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  • richardmitnick 12:42 pm on July 20, 2017 Permalink | Reply
    Tags: , Commercialization of enhanced geothermal systems (EGS), LBNL,   

    From LBNL: “Berkeley Lab to Lead Multimillion-Dollar Geothermal Energy Project” 

    Berkeley Logo

    Berkeley Lab

    July 20, 2017
    Julie Chao
    JHChao@lbl.gov
    (510) 486-6491

    1
    Berkeley Lab scientist Tim Kneafsey demonstrates how he places rock samples, from the Brady Geothermal Field in Nevada, into a stress permeability apparatus, which tests how long a fracture can remain open. (Credit: Marilyn Chung/Berkeley Lab.)

    The Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) will lead a new $9 million project aimed at removing technical barriers to commercialization of enhanced geothermal systems (EGS), a clean energy technology with the potential to power 100 million American homes.

    Berkeley Lab will partner with seven other DOE national labs and six universities to develop field experiments focused on understanding and modeling rock fractures, an essential element of geothermal systems. Scientists will use the Sanford Underground Research Facility (SURF) in South Dakota to create small-scale fracture networks in crystalline rock 1,500 meters below ground.

    “We will be putting instrumentation within tens of meters of the fractures and will be able to detect fracturing at a higher resolution than what has ever been done before,” said Berkeley Lab’s Tim Kneafsey, who leads the project. “The goal is to work towards increasing our understanding of fracturing and fluid flow in EGS, which could provide a significant amount of electricity as a large quantity of accessible hot rock lies untapped across the U.S.”

    In geothermal systems, heat acquired from water circulating in rock fractures deep in the Earth’s crust is extracted for conversion to electricity. Conventional geothermal technology is possible only in locations with particular geological characteristics, either near active volcanic centers or in places with a very high temperature gradient, such as much of Nevada and parts of the western United States. These locations have the three components essential to extracting geothermal energy—heat, fluid, and permeability, a measure of how easily fluid can circulate through the rock’s fractures, picking up heat as it moves.

    With EGS, a fracture network can be enhanced or engineered, thus bypassing the geographic limitations of conventional geothermal energy. EGS could eventually provide more than 100 gigawatts (GW) of economically viable electric generating capacity in the continental United States, a huge increase over the current geothermal capacity of 3.5 GW.

    “Although geothermal energy production is already used effectively, there is a lot we need to learn about how to create and develop an EGS reservoir,” Kneafsey said. “This project will seek to understand the relationship between permeability creation and heat extraction in crystalline rocks under certain stress and temperature conditions.”

    Dubbed EGS Collab, the project has been awarded $9 million for the first year by DOE’s Geothermal Technologies Office. Other national labs partnering in the project include Sandia, Lawrence Livermore, Idaho, Los Alamos, Pacific Northwest, Oak Ridge, and the National Renewable Energy Laboratory.

    Douglas Blankenship, manager of geothermal research at Sandia National Laboratories, is the co-lead with Kneafsey. Additionally, professors from Stanford University, the University of Wisconsin, the South Dakota School of Mines and Technology, the Colorado School of Mines, Penn State University, and the University of Oklahoma will also contribute.

    See the full article here .

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  • richardmitnick 12:58 pm on July 19, 2017 Permalink | Reply
    Tags: , LBNL, New Droplet-on-Tape Method Assists Biochemical Research at X-Ray Lasers, , ,   

    From SLAC: “New Droplet-on-Tape Method Assists Biochemical Research at X-Ray Lasers” 


    SLAC Lab

    February 27, 2017 [Never saw this one before]

    1
    Acoustic droplet ejection allows scientists to deposit nanoliters of sample directly into the X-ray beam, considerably increasing the efficiency of sample consumption. A femtosecond pulse from an X-ray free-electron laser then intersects with a droplet that contains protein crystals. (SLAC National Accelerator Laboratory)

    SLAC/LCLS

    2
    As the drops move forward, they are hit with pulses of visible light or treated with oxygen gas, which triggers different chemical reactions depending on the sample studied. (SLAC National Accelerator Laboratory)

    Biological samples studied with intense X-rays at free-electron lasers are destroyed within nanoseconds after they are exposed. Because of this, the samples need to be continually refreshed to allow the many images needed for an experiment to be obtained. Conventional methods use jets that supply a continuous stream of samples, but this can be very wasteful as the X-rays only interact with a tiny fraction of the injected material.

    To help address this issue, scientists at the Department of Energy’s Lawrence Berkeley National Laboratory, SLAC National Accelerator Laboratory, Brookhaven National Laboratory, and other institutes designed a new assembly-line system that rapidly replaces exposed samples by moving droplets along a miniature conveyor belt, timed to coincide with the arrival of the X-ray pulses.

    The droplet-on-tape system now allows the team to study the biochemical reactions in real-time from microseconds to seconds, revealing the stages of these complex reactions.

    In their approach, protein solution or crystals are precisely deposited in tiny liquid drops, made as ultrasound waves push the liquid onto a moving tape. As the drops move forward, they are hit with pulses of visible light or treated with oxygen gas, which triggers different chemical reactions depending on the sample studied. This allows the study of processes such as photosynthesis, which determines how plants absorb light from the sun and convert it into useable energy.

    Finally, powerful X-ray pulses from SLAC’s X-ray laser, the Linac Coherent Light Source (LCLS), probe the drops. In this study published in Nature Methods, the X-ray light scattered from the sample onto two different detectors simultaneously, one for X-ray crystallography and the other for X-ray emission spectroscopy. These are two complementary methods that provide information about the geometric and electronic structure of the catalytic sites of the proteins and allowed them to watch with atomic precision how the protein structures changed during the reaction.

    Below, see the conveyor belt in action at LCLS, a Department of Energy Office of Science User Facility.

    3
    Droplet-on-tape conveyor belt system delivers samples at the Linac Coherent Light Source (LCLS). (SLAC National Accelerator Laboratory)

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    SLAC Campus
    SLAC is a multi-program laboratory exploring frontier questions in photon science, astrophysics, particle physics and accelerator research. Located in Menlo Park, California, SLAC is operated by Stanford University for the DOE’s Office of Science.
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  • richardmitnick 2:36 pm on July 5, 2017 Permalink | Reply
    Tags: A Whole-Genome Sequenced Rice Mutant Resource for the Study of Biofuel Feedstocks, , Fast-neutron irradiation causes different types of mutations, , , Kitaake: a model rice variety with a short life cycle, LBNL   

    From LBNL: “A Whole-Genome Sequenced Rice Mutant Resource for the Study of Biofuel Feedstocks” 

    Berkeley Logo

    Berkeley Lab

    July 5, 2017
    Sarah Yang
    scyang@lbl.gov
    (510) 486-4575

    JBEI researchers create open-access web portal to accelerate functional genetic research in plants.

