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  • richardmitnick 5:55 pm on October 16, 2014 Permalink | Reply
    Tags: , , Brookhaven National Labs, ,   

    From BNL: “Scientists Map Key Moment in Assembly of DNA-Splitting Molecular Machine” 

    Brookhaven Lab

    October 15, 2014
    Justin Eure, (631) 344-2347 or Peter Genzer, (631) 344-3174

    The proteins that drive DNA replication—the force behind cellular growth and reproduction—are some of the most complex machines on Earth. The multistep replication process involves hundreds of atomic-scale moving parts that rapidly interact and transform. Mapping that dense molecular machinery is one of the most promising and challenging frontiers in medicine and biology.

    Now, scientists have pinpointed crucial steps in the beginning of the replication process, including surprising structural details about the enzyme that “unzips” and splits the DNA double helix so the two halves can serve as templates for DNA duplication.

    The research combined electron microscopy, perfectly distilled proteins, and a method of chemical freezing to isolate specific moments at the start of replication. The study—authored by scientists from the U.S. Department of Energy’s Brookhaven National Laboratory, Stony Brook University, Cold Spring Harbor Laboratory, and Imperial College, London—published on Oct. 15, 2014, in the journal Genes and Development.

    “The genesis of the DNA-unwinding machinery is wonderfully complex and surprising,” said study coauthor Huilin Li, a biologist at Brookhaven Lab and Stony Brook University. “Seeing this helicase enzyme prepare to surround and unwind the DNA at the molecular level helps us understand the most fundamental process of life and how that process might go wrong. Errors in copying DNA are found in certain cancers, and this work could one day help develop new treatment methods that stall or break dangerous runaway machinery.”

    The research picks up where two previous studies by Li and colleagues left off. They first determined the structure of the “Origin Recognition Complex” (ORC), a protein that identifies and attaches to specific DNA sites to initiate the entire replication process. The second study revealed how the ORC recruits, cracks open, and installs a crucial ring-shaped protein structure (Mcm2-7) that lies at the core of the helicase enzyme.

    But DNA replication is a bi-directional process with two helicases moving in opposite directions. The key question, then, was how does a second helicase core get recruited and loaded onto the DNA in the opposite orientation of the first?

    dr
    Three-dimensional model (based on electron microscopy data) of the double-ring structure loaded onto a DNA helix.

    “To our surprise, we found an intermediate structure with one ORC binding two rings,” said Brookhaven Lab biologist and lead author Jingchuan Sun. “This discovery suggests that a single ORC, rather than the commonly believed two-ORC system, loads both helicase rings.”

    One step further along, the researchers also determined the molecular architecture of the final double-ring structure left behind after the ORC leaves the system, offering a number of key biological insights.

    “We now have clues to how that double-ring structure stably lingers until the cell enters the DNA-synthesis phase much later on in replication,” said study coauthor Christian Speck of Imperial College, London. “This study revealed key regulatory principles that explain how the helicase activity is initially suppressed and then becomes reactivated to begin its work splitting the DNA.”

    three
    Precision methods, close collaboration
    Collaborating scientists and study coauthors Zuanning Yuan of Stony Brook University (standing), Huilin Li of Stony Brook and Brookhaven Lab (seated, back), and Jingchuan Sun of Brookhaven Lab (seated, front) examining protein structures.

    Examining these fleeting molecular structures required mastery of biology, chemistry, and electron microscopy techniques.

    “This three-way collaboration took advantage of each lab’s long standing collaboration and expertise,” said study coauthor Bruce Stillman of Cold Spring Harbor. “Imperial College and Cold Spring Harbor handled the challenging material preparation and functional characterization, while Brookhaven and Stony Brook led the sophisticated molecular imaging and three-dimensional image reconstruction.”

    The researchers used proteins from baker’s yeast—a model organism for the more complex systems found in animals. The scientists isolated the protein mechanisms involved in replication and removed structures that might otherwise complicate the images.

    Once the isolated proteins were mixed with DNA, the scientists injected chemicals to “freeze” the binding and recruitment process at intervals of 2, 7, and 30 minutes.

    They then used an electron microscope at Brookhaven to pin down the exact structures at each targeted moment in a kind of molecular time-lapse. Rather than the light used in a traditional microscope, this technique uses focused beams of electrons to illuminate a sample and form images with atomic resolution. The instrument produces a large number of two-dimensional electron beam images, which a computer then reconstructs into three-dimensional structure.

    “This technique is ideal because we’re imaging relatively massive proteins here,” Li said. “A typical protein contains three hundred amino acids, but these DNA replication mechanisms consist of tens of thousands of amino acids. The entire structure is about 20-nanometers across, compared to 4 nanometers for an average protein.”

    Unraveling the DNA processes at the most fundamental level, the focus of this team’s work, could have far-reaching implications.

    “The structural knowledge may help others engineer small molecules that inhibit DNA replication at specific moments, leading to new disease prevention or treatment techniques,” Li said.

    Additional collaborators on this research include Alejandra Fernandez, Alberto Riera, and Silvia Tognetti of the MRC Clinical Science Centre of Imperial College, London; and Zuanning Yuan of Stony Brook University.

    The research was funded by the National Institutes of Health (GM45436, GM74985) and the United Kingdom Medical Research Council.

    See the full article here.

    BNL Campus

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world.Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
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  • richardmitnick 2:41 pm on October 14, 2014 Permalink | Reply
    Tags: , Brookhaven National Labs, , ,   

    From BNL: “Unstoppable Magnetoresistance” 

    Brookhaven Lab

    October 14, 2014
    Tien Nguyen

    Mazhar Ali, a fifth-year graduate student in the laboratory of Bob Cava, the Russell Wellman Moore Professor of Chemistry at Princeton University, has spent his academic career discovering new superconductors, materials coveted for their ability to let electrons flow without resistance. While testing his latest candidate, the semimetal tungsten ditelluride (WTe2), he noticed a peculiar result.

