” says Bowles. “It is possible that we could fix some things that need fixing in a heart before it is transplanted.”

    While this type of therapy is still on the horizon, it highlights the potential of the new technology. Through a grant from the American Society of Transplant Surgeons, Dr. Barbas is using animal models to test the possibility of repairing damaged livers through perfusion.

    Repairing organs ex vivo may be another solution to the organ shortage problem.

    This potential application may already be a reality for lung transplants. Duke’s next trial with United Therapeutics will test the use of what Dr. Hartwig calls an “organ hospital” — a centralized location where organs are rehabilitated before transplantation.

    “This technology is still in its infancy, but I can see our program being able to use the devices to not only stabilize lungs while outside of the body, but to intervene and improve them,” says Dr. Hartwig.

    Healthier organs available in greater numbers means more patients could receive the life-saving operations they need. For many patients awaiting a transplant, the wait for their phone call may become shorter.

    See the full article here .

    Please help promote STEM in your local schools.

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    Younger than most other prestigious U.S. research universities, Duke University consistently ranks among the very best. Duke’s graduate and professional schools — in business, divinity, engineering, the environment, law, medicine, nursing and public policy — are among the leaders in their fields. Duke’s home campus is situated on nearly 9,000 acres in Durham, N.C, a city of more than 200,000 people. Duke also is active internationally through the Duke-NUS Graduate Medical School in Singapore, Duke Kunshan University in China and numerous research and education programs across the globe. More than 75 percent of Duke students pursue service-learning opportunities in Durham and around the world through DukeEngage and other programs that advance the university’s mission of “knowledge in service to society.”

     
  • richardmitnick 12:21 pm on June 7, 2017 Permalink | Reply
    Tags: , , Duke University, Research the world with drones   

    From Duke: “Research from a New Point of View” 

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    Duke University

    April 17, 2017 [Where have yo been hiding, Duke?]

    Karl Bates
    Laura Brinn
    Eric Ferreri

    Drone technology provides new opportunities for Duke research—both within the university and out in the field.

    To get some overhead images while doing archaeology field work several years ago, members of Katherine McCusker’s archaeology research team rigged a camera to a weather balloon attached to a really long rope. They let the balloon drift upward, holding tight to the rope while hoping the camera was programmed properly to snap some photos.

    “You hope the wind isn’t too strong and the camera is at the right angle,” McCusker, now a doctoral student at Duke, recalls. “That was our low-tech solution. We got some really nice photos – but they weren’t useful for research.”

    McCusker remembers those makeshift camerawork days often now as she pilots drones over the Italian countryside, watching in real time as it records digital data.

    “…The use of drones is really changing how research is done….”
    — Lawrence Carin, Vice Provost for Research

    McCusker works in Duke’s Dig@Lab, where professor Maurizio Forte leads a team that uses drones and other high-tech resources to efficiently examine Italian landscapes in search of clues to ancient civilizations. In Forte’s lab and across the university – and in higher education more generally – researchers are finding myriad uses for these relatively inexpensive new tools that provide a valuable new vantage point for examination of everything from ancient Roman ruins to the eating habits of whales to the migratory patterns of turtles.

    “Drones are certainly introducing new opportunities for research in some important areas,” said Lawrence Carin, Duke’s Vice Provost for Research. “Especially in the environmental sector, the use of drones is really changing how research is done.”

    At Duke, researchers from across the academic spectrum are finding uses for drones and other high-tech tools that speed their work.

    McCusker has spent the last three summers in Vulci, an Etruscan archaeological site in the Viterbo province in Italy.

    2
    Vulci. http://www.etruriaoggi.it/il-parco-di-vulci-come-non-lo-avete-mai-visto/

    With images recorded by drones, she’s able to examine the development of civilizations – first the Etruscans, and later the Romans – over a period of roughly seven centuries. Vulci is a treasure trove of history, and drones have helped McCusker and others with the Duke lab narrow their searches, create 3D models that suggest how communities looked way back then. With drone images as a key tool, the team discovered hundreds of new archaeological sites and tombs as well as a Roman forum, and was able to create a virtual model of the archaeological landscape.

    “Drones and other tools have completely changed the speed and quality of research,” said Forte, a professor of both classics and art, art history and visual studies at Duke who has worked in Vulci since 2014. “It has had such a deep impact in so short a time. The research template is different now.”

    Carin, the research vice provost, said he’s seeing a steady increase in the number of faculty expressing interest in using drones in their own research – drawn by the relatively low cost and promise of a literal new view of their scholarly landscape.