    1
    Genome-wide distribution of fast-neutron-induced mutations in the Kitaake rice mutant population (green). Even distribution of mutations is important to achieve saturation of the genome. Colored lines (center) represent translocations of DNA fragments from one chromosome to another. (Credit: Guotian Li and Rashmi Jain/Berkeley Lab).

    Rice is a staple food for over half of the world’s population and a model for studies of candidate bioenergy grasses such as sorghum, switchgrass, and Miscanthus. To optimize crops for biofuel production, scientists are seeking to identify genes that control key traits such as yield, resistance to disease, and water use efficiency.

    Populations of mutant plants, each one having one or more genes altered, are an important tool for elucidating gene function. With whole-genome sequencing at the single nucleotide level, researchers can infer the functions of the genes by observing the gain or loss of particular traits. But the utility of existing rice mutant collections has been limited by several factors, including the cultivars’ relatively long six-month life cycle and the lack of sequence information for most of the mutant lines.

    In a paper published in The Plant Cell, a team led by Pamela Ronald, a professor in the Genome Center and the Department of Plant Pathology at UC Davis and director of Grass Genetics at the Department of Energy’s (DOE’s) Joint BioEnergy Institute (JBEI), with collaborators from UC Davis and the DOE Joint Genome Institute (JGI), reported the first whole-genome sequenced fast-neutron induced mutant population of Kitaake, a model rice variety with a short life cycle.

    Kitaake (Oryza sativa L. ssp. japonica) completes its life cycle in just nine weeks and is not sensitive to photoperiod changes. This novel collection will accelerate functional genetic research in rice and other monocots, a type of flowering plant species that includes grasses.

    “Some of the most popular rice varieties people use right now only have two generations per year. Kitaake has up to four, which really speeds up functional genomics work,” said Guotian Li, a project scientist at Lawrence Berkeley National Laboratory (Berkeley Lab) and deputy director of Grass Genetics at JBEI.

    In a previously published pilot study [Molecular Plant], Li, Mawsheng Chern, and Rashmi Jain, co-first authors on The Plant Cell paper, demonstrated that fast-neutron irradiation produced abundant and diverse mutations in Kitaake, including single base substitutions, deletions, insertions, inversions, translocations, and duplications. Other techniques that have been used to generate rice mutant populations, such as the insertion of gene and chromosome segments and the use of gene editing tools like CRISPR-Cas9, generally produce a single type of mutation, Li noted.

    “Fast-neutron irradiation causes different types of mutations and gives different alleles of genes so we really can get something that’s not achievable from other collections,” he said.

    Whole-genome sequencing of this mutant population – 1,504 lines in total with 45-fold coverage – allowed the researchers to pinpoint each mutation at a single-nucleotide resolution. They identified 91,513 mutations affecting 32,307 genes, 58 percent of all genes in the roughly 389-megabase rice genome. A high proportion of these were loss-of-function mutations.

    Using this mutant collection, the Grass Genetics group identified an inversion affecting a single gene as the causative mutation for the short-grain phenotype in one mutant line with a population containing just 50 plants. In contrast, researchers needed more than 16,000 plants to identify the same gene using the conventional approach.

    “This comparison clearly demonstrates the power of the sequenced mutant population for rapid genetic analysis,” said Ronald.

    This high-density, high-resolution catalog of mutations, developed with JGI’s help, provides researchers opportunities to discover novel genes and functional elements controlling diverse biological pathways. To facilitate open access to this resource, the Grass Genetics group has established a web portal called KitBase, which allows users to find information related to the mutant collection, including sequence, mutation and phenotypic data for each rice line. Additional information about the database can be found through JGI.

    Additional Berkeley Lab scientists who contributed to this work include co-first authors Rashmi Jain and Mawsheng Chern; Tong Wei and Deling Ruan, both affiliated with JBEI’s Feedstocks Division and with Berkeley Lab’s Environmental Genomics and Systems Biology Division; Nikki Pham and Kyle Jones of JBEI’s Feedstocks Division; and Joel Martin, Wendy Schackwitz, Anna Lipzen, Diane Bauer, Yi Peng, and Kerrie Barry of the JGI.

    Support for the research at JBEI, a DOE Bioenergy Research Center, and JGI, a DOE Office of Science User Facility, was provided by DOE’s Office of Science. Additional support was provide by the National Institutes of Health and the National Science Foundation.

    See the full article here .

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  • richardmitnick 11:08 am on July 1, 2017 Permalink | Reply
    Tags: , , LBNL,   

    From Stanford Scope: “Researchers discover new mechanism involved in gene silencing” 

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    Stanford University

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    Scope blog

    June 30, 2017
    Jennifer Huber

    1
    No image caption or credit.

    Heterochromatin is a key player in gene regulation. This tightly packed complex of nuclear proteins and DNA is usually found in regions where genes are silenced. Unfortunately, how it works is not fully understood.

    Now, researchers from the Lawrence Berkeley National Laboratory have shown that heterochromatin organizes DNA into different physical compartments inside a cell nucleus to promote distinct genome functions. And it does this using liquid-liquid phase separation, the same mechanism that separates mixtures of oil and water, as recently reported in Nature.

    Previously, scientists thought that heterochromatin’s dense packing silenced genes by preventing regulatory proteins from gaining access. The theory was that the tightly wound strands made it difficult for the proteins to get to the genetic material inside. However, this didn’t explain why heterochromatin excludes some small proteins while admitting other large ones.

    The new study, using fruit flies and mouse cells, identified a different mechanism. The Berkeley Lab researchers observed two non-mixing liquids in the cell nucleus: one that contained silenced heterochromatin and another that contained DNA with expressed genes. They found that the heterochromatin droplets fused together like drops of oil in water, indicating that the distinct heterochromatin compartments arise through liquid-liquid phase separation.

    “We are excited about these findings because they explain a mystery that’s existed in the field for a decade,” said lead author Amy Strom, a biology graduate student at the University of California, Berkeley, in a recent news release. “That is, if compaction controls access to silenced sequences, how are other large proteins still able to get in? Chromatin organization by phase separation means that proteins are targeted to one liquid or the other based not on size, but on other physical traits, like charge, flexibility, and interaction partners.”