    Ali applied a magnetic field to a sample of WTe2, one way to kill superconductivity if present, and saw that its resistance doubled. Intrigued, Ali worked with Jun Xiong, a student in the laboratory of Nai Phuan Ong, the Eugene Higgins Professor of Physics at Princeton, to re-measure the material’s magnetoresistance, which is the change in resistance as a material is exposed to stronger magnetic fields.

    two
    Mazhar Ali (left) and Steven Flynn (right), co-authors on the Nature article
    Photo credit: C. Todd Reichart

    “They have unique capabilities at Brookhaven. One is that they can measure diffraction at 10 Kelvin (-441 °F).”
    — Bob Cava, Princeton University

    “He noticed the magnetoresistance kept going up and up and up—that never happens.” said Cava. The researchers then exposed WTe2 to a 60-tesla magnetic field, close to the strongest magnetic field mankind can create, and observed a magnetoresistance of 13 million percent. The material’s magnetoresistance displayed unlimited growth, making it the only known material without a saturation point. The results were published on September 14 in the journal Nature.

    Electronic information storage is dependent on the use of magnetic fields to switch between distinct resistivity values that correlate to either a one or a zero. The larger the magnetoresistance, the smaller the magnetic field needed to change from one state to another, Ali said. Today’s devices use layered materials with so-called “giant magnetoresistance,” with changes in resistance of 20,000 to 30,000 percent when a magnetic field is applied. “Colossal magnetoresistance” is close to 100,000 percent, so for a magnetoresistance percentage in the millions, the researchers hoped to coin a new term.

    cry.
    Crystal Structure of WTe2. Image credit: Nature

    Their original choice was “ludicrous” magnetoresistance, which was inspired by “ludicrous speed,” the fictional form of fast-travel used in the comedy “Spaceballs.” They even included an acknowledgement to director Mel Brooks. After other lab members vetoed “ludicrous,” the researchers considered “titanic” before Nature editors ultimately steered them towards the term “large magnetoresistance.”

    Terminology aside, the fact remained that the magnetoresistance values were extraordinarily high, a phenomenon that might be understood through the structure of WTe2. To look at the structure with an electron microscope, the research team turned to Jing Tao, a researcher at Brookhaven National Laboratory.

    jt
    Jing Tao

    “Jing is a great microscopist. They have unique capabilities at Brookhaven,” Cava said. “One is that they can measure diffraction at 10 Kelvin (-441 °F). Not too many people on Earth can do that, but Jing can.”

    Electron microscopy experiments revealed the presence of tungsten dimers, paired tungsten atoms, arranged in chains responsible for the key distortion from the classic octahedral structure type. The research team proposed that WTe2 owes its lack of saturation to the nearly perfect balance of electrons and electron holes, which are empty docks for traveling electrons. Because of its structure, WTe2 only exhibits magnetoresistance when the magnetic field is applied in a certain direction. This could be very useful in scanners, where multiple WTe2 devices could be used to detect the position of magnetic fields, Ali said.

    “Aside from making devices from WTe2, the question to ask yourself as a scientist is: How can it be perfectly balanced, is there something more profound,” Cava said.

    See the full article here.

    BNL Campus

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world.Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
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  • richardmitnick 3:12 pm on October 10, 2014 Permalink | Reply
    Tags: , Brookhaven National Labs, , Science Friday   

    From Science Friday via BNL: "How to Make Quark Soup" 

    Brookhaven Lab

    scifri

    Watch, enjoy, learn

    BNL Campus

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world.Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
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  • richardmitnick 2:18 pm on October 10, 2014 Permalink | Reply
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    From BNL: “Researchers Pump Up Oil Accumulation in Plant Leaves” 

    Brookhaven Lab

    October 7, 2014
    Karen McNulty Walsh, (631) 344-8350 or Peter Genzer, (631) 344-3174

    Increasing the oil content of plant biomass could help fulfill the nation’s increasing demand for renewable energy feedstocks. But many of the details of how plant leaves make and break down oils have remained a mystery. Now a series of detailed genetic studies conducted at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory and published in The Plant Cell reveals previously unknown biochemical details about those metabolic pathways—including new ways to increase the accumulation of oil in leaves, an abundant source of biomass for fuel production.

    Using these methods, the scientists grew experimental Arabidopsis plants whose leaves accumulated 9 percent oil by dry weight, which represents an approximately 150-fold increase in oil content compared to wild type leaves.

    “This is an unusually high level of oil accumulation for plant vegetative tissue,” said Brookhaven Lab biochemist Changcheng Xu, who led the research team. “In crop plants, whose growth time is longer, if the rate of oil accumulation is the same we could get much higher oil content—possibly as high as 40 percent by weight,” he said.

    And when it comes to growing plants for biofuels, packing on the calories is the goal, because energy-dense oils give more “bang per bushel” than less-energy-dense leaf carbohydrates.
    Deciphering biochemical pathways

    The key to increasing oil accumulation in these studies was to unravel the details of the biochemical pathways involved in the conversion of carbon into fatty acids, the storage of fatty acids as oil, and the breakdown of oil in leaves. Prior to this research, scientists did not know that these processes were so intimately related.

