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  • richardmitnick 12:04 pm on November 19, 2013 Permalink | Reply
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    From Brookhaven Lab: “Infrared Light Fills a ‘Gap’ in Iron-based Superconductor Research” 

    Brookhaven Lab

    November 18, 2013
    Laura Mgrdichian

    Superconductors are a fascinating group of materials in which electrons can flow with almost zero resistance. They have the potential to revolutionize electronics and power distribution, but no existing superconductors have an ideal combination of properties necessary to realize these applications. To design the ideal superconductor, scientists need a complete understanding of the complex, atomic-level electrical and magnetic behaviors that produce the phenomenon.

    Many groups have focused their efforts on “high-temperature” (high-Tc) superconductors that operate at temperatures well above the conventional superconducting materials. Conventional superconductors must be chilled to almost absolute zero (the coldest temperature possible), making them impractical for many applications. The most widely studied high-Tc materials, known as cuprates because they contain layers of copper and oxygen atoms, avoid the ultra-low temperature requirement, but exhibit other properties that limit their practical use.

    Recently, a new family of iron-based superconductors was discovered that do not seem to superconduct in the same way as conventional superconductors or quite like the cuprates. This iron-based family has been found to be quite large and diverse, so physicists are hoping that studying all of its members will yield a clear picture of how they operate, and point the way to a high-Tc material that has other necessary properties.

    graph
    (a) Data taken from 3 to 30K showing the temperature dependence of infrared transmission through the LaFeAsO1-‐xFx thin film, normalized to the transmission at 33K (b) Time-‐resolved infrared transmission data through the sample from about 2K to 15K. The slow (ns) relaxation time indicates the presence of a full superconducting gap.

    In this work, researchers from Brookhaven National Laboratory and the Leibniz Institute for Solid State Physics in Dresden, Germany, investigated an iron pnictide compound composed of lanthanum (La), iron (Fe), arsenic (As), oxygen (O), and an added fluorine (F) “dopant” that replaces about 10 percent of the O atoms. Abbreviated LaFeAsO1-xFx (the ‘x’ denotes the number of F and, therefore, O atoms per molecule), it was the first iron-based superconductor found to operate at temperatures higher than most conventional superconductors. Still, little is known about how it works.

    This work may be a key step in changing that. Using beams of infrared light produced at Brookhaven’s National Synchrotron Light Source, the group discovered evidence that LaFeAsO1-xFx has a full “superconducting gap” – the energy required for electrons in the lowest energy state, the ground state, to “jump” into higher energy levels. This gap is one hallmark of a superconductor and an indicator of its performance under certain conditions. For example, the gap in the cuprates actually disappears for electrons traveling in certain directions.

    “Understanding the details of the gap is essential for unraveling the superconducting mechanism, yet questions about gap structure in this material have persisted even after years of research,” said Brookhaven researcher Xiaoxiang Xi, who was the lead experimenter in the study. “Establishing these details experimentally, as we have done, puts constraints on the possible theories that could explain the origin of the superconductivity in these materials.”

    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 11:03 am on November 15, 2013 Permalink | Reply
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    From Brookhaven Lab: “Small Particles, Big Findings” 

    Brookhaven Lab

    November 15, 2013
    Karen McNulty Walsh

    Sometimes big change comes from small beginnings. That’s especially true in the research of Anatoly Frenkel, a professor of physics at Yeshiva University, who is working to reinvent the way we use and produce energy by unlocking the potential of some of the world’s tiniest structures: nanoparticles.

    “The nanoparticle is the smallest unit in most novel materials, and all of its properties are linked in one way or another to its structure,” said Frenkel. “If we can understand that connection, we can derive much more information about how it can be used for catalysis, energy, and other purposes.”

    three
    Eric Stach and Dmitri Zakharov of the CFN with Anatoly Frenkel of Yeshiva University and his postdoc, Yuanyuan Li, sitting at the Titan 80/300 Environmental Transmission Electron Microscope at the CFN.

    “This work could lead to big gains in energy efficiency and cost savings for industrial processes.” — Eric Stach, CFN

    Frenkel is collaborating with materials scientist Eric Stach and others at the U.S. Department of Energy’s Brookhaven National Laboratory to develop new ways to study how nanoparticles behave in catalysts—the “kick-starters” of chemical reactions that convert fuels to useable forms of energy and transform raw materials to industrial products.