    The researchers hope a better understanding of how heterochromatin works will ultimately lead to improved gene therapy or other treatments that rely on accurate regulation of gene expression.

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    Scope is an award-winning blog founded in 2009 and produced by the Stanford University School of Medicine. If you’re curious about the latest advances in medicine and health and enjoy compelling, fresh and easily digestible news and features, then we’ve got just the thing. We’ve written quite a bit (7,000 posts and counting!), and we’re quite proud of it — so please enjoy.

    Leland and Jane Stanford founded the University to “promote the public welfare by exercising an influence on behalf of humanity and civilization.” Stanford opened its doors in 1891, and more than a century later, it remains dedicated to finding solutions to the great challenges of the day and to preparing our students for leadership in today’s complex world. Stanford, is an American private research university located in Stanford, California on an 8,180-acre (3,310 ha) campus near Palo Alto. Since 1952, more than 54 Stanford faculty, staff, and alumni have won the Nobel Prize, including 19 current faculty members

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  • richardmitnick 8:35 pm on June 28, 2017 Permalink | Reply
    Tags: , , , Katie Dunne, LBNL, , , ,   

    From LBNL: Women in STEM “Berkeley Lab Intern Finds Her Way in Particle Physics” Katie Dunne 

    Berkeley Logo

    Berkeley Lab

    June 27, 2017
    Theresa Duque
    tnduque@lbl.gov
    (510) 495-2418

    1
    Intern Katherine Dunne with mentor Maurice Garcia-Sciveres. (Credit: Marilyn Chung/Berkeley Lab)

    As a high school student in Birmingham, Alabama, Berkeley Lab Undergraduate Research (BLUR) intern Katie Dunne first dreamed of becoming a physicist after reading Albert Einstein’s biography, but didn’t know anyone who worked in science. “I felt like the people who were good at math and science weren’t my friends,” she said. So when it came time for college, she majored in English, and quickly grew dissatisfied because it wasn’t challenging enough. Eventually, she got to know a few engineers, but none of them were women, she recalled.

    She still kept physics in the back of her mind until she read an article about “The First Lady of Physics,” Chien-Shiung Wu, an experimental physicist who worked on the Manhattan Project, and later designed the “Wu experiment,” which proved that the conservation of parity is violated by weak interactions. “Two male theorists who proposed parity violation won the 1957 Nobel Prize in physics, and Wu did not,” Dunne said. “When I read about her, I decided that that’s what I want to do – design experiments.”

    So she put physics front and center, and about four years ago, transferred as a physics major to the City College of San Francisco. “With Silicon Valley nearby, there are many opportunities here to get work experience in instrumentation and electrical engineering,” Dunne said. In the summers of 2014 and 2015, she landed internships in the Human Factors division at NASA Ames Research Center in Mountain View, where she streamlined the development of a printed circuit board for active infrared illumination.

    But it wasn’t until she took a class in modern physics when she discovered her true passion – particle physics. “When we got to quantum physics, it was great. Working on the problems of quantum physics is exciting,” she said. “It’s so elegant and dovetails with math. It’s the ultimate mystery because we can’t observe quantum behavior.”

    When it came time to apply for her next summer internship in 2016, instead of reapplying for a position at NASA, she googled “ATLAS,” the name of a 7,000-ton detector for the Large Hadron Collider (LHC). Her search drummed up an article about Beate Heinemann, who, at the time, was a researcher with dual appointments at UC Berkeley and Berkeley Lab and was deputy spokesperson of the ATLAS collaboration. (Heinemann is also one of the 20 percent of female physicists working on the ATLAS experiment.)

    CERN/ATLAS detector

    When Dunne contacted Heinemann to ask if she would consider her for an internship, she suggested that she contact Maurice Garcia-Sciveres, a physicist at Berkeley Lab whose research specializes in pixel detectors for ATLAS, and who has mentored many students interested in instrumentation.

    Garcia-Sciveres invited Dunne to a meeting so she could see the kind of work that they do. “I could tell I would get a lot of hands-on experience,” she said. So she applied for her first internship with Garcia-Sciveres through the Community College Internship (CCI) program – which, like the BLUR internship program, is managed by Workforce Development & Education at Berkeley Lab – and started to work with his team on building prototype integrated circuit (IC) test systems for ATLAS as part of the High Luminosity Large Hadron Collider (HL-LHC) Project, an international collaboration headed by CERN to increase the LHC’s luminosity (rate of collisions) by a factor of 10 by 2020.

    3
    A quad module with a printed circuit board (PCB) for power and data interface to four FE-I4B chips. Dunne designed the PCB. (Credit: Katie Dunne/Berkeley Lab)

    “For the ATLAS experiment, we work with the Engineering Division to build custom electronics and integrated circuits for silicon detectors. Our work is focused on improving the operation, testing, and debugging of these ICs,” said Garcia-Sciveres.

    During Dunne’s first internship, she analyzed threshold scans for an IC readout chip, and tested their radiation hardness – or threshold for tolerating increasing radiation doses – at the Lab’s 88-Inch Cyclotron and at SLAC National Accelerator Laboratory. “Berkeley Lab is a unique environment for interns. They throw you in, and you learn on the job. The Lab gives students opportunities to make a difference in the field they’re working in,” she said.

    For Garcia-Sciveres, it didn’t take long for Dunne to prove she could make a difference for his team. Just after her first internship at Berkeley Lab, the results from her threshold analysis made their debut as data supporting his presentation at the 38th International Conference on High Energy Physics (ICHEP) in August 2016. “The results were from her measurements,” he said. “This is grad student-level work she’s been doing. She’s really good.”

    5
    Katie Dunne delivers a poster presentation in spring 2017. (Credit: Marilyn Chung/Berkeley Lab)

    After the conference, Garcia-Sciveres asked Dunne to write the now published proceedings (he and the other authors provided her with comments and suggested wording). And this past January, Dunne presented “Results of FE65-P2 Stability Tests for the High Luminosity LHC Upgrade” during the “HL-LHC, BELLE2, Future Colliders” session of the American Physical Society (APS) Meeting in Washington, D.C.