    “Our method resulted in an unusually high level of oil accumulation in plant vegetative tissue.”
    — Brookhaven Lab biochemist Changcheng Xu

    “We previously thought that oil storage and oil degradation were alternative fates for newly synthesized fatty acids—the building blocks of oils,” said Brookhaven biochemist John Shanklin, a collaborator on the studies.

    To reveal the connections, Brookhaven’s Jillian Fan and other team members used a series of genetic tricks to systematically disable an alphabet soup of enzymes—molecules that mediate a cell’s chemical reactions—to see whether and how each had an effect in regulating the various biochemical conversions. They also used radiolabeled versions of fatty acids to trace their paths and learn how quickly they move through the pathway. They then used the findings to map out how the processes take place inside different subcellular structures, some of which you might recognize from high school science classes: the chloroplast, endoplasmic reticulum, storage droplets, and the peroxisome.

    team
    Brookhaven researchers Jilian Fan, John Shanklin, and Changcheng Xu have developed a method for getting experimental plants to accumulate more leaf oil. Their strategy could have a significant impact on the production of biofuels.

    “Our goal was to test and understand all the components of the system to fully understand how fatty acids, which are produced in the chloroplasts, are broken down in the peroxisome,” Xu said.

    Key findings

    syn
    Details of the oil synthesis and breakdown pathways within plant leaf cells: Fatty acids (FA) synthesized within chloroplasts go through a series of reactions to be incorporated into lipids (TAG) within the endoplasmic reticulum (ER); lipid droplets (LD) store lipids such as oils until they are broken down to release fatty acids into the cytoplasm; the fatty acids are eventually transported into the peroxisome for oxidation. This detailed metabolic map pointed to a new way to dramatically increase the accumulation of oil in plant leaves — blocking the SDP1 enzyme that releases fatty acids from lipid droplets in plants with elevated fatty acid synthesis. If this strategy works in biofuel crops, it could dramatically increase the energy content of biomass used to make biofuels.

    The research revealed that there is no direct pathway for fatty acids to move from the chloroplasts to the peroxisome as had previously been assumed. Instead, many complex reactions occur within the endoplasmic reticulum to first convert the fatty acids through a series of intermediates into plant oils. These oils accumulate in storage droplets within the cytoplasm until another enzyme breaks them down to release the fatty acid building blocks. Yet another enzyme must transport the fatty acids into the peroxisome for the final stages of degradation via oxidation. The amount of oil that accumulates at any one time represents a balance between the pathways of synthesis and degradation.

    Some previous attempts to increase oil accumulation in leaves have focused on disrupting the breakdown of oils by blocking the action of the enzyme that transports fatty acids into the peroxisome. The reasoning was that the accumulation of fatty acids would have a negative feedback on oil droplet breakdown. High levels of fatty acids remaining in the cytoplasm would inhibit the further breakdown of oil droplets, resulting in higher oil accumulation.

    That idea works to some extent, Xu said, but the current research shows it has negative effects on the overall health of the plants. “Plants don’t grow as well and there can be other defects,” he said.

    Based on their new understanding of the detailed biochemical steps that lead to oil breakdown, Xu and his collaborators explored another approach—namely disabling the enzyme one step back in the metabolic process, the one that breaks down oil droplets to release fatty acids.

    “If we knock out this enzyme, known as SDP1, we get a large amount of oil accumulating in the leaves,” he said, “and without substantial detrimental effects on plant growth.”

    “This research points to a new and different way to accumulate oil in leaves from that being tried in other labs,” Xu said. “In addition, the strategy differs fundamentally from other strategies that are based on adding genes, whereas our strategy is based on disabling or inactivating genes through simple mutations. This work provides a very promising platform for engineering oil production in a non-genetically modified way.”

    “This work provides another example of how research into basic biochemical mechanisms can lead to knowledge that has great promise to help solve real world problems,” concluded Shanklin.

    This research was conducted by Xu in collaboration with Jilian Fan and Chengshi Yan and John Shanklin of Brookhaven’s Biosciences Department, and Rebecca Roston, now at the University of Nebraska, Lincoln. The work was funded by the DOE Office of Science and made use of a confocal microscope at Brookhaven Lab’s Center for Functional Nanomaterials, a DOE Office of Science user facility.

    See the full article here.

    BNL Campus

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world.Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
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  • richardmitnick 2:43 pm on October 3, 2014 Permalink | Reply
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    From BNL: “Brookhaven and the Daya Bay Neutrino Experiment” 

    Brookhaven Lab

    October 1, 2014
    Karen McNulty Walsh

    The Daya Bay Collaboration, an international group of scientists studying the subtle transformations of subatomic particles called neutrinos, is publishing its first results on the search for a so-called sterile neutrino, a possible new type of neutrino beyond the three known neutrino “flavors,” or types. The existence of this elusive particle, if proven, would have a profound impact on our understanding of the universe, and could impact the design of future neutrino experiments. The new results, appearing in the journal Physical Review Letters, show no evidence for sterile neutrinos in a previously unexplored mass range. Read the collaboration press release.

    db
    Daya Bay
    Daya Bay
    The U.S. Department of Energy’s Brookhaven National Laboratory plays multiple roles in the Daya Bay experiment, ranging from management to data analysis. In addition to coordinating detector engineering and design efforts and developing software and analysis techniques, Brookhaven scientists perfected the “recipe” for a very special, chemically stable liquid that fills Daya Bay’s detectors and interacts with antineutrinos. This work at Daya Bay builds on a legacy of breakthrough neutrino research by Brookhaven Lab that has resulted in two Nobel Prizes in Physics.

    team
    Members of the BNL team on the Daya Bay Neutrino Project include: (seated, from left) Penka Novakova, Laurie Littenberg, Steve Kettell, Ralph Brown, and Bob Hackenburg; (standing, from left) Zhe Wang, Chao Zhang, Jiajie Ling, David Jaffe, Brett Viren, Wanda Beriguete, Ron Gill, Mary Bishai, Richard Rosero, Sunej Hans, and Milind Diwan. Missing from the picture are: Donna Barci, Wai-Ting Chan, Chellis Chasman, Debbie Kerr, Hide Tanaka, Wei Tang, Xin Qian, Minfang Yeh, and Elizabeth Worcester.