    “We are developing a new ‘micro-reactor’ that enables us to explore many aspects of catalytic function using multiple approaches at Brookhaven’s National Synchrotron Light Source (NSLS), the soon-to-be-completed NSLS-II, and the Center for Functional Nanomaterials (CFN),” said Stach, who works at the CFN. “This approach lets us understand multiple aspects of how catalysts work so that we can tweak their design to improve their function. This work could lead to big gains in energy efficiency and cost savings for industrial processes.”

    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 9:41 am on November 7, 2013 Permalink | Reply
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    From Brookhaven Lab: “New Camera Reveals How Light Breaks Molecules Apart” 

    Brookhaven Lab

    November 4, 2013
    Andrei Nomerotski and Michael White

    Way beyond pure illumination—from bright sunshine to intense x-rays at the National Synchrotron Light Source (NSLS)—light can pack a powerful punch down at the atomic scale. When light strikes organic compounds bound to certain surfaces, it can split them into atomic and molecular fragments called photoproducts. These fractured pieces offer crucial clues to how and why light breaks some chemical bonds, which is at the core of understanding how solar energy can be used to remove pollutants from the environment.

    Just one organic molecule can break into many photoproducts and capturing each one presents a considerable, time-consuming challenge. We used a highly specialized system—the Pixel Imaging Mass Spectrometry (PImMS) camera—to bring this light-induced process into focus. Results of our experiments using the new PImMS camera to capture these telltale photoproducts were just published in the Journal of Chemical Physics and highlighted in Physics Today. With PImMS performing beautifully, the technology could also be used in research at NSLS-II and the proposed electron-ion collider, eRHIC.

    camera
    From left: Physicist Andrei Nomerotski, Stony Brook University graduate student Matt Kershis, and chemist Michael White use this instrument to prepare organic molecule samples for tests with the new PImMS camera.

    Tracking Photoproducts, Pre-PImMS

    Several years ago, Michael and his colleagues in the Chemistry Department began exploring how ultraviolet (UV) light can cause organic molecules on titanium dioxide surfaces to decompose into photoproducts. This important reaction, called photo-oxidation, removes organic pollutants from air and water and is the basis for windows and building exteriors’ self-cleaning coatings.

    Before PImMS, we used a technique called ion imaging and a conventional imaging camera—with a charge-coupled device (CCD) sensor similar to those in consumer cameras—to track photoproducts that struck a two-dimensional detector. But in this method, each of these many photoproducts must be captured as individual images, requiring multiple sample preparations and time-consuming repetition. We needed a better camera to catch all the action.

    Enter the PImMS Camera

    Fortunately, an Oxford University group—including Andrei, who only recently joined Brookhaven’s Physics Department to work on the Large Synoptic Survey Telescope—developed a new camera capable of conventional imaging while simultaneously measuring the arrival time for each photoproduct that strikes the detector. This information acts much like a photographic time stamp and could essentially reveal all the photoproducts with a single image exposure.

    Now, instead of repeatedly capturing and reading out whole frames, one after another, PImMS records up to four ion arrival times inside each pixel, a bit like multiple exposures on a film camera. We then read out the sensor just once at the very end of the experimental cycle to gather all that information, accelerating the entire process. In fact, the PImMS camera has an effective imaging speed of just 10 nanoseconds—that’s 100,000 times faster than a conventional CCD camera—and experimental cycles can now take 25 percent of the time they used to. The new sensor combines time-of-flight mass spectrometry to identify multiple molecules, and sensitive ion imaging, which revolutionized the field of chemical reaction dynamics.

    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 9:07 pm on September 18, 2013 Permalink | Reply
    Tags: , Brookhaven CFN, , Brookhaven NSLS, , ,   

    From Brookhaven Lab: “Nanocrystal Catalyst Transforms Impure Hydrogen into Electricity” 

    Brookhaven Lab

    Brookhaven Lab scientists use simple, ‘green’ process to create novel core-shell catalyst that tolerates carbon monoxide in fuel cells and opens new, inexpensive pathways for zero-emission vehicles

    September 18, 2013
    Contacts: Justin Eure, (631) 344-2347 or Peter Genzer, (631) 344-3174

    The quest to harness hydrogen as the clean-burning fuel of the future demands the perfect catalysts—nanoscale machines that enhance chemical reactions. Scientists must tweak atomic structures to achieve an optimum balance of reactivity, durability, and industrial-scale synthesis. In an emerging catalysis frontier, scientists also seek nanoparticles tolerant to carbon monoxide, a poisoning impurity in hydrogen derived from natural gas. This impure fuel—40 percent less expensive than the pure hydrogen produced from water—remains largely untapped.

