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World's Brightest Laser Could Pave Way for Lower-Radiation X-Rays

Live science: The world's brightest laser — which is so powerful that it can produce light pulses that are 1 billion times brighter than the surface of the sun — can "transform" visible light into X-rays, making the shape and color of objects appear different, new research shows.

These X-rays could be much less harmful than current computed tomography (CT) machines and provide much-higher-resolution images, the researchers said.

In the new study, published online June 26 in the journal Nature Photonics, a team from the University of Nebraska-Lincoln led by physicist Donald Umstadter described an experiment they had conducted using their superpowerful Diocles laser, named after an ancient Greek mathematician.

MORE: https://www.livescience.com/59795-brightest-laser-transforms-light-into-x-rays.html

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Synchrotron light used to show human domestication of seeds from 2000 BC

Bioengineer: Scientists from UCL have used the UK's synchrotron facility, Diamond Light Source, to document for the first time the rate of evolution of seed coat thinning, a major marker of crop domestication, from archaeological remains.

Writing in the journal Scientific Reports, the authors present evidence for seed coat thinning between 2,000 BC and 1,200 BC in the legume horsegram (Macrotyloma uniflorum), a bean commonly eaten in southern India.

By using the high-resolution X-ray computed tomography (HRXCT) technique on Diamond's I13-2 beamline, the researchers were able to measure for the first time the coat thickness throughout the entire seed.

MORE: https://bioengineer.org/synchrotron-light-used-to-show-human-domestication-of-seeds-from-2000-bc/

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Nature Chemistry issues its first retraction

Retraction Watch (BESSY II): For the first time in its eight-year history, Nature Chemistry has retracted a paper, citing “data integrity issues.” The 2010 paper, which explored how various iron-based molecules interact with water and ethanol, was withdrawn after the authors uncovered possible duplication in two images. According to the retraction notice, the authors could not provide the raw data to confirm their findings and could not reproduce the figures because the experimental set-up had been dismantled. The authors subsequently requested the paper be retracted because the issues undermined “our full confidence in the integrity of the study.” 

MORE: http://retractionwatch.com/2017/07/13/nature-chemistry-issues-first-retraction/

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Synthetic Ferrimagnet Nanowires Make More Efficient Memory Devices

ECN Magazine (Diamond): Racetrack memory is a potential next-generation solution for our digital storage devices. However, current experiments using single-layer ferromagnetic nanowires are less efficient than expected. New research published in Scientific Reports shows that replacing them with a double-layered synthetic ferrimagnet nanowire reduces electric current requirements by a factor of ten, and power requirements by a factor of one hundred. 

MORE: https://www.ecnmag.com/news/2017/07/synthetic-ferrimagnet-nanowires-make-more-efficient-memory-devices

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Scientists See Molecules 'Breathe' in Remarkable Detail

Newswise: In a milestone for studying a class of chemical reactions relevant to novel solar cells and memory storage devices, an international team of researchers working at the Department of Energy’s SLAC National Accelerator Laboratory used an X-ray laser to watch “molecular breathing” – waves of subtle in-and-out motions of atoms – in real time and unprecedented detail. These ripples of motion, seen with SLAC’s Linac Coherent Light Source (LCLS), allowed the team to study how energy is exchanged between light and electrons and leads to tension and eventually motion of atoms in an iron-based molecule that’s a model for transforming light to electric energy and switchable tiny molecular magnets. In a paper published in Nature Communications, the research team said these high fidelity, real-time measurements of ultrafast energy redistribution can provide key information to understand the function of many chemical, physical and biological light-induced phenomena.

MORE: http://www.newswise.com/doescience/?article_id=677721&returnurl=aHR0cHM6Ly93d3cubmV3c3dpc2UuY29tL2FydGljbGVzL2xpc3Q=

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Scientists set the record for creating the ‘squarest' ice cubes

The Irish News (LCLS): Scientists have set a new record for creating the most square-shaped ice cubes possible. International researchers say they have made “a near-perfect cubic arrangement of water molecules”, which is a form of ice that exists in the coldest areas of high-altitude clouds.The researchers say these frozen water droplets – which were nearly 80% cubic – are extremely hard to achieve on Earth.“While 80% might not sound ‘near perfect’, most researchers no longer believe that 100% pure cubic ice is attainable in the lab or in nature,” said Barbara Wyslouzil, project leader and professor at Ohio State University. 