    Comments from U.S. Daya Bay Chief Scientist Steve Kettell

    sk
    Steve Kettell

    This body of research is helping to unlock the secrets of the least understood constituents of matter—an important quest considering that neutrinos outnumber all other particle types with a billion neutrinos for every quark or electron.

    The fairly recent discovery that neutrinos have mass changes how we must think about the Standard Model of particle physics because it cannot be explained by that well-accepted description of all known particles and their interactions.

    sm
    The Standard Model of elementary particles, with the three generations of matter, gauge bosons in the fourth column, and the Higgs boson in the fifth.

    Understanding the details of neutrino mass could have huge implications for our understanding of how the universe evolved. And those details—including how neutrinos oscillate, or switch from one flavor to another, are the essence of the research at Daya Bay and a key to unlocking these mysteries.

    The unusual properties of the known neutrinos, particularly their unique mass properties compared to other particles in the Standard Model, give us good reason to suspect that the universe may be full of such neutral particles of other flavors, such as the sterile neutrino. These particles could potentially help account for a large portion of matter in the universe that we cannot detect directly, so called dark matter.

    Daya Bay has been an exciting experiment to work on. It has been exquisitely designed and built, enabling us to make several important discoveries (first result and new result) and to search for these particles. And while the latest study from Daya Bay did not detect evidence of sterile neutrinos, it did greatly narrow the range in which we need to search. We will continue to exploit this beautiful experiment to further explore and understand the properties of the mysterious neutrino.

    The existence of neutrino mass and mixing leads to further deep questions, in particular whether neutrinos are responsible for the dominance of matter over antimatter in the universe. With the first results from Daya Bay this question now seems answerable with the long-baseline neutrino project planned at DOE’s Fermi National Accelerator Laboratory. Brookhaven scientists identified this scientific opportunity and continue to lead the development of this project, which has now been endorsed by recent national advisory panels as the highest priority domestic project in fundamental particle physics.
    See the full article here.

    BNL Campus

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world.Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
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  • richardmitnick 3:10 pm on September 15, 2014 Permalink | Reply
    Tags: , Brookhaven National Labs,   

    From BNL: “Elusive Quantum Transformations Found Near Absolute Zero” 

    Brookhaven Lab

    September 15, 2014
    Justin Eure, (631) 344-2347 or Peter Genzer, (631) 344-3174

    Brookhaven Lab and Stony Brook University researchers measure the quantum fluctuations behind a novel magnetic material’s ultra-cold ferromagnetic phase transition.

    Heat drives classical phase transitions—think solid, liquid, and gas—but much stranger things can happen when the temperature drops. If phase transitions occur at the coldest temperatures imaginable, where quantum mechanics reigns, subtle fluctuations can dramatically transform a material.

    Scientists from the U.S. Department of Energy’s Brookhaven National Laboratory and Stony Brook University have explored this frigid landscape of absolute zero to isolate and probe these quantum phase transitions with unprecedented precision.

    two
    Liusuo Wu, a Stony Brook University Ph.D. student and lead author on the study, with his postdoctoral advisor (and study coauthor) Meigan Aronson, a Brookhaven Lab physicist and Stony Brook professor

    “Under these cold conditions, the electronic, magnetic, and thermodynamic performance of metallic materials is defined by these elusive quantum fluctuations,” said study coauthor Meigan Aronson, a physicist at Brookhaven Lab and professor at Stony Brook. “For the first time, we have a picture of one of the most fundamental electron states without ambient heat obscuring or complicating those properties.”

    The scientists explored the onset of ferromagnetism—the same magnetic polarization exploited in advanced electronic devices, electrical motors, and even refrigerator magnets—in a custom-synthesized iron compound as it approached absolute zero.

    The research provides new methods to identify and understand novel materials with powerful and unexpected properties, including superconductivity—the ability to conduct electricity with perfect efficiency. The study will be published online Sept. 15, 2014, in the journal Proceedings of the National Academy of Sciences.

    “Exposing this quantum phase transition allows us to predict and potentially boost the performance of new materials in practical ways that were previously only theoretical,” said study coauthor and Brookhaven Lab physicist Alexei Tsvelik.

    Mapping Quantum Landscapes

    cry
    Rendering of the near–perfect crystal structure of the yttrium–iron–aluminum compound used in the study. The two–dimensional layers of the material allowed the scientists to isolate the magnetic ordering that emerged near absolute zero.

    The presence of heat complicates or overpowers the so-called quantum critical fluctuations, so the scientists conducted experiments at the lowest possible temperatures.

    “The laws of thermodynamics make absolute zero unreachable, but the quantum phase transitions can actually be observed at nonzero temperatures,” Aronson said. “Even so, in order to deduce the full quantum mechanical nature, we needed to reach temperatures as low as 0.06 Kelvin—much, much colder than liquid helium or even interstellar space.”

    The researchers used a novel compound of yttrium, iron, and aluminum (YFe2Al10), which they discovered while searching for new superconductors. This layered, metallic material sits poised on the threshold of ferromagnetic order, a key and very rare property.