    “Our highly scalable, ‘green’ synthesis method, as revealed by atomic-scale imaging techniques, opens new and exciting possibilities for catalysis and sustainability.”
    — Brookhaven Lab Chemist Jia Wang

    team
    Brookhaven Lab scientists Radoslav Adzic, Vyacheslov Volcov, Lijun Wu (back), Wei An, Jia Wang, and Dong Su (front) gathered in the control room for a scanning transmission electron microscope (STEM) in the Center for Functional Nanomaterials.

    Now, scientists at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory—in research published online September 18, 2013 in the journal Nature Communications—have created a high-performing nanocatalyst that meets all these demands. The novel core-shell structure—ruthenium coated with platinum—resists damage from carbon monoxide as it drives the energetic reactions central to electric vehicle fuel cells and similar technologies.

    “These nanoparticles exhibit perfect atomic ordering in both the ruthenium and platinum, overcoming structural defects that previously crippled carbon monoxide-tolerant catalysts,” said study coauthor and Brookhaven Lab chemist Jia Wang. “Our highly scalable, ‘green’ synthesis method, as revealed by atomic-scale imaging techniques, opens new and exciting possibilities for catalysis and sustainability.”

    Scientists at Brookhaven Lab’s National Synchrotron Light Source (NSLS) revealed the atomic density, distribution, and uniformity of the metals in the nanocatalysts using a technique called x-ray diffraction, where high-frequency light scatters and bends after interacting with individual atoms. The collaboration also used a scanning transmission electron microscope (STEM) at Brookhaven’s Center for Functional Nanomaterials (CFN) to pinpoint the different sub-nanometer atomic patterns. With this instrument, a focused beam of electrons bombarded the particles, creating a map of both the core and shell structures.

    “We found that the elements did not mix at the core-shell boundary, which is a critical stride,” said CFN physicist Dong Su, coauthor and STEM specialist. “The atomic ordering in each element, coupled with the right theoretical models, tells us about how and why the new nanocatalyst works its magic.”

    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 7:06 am on September 6, 2013 Permalink | Reply
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    From Brookhaven Lab: “Molecular Structure Reveals How the Antibiotic Streptomycin Works” 

    Brookhaven Lab

    September 5, 2013
    Laura Mgrdichian

    Streptomycin was the first antibiotic developed to treat tuberculosis yet until recently, scientists did not completely understand how it works at the molecular level. They knew that streptomycin blocks a critical process, the synthesis of proteins by ribosomes leading to bacterial cell death, but certain details of the interaction remained undiscovered. At Brookhaven National Laboratory’s National Synchrotron Light Source, researchers have used x-ray crystallography to complete the picture.

    strep
    A) A ribbon diagram of the ribosome’s streptomycin binding site. B) A close-up of the rectangular area outlined in A. Streptomycin Is represented as yellow sHcks and spheres, helices are colored red, dark green, cyan, orange, and blue.

    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 2:21 pm on August 23, 2013 Permalink | Reply
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    From Brookhaven Lab: "Mastering Microbunching for Linac-based Light Sources" 

    Brookhaven Lab

    August 19, 2013
    Boris Podobedov, Sergei Seletskiy, and Xi Yang

    “Designing accelerators requires years of research and development. Throughout the Lab’s history, scientists and engineers at Brookhaven have helped lead the way in designing accelerator technologies for cutting-edge facilities here on site and at institutions around the world.

    Our team in the Photon Sciences Directorate and Yuzhen Shen, who is now with the U.S. Patent and Trademark Office, recently tackled a significant problem in accelerator design, a phenomenon called microbunching instability that has been identified as one of the most serious challenges to the performance of advanced linear accelerator (linac)-based light sources.

    three
    Brookhaven Lab accelerator physicists (from left) Xi Yang, Sergei Seletskiy, and Boris Podobedov

    Light sources, including the National Synchrotron Light Source (NSLS) and the future NSLS-II at Brookhaven, are important tools for producing ultra-bright light that scientists can use to analyze the atomic and molecular structures for advances in different areas of science, ranging from biology and physics to chemistry and geophysics, as well as medicine and materials science. Some light sources are linac-based and others, such as NSLS and NSLS-II, are based on storage rings. In both kinds, the bright light—large quantities of photons—is produced from electron beams that travel in bunches through certain accelerator components, for instance bending magnets or undulators.