MORE: http://www.irishnews.com/magazine/science/2017/07/11/news/scientists-set-the-record-for-creating-the-squarest-ice-cubes-1081602/

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Alien ice on Earth: Scientists discover how dense, extraterrestrial ice can form in just billionths of a second

Phys.org: Stanford researchers have for the first time captured the freezing of water, molecule-by-molecule, into a strange, dense form called ice VII ("ice seven"), found naturally in otherworldly environments, such as when icy planetary bodies collide. In addition to helping scientists better understand those remote worlds, the findings - published online July 11 in Physical Review Letters - could reveal how water and other substances undergo transitions from liquids to solids. Learning to manipulate those transitions might open the way someday to engineering materials with exotic new properties.

Read more at: https://phys.org/news/2017-07-alien-ice-earth-scientists-dense.html#jCp

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Scientists get first direct look at how electrons 'dance' with vibrating atoms

Phys.org: Scientists at the Department of Energy's SLAC National Accelerator Laboratory and Stanford University have made the first direct measurements, and by far the most precise ones, of how electrons move in sync with atomic vibrations rippling through an exotic material, as if they were dancing to the same beat. The vibrations are called phonons, and the electron-phonon coupling the researchers measured was 10 times stronger than theory had predicted—making it strong enough to potentially play a role in unconventional superconductivity, which allows materials to conduct electricity with no loss at unexpectedly high temperatures.

Read more at: https://phys.org/news/2017-07-scientists-electrons-vibrating-atoms.html#jCp

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European XFEL starts operation phase

Chemeurope.com: The world’s largest X-ray laser, the European XFEL, has now entered its operation phase. Over the past few weeks, engineers and scientists at European XFEL and DESY have been working to ensure that the experiment stations are equipped with instruments and that the X-ray beam meets the parameters needed to start doing experiments. On Friday, the European XFEL Council, the highest governing organ of European XFEL, agreed that the conditions for the start of operation have now been satisfied, and consequently released the funds designated for the operation phase. The X-ray laser produces extremely bright and short X-ray flashes that, with the help of specialised experiment stations, allow scientists to gain completely new insights into the atomic details and processes of the nanoworld. First experiments are now possible and have started for commissioning purposes; user operation with scientific research is scheduled to begin in September.

MORE: http://www.chemeurope.com/en/news/163998/european-xfel-starts-operation-phase.html

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Out of the blue: Medieval fragments yield surprises

Cornell Chronicle: Analyzing pigments in medieval illuminated manuscript pages at the Cornell High Energy Synchrotron Source (CHESS) is opening up some new areas of research bridging the arts and sciences.Louisa Smieska and Ruth Mullett studied manuscript pages from Cornell University Library’s Division of Rare and Manuscript Collections (RMC), dating from the 13th to the 16th centuries, using X-ray fluorescence (XRF) and spectral imaging analysis.“Our initial goal was to learn more about Cornell’s fragments and about trends in pigment use,” said Mullett, a medieval studies doctoral student. “An initial survey using a portable point XRF [p-XRF] instrument uncovered several things we weren’t expecting.”

MORE: http://news.cornell.edu/stories/2017/07/out-blue-medieval-fragments-yield-surprises

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Long duration experiments reach 1,000th day

Diamond: The first experiment placed on Diamond's Long Duration Experimental (LDE) facility, on beamline I11, has now been in place for 1,000 days. The experiment, led by Dr Claire Corkhill from the University of Sheffield, has used the world-leading capabilities of the beamline to investigate the hydration of cements used by the nuclear industry for the storage and disposal of waste. 