    “Our thermodynamic and magnetic measurements proved that YFe2Al10 becomes ferromagnetic exactly at absolute zero—a sharp contrast to iron, which is ferromagnetic well above room temperature,” Aronson said. “Further, we used magnetic fields to reverse this ferromagnetic order, proving that quantum fluctuations were responsible.”

    The collaboration produced near-perfect samples to prove that material defects could not impact the results. They were also the first group to prepare YFe2Al10 in single-crystal form, which allowed them to show that the emergent magnetism resided within two-dimensional layers.

    “As the ferromagnetism decayed with heat or applied magnetic fields, we used theory to identify the spatial and temporal fluctuations that drove the transition,” Tsvelik said. “That fundamental information provides insight into countless other materials.”

    Quantum Clues to New Materials

    The scientists plan to modify the composition of YFe2Al10 so that it becomes ferromagnetic at nonzero temperatures, opening another window onto the relationship between temperature, quantum transitions, and material performance.

    “Robust magnetic ordering generally blocks superconductivity, but suppressing this state might achieve the exact balance of quantum fluctuations needed to realize unconventional superconductivity,” Tsvelik said. “It is a matter of great experimental and theoretical interest to isolate these competing quantum interactions that favor magnetism in one case and superconductivity on the other.”

    Added Aronson, “Having more examples displaying this zero-temperature interplay of superconductivity and magnetism is crucial as we develop a holistic understanding of how these phenomena are related and how we might ultimately control these properties in new generations of materials.”

    Other authors on this study include Liusuo Wu, Moosung Kim, and Keeseong Park, all of Stony Brook University’s Department of Physics and Astronomy.

    The research was conducted at Brookhaven Lab’s Condensed Matter Physics and Materials Science Department and supported by the U.S. Department of Energy’s Office of Science (BES).

    BNL Campus

    See the full article here.

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world.Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
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  • richardmitnick 9:38 am on August 29, 2014 Permalink | Reply
    Tags: , Brookhaven National Labs, ,   

    From BNL Lab: “DOE ‘Knowledgebase’ Links Biologists, Computer Scientists to Solve Energy, Environmental Issues” 

    Brookhaven Lab

    August 29, 2014
    Rebecca Harrington

    With new tool, biologists don’t have to be programmers to answer big computational questions

    If biologists wanted to determine the likely way a particular gene variant might increase a plant’s yield for producing biofuels, they used to have to track down several databases and cross-reference them using complex computer code. The process would take months, especially if they weren’t familiar with the computer programming necessary to analyze the data.

    ikb
    Combining information about plants, microbes, and the complex biomolecular interactions that take place inside these organisms into a single, integrated “knowledgebase” will greatly enhance scientists’ ability to access and share data, and use it to improve the production of biofuels and other useful products.

    Now they can do the same analysis in a matter of hours, using the Department of Energy’s Systems Biology Knowledgebase (KBase), a new computational platform to help the biological community analyze, store, and share data. Led by scientists at DOE’s Lawrence Berkeley, Argonne, Brookhaven, and Oak Ridge national laboratories, KBase amasses the data available on plants, microbes, microbial communities, and the interactions among them with the aim of improving the environment and energy production. The computational tools, resources, and community networking available will allow researchers to propose and test new hypotheses, predict biological behavior, design new useful functions for organisms, and perform experiments never before possible.

    “Quantitative approaches to biology were significantly developed during the last decade, and for the first time, we are now in a position to construct predictive models of biological organisms,” said computational biologist Sergei Maslov, who is principal investigator (PI) for Brookhaven’s role in the effort and Associate Chief Science Officer for the overall project, which also has partners at a number of leading universities, Cold Spring Harbor Laboratory, the Joint Genome Institute, the Environmental Molecular Sciences Laboratory, and the DOE Bioenergy Centers. “KBase allows research groups to share and analyze data generated by their project, put it into context with data generated by other groups, and ultimately come to a much better quantitative understanding of their results. Biomolecular networks, which are the focus of my own scientific research, play a central role in this generation and propagation of biological knowledge.”

    Maslov said the team is transitioning from the scientific pilot phase into the production phase and will gradually expand from the limited functionality available now. By signing up for an account, scientists can access the data and tools free of charge, opening the doors to faster research and deeper collaboration.
    Easy coding

    “We implement all the standard tools to operate on this kind of key data so a single PI doesn’t need to go through the hassle by themselves.”
    — Shinjae Yoo, assistant computational scientist working on the project at Brookhaven

    As problems in energy, biology, and the environment get bigger, the data needed to solve them becomes more complex, driving researchers to use more powerful tools to parse through and analyze this big data. Biologists across the country and around the world generate massive amounts of data — on different genes, their natural and synthetic variations, proteins they encode, and their interactions within molecular networks — yet these results often don’t leave the lab where they originated.

    “By doing small-scale experiments, scientists cannot get the system-level understanding of biological organisms relevant to the DOE mission,” said Shinjae Yoo, an assistant computational scientist working on the project at Brookhaven. “But they can use KBase for the analysis of their large-scale data. KBase will also allow them to compare and contrast their data with other key datasets generated by projects funded by the DOE and other agencies. We implement all the standard tools to operate on this kind of key data so a single PI doesn’t need to go through the hassle by themselves.”

    For non-programmers, KBase offers a “Narrative Interface,” allowing them to upload their data to KBase and construct a narrative of their analysis with a series of pre-coded programs that has a human in the middle interpreting and filtering their output.