    This summer, for her third and final internship at the Lab, Dunne is working on designing circuit boards needed for the ATLAS experiment, and assembling and testing prototype multi-chip modules to evaluate system performance. She hopes to continue working on ATLAS when she transfers to UC Santa Cruz as a physics major in the fall, and would like to get a Ph.D. in physics one day. “I love knowing that the work I do matters. My internships and work experience as a research assistant at Berkeley Lab have made me more confident in the work I’m doing, and more passionate about getting things done and sharing my results,” she said.

    Go here for more information about internships hosted by Workforce Development & Education at Berkeley Lab, or contact them at education@lbl.gov.

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  • richardmitnick 1:14 pm on June 27, 2017 Permalink | Reply
    Tags: , Expanding the capacity of underwater communications could open up new avenues for exploration the researchers said, High-speed communications under seas, LBNL, , Remote probes in the oceans could send data without the need to surface   

    From LBNL: “Could This Strategy Bring High-Speed Communications to the Deep Sea?” 

    Berkeley Logo

    Berkeley Lab

    June 27, 2017
    Sarah Yang
    scyang@lbl.gov
    (510) 486-4575

    1
    Binary data representing the word “Berkeley” is converted by a digital circuit to information encoded in independent channels with different orbital angular momentum. The transducer array sends the information via a single acoustic beam with different patterns. The colors in the helical wavefront show different acoustic phases. (Credit: Chengzhi Shi/Berkeley Lab and UC Berkeley)

    A new approach to sending acoustic waves through water could potentially open up the world of high-speed communications to activities underwater, including scuba diving, remote ocean monitoring, and deep-sea exploration.

    By taking advantage of the dynamic rotation generated as acoustic waves travel, or the orbital angular momentum, researchers at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) were able to pack more channels onto a single frequency, effectively increasing the amount of information capable of being transmitted.

    They demonstrated this by encoding in binary form the letters that make up the word “Berkeley,” and transmitting the information along an acoustic signal that would normally carry less data. They describe their findings in a study published this week in the Proceedings of the National Academy of Sciences.

    “It’s comparable to going from a single-lane side road to a multi-lane highway,” said study corresponding author Xiang Zhang, senior faculty scientist at Berkeley Lab’s Materials Sciences Division and a professor at UC Berkeley. “This work has huge potential in high-speed acoustic communications.”

    While human activity below the surface of the sea increases, the ability to communicate underwater has not kept pace, limited in large part by physics. Microwaves are quickly absorbed in water, so transmissions cannot get far. Optical communication is no better since light gets scattered by underwater microparticles when traveling over long distances.

    Low frequency acoustics is the option that remains for long-range underwater communication. Applications for sonar abound, including navigation, seafloor mapping, fishing, offshore oil surveying, and vessel detection.

    2
    Chengzhi Shi checks the connections between the transducer array and the digital circuit. The experimental setup showed the potential of generating independent channels onto a single frequency to expand acoustic communications underwater. (Credit: Marilyn Chung/Berkeley Lab)

    However, the tradeoff with acoustic communication, particularly with distances of 200 meters or more, is that the available bandwidth is limited to a frequency range within 20 kilohertz. Frequency that low limits the rate of data transmission to tens of kilobits per second, a speed that harkens back to the days of dialup internet connections and 56-kilobit-per-second modems, the researchers said.

    “The way we communicate underwater is still quite primitive,” said Zhang. “There’s a huge appetite for a better solution to this.”

    The researchers adopted the idea of multiplexing, or combining different channels together over a shared signal. It is a technique widely used in telecommunications and computer networks, but multiplexing orbital angular momentum is an approach that had not been applied to acoustics until this study, the researchers said.

    As sound propagates, the acoustic wavefront forms a helical pattern, or vortex beam. The orbital angular momentum of this wave provides a spatial degree of freedom and independent channels upon which the researchers could encode data.

    “The rotation occurs at different speeds for channels with different orbital angular momenta, even while the frequency of the wave itself stays the same, making these channels independent of each other,” said study co-lead author Chengzhi Shi, a graduate student in Zhang’s lab. “That is why we could encode different bits of data in the same acoustic beam or pulse. We then used algorithms to decode the information from the different channels because they’re independent of each other.”

    3
    Letters are encoded onto independent channels, with the amplitudes and phases forming different patterns. (Credit: Chengzhi Shi/Berkeley Lab and UC Berkeley)

    The experimental setup, located at Berkeley Lab, consisted of a digital control circuit with an array of 64 transducers, together generating helical wavefronts to form different channels. The signals were sent out simultaneously via independent channels of the orbital angular momentum. They used a frequency of 16 kilohertz, which is within the range currently used in sonar. A receiver array with 32 sensors measured the acoustic waves, and algorithms were used to decode the different patterns.

    “We modulated the amplitude and phase of each transducer to form different patterns and to generate different channels on the orbital angular momentum,” said Shi. “For our experiment we used eight channels, so instead of sending just 1 bit of data, we can send 8 bits simultaneously. In theory, however, the number of channels provided by orbital angular momentum can be much larger.”

    The researchers noted that while the experiment was done in air, the physics of the acoustic waves is very similar for water and air at this frequency range.

    Expanding the capacity of underwater communications could open up new avenues for exploration, the researchers said. This added capacity could eventually make the difference between sending a text-only message and transmitting a high-definition feature film from below the ocean’s surface. Remote probes in the oceans could send data without the need to surface.

    “We know much more about space and our universe than we do about our oceans,” said Shi. “The reason we know so little is because we don’t have the probes to easily study the deep sea. This work could dramatically speed up our research and exploration of the oceans.”

    The other researchers on this team are co-lead author Marc Dubois and co-author Yuan Wang, both members of Zhang’s group.

    This research is supported by the UC Berkeley Ernest Kuh Chair Endowment, a UC Berkeley Graduate Student Fellowship, and the Gordon and Betty Moore Foundation.

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  • richardmitnick 5:11 pm on June 26, 2017 Permalink | Reply
    Tags: , , Electron beam lithography, Halide perovskites, LBNL, , ,   

    From LBNL: “New Class of ‘Soft’ Semiconductors Could Transform HD Displays” 

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    Berkeley Lab

    June 26, 2017
    Sarah Yang
    scyang@lbl.gov
    (510) 486-4575

    A new type of semiconductor may be coming to a high-definition display near you. Scientists at the Department of Energy’s Lawrence Berkeley National Laboratory (LBNL) have shown that a class of semiconductor called halide perovskites is capable of emitting multiple, bright colors from a single nanowire at resolutions as small as 500 nanometers.