    There have been hurdles. Drones are still a new enough that regulators have scrambled to keep up with them. But there are now federal policies in place that Duke and other research universities follow. And Duke has developed its own drone use guidelines for researchers to follow, Carin said.

    3
    4
    Ahmedabad, India. No image credits

    On the outskirts of Ahmedabad, India, a drone helped Duke students and researchers sample trash-burning emissions from a municipal dump site that stood several stories tall. In a setting where it wouldn’t be safe for researchers to climb up high enough to collect the samples, the drone allowed the team to safely and efficiently measure a common source of air pollution over a large spatial area.

    The team attached a small sensor—designed at Professor Mike Bergin’s lab at Duke—to its drone, turning it into a flying air quality monitoring station. Although some research applications require specialized drones, in this case the team used a recreational drone, given that it was easy to use and fly, and stable enough to manage the additional weight of the sensor while in flight.

    Video taken by the drone also improves the researchers’ ability to understand fluctuations in the data.

    “If we see a sudden spike or change in the emissions while we’re analyzing the data, we can check the corresponding point on the video to look for an explanation, such as a passing vehicle or somebody smoking a cigarette,” explained graduate student Heidi Vreeland. “When we look only at the sensor data, we can’t know what source caused the fluctuations—but drones allow us to find out.”

    Bergin, Vreeland and their team acknowledge the limitations of using drones. Drones might not be universally applicable to the type of work they do, due to the risk of potentially interfering with the research process.

    “Drones do attract a lot of attention,” said Vreeland. “We try to be careful that bringing in something like a drone doesn’t inadvertently cause people to change their behavior because they assume the drone is watching or measuring their activity.”

    5
    Weddell Sea. https://cherihunston.wordpress.com/2011/12/02/

    In the Weddell Sea along the coast of Antarctica, drones allow researchers to collect valuable data in the most inhospitable conditions.

    The sea and its shores are notoriously difficult environments to study, but a relatively unobtrusive drone that looks like nothing more than an odd-sounding seabird gives marine scientists some remarkable new abilities.

    With it, scholars with the Duke Marine Lab can accurately count marine turtles as they lay eggs on a Costa Rican beach; differentiate juvenile seals and penguins from their parents using a heat-sensitive camera; map and measure barrier islands before and after storms to see how much sand is moved; and monitor how humpback whales feed on krill in Antarctica’s Weddell Sea.

    And a drone will go where no human would ever want to – through a shower of airborne whale snot to capture precious DNA.

    “We can collect huge volumes of data from even the most remote or extreme locations,” said David Johnston, executive director of the new facility and assistant professor of the practice of marine conservation ecology at Duke’s Nicholas School of the Environment. “ are transforming how we study and learn about the marine environment.”

    Duke’s is the first marine lab to win FAA certification to operate scientific drones and provide training. And these drones aren’t just those octo-copters you can buy at your local big-box store. They also have fixed wing airplanes that can stay aloft for 45 minutes, beaming VR video back to the operator’s headset.

    Their biggest drone is an amphibious plane with a 9-foot wingspan that can fly for 90 minutes at a time. Like several of their other drones, this one can fly itself back and forth within a pre-defined area, like “mowing the lawn” for data.

    The Duke drone workshop, just steps from the water in a former boathouse at the Beaufort, NC lab, is strewn with wings, wires and tiny propellers in various states of disassembly. The program manager, AKA jack of all trades, is retired Col. Everette Newton, who flew F-15s in the Air Force. Newton also trained the Duke archaeologists now using drones in Italy.

    The training covers flight planning, flying drones, data management and analysis and provides a working knowledge of federal and state airspace restrictions and rules. It is intended to prepare more scientists for FAA certification and some participants also get the chance to build and fly their own unmanned craft.

    And what teacher and student each learn is that this new flying technology is a pretty good research aid.

    “As much as it hurts me as a pilot, the drone flies a lot more accurately than me,” Newton told Duke Magazine.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition
    Duke Campus

    Younger than most other prestigious U.S. research universities, Duke University consistently ranks among the very best. Duke’s graduate and professional schools — in business, divinity, engineering, the environment, law, medicine, nursing and public policy — are among the leaders in their fields. Duke’s home campus is situated on nearly 9,000 acres in Durham, N.C, a city of more than 200,000 people. Duke also is active internationally through the Duke-NUS Graduate Medical School in Singapore, Duke Kunshan University in China and numerous research and education programs across the globe. More than 75 percent of Duke students pursue service-learning opportunities in Durham and around the world through DukeEngage and other programs that advance the university’s mission of “knowledge in service to society.”

     
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