    In one pre-coded narrative, researchers can filter through naturally occurring variations of Poplar genes, one of the DOE flagship bioenergy plant species. Scientists can discover genes associated with a reduced amount of lignin—a cell wall protein that makes conversion of Poplar biomass to biofuels more difficult. In this narrative, scientists can use datasets from KBase and from their own research to then find candidate genes, and use networks to select the genes most likely to be related to a specific trait they’re looking for—say, genes that result in reduced lignin content, which could ease the biomass to biofuel conversion. And if other researchers wanted to run the same program for a different plant, they could just put different data in the same narrative.

    “Everything is already there,” Yoo said. “You simply need to upload the data in the right format and run through several easy steps within the narrative.”

    For those who know how to code, KBase has the IRIS Interface, a web-based command line terminal where researchers can run and control the programs on their own, allowing scientists to analyze large volumes of data. If researchers want to learn how to do the coding themselves, KBase also has tutorials and resources to help interested scientists learn it.
    A social network

    But KBase’s most powerful resource is the community itself. Researchers are encouraged to upload their data and programs so that other users can benefit from them. This type of cooperative environment encourages sharing and feedback among researchers, so the programs, tools, and annotation of datasets can improve with other users’ input.

    Brookhaven is leading the plant team on the project, while the microbe and microbial community teams are based at other partner institutions. A computer scientist by training, Yoo said his favorite part of working on KBase has been how much biology he’s learned. Acting as a go-between among the biologists at Brookhaven, who are describing what they’d like to see KBase be able to do, and the computer scientists, who are coding the programs to make it happen, Yoo has had to understand both languages of science.

    “I’m learning plant biology. That’s pretty cool to me,” he said. “In the beginning, it was quite tough. Three years later I’ve caught up, but I still have a lot to learn.”

    Ultimately, KBase aims to interweave huge amounts of data with the right tools and user interface to enable bench scientists without programming backgrounds to answer the kinds of complex questions needed to solve the energy and environmental issues of our time.

    “We can gain systematic understanding of a biological process much faster, and also have a much deeper understanding,” Yoo said, “so we can engineer plant organisms or bacteria to improve productivity, biomass yield—and then use that information for biodesign.”

    KBase is funded by the DOE’s Office of Science. The Office of Science (SC) is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.

    See the full article here.

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world.Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
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  • richardmitnick 10:49 am on August 18, 2014 Permalink | Reply
    Tags: , Brookhaven National Labs, Ferroelectrics   

    From Brookhaven Lab: “Promising Ferroelectric Materials Suffer From Unexpected Electric Polarizations” 

    Brookhaven Lab

    August 18, 2014
    Justin Eure, (631) 344-2347 or Peter Genzer, (631) 344-3174

    Brookhaven Lab scientists find surprising locked charge polarizations that impede performance in next-gen materials that could otherwise revolutionize data-driven devices.

    Electronic devices with unprecedented efficiency and data storage may someday run on ferroelectrics—remarkable materials that use built-in electric polarizations to read and write digital information, outperforming the magnets inside most popular data-driven technology. But ferroelectrics must first overcome a few key stumbling blocks, including a curious habit of “forgetting” stored data.

    three
    Scientists and study coauthors from Brookhaven Lab’s Condensed Matter Physics and Materials Science Department stand beside a transmission electron microscope (TEM) capable of capturing nanoscale structures. From left: Myung-Geun Han, Yimei Zhu, and Lijun Wu.

    “For the first time, we could see these unusual and jagged polarizations mapped out in real space and real time.”
    — Brookhaven Lab scientist and study coauthor Myung-Geun Han

    Now, scientists at the U.S. Department of Energy’s Brookhaven National Laboratory have discovered nanoscale asymmetries and charge preferences hidden within ferroelectrics that may explain their operational limits.

    “The positive or negative polarizations in these ferroelectric materials should be incredibly easy to switch, but the reality is much stranger,” said Brookhaven Lab physicist Myung-Geun Han, lead author on the new study. “To our surprise, opposing electronic configurations only allowed for polarization in one direction—a non-starter for reading and writing data.”

    The researchers used a suite of state-of-the-art techniques—including real-time electrical biasing, electron holography, and electron-beam-induced current measurements—to reveal never-before-seen electric field distributions in ferroelectric thin films, which were custom-grown at Yale University. The results, published in Nature Communications, open new pathways for ferroelectric technology.

    Physics of Flipping

    land
    electrostatic potential landscapes

    Electrostatic potential landscapes reconstructed from electron holography data with 15 volts of positive or negative current applied to the substrate (Nb-STO). The much steeper potential drop from the +15 V signifies a higher electric field, whereas the -15 V yielded a much flatter curve—indicating the charge asymmetry within the material.

    Most electronic devices rely on ferromagnetism to read and write data. Each so-called ferromagnetic domain contains a north or south magnetic polarity, which translates into the flipping 1 or 0 of the binary code underlying all digital information. But ferromagnetic operations not only require large electric current, but the magnets can flip each other like dominoes when packed together too tightly—effectively erasing any data.

    Ferroelectrics, however, use positive or negative electric charge to render digital code. Crucially, they can be packed together with domains spanning just a few atoms and require only a tiny voltage kick to flip the charge, storing much more information with much greater efficiency.

    “But ferroelectric commercialization is held up by material fatigue, sudden polarization reversal, and intrinsic charge preferences,” said Brookhaven Lab physicist and study coauthor Yimei Zhu. “We suspected that the origin of these issues was in the atomic interactions along the material’s interface—where the ferroelectric thin film sits on a substrate.”

    Interface Exploration
    switch
    These dark-field transmission electron microscopy (TEM) images show ferroelectric domain switching under various external biases. Without external current, the PZT film is split—the two opposing polarization are arranged in a head-to-head configuration. Crucially, with –10 V applied in the bottom image, the domains near the PZT/Nb-STO interface fail to switch.