    Electrons are never distributed completely evenly inside a bunch and any small ‘noise’ in an unstable bunch can cause the electrons to form microstructures as they clump closer or spread further apart. This effect, the microbunching instability, results in chaotic changes of beam density distribution. In extreme cases, especially for more intense bunches that provide higher brightness at light sources, bunches simply split apart. This effect degrades the quality of electron beams and the photon beams they produce.

    The microbunching instability is rather common and especially important in the fourth generation light sources, such as the Linear Coherent Light Source at SLAC National Accelerator Laboratory in California. They rely on short-wavelength free electron lasers (FELs) that use short, dense bunches of electrons traveling at nearly the speed of light to make short photon bunches.

    Recently, a lot of research has been completed to address the microbunching instability, but thorough understanding had not been achieved, mainly because experimental data was scarce and inconclusive. This isn’t surprising. Noise is impossible to control, so any phenomenon that initiates from it is hard to study experimentally. Measurable effects such as the final shape of an electron bunch could vary wildly from one bunch to the next.

    Microbunching for Our Benefit

    An electron bunch, as seen on the spectrometer screen. By controlling the microbunching instability, this bunch is completely split into about 10 sub–bunches spaced 25 micrometers apart. The ability to control the number of sub-bunches, the distance between them, and their intensity could be beneficial for a number of light sources.

    In our recent work, performed at the NSLS Source Development Laboratory photoinjected linac, we used a novel technique to overcome this challenge. By pre-shaping the electron clumps inside a bunch in a controlled fashion, we were able to ‘seed’ the instability and then study how it developed. With this technique, we were able to—for the first time—systematically characterize the microbunching instability and validate important theoretical predictions. Furthermore, our results suggested approaches for designing an accelerator that suppresses this instability, even for very intense bunches in which the effect is more likely to degrade the quality of both electron beams and the light they emit.

    Perhaps even more interesting, we showed that modern linac-based light sources could actually benefit from microbunching instability. This is something the accelerator physics community has contemplated, but it wasn’t demonstrated until now.”

    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 1:38 pm on July 2, 2013 Permalink | Reply
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    From Brookhaven Lab: “Scientists Identify Promising Antiviral Compounds” 

    Brookhaven Lab

    Structural details and computational modeling may lead to rational design of drugs to combat adenovirus

    July 2, 2013
    Contacts: Karen McNulty Walsh, (631) 344-8350 or Peter Genzer, (631) 344-3174printer iconPrint

    “Scientists at the U.S. Department of Energy’s Brookhaven National Laboratory have identified two promising candidates for the development of drugs against human adenovirus, a cause of ailments ranging from colds to gastrointestinal disorders to pink eye. A paper published in FEBS Letters, a journal of the Federation of European Biochemical Societies, describes how the researchers sifted through thousands of compounds to determine which might block the effects of a key viral enzyme they had previously studied in atomic-level detail.

    mn
    Brookhaven biophysicist Walter Mangel. No image credit.

    ‘This research is a great example of the potential for rational drug design,’ said lead author Walter Mangel, a biologist at Brookhaven Lab. ‘Based on studies of the atomic-level structure of an enzyme that’s essential for the maturation of adenovirus and how that enzyme becomes active—conducted at Brookhaven’s National Synchrotron Light Source (NSLS)—we used computational modeling to search for compounds that might interfere with this enzyme and tested the best candidates in the lab.’

    virus
    Structures of the adenovirus proteinase in inactive form (turquoise) and activated (yellow) by binding of a co-factor (beige), in association with a promising inhibitor compound identified in this research (circular “ball and stick” molecule). In the inactive form, left, the inhibitor blocks the “pocket” into which the co-factor binds, thus preventing the enzyme from becoming active. In the fully activated enzyme, right, the inhibitor binds in the now-exposed protein-cleaving “active site,” thus blocking the enzyme’s protein-cleaving ability. The fact that this inhibitor works to disable the proteinase in two different ways at two different sites increases the chance that drugs based on this compound will be successful at fighting adenovirus infection. It also makes it less likely that adenovirus will develop resistance to such drugs.