    1
    Single nanowires shown emitting different colors. The top panel shows a cesium lead bromide (CsPbBr3)-cesium lead chloride (CsPbCl3) heterojunction simultaneously emitting green and blue lights, respectively, under UV excitation. The bottom panel shows a cesium lead iodide (CsPbI3)-cesium lead bromide-cesium lead chloride configuration emitting red, green, and blue lights, respectively. (Credit: Letian Dou/Berkeley Lab and Connor G. Bischak/UC Berkeley)

    The findings, published online this week in the early edition of the Proceedings of the National Academy of Sciences, represent a clear challenge to quantum dot displays that rely upon traditional semiconductor nanocrystals to emit light. It could also influence the development of new applications in optoelectronics, photovoltaics, nanoscopic lasers, and ultrasensitive photodetectors, among others.

    The researchers used electron beam lithography to fabricate halide perovskite nanowire heterojunctions, the junction of two different semiconductors. In device applications, heterojunctions determine energy level and bandgap characteristics, and are therefore considered a key building block of modern electronics and photovoltaics.

    The researchers pointed out that the lattice in halide perovskites is held together by ionic instead of covalent bonds. In ionic bonds, atoms of opposite charges are attracted and transfer electrons to each other. Covalent bonds, in contrast, occur when atoms share their electrons with each other.

    “With inorganic halide perovskites, we can easily swap the anions in the ionic bonds while maintaining the single crystalline nature of the materials,” said study principal investigator Peidong Yang, senior faculty scientist at Berkeley Lab’s Materials Sciences Division. “This allows us to easily reconfigure the structure and composition of the material. That’s why halide perovskites are considered soft lattice semiconductors. Covalent bonds, in contrast, are relatively robust and require more energy to change. Our study basically showed that we can pretty much change the composition of any segment of this soft semiconductor.”

    2
    A 2-D plate showing alternating cesium lead chloride (blue) and cesium lead bromide (green) segments. (Credit: Letian Dou/Berkeley Lab and Connor G. Bischak/UC Berkeley)

    In this case, the researchers tested cesium lead halide perovskite, and then they used a common nanofabrication technique combined with anion exchange chemistry to swap out the halide ions to create cesium lead iodide, cesium lead bromide, and cesium lead chloride perovskites.

    Each variation resulted in a different color emitted. Moreover, the researchers showed that multiple heterojunctions could be engineered on a single nanowire. They were able to achieve a pixel size down to 500 nanometers, and they determined that the color of the material was tunable throughout the entire range of visible light.

    The researchers said that the chemical solution-processing technique used to treat this class of soft, ionic-bonded semiconductors is far simpler than methods used to manufacture traditional colloidal semiconductors.

    “For conventional semiconductors, fabricating the junction is quite complicated and expensive,” said study co-lead author Letian Dou, who conducted the work as a postdoctoral fellow in Yang’s lab. “High temperatures and vacuum conditions are usually involved to control the materials’ growth and doping. Precisely controlling the materials composition and property is also challenging because conventional semiconductors are ‘hard’ due to strong covalent bonding.”

    To swap the anions in a soft semiconductor, the material is soaked in a special chemical solution at room temperature.

    “It’s a simple process, and it is very easy to scale up,” said Yang, who is also a professor of chemistry at UC Berkeley. “You don’t need to spend long hours in a clean room, and you don’t need high temperatures.”

    The researchers are continuing to improve the resolution of these soft semiconductors, and are working to integrate them into an electric circuit.

    Other co-lead authors on this paper are Christopher Kley, UC Berkeley postdoctoral fellow, and Minliang Lai, UC Berkeley graduate student. Dou is now an assistant professor of chemical engineering at Purdue University.

    The DOE Office of Science supported this work.

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  • richardmitnick 7:31 pm on June 21, 2017 Permalink | Reply
    Tags: , , Gene Therapy, , heterochromatin protein 1a (HP1a), LBNL   

    From LBNL: “Researchers Find New Mechanism for Genome Regulation” 

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    Berkeley Lab

    June 21, 2017
    Sarah Yang
    scyang@lbl.gov
    (510) 486-4575

    Berkeley Lab study could have implications for improving gene therapy.

    The same mechanisms that quickly separate mixtures of oil and water are at play when controlling the organization in an unusual part of our DNA called heterochromatin, according to a new study by researchers at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab).

    Researchers studying genome and cell biology provide evidence that heterochromatin organizes large parts of the genome into specific regions of the nucleus using liquid-liquid phase separation, a mechanism well known in physics but whose importance for biology has only recently been revealed.

    2
    Liquid-like fusion of heterochromatin protein 1a droplets is shown in the embryo of a fruit fly. (Credit: Amy Strom/Berkeley Lab)

    They present their findings June 21 in the journal Nature, addressing a long-standing question about how DNA functions are organized in space and time, including how genes are regulated to be silenced or expressed.

    “The importance of DNA sequences in health and disease has been clear for decades, but we only recently have come to realize that the organization of sections of DNA into different physical domains or compartments inside the nucleus is critical to promote distinct genome functions,” said study corresponding author, Gary Karpen, senior scientist at Berkeley Lab’s Biological Systems and Engineering Division.

    The long stretches of DNA in heterochromatin contain sequences that, for the most part, need to be silenced for cells to work properly. Scientists once thought that compaction of the DNA was the primary mechanism for controlling which enzymes and molecules gain access to the sequences. It was reasoned that the more tightly wound the strands, the harder it would be to get to the genetic material inside.

    That mechanism has been questioned in recent years by the discovery that some large protein complexes could get inside the heterochromatin domain, while smaller proteins can remain shut out.

    3
    Shown is purified heterochromatin protein 1a forming liquid droplets in an aqueous solution. On the right side, two drops fuse together over time. (Credit: Amy Strom/Berkeley Lab)

    In this new study of early Drosophila embryos, the researchers observed two non-mixing liquids in the cell nucleus: one that contained expressed genes, and one that contained silenced heterochromatin. They found that heterochromatic droplets fused together just like two drops of oil surrounded by water.

    In lab experiments, researchers purified heterochromatin protein 1a (HP1a), a main component of heterochromatin, and saw that this single component was able to recreate what they saw in the nucleus by forming liquid droplets.

    “We are excited about these findings because they explain a mystery that’s existed in the field for a decade,” said study lead author Amy Strom, a graduate student in Karpen’s lab. “That is, if compaction controls access to silenced sequences, how are other large proteins still able to get in? Chromatin organization by phase separation means that proteins are targeted to one liquid or the other based not on size, but on other physical traits, like charge, flexibility, and interaction partners.”