    The scientists examined ferroelectric films of lead, zirconium, and titanium oxide grown on conductive substrates of strontium, and titanium oxide with a small amount of niobium—chosen because it exhibits large polarization values with well-defined directions, either up or down. The challenge was mapping the internal electric fields in materials thousands of times thinner than a human hair under actual operating conditions.

    Brookhaven scientists hunted down the suspected interface quirks using electron holography. In this technique, a transmission electron microscope (TEM) fired 200,000-volt electron wave packets through the sample with billionth-of-a-meter precision. Negative and positive electric fields inside the ferroelectric film then attracted or repelled the electron wave and slightly changed its direction. Tracking the way the beam bent throughout the ferroelectric film revealed its hidden charges.

    “Rather than an evenly distributed electric field, the bending electron waves revealed non-uniform and unidirectional electric fields that induced unstable, head-to-head domain configurations,” Han said. “For the first time, we could see these unusual and jagged polarizations mapped out in real space and real time.”

    These opposing polarizations—like rival football teams squaring off aggressively at the line of scrimmage—surprised scientists and challenged assumptions about the ferroelectric phenomenon.

    “These results were totally unexpected based on the present understanding of ferroelectrics,” Han said.

    The asymmetries were further confirmed by measurements of electron-beam-induced current. When a focused electron beam struck the ferroelectric sample, electric fields within the film-substrate interface revealed themselves by generating additional current. Other techniques, including piezoresponse force microscopy—in which a sub-nanometer tip induces a reaction by pressing against the ferroelectric—also confirmed the strange domains.

    “Each technique demonstrated this intrinsic polarization preference, likely the origin of the back-switching and poor coding performance in these ferroelectrics,” Han said. “But these domain structures should require a lot of energy and thus be very unstable. The interface effect alone cannot explain their existence.”
    Missing Oxygen

    The scientists used another ultra-precise technique to probe the material’s interface: electron energy loss spectroscopy (EELS). By measuring the energy deposited by an electron beam in specific locations—a kind of electronic fingerprint—the scientists determined the material’s chemical composition.

    “We suspect that more oxygen could be missing near the surface of the thin films, creating electron pockets that may neutralize positive charges at the domain walls,” Han said. “This oxygen deficiency naturally forms in the material, and it could explain the stabilization of head-to-head domains.”

    This electron-swapping oxygen deficiency—and its negative effects on reliably storing data—might be corrected by additional engineering, Han said. For example, incorporating a “sacrificial layer” between the ferroelectric and the substrate could help block the interface interactions. In fact, the study may inspire new ferroelectrics that either exploit or overcome this unexpected charge phenomenon.

    Other authors include Lijun Wu and Marvin A. Schofield of Brookhaven Lab; Matthew S. J. Marshall, Jason Hoffman, Frederick J. Walker, and Charles H. Ahn of the Yale University Department of Applied Physics and Center for Research on Interfaces Structures and Phenomena; Toshihiro Aoki of JEOL USA Inc.; and Ray Twesten of Gatan Inc.

    The samples used for transmission electron microscopy (TEM) were prepared by Kim Kisslinger at Brookhaven Lab’s Center for Functional Nanomaterials, a U.S. Department of Energy user facility.

    The research was supported by the U.S. Department of Energy’s Office of Science.

    See the full article here.

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world.Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
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  • richardmitnick 9:09 am on August 15, 2014 Permalink | Reply
    Tags: , Brookhaven National Labs, Condensed Matter Physics,   

    From Brookhaven Lab: “New Grant to Aid Search for the Secrets of Superconductivity” 

    Brookhaven Lab

    August 12, 2014
    Karen McNulty Walsh

    Research aimed at unlocking the secrets of high-temperature superconductivity at the U.S. Department of Energy’s Brookhaven National Laboratory will get a boost from a new grant awarded to Ivan Bozovic, a Brookhaven physicist and an Adjunct Professor at Yale University, by the Gordon and Betty Moore Foundation. Bozovic will receive $1.9 million over five years as part of the Moore Materials Synthesis Investigators program to continue the meticulous assembly and manipulation of superconducting thin films and the exploration of factors underlying these remarkable materials’ ability to carry electric current with no energy loss.

    “I am very grateful for this grant, which recognizes the importance of methodical work that slowly but steadily improves materials synthesis techniques and sample quality,” Bozovic said. Such quality is essential to uncover subtle effects in high-temperature superconductors, which, Bozovic notes, can be masked by impurities. “The better the samples, the more precise and revealing our experiments can be — and the greater their potential for new insights and discoveries,” he said.

    To achieve such precision, Bozovic uses a one-of-a-kind molecular-beam epitaxy (MBE) machine that he built and continues to improve to fabricate superconducting thin films one atomic layer at a time. He and collaborators have used the machine to assemble more than 2,000 thin film samples and conduct hundreds of scientific experiments. He also contributes to research at Brookhaven’s Center for Emergent Superconductivity, one of DOE’s Energy Frontier Research Centers, which recently received renewed funding.

    “I am very grateful for this grant, which recognizes the importance of methodical work that slowly but steadily improves materials synthesis techniques and sample quality.”
    — Brookhaven physicist Ivan Bozovic

    ib

    Leveraging his atomic-layer-by-layer synthesis technique, Bozovic made a series of discoveries related to interface superconductivity, bringing it to the forefront of research in Condensed Matter Physics. He showed that superfluid can be confined to a single atomic layer at the interface of two materials, neither of which is superconducting. In another important experiment, he proved that electron pairs exist on both sides of the superconductor-to-insulator transition an important insight into the mysterious nature of the high-temperature superconductivity phenomenon.