    Out of 140,000 compounds in a national database, the scientists identified two they expect to be able to turn into antiviral agents to combat adenovirus.”

    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. 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 4:14 pm on June 21, 2013 Permalink | Reply
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    From Brookhaven Lab: “Extreme Insulating-to-conducting Nanowires Promise Novel Applications” 

    Brookhaven Lab

    June 21, 2013
    Laura Mgrdichian

    “Scientists are just beginning to discover and investigate materials that can change from insulators to conductors at room temperature under an applied voltage. There are only a few known examples, but their potential for use in new technologies – as futuristic as the ‘invisibility cloak’ donned by Harry Potter in the book series by the same name – is very exciting.

    nano
    Scanning transmission image of synthesized crystalline nanowires. No image credit.

    At NSLS, researchers have studied a new addition to this elite group – nanowires made of vanadium oxide bronze – and measured drastic, never-before-seen transitions from insulator to conductor. Their work also hints at what happens at the atomic-level. This is a crucial step toward developing possible applications, which include a type of computer memory known as a memristor, now in development at some companies; new varieties of electrochromic coatings, thin films that reversibly change color in response to an applied voltage; and transistors.

    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 12:57 pm on April 18, 2013 Permalink | Reply
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    From Brookhaven Lab: “Temperature-dependent Radiolysis Reveals Dynamics of Bound Protein Waters” 

    Brookhaven Lab

    April 18, 2013
    Chelsea Whyte

    “Water is crucial to the functioning of the body, even on very small scales. The ubiquitous liquid is key to the structure, folding and stability of proteins, but one of the still unanswered questions in the study of the structure and function of proteins and DNA is their exact relationship to their water environment. All of the molecules in our bodies function in water, but until now, we haven’t had a lot of experimental techniques to understand what water is doing or where it is binding to the interior surfaces of proteins.

    water
    Cyt c 18O-labeling map. The sites of 18O-modifications are visualized from the crystal structure 1HRC (27) using PyMOL. The 18O-labeled residues (light blue) in and around the heme (light pink) crevices, and the position of residue T78 (gray) and conserved waters (cyan spheres) HOH112, HOH139 are shown in two orientations of the cyt c molecule.

    A team of scientists from Case Western Reserve University used the National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory to develop a technique that pinpoints the location and motion of water molecules bound to proteins. Using temperature-dependent radiolysis and mass spectroscopy, they are able to identify where water is binding tightly or loosely on the surface of a protein and how it is influencing a protein’s function.

    ‘It’s as if there were a window ledge with a pebble stuck in it, so the window doesn’t shut tightly,’ said Mark Chance, director of the Center for Proteomics and Bioinformatics at Case Western University. ‘The water is like that pebble. It could be an obstacle to the formation of the protein complex, just like the pebble stops the window closing. Or, it could be in just the right position, as if the window had a small notch carved in just the shape of the pebble. Both of those situations could occur in nature.’”

    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. 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 2:55 pm on April 9, 2013 Permalink | Reply
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    From Brookhaven Lab: “Structure Helps Yield Drug ‘Hypersensitivity’ Tests for Patients” 

    Brookhaven Lab

    April 8, 2013
    Laura Mgrdichian

    “From a patient’s point of view, one of the unsettling things about taking a new drug is the possibility of unwelcome side effects or worse, dangerous allergic reactions. As drugs are being developed and then enter clinical trials, these issues play a huge role in the process, increasing costs and sometimes determining whether a drug will get to market at all.

    drug
    In this “ribbon diagram,” the HIV/AIDS drug abacavir (orange, blue and red spheres) interacts with a protein (grey) made by a particular gene that causes a hypersensitivity to the drug. The protein “shows” the body’s immune system a peptide (light blue) it has never seen, causing an allergic reaction. No image credit.

    One type of severe reaction is ‘hypersensitivity,’ in which the immune system over-reacts to a substance that is foreign but not infectious, producing symptoms that can be mild (such as rashes) to severe (organ failure, even death). In this study, researchers studied an antiviral drug known to cause hypersensitivity in patients who carry a particular gene. Using x-rays at Brookhaven Lab’s National Synchrotron Light Source (NSLS), they were able to ‘see’ how at the molecular level, the drug binds to the protein created from the gene, triggering the immune response. Their work has produced new ways to predict whether a drug is likely to induce a gene-based allergic reaction.”

    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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