    The Berkeley Lab study, which used fruit fly and mouse cells, will be published alongside a companion paper in Nature led by UC San Francisco researchers, who showed that the human version of the HP1a protein has the same liquid droplet properties, suggesting that similar principles hold for human heterochromatin.

    4
    Mouse fibroblast cells expressing HP1alpha, the human version of heterochromatin protein 1a. A technique that highlights edges between two liquid phases reveals the liquid droplets in the nucleus. (Credit: Amy Strom/Berkeley Lab)

    Interestingly, this type of liquid-liquid phase separation is very sensitive to changes in temperature, protein concentration, and pH levels.

    “It’s an elegant way for the cell to be able to manipulate gene expression of many sequences at once,” said Strom.

    Other cellular structures, including some involved in disease, are also organized by phase separation.

    “Problems with phase separation have been linked to diseases such as dementia and certain neurodegenerative disorders,” said Karpen.

    He noted that as we age, biological molecules lose their liquid state and become more solid, accumulating damage along the way. Karpen pointed to diseases like Alzheimer’s and Huntington’s, in which proteins misfold and aggregate, becoming less liquid and more solid over time.

    “If we can better understand what causes aggregation, and how to keep things more liquid, we might have a chance to combat these types of disease,” Strom added.

    The work is a big step forward for understanding how DNA functions, but could also help researchers improve their ability to manipulate genes.

    “Gene therapy, or any treatment that relies on tight regulation of gene expression, could be improved by precisely targeting molecules to the right place in the nucleus,” says Karpen. “It is very difficult to target genes located in heterochromatin, but this understanding of the properties linked to phase separation and liquid behaviors could help change that and open up a third of the genome that we couldn’t get to before.”

    This includes targeting gene-editing technologies like CRISPR, which has recently opened up new doors for precise genome manipulation and gene therapy.

    Karpen and Strom have joint appointments at UC Berkeley’s Department of Molecular and Cell Biology. Other study co-authors include Mustafa Mir and Xavier Darzacq at UC Berkeley, and Alexander Emelyanov and Dmitry Fyodorov at the Albert Einstein College of Medicine in New York.

    The National Institutes of Health and the California Institute for Regenerative Medicine helped support this work.

    See the full article here .

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  • richardmitnick 5:46 pm on June 20, 2017 Permalink | Reply
    Tags: , , LBNL, , Superconducting undulators, ,   

    From LBNL: “R&D Effort Produces Magnetic Devices to Enable More Powerful X-ray Lasers” 

    Berkeley Logo

    Berkeley Lab

    June 20, 2017
    Glenn Roberts Jr.
    geroberts@lbl.gov
    (510) 486-5582

    Berkeley Lab demonstrates a record-setting magnetic field for a prototype superconducting undulator.

    1
    This Berkeley Lab-developed device, a niobium tin superconducting undulator prototype, set a record in magnetic field strength for a device of its kind. This type of undulator could be used to wiggle electron beams to emit light for a next generation of X-ray lasers.
    (Credit: Marilyn Chung/Berkeley Lab)

    Researchers at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) and Argonne National Laboratory have collaborated to design, build, and test two devices, called superconducting undulators, which could make X-ray free-electron lasers (FELs) more powerful, versatile, compact, and durable.

    X-ray FELs are powerful tools for studying the microscopic structure and other properties of samples, such as proteins that are key to drug design, exotic materials relevant to electronics and energy applications, and chemistry that is central to industrial processes like fuel production.

    The recent development effort was motivated by SLAC National Accelerator Laboratory’s upgrade of its Linac Coherent Light Source (LCLS), the nation’s only X-ray FEL.

    SLAC LCLS-II

    This upgrade, now underway, is known as LCLS-II. All existing X-ray FELS, including both LCLS and LCLS-II, use permanent magnet undulators to generate intense pulses of X-rays. These devices produce X-ray light by passing high-energy bunches of electrons through alternating magnetic fields produced by a series of permanent magnets.

    Superconducting undulators (SCUs) offer another technical solution and are considered among the most promising technologies to improve the performance of the next generation FELs, and of other types of light sources, such as Berkeley Lab’s Advanced Light Source (ALS) and Argonne’s Advanced Photon Source (APS).

    LBNL/ALS

    ANL APS

    SCUs replace the permanent magnets in the undulator with superconducting coils. The prototype SCUs have successfully produced stronger magnetic fields than conventional undulators of the same size. Higher fields, in turn, can produce higher-energy free-electron laser light to open up a broader range of experiments.

    Berkeley Lab’s 1.5-meter-long prototype undulator, which uses a superconducting material known as niobium-tin (Nb3Sn), set a record in magnetic field strength for a device of its design during testing at the Lab in September 2016.

    “This is a much-anticipated innovation,” agreed Wim Leemans, Director, Accelerator Technology and Applied Physics (ATAP) . “Higher performance in a smaller footprint is something that benefits everyone – the laboratories that host the facilities, the funding agencies, and above all, the user community.”

    Argonne’s test of another superconducting material, niobium-titanium, successfully reached its performance goal, and additionally passed a bevy of quality tests. Niobium-titanium has a lower maximum magnetic field strength than niobium-tin, but is further along in its development.

    3
    The superconducting undulator R&D project at Berkeley Lab was a team effort. Among the contributors: (from left) Heng Pan, Jordan Taylor, Soren Prestemon, Ross Schlueter, Diego Arbelaez, Jim Swanson, Ahmet Pekedis, Scott Myers, Tom Lipton, and Xiaorong Wang. (Credit: Marilyn Chung/Berkeley Lab)

    Researchers at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) and Argonne National Laboratory have collaborated to design, build, and test two devices, called superconducting undulators, which could make X-ray free-electron lasers (FELs) more powerful, versatile, compact, and durable.

    X-ray FELs are powerful tools for studying the microscopic structure and other properties of samples, such as proteins that are key to drug design, exotic materials relevant to electronics and energy applications, and chemistry that is central to industrial processes like fuel production.

    The recent development effort was motivated by SLAC National Accelerator Laboratory’s upgrade of its Linac Coherent Light Source (LCLS), the nation’s only X-ray FEL. This upgrade, now underway, is known as LCLS-II. All existing X-ray FELS, including both LCLS and LCLS-II, use permanent magnet undulators to generate intense pulses of X-rays. These devices produce X-ray light by passing high-energy bunches of electrons through alternating magnetic fields produced by a series of permanent magnets.