    Bozovic is one of only 12 scientists to be awarded funding through the Moore Materials Synthesis Investigators program, part of the foundation’s Emerging Phenomena in Quantum Systems (EPiQS) initiative. Quantum materials, the Foundation notes, are substances in which the collective behavior of electrons leads to many complex and unexpected emergent phenomena, superconductivity being a prominent example.

    In announcing the grantees, the Foundation stated:

    “Our approach is to focus on some of the field’s leading scientists; to allow these scientists the freedom to explore and the flexibility to change research directions; and to incentivize sample sharing within the EPiQS program and beyond…We believe that our programs will lead to discoveries of new quantum materials with emergent electronic properties as well as an increase in the availability of top-quality samples to the experimental community.”

    Bozovic earned a Ph.D. in physics from the University of Belgrade in Yugoslavia in 1975. He remained there until 1985 and served as a professor and the Head of the Physics Department. From 1986 until 1988, he worked at the Applied Physics Department at Stanford University. He was a senior research scientist at Varian Research Center in Palo Alto, California, 1989 to 1998, and the chief technical officer and principal scientist for Oxxel GmbH in Germany 1998 to 2002. He joined Brookhaven as a senior scientist and the leader of the Molecular Beam Epitaxy group in 2003. In 2012 he was a co-recipient of the Bernd T. Matthias Prize for Superconducting Materials, and in 2013 was chosen to give the Max Planck Lecture at MPI-Stuttgart, Germany. His research results have been published in more than 200 research papers and cited more than 6,500 times. Many of these were published in the highest-impact journals such as Nature, Science, and Nature Materials. Bozovic is a Fellow of APS and of SPIE, and a Foreign Member of Serbian Academy of Science and Arts.

    Bozovic’s research at Brookhaven is supported by the DOE Office of Science. The Moore Foundation grant will be awarded to him by way of his adjunct appointment at Yale University.

    See the full article here.

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world.Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
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  • richardmitnick 8:39 am on August 11, 2014 Permalink | Reply
    Tags: , Brookhaven National Labs, ,   

    From Brookhaven Lab: “Dark Interactions Workshop Brings Global Physicists to Brookhaven” 

    Brookhaven Lab

    August 11, 2014
    Chelsea Whyte

    people
    Nearly 80 physicists — representing experiments from laboratories including Thomas Jefferson National Accelrator Facility, the Large Hadron Collider, the Mainz Microtron, SLAC National Accelerator Laboratory, KEK, and universities involved in other dark particle detector experiments — attended the Dark Interactions Workshop at Brookhaven National Laboratory in June 2014.

    For three days in June, physicists from around the world came together at the U.S. Department of Energy’s Brookhaven National Laboratory for the inaugural physics workshop “Dark Interactions: Perspectives from Theory and Experiment,” chaired by Brookhaven physicist Ketevi Assamagan. He jointly organized the workshop with Brookhaven physicist Hooman Davoudiasl and Stony Brook University assistant professor of physics Rouven Essig.

    The goal of the workshop was to review and discuss the theoretical context as well as the status and future of the searches for dark sector particles, such as dark vector bosons, and the implications for dark matter.

    “We hope to continue this meeting in the years to come. We gain a lot by sharing ideas between theorists and experimentalists,” Assamagan said. Nearly 80 physicists attended the workshop to hear presentations that covered a range of topics on the frontier of new physics: the theories and experiments trying to track down dark matter, the mysterious substance that neither emits nor absorbs light, but is theorized to comprise nearly 27% of the cosmos.

    So far, despite the tremendous amount of evidence for the existence of dark matter, nobody knows its identity; but if anyone is going to devise a way to determine its makeup, it could be one of the physicists in attendance at the workshop. Over the course of several days, they discussed theoretical motivations for the search for dark matter, and several experiments already looking for the mystery matter, including:

    The DarkLight, HPS, and APEX experiments at Thomas Jefferson National Accelerator Facility;
    The CMS, ATLAS, ALICE and LHCb experiments at the Large Hadron Collider in Geneva, Switzerland;
    The A1 collaboration at the Mainz Microtron;
    Dark photon and low-mass Higgs searches at the BaBar detector at the SLAC National Accelerator Laboratory;
    The Belle Collaboration at KEK
    The PHENIX experiment at Brookhaven National Laboratory
    The Muon g-2 experiment [at Fermilab]
    The Axion Dark Matter Experiment at the University of Washington
    LHC experiments, namely ATLAS, CMS, ALICE and LHCb also contribute to the searches for Dark Matter. Ketevi Assamagan (BNL) and Oliver Keith Baker (Yale University) are working on some of the ATLAS analyses that may provide clues into the nature of Dark Matter.

    “It’s hard to believe dark matter is an idea that’s 80 years old,” said Professor David Brown of the University of Louisville. “Of course, we still don’t know what dark matter is. But colliders let us search for dark particles.”

    “Understanding the nature of dark matter poses one of the most urgent problems for our fundamental description of the Universe,” Davoudiasl said. “Interactive meetings, like DI2014, allow us to share various points of view on the scope of theoretical and experimental opportunities, as well as challenges, that lie ahead in the quest to uncover the properties of dark matter.”

    The attendees shared results from experiments all over the world, with tantalizing hints at the nature of dark matter. And as they continue this search, coordination across disciplines and national borders remains key to collaboration.

    “An enormous amount of progress has been made over the last few years in the search for dark matter and dark forces,” Essig said. “All of us hope that the current generation of experiments will be successful at finding new physics.”

    See the full article here.

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