MORE: https://www.eurekalert.org/pub_releases/2017-07/dls-lde070317.php

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New Studies of Ancient Concrete Could Teach Us to Do as the Romans Did

LBL: A new look inside 2,000-year-old concrete – made from volcanic ash, lime (the product of baked limestone), and seawater – has provided new clues to the evolving chemistry and mineral cements that allow ancient harbor structures to withstand the test of time. The research has also inspired a hunt for the original recipe so that modern concrete manufacturers can do as the Romans did.A team of researchers working at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) used X-rays to study samples of Roman concrete – from an ancient pier and breakwater sites – at microscopic scales to learn more about the makeup of their mineral cements.

MORE: http://newscenter.lbl.gov/2017/07/03/ancient-concrete-could-teach-us-to-do-as-romans-did/

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Bringing bacteria’s defense into focus

ScienceBlog (CHESS): By taking a series of near-atomic resolution snapshots, Cornell University and Harvard Medical School scientists have observed step-by-step how bacteria defend against foreign invaders such as bacteriophage, a virus that infects bacteria.The process they observed uses CRISPR (clustered regularly interspaced short palindromic repeats) sites, where the cell’s DNA can be snipped to insert additional DNA.Biologists use CRISPR for genetic engineering experiments, but cells may have evolved the mechanism as part of a defense system. The cell uses these locations to store molecular memories of invaders so that they can be selectively eradicated at the next encounter.

MORE: https://scienceblog.com/495001/bringing-bacterias-defense-focus/

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New Mechanism for Keeping DNA Protein in Line Identified

Scicasts (SSRL & ALS): The actions of a protein used for DNA replication and repair are guided by electrostatic forces known as phosphate steering, a finding that not only reveals key details about a vital process in healthy cells, but provides new directions for cancer treatment research.The findings, published this week in the journal Nature Communications, focus on an enzyme called flap endonuclease 1, or FEN1. Using a combination of crystallographic, biochemical, and genetic analyses, researchers at the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) showed that phosphate steering kept FEN1 in line and working properly.

MORE: https://scicasts.com/channels/proteomics/2043-protein-functions/12694-new-mechanism-for-keeping-dna-protein-in-line-identified/

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Researchers develop pioneering X-ray technique to analyze ancient artifacts

Phys.org (Diamond): A pioneering X-ray technique that can analyse artefacts of any shape or texture in a non-destructive way has been developed by an international team of researchers led by the University of Leicester.                   The technique, which has been showcased in a paper published in the journal Acta Crystallographica A, uses X-ray diffraction (XRD) in order to determine crystallographic phase information in artefacts with very high accuracy and without causing damage to the object being scanned.Using the technique, researchers can identify pigments in paintings and on painted objects - which could potentially be applied in the future to help to clamp down on counterfeit artwork and artefacts and verify authenticity.

Read more at: https://phys.org/news/2017-06-x-ray-technique-ancient-artifacts.html#jCp

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Study on human skin microbiome finds archaea abundance associated with age

Phys.org (ALS): It turns out your skin is crawling with single-celled microorganisms—and they're not just bacteria. A study by the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) and the Medical University of Graz has found that the skin microbiome also contains archaea, a type of extreme-loving microbe, and that the amount of it varies with age.  The researchers conducted both genetic and chemical analyses of samples collected from human volunteers ranging in age from 1 to 75. They found that archaea (pronounced ar-KEY-uh) were most abundant in subjects younger than 12 and older than 60. Their study has been published in Scientific Reports in an article titled, "Human age and skin physiology shape diversity and abundance of Archaea on skin."

Read more at: https://phys.org/news/2017-06-human-skin-microbiome-archaea-abundance.html#jCp

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Vortex-Antivortex Pairs Found in Magnetic Trilayers

From newswise: A international team of researchers has discovered magnetic vortex-antivortex pairs arising from correlated electron spins in a newly engineered trilayer material. The discovery could advance memory cells and points to the potential development of 3-D magnetic logic circuits. The researchers from the Nanomaterials and Nanotechnology Research Center of the University of Oviedo in Spain, and the University of Porto in Portugal, reported their findings this week in Applied Physics Letters, from AIP Publishing. The collaboration also included a research group at Alba Synchrotron in Catalonia, Spain.

MORE: http://www.newswise.com/articles/vortex-antivortex-pairs-found-in-magnetic-trilayers