    Superconducting undulators (SCUs) offer another technical solution and are considered among the most promising technologies to improve the performance of the next generation FELs, and of other types of light sources, such as Berkeley Lab’s Advanced Light Source (ALS) and Argonne’s Advanced Photon Source (APS).

    SCUs replace the permanent magnets in the undulator with superconducting coils. The prototype SCUs have successfully produced stronger magnetic fields than conventional undulators of the same size. Higher fields, in turn, can produce higher-energy free-electron laser light to open up a broader range of experiments.

    Berkeley Lab’s 1.5-meter-long prototype undulator, which uses a superconducting material known as niobium-tin (Nb3Sn), set a record in magnetic field strength for a device of its design during testing at the Lab in September 2016.

    “This is a much-anticipated innovation,” agreed Wim Leemans, Director, Accelerator Technology and Applied Physics (ATAP) . “Higher performance in a smaller footprint is something that benefits everyone – the laboratories that host the facilities, the funding agencies, and above all, the user community.”

    Argonne’s test of another superconducting material, niobium-titanium, successfully reached its performance goal, and additionally passed a bevy of quality tests. Niobium-titanium has a lower maximum magnetic field strength than niobium-tin, but is further along in its development.
    Photo – The superconducting undulator R&D project at Berkeley Lab was a team effort. Among the contributors: (from left) Heng Pan, Jordan Taylor, Soren Prestemon, Ross Schlueter, Diego Arbelaez, Jim Swanson, Ahmet Pekedis, Scott Myers, Tom Lipton, and Xiaorong Wang. (Credit: Marilyn Chung/Berkeley Lab)

    The superconducting undulator R&D project at Berkeley Lab was a team effort. Among the contributors: (from left) Heng Pan, Jordan Taylor, Soren Prestemon, Ross Schlueter, Diego Arbelaez, Jim Swanson, Ahmet Pekedis, Scott Myers, Tom Lipton, and Xiaorong Wang. (Credit: Marilyn Chung/Berkeley Lab)

    “The superconducting technology in general, and especially with the niobium tin, lived up to its promise of being the highest performer,” said Ross Schlueter, Head of the Magnetics Department in Berkeley Lab’s Engineering Division. “We’re very excited about this world record. This device allows you to get a much higher photon energy” from a given electron beam energy.

    “We have expertise here both in free-electron laser undulators, as demonstrated in our role in leading the construction of LCLS-II’s undulators, and in synchrotron undulator development at the ALS,” noted Soren Prestemon, Director of the Berkeley Center for Magnet Technology (BCMT), which brings together the Accelerator Technology and Applied Physics Division (ATAP) and Engineering Division, to design and build a range of magnetic devices for scientific, medical, and other applications.

    “The Engineering Division has a long history of forefront research on undulators, and this work continues that tradition,” states Henrik von der Lippe, Director, Engineering Division.

    Diego Arbelaez, the lead engineer in the development of Berkeley Lab’s device, said earlier work at the Lab in building superconducting undulator prototypes for a different project were useful in informing the latest design, though there were still plenty of challenges.

    Niobium-tin is a brittle material that cannot be drawn into a wire. For practical use, a pliable wire, which contains the components that will form niobium-tin when heat-treated, is used for winding the undulator coils. The full undulator coil is then heat-treated in a furnace at 1,200 degrees Fahrenheit.

    The niobium-tin wire is wound around a steel frame to form tightly wrapped coils in an alternating arrangement. The precision of the winding is critical for the performance of the device. Arbelaez said, “One of the questions was whether you can maintain precision in its winding even though you are going through these large temperature variations.”

    After the heat treatment, the coils are placed in a mold and impregnated with epoxy to hold the superconducting coils in place. To achieve a superconducting state and demonstrate its record-setting performance, the device was immersed in a bath of liquid helium to cool it down to about minus 450 degrees Fahrenheit.

    4
    Ahmet Pekedis, left, and Diego Arbelaez inspect the completed niobium tin undulator prototype. (Credit: Marilyn Chung/Berkeley Lab)

    Another challenge was in developing a fast shutoff to prevent catastrophic failure during an event known as “quenching.” During a quench, there is a sudden loss of superconductivity that can be caused by a small amount of heat generation. Uncontrolled quenching could lead to rapid heating that might damage the niobium-tin and surrounding copper and ruin the device.

    This is a critical issue for the niobium-tin undulators due to the extraordinary current densities they can support. Berkeley Lab’s Marcos Turqueti led the effort to engineer a quench-protection system that can detect the occurrence of quenching within a couple thousandths of a second and shut down its effects within 10 thousandths of a second.

    Arbelaez also helped devise a system to correct for magnetic-field errors while the undulator is in its superconducting state.

    SLAC’s Paul Emma, the accelerator physics lead for LCLS-II, coordinated the superconducting undulator development effort.

    Emma said that the niobium-tin superconducting undulator developed at Berkeley Lab shows potential but may require more extensive continuing R&D than Argonne’s niobium-titanium prototype. Argonne earlier developed superconducting undulators that are in use at its APS, and Berkeley Lab also hopes to add superconducting undulators at its ALS.

    “With superconducting undulators,” Emma said, “you don’t necessarily lower the cost but you get better performance for the same stretch of undulator.”

    5
    A close-up view of the superconducting undulator prototype developed at Berkeley Lab. To construct the undulator, researchers wound a pliable wire in alternating coils around a steel frame. The pliable wire was baked to form a niobium-tin compound that is very brittle but can achieve high magnetic fields when chilled to superconducting temperatures. (Credit: Marilyn Chung/Berkeley Lab)

    A superconducting undulator of an equivalent length to a permanent magnetic undulator could produce light that is at least two to three times – perhaps up to 10 times – more powerful, and could also access a wider range in X-ray wavelengths, Emma said, producing a more efficient FEL.

    Superconducting undulators also have no macroscopic moving parts, so they could conceivably be tuned more quickly with high precision. Superconductors also are far less prone to damage by high-intensity radiation than permanent-magnet materials, a significant issue in high-power accelerators such as those that will be installed for LCLS-II.

    There appears to be a clear path forward to developing superconducting undulators for upgrades of existing and new X-ray free-electron lasers, Emma said, and for other types of light sources.

    “Superconducting undulators will be the technology we go to eventually, whether it’s in the next 10 or 20 years,” he said. “They are powerful enough to produce the light we are going to need – I think it’s going to happen. People know it’s a big enough step, and we’ve got to get there.”

    James Symons, Berkeley Lab’s Associate Director for Physical Sciences, said, “We look forward to building on this effort by furthering our R&D on superconducting undulator systems.

    The Advanced Light Source, Advanced Photon Source, and Linac Coherent Light Source are DOE Office of Science User Facilities. The development of the superconducting undulator prototypes was supported by the DOE’s Office of Science.”

    See the full article here .

    Please help promote STEM in your local schools.

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  • richardmitnick 7:02 am on June 20, 2017 Permalink | Reply
    Tags: Dynamic self-assembly under non-equilibrium is not only important in physics but also in our living world, LBNL, , Self-Heal, Sound Waves Direct Particles to Self-Assemble   

    From LBNL: “Sound Waves Direct Particles to Self-Assemble, Self-Heal” 

    Berkeley Logo

    Berkeley Lab

    June 19, 2017
    Sarah Yang
    scyang@lbl.gov
    (510) 486-4575

    1
    Close up photograph of the self-assembling particles in the clear acrylic tube. These particles consist of cut plastic straws (blue) sealed to a flat plastic chip (black), which float on top of a water-glycerin solution. (Credit: Chad Ropp/Berkeley Lab).

    An elegantly simple experiment with floating particles self-assembling in response to sound waves has provided a new framework for studying how seemingly lifelike behaviors emerge in response to external forces.

    Close up photograph of the self-assembling particles in the clear acrylic tube. These particles consist of cut plastic straws (blue) sealed to a flat plastic chip (black), which float on top of a water-glycerin solution. (Credit: Chad Ropp/Berkeley Lab)

    Scientists at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) demonstrated how particles, floating on top of a glycerin-water solution, synchronize in response to acoustic waves blasted from a computer speaker.

    The study, published today (Monday, June 19) in the journal Nature Materials, could help address fundamental questions about energy dissipation and how it allows living and nonliving systems to adapt to their environment when they are out of thermodynamic equilibrium.

    2
    Photograph of the experimental setup, which consists of a 2-meter-long acrylic tube with funnels at both ends to direct the sound from a computer speaker (bottom left) out to absorbing media (top right). A web camera is set above the setup to track the motion of the particles, and a microphone is inserted into the output funnel to measure the transmission spectrum in time. Credit: Chad Ropp/Berkeley Lab

    “Dynamic self-assembly under non-equilibrium is not only important in physics, but also in our living world,” said Xiang Zhang, corresponding author of the paper and a senior faculty scientist at Berkeley Lab’s Materials Sciences Division with a joint appointment at UC Berkeley. “However, the underlying principles governing this are only partially understood. This work provides a simple yet elegant platform to study and understand such phenomena.”

    To hear some physicists describe it, this state of non-equilibrium, characterized by the ability to constantly change and evolve, is the essence of life. It applies to biological systems, from cells to ecosystems, as well as to certain nonbiological systems, such as weather or climate patterns. Studying non-equilibrium systems gets theorists a bit closer to understanding how life – particularly intelligent life – emerges.

    However, non-equilibrium systems are complicated and hard to study because they are open systems, Zhang said. He noted that physicists like to study things that are stable and in closed systems.

    Transient response of dynamic self-assembly. Top portion shows the position of the particles (blue) while they self-assemble in response to sound that is incident from the left (red arrow). Bottom portion shows the time response of the transmission spectrum of the system (blue), which is compared to theoretical spectrum (black). The red line denotes the wavelength of the monotone input sound. (Credit: Chad Ropp/Berkeley Lab)

    “We show that individually ‘dumb’ particles can self-organize far from equilibrium by dissipating energy and emerge with a collective trait that is dynamically adaptive to and reflective of their environment,” said study co-lead author Chad Ropp, a postdoctoral researcher in Zhang’s group. “In this case, the particles followed the ‘beat’ of a sound wave generated from a computer speaker.”

    Notably, after the researchers intentionally broke up the particle party, the pieces would reassemble, showing a capacity to self-heal.

    Ropp noted that this work could eventually lead to a wide variety of “smart” applications, such as adaptive camouflage that responds to sound and light waves, or blank-slate materials whose properties are written on demand by externally controlled drives.

    While previous studies have shown that particles are capable of self-assembly in response to an external force, this paper presents a general framework that researchers can use to study the mechanisms of adaptation in non-equilibrium systems.

    “The distinction in our work is that we can predict what happens – how the particles will behave – which is unexpected,” said another co-lead author Nicolas Bachelard, who is also a postdoctoral researcher in Zhang’s group.

    As the sound waves traveled at a frequency of 4 kilohertz, the scattering particles moved along at about 1 centimeter per minute. Within 10 minutes, the collective pattern of the particles emerged, where the distance between the particles was surprisingly non-uniform. The researchers found that the self-assembled particles exhibited a phononic bandgap – a frequency range in which acoustic waves cannot pass – whose edge was inextricably linked, or “enslaved,” to the 4 kHz input.

    “This is a characteristic that was not present with the individual particles,” said Bachelard. “It only appeared when the particles collectively organized, which is why we call this an emergent property of our structure under non-equilibrium conditions.”

    The experimental design could hardly have been simpler. For the waveguide, the researchers used a 2-meter-long acrylic tube that contained a 5-millimeter-deep pool of a glycerin-water solution. The particles were made from straws floating on top of a flat piece of plastic, and the sound source came from off-the-shelf computer speakers that researchers directed into the tube via a plastic funnel. Measuring the sound waves proved to be the most technical part of the experiment.

    “This is something you could do yourself in your garage,” said Ropp. “It was a dirt-cheap experiment with parts that are available at your corner hardware store. At one point, we needed bigger straws, so I went out and bought some boba tea. The setup was extremely simple, but it showed the physics beautifully.”

    The experiment focused on acoustic waves because soundproofing was easier to achieve, but the principles underlying the behavior they observed would be applicable to any wave system, the researchers said.

    This fundamental research could form the basis for developing intelligent networks that perform simple non-algorithmic computation, with a future toward systems that perform sentient-like decision making, the researchers said.

    “I can think of parallels to artificial brains, with sections that respond to different frequency ‘brain waves’ that are malleable and reconfigurable,” said Ropp.

    This work was supported by the Office of Naval Research and DOE’s Office of Science.

    See the full article here .

    Please help promote STEM in your local schools.

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

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